Title of Invention

"A PROCESS FOR MAKING LOW MOISTURE LAUNDRY DETERGENT BAR" "

Abstract

The present invention relates to a laundry detergent bar composition having from 0.5% to 60% anionic synthetic detergent surfactant, from 0.10% to 60% bleach agent, no more than about 3.5% moisture in the finished bar composition, from 0.1% to 10% non-liquid, thixotrophic binding agents, and the balance being the optional components. The present invention also relates to a process for making the bar composition having the steps of mixing a dry form and a neutralized paste form of a sodium salt of fatty alcohol sulfate in the presence of sodium carbonate, and a polyphosphate builder, reacting alkyl benzene sulfonic acid with the mixture, such that the acid is completely neutralized by the sodium carbonate, adding a non-liquid, thixotrophic binding agent and optional components, then milling and plodding the mixture to form bars.

Full Text

FIELD OF THE INVENTION This invention relates to a process for making low moisture laundry detergent bar with improved bleach stability. The process to make such composition is also included herein. BACKGROUND OF THE INVENTION 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), and Indian Patent 165353, Hindustan Lever. It has now been found that laundry bar compositions containing a low moisture content of no more than about 3.5% in the finished product composition delivers significant improvement in bleach stability in bars over time. SUMMARY OF THE INVENTION The present invention relates to a laundry detergent bar composition comprising: (a) from about 0.5% to about 60% anionic synthetic detergent surfactant, (b) from about 0.10% to about 60% bleach agent, (c) no more than about 3.5% moisture in the finished bar composition, and (d) from about 0.1% to about 10% non-liquid, thixotrophic binding agents. All documents referenced herein are incorporated by reference. According to the present invention there is provided a process for making low moisture laundry detergent bar, which comprises: (a) mixing a dry form and a neutralized paste form of a sodium salt of fatty alcohol sulfate in the presence of sodium carbonate, and a polyphosphate builder, (b) reacting alkyl benzene sulfonic acid with the mixture in (a), such that the acid is completely neutralized by the sodium carbonate, so as to obtain .5 to 60% wt. of surfactant; (c) adding 0.1% to 10% wt. of a non-liquid, thixotrophic binding agent; and optional components such as herein described, and (d) milling and plodding the mixture of (c) to form bars, wherein the total amount of moisture in the components added in Steps (a) to (c) is no more than about 3.5% of the moisture formed in (c). 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. In accordance with the present invention it has been found that a laundry detergent bar can achieve bleach stability over time in a low moisture content bar composition. Anionic synthetic detergent surfactants Anionic synthetic detergent surfactants which are suitable for use herein include the water-soluble salts, preferably the alkali metal, ammonium and alkylolammonium salts of organic sulfuric reaction products having in their molecular structure an alkyl group containing from about 10 to about 20 carbon atoms and a sulfonic acid or sulfuric acid ester group. (Included in the term "alkyl" is the alkyl portion of acyl groups.) Examples of this group of synthetic surfactants are the sodium and potassium alkyl sulfates, especially those obtained by sulfating the higher alcohols (Cg.jg carbon atoms) such as those produced by reducing the glycerides of tallow or coconut oil; and the sodium and potassium alkylbenzene sulfonates in which the alkyl group contains from about 9 to about IS carbon atoms, in straight chain or branched chain configuration, e.g., those of the type described in U.S. Patents 2,220,099 and 2,477,383. Especially valuable are linear straight chain alkylbenzene sulfonates in which the average number of carbon atoms in the alkyl group is from about 11 to 13, abbreviated as C 11.13 LAS. The alkali metal salts, particularly the sodium salts of these surfactants are preferred. Alkylbenzene sulfonates and processes for making them are disclosed in U.S. Patent Nos. 2,220,099 and 2,477,383. Other synthetic anionic surfactants suitable for use herein are the 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. Preparation of alkyl glyceryl ether sulfonates are described in detail in U.S. Pat. 3,024,273, Whyte et al., issued March 6, 1962. In addition, suitable synthetic anionic surfactants include the water-soluble salts of esters of alpha-sulfonated fatty acids containing from about 6 to 20 carbon atoms in the fatty acid group and from about 1 to 10 carbon atoms In the ester group; water-soluble sails of 2-acyloxyalkane-l-sulfonlc acids containing from about 2 to 9 carbon atoms in the acyl group and from about 9 to about 23 carbon atoms in the alkanc moiety; water-soluble salts of olefin and paraffin sulfonates containing from about 12 to 20 carbon atoms; and bcia-alkyloxy alkane sulfonnlcs containing from about 1 to 3 carbon atoms in the alkyl group and from about 8 to 20 carbon atoms in the alkane moiety. Preferred luiiordo surfactants are C10-18 linear alkyl benzene sulfonates, C10-18 alkyl sulfates, and mixtures tliereof. The amount of anionic surfactant in the compositions herein is from about 0.5% to about 60%, preferably from about 10% to about 30%. Bleach 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 the bletfch agents useful for detergent compositions in textile cleaning, hard surface cleaning, or other cleaning purposes that are now known or become known, Mixtures of bleach agents can also be used, A useful bleach agent that can be used encompasses pcrcarboxyllc acid bleach agents and salts thereof. Suitable examples of this class of agents include magnesium rnonoperoxyphthalate hcxahydratc, the magnesium suit of mctuchloro porbcnzoic acid, 4-nonylamlncHt-oxoperoxybutyric acid and dipcroxydodecancdioic acid, Such bleach agents are disclosed in U.S. Patent 4,483,781, Hartman, issued November 20, 1984, U.S. Patent Application 740,446, Bums 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-nonylriniino-6-oxopcroxycnproic ncid as described in U,S, Patent 4,634,551, issued January 6, 1987 to Burns et al. Other peroxygen bleach agents can also be used, Suitable peroxygen bleach compounds include sodium carbonate pcroxyhydmtc and equivalent "ncrcarbonate" bleaches, sodium pyrophospluttc peroxyhydrate, urea peroxyhydrate, and sodium peroxide. Persulfate bleach (e.g., OXONE, manufactured commercially by DuPont) can also be used. Bleach agents other than oxygen bleach agents are also known in the art and can be utilized herein, One typo 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 sulfonatc zinc phthalocyanine. A useful pcrcuiuonale blench comprises diy particles having nn 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, boratc or water-soluble surfactants. Percarbonate is available from various commercial sources such as FMC, Solvay and Tokal Denka, The preferred bleach agent for the present invention are those peroxygcn 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 pcrsalt bleaching compounds, such as the alkali metal perborates, percarbonates, pcrphosphates, and the like. Mixtures * of two or more such bleaching compounds cart also be used, if desired, Preferred peroxygcn 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, uiea peroxyhydrate, and sodium peroxide. Particular preferred are sodium perborate tcirahydrate, and especially, sodium perborate _ monohydrate. Sodium perborate jnonohydrate is especially preferred because it is very stable during storage and yet still dissolves very quickly in the bleaching solution, Bar Physical Properties The Anal bar composition should have no more than about 3.5% moisture, Preferably, the bar will contain from about 0.5% to about 3,4% moisture, more preferably, 1.4% to 3%, The moisture level can be determined by arty methods known in the art by one skilled in the area of laundry bar compositions. One common method is the Bidwell Sterling Distillation method. Another known method is the Karl Fischer Moisture Titration Method. See AOCS official method Dd2a-59 issue 93 and AOCS official method Dd2b-59 issue 89, Although the bar has low moisture, It still has acceptable physical properties In terms of hardness and binding due to the addition of from about 0.1% to about 10% of a non-liquid, tluxotrophic binding agent. The binding agent is a non-liquid at ambient temperature, As used herein, "non-liquid" means having a melting point above 38° C, Preferred levels of the binding agent arc from about 0.5% to about 5%, most preferably from about 1% to about 2.5%, Binding agents hold (he bar together in a cohesive, soluble form. The binding agent is non-liquid, having a moisture level of less than 0,5%, preferably 0% in the agent material. The binding agent has thixotroplvic properties, meaning that when shear force is applied to the binding agent, the material becomes fluid and helps the binding of the bar ingredients, Acceptable binding agents include precipitated silica, C8-C18 fatty add alkanol amides, natural and synthetic starches (plain or modified), guar gums and derivatives of gtiar gums, dextrin, polyethylene glycol (M.W. 1500-20,000) and mixtures thereof, Preferably, the binding ngent is a fatty acid alkanol amide, where the alkanol can be an ethanol, methanol or propanol. The alkanol amide can be a di-alkanol or monc-alkanol amide. Most preferably, the binding agent is coco monocthnnolamidc. The types and amount of binder chosen CAR affect bar hardness, Preferably, the amount of any particular binder (within tlie above-described * percentage ranges) should be chosen so as to provide a bar hardness (measured by the penctrometer) of about 1.1 to 2.2 mm after 24 hours of aging of the bar under normal atmospheric conditions, Adjunct Inpredients Optional Surfactants The detergent bars of the present invention can contain optional ingredients commonly used in detergent products, A typical listing of the classes and species of optional surfactants, (e.g. « noruonic, zwitterionic and amphoteric surfactants) optional alkaline builders such as sodium carbonate trisodium phosphate sodium silicate, etc. and other ingredients useful herein appears in U.S. Pat. No, 3,664,961, issued to Norris on May 23, 1972, and EP 550,652, published on April 16, 1992, Such optional surfactants, if present, can be included at levels up to a total of about 10%, preferably about 0.5-3%. * In addition, a hydrotrope, or mixture of hydrotropes, can be present in the laundry detergent bar. Preferred hydrotropes include the alkali metal, preferably sodium, salts of toluene sulfonate, xylcno sulfonatc, cumenc sulfonato, sulfosuccinnto, and mixtures thereof. Preferably, the hydrotrope is added to the linear alkyl benzene sulfonic acid prior to its neutralization. The hydrotrope, if present, will preferably be present at from about 0,5% to about 5% of the laundry detergent bar, Builders The laundry bars of the invention can contain from about 0% to about 60%, preferably from about 5% to about 25% detergent builder. These detergent builders can be, for example, water-soluble alkali-metal salts of phosphate, pyrophosphates, orthophosplintcs. tripolyphofipltateu, higher polypbosphates, and mixtures thereof, Preferred builders are a water-soluble alkali-metal salt of tripolyphosphnte, and a mixture of tripolyphosplvale and pyrophospliatc, The builder can also bo a non-phosphate detergent builder. Specific examples of non-phosphate, 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. Specific preferred examples of builders include sodium tn'polyphosphates (STPP) and tetra sodium pyrophosphates (TSPP), and mixtures thereof, Other specifically preferred examples of builders include zeolites and polycarboxylates. Sodium carbonate is a particularly preferred ingredient in the subject invention compositions, since in addition to its use as ajbuildcr, it can also provide alkalinity to the composition for improved detergency, and also can serve as a neutralizing agent for acidic components added in the composition processing. Sodium carbonate is particularly preferred as a neutralizing inorganic salt for an acid precursor of an anlonic siufhctant u.sed in such composition such 05 the nlkyl ether sulfuric acid and alkylbenzene sulfonic acid. Co-polymers of acrylic acid and maleic odd nre preferred in the subject compositions as auxiliaiy builders, since it lias been observed that their use in combination with fabric softening clay and clay flocculating agents further stabilizes and improves the clay deposition and fabric softening performance. Fabric Softening Clay The fabric softening clay is preferably a smectite-type clay. The smectite-type clays can be described as expandable, three-layer clays; i.e., alumino-silicates and magnesium silicates, having an ion exchange capacity of at least about 50 rneq/100 g. of clay. Preferably the clay particles are of a size that they can not bo perceived Wctilcly, so ns not to Iwvo a griity fed on the treated fjibric of the clothes. The fabric softening clay can be added to the bar to provide about 1% to about 50% by weight of the bar, moro preferably from about 2% to about 20%, and most preferably about 3% to While any of the smectite-type clays described herein are useful in the present invention, certain clays are preferred. For example, Gelwhite GP is an extremely white form of smectite-type clay and is therefore preferred when formulating white granular detergent compositions, Volclay BC, which is a smectite-type clay mineral containing at least 3% iron (expressed as Fe2O3) in the crystal lattice, and which has a very high ion exchange capacity, is one of the most efficient and cflective clays for use in the instant compositions from the standpoint of product performance. On the other band, certain smectite-type clays are sufficiently contaminated by other silicate minerals that their ion exchange capacities fall below the requisite range; such clays are of no use in the instant compositions. Clay Flocculating Agent It has been found that the use of a clay flocculating agent in a laundry bar containing softening clay provides surprisingly improved softening clay deposition onto the clothes and clothes softening performance, compared to that of laundry bars comprising Boftcriing clay alone, The polymeric clay flocculating agent is selected to provide improved deposition of the fabric softening clay. Typically such materials have a high molecular weight, greater than about 100,000. Examples of such materials can include long chain polymers and copolymcrs derived from monomers such as ethylcne oxide, acryJamide, acrylic acid, dimethylamino ethyl methacrylate, vinyl alcohol, vinyl pyrrolidoDC, and ethylene imiae. Gums, like guar gums, are suitable as well. The preferred clay flocculating agent is a poly(ethylene oxide) polymer. The amount of clay flocculating agent, if any, is about 0.2-2%, preferably about 0.5-1%, Soil Suspending Agent; Soil suspending agents can be used. In the present invention, their use is balanced with the fabric softening clay/clay flocculating agent combination to provide optimum cleaning and fabric softening performance. Soil suspending agents can also include water-soluble salts of carboxyincthylcellJilose and carboxyhydroxymcthyicellulose. A preferred soil suspending agent is an acrylic/malcic copolymcr, commercially available as Sokolan®, from BASF Corp. Other soil suspending agents include polyethylene glycols having a molecular weight of about 400 to 10,000, and cthoxylated mono- and polyamines, and quaternary salts thereof. If included, it can be at levels up to about 5%, preferably about 0.1-1%, Other OndonaL Adjunct Inrjedlonts A particularly preferred optional component of the present invention is a detergent cholant Such chclants ore able to sequester and chelate alkali cations (such as sodium, lithium and potassium), alkali metal earth cations (such as" magnesium and calcium), and most importantly, heavy •metal cations such as iron, manganese, zinc and aluminum. Preferred cations include sodium, magnesium, zinc, and mixtures thereof, Tho detergent chelant is particularly beneficial for maintaining good clouting performance and improved surfactant mileage, despite the presence of the softening clay and the clay flocculating agent The detergent chelant is preferably a phosphonate chelant, particularly one selected from the group consisting of dicthylenotriamine pcnta(methylene phosphonic acid), ethylene diaminc tetra(methylcne phosphonic acid), and mixtures and salts and complexes thereof, and an acetate chelant, particularly one (elected from the group consisting of diethylenctriamine pcnta(acctic acid), ethylene diarainc tctra(acctic 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 cnelant can be included in the laundry bar at a level up to about 5%, preferably from about 0,1% to about 3%, more preferably from about 0.2% to about 2%, most preferably from about 0.5% to about 1.0%. 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. 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, if any, is present 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 a laundry bar as free fatty alcohol. However, low levels of fatty alcohol can be introduced into the bars as impurities or as unrcacted 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 sulfato basis. Another preferred optional componctit in the laundry bar is 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 ftom depositing on the fabrics, and dccolorization DTI materials capable of decolorizing UK fugitives dye by oxidation. An example of a decolorization DTI is hydrogen peroxide or a source of hydrogen peroxide, such as pcrcarbonate or perborate, Non-limiting examples of polymeric DTI materials include polyvinylpyrridino N-oxide, polyvinylpyrrolidone (PVP), PVP-polyvinylimidazoIc copolymer, and mixtures thereof. Copolymers of N'vinylpynolidonc and N-vinylimidazole polymers (referred to as "PVPl") are also preferred for use herein. The amount of DTI included in the subject composltiona, if any, is about 0,05-5%, preferably about 0.2-2%, Another preferred optional component in the laundry bar is a secondary fabric softener component in addition to the softening clay. Such materials can be used, if any, at levels of about 0,1% to 5%, more preferably from 0.3% to 3%, and can include: amines of the formula R4R5R6N, wherein R4 is C5 to C22 hydrocarbyl, R5 and R6 are independently C1 to C10 hydrocarbyl. One preferred amine is ditallowmethyl aminc; complexes of such amines with fatty acid of the formula R7COOH, wherein R7 is C9 to C22 hydrocarbyl, as disclosed in EP No. 0,133,804; complexes of such amines with phospliate esters of the formula R8O'P(O)(OH)-OR9 and IIO-P(O)(OH)-OR9, wherein R8 and R9 are independently C1 to C20 alkyl of alkyl ethoxylate of the formula -alkyl-(OCH2CH2)', cyclic amines such as imidazolines of the general formula 1-(higher alkyl) amido (lower alkyl)-2-(higher alkyl)imidazoline, where higher alkyl is from 12 to 22 carbons and lower alkyl is from 1 to 4 carbons, such as described in UK Patent Application GB 2,173,827; and quaternary ammonium compounds of the formula Rl0RllRl2Rl3N+X, wherein R10 is alkyl having 8 to 20 carbons, R11 is alkyl having 1 to 10 carbons, R12 and R13 arc alkyl having 1 to 4 carbons, preferably methyl, and X is an anion, preferably CI" or Br", such as C12-13 alkyl trimcthyl ammonium chloride. 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 sulfonau'on processes, or it can be added separately, Oilier filler materials include bcntonite and talc. Calcium carbonate (also known as Calcarb) is also a well known and often used filler component of laundry bars. Fillers include minerals, such as talc and hydrated magnesium silicate-containing minerals, where the silicate is mixed with other minerals, c,g,, old mother rocks such as dolomite. Filler materials are typically used, if included, at levels up to 40%, preferably from about 5%tonbout 2.5%. Optical brightencrs are also preferred optional ingredients in laundry bars of the present invention. Preferred optical brightencrs are diamino stilbcne, disryrilbiphenyl-type optical brighteners, Preferred as examples of such brightcners are 4,4'-bis{[4-anilino-6-bis(2-hydoxyethyl) aminO'l,3,5-trizin-2-yl]amino}stilbcne-2,2'-disijlfoiuc acid disodium salt, 4-4'-ui£(2-sulfostyryl) biphenyl and 4,4l-bis((4.aiu'lino-6-morpholino-l,3,5-triazin-2'yl) amino)stilbene-2,2'-disulfonic acid dlsodlum salt Such optical brighlciusrfi, or mixtures theieof, can be used at levels in die bar of from about 0.05%-1.0%. Dyes, pigments, germicides, and perfumes can also be added to the bar composition, If Included, they are typically at levels up to about 0.5%. Another optional component of the subject invention composition is a photoblcach material, particularly phtholocyaninc photoblcqches which aro described in US, Patent 4,033,718 Issued July 5, 1977, incoiporated herein by reference. Preferred photobleachcs are metal phthalocyanino compounds, the metal preferably having a valance of +2 or +3; zinc and aluminum are preferred metals. Such photoblcaches are available, for example, under the tradcname TINOLUS or as zino phthalocyaru'ne sulfonate. The photobleach components, if included, are typically in the subject compositions at levels up to about 0.02%, preferably from about 0.001% to about 0.015%, more preferably from about 0.002% to about 0.01%. Another useful optional component of the subject compositions are detergent enzymes. Particularly preferred aro lipase, protease, amylasc, and mixtures theieof. Enzymes, if included, are typically at levels up to about 5%, preferably about 0.5-3%. Processing 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 the raw materials are mixed in the blender. The sodium salt of coco fatty alcohol sulfate and an alkaline inorganic salt (preferably sodium carbonate) are mixed in the presence of a polyphospliate builder. Then nlkyl benzene sulfonic ncid is reacted with the mixture to complete neutralization, the amount of alkaline inorganic salt sufficient to completely neutralize the acid, Once the neutralization reaction is completed, a non-liquid, thixotrophic binder such as coco nionocthanolamidc (CMEA) and other optional surfactants are added, followed by any additional optional components such as chelants. It is most preferable to use as raw materials, such materials which contain little moisture, The mixing can take from one minute to one hour, with the usual mixing time being from about two to twenty minutes, The bleach agent is added to the mixture and then mixed for an additional one to five minutes, It is usually added as one of the last ingredients, right before the perfume, if any, is added, The blender mix is charged to a surge tank. The product is conveyed from the surge tank to the null or refining plodder via a multi-worm conveyer. After nulling or preliminary plodding, the product is then conveyed to a double vacuum plodder, operating at high vacuum, e.g. 600 to 740 mm of mercury vacuum, so that entrapped air is removed. The product is extruded and cut to the desired bar length, and printed with the product brand name, Tho printed bar can bo cooled, for example in a cooliiip; tunnel, before H U wrapped, cased, and sent to storage. A preferred low moisture laundry har composition is made by the following method: The raw materials are first mixed in a blender. A dry form (flakes, noodles, needles, ground powder) and a high active neutralized paste form of sodium salt of coco fatty alcohol sulfate, sodium carbonate, and sodium tripolyphosphate is mixed for three minutes. The amount oif neutralized fatty alcohol sulfate paste with 23% to 35% moisture, contains an amount of water that will not translate to more than 2.5% moisture by weight in the final composition. A dose mixture of linear alkyl benzene sulfoulc acid and sulfurlo acid which have been pro-mixed for 1-1.5 minutes Is then added to the blender, being completely neutralized by the sodium carbonate in the seat of the blender. (The amount of sodium carbonate is at least an amount sufficient to neutralize the acids,) The materials are mixed for an additional 1-2 minutes after .dosing. Once the neutralization reaction is completed, a non-liquid, thixotrophic binder such as coco monocthanolamide (CMEA) and other optional surfactants are added, followed by any additional optional components such as chclants. It is most preferable to use as raw materials, such materials which contain little moisture, so as not to exceed 3% total moisture in the finished product. The mixing can take from one minuto to one hour, with the usual mixing time being from about five to ten minutes. As one of the last ingredients, the bleach agent is added to the mixture and then mixed for an additional one to five minutes. The blender mix is charged to a surge tank. The product is conveyed from the surge tank to the mill or refining plodder via a multl-woim conveyer, After milling or preliminary plodding, the product is then conveyed to a double vacuum plodder, operating at high vacuum, e,g, 600 to 740 mm of mercury vacuum, 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 of the invention are set forth hereinafter by way of illustration and are not intended to bo in any way limiting of the invention, BAR EXAMPLES The invention is illustrated by the following non-limiting examples. All parts and percentages herein arc by weight unless otherwise stated. Various bar compositions (Examples A through E) can be made using the method described above. (Table Removed) We claim: 1. A process for making low moisture laundry detergent bar, which comprises: (a) mixing a dry form and a neutralized paste form of a sodium salt of fatty alcohol sulfate in the presence of sodium carbonate, and a polyphosphate builder, (b) reacting alkyl benzene sulfonic acid with the mixture in (a), such that the acid is completely neutralized by the sodium carbonate, so as to obtain .5 to 60% wt. of surfactant; (c) adding 0.1% to 10% wt. of a non-liquid, thixotrophic binding agent; and optional components such as herein described, and (d) milling and plodding the mixture of (c) to form bars, wherein the total amount of moisture in the components added in Steps (a) to (c) is no more than about 3.5% of the moisture formed in (c). 2. A process for making low moisture laundry detergent bar as claimed in claim 1, which comprises: (a) mixing a dry form and a neutralized paste form of a sodium salt of fatty alcohol sulfate in the presence of sodium carbonate and sodium tripolyphosphate, (b) reacting alkyl benzene sulfonic acid with the mixture in (a), such that the acid is completely neutralized by the sodium carbonate. (c) adding a non-liquid, thixotrophic binding agent selected from the group consisting of C8-C18 fatty acid alkanol amide, polyethylene glycol and precipitated silica, and mixtures thereof, and optional components, and (d) milling and plodding the mixture of (c) to form bars, wherein the total amount of moisture in the components added in steps (a) through (c) is no more than about 3.5% of the moisture formed in (c). 3. A process for making a low moisture laundry detergent bar , substantially as hereinbefore described in any one of the Examples.

Documents:

1182-del-1997-abstract.pdf

1182-del-1997-claims.pdf

1182-del-1997-correspondence-others.pdf

1182-del-1997-correspondence-po.pdf

1182-del-1997-description (complete).pdf

1182-del-1997-form-1.pdf

1182-del-1997-form-19.pdf

1182-del-1997-form-2.pdf

1182-del-1997-form-3.pdf

1182-del-1997-form-4.pdf

1182-del-1997-form-6.pdf

1182-del-1997-gpa.pdf

1182-del-1997-petition-137.pdf

1182-del-1997-petition-138.pdf