CN101550385B - Laundry soap bars with improved storage stability - Google Patents

Abstract

The present invention relates to a process for the preparation of laundry soap bars comprising the steps of a) Preparing a premix by mixing an enzyme, a stabilizer, a polyol and optionally a pH controlling agent; b) Mixing the premix of step a) with a soap,- c) Refining the mixture of b) to refined soap; and d) Plodding the refined soap of step c).

Description

Laundry soap bars with improved storage stability

field of invention

The present invention relates to a laundry bar with improved enzyme stability, a process for the preparation of the laundry bar and the use of the laundry bar. the

Background of the invention

Adding enzymes to laundry bars is well known. When adding enzymes to laundry bars, the stability of the added enzymes during production and storage becomes very important. Of course it is desirable to keep as much activity as possible. the

The activity of added enzymes can be affected eg by the water content of the laundry bar. High levels of water generally lead to lower activity of added enzymes in storage, especially for proteases. the

GB2186883 describes laundry bars with a water content of 10-33% and containing proteases, wherein the proteolytic enzymes are stabilized by a mixture of boron compounds, polyols, organic acids or their alkali metal salts and non-boron compounds Alkali metal salts of inorganic acids. the

WO98/54285 describes high moisture protease containing laundry bars with improved protease stability. This improved stability is obtained by adding stabilizers made from borates together with polyols, carboxylates, carboxylic acids or mixtures thereof. the

In WO 97/36958 the enzyme stability of cellulase is improved by providing a laundry bar containing from about 0.5% to about 60% of a syndet surfactant, with about 4% in the final laundry bar composition. % or less moisture, and from about 0.1% to about 10% of non-liquid thixotropic binding agents, and cellulase. the

The prior art cited above all deals with enzyme stability during storage and use, however when enzymes are incorporated into laundry detergent bar compositions loss of enzyme activity during manufacture of the laundry bar is also an important issue. This loss of enzyme stability is believed to be due to denaturation of the enzyme due to exposure of the enzyme to high shear and high pH and/or high temperature. High temperatures are often necessary in order to process laundry bar components containing synthetic surfactants and having relatively high moisture levels to have acceptable physical properties. If the enzyme is added in the form of granules or pellets, the high shear action on the laundry bar composition in the mill and/or molding machine will destroy the integrity of the enzyme granules and enzyme pellets, and The enzyme is exposed to attack by hostile compounds, such as anionic surfactants. the

WO98/18897 describes a method of incorporating enzymes into laundry detergent bar compositions which minimizes loss of enzyme stability during the manufacture of the laundry bar. This is achieved by adding enzyme pellets to the mixture after milling and cooling and then plodding. the

Summary of the invention

It is an object of the present invention to provide a liquid enzyme-containing premix for use in the preparation of laundry bars. Another object of the present invention is to provide a soap bar comprising enzymes and providing acceptable enzyme stability. Another object of the present invention is to provide a process for the preparation of enzyme-containing laundry bars with improved storage stability. Another object of the present invention is to provide a laundry bar prepared by the method of the present invention. the

The present inventors have surprisingly found that during the manufacture of laundry soap bars, preparation of a premix comprising liquid enzyme product, stabilizer and polyol, rather than adding each component separately to the bar, significantly improves the quality of the laundry soap bar. Storage stability of enzymes in strips. the

Accordingly, another aspect of the present invention is to provide a premix comprising an enzyme, a stabilizer and a polyol. the

Yet another aspect of the present invention is a method of making a laundry soap bar comprising the steps of:

a) Premixes are prepared by mixing enzymes, stabilizers and polyols as liquid formulations;

b) mixing the premix of step a) with soap;

c) refining the mixture of b) into refined soap; and

d) Compressing the refined soap of step c). the

The present invention also relates to the use of the laundry soap bar of the present invention. the

Detailed description of the invention

definition

Laundry bar:

The term laundry bar or laundry soap bar includes soap bars, combo bars, syndet bars and detergent bars. Laundry bars are used for handwashing laundry. the

introduction

The present invention relates to laundry bars having enzymes incorporated therein. In particular, the present invention relates to the storage stability of laundry bars. the

Although some attempts have been made to improve enzyme stability during the manufacture and storage of laundry bars, the loss of enzyme activity during manufacture and storage in laundry bars remains a significant problem. We have surprisingly found that the stability of the enzyme during the production of laundry bars and after storage can be significantly improved if the enzyme is prepared as a premix before mixing with the soap. the

The present invention also relates to an improved method of incorporating enzymes into laundry bars by which both good enzyme stability and good mixing can be achieved simultaneously to achieve a more homogeneous incorporation. the

It is known practice that the use of dry enzymes in the form of enzyme granules in the preparation of laundry bars provides a protective layer around the enzymes, shielding them from attack by opposing compounds, whereas adding liquid enzymes leaves the enzymes fully exposed to The opposite compound in the detergent matrix, therefore the laundry bar industry is reluctant to use liquid enzymes in the production of laundry bars due to a significant loss of enzyme stability. The disadvantage of using granules is that if they are added during the mixing or molding/milling steps, a portion of the granules will be torn out, thus exposing the enzyme to opposing compounds, also resulting in a substantial loss of enzyme activity, leading to the need for A substantial excess of enzyme granules was added. the

To prevent the granules from breaking down during the mixing and milling steps, granules can be added after the above process steps, as described in WO98/18897, but this will result in an uneven distribution of the enzyme in the laundry bar and the granules will still break up during the molding step crack. the

We have however surprisingly found that by using liquid enzyme products and stabilizing these liquid enzyme products in premix form before mixing them with soap we are able to significantly improve the enzyme stability of laundry bars compared to known products. the

If an enzyme-containing liquid formulation is used instead of the granules, we surprisingly obtain laundry bars with improved enzyme stability compared to conventionally prepared laundry bars using enzyme granules, and also obtain a more stable enzyme in the laundry bars. even distribution. The method of the present invention allows the enzyme to be a liquid formulation which can be added before or during mixing, unlike the method described in WO98/54285. the

It is expected that the use of liquid enzyme formulations will most likely reduce the mechanical stress of the enzyme product compared to when enzyme granules are used, as in conventional enzyme-containing laundry bars. This in turn may reduce the amount of frictional heat developed during mixing. The liquid enzyme formulation also distributes more quickly in the bar, yielding a more homogeneous product in less time, thereby reducing laundry bar preparation time. Liquid enzymes are also readily accessible to added enzyme stabilizers. Proteases, for example, readily gain access to enzyme stabilizers to form Borax complexes within the active site, which lead to reversible inactivation. the

Laundry bars are mainly sold in third world countries, so the cost of laundry bars is a very important factor. With our approach, there is no need to add significant excess enzymes to the laundry bar, which will reduce the final cost of the laundry bar. the

Premix

The premixes of the present invention include enzymes, stabilizers and polyols. The premix may also include pH control compounds. the

In a particular embodiment of the invention, the premix comprises: protease as enzyme; boron-containing compounds such as borate and boric acid as stabilizer; glycerol as polyol; and citric acid or free Fatty acids such as _C12 acids.

Mix the premix thoroughly to obtain a homogeneous mixture before adding to the soap. the

enzyme

An enzyme that can be stabilized by the method of the present invention is any enzyme that exerts its effect during handwashing, for example, cleaning, fabric care, anti-redeposition and stain removal in handwashing applications, and said enzyme is for such purpose And joined. the

An enzyme in the context of the present invention may be any enzyme or a combination of different enzymes. Thus, when an "enzyme" is mentioned, it is generally understood to include a single enzyme or a combination of enzymes. the

It is understood that enzyme variants (eg enzymes produced by recombinant techniques) are also included within the meaning of the term "enzyme". Examples of such enzyme variants are disclosed, for example, in EP 251,446 (Genencor), WO 91/00345 (Novo Nordisk), EP 525,610 (Solvay) and WO 94/02618 (Gist-Brocades NV). the

Enzymes can be classified on the basis of the Handbook of Enzyme Nomenclature from NC-IUBMB, 1992, see also the ENZYME site on the Internet: http://www.expasy.ch/enzyme/ . ENZYME is a repository of information related to enzyme nomenclature. It is mainly based on the recommendation of the Nomenclature Committee of the International Union of Biochemistry and Molecular Biology (IUB-MB), Academic Press, Inc., 1992, which describes the characterized species provided with its EC (Enzyme Commission) number. Each type of enzyme (Bairoch A. The ENZYME database, 2000, Nucleic Acids Res 28:304-305). Such IUB-MB enzymes are named based on their substrate specificity and sometimes their molecular mechanism. This classification does not reflect the structural features of these enzymes.

Some glycoside hydrolases, such as endoglucanase, xylanase, galactanase, mannanase, glucanase and α-semi Another classification of lactosylases into families. They currently fall into 90 different families: see the Internet site of CAZy (ModO) ((Coutinho, P.M. & Henrissat, B. (1999) Carbohydrate-ActiveEnzymes server at URL: http://afmb.cnrs-mrs.fr/～ cazv/CAZY/index.html (corresponding literature: Coutinho, P.M. & Henrissat, B. (1999) Carbohydrate-active enzymes: an integrated database approach. In "Recent Advances in Carbohydrate Bioengineering", H.J.Gilbert, G.Davies, B.Henrissat and B. .Svensson, The Royal Society of Chemistry, Cambridge, pp.3-12; Coutinho, P.M. & Hen-rissat, B. (1999) The modular structure of cells and other carbohydrate-active enzymes: an integrated database approach. In "Genetics, Biochemistry and Ecology of Cellulose Degra-dation″., edited by K. Ohmiya, K. Hayashi, K. Sakka, Y. Kobayashi, S. Karita and T. Kimura, Uni Publishers Co., Tokyo, pp.15-23).

Enzyme types that may be incorporated into laundry bars of the invention include oxidoreductases (EC 1.-.-.-), transferases (EC 2.-.-.-), hydrolases (EC 3.-.-. -), lyase (EC 4.-.-.-), isomerase (EC 5.-.-.-) and ligase (EC62.-.-.-). the

Particularly suitable enzymes include lyases or hydrolases (EC 3.-.-.-), especially proteases, amylases, lipases, pectate lyases, carbohydrases and/or cellulases. the

Preferred oxidoreductases in the context of the present invention are peroxidase (EC 1.11.1), laccase (EC 1.10.3.2) and glucose oxidase (EC 1.1.3.4)]. An example of a commercially available oxidoreductase (EC 1.-.-.-) is Gluzyme ^™ (enzyme available from Novozyme A/S). More oxidoreductases are available from other suppliers. Preferred transferases are transferases of any of the following subclasses:

a Transferase (EC 2.1) that transfers one carbon group;

bTransferases (EC 2.2) that transfer aldehyde or ketone residues; acyltransferases (EC 2.3);

c glycosyltransferase (EC 2.4);

dTransferases that transfer aliphatic hydrocarbon or aryl groups, excluding methyl groups (EC 2.5); and

eTransferases (EC 2.6) that transfer nitrogen-containing groups. the

The most preferred type of transferase in the context of the present invention is transglutaminase (protein-glutamine γ-glutamyltransferase; EC 2.3.2.13). the

Further examples of suitable transglutaminases are described in WO96/06931 (Novo Nordisk A/S). the

Preferred hydrolases in the context of the present invention are: carboxylate hydrolases (EC 3.1.1.-) such as lipases (EC 3.1.1.3); phytases (EC 3.1.3.-), e.g. 3 - phytases (EC 3.1.3.8) and 6-phytases (EC 3.1.3.26); glycosidases (EC 3.2, which fall into the group denoted "glycozymes" in this application), such as alpha-amylases (EC 3.2.1.1); peptidases (EC 3.4, also proteases); and other carbonyl hydrolases. Examples of commercially available phytases include Bio-Feed ^™ phytase (Novozymes), Ronozyme ^™ P (DSM Nutritional Products), Natuphos ^™ (BASF), Finase ^™ (AB Enzymes) and Phyzyme ^™ products series (Danisco). Other preferred phytases include those described in WO 98/28408, WO 00/43503 and WO 03/066847.

In this context, the term "glycosidase" is used not only to denote enzymes that can break sugar chains (such as starch or cellulose), especially five- or six-membered ring structures (ie, glycosidases, EC 3.2), but also to denote Enzymes that can isomerize sugars, for example enzymes that can isomerize a six-membered ring structure such as D-glucose to a five-membered ring structure such as D-fructose. the

Relevant carbohydrases include the following substances (EC numbers in parentheses): α-amylase (EC 3.2.1.1), β-amylase (EC 3.2.1.2), dextran 1,4-α-glucosidase ( EC 3.2.1.3), endo-1,4-β-glucanase (cellulase, EC 3.2.1.4), endo-1,3(4)-β-glucanase (EC 3.2.1.6) , Endo-1,4-β-xylanase (EC 3.2.1.8), Glucanase (EC 3.2.1.11), Chitinase (EC 3.2.1.14), Polygalacturonase (EC 3.2.1.15), lysozyme (EC 3.2.1.17), β-glucosidase (EC 3.2.1.21), α-galactosidase (EC 3.2.1.22), β-galactosidase (EC 3.2 .1.23), starch-1,6-glucosidase (EC 3.2.1.33), xylan 1,4-β-xylosidase (EC 3.2.1.37), endoglucan-1,3-β-D -glucosidase (EC 3.2.1.39), α-dextrin endo-1,6-α-glucosidase (EC 3.2.1.41), sucrose α-glucosidase (EC 3.2.1.48), glucan endo-1 , 3-alpha-glucosidase (EC 3.2.1.59), glucan 1,4-beta-glucosidase (EC 3.2.1.74), endoglucan-1,6-beta-glucosidase (EC 3.2.1.75 ), galactanase (EC 3.2.1.89), arabinan-1,5-α-L-arabinosidase (EC 3.2.1.99), lactase (EC 3.2.1.108), chitosan Chitosanases (EC 3.2.1.132), endo-mannanases (EC 3.2.1.78) and xylose isomerases (EC 5.3.1.5). the

In a particular embodiment of the invention the enzyme is a protease. In a specific embodiment, the enzyme is a bacterial protease. the

Examples of commercially available proteases (peptidases) include Kannase ^™ , Everlase ^™ , Esperase ^™ , Alcalase ^™ , Alcalase Ultra ^™ , Neutrase ^™ , Durazym ^™ , Savinase ^™ , Savinase Ultra ^™ , Ovozyme ^™ , Pyrase ^™ , Pancreatic Trypsin NOVO (PTN), Bio-Feed ^™ Pro and Clear-Lens ^™ Pro (all available from Novozymes A/S, Bagsvaerd, Denmark). Other preferred proteases include those described in WO 01/58275 and WO 01/58276.

Other commercially available proteases include: Ronozyme ^™ Pro, Maxatase ^™ , Maxacal ^™ , Maxapem ^™ , Opticlean ^™ , Propease ^™ , Purafect ^™, and PurafectOx ^™ (available from Genencor International Inc., Gist-Brocades, BASF, or DSM Nutritional Products ).

Examples of commercially available lipases include Lipex ^™ , Lipoprime ^™ , Lipopan ^™ , Lipolase ^™ , Lipolase ^™ Ultra, Lipozyme ^™ , Palatase ^™ , Resinase ^™ , Novozym ^™ 435 and Lecitase ^™ (all available from Novozymes A/S) .

Other commercially available lipases include: Lumafast ^™ (Pseudomonas mendocina lipase from Genencor International Inc.); Lipomax ^™ (alkaligenoid from Gist-Brocades/Genencor Int. Inc. Ps. Pseudoalcaligenes lipase); and Bacillus sp. lipase from Solvay enzymes. More lipases are available from other suppliers.

Examples of commercially available carbohydrases include Alpha-Gal ^™ , Bio-Feed ^™ Alpha, Bio-Feed ^™ Beta, Bio-Feed ^™ Plus, Bio-Feed ^™ Wheat, Bio-Feed ^™ Z, Novozyme ^™ 188, Carezyme ^TM , Celluclean ^TM , Celluclast ^TM , Cellusoft ^TM , Celluzyme ^TM , Ceremyl ^TM , Citrozym ^TM , Denimax ^TM , Dezyme ^TM , Dextrozyme ^TM , Duramyl ^TM , Energex ^TM , Finizym ^TM , Fungamyl ^TM , Gamanase ^{TM , TM} Lactozy, TM Liquezyme ^™ , Maltogenase ^™ , Natalase ^™ , Pentopan ^™ , Pectinex ^™ , Promozyme ^™ , Pulpzyme™, Novamyl ^™ , Termamyl ^{™ ,} AMG ^™ (Amyloglucosidase Novo), Maltogenase ^™ , Sweetzyme ^™ and Aquazym ^™ (all available from / Novozymes A get). Further carbohydrases are available from other suppliers such as the Roxazyme ^™ and Ronozyme ^™ product lines (DSM Nutritional Products), the Avizyme ^™ , Porzyme ^™ and Grindazyme ^™ product lines (Danisco, Finnfeeds), and Natugrain ^™ (BASF), Purastar ^™ and Purastar ^™ OxAm (Genencor).

Other commercially available enzymes include Mannaway ^™ , Pectaway ^™ , Stainzyme ^™ and Renozyme ^™ .

In a particular embodiment of the invention, said enzyme is a protease. the

Protease: Any protease suitable for laundry bars can be used. Suitable proteases include enzymes of animal, vegetable or microbial origin. Microbial sources are preferred. Chemically or genetically modified mutants are included. It may be a serine protease, preferably an alkaline microbial protease or a trypsin-like protease. Examples of alkaline proteases are subtilisins, especially enzymes derived from Bacillus , such as subtilisin Novo, subtilisin Carlsberg, subtilisin 309, subtilisin 147 and subtilisin 168 (described in WO 89/06279).

In a specific embodiment of the invention, the enzyme added to the laundry bar is a mixture of protease and one or more enzymes selected from the group consisting of cellulase, lipase, amylase, pectate lyase and sugar enzyme. the

Enzymes can be incorporated into granules or into liquid formulations. In a particular embodiment of the invention, the enzyme is added to the method of the invention as particles. In another particular embodiment of the invention, the enzyme is added to the method as a liquid formulation. the

stabilizer

The stabilizer of the present invention is a stabilizer capable of stabilizing the enzyme during storage. In a particular embodiment of the invention, the stabilizer is a protease inhibitor. the

Suitable stabilizers include boric acid or derivatives thereof. In a specific embodiment, the stabilizer is boric acid or borate. There are many examples of borate compounds suitable for use in this application. Water-soluble borate compounds such as boric acid are preferred, although other compounds such as borax, boron oxide, borohydride and other alkali metal borates such as sodium orthoborate, sodium metaborate and sodium pyroborate (sodium ortho-, meta and pyroborates) are also preferred. suitable. Substituted boronic acids such as phenylboronic acid, butaneboronic acid and p-bromophenylboronic acid are also useful in this application. Mixtures of the above borate compounds are also suitable for use in this application. the

A suitable enzyme stabilizer may be a phenylboronic acid derivative substituted in the para position with the carbonyl adjacent to the phenylboronic acid. the

Phenylboronic acid derivative enzyme stabilizers have the following formula:

Wherein R is selected from the group consisting of hydrogen, hydroxyl, C ₁ -C ₆ alkyl, substituted C ₁ -C ₆ alkyl, C ₁ -C ₆ alkenyl and substituted C ₁ -C ₆ alkenyl.

In a specific embodiment of the present invention, the premix includes enzyme and the phenylboronic acid derivative enzyme stabilizer disclosed by the above formula, wherein R is C ₁ -C ₆ alkyl, especially, R is CH ₃ , CH _{3 CH2} , _CH3CH2CH2 , _or wherein R _is hydrogen. In a particular embodiment of the invention, the phenylboronic acid derivative enzyme stabilizer is 4-FPBA.

In a particular embodiment of the invention, the laundry bar contains only phenylboronic acid derivatives as enzyme stabilizers. In a more specific embodiment of the invention, the laundry bar contains only 4-FPBA as enzyme stabilizer. the

Stabilizers may be present in amounts of 0.01% to 30% by weight of the total bar composition. In a more specific embodiment, the stabilizer may be present in an amount of 0.05% to 20% by weight of the total bar composition. the

Laundry bars may comprise from 0.1% to 10% w/w of stabilizer of the final bar composition. In a particular embodiment, the laundry bar comprises 0.5% to 5% w/w stabilizer. In a more particular embodiment, the laundry bar comprises 0.5% to 4% w/w stabilizer. In a particular embodiment, the laundry bar comprises at least 0.001% w/w stabilizer. In a specific embodiment, the laundry bar comprises about 4% w/w of stabilizer of the final bar composition. the

Polyol

The polyhydric alcohols that can be used in the present invention are characterized in that they are soluble in water, have a carbon backbone length of C2-C6, and contain multiple hydroxyl groups, preferably 2-6 hydroxyl groups per molecule. the

Polyols that can be used in this application include, but are not limited to: 1,2-butanediol, 3-chloro-1,2-propanediol, ethylene glycol, 1,2-hexanediol, glycerin, mannose, propylene glycol, sorbitol Sugar alcohols, sucrose and mixtures thereof. The polyol level is typically from 0.5% to 10%, preferably from 1% to 5%, more preferably from 1.5% to 3%, by weight of the final bar composition. the

pH Control Compounds

It has been found that lowering the pH is necessary to improve the stability of the enzyme. The pH control agent can be any suitable compound capable of controlling pH. the

In a specific embodiment, the pH control agent is an acid. the

In a specific embodiment, the pH controlling compound may be selected from the group consisting of fatty acids, acetic acid, aconitic acid, adipic acid, arachidic acid, arachidonic acid, aspartic acid, behenic acid, butyric acid, capric acid , caproic acid, cerotic acid, citric acid, formic acid, fumaric acid, glutamic acid, glutaric acid, glyceric acid, glyceric acid-3-phosphate, glycolic acid, isocitric acid, α-oxopentadiene Acid, lactic acid, lauric acid, linoleic acid, linolenic acid, maleic acid, malic acid, malonic acid, myristic acid, oleic acid, oxalic acid, oxaloacetic acid, palmitic acid, palmitoleic acid, phosphatidic acid, phosphatidic acid Alcohols pyruvic acid, pimelic acid, propionic acid, pyruvic acid, stearic acid, succinic acid, tartraic acid and valeric acid. the

The pH control agent will generally be present at a level of 0.05% to about 8%, preferably 0.1% to 6%, more preferably 0.2% to about 4% by weight of the final bar composition. In a particular embodiment, the amount of pH control agent is from 0.001% to 5% w/w of the bar. In a more particular embodiment, the amount of pH controlling agent is from 0.01% to 2% w/w of the bar. In a most particular embodiment, the amount of pH controlling agent is from 0.05% to 1% w/w of the bar. In a specific embodiment, the amount of pH controlling agent is about 0.2% w/w of the final bar composition. the

moisture content

Moisture enhances the mixing of premix ingredients. Moisture also provides the laundry bar with an acceptable feel and other physical properties. Moisture, such as water, can be added to the premix by inclusion in the ingredients and/or as free water. the

Laundry bars contain from about 5% to about 30%, preferably from about 10% to about 25%, moisture by weight of the final bar. the

Laundry Bar Ingredients

The laundry bars of the present invention include a premix and soap. Laundry bars may also include complexing agents such as EDTA and EDHP, fragrances and/or various fillers. the

additional compound

Laundry soap bars can include additional compounds. The compounds are not limited to surfactants such as anionic synthetic surfactants, builders/builders, polymeric soil release agents, detergent chelants, glycerin, stabilizers, Extenders, dyes, colorants, dye transfer inhibitors, alkoxylated polycarbonates, suds suppressors, structurants, binders, filter aids/leaching agents, bleach activation agent, clay remover (clay soil removal agent), anti-redeposition agent, polymeric dispersant, brightener (brightener), fabric softener, perfume and/or other compounds known in the art. the

soap (soap)

Soaps suitable for use in accordance with the present invention include water-soluble salts of higher fatty acids. Soaps can be produced by direct saponification of fats and oils or by neutralization of free fatty acids. Suitable soaps are the sodium, potassium, ammonium and alkyloammonium salts of higher fatty acids containing about 8-24 carbon atoms, such as 12 to about 18 carbon atoms. In a particular embodiment, the soap is selected from the sodium and potassium salts of fatty acid mixtures derived from coconut oil and tallow, such as the sodium or potassium salts of tallow and palm oil. Additionally, nut oils can be added like coconut oil or palm kernel oil at 5-30% by weight of the final bar. the

Glycerin

In known soap making processes, glycerin is either removed for commercial reasons or left in the soap. Soaps can therefore be described as high or low glycerin soaps. Low glycerin soaps contain 0 to 2% glycerin, if more glycerin is needed, it can be added during the soap making process while the soap is still liquid to ensure proper uptake or to the soap noodle. In a specific embodiment, the laundry soap bar comprises 1 to 6% glycerin. In a more specific embodiment of the present invention, the laundry soap bar comprises 2% to 5% glycerin by weight of the total bar. In a most specific embodiment, the laundry soap bar comprises about 4% glycerin. the

Surfactant

Synthetic anionic surfactants suitable for use herein include water soluble salts, preferably alkali metal, ammonium and alkylammonium salts of organosulfur reaction products having from about 10 to about 20 Alkyl groups of carbon atoms and sulfonic acid or sulfate groups. Examples of such synthetic surfactants are sodium and potassium alkyl sulfates, especially those produced by reducing higher alcohols ( _C8-18 carbon atoms), such as glycerides of tallow or coconut oil. those obtained by the sulfation of alcohols; and sodium and potassium alkylbenzene sulfonates, wherein the alkyl group contains from about 9 to about 15 carbon atoms in a straight or branched chain configuration. Of particular value are the linear linear alkylbenzene sulfonates (LAS) in which the average number of alkyl carbon atoms is about 11-13, abbreviated as _C11-13 LAS. Preferred are the alkali metal, especially sodium, salts of these surfactants.

Other examples of anionic synthetic detergents suitable for use herein are sodium alkyl glyceryl ether sulfonates (AES), especially ethers of higher alcohols derived from tallow and coconut oil; Sodium glyceride sulfonate and sodium coconut oil fatty acid monoglyceride sulfonates and sulfates; and sodium or potassium salts of alkyl ethyleneoxide ether sulfates ) containing from about 1 to about 10 units of ethylene oxide per molecule, and wherein the alkyl group contains from about 10 to about 20 carbon atoms. the

In addition, suitable anionic synthetic detergents also include water-soluble salts of alpha-sulfonated fatty acid esters containing from about 6 to about 20 carbon atoms in the fatty acid group and from about 1 to about 10 carbon atoms in the ester group. carbon atoms; water-soluble salts of 2-acyloxyalkane-1-sulfonic acid containing from about 2 to about 9 carbon atoms in the acyl group and containing in the alkane moiety from about 9 to about 23 carbon atoms; water-soluble salts of alkenes and paraffin sulfonates containing from about 12 to about 20 carbon atoms; and beta-alkyloxy alkane sulfonates, which Contains from about 1 to about 3 carbon atoms in the alkyl and from about 8 to about 20 carbon atoms in the alkane moiety. the

Examples of preferred anionic synthetic surfactants are C _10-18 alkyl sulfate (AS), C _10-18 linear alkylbenzene sulfonate (LAS), C _10-14 alkyl glyceryl ether sulfonate (AES) ), and their mixtures.

Examples of components contained in conventional laundry bars (synthetic detergent bars) are: linear alkylbenzene sulphonate, coco fatty alcohol sulphate, soda ash, sulfuric acid, sodium tripolyphosphate, carbonic acid Calcium, Coco Fatty Alcohol, TiO ₂ , Cellulase, Diethylene Triamine (Methylene Phosphonic Acid), Coco Monoethanolamide, Fluorescent Agents, Substituted Methyl Cellulose, Fragrance, moisture.

Examples of detergent components contained in conventional laundry bars (combo bars) are: LAS, Soap, Cellulase, Protease, Boric Acid, Borax, Sodium Formate, Sodium Citrate, Sodium Carbonate, Glycerin, Propylene Glycol, Ethylene Glycol, MgSO _4. Soda ash, STPP, talc, water.

Preparation of laundry bars

The laundry bars of the present invention can be processed in conventional laundry bar manufacturing equipment such as, but not limited to: mixers, plodders (e.g. two-stage vacuum molding machines), extruders, Cutting machines, logo-stampers, cooling tunnels and packaging machines. the

Prepare the premix before adding it to the soap. the

According to the present invention, the method is a method of incorporating an enzyme into a laundry soap bar and also maintaining enzyme activity. the

The inventive method is used for preparing laundry soap bar, and it comprises the following steps:

a) Premixes are prepared by mixing enzymes, stabilizers and polyols as liquid formulations;

b) mixing the premix of step a) with soap;

c) refining the mixture of b) into refined soap; and

d) Compressing the refined soap of step c). the

The premixes of the present invention can be added to the soap at various stages in the process. In a particular embodiment of the invention, the premix is added to the soap prior to the refining step. the

In a specific embodiment of the present invention, it also includes adding a pH control agent in step a). the

The mixing of the premix, step a) can be carried out in a mixer, for example in a mixer of the type Double Sigma Amalgator MSA-100. The mixing step a) preferably lasts not longer than 1 minute, 5 minutes, 10 minutes, 15 minutes, 30 minutes, 45 minutes, not longer than 1 hour. the

After the premix is prepared, it can be stored until it is used for the production of laundry bars, or it can be used immediately for the production of laundry bars. After the premix is prepared, it is metered into the soap. In a specific embodiment, the premix is mixed with the soap in a refining step prior to molding to ensure proper incorporation of the premix into the soap. The refining step can be performed by an in-line refiner or a press with a screen installed in the head, or by refining in a final press. the

The molding step is carried out in a molding press such as a Duplex plodder. Preferably, the molding press is operated under high vacuum, whereby entrapped air/gas is removed. the

The product is extruded and the extruded strands are then sent to a cutting machine where the strands are cut into the desired strand lengths. Optionally, the bars are stamped into the final shape in a stamping press. High-speed embossing machines are often used in high-volume production lines. Preferably the high speed press has a cooled die. The laundry bar may be cooled, such as in a cooling tunnel, before it is conventionally followed by packaging, boxing and sending for storage. the

Additional compounds may be added to the mixture comprising soap and premix. These compounds include, but are not limited to, brighteners, colorants, structurants, binders, photoactive bleaches, soil release polymers and anti-redeposition agents. the

Application of laundry bars

The laundry bar of the present invention is used for hand washing laundry or for washing dishes. the

The present invention is further described by the following examples, which should not be construed as limiting the scope of the invention. the

Example

Example 1

This example shows a general method for making an enzyme-containing soap bar, where the various ingredients are added to the soap separately. the

Each stabilizing ingredient was added to the soap separately. the

Three different proteases were tested:

0.2% EVERLASE 16L by weight of the final laundry bar;

0.2% SAVINASE 16L by weight of the final laundry bar;

0.2% SAVINASE ULTRA 16L by weight of the final laundry bar. the

These proteases were added to the soap at room temperature (RT) and mixed. Separately, 2% glycerin and 0.2% citric acid were added to the soap and mixed. the

Add 2% sodium borate to the mixture containing Everlase 16L and Savinase 16L. the

This mixture is transferred to a refiner, then to a molding press, where it is finally embossed. the

Stability results are shown as percent residual enzyme activity after storage at 35°C for 2, 4, 6 or 8 weeks. the

If no loss of activity occurred, then the theoretical residual activity (100%) due to water loss of the soap during storage should be as shown in the table below. the

Storage of soap in an open climate chamber will always result in evaporation of water from the bar, causing weight loss. the

Example 2

In this example, the stabilizer was added to the premix, which was then mixed with the soap without refining. the

The components of the premix are:

EVERLASE 16L 0.2%,

Glycerin 2%,

Borax 2%,

Citric acid 0.2%. the

The ingredients of the premix are blended in a mixer to make a slurry, which is then added directly to the soap. This mixture is sent directly to a molding press, whereupon the product is embossed. the

These results show that the storage stability is surprisingly high. the

Example 3

Stabilizers are added to the premix, which is then added to the soap while refining it into a thin noodle, which is then sent to a molding press for final soap extrusion. It is then embossed. the

The components of the premix are:

EVERLASE 16L 0.2%,

Glycerin 2%,

Borax 2%,

Citric acid 0.2%. the

The results were again compared to the theoretical maximum activity achievable due to water loss from the soap. the

High storage stability is maintained. the

Example 4

A premix containing stabilizer was prepared. The components are:

EVERLASE 16L 0.2%,

Glycerin 2%,

Borax 2%,

EDHP 0.05% and EDTA 0.05%,

Citric acid 0.2%. the

The premix is added to the soap while refining it into a fine soap base, which is then fed into a molding machine for final soap extrusion. Here the complexing agents EDHP and EDTA are added for the purpose of oxidation protection. the

The results were again compared to the theoretical maximum activity achievable due to water loss from the soap. the

The complexing agent has an initial negative effect on the storage stability (titration activity), however the storage stability remains constant over the entire period. the

Example 5

Prepare a premix by mixing the following ingredients:

EVERLASE 16L 0.2%,

Glycerin 2%,

Borax 2%,

Citric acid 0.2%. the

In the two-step process, the premix is added to the fraction that breaks down the soap base. This mixture was added to a mixer, molded and stamped. We expect absorption of soap material to occur during production scale processing. To improve the absorption, refining is added in one of the molding steps followed by final extrusion, or mixing followed by molding (depending on the line). the

The results were again compared to the theoretical maximum activity achievable due to water loss from the soap. the

Once again a perfect match to the theoretical 100% stability level. the

Example 6

Stabilizers are added to the premix, which is then added to the soap while refining it into a fine soap base, which is sent to a molding press for final soap extrusion and embossing. the

Each group is divided into:

EVERLASE 16L 0.2%,

Glycerin 2%,

Boric acid 2%. the

The results were again compared to the theoretical maximum activity achievable due to water loss from the soap. the

Example 7

The components of the premix are

EVERLASE 16L 0.2%,

Glycerin 2%,

Boric acid 1.3%,

Borax 0.7%. the

A premix is prepared by mixing, which is then added to the soap while refining to a fine soap base, and this mixture is added to the final soap extrusion. the

The results were again compared to the theoretical maximum activity achievable by dry water loss from the soap. the

This combination also gives very good stability. the

Claims (35)

1. A method of preparing a laundry soap bar, comprising the steps of: a) A premix is prepared by mixing as a liquid formulation an enzyme, a stabilizer, a pH control agent, water and a polyol, wherein the stabilizer is present in an amount of 0.5% to 5% by weight of the final bar composition, which is borate, boric acid, borax, or a derivative of phenylboronic acid having the formula; Wherein R is selected from the group consisting of hydrogen, hydroxyl, C ₁ -C ₆ alkyl, substituted C ₁ -C ₆ alkyl, C ₁ -C ₆ alkenyl and substituted C ₁ -C ₆ alkenyl; The pH control agent is an acid which is present at a level of 0.01% to 2% w/w of the bar; The polyol is characterized by being soluble in water, having a carbon backbone length of _C2 - _C6 , containing multiple hydroxyl groups, and having a polyol level of 1%-5% by weight of the final bar composition. b) mixing the premix of step a) with soap; c) refining the mixture of b) into refined soap; and d) Compressing the refined soap of step c). 2. The method of claim 1, wherein the acid is citric acid. 3. The method of claim 1, wherein the pH control agent is present at a level of 0.05% to 1% w/w of the bar. 4. The method of claim 2, wherein the pH control agent is present at a level of 0.05% to 1% w/w of the bar. 5. The method of claim 1, wherein the enzyme in the mixture is a protease. 6. The method of claim 2, wherein the enzyme in the mixture is a protease. 7. The method of claim 3, wherein the enzyme in the mixture is a protease. 8. The method of claim 4, wherein the enzyme in the mixture is a protease. 9. The method of any one of claims 5-8, wherein the protease is a bacterial protease. 10. The method of claim 9, wherein the bacterial protease is alkaline protease. 11. The method of claim 10, wherein the alkaline protease is a subtilisin. 12. The method of any one of claims 5-8, wherein the mixture further comprises an enzyme selected from the group consisting of cellulase, lipase, amylase, pectate lyase, and carbohydrase. 13. The method of any one of claims 1-8, wherein the stabilizer is 4-formyl-phenylboronic acid. 14. The method of any one of claims 1-8, wherein the stabilizer is boron oxide, borohydride, sodium orthoborate, sodium metaborate, sodium pyroborate, phenylboronic acid, butaneboronic acid, or p-bromobenzene Boronic acid. 15. The method of claim 1, wherein the stabilizer is present in an amount of 0.5% to 4% w/w of the final bar composition. 16. The method of any one of claims 1-8, wherein the polyol is glycerol. 17. The method of claim 16, wherein the laundry soap bar comprises 2% to 5% glycerin. 18. The method of claim 17, wherein the laundry soap bar comprises 4% glycerin. 19. Laundry bar obtainable by the method of any one of claims 1-8. 20. A premix for use in the method of any one of claims 1-8, consisting of enzymes, stabilizers, pH control agents, water and polyols, wherein the stabilizers are by weight of the final bar composition present in an amount of 0.5% to 5%, which is a salt of borate, boric acid, borax, or a derivative of phenylboronic acid having the formula;

Wherein R is selected from the group consisting of hydrogen, hydroxyl, C ₁ -C ₆ alkyl, substituted C ₁ -C ₆ alkyl, C ₁ -C ₆ alkenyl and substituted C ₁ -C ₆ alkenyl; The pH control agent is an acid which is present at a level of 0.01% to 2% w/w of the bar; The polyol is characterized by being soluble in water, having a carbon backbone length of C2-C6, containing multiple hydroxyl groups, and having a polyol level of 1%-5% by weight of the final bar composition. 21. The premix of claim 20, wherein the acid is citric acid. 22. The premix of claim 20, wherein the pH control agent is present at a level of 0.05% to 1% w/w of the bar. 23. The premix of claim 20, wherein the stabilizer is 4-formyl-phenylboronic acid. 24. The premix of claim 20, wherein the stabilizer is boron oxide, borohydride, sodium orthoborate, sodium metaborate, sodium pyroborate, phenylboronic acid, butaneboronic acid, or p-bromophenylboronic acid. 25. The premix of claim 20, wherein the stabilizer is present in an amount of 0.5% to 4% w/w of the final bar composition. 26. The premix of any one of claims 20-25, wherein the enzyme is a protease. 27. The premix of claim 26, wherein the protease is a bacterial protease. 28. The premix of claim 27, wherein the bacterial protease is alkaline protease. 29. The premix of claim 28, wherein the alkaline protease is a subtilisin. 30. The premix of any one of claims 27-29, wherein the premix further comprises one or more enzymes selected from the group consisting of cellulase, lipase, amylase, pectate cleavage Enzymes and carbohydrases. 31. The premix of any one of claims 20-25 and 27-29, wherein the polyol is glycerol. 32. The premix of claim 30, wherein the polyol is glycerin. 33. The premix of claim 31, wherein the laundry soap bar comprises 2% to 5% glycerin. 34. The premix of claim 33, wherein the laundry soap bar comprises 4% glycerin. 35. Use of the laundry bar of claim 19 for hand laundry.