WATER BORNE SOFT-FEEL COATING COMPOSITION

The invention relates to a water borne coating composition comprising a polyurethane and a polyisocyanate. The invention further relates to a kit of parts for preparation of the coating composition, to the use of the coating composition, to a process for applying a coating on a substrate, and to coated substrates.

A water borne coating composition of the above-mentioned type is known from United States patent application US 2004/0242765 A. This document describes aqueous polyurethane dispersions for producing coatings with a soft-feel effect. The aqueous coating composition comprises an aqueous formulation of a hydroxyl-containing polyurethane and a crosslinker. The crosslinker preferably is a polyisocyanate having free isocyanate groups.

In modern automobile interiors, soft-feel coatings are used to coat plastic parts such as instrument panels, door panels, arm rests, head rests, airbag covers, glove compartment covers, and center consoles. The soft-feel coatings are applied to convey a feeling of smoothness and luxury similar to that provided by leather or velvet. It is desirable that the soft-feel coatings, next to providing the required haptic perception, also have good chemical and mechanical resistance, such as suntan lotion resistance, hydrolysis resistance, and heat aging resistance. Improvement of the chemical and mechanical resistance of soft-feel coatings, at a given layer thickness, can be achieved by increasing the crosslink density and/or hardness of the coatings, e.g. by using a higher proportion of crosslinker and/or by employing binders having a higher hardness and/or a higher proportion of crosslinkable functional groups. However, it has been found that improvement of the chemical and mechanical resistance by taking such measures is accompanied by a deterioration of the soft-feel properties. Thus, a very good balance of the desired haptic properties and the chemical and mechanical resistance cannot be achieved with the known soft- feel coating compositions.

Accordingly, the invention seeks to provide a water borne coating composition from which soft-feel coatings can be produced, which coatings have an improved balance of chemical and mechanical resistance and soft-feel properties.

The invention now provides a water borne coating composition comprising a polyurethane and a polyisocyanate, wherein the composition further comprises a melamine polyol.

With the coating composition according to the invention it is possible to produce soft-feel coatings having an improved balance of chemical and mechanical resistance and soft-feel properties.

Suitable polyurethanes can be prepared according to generally known methods by reacting an aliphatic, alicyclic or aromatic di- or triisocyanate, one or more polyalcohols containing 2 to 6 hydroxyl groups and having a number average molecular weight up to 600, and/or a polyether or polyester diol having a number average molecular weight between about 400 and about 3,000. It is to be understood that the polyurethane present in the coating composition differs from the material formed by reaction of the polyisocyanate and the melamine polyol present in the coating composition. In order to achieve hydroxyl functionality in the resulting polyurethanes, a stoichiometric excess of the hydroxyl component can be used.

Carboxylic acid groups can be introduced into the polyurethanes by the co- reaction of hydroxycarboxylic acids. Dimethylol propionic acid, hydroxypivalic acid, and hydroxysteahc acid are examples of suitable hydroxycarboxylic acids.

Sulphonate groups or sulphonic acid groups can be introduced into a polyurethane, for example by co-reaction with isocyanates and with hydroxyl- or amine-functional compounds comprising at least one sulphonic acid group or sulphonate group, for example, 2-hydroxyethane sulphonic acid, the sodium salt

of 2-aminoethane sulphonic acid, 3-cyclohexylamino-i -propane sulphonic acid, the reaction product of sodium 5-sulphoisophthalate with an equivalent excess of diols, triols or epoxy compounds.

In one embodiment of the coating composition according to the invention, more than 50% of the sulphonic acid groups and carboxylic acid groups of the polyurethane are neutralized with a base. The polyurethane may also comprise non-ionic stabilizing groups. Alternatively or additionally, the polyurethane can be stabilized in an aqueous medium by external emulsifiers.

The polyurethanes can contain organic solvents for reduction of the viscosity. Suitable solvents are aromatic hydrocarbons such as toluene and xylene; alcohols such as ethanol, isopropanol, n-butanol, 2-butanol, hexanol, benzyl alcohol, and ketones such as methylethyl ketone, methylisobutyl ketone, methylamyl ketone, and ethylamyl ketone; esters such as butyl acetate, butyl propionate, ethoxyethyl propionate, ethylglycol acetate, butylglycol acetate, and methoxypropyl acetate; ethers such as diethylene glycol dimethyl ether, dipropylene glycol dimethyl ether, 2-methoxypropanol, 2-methoxybutanol, ethylene glycol monobutyl ether, propylene glycol monopropyl ether, propylene glycol monobutyl ether, dioxolane or mixtures thereof. Other suitable solvents are N-methyl-2-pyrrolidone, dimethyl carbonate, propylene carbonate, butyrolactone, caprolactone, etc.

Mixing the polyurethane with an aqueous medium can be done conveniently by adding water to the polyurethane solution or, alternatively, by adding the polyurethane solution to water, under agitation. If desired, the organic solvent content of the resulting polyurethane emulsion or dispersion can be reduced by distillation, optionally under reduced pressure. The coating composition generally contains at least 8% by weight of at least one polyurethane, calculated on the non-volatile content of the composition. In another embodiment, the amount of polyurethane is at least 12% by weight, or at least 20% by weight. Generally, the amount of polyurethane does not exceed 70% by weight, calculated on the non-volatile content of the composition. In another

embodiment, the amount of polyurethane is at most 60% by weight, or at most 50% by weight.

In one embodiment, the coating composition of the invention comprises at least two different polyurethanes. One of the polyurethanes may be essentially free of hydroxyl groups, whereas the other polyurethane may comprise a plurality of hydroxyl groups. In that case, the weight ratio of hydroxyl-free polyurethane to hydroxyl-functional polyurethane suitably is in the range of 95:5 to 60:40, based on non-volatile matter. The polyurethanes generally are present in the coating composition in the form of dispersed particles, i.e. polyurethane dispersions. Suitable polyurethanes are also commercially available in the form of aqueous dispersions, for example under the trade designation Bayhydrol® ex Bayer. Bayhydrol® PT 241 may be mentioned as a specific example of a suitable hydroxyl-functional polyurethane dispersion, Bayhydrol® PR 340 is an example of a non-functional polyurethane dispersion.

Suitable polyisocyanate crosslinkers include 1 ,6-diisocyanatohexane, isophorone diisocyanate, 2,4-toluene diisocyanate, 2,6-toluene diisocyanate, diphenyl methane-diisocyanate, 4,4'-bis(isocyanato-cyclohexyl)methane, 1 ,4- diisocyanatobutane, 1 ,5-diisocyanato-2,2-dimethyl pentane, 1 ,10-diisocyanato- decane, 1 ,4-diisocyanato-cyclohexane, 2,4-hexahydrotoluene diisocyanate, 2,6- hexahydrotoluene diisocyanate, norbornane diisocyanate, 1 ,3-xylene diisocyanate, 1 ,4-xylene diisocyanate, 1-isocyanato-3-(isocyanatomethyl) 1 - methylcyclohexane, m-α,α,α',α'-tetramethyl xylene diisocyanate. Also suitable as isocyanate curing agents are thisocyanates, for example, 1 ,8- diisocyanato-4-(isocyanatomethyl)octane, lysine thisocyanate, and adducts and oligomers of polyisocyanates, for instance, biurets, isocyanurates, allophanates, imino-oxadiazinediones, uretdiones, urethanes, and mixtures thereof. Examples of such oligomers and adducts are the adduct of 3 moles of toluene diisocyanate to 1 mole of trimethylol propane, the isocyanurate trimer of 1 ,6- diisocyanatohexane, the isocyanurate trimer of isophorone diisocyanate, the

uretdione dinner of 1 ,6-diisocyanatohexane, the biuret trimer of 1 ,6- diisocyanatohexane, the allophanate-modified trimer or higher oligomers of 1 ,6- diisocyanatohexane, the adduct of 3 moles of m-α,α,α',α'-tetramethyl xylene diisocyanate to 1 mole of trimethylol propane, and mixtures thereof.

The polyisocyanate crosslinker may comprise hydrophilic groups, for example, covalently bonded hydrophilic polyether moieties. Such polyisocyanates can be stirred in more easily by hand than hydrophobic polyisocyanates. Suitable polyether compounds for the modification of polyisocyanates are mono- and dihydric polyalkylene oxide polyether alcohols containing a statistical average of 3 to 35 ethylene oxide units. The hydrophilic polyisocyanates generally have an isocyanate functionality of 1.5 to 5 and a content of ethylene oxide units within the bound polyether chains of about 2 to 20% by weight. Examples of hydrophilic polyisocyanates are the reaction products of the isocyanurate trimers of 1 ,6-diisocyanatohexane and/or the isocyanurate trimers of isophorone diisocyanate and a methyl ether of polyethylene glycol; the reaction product of the adduct of m-α,α,α\α'-tetramethyl xylene diisocyanate (3 moles) to trimethylol propane (1 mole) and a methyl ether of polyethylene glycol. Alternatively, the polyisocyanate can be rendered hydrophilic by reaction with isocyanate-reactive compounds containing ionic groups, for example, the alkali metal salts of sulphonic acids containing at least one hydroxyl group or one isocyanate-reactive amine group. Another class of suitable polyisocyanate crosslinkers are polyisocyanates which contain external emulsifiers to facilitate their dissipation in water borne systems. Such polyisocyanate crosslinkers are commercially available from Rhodia. The amount of polyisocyanate in the coating composition generally is at least 5% by weight, based on the non-volatile content of the composition. In another embodiment, the amount of polyisocyanate is at least 10% by weight, or at least 15% by weight. The amount of polyisocyanate suitable is at most 30% by

weight, or at most 25% by weight, or at most 20% by weight, all based on the non-volatile content of the composition.

The melamine polyols used in the coating composition of the present invention are suitably prepared by reacting melamine aldehyde resins with diols. The melamine aldehyde resins themselves or melamine aldehyde resins ethehfied with monoalcohols, which are readily available on a commercial scale, are not melamine polyols.

The melamine polyols are generally prepared by reacting (a) at least one melamine aldehyde resin having the formula (I)

wherein Ri to Re are each selected from -H, CH ₂ OH, -CH ₂ OR ₇ , and may be the same or different, wherein R ₇ is a Ci to C ₅ alkyl group,

(b) at least one α,β-diol, α,γ-diol, or mixture thereof, and, optionally,

(c) a compound containing at least one functional group capable of reacting with the melamine aldehyde resin and, optionally, other functional groups, wherein the diol (b) and the resin (a) are reacted in such relative amounts that the ratio of the number of hydroxyl groups from diol (b) to the total number of Ri to Re groups from resin (a) is in the range of 1.25 to 2.25.

Melamine aldehyde resins of formula (I) are known in the art and many are commercially available. Examples of suitable commercially available melamine

aldehyde resins include but are not limited to hexamethoxymethyl (HMMM)-type melamine resins such as Cymel® 303 and Cymel® 303LF, available commercially from Cytec Industries Inc., and Resimene® 747 and Resimene® CE7103, available commercially from Surface Specialties. It should be noted that formula (I) represents an ideal structure. Commercial materials often also contain oligomers having more than one triazine ring.

The melamine aldehyde resin is reacted with an α,β-diol or α,γ-diol, or a mixture thereof.

In one embodiment, the α,β-diol or α,γ-diol has from 2 to 18 carbon atoms. In another embodiment it has 2 to 15 carbon atoms. A further embodiment has 2 to 10 carbon atoms. Examples of suitable diols include but are not limited to ethylene glycol, 1 ,2-propane diol, 1 ,3-butane diol, 2-methyl-butane-1 ,3-diol, cyclopentene-1 ,3-diol, 1 ,2-hexane diol, 2-ethyl-1 ,3-hexane diol (EHDO), 2,2,4- thmethyl-1 ,3-pentane diol, 1 ,2-octane diol, 2-butyl-2-ethyl-1 ,3-propane diol (BEPD), 2,4,4-thmethyl-hexane-3,4-diol, 1 ,2-decane diol, 2,3,4,5-tetramethyl- hexane-3,4-diol, and 1 ,2-octadecane diol.

Optionally, a third compound (c) may be used to prepare the novel melamine polyols. These compounds contain at least one functional group capable of reacting with the melamine aldehyde resin (c1 ), or they contain at least one group capable of reacting with the melamine aldehyde resin and other functional groups (c2).

Examples of compounds (c1 ) are mono-alcohols. Examples of the other functional groups from compounds (c2) include carboxyl-functional groups, ethylene oxide-functional groups, ethylenically unsaturated groups, mercapto- functional groups, acetoacetate-functional groups, and mixtures thereof. Also, mixtures of compounds (c1 ) and (c2) can be used.

The melamine polyol suitably contains hydrophilic moieties which support and stabilize dissipation, i.e. emulsification, dispersion or dissolution, of the melamine polyol in an aqueous medium. Examples of suitable hydrophilic moieties are ionic groups, such as carboxylate groups, sulphonate groups, phosphate groups, and ammonium groups. Also non-ionic hydrophilic moieties can be used, such as polyalkylene oxide groups, in particular polyethylene oxide groups, polypropylene oxide groups, and mixtures thereof. The hydrophilic moieties can be introduced into the melamine polyols by selecting compounds (c2) having at least one hydroxyl group and a hydrophilic moiety. Examples of such compounds are 2,2-bis(hydroxyl methyl) propionic acid, a hydroxyl-terminated oligoester having sulphonate groups, and polyethylene glycol monomethyl ether.

Alternatively or additionally, it is also possible to use external emulsifiers for stabilization of the melamine polyol in an aqueous medium. The melamine polyol generally is present in the coating composition in an amount of at least 2% by weight, or at least 5% by weight, or at least 8% by weight, calculated on the non-volatile content of the composition. The amount of melamine polyol in the coating composition generally is at most 30% by weight, or 25% by weight, or 20% by weight, calculated on the non-volatile content of the composition.

In one embodiment, the coating composition according to the invention can applied as a clear coat. In this case, the composition is essentially free of pigments. Alternatively, the composition can comprise pigments and/or colouring agents to provide colour and hiding power. The coating composition according to the invention can further comprise other components and additives conventionally present in coating compositions, such as extenders, pigment dispersants, emulsifiers (surfactants), rheology-controlling agents, levelling agents, flatting agents, coalescents, wetting agents, anti-cratehng agents, anti- foaming agents, biocides, plasticizers, UV absorbers, light stabilizers, and odour masking agents.

In one embodiment the coating composition of the invention also comprises a curing catalyst for the reaction of isocyanate groups and hydroxyl groups. Examples of curing catalysts are metal based curing catalysts and basic catalysts. Suitable metals include zinc, cobalt, manganese, zirconium, bismuth, and tin. It is preferred that the coating composition comprises a tin based catalyst. Well-known examples of tin based catalysts are dimethyl tin dilaurate, dimethyl tin diversatate, dimethyl tin dioleate, dibutyl tin dilaurate, dioctyl tin dilaurate, and tin octoate. As an example of a basic catalyst diazabicyclo[2.2.2]octane may be mentioned.

Also included in the coating composition of the invention may be reactive diluents having a number average molecular weight below 2,000, preferably below 1 ,000, and having isocyanate-reactive functional groups, such as hydroxyl groups. Suitable reactive diluents are water-soluble mono- or polyhydric alcohols. Examples of monohydric alcohols include hexyl glycol, butoxyethanol, 1 -methoxy-2-propanol, 1 -ethoxy-2-propanol, 1-propoxy-2- propanol, 1 -butoxy-2-propanol, 2-methoxybutanol, 1-isobutoxy-2-propanol, dipropylene glycol monomethyl ether, diacetone alcohol, methanol, ethanol, propanol, isopropanol, butanol, 2-butanol, pentanol, hexanol, benzyl alcohol, and mixtures thereof. Examples of polyhydric alcohols include ethylene glycol, diethylene glycol, propylene glycol, isomeric butane diols, the polyethylene oxide glycols or polypropylene oxide glycols, 1 ,1 ,1 -trimethylol propane, 1 ,2,3- trimethylol propane, pentaerythritol, glycerol, and mixtures thereof. Said reactive diluents, if present, are generally used in an amount of 0.1 to 10% by weight, calculated on the non-volatile content of the coating composition.

The coating composition of the invention can further comprise one or more other well-known coating resins, for example, epoxy resins, acrylic resins, for example in the form of acrylic latexes, phenolic resins, cellulose nitrate, polyvinyl butyral resins, etc. If so desired, the other coating resins may be functionalized with hydroxyl-reactive groups selected from the group of isocyanate, epoxy, acetal, carboxyl, anhydride, and alkoxy silane groups. Also, mixtures of these groups in one compound are included. The coating

composition can also comprise an amino resin. Depending on the presence of additional functional groups, the coating composition can further comprise other known curing catalysts, for example, tertiary amines or sulphonic acids, such as p-toluene sulphonic acid and dodecyl benzene sulphonic acid.

The major part of the volatile content of the coating composition of the present invention consists of water. However, the coating composition can contain one or more organic solvents, with the proviso that the volatile organic content (VOC) of the ready-for-use coating composition does not exceed 540 g/l; preferably, it does not exceed 420 g/l. As suitable organic solvents may be mentioned diethylene glycol dimethyl ether, dipropylene glycol dimethyl ether, methyl ether of diacetone alcohol, ethyl acetate, butyl acetate, ethyl glycol acetate, butyl glycol acetate, 1-methoxy-2-propyl acetate, butyl propionate, ethoxy ethyl propionate, toluene, xylene, methylethyl ketone, methyl isobutyl ketone, methyl isoamyl ketone, ethyl amyl ketone, dioxolane, N-methyl-2- pyrrolidone, dimethyl carbonate, propylene carbonate, butyrolactone, caprolactone, and mixtures thereof.

As is usual with coating compositions comprising a hydroxy-functional binder and an isocyanate-functional crosslinker, the composition according to the invention has a limited pot life. In particular, the polyisocyanate has a limited stability in an aqueous environment. Therefore, the composition is suitably provided as a multi-component composition, for example as a two-component composition or as a three-component composition. Therefore, the invention also relates to a kit of parts for preparation of the coating composition comprising a) a water borne binder module comprising at least one polyurethane dispersion and a melamine polyol, and b) a non-aqueous crosslinker module comprising a polyisocyanate. The coating composition of the invention can be prepared by mixing the components of the kit of parts.

The kit of parts suitably comprises metering aids to facilitate mixing of the components in the required ratios. In one embodiment, the modules of the kit of parts comprise the components in the required ratios, i.e. the modules are provided in a plurality of containers which contain the components in the required amounts to form the coating composition of the invention.

Alternatively, the amount of the components can be provided in ratios deviating from the required ratios for the coating composition and additionally a metering aid is provided, such a mixing container having visible indications for the required volumes of the modules to form the coating composition of the invention. The required volumes may also be indicated on a so-called metering stick, which is common in the paint industry. Variations and combinations of suitable metering aids will be readily appreciated by a skilled person.

Application of the coating composition onto a substrate can be via any method known to the skilled person, e.g., via rolling, spraying, brushing, flow coating, dipping, and roller coating. Preferably, a coating composition such as described is applied by spraying. In one embodiment, the water borne binder module and the non-aqueous crosslinker module comprising a polyisocyanate are mixed in a separate container to form the coating composition of the invention, prior to application to a substrate. Alternatively, it is also possible to feed the modules to a two- or plural-component spray gun separately. In this case mixing of the components takes place in the spray gun.

For preparation of a coating, the coating composition of the invention can be applied to any substrate. The substrate may be, for example, metal, e.g., iron, steel, and aluminium, plastic, wood, glass, synthetic polymer, paper, leather, or another coating layer. In particular, the coating compositions of the current invention can be used for the preparation of soft-feel coatings, for example as soft-feel coatings of interior synthetic polymer parts of a motor vehicle, such as instrument panels, door panels, arm rests, head rests, airbag covers, glove compartment covers, and center consoles. In order to obtain sufficient chemical resistance, a dry film layer thickness of more than 40 μm, for example 50 μm or more, is required for conventional soft-feel coatings. At lower dry film layer

thickness the resistance properties of the known coatings are insufficient. With the coating composition according to the invention, it is possible to produce soft feel coatings having sufficient chemical resistance at lower dry film layer thickness, for example 20 to 40 μm, more in particular 25 to 37 μm. The coating compositions are also suitable for coating objects such as bridges, pipelines, industrial plants or buildings, oil and gas installations, or ships.

The applied coating composition can be cured very effectively at a temperature of, e.g., 0-60°C. If so desired, the coating composition may be oven cured, e.g. at a temperature in the range of 60-120°C. Alternatively, curing can be supported by (near) infrared radiation. Before curing at elevated temperature the applied coating composition may optionally be subjected to a flash-off phase.

It is to be understood that the term coating composition as used herein also includes its use as an adhesive composition.

Examples

Raw materials used:

General methods:

The Brookfield viscosity was measured at 25°C, spindle #4, at 20 RPM. The number average and weight average molecular weights were determined by gel permeation chromatography using polystyrene as standard. The film thickness was measured with a Fisher permascope.

The non-volatile content of melamine polyols was determined by measuring the weight loss after heating a sample to 49°C for 90 to 120 minutes.

Synthesis Example 1 Carboxylate-modified water-reducible melamine polyol

A water-reducible melamine polyol was prepared by adding a mixture of 294.8 g of Cymel® 303 and 96.0 g dipropylene glycol dimethyl ether to a mixture of 420.0 g of 2-butyl-2-ethyl-1 ,3-propane diol, 56.3 g of 2,2-bis(hydroxymethyl)- propionic acid, 120.0 g of dipropylene glycol dimethyl ether, 60.0 g of 1 -methyl pyrrolidinone, and 3.6 g of paratoluene sulphonic acid over 2 hours at a temperature of 95°C. Upon feed completion, the reaction temperature was increased to 105 ⁰ C to remove methanol by distillation until a yield of 50%, based on the reaction ethehfied methylol groups, was reached. The resulting resin was then cooled and 15.5 g of thethylamine were added to neutralize the paratoluene sulphonic acid and the carboxylic acid groups.

The resulting melamine polyol had an Mn of 2,510, an Mw of 14,800, and a dispersity of 5.9. The non-volatile content was found to be 70% by weight. The Brookfield viscosity was 1 ,200 cps and the experimental hydroxyl equivalent weight was 224 g/equivalent.

Synthesis Example 2

Sulphonate-modified water-reducible melamine polyol

A water-reducible melamine polyol was prepared first by making a polyester prepolymer by reacting 260.0 g of 2-butyl-2-ethyl-1 ,3-propane diol and 55.0 g of dimethyl 5-sulphoisophthalate sodium salt in the presence of Fascat® 4100. Methanol was removed by distillation until a yield of 70% or greater, based on the reaction of methyl ester groups, was reached. Upon completion of the

reaction, the prepolymer was cooled to 95°C and 140.0 g of dipropylene glycol dimethyl ether and 1.9 g of paratoluene sulphonic acid were added to the prepolymer. A mixture of 140.0 g Cymel 303 and 33.4 g dipropylene glycol dimethyl ether was then added to the prepolymer over 2 hours. Upon feed completion, the reaction temperature was increased to 105 ⁰ C to remove methanol by distillation until a yield of 50%, based on the reaction ethehfied methylol groups, was reached. The resulting resin was then cooled and 2.3 g of N,N-dimethyl ethanolamine were added to neutralize the paratoluene sulphonic acid. The resulting polymer had an Mn of 2,160, an Mw of 21 ,300, and a dispersity of 9.9. The non-volatile content was found to be 70% by weight. The Brookfield viscosity was 4,100 cps and the experimental hydroxyl equivalent weight was 198 g/equivalent.

Coating Composition Example 1

Coating composition 1 according to the invention was prepared as described below. The amounts of the components are given in parts by weight (pbw).

The first three components were premixed in a vessel and the melamine polyol from synthesis Example 1 was added slowly with stirring. Then the following components were added with further stirring:

The following components were sifted in under agitation and mixed for 30 minutes:

The following components were premixed and added to the vessel with stirring:

Subsequently the following was added:

Immediately prior to application, the following components were added:

Coating Composition Example 2

Coating composition 2 according to the invention was prepared as described below. The amounts of the components are given in parts by weight (pbw). The following components were combined with stirring:

The following components were sifted in under agitation and mixed for 30 minutes:

The following components were premixed and added to the vessel with stirring:

Subsequently the following was added:

Immediately prior to application, the following components were added:

Reduced to spray viscosity:

Comparative Coating Composition A

Comparative coating composition A was prepared as described below. The amounts of the components are given in parts by weight (pbw).

The following components were combined with stirring:

The following component was sifted in under agitation and mixed for 30 minutes:

The following components were premixed and added to the vessel with stirring:

Immediately prior to application, the following components were added:

Coating compositions 1 , 2, and A were spray-applied to panels of automotive interior grade plastic. After application, the panels were allowed to flash off at room temperature for 5 minutes. Subsequently, the coated panels were oven cured for 20 minutes at 82°C. The dry film thickness was 25 to 32 μm. The resistance of the coatings to suntan lotion was tested as follows: 1 . A double layer of crock cloth was placed over a test panel, corner to corner.

2. A 0.24 - 0.25 g amount of suntan lotion was placed on top of the crock cloth and spread to a 1 .27 cm diameter circle.

3. A clean 5 cm X 5 cm piece of aluminium was placed on top of the suntan lotion (corner to corner with the crock cloths). 4. The panel with the sunscreen testing equipment was placed in a 74°C oven with a 500 g brass weight placed directly on top of the aluminium.

5. After one hour, the panel was removed from the oven and dismantled in reverse order.

6. After 10 minutes at room temperature, the excess suntan lotion was removed with gentle wiping using a damp cloth.

7. After an additional 5 minutes at room temperature, the panel was tested with the Rockwell five-finger machine at various levels of force (Newtons) until

the failure and pass points were determined. This test determines the degree of film degradation based on dragging a 1 mm round steel tip across the exposed area. The force at which loss of adhesion occurs is recorded. Higher values indicate less degradation of the film.

The visual rating scale is as follows: Visual ratings (appearance)

1 = Pass, no visual effect

2 = Pass, slight colour change, slight cloth impression or blistering

3 = Fail, noticeable colour change, noticeable cloth impression or paint blistered, wrinkled or cracked

4 = Fail, severe colour change, cloth impression or paint blistered, wrinkled or cracked.

The soft-feel properties were determined by the dried coating layers being touched by hand by a plurality of persons. The following levels of properties were distinguished: hard/dry, hard/silky, soft/rubbery, and soft silky. The soft- feel rating shown in the Table below is the average rating given:

The Table below summarizes the results of the suntan lotion resistance tests and the soft-feel properties:

Additionally, the coatings prepared from the composition according to the invention also had very good mar resistance and scratch resistance. From the results it can be inferred that the coatings prepared from the compositions according to the present invention exhibit, at the same layer thickness, a better suntan lotion resistance than the comparative coating prepared from a composition without melamine polyol. Improvement of the suntan lotion

resistance was achieved without deterioration of the soft-feel properties. It is demonstrated that the coatings prepared from the composition according to the invention have an improved balance of chemical and mechanical resistance and soft-feel properties.