Organic solvents have universally been used to prevent gelation during the reaction of an aqueous phosphoric acid and an epoxy resin to form epoxy phosphate esters.

Examples of these methods include those described by U. S. Patent Nos. 4,164,487 and 4,289,812 issued to Martin. Martin describes the reaction of an epoxy resin with mixtures of phosphoric acid and water in inert solvents such as methyl ethyl ketone (MEK), dichloromethane or dioxane. According to Martin, such epoxy phosphate esters as described above can be neutralized and then stripped of all volatiles and then dispersed in water to form aqueous solvent-free dispersions.

Another example is German Patent No. DE 3009715, which describes the reaction of epoxy resins with aqueous solutions of phosphoric acid in the presence of a protic solvent such as ethylene glycol monoethyl ether or ethylene glycol monobutyl ether, for example, in a premix of polyphosphoric acid in DOWANOL EB instead of phosphoric acid to obtain epoxy phosphate ester resin solutions with lower viscosities. Similar technology is also described in U. S. Patent No. 4,397,970 issued to Campbell et al. It is also known that solvents are considered to be necessary in order to prevent gelation during the reaction of an aqueous phosphoric acid and an epoxy resin, that is, during the phosphorylation step, due to lowering the viscosity in the reaction mixture and concentration of the reactive components in the reaction mixture. Solvents such as alkoxyethanols have been described as preferred solvents, since they also act as solvent for water in the reaction mixture (for example, EP 174628). In this process, the alkoxyethanols react with epoxy groups and act as chain terminators at the same time during the phosphorylation step. The process requires high levels (for example greater than 20 percent) of the solvents such as DOWANOL EB glycol ether and n-butanol to form solutions and aqueous, solvent-containing dispersions of epoxy phosphate esters. Several epoxy phosphate ester solution products have been developed using solvent-borne technology such as described in EP 174628.

However, the route to solid epoxy phosphate esters has heretofore never been explore.

Epoxy phosphate ester solutions have been used in solvent-borne lacquers as well as in solvent-containing aqueous formulations after neutralization for heat cure applications. In more recent approaches, for example as disclosed in EP 0461567, dispersible epoxy phosphate ester resins have been developed by reaction of epoxy resins with a mixture of ethylenically unsaturated monomers in combination with polymerizable ethylenically unsaturated acidic phosphoric acid containing monomers and a radical initiator.

However, these reactions are performed in an organic solvent and therefore the dispersions still contain solvents.

Known water-borne epoxy resins for heat cure coating applications, notably epoxy-acrylate graft copolymers, generally employ a significant amount of organic solvent (400 to 720 grams solvent/kg solid) which is required in the manufacturing process of the water-borne lacquer and which is necessary to obtain stable, applicable aqueous resin dispersions.

As aforementioned, the synthesis of epoxy phosphate ester resins is known to be carried out in organic solution. It has not been known to prepare solid epoxy phosphate ester resins. It is therefore desired to provide a process for preparing solid epoxy phosphate ester resins, which can be used, for example, either as a solid in powder coating formulations, or which can be melted and subsequently dispersed in water without the aid of an organic solvent or any other volatile coalescing agent and which can be used in ultralow VOC heat-curable coating formulations.

One aspect of the present invention is a solid epoxy phosphate ester resin prepared by reacting: (a) an epoxy resin; (b) a phosphoric acid source material; (c) a non-volatile hydroxy-functional controlled propagation reaction reagent; and (d) water.

The solid epoxy phosphate ester resin is prepared from an epoxy resin, preferably having an average of greater than one vicinal epoxy group, and a phosphoric acid source in presence of water by utilizing a non-volatile hydroxy-functional controlled propagation reaction reagent and without any organic solvents present. The controlled propagation reaction reagent (CPRR) contains at least two or more hydroxyl groups in the

molecule such as polyol compounds. Examples of polyols include diol compounds such as diethylene glycol and triethylene glycol.

A non-volatile hydroxy-functional controlled propagation reaction reagent is a compound, which reacts with the epoxy resin, phosphoric acid source and water to become a part of the chemical structure the reaction product. In so doing, the CPRR causes a build- up in molecular weight, and at the same time, preventing gelation of the reaction mixture during the process of making the resulting reaction product at the stage of the reaction of the epoxy groups with the phosphoric acid source and water. The above-mentioned build-up of molecular weight through the reaction of two epoxy groups with one molecule of the controlled propagation reaction reagent is called"propagation"herein.

The term"solid'is used herein to describe the physical state of the epoxy phosphate ester resin as solid at technically manageable temperatures, at which the material will maintain its solid form, such as flakes, granules or powder."Technically manageable temperatures"generally mean temperatures below about 40°C. However it could also include storage under cooling conditions, that is, below room temperature.

"Room temperature"refers to a temperature of about 20°C.

The term"non-volatile"is used herein in the sense that the substance referred to has a boiling point above 190°C at normal atmospheric pressure.

Another aspect of the present invention is a process for manufacturing a solid epoxy phosphate ester resin composition by reacting: (a) an epoxy resin; (b) a phosphoric acid source material; (c) a non-volatile hydroxy-functional controlled propagation reaction reagent; and (d) water.

Yet another aspect of the present invention is directed to an aqueous dispersion preferably excluding a solvent comprising: (1) the solid epoxy phosphate ester resin composition described above; (2) a neutralizing agent; and (3) water.

Yet another aspect of the present invention is directed to a water-borne heat- curable formulation preferably excluding a solvent comprising: (1) the solid epoxy phosphate ester resin composition described above; (2) a neutralization agent; (3) a curing agent; and (4) water.

Still another aspect of the present invention is a heat-curable powder coating formulation comprising: (1) the solid epoxy phosphate ester resin composition described above; (2) a solid epoxy resin; and (3) optionally fillers and additives as generally used by those known in the art of powder coatings such as pigments, additional catalysts and flow additives.

It has been demonstrated that solid epoxy phosphate ester resins modified with the hydroxyl-functional controlled propagation reaction reagents render stable aqueous resin dispersions after neutralization and can successfully be formulated in ultralow VOC heat-curable coating systems without the use of an organic solvent or any other volatile coalescing agent. The solid epoxy phosphate ester resins of the present invention can also be used as components in curable powder coating systems as well.

In accordance with the present invention a solid epoxy phosphate ester resin is prepared by reacting an epoxy resin, a phosphoric acid source material, a non-volatile hydroxy-functional controlled propagation reaction reagent (CPRR) and water.

The resulting solid epoxy phosphate ester resin is generally comprised of a mixture of several resulting reaction product components. The solid reaction product generally includes, for example, the following components identified by Formulas (I)- (VIII): Formula (I) phosphate monoester:

Formula (II) phosphate diester: Formula (III) phosphate triester: Formula (IV) free phosphoric acid Formula (V) a component capped by the hydroxy-functional controlled propagation reaction reagent: Formula (VI) a component made by propagation through the hydroxy-functional controlled propagation reaction reagent: Formula (VII) hydrolyzed species: and unreacted controlled propagation reaction reagent wherein A is representing the backbone structure of the epoxy resin, and E is derived from a glycidyl group attached to the backbone structure, resulting in a structural unit of the type HO-CH2-CH (OH)-CH2-O-as derived from the epoxy group by adding water; R is

representing the backbone structure of a hydroxy-functional controlled propagation reaction reagent.

The above structural units in Formulas (I)- (VIII) are part of a distribution, which may vary depending on the amounts and types of reactants. Generally, the amount of Formula (I) is from 1 mole percent to 50 mole percent, the amount of Formula (V) is from 5 mole percent to 60 mole percent, the amount of Formula (VI) is from 2 mole percent to 30 mole percent and all other components are from 20 mole percent to 80 mole percent, based on the molar sum of Formulas (I) to (III) and Formulas (V) to (VII).

The epoxy phosphate ester resin product has a weight average molecular weight (Mw) greater than that of the initial epoxy resin, indicating that chain extension has taken place. Preferably, the Mw increase of the epoxy phosphate ester resin product from the initial epoxy resin should be greater than about 1 percent, more preferably greater than about 20 percent and most preferably greater than about 50 percent. The solid epoxy phosphate ester resin product has a Mettler Softening Point (MSP) of from 0°C to 200°C and preferably from 60°C to 150°C.

As aforementioned, in general, the solid epoxy phosphate ester resin of the present invention is prepared by reacting (a) an epoxy resin with (b) a phosphoric acid source material such as phosphoric acid or a derivative of phosphoric acid, (c) a non-volatile hydroxy-functional controlled propagation reaction reagent; and (d) water.

The epoxy resin used as reactant material (a) in the composition of the present invention may be any suitable epoxy resin such as those known to those skilled in the art. Any epoxy resin can be used in the present invention so long as the molecule has an epoxy function (oxirane ring) attached to the molecule prior to any modification of the epoxy resin according to the reaction process of the present invention. Suitable epoxides for the practice of the present invention include for example polyol polyether epoxides which can be represented by either the following Formulas (X) and (XI): Formula (X): Formula (XI):

wherein Q, independently in each occurrence, is either Q1, Q2, or Q3 as follows: Q, : In Q3 k may be 1 or 2, that is, indicating Qk being either Q, or Q2; S is a C2 to Cg alkylene group or a-group in which R6 is best described as (R'-O) m-R' in which R7 is a C2-C8 alkylene or alkenylene group and m is 1 to 8. n is an integer of from 0 to 40, r is zero, 1 or 2 and, independently of each occurrence; R'is H, methyl or ethyl; R2 is-Br,-Cl or a C, to C4 alkyl or alkenyl group; R3 is a C1-C4 alkylene or alkenylene group, a-0-R6-O-group in which R6 is a C2-C8 alkylene or alkenylene group, -C (CF3) 2-,-CO-,-SO2-,-S-,-O-or a valence bond; R4 is -Br, -Cl, or a C, to C4 alkyl or alkenyl group; and

Rs is H or alkyl of 1 to 12 carbons.

The most preferred epoxides are those of Formula X wherein n is from 2 to 40, Q is a bisphenol residue and R'is H.

Typical epoxy resins useful in the present invention are resins such as bisphenol A based epoxy resins. However, the epoxy resins could also contain other structures such as bisphenol-F, and bisphenol-S, phenolphthaleine. Exemplary bisphenols and phenols having two hydroxy groups attached to one phenol ring can be found in The Chemistry of Phenolic Resins; R. W. Martin; pp. 64-80; Wiley & Sons N. Y.; N. Y. (1956).

Other possible structures of bisphenols and diglycidylethers of bisphenols may be found in Handbook of Epoxy Resins; Lee H. & Neville K.; pp. 2-10 to 2-25; McGraw-Hill; N. Y.; N. Y.

(1967, reissue 1982). Also structures originating from the use of aliphatic glycol epoxies, such as D. E. R. Tm 732 (Trademark of The Dow Chemical Company), in the manufacture of an advanced resin in combination with bisphenols and epoxy resins containing bisphenol groups are possible and can be manufactured according to processes known to those skilled in the art. Other possible structures of diepoxides can be found in Epoxy Resins; C. May; Marcel Dekker; N. Y.; N. Y. (1988) and Handbook of Epoxy Resins; Lee H. & Neville K.; pp. 2- 10 to 2-25; McGraw-Hill; N. Y.; N. Y. (1967, reissue 1982).

In the present invention, any epoxy resins having an average of greater than or equal to one epoxy group per molecule, can be used. Suitable epoxy resins include, for example, those having an epoxy equivalent weight of from 151 to 3,500, more suitably from 158 to 1,000, even more preferred from 400 to 800. Preferred epoxy resins which can be used herein, are those having two vicinal epoxy groups such as diglycidyl ethers of bisphenol A, bisphenol K, bisphenol F, bisphenol S, bisphenol AD, aliphatic phenols and mixtures thereof. The most preferred epoxy resins are diglycidyl ethers of bisphenol A and bisphenol F and diglycidyl ethers of aliphatic polyether polyols.

The epoxy resin starting material used in the present invention may be a solid epoxy resin, preferably having a Mettler softening point below about 180°C, more preferably below about 120°C, even more preferably below about 100°C. There is no limit to a lower Mettler softening point of the epoxy resin, however the use of epoxy resins, having a Mettler softening point greater than about 40°C, is preferred.

The epoxy resin used prior to making the epoxy phosphate ester may be for example (1) a known or commercially available epoxy resin which is either in a liquid state already or which can be melted prior to use, (2) an advanced epoxy resin which can be

prepared for example (i) by advancing a phenolic-terminated compound having an average of greater than or equal to one hydroxyl group per molecule such as bisphenol-A with a known or commercially available liquid epoxy resin or (ii) by advancing a phenolic compound such as bisphenol A with an epihalohydrin such as epichlorohydrin in a process called a taffy process as described in the art, for example, in Handbook of Epoxy Resins; Lee H. & Neville K.; pp. 2-6 to 2-9; McGraw-Hill; N. Y.; N. Y.; (1967, reissue 1982), such that an epoxy resin results having an average of greater than or equal to one epoxy group per molecule or (3) a combination of any of the above epoxy resins. The resulting molten epoxy resin can then be modified with a phosphoric acid source material, a hydroxy-functional controlled propagation reaction reagent and water as described in the present invention.

When the epoxy resin used in the present invention is prepared by the reaction of an epoxy resin and a phenolic compound having an average of more than one hydroxyl group, the epoxy resin and the phenolic compound may be used in an amount to provide an epoxy: phenolic component ratio by weight which could vary such that an epoxy resin results containing 0.1 to 28.1 weight percent of epoxy groups; for example, the reaction components of diglycidyl ether of bisphenol-A and bisphenol-A could vary from 60: 40 to 99: 1; more preferably from 65: 35 to 99: 1 by weight.

In another embodiment, it is possible to have the hydroxy-functional controlled propagation reaction reagent, or some parts of the hydroxy-functional controlled propagation reaction reagent, already present in the reaction mix during the advancement reaction to form the advanced epoxy resin which is used as Component (a) in the present invention.

Another advanced epoxy resin useful as the epoxy starting material (a) in the present invention can also be prepared from other starting compounds such as different types of phenols (such as bisphenol F) and/or different types of epoxy resins (such as aliphatic glycol or polyether polyol liquid epoxy resins).

Also, if desired, some of the epoxy functionality of the epoxy resin can be reduced prior to the reaction of the epoxy resin with the phosphoric acid source, the hydroxy-functional controlled propagation reaction reagent and water by reacting the epoxy resin with other compounds, in particular acids, such as aliphatic acids or aromatic acids, such as stearic acid or benzoic acid. Alternately, mono-functional phenols, such as p-tert butyl phenol, can be reacted with the epoxy resin; or the epoxy resin can be advanced in the presence of glycols or other aliphatic hydroxy-functional compounds.

Several commercially available epoxy resins useful in the present invention include for example, D. E. R. Tm 671, D. E. R. Tm 691, D. E. R. T" 662E, D. E. R. TU 663UE and D. E. R. Tm 664UE (Trademarks of The Dow Chemical Company), which are commercially available from The Dow Chemical Company. Other commercially available epoxy resins include for example, D. E. R. Tt 331 L; D. E. R. TM 383J; D. E. R. 661; D. E. R. Tm 664; D. E. R. TM 732; and D. E. N. Tm 438 (Trademarks of The Dow Chemical Company) resins, also available from The Dow Chemical Company.

The epoxy resin used in the present invention is used in an amount of generally from 60 percent to 97 percent by weight and preferably from 80 percent to 92 percent by weight.

In the present invention, the epoxy resins are not limited to the above- mentioned epoxy resins, but include any of the various known epoxy resins which are well described in, for example, U. S. Patent Nos. 4,164,487,4,289,812,4,397,970,4,868,059 and 5,070,174, and"The Handbook of Epoxy Resins"by H. Lee and K. Neville, published in 1967 by McGraw-Hill, New York, as well as in"Epoxy Resins"by C. May, published in 1988 by Marcel Dekker; N. Y.

In the present invention, the above-mentioned epoxy resin (a) is modified by reacting the epoxy resin with a phosphoric acid source material reactant (b), a non-volatile hydroxy-functional controlled propagation reaction reagent reactant (c) and water (d).

The phosphoric acid source material useful as the reactant (b) in the composition of the present invention includes for example, phosphoric acid, super phosphoric acid, phosphoric acid derivatives and combinations thereof. Phosphoric acid derivatives include, for example, those derivatives which comprise of free or blocked PO (OH), moieties with x being one to three, such as water-free or diluted phosphoric acid or polyphosphoric acid, more precisely 100 percent orthophosphoric acid, the semi-hydrate (2H3PO4. H20) and aqueous solutions containing at least about 18 weight percent H3PO4 (about 1 mole H3P04 per 25 moles of water). The various condensed forms (polymeric, partial anhydrides) of phosphoric acid, pyrophosphoric acid, orthophosphoric acid, triphosphoric acid and partially hydrolyzed phosphorous pentoxide may also be used.

It is not to be inferred that the phosphoric acid source material must actually be derived from the reaction of phosphorous pentoxide with water. It is only necessary that the phosphoric acid source material be at least theoretically preparable from phosphorous pentoxide. For example, the phosphoric acid source material may be reaction mixtures of

polyphosphoric acid or phosphorous pentoxide with hydroxy-functional compounds other than water such as alcohols, diols, or phenols. These substances may actually still contain acidic P-OH groups. If such acidic P-OH groups are not present in a substance, but could be generated again through hydrolysis, these substances may also be used. Examples include phosphate esters such as trialkyl, dialkyl and monoalkyl phosphate and mixtures thereof, with alkyl being a C, to Cg alkylene group, and phosphate esters such as triaryl, diaryl and monoaryl phosphate and mixtures thereof, with aryl being phenol; an alkyl- substituted phenol with one, two or three C, to C4 alkylene group (s); a halogen substituted phenol with one, two or three halogen substituents may be used in the present invention.

The process of making such compounds mentioned above could be initiated from other phosphoric acid derivatives, such as phosphoric acid halogenides, for example, POC13 or through transesterifications from phosphate esters with suitable methods such as those known to someone skilled in the art.

Ordinarily aqueous phosphoric acid solutions will be the preferred source of phosphoric acid used in the present invention. Preferred are phosphoric acids having an H3PO4 concentration of from 20 to 100 percent by weight in water.

The amount of phosphoric acid source material used in the present invention is generally from 0.1 equivalents to 2.8 equivalents of phosphoric acid, and preferably from 0.2 equivalents to 1.0 equivalents of phosphoric acid to one equivalent of epoxy groups.

The non-volatile hydroxy-functional controlled propagation reaction reagent (CPRR) useful as the reactant (c) in the composition of the present invention are substances which contain hydroxyl groups which will at least partially react with the epoxy groups of the epoxy resin (a) thus advancing the resin to a higher molecular weight while preventing a possible polymer network formation, also known as gelation, during the modification reaction of phosphoric acid contributing substances (b) and water (d) with the epoxy groups of the epoxy resin (a).

The hydroxy-functional controlled propagation reaction reagent (c) useful in the present invention include polyhydroxy-functional substances including aromatic and aliphatic substances containing hydroxyl groups. The aromatic substances containing hydroxyl groups useful in the present invention may be, for example, those phenolic compounds described in The Chemistry of Phenolic Resins, R. W. Martin, pp. 64-80, Wiley & Sons, N. Y., N. Y. (1956).

Preferably, the controlled propagation reaction reagent include substances containing aliphatic hydroxyl groups; these could be non-volatile-polyhydroxy-functional substances such as trihydroxy-functional, more precisely glycerin, trimethylol propane or more preferred dihydroxy-functional substances such as hydroxyl-terminated polyether more precisely such as glycols, polyglycols, 1,3-dihydroxy propane, 1,4-dihydroxy butane, poly- THF (poly-tetrahydrofurane) and any other dihydroxy alkane with having between 5 to 10 carbon atoms between the glycol groups. Non-volatile in this invention is used to describe a substance having a boiling point greater than 190°C at normal conditions. More preferred are diols such as ethylene glycol, or polyethylene glycols having a number average molecular weight of from 62 to 3000; even more preferred are polyethylene glycols having a number average molecular weight of from 62 to 1000; most preferred are polyethylene glycols having a number average molecular weight of from 62 to 300. The hydroxyl- functional controlled propagation reaction reagents mentioned above may also be used as mixtures in this invention.

The epoxy phosphate ester resin product of the present invention generally contains at least about 20 percent preferably at least about 30 percent and more preferably at least about 35 percent of the hydroxyl-functional controlled propagation reaction reagent chemically bonded into the epoxy phosphate ester resin.

Optionally, the hydroxy-functional controlled propagation reaction reagent (c) useful in the present invention could also be used in combination with a capping agent such as for example mono-functional phenols such as phenol and substituted phenols, with one, two or three substituents, more precisely alkyl and hydroxy alkyl and halogen and aryl substituents, with alkyl being a C, to Cg alkenyl group; hydroxy alkyl being a C, to Cg alkenyl group having one or more hydroxyl functional groups attached; and aryl being another phenyl based group which could also be substituted by one, two or three alkyl and hydroxy alkyl and halogen substituents.

Alternatively and optionally, the hydroxy-functional controlled propagation reaction reagent (c) useful in the present invention could also be used in combination with a capping agent such as for example mono-functional carboxylic acids, either in which the carboxylic acid group is attached to an aliphatic or to an aromatic carbon atom. The acids may be unsubstituted or substituted acids. Examples include caprylic acid, laevulinic acid, stearic acid, palmitinic acid, chlorobutyric acid, phenylacetic acid and aromatic acids such as benzoic acid or alkyl and aryl and halogen substituted benzoic acids and with alkyl being a C, to Cg alkenyl group, aryl being another phenyl group.

The amount of hydroxy-functional controlled propagation reaction reagent compound (c) used in the present invention is generally from 0.1 equivalents to 3.9 equivalents to one equivalent of epoxy groups, more preferably from 0.2 equivalents to 2.0 equivalents to one equivalent of epoxy groups. In the embodiment where hydroxy- functional controlled propagation reaction reagents compounds are used in combination with the mono-functional capping agents mentioned above, then the total amount of all these components should not exceed a total of 3.9 equivalents to one equivalent of epoxy groups.

The other component (d) of the composition of the present invention is water.

Water, as part of the reaction mixture, is a vital component which allows hydrolysis of the initially formed epoxy phosphate triesters to lower esters such as the monoester (that is, free water is present in the reaction mixture). The amount of water used in the present invention is generally from 1 percent to 7 percent by weight, preferably from 2 percent to 6 percent by weight and more preferably from 2.3 percent to 5.0 percent by weight of the total reaction mixture.

The phosphoric acid group is distributed in the resin in the form of free phosphoric acid, phosphate monoester, diphosphate ester and triphosphate ester. The phosphate monoester is preferred. Hydrolysis of triesters will lead to diesters and then subsequently to monoesters and free phosphoric acid, because of the water component present during the reaction of components (a)- (d). Though phosphate monoester is the preferred form of phosphoric acid containing species, the modified epoxy phosphate ester resin of the present invention may still contain a small quantity of diesters, triesters and free phosphoric acid in addition to monoesters, but should contain at most about a trace amount of epoxy groups.

Further, the phosphate groups existing at the end of molecules can provide good corrosion resistance inherently possessed by the phosphoric acid. Further, the phosphoric acid residues may catalyze curing of the resultant coated film.

In carrying out the process of the present invention, it is not critical in what order the starting materials are mixed, with the exception that it is preferable to mix component (a) and component (c) prior to component (b) and component (d). In this reaction, the process will control whether a gel is formed or not. To prevent obtaining a gel, the preferred alternative methods include for example: (1) a mixture of the three components (b)- (d) can be added to the epoxy resin component (a) all at once, (2) the water component (d) can be added last to the other components, (3) the water component (d) can be added in

combination with phosphoric acid source material (b) to the other components, (4) the water component (d) can be added to a mix of component (a) and (c) prior to the addition of the phosphoric acid source material (b), (5) the phosphoric acid source material (b) can be added in combination with the hydroxy-functional controlled propagation reaction reagent compound (c) to the other components, or (6) the phosphoric acid source material (b) can be added last to a combination of all other components.

Another embodiment of the process of the present invention is to advance a liquid epoxy resin with a phenolic material such as bisphenol A in the presence of the hydroxy-functional controlled propagation reaction reagent or a mixture of hydroxy-functional controlled propagation reaction reagents and then to proceed further as described above.

In still another embodiment of the process of the present invention, a mixture of the three components (b)- (d) is first charged into a reaction vessel and then the epoxy resin component (a), in molten form or in solid form, is added to the mixture of three components (b)- (d); and then the process is carried out further as described above.

The reaction between the components (a)- (d) to make the solid epoxy phosphate ester resin is carried out at a reaction temperature which is at least above the melting point of the epoxy resin component (a) in order to allow proper mixing of the components (a)- (d). The reaction temperature of the process is generally from 60°C to 200°C and preferably from 100°C to 160°C. The pressure of the process is generally from atmospheric pressure (96 kPa) to 1555 kPa, and preferably from atmospheric pressure to 626 kPa. The reaction mixture is normally vigorously stirred and is heated for a time sufficient to complete the reaction. The reaction time is generally from 5 minutes to 6 hours.

The preferred reaction time is between 15 minutes and 4 hours, the most preferred reaction time is between 30 minutes and 2 hours. The reaction is carried out in the absence of additional solvent. The result of the above reaction is a molten polyhydroxy polyether phosphate ester resin product. The molten product can then be cooled to a solid form and thereafter the solid product can be comminuted to particles by any mechanical means known in the art such as milling, flaking and grinding, for example, to a particle size of less than 40 um in size.

The solid epoxy phosphate ester resin prepared in accordance with the present invention is advantageously used, for example, for making an aqueous dispersion.

An aqueous dispersion of the present invention is made by reacting the solid epoxy phosphate ester resin with a neutralizing agent and water. The neutralizing agent useful in

the present invention may be, for example, a hydroxide anion-containing base, such as an inorganic base, such as sodium hydroxide or potassium hydroxide, also a tetra-substituted organic ammonium hydroxide such as tetraalkyl-or monoaryl trialkyl-or diaryl dialkyl-or triaryl alkyl ammonium hydroxide, with alkyl being an alkyl group consisting of one to twenty carbon atoms and aryl being phenol or alkyl substituted phenols having one, two or three substituents which could be alkyl groups consisting of 1 to 20 carbon atoms.

Other suitable neutralizing agents include ammonia and organic amines such as mono-, di-and tri-substituted amines in which either alkyl or aryl groups are compounding the substituents, alkyl groups consisting in this case of one to twenty carbon atoms, which could also have additional substituents attached such as hydroxyl-functional groups or amine groups or aminoalkyl amine groups or alkoxyalkyl amine groups; and aryl being phenol or alkyl or amino substituted phenols having one, two or three substituents which could be alkyl groups consisting of 1 to 20 carbon atoms, which could also have additional substitutes attached such as hydroxyl functional groups or amine groups. Typical examples of the neutralizing agent are mono-, di-, tri- (methyl-, ethyl-, propyl-, 2-hydroxy ethyl-, phenyl- ) amines, and isophorone diamine. Also possible neutralizing agents useful in the present invention are derived from combinations of amines such as N, N,-dimethyl ethanol amine, ethylene diamine, aniline, and diamino benzene. Alternatively, also possible useful neutralizing agents are polymeric amines such as mono-, diamino-, polyethylene glycols.

Suitable amine compounds which can also be used in the present invention as the neutralizing agent include for example those described in U. S. Patent Nos. 4,289,812 and 4,397,970; for example, alkanol amines such as N, N-dimethyl ethanol amine.

In carrying out the process of the present invention for making the aqueous dispersions, a melt of the solid epoxy phosphate ester resin is first neutralized with the neutralizing agent. Preferred temperatures are as low as possible, but as high as necessary to keep the epoxy phosphate ester resin in a melt which can be stirred. If the temperature of the resin melt is higher than the boiling point of the amine used, then the amine is preferably added under pressure which should be at least as high as the vapor pressure of the amine used at the temperature of addition.

After addition of the neutralizing agent, the neutralized resin melt is slowly dispersed in water. This could either be done by slowly adding the resin melt into the water or by slowly adding the water into the resin melt. If water is to be added at temperatures higher than the boiling point of water, then water is preferably added under pressure, which

needs to be at least as high as the vapor pressure of water used at the temperature of addition. The temperature of addition again is controlled by the temperature necessary to keep the resin melt stirrable.

In the process of the present invention, the epoxy phosphate ester resins can be made water-soluble by adding at least one amine compound to the resin to adjust its pH to preferably between 6 and 11, more preferably between 7 and 10. If the pH of the adjusted epoxy phosphate ester resin is outside the pH range of 6 to 11, the resultant solution may have poor stability.

In the present invention, neutralization is done without any solvent present, with the solid epoxy phosphate ester resin being in a liquid state. If the resin is in a liquid state below the boiling point of water then water could already be present during the neutralization. However the preferred approach is to add the amine to the resin melt first and then mix with water thereafter.

The aqueous dispersions or slurries of the present invention prepared as described above are advantageously used to prepare water-based formulations for heat- cure coating applications such as for can and coil or general appliance.

In the present invention, a water-borne coating composition can be prepared by mixing (1) the epoxy phosphate ester resin prepared as described above, (2) the neutralizing agent, (3) a curing agent (also referred to herein interchangeably as a hardener or cross-linking agent) and (4) water. For water-borne coatings, any known water-soluble or water dispersible curing agent can be used. The curing agent used may be a resole type hardener, also known as phenol formaldehyde hardener; a melamine-formaldehyde cross- linker; a benzoguanamine-formaldehyde cross-linker or a urea-formaldehyde cross-linker or an isocyanate curing agent such as, for example, Desmodur N3400 commercially available from Bayer AG, Germany.

In preparing a water-based formulation any hardener can be used, which can be molten with the epoxy phosphate ester resin at a temperature sufficient to obtain a melt of the epoxy phosphate ester resin or which is already liquid at this temperature or which can be dispersed into the epoxy phosphate ester melt by any other means. Alternatively, both the epoxy phosphate ester resin and the hardener could be dispersed by extrusion.

In one embodiment of the present invention, the solid epoxy phosphate ester resin may be used in combination with a cross-linking agent for example, a resole type cross-linker to form a stable, heat-curable formulation."Stable"is used in the sense that the

dispersion does not settle more than 20 percent within 4 weeks of storage time at room temperature or cures during storage at room temperature within 4 weeks.

In yet another embodiment of the present invention the solid epoxy phosphate ester may be used in combination with a melamine-formaldehyde type cross-linker to form a stable heat-curable formulation.

A nonionic surfactant having a melting point sufficiently low to melt at the mixing temperature may optionally be added to the formulation to stabilize the formulation and to improve the film appearance after curing to obtain defect-free films. Nonionic surfactants, such as, for example, polymeric alkoxylates, having a HLB value of from 5 to 25, preferably from 10 to 20, can be used. Numerous surfactants useful in the present invention include, for example, those polymeric surfactants which are commercially available from Uniqema under the trademark of Atsurf.

In one embodiment, up to, for example 10 percent of a nonionic surfactant, for example, Atsurf* polymeric surfactant may be added to the formulation of the present invention which keeps a hardener, which is non-miscible with water, in the dispersion and which upon curing of the formulation gives a defect-free cured film.

In case of the hardener being water-soluble or being already in a dispersed state, it can also be mixed with the aqueous epoxy resin dispersion and thus form a heat- curable or thermosettable coating formulation.

Water-borne formulations can also be prepared by mixing first a water dispersible hardener with a surfactant and then mixing with an aqueous dispersion of the epoxy phosphate ester resin; or by mixing an aqueous dispersion of water-dispersible hardeners, with or without containing a surfactant, with an aqueous dispersion of the epoxy phosphate ester resin.

The coating composition may also include an appropriate amount of other optional additives known in the art such as pigments, plasticizers, coloring agents, flow modifiers and/or curing accelerators.

In carrying out the process of the present invention for making the aqueous heat-curable formulations, a melt of the epoxy phosphate ester resin (1) is neutralized with the neutralizing agent (2). Preferred temperatures are as low as possible, but as high as necessary to keep the epoxy phosphate ester resin in a melt which can be stirred. If the temperature of the resin melt is higher than the boiling point of the amine used, then the amine is preferably added under pressure, which needs to be at least as high as the vapor

pressure of the amine used at the temperature of addition. To the neutralized resin melt, the cross-linker (3) is added and mixed. Optionally, a nonionic surfactant (5) may be added as well. The mixing temperature has to be high enough to ensure proper mixing. Alternatively, the surfactant (5) can be added before or in combination with the cross-linker (3). It is also possible to add components (2), (3) and (5) altogether to the resin melt (1). Alternately, components (2), (3) and (5) could be premixed and (1) could be added to this premix. After addition of all components, the melt is slowly dispersed in water. This could either be done by slowly adding the resin melt into the water (4) or by slowly adding the water into the resin melt. If water is to be added at temperatures higher than the boiling point of water, then water is preferably added under pressure, which needs to be at least as high as the vapor pressure of water at the temperature of addition. The temperature of addition again is controlled by the temperature necessary to keep the resin melt stirrable.

The pH of the resulting heat-curable formulation should be between 6 and 11, preferably between 7 and 10. If the pH of the adjusted epoxy phosphate ester resin is outside the pH range of 6 to 11, the resultant solution may have poor stability.

If the hardener itself is water soluble or is already dispersed in water or in any other liquid form, such as solvent-borne, then it may alternately be mixed with an aqueous dispersion of the epoxy phosphate ester resin at temperatures between 5°C and 100°C, preferably between 20°C and 80°C. Both dispersions need to be in such a state which allows proper mixing.

Curing of the formulation is between 30°C to 300°C, most preferably between 130°C to 220°C.

In yet another embodiment of the present invention the solid epoxy phosphate ester may be used in combination with solid epoxy resins, fillers and additives as generally used by those known in the art of powder coatings such as pigments and flow additives to form a heat-curable powder coating composition. Curing of the powder is done preferably at temperatures between 130°C and 250°C. While the epoxy phosphate ester of the present invention can be used with water and water-soluble curing agents to prepare water-borne coating compositions, it is also possible to use the resin in solvent-based coating compositions as well. The water-borne coating compositions are preferred from an environmental view point.

Thus, the epoxy phosphate ester resins of the present invention can also be used to prepare a solvent-borne coating compositions. Suitable organic solvents which can

be used as a diluent to adjust viscosity include, for example, the glycol-type solvents such as glycol monoether-type solvents, alcohol-type solvents, aromatic-type solvents and ketone- type solvents (such as methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone).

These solvents can be used alone or in combination.

The coating compositions of the present invention are useful in applications including, for example, can coating and general metal coating.

The following examples are for purposes of illustration and are not to be construed as limiting the scope of the present invention, which is to be determined only by the claims appended with this specification. All parts are by weight unless otherwise specified.

In the following Example the Tg of the epoxy phosphate ester resin product was measured by DSC, its melt viscosity was measured by an ICI cone and plate viscosimeter, and its Mw was measured by GPC.

Example 1: A. Epoxv Phosphate Ester Resin Synthesis 80.90 g of diethylene glycol, 11.73 g of o-phosphoric acid (85 percent) and 21.0 g of deionized water were charged into a 1 L 5-neck round-bottom glass reactor, equipped with a nitrogen inlet, water cooled condenser, an agitator and an electrical heating mantle which was connected to a temperature control unit, and mixed under a nitrogen blanket. Then 700 g of D. E. R. 662E solid epoxy resin flakes, having an EEW (epoxide equivalent weight) of 601 and an Mw of 3545, were added into the reactor. The mixture of solid resin flakes and liquid was gradually heated to about 100°C within about 30 minutes with no agitation. As soon as enough epoxy resin was molten to allow stirring, the agitator was started at slow speed. While stirring the temperature controller was set to 138°C. An exothermic reaction was observed, starting at about 127°C and ceiling at about 160°C.

Foaming was observed during this stage and the foam filled about 90 percent of the reactor volume. After the peak exotherm had been reached the temperature controller was set to 145°C and the reaction mixture was kept at 145°C for about four hours. The reaction itself was completed when all epoxy groups had been consumed (EEW greater than 43000; this number indicates that there are less than 0.1 weight percent of epoxy groups present, which is the lowest reliable analytical significance level for the presence of epoxy in the resin in the laboratory at the time of the experiments) which occurred within about two hours. The

reaction mixture was poured onto aluminum foil and was allowed to cool to room temperature resulting in a solid resin product.

The product had a glass transition temperature (Tg) of about 41 °C as measured by DSC, a melt viscosity of about 4700 mua-s at 150°C as measured by an ICI cone and plate viscosimeter, and an Mw of 6631 as measured by GPC.

The following distribution of phosphoric acid groups was determined: by 3'P NMR: free H3PO4 10 mole-% phosphate monoester 55 mole-% phosphate diester 27 mole-% phosphate triester 8 mole-% The amount of unreacted diethylene glycol present in the resin was determined using GC to be approximately 6.3 weight percent, which corresponds to a consumption of about 36 percent of the total amount of glycol.

The product was analyzed in detail by'3C and 3'P NMR using one and two- dimensional techniques. The following composition was determined: Of all structural groups present in the final product, as derived from the former epoxy groups, and related to the Formulas (I) to (III) and (V) to (Vil), approximately 40 mole- percent have been formed from epoxy groups by mono capping with diethylene glycol, 5 to 10 mole-percent have been derived from two epoxy groups having reacted with one molecule of diethylene glycol on both sides of the glycol, leading to propagation, less than 0.3 mole-percent are the reaction product of three epoxy groups with one molecule of phosphoric acid to form a phosphate triester, about 2 mole-percent are the result of the reaction of two epoxy groups with one molecule of phosphoric acid to form a phosphate diester and about 5 mole-percent of a phosphate monoester as derived from the reaction of one epoxy group with one molecule of phosphoric acid are present. The balance to 100 mole percent is made up with hydrolyzed species.

B. Dispersion Formulation Preparation 150 g of the solid epoxy phosphate ester resin, prepared in step A, 10 g of deionized water and 2.00 g of dimethylethanolamine were charged to a 500 mL, 5-neck round-bottom glass reactor, equipped with a nitrogen inlet, water cooled condenser, 250 mL dropping funnel, an agitator and an electrical heating mantle which was connected to a

temperature control unit, and heated slowly to 90°C under a nitrogen blanket. No agitation was applied. When the reaction mix had softened enough to allow stirring, slow stirring was started. The pulpy mixture was stirred at 95°C for about 30 minutes. Then 215.0 g of deionized water were added into the reaction mix at a temperature between 85°C to 95°C within about 30 minutes. Then the dispersion was stirred for another one hour at 95°C, then cooled and bottled. The dispersion had a non-volatile content of about 37.5 weight percent, a pH of about 7.2 and a Brookfield viscosity of about 1000 mua-s at 23°C.

The particle size of the dispersion was determined to be between 1500 and 2800 A (Angstrom). The dispersion showed excellent storage stability (more than 2 months at 40°C).

C. Heat-curable Coatina Dispersion Formulation Preparation 150 g of the solid epoxy phosphate ester resin prepared in Step A above, 2.30 g of dimethylethanolamine, and 74.0 g of Phenodur@ (ORegistered Trademark of Hoechst) PR612 phenolic resin (80 percent in butanol) were charged into to a 500 ml, 5- neck round bottom glass reactor, equipped with a nitrogen inlet, water cooled condenser, 250 mL dropping funnel, an agitator and an electrical heating mantle which was connected to a temperature control unit, and heated slowly at 90°C. The agitator was started as soon as the solid resin was molten. The mixture was kept at 90°C until a homogeneous solution was obtained. 200 g of deionized water were fed into the mixture within about 30 minutes at a temperature between 85°C and 95°C. After all the water had been added, the dispersion was stirred for an additional 30 minutes at 80°C. Then the resulting heat-curable formulation was cooled to about 30°C and bottled.

The resulting heat-curable formulation had a non-volatile content of about 46 weight percent, a Brookfield viscosity of about 80 mPa-s at 23°C and a pH value of about 6.1. Very tough and chemical resistant coatings were obtained when Bonder steel panels were coated with this formulation using a spiral wound bar (70 um) and curing at 200°C for 3 minutes.

Example 2 A. Epoxv Phosphate Ester Resin Synthesis 1898.4 g of D. E. R. 330 liquid epoxy resin with an EEW of 180 were charged to a 5 L double-jacketed steel reactor equipped with stirrer, oil heating and heat control unit; and the epoxy resin was heated to 120°C with stirring. Then 707.4 g of solid bisphenol-A

were charged to the reactor and mixed with the epoxy resin. The resulting reaction mixture was heated to 100°C and then 1.9 g of ethyl triphenyl phosphonium acetic acid acetate complex catalyst solution (herein"Catalyst A") were added to the reaction mixture and the reaction was allowed to exotherm. After the exotherm, 427.6 g of D. E. R. 662 solid epoxy resin with an EEW of 601 were then added to the reaction mixture and the resulting mixture was cooled to 110°C.

A mixture of 343.8 g of diethylene glycol, 49.6 g of o-phosphoric acid (85 percent) and 89.4 g of water were then added into the reactor. The resulting mixture was allowed to exotherm and to react at 145°C for approximately 2.5 hours. Then the resin was "flaked", that is, poured onto an aluminum foil as a thin film, and allowed to cool to room temperature at which it formed a solid block. The solid block of material can be broken up into any desired size pieces and advantageously used as a solid in various formulations and compositions.

The resulting solid product had the following properties: An EEW of greater than 43000, a molecular weight (Mw) of 8308 and a solution viscosity of 980 cSt. (measured at 25°C in a solution of 40 weight percent in diethylene glycol monobutyl ether). The amount of unreacted diethylene glycol was determined to be 5.3 wt-percent, which corresponds to a consumption of 46 percent of the total amount of diethylene glycol.

B. Heat-curable Coatina Dispersion Formulation Preparation A stable heat-curable formulation was obtained according to the following procedure: A 70.56 g sample of the resin product obtained above in Step A, 7.84 g of Methylon* 75108 phenolic resin (Methylon is a trademark of Occidental Chemical Corporation), and 1.06 g of dimethylethanolamine were heated in a glass reactor equipped with a mechanical stirrer to a temperature of 115°C to 120°C and melted. The resulting mixture was allowed to homogenize with slow stirring for 30 minutes, after which the mixture was cooled to a temperature of 90°C to 95°C. 107.20 g of water were then added to the mixture in a period of 20 minutes with vigorous stirring. The resulting dispersion was stirred at 80°C for an additional hour and gradually cooled down to room temperature resulting in a heat-curable lacquer product having non-volatiles of 42 weight percent and a Brookfield viscosity of 56 mPa-s at 25°C.

C. Coated Substrates Tinplate panels of size 100 mm x 160 mm were coated with the lacquer product prepared above in Step B using a spiral wound bar (401lm). Then the coated panels were cured at 200°C for 10 minutes.

Cups with 4 corners at different radii (5 mm, 10 mm, 15 mm, 20 mm) were drawn from the cured panels and then the cups were subjected to sterilization tests in different aqueous media as described in Table I below. The results of the tests are shown in Table I below.

Table I Test # Test Example 1 Comparative Example A 1 non-volatiles (weight percent) 42. 0 24. 0 2 Brookfield viscosity at 25°C 56 54 (mPa s) 3 Thickness m 6. 0 3. 5 4 Solvent resistance (MEK double rubs) 60 >100 Formability (1111 best-9999 worst) 1111 6411 6 Chemical resistance in water (30 minutes 2111 7651 at 129°C 7 Chemical resistance in 3 percent salt (30 minutes at 121 °C 2111 s-7651 8 Chemical resistance in 3 percent acetic acid/2 percent salt (30 minutes at 121 °C 3211 s-7653s- 9 Chemical resistance in 2 percent lactic acid (30 minutes at 121 °C) 4222s 7664s- Abbreviations used for results in Tests 6 to 9: s-= very slight blush s = slight blush B= Blush S = Strong blush Formability ratings are measured in numbers consisting of four digits. Each of the four digits of the four digit number in Tests 5 to 9 in Table I above represents a rating of the state of one of the corners of the cup as observed after the cup is deep-drawn as follows: A smooth surface with no scratches is rated"1" ; slightly rough surface is rated"2" ; <BR> <BR> <BR> <BR> metal starting to show through coating is rated"3" ; whole section of coating missing length c 0.8 cm is rated"4" ; whole section of coating missing length 0.8 to 1 cm is rated"5" ; whole section of coating missing length 1.1 to 1.4 cm is rated"6" ; whole section of coating missing length 1.4 to 1.7 cm is rated"7" ; whole section of coating missing length 1.8 to 2.0 cm is

rated"8" ; total peel off is rated"9". The best rating would be 1111, and the worst rating would be 9999.

Example 3 1567.7 g of D. E. R. 330 liquid epoxy resin with an EEW of 179.2 were charged to a 5 L double-jacketed steel reactor equipped with stirrer, oil heating and heat control unit; and the epoxy resin was heated to 118°C with stirring. Then 587.8 g of solid bisphenol-A were charged to the reactor and mixed with the epoxy resin. The resulting reaction mixture was heated to 100°C and then 1.6 g of Catalyst A solution were added to the reaction mixture and the reaction was allowed to exotherm. After the exotherm the resulting mixture was cooled to 120°C.

A mixture of 244.2 g of diethylene glycol, 35.1 g of o-phosphoric acid (85 percent) and 63.50 g of water were then added to the reactor. Then the reactor was pressurized with nitrogen to about 6 bar and the mixture was allowed to exotherm hitting a peak exotherm temperature of 151°C, after which the reaction mix was kept at 145°C for an additional 2 hours. Then the resulting molten resin was flaked and allowed to cool to room temperature at which the resin formed a solid block.

The resulting solid product had the following properties: An EEW of greater than 43000, an Mw of 7772, a melt viscosity of 6.9 Pa-s at 150°C and a Mettler softening point of 94.3°C. The amount of unreacted diethylene glycol was determined to be about 5.5 weight percent, which corresponds to a consumption of 44 percent of the total amount of glycol.

Example 4 1450.6 g of D. E. R. 331 liquid epoxy resin with an EEW of 187.4 were charged to a 5 L double-jacketed steel reactor equipped with stirrer, oil heating and heat control unit; and the epoxy resin was heated to 116°C with stirring. Then 555.8 g of solid bisphenol-A were charged to the reactor and mixed with the epoxy resin. The resulting reaction mixture was heated to 100°C and then 1.4 g of Catalyst A solution were added to the reaction mixture and the reaction was allowed to exotherm. After the exotherm, the resulting mixture was cooled to 120°C.

A mixture of 206.4 g of diethylene glycol, 28.7 g of o-phosphoric acid (85 percent) and 60.10 g of water were then added to the reactor. Then the reactor was pressurized with nitrogen to about 6 bar and the mixture was allowed to exotherm. Then the

reaction mix was reacted for additionally approximately 2 hours at about 145°C after which the resin was flaked and allowed to cool to room temperature at which it formed-a solid block.

The resulting solid product had the following properties: An EEW of greater than 43000, an Mw of 7018, a solution viscosity of 1037 cSt percent (measured at 25°C in a solution of 40 weight percent in diethylene glycol monobutyl ether), a melt viscosity of 12.8 Pa-s at 150°C and a Mettler softening point of 101.8°C. The amount of unreacted diethylene glycol was determined to be 4.91 weight percent. This corresponds to a consumption of 45 of the total amount of glycol.

Example 5 1456.7 g of D. E. R. 331 liquid epoxy resin with an EEW of 187.4 were charged to a 5 L double-jacketed steel reactor equipped with stirrer, oil heating and heat control unit; and the epoxy resin was heated to 115°C with stirring. Then 558.1 g of solid bisphenol-A were charged to the reactor and mixed with the epoxy resin. The resulting reaction mixture was heated to 100°C and then 1.4 g of Catalyst A solution were added to the reaction mixture and the reaction was allowed to exotherm. After the exotherm, the resulting mixture was cooled to 120°C.

A mixture of 157.8 g of diethylene glycol, 28.81 g of o-phosphoric acid (85 percent) and 87.6 g of water were then added to the reactor. Then the reactor was pressurized with nitrogen to about 6 bar and the mixture was allowed to exotherm and kept at about 140°C for about two hours. Then the resulting product was flaked and allowed to cool to room temperature at which it formed a solid block of resin.

The resulting solid product had the following properties: An EEW of greater than 43000, an Mw of 7250, a solution viscosity of 1138 cSt percent (measured at 25°C in a solution of 40 weight percent in diethylene glycol monobutyl ether), a melt viscosity of 12.5 Pa-s at 150°C and a Mettler softening point of 104.2°C. The amount of unreacted diethylene glycol was determined to be 3.71 weight percent which corresponds to a consumption of 47 percent of the total amount of glycol.

Example 6 1465.8 g of D. E. R. 331 liquid epoxy resin with an EEW of 187.4 were charged to a 5 L double-jacketed steel reactor equipped with stirrer, oil heating and heat control unit; and the epoxy resin was heated to 120°C with stirring. Then 561.7 g of solid bisphenol-A

were charged to the reactor and mixed with the epoxy resin. The resulting reaction mixture was heated to 100°C and then 1.4 g of Catalyst A solution were added to the reaction mixture and the reaction was allowed to exotherm. After the exotherm, the resulting mixture was cooled to 120°C.

A mixture of 209.0 g of tetraethylene glycol, 28.9 g of o-phosphoric acid (85 percent) and 88.5 g of water were then added to the reactor. Then the reactor was pressurized with nitrogen to about 6 bar and the mixture was allowed to exotherm after which the reaction mix was kept at about 140°C for approximately two hours. Then the resulting product was flaked and allowed to cool to room temperature at which it formed a solid block of resin.

The resulting solid product had the following properties: An EEW of greater than 43000, an Mw of 7062, a solution viscosity of 1003 cSt (measured at 25°C in a solution of 40 weight percent in diethylene glycol monobutyl ether), a melt viscosity of 8.9 Pa-s at 150°C and a Mettler softening point of 96.3°C. The amount of unreacted glycol was determined to be 5.1 weight percent which corresponds to a consumption of 43 percent of the total amount of glycol used.

Example 7 1486.1 g of D. E. R. 331 liquid epoxy resin with an EEW of 187.4 were charged to a 5 L double-jacketed steel reactor equipped with an oil heating and heat control unit; and the epoxy resin was heated to 120°C. Then 569.5 g of solid bisphenol-A were charged to the reactor and mixed with the epoxy resin. The resulting reaction mixture was heated to 100°C and then 1.4 g of Catalyst A solution were added to the reaction mixture and the reaction was allowed to exotherm. After the exotherm, the resulting mixture was cooled to 120°C.

A mixture of 161.2 g of tetraethylene glycol, 29.3 g of phosphoric acid (85 percent) and 89.6 g of water were then added to the reactor. Then the reactor was pressurized with nitrogen to about 6 bar and the mixture was allowed to exotherm. The reaction mix was kept at about 140°C for two hours, then the resin was flaked and allowed to cool to room temperature at which it formed a solid block of resin.

The resulting solid product had the following properties: An EEW of greater than 43000, an Mw of 6967, a solution viscosity of 1020 cSt (measured at 25°C in a solution of 40 weight percent in diethylene glycol monobutyl ether), a Mettler softening point of 103.3°C and a melt viscosity of 10.2 at 150°C. The amount of unreacted glycol was

determined to be approximately 4.0 weight percent which corresponds to a consumption of about 43 percent of the total amount of glycol used.

Example 8 1573.9 g of D. E. R. 331 liquid epoxy resin with an EEW of 187.4 were charged to a 5 L double-jacketed steel reactor equipped with stirrer, oil heating and heat control unit; and the epoxy resin was heated to 115°C with stirring. Then 603.1 g of solid bisphenol-A were charged to the reactor and mixed with the epoxy resin. The resulting reaction mixture was heated to 100°C and then 1.5 g of Catalyst A solution were added to the reaction mixture and the reaction was allowed to exotherm. After the exotherm, the resulting mixture was cooled to 120°C.

A mixture of 224.4 g of polyethylene glycol 200,31 g of o-phosphoric acid (85 percent) and 94.9 g of water were then added to the reactor. Then the reactor was pressurized with nitrogen to about 6 bar and the mixture was allowed to exotherm. The reaction mix was kept at 140°C for approximately 2 hours and 40 minutes, after which the resulting product was flaked and allowed to cool to room temperature at which it formed a solid block of resin The resulting solid product had the following properties: An EEW of greater than 43000, an Mw of 6467 and a solution viscosity of 888 cSt (measured at 25°C in a solution of 40 weight percent in diethylene glycol monobutyl ether), a Mettler softening point of 94.5°C and a melt viscosity of 4.64 at 150°C. The amount of unreacted glycol was determined to be approximately 5.0 weight percent which corresponds to a consumption of about 44 percent of the total amount of glycol originally present.

Example 9 1644.7 g of D. E. R. 331 liquid epoxy resin with an EEW of 187.4 were charged to a 5 L double-jacketed steel reactor equipped with stirrer, oil heating and heat control unit; and the epoxy resin was heated to 115°C with stirring. Then 630.7 g of solid bisphenol-A were charged to the reactor and mixed with the epoxy resin. The resulting reaction mixture was heated to 100°C and then 1.5 g of Catalyst A solution were added to the reaction mixture and the reaction was allowed to exotherm. After the exotherm, the resulting mixture was cooled to 120°C.

A mixture of 234.5 g of polyethylene glycol 400,32.4 g of o-phosphoric acid (85 percent) and 98.9 g of water were then added to the reactor. Then the reactor was

pressurized with nitrogen to about 6 bar and the mixture was allowed to exotherm. The reaction mix was kept at about 130°C for about 2.5 hours. Then the resulting product was flaked and allowed to cool to room temperature at which it formed a solid block of resin.

The resulting solid product had the following properties: An EEW of greater than 43000, an Mw of 6963 and a solution viscosity of 1048 cSt (measured at 25°C in a solution of 40 weight percent in diethylene glycol monobutyl ether), a Mettler softening point of 100.4°C, a melt viscosity of 8.32 Pa-s at 150°C. The amount of residual glycol was determined to be about 5.2 weight percent, which corresponds to a consumption of about 42 percent of the total amount of glycol originally present.

Example 10 1459.5 g of D. E. R. 331 liquid epoxy resin with an EEW of 187.4 were charged to a 5 L double-jacketed steel reactor equipped with stirrer, oil heating and heat control unit; and the epoxy resin was heated to 115°C with stirring. Then 595.1 g of solid bisphenol-A were charged to the reactor and mixed with the epoxy resin. The resulting reaction mixture was heated to 100°C and then 1.4 g of Catalyst A solution were added to the reaction mixture and the reaction was allowed to exotherm. After the exotherm, the resulting mixture was cooled to 120°C.

A mixture of 210.2 g of triethylene glycol, 25.7 g of o-phosphoric acid (85 percent) and 69.8 g of water were then added to the reactor. Then the reactor was pressurized with nitrogen to about 6 bar and the mixture was allowed to exotherm. The reaction mix was kept at about 140°C for about 2.5 hours, then the resulting product was flaked and allowed to cool to room temperature at which it formed a solid block of resin.

The resulting product had the following properties: An EEW of greater than 43000, an Mw of 8163, a solution viscosity of 1264 cSt (measured at 25°C in a solution of 40 weight percent in diethylene glycol monobutyl ether), a Mettler softening point of 100.2°C and a melt viscosity of 13.44 Pa-s at 150°C. The amount of unreacted glycol was determined to be 5.0 weight percent which corresponds to a consumption of 44 percent of the total amount of glycol initially present.

Example 11 1459.5 g of D. E. R. 331 liquid epoxy resin with an EEW of 187.4 were charged to a 5 L double-jacketed steel reactor equipped with stirrer, oil heating and heat control unit; and the epoxy resin was heated to 115°C with stirring. Then 595.1 g of solid bisphenol-A

were charged to the reactor and mixed with the epoxy resin. The resulting reaction mixture was heated to 100°C and then 1.5 g of Catalyst A solution were added to the reaction mixture and the reaction was allowed to exotherm. After the exotherm, the resulting mixture was cooled to 120°C.

A mixture of 210.2 g of tetraethylene glycol, 25.7 g of o-phosphoric acid (85 percent) and 69.8 g of water were then added to the reactor. Then the reactor was pressurized with nitrogen to about 6 bar and the mixture was allowed to exotherm. Then the reaction mix was kept at 140°C for approximately 2.5 hours after which the resulting product was flaked and allowed to cool to room temperature at which it formed a solid block of resin.

The resulting solid product had the following properties: An EEW of greater than 43000, an Mw of 8172, a solution viscosity of 1307 cSt (measure at 25°C in a solution of 40 weight percent in diethylene glycol monobutyl ether), a Mettler softening point of 102.2°C and a melt viscosity of 19.2 Pa-s at 150°C. The amount of unreacted glycol was determined to be 4.9 weight percent, which corresponds to a consumption of 45 percent of the total amount of glycol initial present.

Example 12 1619.2 g of D. E. R. 331 liquid epoxy resin with an EEW of 187.4 were charged to a 5 L double-jacketed steel reactor equipped with stirrer, oil heating and heat control unit; and the epoxy resin was heated to 120°C with stirring. Then 660.2 g of solid bisphenol-A were charged to the reactor and mixed with the epoxy resin. The resulting reaction mixture was heated to 100°C and then 1.6 g of Catalyst A solution were added to the reaction mixture and the reaction was allowed to exotherm. After the exotherm, the resulting mixture was cooled to 120°C.

A mixture of 233.2 g of polyethylene glycol 400,28.5 g of o-phosphoric acid (85 percent) and 77.3 g of water were then added to the reactor. Then the reactor was pressurized with nitrogen to about 6 bar and the mixture was allowed to exotherm. The reaction mix was kept at about 135°C for an additional two hours after which the resulting product was flaked and allowed to cool to room temperature at which it formed a solid block of resin.

The resulting product had the following properties: An EEW of greater than 43000, an Mw of 8811, a solution viscosity of 1371 cSt (measured at 25°C in a solution of 40 weight percent in diethyiene glycol monobutyl ether), a Mettler softening point of 104.8°C and a melt viscosity of 11.52 Pa-s at 150°C. The amount of unreacted glycol was

determined to be 5.4 weight percent, which corresponds to a consumption of glycol of 40 percent of the total amount of glycol initially present.

Example 13 1552.0 g of D. E. R. 331 liquid epoxy resin with an EEW of 187.4 were charged to a 5 L double-jacketed steel reactor equipped with stirrer, oil heating and heat control unit; and the epoxy resin was heated to 120°C with stirring. Then 545.6 g of solid bisphenol-A were charged to the reactor and mixed with the epoxy resin. The resulting reaction mixture was heated to 100°C and then 1.5 g of Catalyst A solution were added to the reaction mixture and the reaction was allowed to exotherm. After the exotherm, the resulting mixture was cooled to 120°C.

A mixture of 216.9 g of triethylene glycol, 35 g of o-phosphoric acid (85 percent) and 95.12 g of water were then added to the reactor. Then the reactor was pressurized with nitrogen to about 6 bar and the mixture was allowed to exotherm. The reaction mixture was kept at about 140°C for about two hours after which the resulting product was flaked and allowed to cool to room temperature at which it formed a solid block of resin.

The resulting solid product had the following properties: An EEW of greater than 43000, an Mw of 5397, a solution viscosity of 715 cSt (measured at 25°C in a solution of 40 weight percent in diethylene glycol monobutyl ether), a Mettler softening point of 90.5°C and a melt viscosity of 5.3 Pa-s at 150°C. The amount of unreacted glycol was 4.73 weight percent which corresponds to a consumption of glycol of 47 percent of the total amount of glycol initially present.

Example 14 1486.7 g of D. E. R. 331 liquid epoxy resin with an EEW of 187.4 were charged to a 5 L double-jacketed steel reactor equipped with stirrer, oil heating and heat control unit; and the epoxy resin was heated to 120°C with stirring. Then 522.6 g of solid bisphenol-A were charged to the reactor and mixed with the epoxy resin. The resulting reaction mixture was heated to 100°C and then 1.4 g of Catalyst A solution were added to the reaction mixture and the reaction was allowed to exotherm. After the exotherm, the resulting mixture was cooled to 120°C.

A mixture of 158.14 g of triethylene glycol, 33.53 g of o-phosphoric acid (85 percent) and 91.14 g of water were then added to the reactor. Then the reactor was

pressurized with nitrogen to about 6 bar and the mixture was allowed to exotherm. The reaction mix was kept at about 140°C for about two hours later, then the product was flaked and allowed to cool to room temperature at which it formed a solid block of resin.

The resultant product had the following properties: An EEW of greater than 43000, an Mw of 5650, a solution viscosity of 862 cSt (measured at 25°C in a solution of 40 weight percent in diethylene glycol monobutyl ether), a Mettler softening point of 98°C and a melt viscosity of 6.4 Pa-s at 150°C. The amount of unreacted glycol was approximately 3.58 weight percent, which corresponds to a consumption of glycol of about 49 percent of the total amount of glycol initially present.

Example 15 1486.7 g of D. E. R. 331 liquid epoxy resin with an EEW of 187.4 were charged to a 5 L double-jacketed steel reactor equipped with stirrer, oil heating and heat control unit; and the epoxy resin was heated to 115°C with stirring. Then 522.6 g of solid bisphenol-A were charged to the reactor and mixed with the epoxy resin. The resulting reaction mixture was heated to 100°C and then 1.4 g of Catalyst A solution were added to the reaction mixture and the reaction was allowed to exotherm. After the exotherm, the resulting mixture was cooled to 120°C.

A mixture of 110.5 g of triethylene glycol, 33.53 g of phosphoric acid (85 percent) and 91.14 g of water were then added to the reactor. Then the reactor was pressurized with nitrogen to 6 bar and the mixture was allowed to exotherm and kept at about 140°C for about 2.5 hours after which the product was flaked and allowed to cool to room temperature at which it formed a solid resin block.

The resulting product had the following properties: An EEW greater than 43000, an Mw of 5823, a solution viscosity of 932 cSt (measured at 25°C in a solution of 40 weight percent in diethylene glycol monobutyl ether), a Mettler softening point of 103.3°C and a melt viscosity of 10.9 Pa-s at 150°C. The amount of unreacted glycol was found to be about 2.39 weight percent, which corresponds to a consumption of glycol of about 52 percent of the total amount of glycol initially present.

Example 16 2667.0 g of D. E. R. 331 liquid epoxy resin with an EEW of 187.2 were charged to a 5 L double-jacketed steel reactor equipped with stirrer, oil heating and heat control unit; and the epoxy resin was heated to 115°C with stirring. Then 935.5 g of solid bisphenol-A

were charged to the reactor and mixed with the epoxy resin. The resulting reaction mixture was heated to 100°C and then 2.57 g of Catalyst A solution were added to the reaction mixture and the reaction was allowed to exotherm. After the exotherm, the resulting mixture was cooled to 120°C.

A mixture of 337.3 g of triethylene glycol, 118.2 g of phosphoric acid (85 percent) and 104.4 g of water were then added to the reactor. Then the reactor was pressurized with nitrogen to about 3.6 bar and the mixture was allowed to exotherm. The resin mix was kept at about 145°C for about one hour after which the resulting product was flaked and allowed to cool to room temperature at which it formed a solid block of resin.

The resulting solid product had the following properties: An EEW of greater than 43000, an Mw of 10560, a solution viscosity of 850 cSt (measured at 25°C in a solution of 40 weight percent in diethylene glycol monobutyl ether) and a Mettler softening point of 104.6°C. The amount of unreacted glycol was determined to be about 4.6 weight percent, which corresponds to a consumption of about 45 percent of the total amount of glycol initially present.

Example 17 1853.4 g of D. E. R. 331 liquid epoxy resin with an EEW of 188.4 were charged to a 5 L double-jacketed steel reactor equipped with stirrer, oil heating and heat control unit; and the epoxy resin was heated to 115°C with stirring. Then 650.4 g of solid bisphenol-A were charged to the reactor and mixed with the epoxy resin. The resulting reaction mixture was heated to 100°C and then 1.9 g of Catalyst A solution were added to the reaction mixture and the reaction was allowed to exotherm. After the exotherm, 144.2 g of stearic acid as a capping agent for the epoxy were added to the reaction mixture with an additional 3.7 g of Catalyst A solution and the mixture was reacted at 180°C for an additional two hours. The mixture was then cooled to 120°C. The EEW of the resulting resin increased to 1011 during this time.

A mixture of 213.0 g of triethylene glycol, 27.5 g of phosphoric acid (85 percent) and 84.0 g of water were then added to the reactor. Then the reactor was pressurized with nitrogen to about 6 bar and the mixture was allowed to exotherm. The reaction mix was then kept at about 140°C for approximately two hours after which the resulting product was flaked and allowed to cool to room temperature at which it formed a solid block of resin.

The resulting solid product had the following properties: An EEW of greater than 43000, an Mw of 7424 and a solution viscosity of 879 cSt (measured at 25°C in a solution of 40 weight percent in diethylene glycol monobutyl ether).

Example 18 1487.3 g of D. E. R. 331 liquid epoxy resin with an EEW of 187.4 were charged to a 5 L double-jacketed steel reactor equipped with stirrer, oil heating and heat control unit; and the epoxy resin was heated to 120°C with stirring. Then 606.8 g of solid bisphenol-A were charged to the reactor and mixed with the epoxy resin. The resulting reaction mixture was heated to 100°C and then 1.6 g of Catalyst A solution were added to the reaction mixture and the reaction was allowed to exotherm. After the exotherm, 483 g of benzoic acid as a capping agent for the epoxy were added to the reaction mixture and allowed to react for 15 minutes. Then an additional 1 g of Catalyst A solution were added to the reaction mixture and the reaction proceeded for an additional 15 minutes. Then the mixture was cooled to 120°C. The EEW of the resulting resin was measured and found to be 987 at that time.

A mixture of 170.0 g of triethylene glycol, 22.52 g of o-phosphoric acid (85 percent) and 61.0 g of water were then added to the reaction mixture. Then the reactor was pressurized with nitrogen to about 6 bar and the mixture was allowed to exotherm and the reaction mix was kept at 140°C for about 1 hour 40 minutes, after which the resulting product was flaked and allowed to cool to room temperature at which it formed a solid block of resin.

The resulting solid product had the following properties: An EEW of greater than 43000, an Mw of 11824, a solution viscosity of 1686 cSt (measured at 25°C in a solution of 40 weight percent in diethylene glycol monobutyl ether), a Mettler softening point of 109.2°C and a melt viscosity of 28.8 Pa-s at 150°C. The amount of unreacted glycol was determined to be about 4.17 weight percent, which corresponds to a consumption of about 30 percent of the total amount of glycol initially present.

Example 19 1466.4 g of D. E. R. 331 liquid epoxy resin with an EEW of 187.4 were charged to a 5 L double-jacketed steel reactor equipped with stirrer, oil heating and heat control unit; and the epoxy resin was heated to 115°C with stirring. Then 533.6 g of solid bisphenol-F were charged to the reactor and mixed with the epoxy resin. The resulting reaction mixture

was heated to 100°C and then 1.5 g of Catalyst A solution were added to the reaction mixture and the reaction was allowed to exotherm. After the exotherm, the resulting mixture was cooled to 120°C.

A mixture of 155.71 g of triethylene glycol, 25.00 g of o-phosphoric acid (85 percent) and 67.9 g of water were then added to the reactor. Then the reactor was pressurized with nitrogen to about 6 bar and the mixture was allowed to exotherm. Then the reaction mix was kept at approximately 140°C for about 2 hours after which the resulting product was flaked and allowed to cool to room temperature at which it formed a solid block of resin.

The resulting product had the following properties: An EEW of greater than 43000, an Mw of 11568 and a solution viscosity of 1218 cSt (measured at 25°C in a solution of 40 weight percent in diethylene glycol monobutyl ether). The amount of unreacted glycol was determined to be about 3.82 weight percent, which corresponds to a consumption of glycol of about 45 percent of the total amount of glycol initially present.

Example 20 1549.5 g of D. E. R. 331 liquid epoxy resin with an EEW of 188.4 were charged to a 5 L double-jacketed steel reactor equipped with stirrer, oil heating and heat control unit; and the epoxy resin was heated to 115°C with stirring. Then 484.4 g of solid bisphenol-F were charged to the reactor and mixed with the epoxy resin. The resulting reaction mixture was heated to 100°C and then 1.4 g of Catalyst A solution were added to the reaction mixture and the reaction was allowed to exotherm. After the exotherm, the resulting mixture was cooled to 120°C.

A mixture of 160.8 g of triethylene glycol, 34.76 g of o-phosphoric acid (85 percent) and 105.9 g of water were then added to the reactor. Then the reactor was pressurized with nitrogen to 6 bar and the mixture was allowed to exotherm. Then the reaction mix was kept at about 140°C for about 2.5 hours after which the reaction product was flaked and allowed to cool to room temperature at which it formed a solid block of resin.

The resulting solid product had the following properties: An EEW of greater than 43000, an Mw of 6111 and a solution viscosity of 627 cSt (measured at 25°C in a solution of 40 weight percent in diethylene glycol monobutyl ether).

Example 21 1393.0 g of D. E. R. 331 liquid epoxy resin with an EEW of 188.4 were charged to a 5 L double-jacketed steel reactor equipped with stirrer, oil heating and heat control unit; and the epoxy resin was heated to 115°C with stirring. Then 503.4 g of solid bisphenol-F were charged to the reactor and mixed with the epoxy resin. The resulting reaction mixture was heated to 100°C and then 1.3 g of Catalyst A solution were added to the reaction mixture and the reaction was allowed to exotherm. After the exotherm, the resulting mixture was cooled to 120°C.

A mixture of 148.0 g of triethylene glycol, 23.7 g of phosphoric acid (85 percent) and 72.4 g of water were then added to the reactor. Then the reactor was pressurized with nitrogen to about 6 bar and the mixture was allowed to exotherm. Then the reaction mix was kept at about 140°C for about 2 hours after which the resulting product was flaked and allowed to cool to room temperature at which it formed a solid block of resin.

The resulting solid product had the following properties: An EEW of greater than 43000 and an Mw of 10170.

Example 22 2199.0 g of D. E. R. 331 liquid epoxy resin with an EEW of 187.2 were charged to a 5 L double-jacketed steel reactor equipped with stirrer, oil heating and heat control unit; and the epoxy resin was heated to 115°C with stirring. Then 771.3 g of solid bisphenol-A were charged to the reactor and mixed with the epoxy resin. The resulting reaction mixture was heated to 100°C and then 2.11 g of Catalyst A solution were added to the reaction mixture and the reaction was allowed to exotherm. After the exotherm, the resulting mixture was cooled to 132°C.

After the mixture was cooled to 132°C, 307.10 g of triethylene glycol were added to the mixture. At 118°C, a mixture of 48.10 g of o-phosphoric acid (85 percent) and 85.00 g of water were then added to the reactor. Then the reactor was pressurized with nitrogen to 2.8 bar and the mixture was allowed to exotherm. The reaction mix was kept at about 150°C for about 50 minutes after which the resulting product was flaked and allowed to cool to room temperature at which it formed a solid block of resin.

The resulting solid product had the following properties: An EEW of greater than 43000, an Mw of 8125, a Mettler softening point of 103.3°C and a melt viscosity of 10.2 Pa-s at 150°C.

Example 23 3126.9 g of D. E. R. 331 liquid epoxy resin with an EEW of 188.4 were charged to a 5 L double-jacketed steel reactor equipped with stirrer, oil heating and heat control unit; and the epoxy resin was heated to 115°C with stirring. Then 1110.8 g of solid bisphenol-A were charged to the reactor and mixed with the epoxy resin. The resulting reaction mixture was heated to 100°C and then 3.05 g of Catalyst A solution were added to the reaction mixture and the reaction was allowed to exotherm. After the exotherm, the resulting mixture was cooled to 120°C.

A mixture of 437.90 g of triethylene glycol, 68.60 g of o-phosphoric acid (85 percent) and 121.40 g of water were then added to the reactor. Then the reactor was pressurized with nitrogen to 6 bar and the mixture was allowed to exotherm. The mix was kept at about 145°C for approximately 2.5 hours. Then the resulting product was flaked and allowed to cool to room temperature at which it formed a solid block of resin.

The resulting solid product had the following properties: An EEW of greater than 43000, an Mw of 6511 and a solution viscosity of 866 cSt (measured at 25°C in a solution of 40 weight percent in diethylene glycol monobutyl ether).

Example 24 3241.8 g of D. E. R. 331 liquid epoxy resin with an EEW of 188.4 were charged to a 5 L double-jacketed steel reactor equipped with stirrer, oil heating and heat control unit; and the epoxy resin was heated to 115°C with stirring. Then 1151.6 g of solid bisphenol-A were charged to the reactor and mixed with the epoxy resin. The resulting reaction mixture was heated to 100°C and then 3.16 g of Catalyst A solution were added to the reaction mixture and the reaction was allowed to exotherm. After the exotherm, the resulting mixture was cooled to 120°C.

A mixture of 453.7 g of triethylene glycol, 71.12 g of o-phosphoric acid (85 percent) and 125.90 g of water were then added to the reactor. Then the reactor was pressurized with nitrogen to 6 bar and the mixture was allowed to exotherm. The reaction mix was kept at 150°C for 2.5 hours after which the resulting product was flaked and allowed to cool to room temperature at which it formed a solid block of resin.

The resulting solid product had the following properties: An EEW of greater than 43000, an Mw of 5957 and a solution viscosity of 808 cSt (measured at 25°C in a solution of 40 weight percent in diethylene glycol monobutyl ether).

Example 25 3378.6 g of D. E. R. 331 liquid epoxy resin with an EEW of 185.8-were charged to a 5 L double-jacketed steel reactor equipped with stirrer, oil heating and heat control unit; and the epoxy resin was heated to 115°C with stirring. Then 1202.6 g of solid bisphenol-A were charged to the reactor and mixed with the epoxy resin. The resulting reaction mixture was heated to 100°C and then 3.27 g of Catalyst A solution were added to the reaction mixture and the reaction was allowed to exotherm. After the exotherm, the resulting mixture was cooled to 120°C.

A mixture of 473.10 g of triethylene glycol, 74.16 g of phosphoric acid (85 percent) and 131.30 g of water were then added to the reactor. Then the reactor was pressurized with nitrogen to 2.2 bar and the mixture was allowed to exotherm. The reaction mix was kept at about 148°C for approximately 2 hours and 15 minutes after which the resulting product was flaked and allowed to cool to room temperature at which it formed a solid block of resin.

The resulting solid product had the following properties: An EEW of greater than 43000, an Mw of 7570 and a solution viscosity of 818 cSt (measured at 25°C in a solution of 40 weight percent in diethylene glycol monobutyl ether).

Example 26 4647.2 g of D. E. R. 331 liquid epoxy resin with an EEW of 188.3 were charged to a 10 L double-jacketed steel reactor equipped with stirrer, oil heating and heat control unit; and the epoxy resin was heated to 115°C with stirring. Then 1639.6 g of solid bisphenol-A were charged to the reactor and mixed with the epoxy resin. The resulting reaction mixture was heated to 100°C and then 4.50 g of Catalyst A solution were added to the reaction mixture and the reaction was allowed to exotherm. After the exotherm, the resulting mixture was cooled to 120°C.

After the mixture has been cooled to 120°C, a mixture of 661.30 g of triethylene glycol, 207.20 g of o-phosphoric acid (85 percent) and 130.00 g of water were then added to the reactor. Then the reactor was pressurized with nitrogen to 2.9 bar and the mixture was allowed to exotherm. The reaction mix was kept at about 150°C for about one hour after which the resulting product was flaked and allowed to cool to room temperature at which it formed a solid block of resin.

The resulting solid product had the following properties: An EEW of greater than 43000, an Mw of 7059, a solution viscosity of 813 cSt (measured at 25°C in a solution of 40 weight percent in diethylene glycol monobutyl ether), a Mettler softening point of 99.8°C and a melt viscosity of 11.2 Pa-s at 150°C.

Example 27 3712.2 g of D. E. R. 331 liquid epoxy resin with an EEW of 187.8 were charged to a 10 L double-jacketed steel reactor equipped with stirrer, oil heating and heat control unit; and the epoxy resin was heated to 115°C with stirring. Then 1300.9 g of solid bisphenol-A were charged to the reactor and mixed with the epoxy resin. The resulting reaction mixture was heated to 100°C and then 3.58 g of Catalyst A solution were added to the reaction mixture and the reaction was allowed to exotherm. After the exotherm, the resulting mixture was cooled to 120°C.

After the mixture had been cooled to 120°C, a mixture of 527.4 g of triethylene glycol, 240.9 g of o-phosphoric acid (85 percent) and 94.70 g of water were then added to the reactor. Then the reactor was pressurized with nitrogen to about 3.0 bar and the mixture was allowed to exotherm. The reaction mix was kept at about 150°C for about one hour after which the resulting product was flaked and allowed to cool to room temperature at which it formed a solid block of resin.

The resulting solid product had the following properties: An EEW of greater than 43000, an Mw of 6307, a solution viscosity of 745 cSt (measured at 25°C in a solution of 40 weight percent in diethylene glycol monobutyl ether), a Mettler softening point of 97.3°C and a melt viscosity of 12.8 Pa-s at 150°C.

Example 28 In this example an aqueous epoxy phosphate ester resin dispersion was prepared as follows: A 5 L double-jacketed, oil heated steel reactor, equipped with a stirrer and heat control unit, was heated to a reactor inside temperature between 120°C and 130°C.

Then 3532.0 g of solid epoxy phosphate ester resin prepared in Example 23 were slowly added to the reactor and melted in the reactor. Then the reactor temperature was cooled to 119°C. 53.0 g of dimethylethanolamine were then added to the reactor. The reactor was subsequently cooled to 115°C and then 5298.0 g of water were slowly added to the reactor.

After the addition of the water was completed, the resulting dispersion was allowed to cool to a temperature of less than 80°C after which the dispersion was bottled.

A low viscous, stable, dispersion resulted with 40.0 weight percent non- volatiles.

Example 29 In this example an aqueous epoxy phosphate ester dispersion was prepared as follows: The heating mantle of a double-jacketed, oil heated steel reactor, equipped with a stirrer and heat control unit, was heated to a reactor inside temperature below 115°C.

Then 4100 g of solid epoxy phosphate ester resin prepared in Example 24 were slowly added to the reactor and melted in the reactor. Then the reactor temperature was heated to 119°C and 61.5 g of dimethylethanolamine were added to the reactor. The reactor was subsequently cooled to 112°C and then 6150 g of water were slowly added to the reactor.

After the addition of the water was completed the resulting dispersion was allowed to cool to a temperature below 80°C and then the dispersion was bottled.

A stable, low viscous dispersion resulted, having 40 weight percent non- volatiles.

Example 30 In this example an aqueous epoxy phosphate ester resin dispersion was prepared as follows: A 5 L double-jacketed, oil heated steel reactor, equipped with a stirrer, was heated to a reactor inside temperature below 130°C. Then 3657 g of solid epoxy phosphate ester resin prepared in Example 25 were slowly added to the reactor and melted in the reactor. Then the reactor temperature was cooled to 117°C. 54.9 g of dimethylethanolamine were then added to the reactor. The reactor was subsequently cooled to 105°C and then 5485.5 g of water were slowly added to the reactor. After the addition of the water was completed, the resulting dispersion was allowed to cool to a temperature of less than 80°C after which the dispersion was bottled.

A stable, low viscous dispersion resulted with 39.15 weight percent non- volatiles.

Example 31 In this example an aqueous epoxy phosphate ester resin dispersion was prepared as follows: A double-jacketed, oil heated steel reactor, equipped with a stirrer and heat control unit, was heated to a reactor inside temperature of about 120°C. Then 4000.0 g of solid epoxy phosphate ester resin prepared in Example 26 were slowly added to the reactor and melted in the reactor. Then the reactor temperature was cooled to 118°C. 120.0 g of dimethylethanolamine were then added to the reactor. The reactor was subsequently cooled to 115°C and then water was slowly added to the reactor within approximately 2 hours and 15 minutes, with the temperature being in the range of approximately 90°C to 100°C. After the addition of the water was completed, the resulting dispersion was bottled.

A low viscous, stable, dispersion resulted with 28.4 weight percent non- volatiles was obtained, having a pH of 7.1 and a Brookfield viscosity of 32 mua-s at 25°C.

Example 32 In this example an aqueous epoxy phosphate ester resin dispersion was prepared as follows: A 10 L double-jacketed, oil heated steel reactor, equipped with a stirrer and heat control unit, was heated to a reactor inside temperature between 120°C and 130°C.

Then 2000.0 g of solid epoxy phosphate ester resin prepared in Example 27 were slowly added to the reactor and melted in the reactor. Then the reactor temperature was cooled to 120°C. 87.0 g of dimethylethanolamine were then added to the reactor. The reactor was subsequently cooled to 119°C and then water was slowly added to the reactor within about 2 hours and 40 minutes, during which the temperature was kept between 90°C and 100°C.

After the addition of the water was completed, the resulting dispersion was bottled.

A low viscous, stable, dispersion resulted with 23.5 weight percent non- volatiles, having a pH of 7.1 and a Brookfield viscosity of 38 mPa-s at 25°C.

Example 33 In this example a heat-curable formulation using an epoxy phosphate ester dispersion was prepared as follows: 9.2 g of Cymel 328 methoxymethyl melamine hardener were mixed with 4.6 g of water at ambient temperature to form a solution of the hardener dissolve in water. Then

80 g of the aqueous epoxy phosphate ester resin dispersion of Example 30 were added to the aqueous Cymel 328 solution and thoroughly mixed together. A stable, low viscous dispersion resulted.

Example 34 In this example a heat-curable, stable formulation was obtained according to the following procedure: 43.20 g of the solid epoxy phosphate ester resin prepared in Step A of Example 2 and 2.16 g of Atsurf 108 polymeric surfactant were heated in a glass reactor equipped with a mechanical stirrer to a temperature of 115°C to 120°C and melted in the reactor. The molten mixture was allowed to homogenize with slow stirring for 30 minutes, after which the mixture was cooled to a temperature of 90-95°C. Then 0.65 g of dimethylethanolamine were added to the reactor. Fifteen minutes later, 2.40 g of Cymel 1123 methoxymethyl ethoxymethyl benzoguanamine hardener were added to the reactor.

The mixture was then allowed to homogenize under gentle agitation for 15 minutes. Then 111.59 g of water were added to the reaction mixture in a period of 20 minutes with vigorous stirring. The resulting dispersion was stirred at 90°C for an additional hour and gradually cooled down to room temperature to form a heat-curable lacquer.

The resulting heat-curable formulation had non-volatiles of 30 percent and a Brookfield viscosity of 28 mua-s at 25°C.

Panels were coated with the above lacquer product using a spiral wound bar applicator (40! lm) and then cured at 200°C for 5 minutes.

Cups with 4 corners at different radii (5 mm, 10 mm, 15 mm, and 20 mm) were drawn from the coated panels and then the layers were subjected to sterilization tests in different aqueous media as disclosed in Table II below. The results of the tests are shown inTable II below: Table II TestExample1Test# 11non-volatiles (weight percent) 30 2 Brookfield viscosity at 25°°C 28 3 Thickness (m) 4.3 4 Solvent resistance (MEK double rubs) 25 5 Formability (1111 best-9999 worst) 2111 6 Chemical resistance in water (30 minutes 2111 B at 129°C) 7 Chemical resistance in 3 percent salt (30 minutes at 121 °C) 2111 B 8 Chemical resistance in 3 percent acetic acid/2 percent salt (30 minutes at 121 °C) 2111 S 9 Chemical resistance in 2 percent lactic acid (30 minutes at 121 °C) 2222S

Abbreviations used for results in Tests 6 to 9: s-= very slight blush s = slight blush B = Blush S = Strong blush The ratings related to each of the four digits of the four-digit number in Tests 5 to 9 are as described in Example 2 above.

Example 35 In this example a stable, heat-curable formulation was obtained according to the following procedure: 45.60 g of the solid epoxy phosphate ester resin prepared in Step A of Example 2,2.28 g of the polymeric Atsurf 108 surfactant and 0.48 g of Methylon 75108 phenolic resin were heated in a glass reactor equipped with a mechanical stirrer to a temperature of 120°C to 125°C and melted in the reactor. The molten mixture was allowed to homogenize with slow stirring for 30 minutes, after which the mixture was cooled to a temperature of 90° to 95°C. Then 0.68 g of dimethylethanolamine were added to the reactor. Fifteen minutes later, 2.35 g of Cymes 1123 hardener were added to the reactor.

The mixture was then allowed to homogenize under gentle agitation for 15 minutes. Then 109.40 g of water were added to the reaction mixture in a period of 20 minutes with vigorous stirring. The resulting dispersion was stirred at 90°C for an additional hour and gradually cooled down to room temperature to form a heat-curable lacquer.

The resulting heat-curable formulation had a non-volatiles content of 30 percent and a Brookfield viscosity of 34 mPa s at 25°C.

Panels were coated with the above lacquer product using a spiral wound bar applicator (40 Rm) and then cured at 200°C for 5 minutes.

Cups with 4 corners at different radii (5 mm, 10 mm, 15 mm, 20 mm were drawn from the coated panels and the layers were subjected to sterilization tests in different aqueous media as described in Table III below. The results of the tests are shown in Table III below: Table III TestExample1Test# 1 non-volatiles (weight percent) 30 2 Brookfield viscosity at 259C (mPa-s) 34 3 Thickness m 5.3 4 Solvent resistance (MEK double rubs) 20 5 Formability (1111 best-9999 worst) 1111 6 Chemical resistance in water (30 minutes 2211 B art 129C 7 Chemical resistance in 3 percent salt (30 minutes at 121 °C) 2222B 8 Chemical resistance in 3 percent acetic acid/2 percent salt (30 minutes at 121 °C) 2111 B 9 Chemical resistance in 2 percent lactic acid (30 minutes at 121 °C) 2222S

Abbreviations used for results in Tests 6 to 9: s-= very slight blush s = slight blush B = Blush S = Strong blush The ratings related to each of the four digits of the four-digit number in Tests 5 to 9 are as described in Example 2 above.

Example 36 In this example a stable, heat-curable, formulation was obtained according to the following procedure: 55.00 g of the solid epoxy phosphate ester resin prepared in Step A of <BR> <BR> <BR> Example 2,27.13 g of Phenodur PR612 phenolic resin and 0.84 g of dimethylethanolamine were heated in a glass reactor equipped with a mechanical stirrer to a temperature of 120°C

to 125°C and melted in the reactor. The moiten mixture was aliowed to homogenize with slow stirring for 30 minutes, after which the mixture was cooled to a temperature of 90° to 95°C. 108.78 g of water were then added to the reaction mixture in a period of 20 minutes with vigorous stirring. The resulting dispersion was stirred at 90°C for an additional hour and gradually cooled down to room temperature.

The resulting heat-curable formulation had non-volatiles of 40 percent and a Brookfield viscosity of 40 mua-s at 25°C.

Example 37 In this example a stable, heat-curable, formulation was obtained according to the following procedure: 4.83 g of Cymel 328 and 2.92 g of water were weighed into a glass bottle.

The mixture was allowed to homogenize on a roller at ambient temperature for at least one hour. Then 92.25 g of the aqueous epoxy phosphate ester dispersion prepared in Example 28 were added to the glass bottle and the resulting mixture was thoroughly mixed on the roller at ambient temperature.

The prepared heat-curable formulation had non-volatiles of 41 percent and a Brookfield viscosity of 48 mPa-s at 25°C.

Panels were coated with the above prepared formulation or lacquer product using a spiral wound bar applicator (150 Rm) and then the coated panels were cured at 130°C for 15 minutes and then for an additional 30 minutes.

Mechanical and chemical tests were carried out on the cured panels, yielding the following results: Thickness: 27.8 um Solvent Resistance: greater than 100 Methyl Ethyl Ketone Double Rubs Indentation: 8.0 Rm Front Impact Resistance: 76 inch/pound Reverse Impact Resistance: 84 inch/pound Crosshatch & tape: 100 percent all right.

Example 38 In this example a stable, heat-curable, formulation was obtained according to the following procedure: 4.83 g of Cymel 373 methoxylmethyl methylol melamine hardener and 2.92 g of water were weighed into a glass bottle. The mixture was allowed to homogenize on a roller at ambient temperature for at least one hour. Then 92.25 g of the aqueous epoxy phosphate ester dispersion prepared in Example 28 were added to the glass bottle and the resulting mixture was thoroughly mixed on the roller at ambient temperature. The prepared formulation had non-volatiles of 41 percent and a Brookfield viscosity of 44 mua-s at 25°C.

Panels were coated with the above prepared formulation or lacquer product using a spiral wound bar applicator (150, um), and then the coated panels were are cured at 130°C for 15 minutes and then for an additional 30 minutes.

Mechanical and chemical tests were carried out on the cured panels, yielding the following results: Thickness: 27.9 um Solvent Resistance: greater than 100 Methyl Ethyl Ketone Double Rubs Indentation: 8.0 mm Front Impact Resistance: 136 inch/pound Reverse Impact Resistance: 160 inch/pound Crosshatch & tape: 100 percent all right.

Example 39 370 g of solid epoxy resin D. E. R. 664UE flakes, having an EEW of 895,370 g of crushed solid epoxy phosphate ester resin of Example 27 and 7.5 g of polyacrylic flow modifier Modaflow III (Modaflow is a trademark of Monsanto) were roughly mixed for 2 minutes without additional grinding.

The mixture was then extruded in a ZSK 30 extruder at a temperature between 80°C and 85°C. The extruded material was then finely ground to give a powder which passed through a sieve of 125 Rm mesh size.

The powder was then sprayed using a spray gun under conditions known in the art on a steel panel. The panel was then cured in an oven at 160°C for 20 minutes to yield a nice smooth clear coating having Acetone Double Rubs of 15 and passing an impact test according to ASTM D2794-93 at 20 inches/lbs.