|WO/2012/171859||IMPROVED CORROSION RESISTANCE WHEN USING CHELATING AGENTS IN CHROMIUM-CONTAINING EQUIPMENT|
Trajano, Trace Wendell De Guzman (1630-A, Maceda Street Sampaloc, Manila 1015, PH)
Murkunde, Rohan Govind (12D Ponte Salcedo, Valero Street Salcedo Village, Makati Metro Manila 1227, PH)
Permejo, Fides Laura Rivera (29 Adante Street, Tanong Malabon, Metro Manila 1470, PH)
Villalobos, Maricel Legaspi (34 Kaingin Kawit Cavite 4104, PH)
Trajano, Trace Wendell De Guzman (1630-A, Maceda Street Sampaloc, Manila 1015, PH)
Murkunde, Rohan Govind (12D Ponte Salcedo, Valero Street Salcedo Village, Makati Metro Manila 1227, PH)
Permejo, Fides Laura Rivera (29 Adante Street, Tanong Malabon, Metro Manila 1470, PH)
|1.||A solid shaped laundry detergent composition comprising: A. from about 0.1% to about 50%, preferably from about 0.3% to about 40%, and most preferably from about 0.5% to about 20%, by weight of the composition of gluten ; B. from about 5% to about 60% anionic surfactant; C. from about 1 % to about 60% builder ; and D. the balance adjunct materials.|
|2.||The solid shaped laundry detergent composition according to claim 1, having a specific gravity of from about 1.5 to about 1.8, preferably from about 1.55 to about 1.7, and more preferably from about 1.55 to about 1.65.|
|3.||The solid shaped laundry detergent composition according to claim 1, wherein flour is added to the composition as the source of the gluten.|
|4.||The solid shaped laundry detergent composition according to claim 1, being substantially free of soap, preferably there is less than 0.1% by weight of soap in the composition.|
|5.||The solid shaped laundry detergent composition according to claim 1, further comprising from about 0.001 % to about 5% of an enzyme.|
|6.||A process for making a solid shaped laundry detergent composition comprising: A. mixing an acid precursor of an anionic surfactant, sodium carbonate and gluten to form a premixture; and B. extruding the premixture to form the solid, shaped detergent composition; wherein the process is carried out at a pressure that is equal to or greater than atmospheric pressure.|
|7.||The process according to claim 6, wherein adjunct ingredients selected from the group consisting of neutralized surfactants, phosphates, divalent metal ions, and mixtures thereof are added during the mixing step.|
|8.||The process according to claim 6, wherein adjunct ingredients selected from the group consisting of enzymes, bleaches, bleach activators, addition surfactants, and mixtures thereof are added after the mixing step.|
|9.||The process according to claim 6, wherein flour is added to the composition as the source of the gluten.|
Processes for making the solid, shaped laundry detergent compositions of this invention are also disclosed.
BACKGROUND OF THE INVENTION In many locales, solid shaped laundry detergent compositions such as laundry detergent bars and tablets are used for cleaning clothes. Technical developments in the field of solid shaped laundry detergent compositions have concerned formulating compositions which are effective in cleaning clothes ; which have acceptable sudsing characteristics in warm and cool water, and in hard and soft water; and which have a pleasing odor and appearance.
Processes and machinery for making solid shaped laundry detergent compositions are known.
The size, shape and strength of a solid laundry product are among the many physical characteristics that are important to consumers. Consumers want a bar or tablet that is strong, that is, one that does not crumble or break into small pieces before it is dissolve. But the bar or tablet must be big enough and light enough that the consumer can hold onto it and rub it directly onto fabric articles, as this is the customary use for this type of laundry composition. Thus, the bar or tablet cannot be too compact. Moreover, consumers of solid laundry products are typically looking for a very economical product.
This presents a dilemma for the formulator of such solid laundry products.
The formulator must make a product that cleans effectively, is structural sound, is large enough to be comfortably used by the consumer, and is economical. To produce a structural sound and effective cleaning bar, the formulator need only compress the necessary active ingredients, such as surfactants, builders, bleach, enzymes, etc. Unfortunately, these active ingredients are very expensive, and without any fillers, the solid laundry product will likely be prohibitively expensive.
Thus, fillers are necessary to regulate the size and cost of a solid laundry detergent product.
It is axiomatic that fillers used in solid, shaped laundry detergent compositions should not detrimentally effect cleaning. Nor should the fillers have an adverse effect on the structural characteristics of the solid, shaped laundry product. And the fillers should not degrade any of the aesthetic characteristics of the solid, shaped laundry product, such as the smell color or the feel of the product in the consumer's hand.
Moreover, the formulator of solid, shaped laundry products must consider processing steps in the over all product formulation equation. In the manufacture of solid, shaped laundry products at least one step involves the use of a vacuum to pull off excess air and moisture making the solid, shaped product strong and dry. But using a vacuum in an industrial manufacturing process is an expensive, energy intensive proposition. Thus, to achieve the desired economical product, the formulator must consider ways to reduce processing costs, such as the reduction or elimination of the vacuum drying step.
Accordingly, the need exists for improved filler materials that can be added to solid, shaped laundry detergent products without degrading cleaning efficiency or aesthetics. The need also exists for filler material that improve the quality of the product and make it more economical for consumers. Likewise, there is an ongoing need to find solid, shaped laundry detergent compositions that are easier and more economical to formulate.
SUMMARY OF THE INVENTION The present invention relates to a solid shaped laundry detergent composition comprising from about 0.1% to about 50%, preferably from about 0.3% to about 40%, and most preferably from about 0.5% to about 20%, by weight of the composition of gluten ; from about 5% to about 60% anionic
surfactant; from about 1% to about 60% builder ; and the balance adjunct materials. Preferably, flour is added to the laundry detergent composition as the source of the gluten. Gluten can be separated from flour and added by itself, but this addition step adds cost to the overall manufacturing process.
In another aspect of the present invention, the solid shaped laundry detergent composition has a specific gravity of from about 1.5 to about 1.8, preferably from about 1.55 to about 1.7, and more preferably from about 1.55 to about 1.65. Even more preferably the solid shaped laundry detergent compositions are substantially free of soap, that is, preferably there is less than 0.1% by weight of soap in the composition. And the solid shaped laundry detergent compositions can further comprise from about 0.001% to about 5% of an enzyme.
In yet another aspect of he present invention, there is provided a process for making a solid shaped laundry detergent composition comprising: mixing an acid precursor of an anionic surfactant, sodium carbonate and gluten containing flour to form a pre-mixture; and extruding the pre-mixture to form the solid, shaped detergent composition. These process steps are carried out at a pressure that is equal to or greater than atmospheric pressure. In a preferred embodiment of the processes of this invention, adjunct ingredients selected from the group consisting of neutralized surfactants, phosphates, divalent metal ions, and mixtures thereof are added during the mixing step. In an especially preferred embodiment of the processes of this invention, adjunct ingredients selected from the group consisting of enzymes, bleaches, bleach activators, addition surfactants, and mixtures thereof are added after the mixing step.
It has now been found that the incorporation of gluten, preferably in the form of flour, into a solid, shaped laundry composition can decrease the density of the final product while having no adverse effect on the structural characteristics or the cleaning efficiency. This would not be expected because the specific gravity of flour is relatively high, and one skilled in the art would expect that when this material is added to a solid, shaped laundry detergent composition, the specific gravity would increase, rather than decrease.
Moreover, as an added benefit, it has been found that the gluten reduces, and in some case eliminates the need for a vacuum extrusion step when processing the solid shaped laundry detergent products described herein. The vacuum drying step can be a costly and energy intensive processing step of the manufacturing
process of the products according to this invention. The reduction or elimination of the vacuum drying or extrusion step can result in considerable cost saving to the manufacturer of solid, shaped laundry detergent compositions according to the present invention.
These and other features, aspects, advantages, and variations of the present invention, and the embodiments described herein, will become evident to those skilled in the art from a reading of the present disclosure with the appended claims, and are covered within the scope of these claims.
DETAILED DESCRIPTION OF THE INVENTION All percentages, ratios and proportions herein are by weight of the final composition, unless otherwise specified. All temperatures are in degrees Celsius (°C) unless otherwise specified. All documents cited are incorporated herein by reference in their entireties. Citation of any reference is not an admission regarding any determination as to its availability as prior art to the claimed invention.
Solid Shaped Laundry Detergent Composition The present invention is also directe towards a solid shaped laundry detergent composition comprising gluten. As used herein, the term"shaped" indicates that the solid laundry detergent composition is formed, molded, extruded, or otherwise processed to possess a definite and reproducible exterior appearance. The solid shaped laundry detergent product is preferably a laundry detergent bar, or a laundry detergent tablet, and is suitable for use in manual washing and/or with automatic washing machines. Processes for forming solid shaped laundry detergent compositions are well-known.
Gluten Gluten is a naturally occurring compound that can be found is most flours.
Gluten can be separated from the flour by processes that are well known to those skilled in the food processing industries. Gluten typically comprises between 8% and 15% of the dry weight of wheat flour and is believed to be material in flour that reduces the specific gravity of the overall composition. But to minimize the overall cost of the manufacturing process, gluten can be added to the present compositions in the form of flour. The flour component of this invention may be
either processed or unprocessed flour, and may be either white or whole grain flour. Grains useful for defining the dough of the invention include grain constituents such as flours, germs and bran from wheat, corn, rye protein, triticale, barley, oats, sourgum, rice, millet, and mixtures thereof, in addition to others. The flour constituent of the invention will be present in a concentration ranging from about 1.0% to about 70%, preferably from about 3.0% to about 50%, and most preferably from about 4.0% to about 40%, by weight of the composition.
As stated above, flour has a relatively high specific gravity, and one skilled in the art would expect its addition to increase, rather that decrease the specific gravity of solid, shaped laundry detergents compositions made therewith. But this is not the case. While not wanting to be bound by any one theory, it is believed that the gluten in flour absorbs gas that is generated during the surfactant neutralization process, creating a gas filled particle that reduces the specific gravity of the compositions containing these particles. More specifically, the manufacturing process of the solid, shaped laundry detergent compositions of this invention typically starts by mixing the acid precursor form of an anionic surfactant with a carbonate salt as neutralization agent. During the neutralization reaction gas is generated, typically, the gas is carbon dioxide. When flour is added before, during or shortly after the neutralization step, the evolved gas is believed to be entrained in the gluten of the flour.
Anionic Surfactant The solid shaped laundry detergent composition of the current invention contains, by weight of the solid shaped laundry detergent composition, from about 5% to about 60%, preferably from about 8% to about 40%, and more preferably from about 10% to about 35%, of an anionic surfactant. The anionic surfactant useful herein is well-known, and includes the linear alkyl benzene sulfonates, the branched alkyl benzene sulfonates, the linear-, branched-, and random C10-C20 alkyl sulfates, the C10-C18 secondary (2,3) alkyl sulfates of the formula CH2(CH2)@(CHOSO@-M+) CH2 and CH3 (CH2)@(CHOSO@-M+) CH@CH@ 3'2'x'3'3 3'2'y* 3'23 where x and (y + 1) are integers of at least about 7, preferably at least about 9, and M is a water-solubilizing cation, especially sodium, the unsaturated sulfates such as oleyl sulfate, the C, 0-C, 8 alkyl alkoxy sulfates (especially EO 1-7 ethoxy sulfates), and mixtures thereof. The anionic surfactants useful herein may be
provided in either as a pre-neutralized anionic surfactant and/or in the acid form, and neutralized herein.
Especially valuable herein are linear chain alkylbenzene sulfonates in which the average number of carbon atoms in the alkyl group is from about 11 to 13, abbreviated as C11-13 LAS, and coconut fatty alkyl sulfate in which the average number of carbon atoms in the alkyl group is from about 8 to about 18, abbreviated as C8, 8 CFAS, especially C, 2 CFAS. In a preferred embodiment, the ratio of LAS to CFAS in the solid shaped detergent composition is from about 19: 1 to 1: 9, preferably from about 10: 1 to about 1: 5, and more preferably from about 4: 1 to about 1: 3, by weight, in the final composition.
Typically, the anionic surfactant will further comprise a tallow alkyl sulfate.
In such cases, the anionic surfactant contains therein a mixture of fatty acids of tallow and coconut oil having a weight ratio of tallow : coconut fatty acid of from about 85: 15 to about 50: 50, preferably from about 80: 20 to about 65: 35.
Builder The solid shaped laundry detergent composition of the present invention contains, by weight of the solid shaped laundry detergent composition, from about 1% to about 60%, preferably from about 5% to about 50%, and more preferably from about 10% to about 30% builder. The builder useful herein includes the phosphates, pyrophosphates, orthophosphates, tripolyphosphates, higher polyphosphates, and mixtures thereof. The water soluble alkali metal salts of these builders are preferred. A preferred builder is a phosphate builder such as a water-soluble alkali metal salts of tripolyphosphates, and a mixture of tripolyphosphates and pyrophosphates. Specific preferred examples of a builder useful herein include the sodium tripolyphosphates (STPP), tetra sodium pyrophosphates (TSPP), and mixtures thereof.
The laundry detergent composition of the present invention may optionally contain in addition to phosphate builders, non-phosphate builders. Specific examples of a non-phosphate builder, such as inorganic detergency builders, include the water soluble inorganic carbonate and bicarbonate salts. The alkali metal (e. g., sodium and potassium) carbonates and bicarbonates are particularly useful herein. Other specifically preferred examples of a builder useful herein include polycarboxylates.
Co-polymers of acrylic acid and maleic acid are preferred in the subject compositions as auxiliary builders, since it has been observed that their use in combination with fabric softening clay and clay flocculating agents further stabilizes and improves the clay deposition and fabric softening performance.
Adjunct Materials The balance of the solid shaped laundry detergent composition disclosed herein is made up of adjunct materials, some non-limiting examples of which are listed below. Unless otherwise noted, all of the percentages below are by weight of the solid shaped laundry detergent composition.
A highly preferred optional component herein is an enzyme. The enzyme useful herein has an enzymatic activity, and includes an amylase, a cellulase, a cutinase, a lipase, a peroxidase, a protease, and mixtures thereof. Preferred selections are influenced by factors such as pH-activity and/or stability optima, thermostability, and stability to active detergents, builders and the like. In this respect bacterial or fungal enzymes are preferred, such as bacterial amylases and proteases, and fungal cellulases. An enzyme is typically incorporated into a laundry detergent composition at levels sufficient to provide a"cleaning-effective amount."The term"cleaning effective amount"refers to any amount capable of producing a cleaning, stain removal, soil removal, whitening, deodorizing, or freshness-improving effect on substrates such as fabrics, and the like. In practical terms for current commercial preparations, typical amounts are up to about 5 mg by weight, more typically 0.01 mg to 3 mg, of active enzyme per gram of the detergent composition. Stated otherwise, the compositions herein will typically comprise from about 0.001% to about 5%, preferably about 0.01% to about 1% by weight of a commercial enzyme preparation. Protease enzymes are usually present in such commercial preparations at levels sufficient to provide from 0.005 to 0.1 Anson units (AU) of activity per gram of composition. Higher active levels may also be desirable in highly concentrated detergent formulations.
Amylases are particularly suitable for automatic dishwashing purposes.
An amylase useful herein includes, for example,-amylases described in GB 1,296,839 to Outtrup H, et al., published November 22,1972 to Novo Industries A/S of Denmark (hereinafter,"Novo"); RAPIDASED from International Bio- Synthetics, Inc. ; TERMAMYL from Novo; FUNGAMYL from Novo; and DURAMYLO from Novo.
Cellulases usable herein include both bacterial and fungal types, preferably having a pH optimum between 5 and 9.5. U. S. Patent No. 4,435,307, to Barbesgoard, et al., March 6,1984, discloses suitable fungal cellulases from Humicola insolens or Humicola strain DSM1800 or a cellulase 212-producing fungus belonging to the genus Aeromonas, and cellulase extracted from the hepatopancreas of a marine mollusk, Dotabella Auricula Solander. Suitable cellulases are also disclosed in GB-B-2,075,028 to Barbesgaar, et al., issued March 28,1984; GB-B-2,095,275 to Murata, et al., issued August 7,1985 and DE-OS-2,247,832 to Horikoshi and Ikeda, issued June 27 1974. CAREZYME and CELLUZYMEO (Novo) are especially useful. See also WO 91/17243 to Hagen, et al., published November 14,1991.
Cutinase enzymes suitable for use herein are described in WO 8809367A to Kolattukudy, et al., published December 1,1988.
Suitable lipase enzymes for detergent usage include those produced by microorganisms of the Pseudomonas group, such as Pseudomonas stutzeri ATCC 19.154, as disclosed in GB 1,372,034 to Dijk and Berg, published October 30,1974. See also lipases in Japanese Patent Application 53,20487 to Inugai, published February 24,1978. This lipase is available from Amano Pharmaceutical Co., Ltd., Nagoya, Japan, under the tradename LIPASE P "AMANO,"or"AMANO-P."Other suitable commercial lipases include Amano- CES, lipases ex Chromobacter viscosum, e. g. Chromobacter viscosum var. lipolyticum NRRLB 3673 from Toyo Jozo Co., Tagata, Japan; Chromobacter viscosum lipases from U. S. Biochemical Corp., U. S. A. and Disoynth Co., the Netherlands, and lipases ex Pseudomonas gladioli. LIPOLASEO enzyme derived from Humicola lanuginosa and commercially available from Novo, see also EP 341,947 to Cornelissen, et al., issued August 31,1994, also describes a preferred lipase for use herein. Lipase and amylase variants stabilized against peroxidase enzymes are described in WO 94/14951 to Halkier, et al., published July 7,1994 A to Novo. See also WO 92/05249 to Clausen, et al., published April 2,1992.
Peroxidase enzymes may be used in combination with oxygen sources, e. g., percarbonate, perborate, hydrogen peroxide, etc., for"solution bleaching"or prevention of transfer of dyes or pigments removed from substrates during the wash to other substrates present in the wash solution. Known peroxidases include horseradish peroxidase, ligninase, and haloperoxidases such as chloro-
or bromo-peroxidase. Peroxidase-containing detergent compositions are disclosed in WO 89/09813 A to Damhus, et al., published October 19,1989.
A suitable example of a protease is a subtilisin, which is obtained from particular strains of B. subtils and B. licheniformis. One suitable protease is obtained from a strain of Bacillus, having maximum activity throughout the pH range of 8-12, developed and sold as ESPERASE by Novo. Other examples of a suitable protease includes ALCALASE and SAVINASE (D from Novo and MAXATASE from International Bio-Synthetics, Inc., the Netherlands ; as well as Protease A and Protease B as disclosed in EP 130,756 A to Bott, published January 9,1985. An especially preferred protease, referred to as"Protease D," as described in U. S. Patent No. 5,679,630 to A. Baeck, et al, issued October 21, 1997, entitled"Protease-Containing Cleaning Compositions,"and U. S. Patent No. 5,677,272 to C. Ghosh, et al, issued October 14,1997, entitled"Bleaching Compositions Comprising Protease Enzymes." Moisture is typically present at from about 0.5% to about 30%, preferably from about 1 % to about 10%, more preferably from about 2% to about 6%.
A preferred adjunct material in the laundry detergent composition is a dye transfer inhibitor ("DTI") ingredient to reduce or prevent diminishing of color fidelity and intensity in fabrics, and the transfer of dyes. A preferred DTI ingredient includes a traditional polymeric dye transfer inhibition material capable of binding fugitive dyes to prevent them from depositing on the fabrics, a decolorization dye transfer inhibition material capable of decolorizing the fugitives dye by oxidation, or a combination thereof. Non-limiting, preferred examples of an DTI ingredient includes polyvinylpyrridine N-oxide (PVNO), polyvinylpyrrolidone (PVP), polyvinylimidazole, N-vinylpyrrolidone and N- vinylimidazole copolymers (referred to as"PVPI"), copolymers thereof, and mixtures thereof. A highly preferred DTI ingredient useful herein is a modified polyethyleneimine polymer, such as described in U. S. Patent No. 4,548,744 to Connor, issued October 22,1985; U. S. Patent No. 4,597,898 to Vander Meer, issued July 1,1986; and U. S. Patent No. 5,565,145 to Watson, et al., issued October 15, 1996.
An example of an DTI ingredient which provides dye transfer inhibition effects via decolorization is hydrogen peroxide or a hydrogen peroxide source, such as percarbonate or perborate. The amount of DTI ingredient included in
the subject compositions, if any, is less than about 5%, preferably from about 0.05% to about 3%, more preferably from about 0.1 % to about 2%.
Soil suspending agents may also be used herein. One such soil suspending agent is an acrylic/maleic copolymer, commercially available as Sokolan, from BASF Corp. Other soil suspending agents include polyethylene glycols having a molecular weight of about 400 to 10,000, and ethoxylated mono-and polyamines, and quaternary salts thereof. A highly preferred soil suspending agent is a water-soluble salt of carboxymethylcellulose and carboxyhydroxymethylcellulose. Soil suspending agents may be used at levels up to about 5%, preferably about 0.1 % to about 1 %.
The solid shaped laundry detergent composition of the present invention may contain an optional surfactant commonly used in detergent products, such as a cationic surfactant, a nonionic surfactant, an amphoteric surfactant, a zwitterionic surfactant, and mixtures thereof. A typical listing of the classes and species of optional surfactants, and other ingredients useful herein appears in U. S. Patent No. 3,664,961 to issued to Norris on May 23, 1972, and EP 550,652, published on April 16,1992. Such optional surfactants, if present, can be included at levels up to a total of about 10%, preferably from about 0.5% to about 5%. It is preferred that a nonionic surfactant be included herein.
The solid shaped laundry detergent composition may optionally contain a fabric softening clay, preferably a smectite-type clay. The smectite-type clays can be described as expandable, three-layer clays ; i. e., alumino-silicates and magnesium silicates, having an ion exchange capacity of at least about 50 meq/100 g of clay. Preferably the clay particles are of a size that they can not be perceived tactilely, so as not to have a gritty feel on the treated fabric of the clothes. The fabric softening clay may be added at levels of from about 1 % to about 50%, preferably from about 2% to about 20%, and more preferably about 3% to 14%.
Another preferred optional component herein is a secondary fabric softener component in addition to the fabric softening clay. Such materials may be present at levels of about 0.1% to 5%, more preferably from 0.3% to 3%, and include : amines of the formula R4R5R6N, wherein R4 is C5 to C22 hydrocarbyl, R5 and R6 are independently Cl to C10 hydrocarbyl. One preferred amine is ditallowmethyl amine; complexes of such amines with fatty acid of the formula R7COOH, wherein R7 is Cg to C22 hydrocarbyl, as disclosed in EP Pub. No. 0
133 804; complexes of such amines with phosphate esters of the formula RgO- P (O) (OH)-ORg and HO-P (O) (OH)-ORg, wherein R8 and Rg are independently Cl to C20 alkyl of alkyl ethoxylate of the formula-alkyl- (OCH2CH2) ; cyclic amines such as imidazolines of the general formula 1- (higher alkyl) amido (lower alkyl)-2- (higher alkyl) imidazoline, where higher alkyl is from 12 to 22 carbons and lower alkyl is from 1 to 4 carbons, such as described in UK Patent Application GB 2,173,827; and quaternary ammonium compounds of the formula R10R11R12R13N+X-, wherein R10 is alkyl having 8 to 20 carbons, Rn is alkyl having 1 to 10 carbons, R12 and R13 are alkyl having 1 to 4 carbons, preferably methyl, and X is an anion, preferably Cl-or Br, such as C12-13 alkyl trimethyl ammonium chloride.
It has been found that the use of a clay flocculating agent in conjunction with a softening clay provides surprisingly improved softening clay deposition onto the clothes and clothes softening performance, compared to that a formula comprising softening clay alone. The polymeric clay flocculating agent provides improved deposition of the fabric softening clay, and typically, have a molecular weight greater than about 100,000. Examples of such materials include long chain polymers and copolymers derived from monomers such as ethylene oxide, acrylamide, acrylic acid, dimethylamino ethyl methacrylate, vinyl alcohol, vinyl pyrrolidone, and ethylene imine. Gums, like guar gums, are suitable as well.
The preferred clay flocculating agent is a poly (ethylene oxide) polymer. The amount of clay flocculating agent, if any, is typically from about 0.2 to about 2%, preferably from about 0.5 to about 1 %.
A particularly preferred adjunct material herein is a detergent celant.
Such chelants sequester and chelate alkali cations (such as sodium, lithium and potassium), alkali metal earth cations (such as magnesium and calcium), and most importantly, heavy metal cations such as iron, manganese, zinc and aluminum. Preferred cations include sodium, magnesium, zinc, and mixtures thereof. The detergent chelant is particularly beneficial for maintaining good cleaning performance and improved surfactant mileage, despite the presence of the softening clay and the clay flocculating agent.
The detergent chelant is preferably a phosphonate chelant, particularly one selected from the group consisting of diethylenetriamine penta (methylene phosphonic acid), ethylene diamine tetra (methylene phosphonic acid), and mixtures and salts and complexes thereof, and an acetate chelant, particularly
one selected from the group consisting of diethylenetriamine penta (acetic acid), ethylene diamine tetra (acetic acid), and mixtures and salts and complexes thereof. Particularly preferred are sodium, zinc, magnesium, and aluminum salts and complexes of diethylenetriamine penta (methylene phosphonate) diethylenetriamine penta (acetate), and mixtures thereof. Preferably such salts or complexes have a molar ratio of metal ion to chelant molecule of at least 1: 1, preferably at least 2 : 1.
The detergent chelant may be included herein at a level up to about 5%, preferably from about 0.1% to about 3%, more preferably from about 0.2% to about 2%, even more preferably from about 0.5% to about 1 %.
Another preferred addition component of the laundry detergent composition is fatty alcohol having an alkyl chain of 8 to 22 carbon atoms, more preferably from 12 to 18 carbon atoms. Typically, the fatty alcohol is present at up to a level of 10%, more preferably from about 0.75% to about 6%, and even more preferably from about 2% to about 5%. The fatty alcohol is generally added to a solid shaped detergent composition as free fatty alcool. However, low levels of fatty alcohol may be introduced as impurities or as unreacted starting material. For example, solid shaped laundry detergent compositions based on coconut fatty alkyl sulfate may contain, as unreacted starting material, from 0.1 % to 3.5%, more typically from 2% to 3%, by weight of free coconut fatty alcohol on a coconut fatty alkyl sulfate basis.
A highly preferred adjunct material herein is a bleach component. The bleaching component may be a source of-OOH group, such as sodium perborate monohydrate, sodium perborate tetrahydrate and sodium percarbonate. Sodium percarbonate (2Na2CO3 3H202) is preferred since it has a dual function of both a source of HOOH and a source of sodium carbonate.
Another optional bleaching component is a peracid per se, such as represented by the formula : CH3 (CH2) w-NH-C (O)- (CH2) zC03H wherein z is from 2 to 4 and w is from 4 to 10. The bleaching component can contain, as a bleaching component stabilizer, a chelating agent of polyaminocarboxylic acids, polyaminocarboxylates such as ethylenediaminotetraacetic acid, diethylenetriaminopentaacetic acid, and ethylenediaminodisuccinic acid, and their salts with water-soluble alkali metals.
The bleach components, if any, may be added at a level up to about 20%, preferably from about 1% to about 10%, and more preferably from about 2% to about 6%.
Nonlimiting examples of additional bleach activators useful herein are found in U. S. Patent No. 4,915,854 to Baker, et al., issued April 10,1990; U. S.
Patent No. 4,412,934 to Chung and Spadini, issued November 1,1983; and U. S.
Patent No. 4,634,551 to Hardy and Ingram, issued January 6,1987. The hydrophobic activator nonanoyloxybenzene sulfonate (NOBS) and the hydrophilic tetraacetyl ethylene diamine (TAED) activator are typical, and mixtures thereof can also be used.
Another adjunct material is a photobleach material, particularly the phthalocyanine photobleaches which are described in U. S. Patent No. 4,033,718 issued July 5,1977. Preferred photobleaches are metal phthalocyanine compounds, the metal preferably having a valance of +2 or +3; zinc and aluminum are preferred metals. Such photobleaches are available, for example, as zinc phthalocyanine sulfonate. The photobleach components, if included, are typically at levels up to about 0.02%, preferably from about 0.001% to about 0.015%, and more preferably from about 0.002% to about 0.01 %.
The solid shaped laundry detergent compositions may also contain a filler therein. Fillers include minerals, such as talc, bentonite, and hydrated magnesium silicate-containing minerals, where the silicate is mixed with other minerals, e. g., old mother rocks such as dolomite. Sodium sulfate is a well- known filler useful herein. It may be a by-product of the surfactant sulfation and sulfonation processes, or it can be added separately. Calcium carbonate is also a well known and often used filler component, especially in a laundry detergent bar. Filler materials are typically used, if included, at levels up to 40%, preferably from about 5% to about 25%.
Binding agents are especially useful in a solid shaped laundry detergent composition, for holding it together in a cohesive, yet soluble form. Binding agents include natural and synthetic starches, gums, thickeners, and mixtures thereof. An example of a preferred binding agent is coconut monoethylene amide, and related materials. Such materials, if included, are typically at levels up to about 3%, and preferably from about 0.5 to about 2%.
Glycerine is commonly incorporated in a laundry detergent bar composition at concentrations up to about 3%, preferably about 0.5-1.5%.
Process For Making The preferred process of the present invention is described below. The detergent bars can be processed in conventional soap or detergent bar making equipment with some or all of the following key equipment: blender/mixer, mill or refining plodder, two-stage vacuum plodder, logo printer/cutter, cooling tunnel and wrapper. But as discussed above, it is preferred to find a process that eliminates the need for the vacuum plodder.
In a preferred process, the raw materials are mixed in the blender. An acid surfactant, such as alkyl benzene sulfonic acid, is reacted with alkaline inorganic salts to complete neutralization, the amount of alkaline inorganic salt being at least sufficient to completely neutralize the acid. Phosphates, divalent metal ions, addition surfactants and other conventional detergent ingredients can be added during this step. In an alternate process, neutralized surfactant is added in the blender. The gluten, preferably in the form of flour, is added along with the other raw ingredients, although it can be added shortly before the acid neutralization step, or shortly after this step. The gluten/flour addition, however, should be generally contemporaneous with this acid neutralization step.
Other optional components are then added to the mixture. The mixing can take from one minute to one hour, with the usual mixing time being from about two to twenty minutes. The blender mix is charged to a surge tank. The product is conveyed from the surge tank to the mill or refining plodder via a multiworm conveyor.
After milling or preliminary plodding, the product is then conveyed to a two-stage vacuum plodder, operating at high vacuum, e. g. 600 to 740 mm of mercury vacuum, so that entrapped air/gas is removed. But in a highly preferred embodiment of this invention the vacuum plodder is eliminated and the solid, shaped laundry detergent composition is extruded after the milling or preliminary plodding step. The product is extruded and cut to the desired bar length, and printed with the product brand name. The printed bar can be cooled, for example in a cooling tunnel, before it is wrapped, cased, and sent to storage.
Another preferred laundry bar composition is made by the following method: The raw materials are first mixed in a blender. Sodium carbonate and pre-neutralized CFAS is mixed for about 1-2 minutes, in order to make a mixed anionic LAS/Alkyl Sulfate surfactant bar composition. This is followed by the
addition of linear alkyl benzene sulfonic acid and sulfuric acid (if present in the formulation). The acids are then completely neutralized by the sodium carbonate in the seat of the blender. Gluten or flour can be added at any point in this process, but is preferably added contemporaneously with the acid neutralization step. (The amount of sodium carbonate should be at least an amount sufficient to neutralize the acids.) Sodium tripolyphosphate is added before the acids are completely neutralized. The materials are mixed for an addition 1-2 minutes after dosing. Once the neutralization reaction is completed, a chelant, if present is added, followed by calcium oxide or calcium hydroxide and other optional surfactants, and any other additional optional components. The mixing can take from one minute to one hour, with the usual mixing time being from about five to ten minutes. As one of the last ingredients, bleach and enzymes are added to the mixture and then mixed for an addition one to five minutes. The blender mix is charged to a surge tank. The product is conveyed from the surge tank to the mill or refining plodder via a multi-worm conveyor.
After milling or preliminary plodding, the product is preferably extruded, but it can alternatively be conveyed to a two-stage vacuum plodder, operating at high vacuum, e. g. 600 to 740 mm of mercury vacuum, so that entrapped air is removed. As discussed above, however, one of the benefits of the present invention is the potential of eliminating the vacuum extruder step altogether. As an alternative to extrusion, the bars can be stamped by conventional stamping equipment. After the product is extruded or stamped and cut to the desired bar length, it can then be printed with the product brand name. The printed bar can be cooled, for example in a cooling tunnel, before it is wrapped, cased, and sent to storage.
EXAMPLE I Examples of the invention are set forth hereinafter by way of illustration and are not intended to be in any way limiting of the invention. Solid shaped detergent compositions are formed according to the following formulations: TABLE I Comparitive A B C Sodium CFAS 14. 5 13 13. 5 14. 5 Sodium LAS 6.15 7 6.5 6. 15 STPP 11. 6 18 18 11. 6 Gluten 0 1. 0 2. 5. 0 Sodium 12 12 15 12 carbonate SAVINASEO * 0. 08 0. 08 0. 08 0. 08 CAREZYMEO** 0. 08 0. 08 0. 08 0. 08 Perfume 0. 5 0. 4 0. 6 0. 5 Adjunct balance balance balance balance materials Specific Gravity1. 81. 71. 61. 55 * Protease available from Novo.
** Cellulase available from Novo.