WO1997008283A1 - Detergent composition with bleach system stabilized by enzymes - Google Patents

Abstract

The present invention relates to a laundry detergent bar composition comprising: (a) from about 10 % to about 60 % detergent surfactant, wherein anionic surfactant comprises at least about 10 % of the total amount of surfactant; (b) from about 0.10 % to about 60 % bleach agent; and (c) from about 0.0011 mg to about 2.2 mg of active enzyme selected from the group consisting of protease, amylase, cellulase, lipase, peroxidase, and mixtures thereof, per gram of the composition. The addition of enzymes stabilizes the bleach agent and preserves the effectiveness of the bleach in laundry detergent bar compositions.

Description

DETERGENT COMPOSITION WITH BLEACH SYSTEM STABILIZED BY ENZYMES

BACKGROUND OF THE INVENTION

FIELD OF THE INVENTION

This invention relates to a laundry detergent composition. This invention also relates to a laundry detergent bar. More particularly, it relates to a laundry detergent bar containing a bleach system.

DESCRIPTION OF RELATED ART

Detergent compositions in the form of synthetic detergent granules and liquids are used in many societies to launder clothes, particularly in those societies where mechanical washing machines are common.

The prior art generally discloses granular detergent compositions which comprise a bleach system. In addition, the prior art discloses granular detergent compositions comprising a bleach system and enzymes. The following references are hereby incoφorated by reference: Great Britain Publication 1275301, Desforges, published May 24, 1972; Great Britain Publication 2139260, Oakes, published May 2, 1984; U.S. Patent 4,861,509 issued to Cornelissen et al. on August 29, 1989; U.S. Patent 4.769,173 issued to Cornelissen et al. Sept. 6, 1988; European Publication 365,103-A2, Uchiyama et al., published April 25, 1990; European Publication 425214-A2, Donker et al., published May 2, 1991.

In societies where mechanical washing machines are not common, laundry detergent bars comprising synthetic organic surfactants and detergency builders are used in the laundering of clothes. Technical developments in the field of laundry detergent bars have concerned formulating bars which are effective in cleaning clothes; which have acceptable sudsing characteristics in warm and cool water and in hard and soft water; which have acceptable in-use wear rates, hardness, durability, and feel; which have low smear; and which have a pleasing odor and appearance. Methods for making laundry detergent bars are also well known in the art. Prior art disclosing laundry bars and methods for making laundry bars include: U.S. Pat. 3,178,370, Okenfuss, issued April 13, 1995; and Philippine

Pat. 13,778, Anderson, issued September 23, 1980. The prior art generally discloses laundry detergent bars containing a bleach system. In addition, the prior art discloses laundry bars containing sodium perborate monohydrate as a preferred bleach. Such prior art includes Great Britain Publication 2172300, Finch, published September 17, 1986 (equivalent to Philippine Patent 21708).

Without being limited by theory, it is believed that catalase, which is found in body soils found on worn clothes, decomposes perborate and other bleaches in a laundry detergent composition. This problem is unique to bars as compared to granules, where the only time enzymes and bleach interact with catalase is when the granules are dissolved in a dilute washing solution. After a bar is used by t e consumer, the bar is still wet with the wash solution, and the wash solution leaches into the bar's interior - bringing with it the catalase which decomposes the bleach - thereby making the bar's bleach properties less effective for the next use. It is important to preserve the effectiveness of the bleach in bars because the consumer will use the same bar for multiple washes.

It has now been found that enzymes, preferably protease, cellulase or a combination thereof, degrades the catalase, thereby preventing it from decomposing bleach and preserving the effectiveness of the bleach in a laundry detergent bar composition.

SUMMARY OF THE INVENTION

The present invention relates to a laundry detergent bar composition comprising:

(a) from about 10 % to about 60 % detergent surfactant, wherein anionic surfactant comprises at least about 10% ofthe total amount of surfactant; (b) from about 0.10 % to about 60 % bleach agent; and

(c) from about 0.0011 mg to about 2.2 mg of active enzyme selected from the group consisting of protease, amylase, cellulase, lipase, peroxidase, and mixtures thereof, per gram ofthe composition.

A preferred bar composition comprises: (a) from about 1% - 50%, preferably from about l%-20%, of a peroxygen bleach agent, preferably sodium perborate monohydrate (PB1);

(b) from about 0.0055 mg to about 0.022 mg of protease enzyme per gram ofthe composition; and

(c) from about 0.002 mg to about 0.04 mg of cellulase enzyme per gram ofthe composition.

Optionally, the composition further comprises from about 0.1%-5%, preferably from about 0.3%- 1.5%, most preferably at about 0.9% of a phosphonate chelant to stabilize the perborate system. A preferred chelant is diethylene triamine penta (methylene phosphonic acid). A bleach activator can also optionally be included.

All documents referenced herein are incoφorated by reference.

DETAILED DESCRIPTION OF THE INVENTION

While this specification concludes with claims distinctly pointing out and particularly claiming that which is regarded as the invention, it is believed that the invention can be better understood through a careful reading of the following detailed description of the invention. In this specification all percentages are by weight, all temperatures are expressed in degrees Celsius, molecular weights are in weight average, and the decimal is represented by the point (.), unless otherwise indicated.

Detergent Surfactant

The detergent surfactant is preferably at a level from about 10 % to 60 % by weight; more preferably, from about 15 % to about 40 %; and most preferably, from about 20 % to about 35 %.

A preferred surfactant is anionic surfactant, and anionic surfactants comprise at least about 10% ofthe total surfactants in the bar. The anionic surfactant can be selected from:

(a) linear or branched chain alkyl benzene sulfonate having an C8-20 alkyl chain, preferably CIO- 18 alkyl chain, and most preferably a C 12- 16 alkyl chain;

(b) alkyl sulfate having a C8-20 alkyl chain, preferably C14-18 alkyl chain, most preferably C12-16 alkyl chain; (c) alkyl ether sulfate ofthe formula R-En-S03M, wherein:

(i) R is C8-20; and preferably, C 12- 18, alkyl chain;

(ii) E is an ethoxy unit; (iii) n is from 0-20; and

(iv) M is a suitable cation, preferably sodium ion; or alpha-sulfonated fatty acid alkyl ether surfactant of the formula R'-C(S03)H-C(0)-OR", wherein R' is C8-20; most preferably C 18- 18, alkyl chain; and R" is C1-C4 alkyl, preferably methyl; and (d) mixtures thereof.

Mixtures of linear or branched chain alkyl benzene sulfonate and alkyl sulfate can also be used in weight ratios of about 90:10 to 5:95 alkyl benzene sulfonate to alkyl sulfate, preferably from about 30:70 to 0:100. The corresponding mole ratio is about 20:80 to 10:90 alkyl benzene sulfonate to alkyl sulfate, preferably about 18:82 to 12:88, and most preferably about 16:84 to 13:87. Other useful anionic surfactants include water-soluble salts of 2-acyloxy-alkane- 1 -sulfonic acids containing from about 2 to 9 carbon atoms in the acyl group and from about 9 to about 23 carbon atoms in the alkane moiety; water-soluble salts of olefin sulfonates containing from about 12 to 24 carbon atoms; and beta-alkyloxy alkane sulfonates containing from about 1 to 3 carbon atoms in the alkyl group and from about 8 to 20 carbon atoms in the alkane moiety.

Water-soluble salts of the higher fatty acids, i.e., "soaps", also are useful anionic surfactants herein. Soaps can be made by direct saponification of fats and oils or by the neutralization of free fatty acids. Examples of soaps are the sodium, potassium, ammonium, and alkylolamonium salts of higher fatty acids containing from about 8 to about 24 carbon atoms, and preferably from about 12 to about 18 carbon atoms. Particularly useful are the sodium and potassium salts of the mixtures of fatty acids derived from coconut oil and tallow, i.e., sodium or potassium tallow and coconut soaps.

Other anionic surfactants useful herein include:

Sodium alkyl glyceryl ether sulfonates, especially those ethers of higher alcohols derived from tallow and coconut oil;

Sodium coconut oil fatty acid monoglyceride sulfonates and sulfates;

Sodium or potassium salts of alkyl phenol ethylene oxide ether sulfates, and sodium or potassium salts of methyl ester R-CH(Sθ3M)-COOR', wherein R is C8-C22 alkyl or alkenyl, R' is C1-C4 alkyl, and M is a counter ion, preferably Na or K, such as disclosed in WO-93-05013, published March 18, 1992;

Secondary alkyl sulfates having an alkyl chain of from 10 to 20 carbon atoms;

Alkylalkoxy sulfate comprising an alkyl portion of from 6 to 18 carbon atoms and an alkoxy portion comprising, an average, from about 0.5 to about 20 moles of alkoxy, preferably ethoxy, units, more preferably from about 0.5 to about 5 ethoxy units; and

Alkyl ethoxy carboxylates ofthe formula RO(CH₂CH2θ)χCH2COO-M⁺, wherein R is a C₆ to

Cj8 alkyl; x ranges from 0 to 10, and the ethoxylate distribution is such that on a weight basis, the amount of material where x is 0 is less than 20%, the amount of material where x is greater than 7 is less than 25%, and wherein the average x is 2-4 when the average R is C 13 or less, and is 3-6 when the average R is greater than C13; and M is an alkali metal, alkali earth metal, ammonium, mono-, di-, and tri-ethanol ammonium.

Optional detergent surfactants can be included at a level up to about 10%, more preferably from about 1% to about 5% of the total surfactant level in the composition. The types of detergent surfactants that can be used as optional surfactants include cationic, nonionic, amphoteric and zwitterionic surfactants, and mixtures thereof.

Useful optional surfactants can be nonionic, and can include: Alkyl polysaccharides, alkyl polyglucosides, such as described in U.S. Patent 4,565,647,

Llenado;

Polyhydroxy fatty acid amides, of the formula R-C(0)-N(R')-Z, wherein R is C5-C31 hydrocarbyl, preferably Cπ-C 17 alkyl or alkenyl, R' is H, C1-C4 hydrocarbyl, 2-hydroxyethyl, 2-hydroxypropyl, or a mixture thereof, preferably methyl, and Z is polyhydroxy(linear)hydrocarbyl chain having at least 3 hydroxyls directly connected to the chain, preferably -CH2-(CHOH)4-CH2θH, such as described in EP 550,652;

Semi-polar nonionic surfactants, such as water-soluble amine oxide, water-soluble phosphine oxide, and water-soluble sulfoxide surfactants; and

Water-soluble nonionic synthetic surfactants broadly defined as compounds produced by the condensation of ethylene oxide groups (hydrophilic in nature) with an organic hydrophobic compound, which may be aliphatic or alkyl aromatic in nature. The length of the polyoxyethylene group which is condensed with any particular hydrophobic group can be readily adjusted to yield water-soluble compound having the desired degree of balance between hydrophilic and hydrophobic elements.

Cationic surfactants can also be used in the detergent compositions herein and suitable quaternary ammonium surfactants are selected from mono C6-C16, preferably C6-C10 N-alkyl or alkenyl ammonium surfactants wherein remaining N positions are substituted by methyl, hydroxyethyl or hydroxypropyl groups.

Ampholytic surfactants can also be used in the detergent compositions herein, which include aliphatic derivatives of heterocyclic secondary and tertiary amines; zwitterionic surfactants which include derivatives of aliphatic quaternary ammonium, phosphonium and sulfonium compounds; water-soluble salts of esters of alpha-sulfonated fatty acids; betaines having the formula R(R')2N⁺R²COO", wherein R is a C₆-Ci hydrocarbyl group, preferably a Cιo-C]₆ alkyl group or Cιo-Cj6 acylamido alkyl group, each R¹ is typically C1-C3 alkyl, preferably methyl and R2 is a C_\- Cζ hydrocarbyl group, preferably a C1-C3 alkylene group, more preferably a C1-C2 alkylene group. Examples of suitable betaines include coconut acylamidopropyldimethyl betaine; hexadecyl dimethyl betaine; C12-14 acylamidopropylbetaine; C8-14 acylamidohexyldiethyl betaine; 4[Ci4_i6 acylmethylamidodiethylammonio]- 1 -carboxybutane; C 1 (,. _\ % acylamidodimethylbetaine; C12-I6 acylamidopentanediethylbetaine; and

[C12-I6 acylmethylamidodimethylbetaine. Preferred betaines are C 12-18 dimethyl-ammonio hexanoate and the C10-I8 acylamidopropane (or ethane) dimethyl (or diethyl) betaines; and the sultaines having the formula (R(R¹)2N⁺R²S03" wherein R is a Cβ-Cis hydrocarbyl group, preferably a C10-C16 alkyl group, more preferably a C 12-C 13 alkyl group, each R¹ is typically C_\- C3 alkyl, preferably methyl, and R² is a Cj-Cg hydrocarbyl group, preferably a C1-C3 alkylene or, preferably, hydroxyalkylene group. Examples of suitable sultaines include C12-C14 dimethylammonio-2-hydroxypropyI sulfonate, C 12-C 14 amido propyl ammonio-2-hydroxypropyl sultaine, C 12-C 14 dihydroxyethylammonio propane sulfonate, and C j 6- 18 dimethylammonio hexane sulfonate, with C12-14 amido propyl ammonio-2-hydroxypropyl sultaine being preferred.

In addition to the surfactants mentioned above, a hydrotrope, or mixture of hydrotropes, can be present in the laundry detergent bar. Preferred hydrotropes include the alkali metal, preferably sodium, salts of tolune sulfonate, xylene sulfonate, cumene sulfonate, sulfosuccinate, and mixtures thereof. Preferably, the hydrotrope, in either the acid form or the salt form, and being substantially anhydrous, is added to the acid form of the anionic surfactant prior to its neutralization. The hydrotrope will preferably be present at from about 0.5% to about 5% ofthe laundry detergent bar.

Bleach Agent

The bleach agent in the detergent composition is preferably at a level from about 0.10 % to about 60 % by weight; more preferably, from about 1 % to about 50 %; most preferably, from about 1 % to about 20 %. The bleach agents used herein can be any of tiie oxygen bleach agents useful for detergent compositions in textile cleaning, hard surface cleaning, or other cleaning puφoses that are now known or become known. Mixtures of bleach agents can also be used.

The preferred bleach agent for the present invention are those peroxygen bleaching compounds which are capable of yielding hydrogen peroxide in an aqueous solution. These compounds are well known in the art and include hydrogen peroxide and the alkali metal peroxides, organic peroxide bleaching compounds such as urea peroxide, and inorganic persalt bleaching compounds, such as the alkali metal perborates, percarbonates, peφhosphates, and the like. Mixtures of two or more such bleaching compounds can also be used, if desired. Preferred peroxygen bleaching compounds to be used in the present invention include sodium perborate, commercially available in the form of mono- and tetra-hydrates, sodium carbonate peroxyhydrate, sodium pyrophosphate peroxyhydrate, urea peroxyhydrate, and sodium peroxide. Particular preferred are sodium perborate tetrahydrate, and especially, sodium perborate monohydrate. Sodium perborate monohydrate is especially preferred because it is very stable during storage and yet still dissolves very quickly in the bleaching solution.

Persulfate bleach (e.g., OXONE, manufactured commercially by DuPont) can also be used.

A useful percarbonate bleach comprises dry particles having an average particle size in the range from about 500 micrometers to about 1,000 micrometers, not more than about 10% by weight of said particles being smaller than about 200 micrometers and not more than about 10% by weight of said particles being larger than about 1,250 micrometers. Optionally, the percarbonate can be coated with silicate, borate or water-soluble surfactants. Percarbonate is available from various commercial sources such as FMC, Solvay and Tokai Denka.

Another type of useful bleach agent that can be used encompasses percarboxylic acid bleach agents and salts thereof. Suitable examples of this class of agents include magnesium monoperoxyphthalate hexahydrate, the magnesium salt of metachloro perbenzoic acid, 4-nonylamino-4-oxoperoxybutyric acid and diperoxydodecanedioic acid. Such bleach agents are disclosed in U.S. Patent 4,483,781, Hartman, issued November 20, 1984, U.S. Patent Application 740,446, Burns et al, filed June 3, 1985, European Patent Application 0,133,354, Banks et al, published February 20, 1985, and U.S. Patent 4,412,934, Chung et al, issued November 1, 1983. Highly preferred bleach agents also include 6- ηonylamino-6-oxoperoxycaproic acid as described in U.S. Patent 4,634,551, issued January 6, 1987 to Burns et al.

Bleach agents other than oxygen bleach agents are also known in the art and can be utilized herein. One type of non-oxygen bleach agent of particular interest includes photoactivated bleach agents such as the sulfonated zinc and or aluminum phthalocyanines. See U.S. Patent 4,033,718, issued July 5, 1977 to Holcombe et al. If used, detergent compositions will typically contain from about 0.025% to about 1.25%, by weight, of such bleaches, especially sulfonated zinc phthalocyanine.

Enzyme The amount of enzyme in the detergent composition is preferably at a level from about 0.0011 mg to about 2.2 mg of active enzyme per gram of the detergent composition; more preferably, from about 0.0011 mg to about 1.1 mg; and most preferably, from about 0.0011 mg to about 0.55 mg per gram of the composition. Enzymes to be incoφorated include proteases, amylases, lipases, cellulases, and peroxidases, as well as mixtures thereof.

A wide range of enzyme materials and means for their incoφoration into synthetic detergent compositions are also disclosed in U.S. Patent 3,553,139, issued January 5, 1971 to McCarty et al. Enzymes are further disclosed in U.S. Patent 4,101,457, Place et al, issued July 18, 1978, and in U.S. Patent 4,507,219, Hughes, issued March 26, 1985, both. Enzyme materials useful for liquid detergent formulations, and their incoφoration into such formulations, are disclosed in U.S. Patent 4,261,868, Hora et al, issued April 14, 1981. Enzymes for use in detergents can be stabilized by various techniques. Enzyme stabilization techniques are disclosed and exemplified in U.S. Patent 3,600,319, issued August 17, 1971 to Gedge, et al, and European Patent Application Publication No. 0 199 405, Application No. 86200586.5, published October 29, 1986, Venegas. Enzyme stabilization systems are also described, for example, in U.S. Patent 3,519,570.

Suitable examples of proteases are the subtilisins which are obtained from particular strains of B. subtilis 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 Industries A S of Denmark, hereinafter "Novo". The preparation of this enzyme and analogous enzymes is described in GB 1,243,784 to Novo. Other suitable proteases include ALCALASE™ and SAVINASE™ from Novo and MAXATASE™ from International Bio-Synthetics, Inc., The Netherlands; as well as Protease A as disclosed in EP 130,756 A, January 9, 1985 and Protease B as disclosed in EP 303,761 A, April 28, 1987 and EP 130,756 A, January 9, 1985. See also a high pH protease from Bacillus sp. NCIMB 40338 described in WO 9318140 A to Novo. Enzymatic detergents comprising protease, one or more other enzymes, and a reversible protease inhibitor are described in WO 9203529 A to Novo. Other preferred proteases include those of WO 9510591 A to Procter & Gamble . When desired, a protease having decreased adsoφtion and increased hydrolysis is available as described in WO 9507791 to Procter & Gamble. A recombinant trypsin-like protease for detergents suitable herein is described in WO 9425583 to Novo.

In more detail, an especially preferred protease, referred to as "Protease D" is a carbonyl hydrolase variant having an amino acid sequence not found in nature, which is derived from a precursor carbonyl hydrolase by substituting a different amino acid for a plurality of amino acid residues at a position in said carbonyl hydrolase equivalent to position +76, preferably also in combination with one or more amino acid residue positions equivalent to those selected from the group consisting of +99, +101, +103, +104, +107, +123, +27, +105, +109, +126, +128, +135, +156, +166, +195, +197, +204, +206, +210, +216, +217, +218, +222, +260, +265, and/or +274 according to the numbering of Bacillus amyloliquefaciens subtilisin, as described in the patent applications of A. Baeck, et al, entitled "Protease-Containing Cleaning Compositions" having US Serial No. 08/322,676, and C. Ghosh, et al, "Bleaching Compositions Comprising Protease Enzymes" having US Serial No. 08/322,677, both filed October 13, 1994.

Protease enzymes are usually present in an amount that ranges from about 0.0055 mg to about 0.022 mg of active enzyme per gram of the composition. 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.

Cellulase enzymes usable in the present invention include both bacterial or fungal cellulase. Preferably, they will have a pH optimum of between 5 and 9.5. Suitable cellulases are disclosed in U.S. Patent 4,435,307, Barbesgoard et al, issued March 6, 1984, which discloses fungal cellulase produced from Humicola insolens and Humicola strain DSM 1800 or a cellulase 212-producing fungus belonging to the genus Aeromonas, and cellulase extracted from the hepatopancreas of a marine mollusk (Dolabella Auricula Solander). Suitable cellulases are also disclosed in GB-A-2,075,028; GB-A-2,095,275 and DE-OS-2,247,832. CAREZYME™ (Novo) is especially useful.

Cellulase enzymes are usually present in an amount that ranges from about 0.002 mg to about 0.04 mg of active enzyme per gram of the composition. Preferable is Carezyme™ having an activity of 5000 CEVU per gram. Most preferable is Carezyme™ having an activity of 1000 CEVU per gram.

A preferred bar composition comprises a mixture of enzymes:

(1) from about 0.0055 mg to about 0.022 mg of protease enzyme per gram ofthe composition; and

(2) from about 0.002 mg to about 0.04 mg of cellulase enzyme per gram ofthe composition.

Amylases suitable herein, especially for, but not limited to automatic dishwashing puφoses, include, for example, -amylases described in GB 1,296,839 to Novo; RAPID ASE™, Intemationai Bio- Synthetics, Inc. and TERMAMYL™, Novo. FUNGAMYL™ from Novo is especially useful. Engineering of enzymes for improved stability, e.g., oxidative stability, is known. See, for example J. Biological Chem., Vol. 260, No. 11, June 1985, pp. 6518-6521. Certain preferred embodiments ofthe present compositions can make use of amylases having improved stability in detergents such as automatic dishwashing types, especially improved oxidative stability as measured against a reference- point of TERMAMYL™ in commercial use in 1993. These preferred amylases herein share the characteristic of being "stability-enhanced" amylases, characterized, at a minimum, by a measurable improvement in one or more of: oxidative stability, e.g., to hydrogen peroxide / tetraacetylethylenediamine in buffered solution at pH 9-10; thermal stability, e.g., at common wash temperatures such as about 60°C; or alkaline stability, e.g., at a pH from about 8 to about 11, measured versus the above-identified reference-point amylase. Stability can be measured using any of the art-disclosed technical tests. See, for example, references disclosed in WO 9402597. Stability- enhanced amylases can be obtained from Novo or from Genencor International. One class of highly preferred amylases herein have the commonality of being derived using site-directed mutagenesis from one or more of the Bacillus amylases, especially the Bacillus -amylases, regardless of whether one, two or multiple amylase strains are the immediate precursors. Oxidative stability-enhanced amylases vs. the above-identified reference amylase are preferred for use, especially in bleaching, more preferably oxygen bleaching, as distinct from chlorine bleaching, detergent compositions herein. Such preferred amylases include (a) an amylase according to the hereinbefore incoφorated WO 9402597, Novo, Feb. 3, 1994, as further illustrated by a mutant in which substitution is made, using alanine or threonine, preferably threonine, of the methionine residue located in position 197 of the B. licheniformis alpha-amylase, known as TERMAMYL™, or the homologous position variation of a similar parent amylase, such as B. amyloliquefaciens, B. subtilis, or B. stearothermophilus; (b) stability-enhanced amylases as described by Genencor International in a paper entitled "Oxidatively Resistant alpha-Amylases" presented at the 207th American Chemical Society National Meeting, March 13-17 1994, by C. Mitchinson. Therein it was noted that bleaches in automatic dishwashing detergents inactivate alpha-amylases but that improved oxidative stability amylases have been made by Genencor from B licheniformis NCIB8061. Methionine (Met) was identified as the most likely residue to be modified. Met was substituted, one at a time, in positions 8, 15, 197, 256, 304, 366 and 438 leading to specific mutants, particularly important being M197L and M197T with the M197T variant being the most stable expressed variant. Stability was measured in CASCADE™ and SUNLIGHT™; (c) particularly preferred amylases herein include amylase variants having additional modification in the immediate parent as described in WO 9510603 A and are available from the assignee, Novo, as DURAMYL™. Other particularly preferred oxidative stability enhanced amylase include those described in WO 9418314 to Genencor International and WO 9402597 to Novo. Any o.ther oxidative stability-enhanced amylase can be used, for example as derived by site-directed mutagenesis from known chimeric, hybrid or simple mutant parent forms of available amylases. Other preferred enzyme modifications are accessible. See WO 9509909 A to Novo.

Other amylase enzymes include those described in WO 95/26397 and in co-pending application by Novo Nordisk PCT/DK96/00056. Specific amylase enzymes for use in the detergent compositions of the present invention include -amylases characterized by having a specific activity at least 25% higher than the specific activity of Termamyl™ at a temperature range of 25°C to 55°C and at a pH value in the range of 8 to 10, measured by the Phadebas™ -amylase activity assay. (Such Phadebas™ -amylase activity assay is described at pages 9-10, WO 95/26397.) Also included herein are -amylases which are at least 80% homologous with the amino acid sequences shown in the SEQ ID listings in the references. Amylase enzymes are usually present in an amount that ranges from about 0.0045 mg to about 0.45 mg of active enzyme per gram ofthe composition.

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. See also lipases in Japanese Patent Application 53,20487, laid open Feb. 24, 1978. This lipase is available from Amano Pharmaceutical Co. Ltd., Nagoya, Japan, under the trade name 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 Coφ., U.S.A. and Disoynth Co., The Netherlands, and lipases ex Pseudomonas gladioli. LIPOLASE" enzyme derived from Humicola lanuginosa and commercially available from Novo, see also EP 341,947, is a preferred lipase for use herein. Lipase and amylase variants stabilized against peroxidase enzymes are described in WO 9414951 A to Novo. See also WO 9205249 and RD 94359044.

Lipase activity is expressed in Lipase Unit (LU) which is me amount of lipase which produces lμmol of titratable fatty acid per minute in a pH stat. under the following conditions: temperature of 30°C; pH of 9.0; substrate is an emulsion of 3.3 wt% of olive oil and 3.3% gum arabic, in the presence of 13mmol/l Ca2+ mmol/1 NaCl in 5 mmol 1 Tris buffer.

Lipase enzymes are usually present in an amount that ranges from about 0.0022 mg to about 1.1 mg of active enzyme per gram ofthe composition.

Peroxidase enzymes are used in combination with oxygen sources, e.g., percarbonate, perborate, persulfate, hydrogen peroxide, etc. They are used for "solution bleaching," i.e. to prevent the transfer of dyes or pigments removed from substrates during wash operations to other substrates in the wash solution. Peroxidase enzymes are known in the art, and include, for example, horseradish peroxidase, ligninase, and haloperoxidase such as chloro- and bromo-peroxidase. Peroxidase-containing detergent compositions are disclosed, for example, in PCT Intemationai Application WO 89/099813, published October 19, 1989, by O. Kirk, assigned to Novo Industries A S.

Other types of enzymes may also be included. They may be of any suitable origin, such as vegetable, animal, bacterial, fungal and yeast origin. However, their choice is governed by several factors such as pH-activity and or stability optima, thermostability, stability versus active detergents, builders and so on. In this respect bacterial or fungal enzymes are preferred, such as bacterial amylases and proteases, and fungal cellulases. OPTIONAL COMPONENTS

Detergent Builder

The laundry bars of the present invention comprise from about 5% to about 60% by weight detergent builder. Preferred laundry bars comprise from about 5% to about 30 % builder, most preferably from about 5% to about 15%, by weight ofthe bar.

These detergent builders can be, for example, water-soluble alkali-metal salts of phosphates, pyrophosphates, orthophosphates, tripolyphosphates, higher polyphosphates, and mixtures thereof. Builders can also be non-phosphate detergent builders. Specific examples of nonphosphorous, inorganic detergency builders include water-soluble inorganic carbonate and bicarbonate salts. The alkali metal (e.g., sodium and potassium) carbonates, bicarbonates, and silicates are particularly useful herein.

Also useful are aluminosilicate ion exchange materials. These aluminosilicates can be crystalline or amoφhous in stmcture and can be eidier naturally occurring or synthetically derived. Preferred synthetic crystalline aluminosilicate ion exchange materials useful herein are available under the designations Zeolite A and Zeolite X. In an especially preferred embodiment, the crystalline aluminosilicate ion exchange material is Zeolite A and has the formula: Naι₂[(A10₂)i2-(Siθ2)i2]-xH₂O wherein x is from about 20 to about 30, especially about 27.

Water-soluble organic detergency builders, for example alkali metal, ammonium and substituted ammonium polycarboxylates, are also useful herein. Specific examples of useful polycarboxylate builder salts include sodium, potassium, ammonium and substituted ammonium salts of ethylenediaminetetraacetic acid, nitrilotriacetic acid, oxydisuccinic acid, mellitic acid, benzene polycarboxylic acid, polyacrylic acid, polymaleic acid, acrylic acid maleic acid copolymers, polyaspartic acid, and citric acid, or such acids per se. Other useful polycarboxylate detergency builders are the materials set forth in U.S. Pat. 3,308,067 issued to Diehl on March 7, 1967. Mixtures of detergent builders can be used in the present invention.

Bleach activator

The detergent compositions herein may optionally contain one or more bleach activators. If present, the amount of bleach activators will typically be from about 0.05% to about 10%; more typically, from about 0.05% to about 5% by weight. Peroxygen bleach agents, the perborates, the percarbonates, etc., are preferably combined with bleach activators, which lead to the in situ production in aqueous solution (i.e., during the washing process) of the peroxy acid corresponding to the bleach activator. Various nonlimiting examples of activators are disclosed in U.S. Patent 4,915,854, issued April 10, 1990 to Mao et al, and U.S. Patent 4,412,934. The nonanoyloxybenzene sulfonate (NOBS) and tetraacetyl ethylene diamine (TAED) activators are typical, and mixtures thereof can also be used. See also U.S. 4,634,551 for other typical bleaches and activators useful herein.

Highly preferred amido-derived bleach activators are those ofthe formulae: R¹N(R⁵)C(0)R²C(0)L or R¹C(0)N(R⁵)R²C(0)L wherein R' is an alkyl group containing from about 6 to about 12 carbon atoms, R² is an alkylene containing from 1 to about 6 carbon atoms, R^ is H or alkyl, aryl, or alkaryl containing from about 1 to about 10 carbon atoms, and L is any suitable leaving group. A leaving group is any group that is displaced from the bleach activator as a consequence of the nucleophilic attack on the bleach activator by the perhydrolysis anion. A preferred leaving group is phenyl sulfonate.

Preferred examples of bleach activators of the above formulae include (6-octanamido- caproyl)oxybenzenesulfonate, (6-nonanamidocaproyl)oxybenzenesulfonate, (6-decanamido-caproyl)oxybenzenesulfonate, and mixtures thereof as described in U.S. Patent 4,634,551.

Another class of bleach activators comprises the benzoxazin-type activators disclosed by Hodge et al in U.S. Patent 4,966,723, issued October 30, 1990. A highly preferred activator of the benzoxazin- type is:

Still another class of preferred bleach activators includes the acyl lactam activators, especially acyl caprolactams and acyl valerolactams ofthe formulae:

wherein R" is H or an alkyl, aryl, alkoxyaryl, or alkaryl group containing from 1 to about 12 carbon atoms. Highly preferred lactam activators include benzoyl caprolactam, octanoyl caprolactam, 3,5,5- trimethylhexanoyl caprolactam, nonanoyl caprolactam, decanoyl caprolactam, undecenoyl caprolactam, benzoyl valerolactam, octanoyl valerolactam, decanoyl valerolactam, undecenoyl valerolactam, nonanoyl valerolactam, 3,5,5-trimethylhexanoyl valerolactam and mixtures thereof. See also U.S. Patent 4,545,784, issued to Sanderson, October 8, 1985, which discloses acyl caprolactams, including benzoyl caprolactam, adsorbed into sodium perborate.

Bleach catalyst The laundry bar composition of the present invention optionally comprises a bleach catalyst. The catalyst is included in the laundry bar at a level from about 0.002% to about 14%, and preferably from about 0.02% to about 10%.

If desired, the bleach compounds can be catalyzed by means of a manganese compound. Such compounds are well known in the art and include, for example, the manganese-based catalysts disclosed in U.S. Pat. 5,246,621, U.S. Pat. 5,244,594; U.S. Pat. 5,194,416; U.S. Pat. 5,114,606; and

European Pat. App. Pub. Nos. 549,271 Al, 549,272A1, 544,440A2, and 544,490A1; Preferred examples of these catalysts include Mn^2(^u"C)3(1.4,7-trimethyl-l,4,7-triazacyclononane)2(PF6)2,

Mn^πι ₂(u-0) j (u-OAc)2( 1 ,4,7-trimethyl- 1 ,4,7-triazacyclononane)2_(Clθ4)2, Mn^IV (u-0)g( 1 ,4,7- triazacyclononane)4(C10 )4, Mn^mMn^IV ₄(u-0) i (u-OAc)₂.( 1 ,4,7-trimethyl- 1 ,4,7- triazacyclononane)2(Clθ4)3, jMn^(l,4,7-trimethyl-l,4,7-triazacyclononane)-(OCH3)3(PF6), and mixtures thereof. Other metal-based bleach catalysts include those disclosed in U.S. Pat. 4,430,243 and U.S. Pat. 5,114,611. The use of manganese with various complex ligands to enhance bleaching is also reported in the following United States Patents: 4,728,455; 5,284,944; 5,246,612; 5,256,779; 5,280,117; 5,274,147; 5,153,161; and 5,227,084.

As a practical matter, and not by way of limitation, the compositions and processes herein can be adjusted to provide on the order of at least one part per ten million of the active bleach catalyst species in the aqueous washing liquor, and will preferably provide from about 0.1 ppm to about 700 ppm, more preferably from about 1 ppm to about 500 ppm, of the catalyst species in the laundry liquor.

Detergent Chelant

The laundry bar composition ofthe present invention optionally comprises a detergent chelant. The detergent chelant is included in the laundry bar at a level from about 0.1% to about 5.0%, preferably from about 0.3 % to about 1.5%, most preferably 0.9%. Chelants are able to sequester and chelate alkali cations (such as sodium, lithium and potassium), alkali metal earth cations (such as magnesium and calcium), and most preferably, heavy metal cations such as iron, manganese, zinc and aluminum. Preferred cations include sodium, magnesium, zinc, and mixtures thereof. Such detergent chelant component can be used beneficially to improve the surfactant mileage of the present laundry bar, meaning that for a given level of anionic surfactant and level of detergent chelant, equivalent sudsing and cleaning performance can be achieved compared to a similar bar containing a higher level ofthe anionic surfactant but without the detergent chelant.

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 diethylene triamine 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 chelants can be used in a particulate or granular form, or in an aqueous or solvent solution. Methods of preparing such salts and complexes are well known, and are described in U.S. Patent 4,259,200, issued 3/31/81. A preferred form is a particulate or a granular form. Such particulate or granules of the detergent chelant can be formed with an organic or inorganic binding material. A suitable organic binding material is e.g. a nonionic surfactant. Suitable inorganic binding materials include sodium tripolyphosphate, sodium carbonate, magnesium sulfate, and the like. Any granulation technique known in the art can be employed, e.g. by spraying a molten nonionic surfactant on to a moving bed ofthe dried metal complex, fluid-bed drying, etc.

OTHER OPTIONAL COMPONENTS

The detergent bars ofthe present invention can contain up to about 80% by weight of other optional ingredients commonly used in detergent products. The following are representative of such materials, but are not intended to be limiting. Another useful optional component of the laundry detergent bar of this invention is silicate, especially sodium silicate. Sodium silicate can be used at up to about 15% silicate solids having a weight ratio of Si02 to Na2θ between about 1.0: 1 and about 3.4: 1.

Another preferred additional component is layered sodium silicate, most preferably commercially available as SKS-6 (Na2Si2θ5), available from Hoechst, and disclosed in U.S. Patent 4,664,839, issued May 12, 1987. Another preferred layered silicate is disclosed in EP Publication 550,048, July 7, 1993 (Kao), which discloses a synthesized crystalline material having a chain structure and having a composition represented by the following formula in anhydrous form: _xM2θ-_ySiθ2 _ZM'θ, wherein M represents Na and/or K; M' represents Ca and/or Mg; y/x is 0.5 to 2.0; and z x is 0.005 to 1.0, said chain stmcture appearing as a main scattering peak in Raman spectra at least 970+20 cm"¹ in the range of 900 to 1200 cm"¹. Such layered silicate material is particularly preferred because it can provide both alkalinity, and calcium sequestering or builder functionality.

Another preferred additional component of the laundry bar is fatty alcohol having an alkyl chain of 8 to 22 carbon atoms, more preferably from 12 to 18 carbon atoms. Fatty alcohol is effective at reducing the bar wear rate and smear (mushiness) of the present laundry bars. A preferred fatty alcohol has an alkyl chain predominantly containing from 16 to 18 carbon atoms, so-called "high- cut fatty alcohol," which can exhibit less base odor of fatty alcohol relative to broad cut fatty alcohols. Typically fatty alcohol is contained in the laundry bar at up to a level of 10%, more preferably from about 0.75% to about 6%, most preferably from about 2% to about 5%. The fatty alcohol is generally added to the formulation of the present invention as free fatty alcohol. However, low levels of fatty alcohol can be introduced into the bars as impurities or as unreacted starting material. For example, laundry bars based on coconut fatty alkyl sulfate can 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.

The free fatty alcohol can also serve as a suds booster, for reinforcing and extending suds generation and longevity. For suds boosting, a preferred fatty alcohol has an alkyl chain predominantly having 12 to 14 carbon atoms, used in the composition at a level from about 0.5% to 3%. Preferably, a narrow-cut C12 alkyl alcohol is used at a level of 0.5% to 2%.

Known polymeric soil release agents, hereinafter "SRA", can optionally be employed in the present detergent compositions. If utilized, SRA's will generally comprise from about 0.01% to 10.0%, typically from about 0.1% to 5%, preferably from about 0.2% to 3.0% by weight, ofthe compositions. Preferred SRA's typically have hydrophilic segments to hydrophilize the surface of hydrophobic fibers such as polyester and nylon, and hydrophobic segments to deposit upon hydrophobic fibers and remain adhered thereto through completion of washing and rinsing cycles, thereby serving as an anchor for the hydrophilic segments. This can enable stains occurring subsequent to treatment with the SRA to be more easily cleaned in later washing procedures.

SRA's can include a variety of charged, e.g., anionic or even cationic species, see U.S. 4,956,447, issued September 11, 1990 to Gosselink, et al., as well as noncharged monomer units, and their structures may be linear, branched or even star-shaped. They may include capping moieties which are especially effective in controlling molecular weight or altering the physical or surface-active properties. Stmctures and charge distributions may be tailored for application to different fiber or textile types and for varied detergent or detergent additive products.

Preferred SRA's include oligomeric terephthalate esters, typically prepared by processes involving at least one transesterification/oligomerization, often with a metal catalyst such as a titanium(IV) alkoxide. Such esters may be made using additional monomers capable of being incoφorated into the ester stmcture through one, two, three, four or more positions, without, of course, forming a densely crosslinked overall structure.

Suitable SRA's include a sulfonated product of a substantially linear ester oligomer comprised of an oligomeric ester backbone of terephthaloyl and oxyalkyleneoxy repeat units and allyl-derived sulfonated terminal moieties covalently attached to the backbone, for example as described in U.S. 4,968,451, November 6, 1990 to J.J. Scheibel and E.P. Gosselink. Such ester oligomers can be prepared by: (a) ethoxylating allyl alcohol; (b) reacting the product of (a) with dimethyl terephthalate ("DMT") and 1,2-propylene glycol ("PG") in a two-stage transesterification/oligomerization procedure; and (c) reacting the product of (b) with sodium metabisulfite in water. Other SRA's include the nonionic end-capped 1,2-propylene/polyoxyethylene terephthalate polyesters of U.S. 4,711,730, December 8, 1987 to Gosselink et al., for example those produced by transesterification oligomerization of poly(ethyleneglycol) methyl ether, DMT, PG and poly(ethyleneglycol) ("PEG"). Other examples of SRA's include: the partly- and fully- anionic-end- capped oligomeric esters of U.S. 4,721,580, January 26, 1988 to Gosselink, such as oligomers from ethylene glycol ("EG"), PG, DMT and Na-3,6-dioxa-8-hydroxyoctanesulfonate; the nonionic-capped block polyester oligomeric compounds of U.S. 4,702,857, October 27, 1987 to Gosselink, for example produced from DMT, methyl (Me)-capped PEG and EG and/or PG, or a combination of DMT, EG and/or PG, Me-capped PEG and Na-dimethyl-5-sulfoisophthalate; and the anionic, especially sulfoaroyl, end-capped terephthalate esters of U.S. 4,877,896, October 31, 1989 to Maldonado, Gosselink et al., the latter being typical of SRA's useful in both laundry and fabric conditioning products, an example being an ester composition made from m-sulfobeπzoic acid monosodium salt, PG and DMT, optionally but preferably further comprising added PEG, e.g., PEG 3400.

SRA's also include: simple copolymeric blocks of ethylene terephthalate or propylene terephthalate with polyethylene oxide or polypropylene oxide terephthalate, see U.S. 3,959,230 to Hays, May 25, 1976 and U.S. 3,893,929 to Basadur, July 8, 1975; cellulosic derivatives such as the hydroxyether cellulosic polymers available as METHOCEL from Dow; the C1-C4 alkyl celluloses and C4 hydroxyalkyl celluloses, see U.S. 4,000,093, December 28, 1976 to Nicol, et al.; and the methyl cellulose ethers having an average degree of substitution (methyl) per anhydroglucose unit from about 1.6 to about 2.3 and a solution viscosity of from about 80 to about 120 centipoise measured at 20°C as a 2% aqueous solution. Such materials are available as METOLOSE SMI 00 and METOLOSE SM200, which are the trade names of methyl cellulose ethers manufactured by Shinetsu Kagaku Kogyo KK.

Suitable SRA's characterized by poly(vinyl ester) hydrophobe segments include graft copolymers of poly(vinyl ester), e.g., C_]-Cg vinyl esters, preferably poly( vinyl acetate), grafted onto polyalkylene oxide backbones. See European Patent Application 0 219 048, published April 22, 1987 by Kud, et al. Commercially available examples include SOKALAN SRA's such as SOKALAN HP-22, available from BASF, Germany. Other SRA's are polyesters with repeat units containing 10-15% by weight of ethylene terephthalate together with 80-90% by weight of polyoxyethylene terephthalate derived from a polyoxyethylene glycol of average molecular weight 300-5,000. Commercial examples include ZELCON 5126 from Dupont and MILEASE T from ICI.

Another preferred SRA is an oligomer having empirical formula (CAP)2(EG/PG)5(T)5(SIP)ι which comprises terephthaloyl (T), sulfoisophthaloyl (SIP), oxyethyleneoxy and oxy-l,2-propylene (EG/PG) units and which is preferably terminated with end-caps (CAP), preferably modified isethionates, as in an oligomer comprising one sulfoisophthaloyl unit, 5 terephthaloyl units, oxyethyleneoxy and oxy- 1,2-propyleneoxy units in a defined ratio, preferably about 0.5:1 to about 10:1, and two end-cap units derived from sodium 2-(2-hydroxyethoxy)-ethanesulfonate. Said SRA preferably further comprises from 0.5% to 20%, by weight of the oligomer, of a crystallinity-reducing stabiliser, for example an anionic surfactant such as linear sodium dodecylbenzenesulfonate or a member selected from xylene-, cumene-, and toluene- sulfonates or mixtures thereof, these stabilizers or modifiers being introduced into the synthesis vessel, all as taught in U.S. 5,415,807, Gosselink, Pan, Kellett and Hall, issued May 16, 1995. Suitable monomers for the above SRA include Na-2-(2-hydroxyethoxy)-ethanesulfonate, DMT, Na-dimethyl-5-sulfoisophthalate, EG and PG. Yet another group of preferred SRA's are oligomeric esters comprising: (1) a backbone comprising (a) at least one unit selected from the group consisting of dihydroxysulfonates, polyhydroxy sulfonates, a unit which is at least trifunctional whereby ester linkages are formed resulting in a branched oligomer backbone, and combinations thereof; (b) at least one unit which is a terephthaloyl moiety; and (c) at least one unsulfonated unit which is a 1,2-oxyalkyleneoxy moiety; and (2) one or more capping units selected from nonionic capping units, anionic capping units such as alkoxylated, preferably ethoxylated, isethionates, alkoxylated propanesulfonates, alkoxylated propanedisulfonates, alkoxylated phenolsulfonates, sulfoaroyl derivatives and mixtures thereof. Preferred are esters of the empirical formula: {(CAP)x(EG/PG)y'(DEG)y"(PEG)y'"(T)z(SIP)z'(SEG)q(B)m} wherein CAP, EG PG, PEG, T and SIP are as defined hereinabove, (DEG) represents di(oxyethylene)oxy units, (SEG) represents units derived from the sulfoethyl ether of glycerin and related moiety units, (B) represents branching units which are at least trifunctional whereby ester linkages are formed resulting in a branched oligomer backbone, x is from about 1 to about 12, y' is from about 0.5 to about 25, y" is from 0 to about 12, y'" is from 0 to about 10, y'+y"+y'" totals from about 0.5 to about 25, z is from about 1.5 to about 25, z' is from 0 to about 12; z + z' totals from about 1.5 to about 25, q is from about 0.05 to about 12; m is from about 0.01 to about 10, and x, y', y", y"', z, z', q and m represent the average number of moles of the corresponding units per mole of said ester and said ester has a molecular weight ranging from about 500 to about 5,000.

Preferred SEG and CAP monomers for the above esters include Na-2-(2-,3- dihydroxypropoxy)ethanesulfonate ("SEG"), Na-2-{2-(2-hydroxyethoxy) ethoxy} ethanesulfonate ("SE3") and its homologues and mixtures thereof and the products of ethoxylating and sulfonating allyl alcohol. Preferred SRA esters in this class include the product of transesterifying and qligomerizing sodium 2-{2-(2-hydroxyethoxy)ethoxy}ethanesulfonate and or sodium 2-[2-{2-(2- hydroxyethoxy)ethoxy}ethoxy]ethanesulfonate, DMT, sodium 2-(2,3-dihydroxypropoxy) ethane sulfonate, EG, and PG using an appropriate Ti(IV) catalyst and can be designated as (CAP)2(T)5(EG/PG)1.4(SEG)2.5(B)0.13 wherein CAP is (Na+-0₃S[CH₂CH2θ]3.5)- and B is a unit from glycerin and the mole ratio EG/PG is about 1.7:1 as measured by conventional gas chromatography after complete hydrolysis.

Additional classes of SRA's include: (I) nonionic terephthalates using diisocyanate coupling agents to link polymeric ester structures, see U.S. 4,201,824, Violland et al. and U.S. 4,240,918 Lagasse et al.; and (II) SRA's with carboxylate terminal groups made by adding trimellitic anhydride to known SRA's to convert terminal hydroxyl groups to trimellitate esters. With the proper selection of catalyst, the trimellitic anhydride forms linkages to the terminals of the polymer through an ester of the isolated carboxylic acid of trimellitic anhydride rather than by opening of the anhydride linkage. Either nonionic or anionic SRA's may be used as starting materials as long as they have hydroxyl terminal groups which may be esterified. See U.S. 4,525,524 Tung et al.. Other classes include: (III) anionic terephthalate-based SRA's of the urethane-linked variety, see U.S. 4,201,824, Violland et al.; (IV) poly(vinyl caprolactam) and related co-polymers with monomers such as vinyl pyrrolidone and/or dimethylaminoethyl methacrylate, including both nonionic and cationic polymers, see U.S. 4,579,681, Ruppert et al.; (V) graft copolymers, in addition to the SOKALAN types from BASF, made by grafting acrylic monomers onto sulfonated polyesters. These SRA's assertedly have soil release and anti-redeposition activity similar to known cellulose ethers: see EP 279,134 A, 1988, to Rhone- Poulenc Chemie. Still other classes include: (VI) grafts of vinyl monomers such as acrylic acid and vinyl acetate onto proteins such as caseins, see EP 457,205 A to BASF (1991); and (VII) polyester- polyamide SRA's prepared by condensing adipic acid, caprolactam, and polyethylene glycol, especially for treating polyamide fabrics, see Bevan et al., DE 2,335,044 to Unilever N. V., 1974. Other useful SRA's are described in U.S. Patents 4,240,918, 4,787,989 and 4,525,524.

Another preferred optional component in the laundry bar is a dye transfer inhibiting (DTI) ingredient to prevent diminishing of color fidelity and intensity in fabrics. A preferred DTI ingredient can include polymeric DTI materials capable of binding fugitive dyes to prevent them from depositing on the fabrics, and decolorization DTI materials capable of decolorizing the fugitive dye by oxidation. An example of a decolorization DTI is hydrogen peroxide or a source of hydrogen peroxide, such as percarbonate or perborate. Non-limiting examples of polymeric DTI materials include polyvinylpyrridine N-oxide, polyvinylpyrrolidone (PVP), PVP- polyvinylimidazole copolymer, and mixtures thereof.

More specifically, the polyamine N-oxide polymers preferred for use herein contain units having ύje following structural formula: R-A_x-P; wherein P is a polymerizable unit to which an N-O group can be attached or the N-O goup can form part of the polymerizable unit of the N-O group can be attached to both units: A is one ofthe following stmctures; -NC(O)-, -C(0)0-, -S-, -0-, -N=; x is 0 or 1; and R is aliphatic, ethoxylated aliphatic, aromatic, heterocyclic or alicyclic group or any combination thereof to which the nitrogen of the N-O group can be attached or the N-O group is part of these groups. Preferred polyamine N-oxides are those wherein R is a heterocyclic group such as pyrridine, pyrrole, imidazole, pyrrolidine, piperidine and derivatives thereof.

The N-O group can be represented by the following general stmctures:

O O

I I II I

(R_l)x-N-(R₂)y =N-(Rι x (R₃)z

wherein R_\, R2, R3 are aliphatic, aromatic, heterocyclic or alicyclic groups or combinations thereof; x, y and z are 0 or 1 ; and the nitrogen of the N-O group can be attached or form part of any of the aforementioned groups. The amine oxide unit ofthe polyamine N-oxides has a pKa <10, preferably pKa <7, more preferred pKa <6.

Any polymer backbone can be used as long as the amine oxide polymer formed is water-soluble and has dye transfer inhibiting properties. Examples of a suitable polymeric backbone is polyvinyl, polyalkylene, polyester, polyether, polyamide, polyimide, polyacrylate and mixtures thereof. The polymer can include random or block copolymers where one monomer type is an amine N-oxide and the other monomer type is an N-oxide. The amine N-oxide polymers typically have a ratio of amine to the amine N-oxide of 10:1 to 1:1,000,000. However, the number of amine oxide groups present in the polyamine oxide polymer can be varied by appropriate copolymerization or by an appropriate degree of N-oxidation. The polyamine oxides can be obtained in almost any degree of polymerization. Typically, the average molecular weight is within the range of 500 to 1,000,000; more preferred 1,000 to 500,000; most preferred 5,000 to 100,000.

Copolymers of N-vinylpyrrolidone and N-vinylimidazole polymers (referred to as "PVPI") are also preferred for use herein. Preferably the PVPI has an average molecular weight from 5,000 to 1,000,000, more preferably from 5,000 to 200,000, and most preferably from 10,000 to 20,000. (The average molecular weight range is determined by light scattering as described in Barth, et al., Chemical Analysis. Vol 113. "Modem Methods of Polymer Characterization".) The PVPI ςopolymers typically have a molar ratio of N-vinylimidazole to N-vinylpyrrolidone from 1 : 1 to 0.2:1, more preferably from 0.8:1 to 0.3:1, most preferably from 0.6:1 to 0.4:1. These copolymers can be either linear or branched.

The present invention compositions can also optionally contain a polyvinylpyrrolidone ("PVP") having an average molecular weight of from about 5,000 to about 400,000, preferably from about 5,000 to about 200,000, and more preferably from about 5,000 to about 50,000. Examples of PVP are disclosed in, for example, EP-A-262,897 and EP-A-256,696. Compositions containing PVP can also contain polyethylene glycol ("PEG") having an average molecular weight from about 500 to about 100,000, preferably from about 1,000 to about 10,000. Preferably, the weight ratio of PEG to PVP is from about 2: 1 to about 50: 1 , and more preferably from about 3 : 1 to about 10:1. One or more of the polymeric DTI materials can also be combined with one or more of the decolorization DTI materials. The DTI material is advantageously used at levels in the bar up to about 10%, preferably from about 0.05% to 5%, more preferably from about 0.2% to about 2%.

Another preferred optional component in the laundry bar is a fabric softener component. A preferred fabric softener component ingredient can include softening clay, such as montmorillonite, bentonite, and hectorite clay, as well as an acid-treated bentonite or other softening clay. Examples of such clays are disclosed in U.S. Patent 3,959,155, issued May 25, 1976, and U.S. Patent 5,019,292, issued May 28, 1991. The fabric softener component can be added to the bar at a level up to 20%, preferably from about 2% to about 15%.

Sodium sulfate is a well-known filler that is compatible with the compositions of this invention. It can be a by-product of the surfactant sulfation and sulfonation processes, or it can be added separately.

Calcium carbonate (also known as Calcarb) is also a well known and often used component of laundry bars. Such materials are typically used at levels up to 40%, preferably from about 5% to about 25%.

Binding agents for holding the bar together in a cohesive, soluble form can also be used, and include natural and synthetic starches, gums, thickeners, and mixtures thereof. Some binding agents can also serve as soil suspending agents, and can include such as water-soluble salts of carboxymethylcellulose and carboxyhydroxymethylcellulose.

preferred soil suspending agent which can optionally be used is an acrylic/maleic copolymer, commercially available as Sokolan , from BASF Coφ. 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. Dyes, pigments, optical brighteners, germicides, and perfumes can also be added to the bar composition.

PROCESS

The detergent laundry bars of the present invention 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. In a typical process, wherein the surfactant system comprises a mixture of alkylbenzene sulfonate and alkyl sulfate, the raw materials are mixed in the blender. Alkylbenzene sulfonic acid is added into a mixture of alkaline inorganic salts and the resulting partially neutralized mixture is mechanically worked to effect homogeneity and complete neutralization of the mixture. Once the neutralization reaction is completed, the alkyl sulfate surfactant is added, followed by the remaining other ingredient materials. The mixing may take from 1 minute to 1 hour, with the usual mixing time being from 2 to 20 minutes. The blender mix is discharged to a surge tank. The product is conveyed from the surge tank to the mill or refining plodder via a multi-wom transfer conveyor.

After milling or preliminary plodding, the product is then conveyed to a double stage vacuum plodder, operating at a vacuum of, e.g. 600 to 740 millimeters of mercury, so that entrapped air is removed. 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.

EXAMPLES The invention is illustrated by the following non-limiting examples. All parts and percentages herein are by weight unless otherwise stated.

Various bar compositions (Examples A through E) can be made using the method described above.

B

(weight percent) 1

Linear alkyl benzene sulfonate 6.75 6.75 6.75

Alkyl Sulfate 15.75 15.75 15.75

Fatty Alkyl Alcohol 1.00 1.00 1.00

Tetrasodium Pyrophosphate 5.00 5.00 5.00

Sodium Tripolyphosphate 5.00 5.00 5.00

Sodium aluminum silicate 0.975 0.975 0.975

Sodium carbonate 15.00 15.00 15.00

Calcium carbonate 33.15 32.90 33.07

Perborate monohydrate 2.25 2.25 2.25

Carezyme 1000 CEVU/g 0.25 0.25 0.0

Savinase 4T 0.08 0.0 0.08

Diethylenetriamine penta 0.7 0.7 0.7

Fluorescent agents 0.2 0.2 0.2

Acrylate salts 0.4 0.4 0.4

Substituted methyl cellulose 0.72 0.72 0.72

Organic polymers 0.50 0.50 0.50

Ti02 1.00 1.00 1.00

Perfume 0.35 0.35 0.35

Other conventional ingredients Balance Balance Balance

D E

(weight percent)

Linear alkyl benzene sulfonate 6.46 6.46

Soda ash 17.86 17.86

Sodium C12-18 alkyl sulfate 8.96 8.96

C12 free CFA 1.00 1.00

Sodium Tripolyphosphate 10.00 10.00

Zeolite A 1.25 1.25

Sulfuric Acid (98%) 2.50 2.50

Calcium Carbonate 39.10 36.56

Glycerine 1.00 1.00

Fluorescent agents 0.20 0.20

CMC* 0.50 0.50

Acrylic/maleic copolymer 0.455 0.455

Polyvinyl pyridine N-oxide polymer 0.40 0.40

Soil release polymer 0.30 0.30

Ti02 1.00 1.00

Sodium diethylene triamine penta 2.80 2.80

Perfume 0.35 0.35

Savinase 4T 0.08 0.12

Carezyme 1000 CEVU/g 0.25 0.50

Perborate monohydrate 2.25 4.50

Other conventional ingredients Balance Balance

"Substituted cellulosic material

Claims

WHAT IS CLAIMED IS:

1. A laundry detergent bar composition comprising, by weight:

(a) from about 10% to about 60% detergent surfactant, wherein anionic surfactant comprise at least about 10% ofthe total amount of surfactant;

(b) from about 0.10% to about 60% oxygen bleach agent; and (c) from about 0.0011 mg to about 2.2 mg of active enzyme selected from the group consisting of protease, amylase, cellulase, lipase, peroxidase, and mixtures thereof, per gram ofthe composition.

2. The composition according to Claim 1, wherein the oxygen bleach agent is a perborate bleach in an amount from about 1% to about 50%.

3. A composition according to Claim 2, wherein the perborate bleach is sodium perborate monohydrate.

4. A composition according to Claim 2, wherein the enzyme is a mixture of from about 0.0055 mg to about 0.022 mg of protease enzyme per gram ofthe composition and from about 0.002 mg to about 0.04 mg of cellulase enzyme per gram ofthe composition.

5. A composition according to Claim 4, further comprising from about 5% to about 60% detergent builder selected from the group consisting of sodium tripolyphosphate, tetrasodium pyrophosphate, crystalline aluminosilicates, and mixtures thereof.

6. A composition according to Claim 5, further comprising from about 0.1% to about 5.0% phosphonate chelant.

7. A composition according to Claim 6, further comprising from about 0.05 % to about 10% bleach activator selected from the group consisting of nonanolyoxybenzene sulfonate, tetraacetyl ethylene diamine, and mixtures thereof.

8. A laundry detergent bar comprising, by weight:

(a) from about 15% to about 40% anionic surfactant, selected from the group consisting of alkyl sulfate having an alkyl chain of from 10 to 20 carbon atoms, a linear-chain alkylbenzene sulfonate (LAS) having an alkyl chain of from 10 to 22 carbon atoms, a branched-chain alkylbenzene sulfonate (ABS) having an alkyl chain of from 10 to

22 carbon atoms, and mixtures thereof; (b) from about 0.0055 mg to about 0.022 mg of protease enzyme per gram of the composition and from about 0.002 mg to about 0.04 mg of cellulase enzyme per gram ofthe composition; (c) from about 5% to about 30% detergent builder selected from the group consisting of sodium tripolyphosphate, tetrasodium pyrophosphate, crystalline aluminosilicates, and mixtures thereof; and (d) from about 1% to about 20% perborate bleach.

9. A composition according to Claim 8, wherein the perborate bleach is sodium perborate monohydrate.

10. A composition according to Claim 9, further comprising from about 0.3% to about 1.5% phosphonate chelant.