EP0896052A1 - Detergent tablet - Google Patents

Detergent tablet Download PDF

Info

Publication number
EP0896052A1
EP0896052A1 EP97870116A EP97870116A EP0896052A1 EP 0896052 A1 EP0896052 A1 EP 0896052A1 EP 97870116 A EP97870116 A EP 97870116A EP 97870116 A EP97870116 A EP 97870116A EP 0896052 A1 EP0896052 A1 EP 0896052A1
Authority
EP
European Patent Office
Prior art keywords
tablet
tablets
kpa
detergent
core
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP97870116A
Other languages
German (de)
French (fr)
Inventor
Eric Tcheou
Steven René Martha Ongena
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Procter and Gamble Co
Original Assignee
Procter and Gamble Co
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Procter and Gamble Co filed Critical Procter and Gamble Co
Priority to EP97870116A priority Critical patent/EP0896052A1/en
Priority to DE69730599T priority patent/DE69730599T2/en
Priority to ES97870166T priority patent/ES2227661T3/en
Priority to AT97870166T priority patent/ATE275622T1/en
Priority to EP97870166A priority patent/EP0896053B1/en
Priority to BR9811880-3A priority patent/BR9811880A/en
Priority to CA002298832A priority patent/CA2298832C/en
Priority to AU86902/98A priority patent/AU740611B2/en
Priority to EP98938364A priority patent/EP1015546A1/en
Priority to US09/485,246 priority patent/US6677295B1/en
Priority to TR2000/00361T priority patent/TR200000361T2/en
Priority to CN98809639A priority patent/CN1272134A/en
Priority to JP2000506304A priority patent/JP2001512784A/en
Priority to KR1020007001266A priority patent/KR20010022671A/en
Priority to PCT/US1998/016254 priority patent/WO1999007819A1/en
Priority to MA25206A priority patent/MA24896A1/en
Priority to ZA987089A priority patent/ZA987089B/en
Priority to ARP980103921A priority patent/AR016810A1/en
Publication of EP0896052A1 publication Critical patent/EP0896052A1/en
Withdrawn legal-status Critical Current

Links

Classifications

    • CCHEMISTRY; METALLURGY
    • C11ANIMAL OR VEGETABLE OILS, FATS, FATTY SUBSTANCES OR WAXES; FATTY ACIDS THEREFROM; DETERGENTS; CANDLES
    • C11DDETERGENT COMPOSITIONS; USE OF SINGLE SUBSTANCES AS DETERGENTS; SOAP OR SOAP-MAKING; RESIN SOAPS; RECOVERY OF GLYCEROL
    • C11D3/00Other compounding ingredients of detergent compositions covered in group C11D1/00
    • C11D3/16Organic compounds
    • C11D3/37Polymers
    • C11D3/3703Macromolecular compounds obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds
    • C11D3/3707Polyethers, e.g. polyalkyleneoxides
    • CCHEMISTRY; METALLURGY
    • C11ANIMAL OR VEGETABLE OILS, FATS, FATTY SUBSTANCES OR WAXES; FATTY ACIDS THEREFROM; DETERGENTS; CANDLES
    • C11DDETERGENT COMPOSITIONS; USE OF SINGLE SUBSTANCES AS DETERGENTS; SOAP OR SOAP-MAKING; RESIN SOAPS; RECOVERY OF GLYCEROL
    • C11D17/00Detergent materials or soaps characterised by their shape or physical properties
    • C11D17/0047Detergents in the form of bars or tablets
    • C11D17/0065Solid detergents containing builders
    • C11D17/0073Tablets
    • C11D17/0082Coated tablets
    • CCHEMISTRY; METALLURGY
    • C11ANIMAL OR VEGETABLE OILS, FATS, FATTY SUBSTANCES OR WAXES; FATTY ACIDS THEREFROM; DETERGENTS; CANDLES
    • C11DDETERGENT COMPOSITIONS; USE OF SINGLE SUBSTANCES AS DETERGENTS; SOAP OR SOAP-MAKING; RESIN SOAPS; RECOVERY OF GLYCEROL
    • C11D3/00Other compounding ingredients of detergent compositions covered in group C11D1/00
    • C11D3/0005Other compounding ingredients characterised by their effect
    • C11D3/0052Gas evolving or heat producing compositions
    • CCHEMISTRY; METALLURGY
    • C11ANIMAL OR VEGETABLE OILS, FATS, FATTY SUBSTANCES OR WAXES; FATTY ACIDS THEREFROM; DETERGENTS; CANDLES
    • C11DDETERGENT COMPOSITIONS; USE OF SINGLE SUBSTANCES AS DETERGENTS; SOAP OR SOAP-MAKING; RESIN SOAPS; RECOVERY OF GLYCEROL
    • C11D3/00Other compounding ingredients of detergent compositions covered in group C11D1/00
    • C11D3/16Organic compounds
    • C11D3/20Organic compounds containing oxygen
    • C11D3/2075Carboxylic acids-salts thereof
    • C11D3/2079Monocarboxylic acids-salts thereof
    • CCHEMISTRY; METALLURGY
    • C11ANIMAL OR VEGETABLE OILS, FATS, FATTY SUBSTANCES OR WAXES; FATTY ACIDS THEREFROM; DETERGENTS; CANDLES
    • C11DDETERGENT COMPOSITIONS; USE OF SINGLE SUBSTANCES AS DETERGENTS; SOAP OR SOAP-MAKING; RESIN SOAPS; RECOVERY OF GLYCEROL
    • C11D1/00Detergent compositions based essentially on surface-active compounds; Use of these compounds as a detergent
    • C11D1/38Cationic compounds
    • C11D1/62Quaternary ammonium compounds

Definitions

  • the present invention relates to detergent tablets, especially those adapted for use in washing.
  • cleaning compositions in tablet form have often been proposed, these have not (with the exception of soap bars for personal washing) gained any substantial success, despite the several advantages of products in a unit dispensing form.
  • One of the reasons for this may be that detergent tablets usually dissolve slower than the constituent powders from which they are made, simply because the constituent powders are forced close together in the tablet, with comparatively little opportunity for water to permeate between them. This gives rise to the problem that slow dissolving tablets cause residues which may be visible throught the door of the washing machine during the wash cycle, or which stick to the fabrics at the end of the wash cycle, or both.
  • EP-A-0 716 144 published on 12th June 1996, discloses laundry detergent tablets with water-soluble coatings which may be organic polymers including acrylic/maleic co-polymer, polyethylene glycol, PVPVA, and sugar. It states that the tablets of the invention preferably have a diametral fracture stress of at least 5 kPa. The speed of disintegration of the tablets is measured by means of a test using a metal gauze.
  • the object of the present invention is to provide tablets with a core which is formed by compressing a particulate material, the particulate material comprising surfactant and detergent builder, the tablet being suitable for storing, shipping and handling without breakage.
  • a further object of the invention is to provide a tablet comprising a soft core which breaks up easily and rapidly, releasing the active ingredients into the wash solution and which completely disintegrates and disperses in alkaline or surfactant-rich solutions such as the wash liquor.
  • the object of the invention is achieved by providing a detergent tablet comprising a core and a coating, the core having a diametral fracture stress of less than 15 kPa, and the core comprising a non-gelling binder, wherein the coated detergent tablet has a diametral fracture stress of at least 20 kPa.
  • a detergent tablet having a diametral fracture stress of at least 20 kPa, the tablet giving less than 18g residue at the end of the washing machine cycle under stressed test, the stressed test consisting of three tablets, each tablet weighing 60g, being placed in the bottom of the drum of a Miele® W831 washing machine, 2.5 kg of mixed fabric load being placed in the drum on top of the tablets, and the machine being run using a "whites/colours" short cycle of 30°C.
  • Detergent tablets of the present invention can be prepared simply by mixing the solid ingredients together and compressing the mixture in a conventional tablet press as used, for example, in the pharmaceutical industry.
  • the principal ingredients in particular gelling surfactants, are used in particulate form.
  • Any liquid ingredients, for example the surfactant or suds suppressor, can be incorporated in a conventional manner into the solid particulate ingredients.
  • the ingredients such as builder and surfactant can be spray-dried in a conventional manner and then compacted at a suitable pressure.
  • the detergent tablets can be made in any size or shape and can, if desired, be surface treated before coating, according to the present invention.
  • a surfactant and a builder which normally provides a substantial part of the cleaning power of the tablet.
  • builder is intended to mean all materials which tend to remove calcium ion from solution, either by ion exchange, complexation, sequestration or precipitation.
  • the particulate material used for making the tablet of this invention can be made by any particulation or granulation process.
  • An example of such a process is spray drying (in a co-current or counter current spray drying tower) which typically gives low bulk densities 600g/l or lower.
  • Particulate materials of higher density can be prepared by granulation and densification in a high shear batch mixer/granulator or by a continuous granulation and densification process (e.g. using Lodige® CB and/or Lodige® KM mixers).
  • Other suitable processes include fluid bed processes, compaction processes (e.g. roll compaction), extrusion, as well as any particulate material made by any chemical process like flocculation, crystallisation sentering, etc.
  • Individual particles can also be any other particle, granule, sphere or grain.
  • the particulate materials may be mixed together by any conventional means. Batch is suitable in, for example, a concrete mixer, Nauta mixer, ribbon mixer or any other. Alternatively the mixing process may be carried out continuously by metering each component by weight on to a moving belt, and blending them in one or more drum(s) or mixer(s).
  • the non-gelling binder can be sprayed on to the mix of some, or all of, the particulate materials.
  • Other liquid ingredients may also be sprayed on to the mix of particulate materials either separately or premixed. For example perfume and slurries of optical brighteners may be sprayed.
  • a finely divided flow aid dustting agent such as zeolites, carbonates, silicas
  • the tablets may be manufactured by using any compacting process, such as tabletting, briquetting, or extrusion, preferably tabletting. Suitable equipment includes a standard single stroke or a rotary press (such as Courtoy®, Korch®, Manesty®, or Bonals®).
  • the tablets prepared according to this invention preferably have a diameter of between 40mm and 60mm, and a weight between 25 and 100 g.
  • the ratio of height to diameter (or width) of the tablets is preferably greater than 1:3, more preferably greater than 1:2.
  • the compaction pressure used for preparing these tablets need not exceed 5000 kN/m 2 , preferably not exceed 3000 kN/m 2 , and most preferably not exceed 1000 kN/m 2 .
  • Suitable non-gelling binders include synthetic organic polymers such as polyethylene glycols, polyvinylpyrrolidones, polyacrylates and water-soluble acrylate copolymers.
  • the handbook of Pharmaceutical Excipients second edition has the following binders classification: Acacia, Alginic Acid, Carbomer, Carboxymethylcellulose sodium, Dextrin, Ethylcellulose, Gelatin, Guar gum, Hydrogenated vegetable oil type I, Hydroxyethyl cellulose, Hydroxypropyl methylcellulose, Liquid glucose, Magnesium aluminum silicate, Maltodextrin, Methylcellulose, polymethacrylates, povidone, sodium alginate, starch and zein.
  • binders also have an active cleaning function in the laundry wash such as cationic polymers, i.e. ethoxylated hexamethylene diamine quaternary compounds, bishexamethylene triamines, or others such as pentaamines, ethoxylated polyethylene amines, maleic acrylic polymers.
  • cationic polymers i.e. ethoxylated hexamethylene diamine quaternary compounds, bishexamethylene triamines, or others such as pentaamines, ethoxylated polyethylene amines, maleic acrylic polymers.
  • the non-gelling binder materials are preferably sprayed on and hence have an appropriate melting point temperature below 70°C and preferably below 50°C so as not to damage or degrade the other active ingredients in the matrix.
  • Most preferred are non-aqueous liquid binders (i.e. not in aqueous solution) which may be sprayed in molten form.
  • they may also be solid binders incorporated into the matrix by dry addition but which have binding properties within the tablet.
  • the non-gelling binder materials are preferably used in an amount within the range from 0.1 to 15% of the composition, more preferably below 5% and especially if it is a non laundry active material below 2% by weight of the tablet.
  • gelling binders such as nonionic surfactants are avoided in their liquid or molten form.
  • Nonionic surfactants and other gelling binders are not excluded from the compositions, but it is preferred that they be processed into the detergent tablets as components of particulate materials, and not as liquids.
  • the tablets may then be coated so that the tablet does not absorb moisture, or absorbs moisture at only a very slow rate.
  • the coating is also strong so that moderate mechanical shocks to which the tablets are subjected during handling, packing and shipping result in no more than very low levels of breakage or attrition.
  • the coating is preferably brittle so that the tablet breaks up when subjected to stronger mechanical shock.
  • the coating material is dissolved under alkaline conditions, or is readily emulsified by surfactants. This contributes to avoiding the problem of visible residue in the window of a front-loading washing machine during the wash cycle, and also avoids deposition of undissolved particles or lumps of coating material on the laundry load.
  • Water solubility is measured following the test protocol of ASTM E1148-87 entitled, "Standard Test Method for Measurements of Aqueous Solubility".
  • Suitable coating materials are dicarboxylic acids.
  • Particularly suitable dicarboxylic acids are selected from the group consisting of oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, undecanedioic acid, dodecanedioic acid, tridecanedioic acid and mixtures thereof.
  • the coating material has a melting point preferably of from 40 °C to 200 °C.
  • the coating can be applied in a number of ways. Two preferred coating methods are a) coating with a molten material and b) coating with a solution of the material. In a), the coating material is applied at a temperature above its melting point, and solidifies on the tablet. In b), the coating is applied as a solution, the solvent being dried to leave a coherent coating.
  • the substantially insoluble material can be applied to the tablet by, for example, spraying or dipping. Normally when the molten material is sprayed on to the tablet, it will rapidly solidify to form a coherent coating. When tablets are dipped into the molten material and then removed, the rapid cooling again causes rapid solidification of the coating material.
  • substantially insoluble materials having a melting point below 40 °C are not sufficiently solid at ambient temperatures and it has been found that materials having a melting point above about 200 °C are not practicable to use.
  • the materials melt in the range from 60 °C to 160 °C, more preferably from 70 °C to 120 °C.
  • melting point is meant the temperature at which the material when heated slowly in, for example, a capillary tube becomes a clear liquid.
  • a coating of any desired thickness can be applied according to the present invention.
  • the coating forms from 1% to 10%, preferably from 1.5% to 5%, of the tablet weight.
  • the tablet coatings of the present invention are very hard and provide extra strength to the tablet.
  • the fracture of the coating in the wash is improved by adding a disintegrant in the coating.
  • This disintegrant will swell once in contact with water and break the coating in small pieces. This will improve the dissolution of the coating in the wash solution.
  • the disintegrant is suspended in the coating melt at a level of up to 30%, preferably between 5% and 20%, most preferably between 5 and 10% by weight. Possible disintegrants are described in Handbook of Pharmaceutical Excipients (1986).
  • Suitable disintegrants include starch: natural, modified or pregelatinized starch, sodium starch gluconate; gum: agar gum, guar gum, locust bean gum, karaya gum, pectin gum, tragacanth gum; croscarmylose Sodium, crospovidone, cellulose, carboxymethyl cellulose, algenic acid and its salts including sodium alginate, silicone dioxide, clay, polyvinylpyrrolidone, soy polysacharides, ion exchange resins and mixtures thereof.
  • the used compaction force will be adjusted to not affect the strength (Diametral Fracture Stress), and the disintegration time in the washing machine.
  • This process may be used to prepare homogenous or layered tablets of any size or shape.
  • Diametrical Fracture Stress is a way to express the strength of a tablet, it is determined by the following equation:
  • F is the maximum force (Newton) to cause tensile failure (fracture) measured by a VK 200 tablet hardness tester supplied by Van Kell industries, Inc.
  • D is the diameter of the tablet, and t the thickness of the tablet.
  • Methods Pharmaceutical Dosage Forms Tablets Volume 2 Page 213 to 217).
  • a tablet having a diametral fracture stress of less than 20 kPa is considered to be fragile and is likely to result in some broken tablets being delivered to the consumer.
  • a diametral fracture stress of at least 25 kPa is preferred.
  • the rate of disintegration of a detergent tablet can be determined in two ways:
  • residues are spun out of the wash load, and the residues which are stuck at the front window porthole are collected and the total is weighed.
  • the level of residues is determined by repeating the procedure 10 times and an average residue level is calculated based on the ten individual measurements. In this stressed test a residue of 18g (i.e. corresponding to 10% of the starting tablet weight) is considered to be acceptable. A residue of less than 10g is preferred, and less than 5g is more preferred.
  • the tablets further comprises an effervescent.
  • Effervescency as defined herein means the evolution of bubbles of gas from a liquid, as the result of a chemical reaction between a soluble acid source and an alkali metal carbonate, to produce carbon dioxide gas, i.e. C 6 H 8 O 7 + 3NaHCO 3 ⁇ Na 3 C 6 H 5 O 7 + 3CO 2 ⁇ + 3H 2 O
  • An effervescent may be added to the tablet mix in addition to the detergent ingredients.
  • the addition of this effervescent to the detergent tablet improves the disintegration time of the tablet.
  • the amount will preferably be between 5 and 20 % and most preferably between 10 and 20% by weight of the tablet.
  • the effervescent should be added as an agglomerate of the different particles or as a compact, and not as separated particles. Due to the gas created by the effervescency in the tablet, the tablet can have a higher D.F.S. and still have the same disintegration time as a tablet without effervescency. When the D.F.S. of the tablet with effervescency is kept the same as a tablet without, the disintegration of the tablet with effervescency will be faster.
  • Nonlimiting examples of surfactants useful herein typically at levels from about 1% to about 55%, by weight include the conventional C 11- C 18 alkyl benzene sulfonates ("LAS") and primary, branched-chain and random C 10- C 20 alkyl sulfates (“AS”), the C 10- C 18 secondary (2,3) alkyl sulfates of the formula CH 3 (CH 2 ) x (CHOSO 3- M + ) CH 3 and CH 3 (CH 2 ) y (CHOSO 3- M + ) CH 2 CH 3 where x and (y + 1) are integers of at least about 7, preferably at least about 9, and M is a water-solubilizing cation, especially sodium, unsaturated sulfates such as oleyl sulfate, the C 10- C 18 alkyl alkoxy sulfates (“AE X S”; especially EO 1-7 ethoxy sulfates), C 10- C 18 alkyl alkoxy carboxylates (especially the EO 1-5
  • the conventional nonionic and amphoteric surfactants such as the C 12- C 18 alkyl ethoxylates ("AE") including the so-called narrow peaked alkyl ethoxylates and C 6 -C 12 alkyl phenol alkoxylates (especially ethoxylates and mixed ethoxy/propoxy), C 12- C 18 betaines and sulfobetaines ("sultaines"), C 10- C 18 amine oxides, and the like, can also be included in the overall compositions.
  • the C 10 -C 18 N-alkyl polyhydroxy fatty acid amides can also be used. Typical examples include the C 12 -C 18 N-methylglucamides. See WO 9,206,154.
  • sugar-derived surfactants include the N-alkoxy polyhydroxy fatty acid amides, such as C 10 -C 18 N-(3-methoxypropyl) glucamide.
  • the N-propyl through N-hexyl C 12 -C 18 glucamides can be used for low sudsing.
  • C 10 -C 20 conventional soaps may also be used. If high sudsing is desired, the branched-chain C 10 -C 16 soaps may be used. Mixtures of anionic and nonionic surfactants are especially useful. Other conventional useful surfactants are listed in standard texts.
  • Detergent builders can optionally be included in the compositions herein to assist in controlling mineral hardness.
  • Inorganic as well as organic builders can be used. Builders are typically used in fabric laundering compositions to assist in the removal of particulate soils. The level of builder can vary widely depending upon the end use of the composition.
  • Inorganic or P-containing detergent builders include, but are not limited to, the alkali metal, ammonium and alkanolammonium salts of polyphosphates (exemplified by the tripolyphosphates, pyrophosphates, and glassy polymeric meta-phosphates), phosphonates, phytic acid, silicates, carbonates (including bicarbonates and sesquicarbonates), sulphates, and aluminosilicates.
  • non-phosphate builders are required in some locales.
  • the compositions herein function surprisingly well even in the presence of the so-called "weak” builders (as compared with phosphates) such as citrate, or in the so-called "underbuilt” situation that may occur with zeolite or layered silicate builders.
  • silicate builders are the alkali metal silicates, particularly those having a SiO 2 :Na 2 O ratio in the range 1.6:1 to 3.2:1 and layered silicates, such as the layered sodium silicates described in U.S. Patent 4,664,839, issued May 12, 1987 to H. P. Rieck.
  • NaSKS-6 is the trademark for a crystalline layered silicate marketed by Hoechst (commonly abbreviated herein as "SKS-6"). Unlike zeolite builders, the Na SKS-6 silicate builder does not contain aluminum. NaSKS-6 has the delta-Na 2 SiO 5 morphology form of layered silicate. It can be prepared by methods such as those described in German DE-A-3,417,649 and DE-A-3,742,043.
  • SKS-6 is a highly preferred layered silicate for use herein, but other such layered silicates, such as those having the general formula NaMSi x O 2x+1 ⁇ yH 2 O wherein M is sodium or hydrogen, x is a number from 1.9 to 4, preferably 2, and y is a number from 0 to 20, preferably 0 can be used herein.
  • Various other layered silicates from Hoechst include NaSKS-5, NaSKS-7 and NaSKS-11, as the alpha, beta and gamma forms. As noted above, the delta-Na 2 SiO 5 (NaSKS-6 form) is most preferred for use herein.
  • silicates may also be useful such as for example magnesium silicate, which can serve as a crispening agent in granular formulations, as a stabilizing agent for oxygen bleaches, and as a component of suds control systems.
  • carbonate builders are the alkaline earth and alkali metal carbonates as disclosed in German Patent Application No. 2,321,001 published on November 15, 1973.
  • Aluminosilicate builders are useful in the present invention. Aluminosilicate builders are of great importance in most currently marketed heavy duty granular detergent compositions, and can also be a significant builder ingredient in liquid detergent formulations.
  • Aluminosilicate builders include those having the empirical formula: M z (zAlO 2 ) y ] ⁇ xH 2 O wherein z and y are integers of at least 6, the molar ratio of z to y is in the range from 1.0 to about 0.5, and x is an integer from about 15 to about 264.
  • Useful aluminosilicate ion exchange materials are commercially available. These aluminosilicates can be crystalline or amorphous in structure and can be naturally-occurring aluminosilicates or synthetically derived.
  • a method for producing aluminosilicate ion exchange materials is disclosed in U.S. Patent 3,985,669, Krummel, et al, issued October 12, 1976.
  • the aluminosilicate has a particle size of about 0.1-10 microns in diameter.
  • Organic detergent builders suitable for the purposes of the present invention include, but are not restricted to, a wide variety of polycarboxylate compounds.
  • polycarboxylate refers to compounds having a plurality of carboxylate groups, preferably at least 3 carboxylates.
  • Polycarboxylate builder can generally be added to the composition in acid form, but can also be added in the form of a neutralized salt. When utilized in salt form, alkali metals, such as sodium, potassium, and lithium, or alkanolammonium salts are preferred. Included among the polycarboxylate builders are a variety of categories of useful materials.
  • polycarboxylate builders encompasses the ether polycarboxylates, including oxydisuccinate, as disclosed in Berg, U.S. Patent 3,128,287, issued April 7, 1964, and Lamberti et al, U.S. Patent 3,635,830, issued January 18, 1972. See also "TMS/TDS" builders of U.S. Patent 4,663,071, issued to Bush et al, on May 5, 1987.
  • Suitable ether polycarboxylates also include cyclic compounds, particularly alicyclic compounds, such as those described in U.S. Patents 3,923,679; 3,835,163; 4,158,635; 4,120,874 and 4,102,903.
  • ether hydroxypolycarboxylates copolymers of maleic anhydride with ethylene or vinyl methyl ether, 1, 3, 5-trihydroxy benzene-2, 4, 6-trisulphonic acid, and carboxymethyloxysuccinic acid
  • various alkali metal, ammonium and substituted ammonium salts of polyacetic acids such as ethylenediamine tetraacetic acid and nitrilotriacetic acid
  • polycarboxylates such as mellitic acid, succinic acid, oxydisuccinic acid, polymaleic acid, benzene 1,3,5-tricarboxylic acid, carboxymethyloxysuccinic acid, and soluble salts thereof.
  • Citrate builders e.g., citric acid and soluble salts thereof (particularly sodium salt), are polycarboxylate builders of particular importance for heavy duty liquid detergent formulations due to their availability from renewable resources and their biodegradability. Citrates can also be used in granular compositions, especially in combination with zeolite and/or layered silicate builders. Oxydisuccinates are also especially useful in such compositions and combinations. Also suitable in the detergent compositions of the present invention are the 3,3-dicarboxy-4-oxa-1,6-hexanedioates and the related compounds disclosed in U.S. Patent 4,566,984, Bush, issued January 28, 1986.
  • succinic acid builders include the C 5 -C 20 alkyl and alkenyl succinic acids and salts thereof.
  • a particularly preferred compound of this type is dodecenylsuccinic acid.
  • succinate builders include: laurylsuccinate, myristylsuccinate, palmitylsuccinate, 2-dodecenylsuccinate (preferred), 2-pentadecenylsuccinate, and the like.
  • Laurylsuccinates are the preferred builders of this group, and are described in European Patent Application 86200690.5/0,200,263, published November 5, 1986.
  • Other suitable polycarboxylates are disclosed in U.S. Patent 4,144,226, Crutchfield et al, issued March 13, 1979 and in U.S. Patent 3,308,067, Diehl, issued March 7, 1967. See also Diehl U.S. Patent 3,723,322.
  • Fatty acids e.g., C 12 -C 18 monocarboxylic acids
  • the aforesaid builders especially citrate and/or the succinate builders, to provide additional builder activity.
  • Such use of fatty acids will generally result in a diminution of sudsing, which should be taken into account by the formulator.
  • the various alkali metal phosphates such as the well-known sodium tripolyphosphates, sodium pyrophosphate and sodium orthophosphate can be used.
  • Phosphonate builders such as ethane-1-hydroxy-1,1-diphosphonate and other known phosphonates (see, for example, U.S. Patents 3,159,581; 3,213,030; 3,422,021; 3,400,148 and 3,422,137) can also be used.
  • the detergent compositions herein may optionally contain bleaching agents or bleaching compositions containing a bleaching agent and one or more bleach activators.
  • bleaching agents will typically be at levels of from about 1% to about 30%, more typically from about 5% to about 20%, of the detergent composition, especially for fabric laundering.
  • the amount of bleach activators will typically be from about 0.1% to about 60%, more typically from about 0.5% to about 40% of the bleaching composition comprising the bleaching agent-plus-bleach activator.
  • the bleaching agents used herein can be any of the bleaching agents useful for detergent compositions in textile cleaning, hard surface cleaning, or other cleaning purposes that are now known or become known. These include oxygen bleaches as well as other bleaching agents.
  • Perborate beaches e.g., sodium perborate (e.g., mono- or tetra-hydrate) can be used herein.
  • Another category of bleaching agent that can be used without restriction encompasses percarboxylic acid bleaching 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 bleaching agents are disclosed in U.S. Patent 4,483,781, Hartman, issued November 20, 1984, U.S.
  • Highly preferred bleaching agents also include 6-nonylamino-6-oxoperoxycaproic acid as described in U.S. Patent 4,634,551, issued January 6, 1987 to Burns et al.
  • Peroxygen bleaching agents can also be used. Suitable peroxygen bleaching compounds include sodium carbonate peroxyhydrate and equivalent "percarbonate" beaches, sodium pyrophosphate peroxyhydrate, urea peroxyhydrate, and sodium peroxide.
  • Persulfate bleach (e.g., OXONE, manufactured commercially by DuPont) can also be used.
  • a preferred 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.
  • 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. Mixtures of bleaching agents can also be used.
  • Peroxygen bleaching 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.
  • bleach activators 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.
  • NOBS nonanoyloxybenzene sulfonate
  • TAED tetraacetyl ethylene diamine
  • amido-derived bleach activators are those of the formulae: R 1 N(R 5 )C(O)R 2 C(O)L or R 1 C(O)N(R 5 )R 2 C(O)L wherein R 1 is an alkyl group containing from about 6 to about 12 carbon atoms, R 2 is an alkylene containing from 1 to about 6 carbon atoms, R 5 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.
  • 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, incorporated herein by reference.
  • 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, incorporated herein by reference.
  • 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 of the formulae: wherein R 6 is H or an alkyl, aryl, alkoxyaryl, or alkaryl group containing from 1 to about 12 carbon atoms.
  • 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, incorporated herein by reference, which discloses acyl caprolactams, including benzoyl caprolactam, adsorbed into sodium perborate.
  • Bleaching agents other than oxygen bleaching agents are also known in the art and can be utilized herein.
  • One type of non-oxygen bleaching agent of particular interest includes photoactivated bleaching 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 beaches, especially sulfonate zinc phthalocyanine.
  • the bleaching compounds can be catalyzed by means of a manganese compound.
  • 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.
  • Preferred examples of these catalysts include Mn IV 2 (u-O) 3 (1,4,7-trimethyl-1,4,7-triazacyclononane) 2 (PF 6 ) 2 , Mn III 2 (u-O) 1 (u-OAc) 2 (1,4,7-trimethyl-1,4,7-triazacyclononane) 2- (ClO 4 ) 2 , Mn IV 4 (u-O) 6 (1,4,7-triazacyclononane) 4 (ClO 4 ) 4 , Mn III Mn IV 4 (u-O) 1 (u-OAc) 2- (1,4,7-trimethyl-1,4,7-triazacyclononane) 2 (ClO 4 ) 3 , Mn IV (1,4,7-trimethyl-1,4,7-triazacyclononane)-(OCH 3 ) 3 (PF 6 ), and mixtures thereof.
  • 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.
  • 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.
  • Enzymes can be included in the formulations herein for a wide variety of fabric laundering purposes, including removal of protein-based, carbohydrate-based, or triglyceride-based stains, for example, and for the prevention of refugee dye transfer, and for fabric restoration.
  • the enzymes to be incorporated include proteases, amylases, lipases, cellulases, and peroxidases, as well as mixtures thereof.
  • 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.
  • bacterial or fungal enzymes are preferred, such as bacterial amylases and proteases, and fungal cellulases.
  • Enzymes are normally incorporated at levels sufficient to provide up to about 5 mg by weight, more typically about 0.01 mg to about 3 mg, of active enzyme per gram of the composition.
  • the compositions herein will typically comprise from about 0.001% to about 5%, preferably 0.01%-1 % by weight of a commercial enzyme preparation.
  • Protease enzymes are usually present in such commercial preparations at levels sufficient to provide from 0.005 to 0.1 Anson units (AU) of activity per gram of composition.
  • AU Anson units
  • proteases are the subtilisins which are obtained from particular strains of B. subtilis and B. licheniforms. Another suitable protease is obtained from a strain of Bacillus, having maximum activity throughout the pH range of 8-12, developed and sold by Novo Industries A/S under the registered trade name ESPERASE. The preparation of this enzyme and analogous enzymes is described in British Patent Specification No. 1,243,784 of Novo.
  • protealytic enzymes suitable for removing protein-based stains that are commercially available include those sold under the tradenames ALCALASE and SAVINASE by Novo Industries A/S (Denmark) and MAXATASE by International Bio-Synthetics, Inc. (The Netherlands).
  • proteases include Protease A (see European Patent Application 130,756, published January 9, 1985) and Protease B (see European Patent Application Serial No. 87303761.8, filed April 28, 1987, and European Patent Application 130,756, Bott et al, published January 9, 1985).
  • Amylases include, for example, ⁇ -amylases described in British Patent Specification No. 1,296,839 (Novo), RAPIDASE, International Bio-Synthetics, Inc. and TERMAMYL, Novo Industries.
  • the cellulase 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 DSM1800 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.
  • 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 British Patent 1,372,034. See also lipases in Japanese Patent Application 53,20487, laid open to public inspection on February 24, 1978. This lipase is available from Amano Pharmaceutical Co. Ltd., Nagoya, Japan, under the trade name Lipase P "Amano,” hereinafter referred to as "Amano-P.” Other commercial lipases include Amano-CES, lipases ex Chromobacter viscosum, e.g. Chromobacter viscosum var.
  • lipolyticum NRRLB 3673 commercially available from Toyo Jozo Co., Tagata, Japan; and further Chromobacter viscosum lipases from U.S. Biochemical Corp., U.S.A. and Disoynth Co., The Netherlands, and lipases ex Pseudomonas gladioli.
  • the LIPOLASE enzyme derived from Humicola lanuginosa and commercially available from Novo is a preferred lipase for use herein.
  • 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.
  • 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 International Application WO 89/099813, published October 19, 1989, by O. Kirk, assigned to Novo Industries A/S.
  • a wide range of enzyme materials and means for their incorporation 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.
  • compositions which are comonly used in detergent compositions and which may be incorpoated into the detergent tablets of the present invention include chelating agents, soil release agents, soil antiredeposition agents, dispersing agents, brighteners, suds suppressors, fabric softeners, dye transfer inhibition agents and perfumes.
  • a detergent base powder of Composition 1 is prepared by the following steps:
  • Nonionic AE7/PEG4000 mixture is sprayed on the sodium perborate in a mixing drum.
  • zeolite is used to dust the perborate impregnated with nonionic to eliminate its potential to bind the other powders;
  • Ethoxylated hexamethylenediamine quat (the non-gelling binder) is sprayed on to the layered silicate, the bleach activator agglomerates and the carbonate; the contents of these two mixing drums are then mixed together with the remaining particulate materials of Composition 1 to form a homogeneous particulate.
  • composition 1 80 parts of the Composition 1 are then mixed in a mixing drum with 15 parts of sodium acetate and 5 parts of an effervescent mix consisting of 54.5% sodium bicarbonate and 45.5% citric acid.
  • Tablets are then made by introducing 55g of the mixture into a circular mold (diameter 54mm) and compressed to give tablets of 21 mm height and a density of 1.1 g/cc.
  • the diametral fracture stress is 6 kPa.
  • the tablets are then dipped into a coating bath containing 90 parts of dodecanedioic acid mixed with 10 parts of Nymcel z6b16 heated to 140°C.
  • the tablets are left in the bath for just long enough for 5g of coating to be applied, after which the tablets are removed and left to cool at 25°C for 24 hours.
  • the diametral fracture stress is increased by the coating to greater than 20 kPa.
  • a detergent base powder of Composition 1 is prepared by the following steps:

Landscapes

  • Chemical & Material Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Oil, Petroleum & Natural Gas (AREA)
  • Wood Science & Technology (AREA)
  • Organic Chemistry (AREA)
  • Health & Medical Sciences (AREA)
  • Emergency Medicine (AREA)
  • Detergent Compositions (AREA)
  • Main Body Construction Of Washing Machines And Laundry Dryers (AREA)

Abstract

The present invention relates a detergent tablet comprising a core and a coating, the core having a diametral fracture stress of less than 15 kPa, and the core comprising a non-gelling binder, wherein the coated detergent tablet has a diametral fracture stress of at least 20 kPa.
In a further aspect of the invention there is provided a detergent tablet having a diametral fracture stress of at least 20 kPa, the tablet giving less than 18g residue at the end of the washing machine cycle under stressed test, the stressed test consisting of three tablets, each tablet weighting 60g, being placed in the bottom of the drum of a washing machine, 2.5 kg of mixed fabric load being placed in the drum on top of the tablets, and the machine being run using a "whites/colours" short cycle of 30°C.

Description

  • The present invention relates to detergent tablets, especially those adapted for use in washing.
  • Although cleaning compositions in tablet form have often been proposed, these have not (with the exception of soap bars for personal washing) gained any substantial success, despite the several advantages of products in a unit dispensing form. One of the reasons for this may be that detergent tablets usually dissolve slower than the constituent powders from which they are made, simply because the constituent powders are forced close together in the tablet, with comparatively little opportunity for water to permeate between them. This gives rise to the problem that slow dissolving tablets cause residues which may be visible throught the door of the washing machine during the wash cycle, or which stick to the fabrics at the end of the wash cycle, or both.
  • EP-A-0 716 144, published on 12th June 1996, discloses laundry detergent tablets with water-soluble coatings which may be organic polymers including acrylic/maleic co-polymer, polyethylene glycol, PVPVA, and sugar. It states that the tablets of the invention preferably have a diametral fracture stress of at least 5 kPa. The speed of disintegration of the tablets is measured by means of a test using a metal gauze.
  • However, in certain front loading washing machines, problems of tablet residues appearing visibly at the window of the washing machine have still been encountered.
  • The object of the present invention is to provide tablets with a core which is formed by compressing a particulate material, the particulate material comprising surfactant and detergent builder, the tablet being suitable for storing, shipping and handling without breakage.
  • A further object of the invention is to provide a tablet comprising a soft core which breaks up easily and rapidly, releasing the active ingredients into the wash solution and which completely disintegrates and disperses in alkaline or surfactant-rich solutions such as the wash liquor.
  • Summary of the Invention
  • The object of the invention is achieved by providing a detergent tablet comprising a core and a coating, the core having a diametral fracture stress of less than 15 kPa, and the core comprising a non-gelling binder, wherein the coated detergent tablet has a diametral fracture stress of at least 20 kPa.
  • In a further aspect of the invention there is provided a detergent tablet having a diametral fracture stress of at least 20 kPa, the tablet giving less than 18g residue at the end of the washing machine cycle under stressed test, the stressed test consisting of three tablets, each tablet weighing 60g, being placed in the bottom of the drum of a Miele® W831 washing machine, 2.5 kg of mixed fabric load being placed in the drum on top of the tablets, and the machine being run using a "whites/colours" short cycle of 30°C.
  • Detailed Description of the Invention
  • Detergent tablets of the present invention can be prepared simply by mixing the solid ingredients together and compressing the mixture in a conventional tablet press as used, for example, in the pharmaceutical industry. Preferably the principal ingredients, in particular gelling surfactants, are used in particulate form. Any liquid ingredients, for example the surfactant or suds suppressor, can be incorporated in a conventional manner into the solid particulate ingredients.
  • In particular for laundry tablets, the ingredients such as builder and surfactant can be spray-dried in a conventional manner and then compacted at a suitable pressure.
    The detergent tablets can be made in any size or shape and can, if desired, be surface treated before coating, according to the present invention. In the core of the tablet is included a surfactant and a builder which normally provides a substantial part of the cleaning power of the tablet. The term "builder" is intended to mean all materials which tend to remove calcium ion from solution, either by ion exchange, complexation, sequestration or precipitation.
  • The particulate material used for making the tablet of this invention can be made by any particulation or granulation process. An example of such a process is spray drying (in a co-current or counter current spray drying tower) which typically gives low bulk densities 600g/l or lower. Particulate materials of higher density can be prepared by granulation and densification in a high shear batch mixer/granulator or by a continuous granulation and densification process (e.g. using Lodige® CB and/or Lodige® KM mixers). Other suitable processes include fluid bed processes, compaction processes (e.g. roll compaction), extrusion, as well as any particulate material made by any chemical process like flocculation, crystallisation sentering, etc. Individual particles can also be any other particle, granule, sphere or grain.
  • The particulate materials may be mixed together by any conventional means. Batch is suitable in, for example, a concrete mixer, Nauta mixer, ribbon mixer or any other. Alternatively the mixing process may be carried out continuously by metering each component by weight on to a moving belt, and blending them in one or more drum(s) or mixer(s). The non-gelling binder can be sprayed on to the mix of some, or all of, the particulate materials. Other liquid ingredients may also be sprayed on to the mix of particulate materials either separately or premixed. For example perfume and slurries of optical brighteners may be sprayed. A finely divided flow aid (dusting agent such as zeolites, carbonates, silicas) can be added to the particulate materials after spraying the binder, preferably towards the end of the process, to make the mix less sticky.
  • The tablets may be manufactured by using any compacting process, such as tabletting, briquetting, or extrusion, preferably tabletting. Suitable equipment includes a standard single stroke or a rotary press (such as Courtoy®, Korch®, Manesty®, or Bonals®). The tablets prepared according to this invention preferably have a diameter of between 40mm and 60mm, and a weight between 25 and 100 g. The ratio of height to diameter (or width) of the tablets is preferably greater than 1:3, more preferably greater than 1:2. The compaction pressure used for preparing these tablets need not exceed 5000 kN/m2, preferably not exceed 3000 kN/m2, and most preferably not exceed 1000 kN/m2.
  • Suitable non-gelling binders include synthetic organic polymers such as polyethylene glycols, polyvinylpyrrolidones, polyacrylates and water-soluble acrylate copolymers. The handbook of Pharmaceutical Excipients second edition, has the following binders classification: Acacia, Alginic Acid, Carbomer, Carboxymethylcellulose sodium, Dextrin, Ethylcellulose, Gelatin, Guar gum, Hydrogenated vegetable oil type I, Hydroxyethyl cellulose, Hydroxypropyl methylcellulose, Liquid glucose, Magnesium aluminum silicate, Maltodextrin, Methylcellulose, polymethacrylates, povidone, sodium alginate, starch and zein. Most preferable binders also have an active cleaning function in the laundry wash such as cationic polymers, i.e. ethoxylated hexamethylene diamine quaternary compounds, bishexamethylene triamines, or others such as pentaamines, ethoxylated polyethylene amines, maleic acrylic polymers.
  • The non-gelling binder materials are preferably sprayed on and hence have an appropriate melting point temperature below 70°C and preferably below 50°C so as not to damage or degrade the other active ingredients in the matrix. Most preferred are non-aqueous liquid binders (i.e. not in aqueous solution) which may be sprayed in molten form. However, they may also be solid binders incorporated into the matrix by dry addition but which have binding properties within the tablet.
  • The non-gelling binder materials are preferably used in an amount within the range from 0.1 to 15% of the composition, more preferably below 5% and especially if it is a non laundry active material below 2% by weight of the tablet.
  • It is preferred that gelling binders, such as nonionic surfactants are avoided in their liquid or molten form. Nonionic surfactants and other gelling binders are not excluded from the compositions, but it is preferred that they be processed into the detergent tablets as components of particulate materials, and not as liquids.
  • In one embodiment of the present invention, the tablets may then be coated so that the tablet does not absorb moisture, or absorbs moisture at only a very slow rate. The coating is also strong so that moderate mechanical shocks to which the tablets are subjected during handling, packing and shipping result in no more than very low levels of breakage or attrition. Finally the coating is preferably brittle so that the tablet breaks up when subjected to stronger mechanical shock. Furthermore it is advantageous if the coating material is dissolved under alkaline conditions, or is readily emulsified by surfactants. This contributes to avoiding the problem of visible residue in the window of a front-loading washing machine during the wash cycle, and also avoids deposition of undissolved particles or lumps of coating material on the laundry load.
  • Water solubility is measured following the test protocol of ASTM E1148-87 entitled, "Standard Test Method for Measurements of Aqueous Solubility".
  • Suitable coating materials are dicarboxylic acids. Particularly suitable dicarboxylic acids are selected from the group consisting of oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, undecanedioic acid, dodecanedioic acid, tridecanedioic acid and mixtures thereof.
  • The coating material has a melting point preferably of from 40 °C to 200 °C. The coating can be applied in a number of ways. Two preferred coating methods are a) coating with a molten material and b) coating with a solution of the material.
    In a), the coating material is applied at a temperature above its melting point, and solidifies on the tablet. In b), the coating is applied as a solution, the solvent being dried to leave a coherent coating. The substantially insoluble material can be applied to the tablet by, for example, spraying or dipping. Normally when the molten material is sprayed on to the tablet, it will rapidly solidify to form a coherent coating. When tablets are dipped into the molten material and then removed, the rapid cooling again causes rapid solidification of the coating material. Clearly substantially insoluble materials having a melting point below 40 °C are not sufficiently solid at ambient temperatures and it has been found that materials having a melting point above about 200 °C are not practicable to use. Preferably, the materials melt in the range from 60 °C to 160 °C, more preferably from 70 °C to 120 °C. By "melting point" is meant the temperature at which the material when heated slowly in, for example, a capillary tube becomes a clear liquid.
  • A coating of any desired thickness can be applied according to the present invention. For most purposes, the coating forms from 1% to 10%, preferably from 1.5% to 5%, of the tablet weight.
  • The tablet coatings of the present invention are very hard and provide extra strength to the tablet.
  • In a preferred embodiment of the present invention the fracture of the coating in the wash is improved by adding a disintegrant in the coating. This disintegrant will swell once in contact with water and break the coating in small pieces. This will improve the dissolution of the coating in the wash solution. The disintegrant is suspended in the coating melt at a level of up to 30%, preferably between 5% and 20%, most preferably between 5 and 10% by weight. Possible disintegrants are described in Handbook of Pharmaceutical Excipients (1986). Examples of suitable disintegrants include starch: natural, modified or pregelatinized starch, sodium starch gluconate; gum: agar gum, guar gum, locust bean gum, karaya gum, pectin gum, tragacanth gum; croscarmylose Sodium, crospovidone, cellulose, carboxymethyl cellulose, algenic acid and its salts including sodium alginate, silicone dioxide, clay, polyvinylpyrrolidone, soy polysacharides, ion exchange resins and mixtures thereof.
  • Depending on the composition of the starting material, and the shape of the tablets, the used compaction force will be adjusted to not affect the strength (Diametral Fracture Stress), and the disintegration time in the washing machine. This process may be used to prepare homogenous or layered tablets of any size or shape.
  • Diametrical Fracture Stress (DFS) is a way to express the strength of a tablet, it is determined by the following equation:
    Figure 00080001
  • Where F is the maximum force (Newton) to cause tensile failure (fracture) measured by a VK 200 tablet hardness tester supplied by Van Kell industries, Inc. D is the diameter of the tablet, and t the thickness of the tablet. (Method Pharmaceutical Dosage Forms: Tablets Volume 2 Page 213 to 217). A tablet having a diametral fracture stress of less than 20 kPa is considered to be fragile and is likely to result in some broken tablets being delivered to the consumer. A diametral fracture stress of at least 25 kPa is preferred.
  • The rate of disintegration of a detergent tablet can be determined in two ways:
  • a) In a "VAN KEL" Friabilator with "Vankel Type" drums.
    • Put 2 tablets with a known weight and D.F.S in the Friabilator drum.
    • Rotate the drum for 20 rotations.
    • Collect all product and remaining tablet pieces from the Friabilator drum, and screen it on 5 mm, and through 1.7 mm
    • Express as % residue on 5 mm and through 1.7 mm.
    • The higher the % of material through 1.7 mm the better the disintegration.
  • b) In a washing machine according to the following method
    Three tablets, nominally 60 grams each, are weighed, and then placed in at the bottom of the wash drum of a front loading Miele® W831 washing machine. The machine is then filled with a 2.5kg clean ballast which comprises 8 terry towels, 5 T-shirts, and 5 kitchen towels. The washing machine wash temperature is set to 30°C, the water supplied to the washing machine is set to a hardness of 21 grains per gram, and the wash cycle set to the wash program "Whites/Colors, short cycle".
  • At the end of the full cycle the residues are spun out of the wash load, and the residues which are stuck at the front window porthole are collected and the total is weighed. The level of residues is determined by repeating the procedure 10 times and an average residue level is calculated based on the ten individual measurements. In this stressed test a residue of 18g (i.e. corresponding to 10% of the starting tablet weight) is considered to be acceptable. A residue of less than 10g is preferred, and less than 5g is more preferred.
  • In a more stressed test the washing machine is stopped after ten minutes of the wash cycle and the residues are collected and weighed.
  • In another preferred embodiment of the present invention the tablets further comprises an effervescent.
    Effervescency as defined herein means the evolution of bubbles of gas from a liquid, as the result of a chemical reaction between a soluble acid source and an alkali metal carbonate, to produce carbon dioxide gas, i.e. C6H8O7 + 3NaHCO3 → Na3C6H5O7 + 3CO2 ↑ + 3H2O
  • Further examples of acid and carbonate sources and other effervescent systems may be found in: (Pharmaceutical Dosage Forms : Tablets Volume 1 Page 287 to 291)
  • An effervescent may be added to the tablet mix in addition to the detergent ingredients. The addition of this effervescent to the detergent tablet improves the disintegration time of the tablet. The amount will preferably be between 5 and 20 % and most preferably between 10 and 20% by weight of the tablet. Preferably the effervescent should be added as an agglomerate of the different particles or as a compact, and not as separated particles.
    Due to the gas created by the effervescency in the tablet, the tablet can have a higher D.F.S. and still have the same disintegration time as a tablet without effervescency. When the D.F.S. of the tablet with effervescency is kept the same as a tablet without, the disintegration of the tablet with effervescency will be faster.
  • Detersive surfactants
  • Nonlimiting examples of surfactants useful herein typically at levels from about 1% to about 55%, by weight, include the conventional C11-C18 alkyl benzene sulfonates ("LAS") and primary, branched-chain and random C10-C20 alkyl sulfates ("AS"), the C10-C18 secondary (2,3) alkyl sulfates of the formula CH3(CH2)x(CHOSO3-M+) CH3 and CH3 (CH2)y(CHOSO3-M+) CH2CH3 where x and (y + 1) are integers of at least about 7, preferably at least about 9, and M is a water-solubilizing cation, especially sodium, unsaturated sulfates such as oleyl sulfate, the C10-C18 alkyl alkoxy sulfates ("AEXS"; especially EO 1-7 ethoxy sulfates), C10-C18 alkyl alkoxy carboxylates (especially the EO 1-5 ethoxycarboxylates), the C10-18 glycerol ethers, the C10-C18 alkyl polyglycosides and their corresponding sulfated polyglycosides, and C12-C18 alpha-sulfonated fatty acid esters. If desired, the conventional nonionic and amphoteric surfactants such as the C12-C18 alkyl ethoxylates ("AE") including the so-called narrow peaked alkyl ethoxylates and C6-C12 alkyl phenol alkoxylates (especially ethoxylates and mixed ethoxy/propoxy), C12-C18 betaines and sulfobetaines ("sultaines"), C10-C18 amine oxides, and the like, can also be included in the overall compositions. The C10-C18 N-alkyl polyhydroxy fatty acid amides can also be used. Typical examples include the C12-C18 N-methylglucamides. See WO 9,206,154. Other sugar-derived surfactants include the N-alkoxy polyhydroxy fatty acid amides, such as C10-C18 N-(3-methoxypropyl) glucamide. The N-propyl through N-hexyl C12-C18 glucamides can be used for low sudsing. C10-C20 conventional soaps may also be used. If high sudsing is desired, the branched-chain C10-C16 soaps may be used. Mixtures of anionic and nonionic surfactants are especially useful. Other conventional useful surfactants are listed in standard texts.
  • Builders
  • Detergent builders can optionally be included in the compositions herein to assist in controlling mineral hardness. Inorganic as well as organic builders can be used. Builders are typically used in fabric laundering compositions to assist in the removal of particulate soils.
    The level of builder can vary widely depending upon the end use of the composition.
    Inorganic or P-containing detergent builders include, but are not limited to, the alkali metal, ammonium and alkanolammonium salts of polyphosphates (exemplified by the tripolyphosphates, pyrophosphates, and glassy polymeric meta-phosphates), phosphonates, phytic acid, silicates, carbonates (including bicarbonates and sesquicarbonates), sulphates, and aluminosilicates. However, non-phosphate builders are required in some locales. Importantly, the compositions herein function surprisingly well even in the presence of the so-called "weak" builders (as compared with phosphates) such as citrate, or in the so-called "underbuilt" situation that may occur with zeolite or layered silicate builders.
    Examples of silicate builders are the alkali metal silicates, particularly those having a SiO2:Na2O ratio in the range 1.6:1 to 3.2:1 and layered silicates, such as the layered sodium silicates described in U.S. Patent 4,664,839, issued May 12, 1987 to H. P. Rieck. NaSKS-6 is the trademark for a crystalline layered silicate marketed by Hoechst (commonly abbreviated herein as "SKS-6"). Unlike zeolite builders, the Na SKS-6 silicate builder does not contain aluminum. NaSKS-6 has the delta-Na2SiO5 morphology form of layered silicate. It can be prepared by methods such as those described in German DE-A-3,417,649 and DE-A-3,742,043. SKS-6 is a highly preferred layered silicate for use herein, but other such layered silicates, such as those having the general formula NaMSixO2x+1·yH2O wherein M is sodium or hydrogen, x is a number from 1.9 to 4, preferably 2, and y is a number from 0 to 20, preferably 0 can be used herein. Various other layered silicates from Hoechst include NaSKS-5, NaSKS-7 and NaSKS-11, as the alpha, beta and gamma forms. As noted above, the delta-Na2SiO5 (NaSKS-6 form) is most preferred for use herein. Other silicates may also be useful such as for example magnesium silicate, which can serve as a crispening agent in granular formulations, as a stabilizing agent for oxygen bleaches, and as a component of suds control systems.
    Examples of carbonate builders are the alkaline earth and alkali metal carbonates as disclosed in German Patent Application No. 2,321,001 published on November 15, 1973.
    Aluminosilicate builders are useful in the present invention. Aluminosilicate builders are of great importance in most currently marketed heavy duty granular detergent compositions, and can also be a significant builder ingredient in liquid detergent formulations. Aluminosilicate builders include those having the empirical formula: Mz(zAlO2)y]·xH2O wherein z and y are integers of at least 6, the molar ratio of z to y is in the range from 1.0 to about 0.5, and x is an integer from about 15 to about 264.
    Useful aluminosilicate ion exchange materials are commercially available. These aluminosilicates can be crystalline or amorphous in structure and can be naturally-occurring aluminosilicates or synthetically derived. A method for producing aluminosilicate ion exchange materials is disclosed in U.S. Patent 3,985,669, Krummel, et al, issued October 12, 1976. Preferred synthetic crystalline aluminosilicate ion exchange materials useful herein are available under the designations Zeolite A, Zeolite P (B), Zeolite MAP and Zeolite X. In an especially preferred embodiment, the crystalline aluminosilicate ion exchange material has the formula: Na12[(AlO2)12(SiO2)12]·xH2O wherein x is from about 20 to about 30, especially about 27. This material is known as Zeolite A. Dehydrated zeolites (x = 0 - 10) may also be used herein. Preferably, the aluminosilicate has a particle size of about 0.1-10 microns in diameter.
    Organic detergent builders suitable for the purposes of the present invention include, but are not restricted to, a wide variety of polycarboxylate compounds. As used herein, "polycarboxylate" refers to compounds having a plurality of carboxylate groups, preferably at least 3 carboxylates. Polycarboxylate builder can generally be added to the composition in acid form, but can also be added in the form of a neutralized salt. When utilized in salt form, alkali metals, such as sodium, potassium, and lithium, or alkanolammonium salts are preferred.
    Included among the polycarboxylate builders are a variety of categories of useful materials. One important category of polycarboxylate builders encompasses the ether polycarboxylates, including oxydisuccinate, as disclosed in Berg, U.S. Patent 3,128,287, issued April 7, 1964, and Lamberti et al, U.S. Patent 3,635,830, issued January 18, 1972. See also "TMS/TDS" builders of U.S. Patent 4,663,071, issued to Bush et al, on May 5, 1987. Suitable ether polycarboxylates also include cyclic compounds, particularly alicyclic compounds, such as those described in U.S. Patents 3,923,679; 3,835,163; 4,158,635; 4,120,874 and 4,102,903.
    Other useful detergency builders include the ether hydroxypolycarboxylates, copolymers of maleic anhydride with ethylene or vinyl methyl ether, 1, 3, 5-trihydroxy benzene-2, 4, 6-trisulphonic acid, and carboxymethyloxysuccinic acid, the various alkali metal, ammonium and substituted ammonium salts of polyacetic acids such as ethylenediamine tetraacetic acid and nitrilotriacetic acid, as well as polycarboxylates such as mellitic acid, succinic acid, oxydisuccinic acid, polymaleic acid, benzene 1,3,5-tricarboxylic acid, carboxymethyloxysuccinic acid, and soluble salts thereof.
    Citrate builders, e.g., citric acid and soluble salts thereof (particularly sodium salt), are polycarboxylate builders of particular importance for heavy duty liquid detergent formulations due to their availability from renewable resources and their biodegradability. Citrates can also be used in granular compositions, especially in combination with zeolite and/or layered silicate builders. Oxydisuccinates are also especially useful in such compositions and combinations.
    Also suitable in the detergent compositions of the present invention are the 3,3-dicarboxy-4-oxa-1,6-hexanedioates and the related compounds disclosed in U.S. Patent 4,566,984, Bush, issued January 28, 1986. Useful succinic acid builders include the C5-C20 alkyl and alkenyl succinic acids and salts thereof. A particularly preferred compound of this type is dodecenylsuccinic acid. Specific examples of succinate builders include: laurylsuccinate, myristylsuccinate, palmitylsuccinate, 2-dodecenylsuccinate (preferred), 2-pentadecenylsuccinate, and the like. Laurylsuccinates are the preferred builders of this group, and are described in European Patent Application 86200690.5/0,200,263, published November 5, 1986.
    Other suitable polycarboxylates are disclosed in U.S. Patent 4,144,226, Crutchfield et al, issued March 13, 1979 and in U.S. Patent 3,308,067, Diehl, issued March 7, 1967. See also Diehl U.S. Patent 3,723,322.
  • Fatty acids, e.g., C12-C18 monocarboxylic acids, can also be incorporated into the compositions alone, or in combination with the aforesaid builders, especially citrate and/or the succinate builders, to provide additional builder activity. Such use of fatty acids will generally result in a diminution of sudsing, which should be taken into account by the formulator.
    In situations where phosphorus-based builders can be used, and especially in the formulation of bars used for hand-laundering operations, the various alkali metal phosphates such as the well-known sodium tripolyphosphates, sodium pyrophosphate and sodium orthophosphate can be used. Phosphonate builders such as ethane-1-hydroxy-1,1-diphosphonate and other known phosphonates (see, for example, U.S. Patents 3,159,581; 3,213,030; 3,422,021; 3,400,148 and 3,422,137) can also be used.
  • Bleach
  • The detergent compositions herein may optionally contain bleaching agents or bleaching compositions containing a bleaching agent and one or more bleach activators. When present, bleaching agents will typically be at levels of from about 1% to about 30%, more typically from about 5% to about 20%, of the detergent composition, especially for fabric laundering. If present, the amount of bleach activators will typically be from about 0.1% to about 60%, more typically from about 0.5% to about 40% of the bleaching composition comprising the bleaching agent-plus-bleach activator.
    The bleaching agents used herein can be any of the bleaching agents useful for detergent compositions in textile cleaning, hard surface cleaning, or other cleaning purposes that are now known or become known. These include oxygen bleaches as well as other bleaching agents. Perborate beaches, e.g., sodium perborate (e.g., mono- or tetra-hydrate) can be used herein.
    Another category of bleaching agent that can be used without restriction encompasses percarboxylic acid bleaching 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 bleaching 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 a, issued November 1, 1983. Highly preferred bleaching agents also include 6-nonylamino-6-oxoperoxycaproic acid as described in U.S. Patent 4,634,551, issued January 6, 1987 to Burns et al.
    Peroxygen bleaching agents can also be used. Suitable peroxygen bleaching compounds include sodium carbonate peroxyhydrate and equivalent "percarbonate" beaches, sodium pyrophosphate peroxyhydrate, urea peroxyhydrate, and sodium peroxide. Persulfate bleach (e.g., OXONE, manufactured commercially by DuPont) can also be used.
    A preferred 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.
    Mixtures of bleaching agents can also be used.
    Peroxygen bleaching 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 beaches and activators useful herein.
    Highly preferred amido-derived bleach activators are those of the formulae: R1 N(R5)C(O)R2C(O)L or R1 C(O)N(R5)R2C(O)L wherein R1 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, R5 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, incorporated herein by reference.
    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, incorporated herein by reference. A highly preferred activator of the benzoxazin-type is:
    Figure 00170001
  • Still another class of preferred bleach activators includes the acyl lactam activators, especially acyl caprolactams and acyl valerolactams of the formulae:
    Figure 00170002
    wherein R6 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, incorporated herein by reference, which discloses acyl caprolactams, including benzoyl caprolactam, adsorbed into sodium perborate.
    Bleaching agents other than oxygen bleaching agents are also known in the art and can be utilized herein. One type of non-oxygen bleaching agent of particular interest includes photoactivated bleaching 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 beaches, especially sulfonate zinc phthalocyanine.
    If desired, the bleaching 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. 549,271A1, 549,272A1, 544,440A2, and 544,490A1; Preferred examples of these catalysts include MnIV 2(u-O)3(1,4,7-trimethyl-1,4,7-triazacyclononane)2(PF6)2, MnIII 2(u-O)1(u-OAc)2(1,4,7-trimethyl-1,4,7-triazacyclononane)2-(ClO4)2, MnIV 4(u-O)6(1,4,7-triazacyclononane)4(ClO4)4, MnIIIMnIV 4(u-O)1(u-OAc)2-(1,4,7-trimethyl-1,4,7-triazacyclononane)2(ClO4)3, MnIV(1,4,7-trimethyl-1,4,7-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.
  • Enzymes
  • Enzymes can be included in the formulations herein for a wide variety of fabric laundering purposes, including removal of protein-based, carbohydrate-based, or triglyceride-based stains, for example, and for the prevention of refugee dye transfer, and for fabric restoration. The enzymes to be incorporated include proteases, amylases, lipases, cellulases, and peroxidases, as well as mixtures thereof. 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.
    Enzymes are normally incorporated at levels sufficient to provide up to about 5 mg by weight, more typically about 0.01 mg to about 3 mg, of active enzyme per gram of the composition. Stated otherwise, the compositions herein will typically comprise from about 0.001% to about 5%, preferably 0.01%-1 % by weight of a commercial enzyme preparation. Protease enzymes are usually present in such commercial preparations at levels sufficient to provide from 0.005 to 0.1 Anson units (AU) of activity per gram of composition.
  • Suitable examples of proteases are the subtilisins which are obtained from particular strains of B. subtilis and B. licheniforms. Another suitable protease is obtained from a strain of Bacillus, having maximum activity throughout the pH range of 8-12, developed and sold by Novo Industries A/S under the registered trade name ESPERASE. The preparation of this enzyme and analogous enzymes is described in British Patent Specification No. 1,243,784 of Novo. Proteolytic enzymes suitable for removing protein-based stains that are commercially available include those sold under the tradenames ALCALASE and SAVINASE by Novo Industries A/S (Denmark) and MAXATASE by International Bio-Synthetics, Inc. (The Netherlands). Other proteases include Protease A (see European Patent Application 130,756, published January 9, 1985) and Protease B (see European Patent Application Serial No. 87303761.8, filed April 28, 1987, and European Patent Application 130,756, Bott et al, published January 9, 1985).
    Amylases include, for example, α-amylases described in British Patent Specification No. 1,296,839 (Novo), RAPIDASE, International Bio-Synthetics, Inc. and TERMAMYL, Novo Industries.
    The cellulase 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 DSM1800 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.
    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 British Patent 1,372,034. See also lipases in Japanese Patent Application 53,20487, laid open to public inspection on February 24, 1978. This lipase is available from Amano Pharmaceutical Co. Ltd., Nagoya, Japan, under the trade name Lipase P "Amano," hereinafter referred to as "Amano-P." Other commercial lipases include Amano-CES, lipases ex Chromobacter viscosum, e.g. Chromobacter viscosum var. lipolyticum NRRLB 3673, commercially available from Toyo Jozo Co., Tagata, Japan; and further Chromobacter viscosum lipases from U.S. Biochemical Corp., U.S.A. and Disoynth Co., The Netherlands, and lipases ex Pseudomonas gladioli. The LIPOLASE enzyme derived from Humicola lanuginosa and commercially available from Novo (see also EPO 341,947) is a preferred lipase for use herein.
    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 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 International Application WO 89/099813, published October 19, 1989, by O. Kirk, assigned to Novo Industries A/S.
    A wide range of enzyme materials and means for their incorporation 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 incorporation 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.
  • Other components which are comonly used in detergent compositions and which may be incorpoated into the detergent tablets of the present invention include chelating agents, soil release agents, soil antiredeposition agents, dispersing agents, brighteners, suds suppressors, fabric softeners, dye transfer inhibition agents and perfumes.
  • EXAMPLES
  • Figure 00230001
    Figure 00240001
  • Example 1
  • A detergent base powder of Composition 1 is prepared by the following steps:
  • Nonionic AE7/PEG4000 mixture is sprayed on the sodium perborate in a mixing drum. After spray on zeolite is used to dust the perborate impregnated with nonionic to eliminate its potential to bind the other powders; Ethoxylated hexamethylenediamine quat (the non-gelling binder) is sprayed on to the layered silicate, the bleach activator agglomerates and the carbonate; the contents of these two mixing drums are then mixed together with the remaining particulate materials of Composition 1 to form a homogeneous particulate.
  • 80 parts of the Composition 1 are then mixed in a mixing drum with 15 parts of sodium acetate and 5 parts of an effervescent mix consisting of 54.5% sodium bicarbonate and 45.5% citric acid.
  • Tablets are then made by introducing 55g of the mixture into a circular mold (diameter 54mm) and compressed to give tablets of 21 mm height and a density of 1.1 g/cc. The diametral fracture stress is 6 kPa.
  • The tablets are then dipped into a coating bath containing 90 parts of dodecanedioic acid mixed with 10 parts of Nymcel z6b16 heated to 140°C. The tablets are left in the bath for just long enough for 5g of coating to be applied, after which the tablets are removed and left to cool at 25°C for 24 hours. The diametral fracture stress is increased by the coating to greater than 20 kPa.
  • Example 2
  • A detergent base powder of Composition 1 is prepared by the following steps:
  • Nonionic AE7/PEG4000 mixture is sprayed on the sodium perborate in a mixing drum. After spray on zeolite is used to dust the perborate impregnated with nonionic to eliminate its potential to bind the other powders;
  • PEG200 (the non-gelling binder) is sprayed on to the layered silicate, the bleach activator agglomerates and the carbonate;
  • and thereafter the process of Example 1 is repeated except that 45 g of the composition are compressed into 45mm diameter tablet having a height of 23mm and a density of 1.1 g/cc.
  • The uncoated tablet has a diametral fracture stress of 10.2 kPa.
  • Detergent tablets having the following charateristics are produced:
    Figure 00260001

Claims (6)

  1. Detergent tablet comprising a core and a coating, the core having a diametral fracture stress of less than 15 kPa, and the core comprising a non-gelling binder, characterised in that the coated detergent tablet has a diametral fracture stress of at least 20 kPa.
  2. Detergent tablet according to claim 1 wherein the detergent core has a diametral fracture stress of less than 10 kPa, and preferably less than 5 kPa.
  3. Detergent tablet having a diametral fracture stess of at least 20 kPa, the tablet giving less than 18g residue at the end of the washing machine cycle under stressed test, the stressed test consisting of three tablets, each tablet weighing 60g, being placed in the bottom of the drum of a Miele® W831 washing machine, 2.5 kg of mixed fabric load being placed in the drum on top of the tablets, and the machine being run using a "whites/colours" short cycle of 30°C.
  4. Detergent tablet according to claim 3 wherein the tablet has a diametral fracture stess of at least 25 kPa.
  5. Detergent tablet according to claim 3 wherein the residue in the stressed test is less than 10g, and preferably less than 5g.
  6. Detergent tablet comprising a core and a coating, the core having a diametral fracture stress of less than 15 kPa, and the core comprising a non-gelling binder, characterised in that the coated detergent tablet has a diametral fracture stress of at least 20 kPa, and wherein the tablet gives less than 18g residue at the end of the washing machine cycle under stressed test, the stressed test consisting of three tablets, each tablet weighing 60g, being placed in the bottom of the drum of a Miele® W831 washing machine, 2.5 kg of mixed fabric load being placed in the drum on top of the tablets, and the machine being run using a "whites/colours" short cycle of 30°C.
EP97870116A 1997-08-08 1997-08-08 Detergent tablet Withdrawn EP0896052A1 (en)

Priority Applications (18)

Application Number Priority Date Filing Date Title
EP97870116A EP0896052A1 (en) 1997-08-08 1997-08-08 Detergent tablet
DE69730599T DE69730599T2 (en) 1997-08-08 1997-10-27 detergent tablet
ES97870166T ES2227661T3 (en) 1997-08-08 1997-10-27 DETERGENT PAD.
AT97870166T ATE275622T1 (en) 1997-08-08 1997-10-27 DETERGENT TABLET
EP97870166A EP0896053B1 (en) 1997-08-08 1997-10-27 Detergent tablet
BR9811880-3A BR9811880A (en) 1997-08-08 1998-08-04 Detergent tablet
CA002298832A CA2298832C (en) 1997-08-08 1998-08-04 Detergent tablet
AU86902/98A AU740611B2 (en) 1997-08-08 1998-08-04 Detergent tablet
EP98938364A EP1015546A1 (en) 1997-08-08 1998-08-04 Detergent tablet
US09/485,246 US6677295B1 (en) 1997-08-08 1998-08-04 Detergent tablet
TR2000/00361T TR200000361T2 (en) 1997-08-08 1998-08-04 Detergent tablet.
CN98809639A CN1272134A (en) 1997-08-08 1998-08-04 Detergent tablet
JP2000506304A JP2001512784A (en) 1997-08-08 1998-08-04 Tablet detergent
KR1020007001266A KR20010022671A (en) 1997-08-08 1998-08-04 Detergent tablet
PCT/US1998/016254 WO1999007819A1 (en) 1997-08-08 1998-08-04 Detergent tablet
MA25206A MA24896A1 (en) 1997-08-08 1998-08-06 DETERGENT TABLET
ZA987089A ZA987089B (en) 1997-08-08 1998-08-06 Detergent tablet
ARP980103921A AR016810A1 (en) 1997-08-08 1998-08-07 DETERGENT TABLET.

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
EP97870116A EP0896052A1 (en) 1997-08-08 1997-08-08 Detergent tablet

Publications (1)

Publication Number Publication Date
EP0896052A1 true EP0896052A1 (en) 1999-02-10

Family

ID=8231028

Family Applications (1)

Application Number Title Priority Date Filing Date
EP97870116A Withdrawn EP0896052A1 (en) 1997-08-08 1997-08-08 Detergent tablet

Country Status (6)

Country Link
EP (1) EP0896052A1 (en)
AR (1) AR016810A1 (en)
AT (1) ATE275622T1 (en)
DE (1) DE69730599T2 (en)
ES (1) ES2227661T3 (en)
ZA (1) ZA987089B (en)

Cited By (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2000052129A1 (en) * 1999-03-05 2000-09-08 The Procter & Gamble Company Production process for detergent tablet
WO2000060048A1 (en) * 1999-04-03 2000-10-12 Henkel Kommanditgesellschaft Auf Aktien Detergent forms with special tenside granulates
EP1061126A1 (en) * 1999-06-15 2000-12-20 Kao Corporation Solid-shaped detergent
EP1072674A1 (en) * 1999-07-27 2001-01-31 The Procter & Gamble Company Coated detergent tablet
EP1099487A2 (en) * 1999-11-09 2001-05-16 BeviClean GmbH Method, device and detergent additive for chemically cleaning pipelines
US6492320B2 (en) 1999-09-24 2002-12-10 Rohm And Hass Company Multifunctional, granulated pellet aid and process
US6503878B1 (en) * 1999-09-24 2003-01-07 Rohm And Haas Company Pellets
US6846794B1 (en) 1999-03-05 2005-01-25 The Procter & Gamble Company Production process for detergent tablet
US8097047B2 (en) 2008-04-02 2012-01-17 The Procter & Gamble Company Fabric color rejuvenation composition
US20170014313A1 (en) * 2015-07-15 2017-01-19 Nohbo, LLC Hygiene product tablet and methods of forming same
USD893800S1 (en) 2018-08-03 2020-08-18 Nohbo, LLC Hygiene product pod
US11045397B2 (en) 2019-11-06 2021-06-29 Nohbo, LLC Hygiene product pod and methods of using same
USD931526S1 (en) 2018-08-03 2021-09-21 Nohbo, LLC Hygiene product pod
US11744786B2 (en) 2018-01-18 2023-09-05 Nohbo, Inc. Hygiene product pod and methods of using same

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102010051226A1 (en) 2010-11-12 2012-05-31 Dental Care Innovation Gmbh Rinse-off tray with abrasive components
CA3051863C (en) 2017-02-02 2023-12-19 Water Pik, Inc. Dental cleaning tablets comprising glycine as abrasive

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS62225600A (en) * 1986-03-27 1987-10-03 ライオン株式会社 Tablet-shaped detergent
EP0522766A2 (en) * 1991-07-01 1993-01-13 Unilever Plc Detergent compositions in tablet form
JPH05331497A (en) * 1992-05-29 1993-12-14 Lion Corp Tablet detergent composition
EP0711827A2 (en) * 1994-11-14 1996-05-15 Unilever Plc Tablet detergent compositions
EP0716144A2 (en) * 1994-11-14 1996-06-12 Unilever Plc Detergent tablet having a water-soluble coating

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS62225600A (en) * 1986-03-27 1987-10-03 ライオン株式会社 Tablet-shaped detergent
EP0522766A2 (en) * 1991-07-01 1993-01-13 Unilever Plc Detergent compositions in tablet form
JPH05331497A (en) * 1992-05-29 1993-12-14 Lion Corp Tablet detergent composition
EP0711827A2 (en) * 1994-11-14 1996-05-15 Unilever Plc Tablet detergent compositions
EP0716144A2 (en) * 1994-11-14 1996-06-12 Unilever Plc Detergent tablet having a water-soluble coating

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
DATABASE WPI Section Ch Week 8745, Derwent World Patents Index; Class D25, AN 87-317677, XP002031238 *
DATABASE WPI Section Ch Week 9403, Derwent World Patents Index; Class D16, AN 94-023143, XP002051794 *

Cited By (19)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1035197A1 (en) * 1999-03-05 2000-09-13 The Procter & Gamble Company Production process for detergent tablet
WO2000052129A1 (en) * 1999-03-05 2000-09-08 The Procter & Gamble Company Production process for detergent tablet
US6846794B1 (en) 1999-03-05 2005-01-25 The Procter & Gamble Company Production process for detergent tablet
WO2000060048A1 (en) * 1999-04-03 2000-10-12 Henkel Kommanditgesellschaft Auf Aktien Detergent forms with special tenside granulates
US6645931B1 (en) 1999-06-15 2003-11-11 Kao Corporation Solid-shaped detergent
EP1061126A1 (en) * 1999-06-15 2000-12-20 Kao Corporation Solid-shaped detergent
US7067469B2 (en) 1999-06-15 2006-06-27 Kao Corporation Solid-shaped detergent
EP1072674A1 (en) * 1999-07-27 2001-01-31 The Procter & Gamble Company Coated detergent tablet
WO2001007559A1 (en) * 1999-07-27 2001-02-01 The Procter & Gamble Company Coated detergent tablet
US6503878B1 (en) * 1999-09-24 2003-01-07 Rohm And Haas Company Pellets
US6492320B2 (en) 1999-09-24 2002-12-10 Rohm And Hass Company Multifunctional, granulated pellet aid and process
EP1099487A3 (en) * 1999-11-09 2003-04-02 BeviClean GmbH Method, device and detergent additive for chemically cleaning pipelines
EP1099487A2 (en) * 1999-11-09 2001-05-16 BeviClean GmbH Method, device and detergent additive for chemically cleaning pipelines
US8097047B2 (en) 2008-04-02 2012-01-17 The Procter & Gamble Company Fabric color rejuvenation composition
US20170014313A1 (en) * 2015-07-15 2017-01-19 Nohbo, LLC Hygiene product tablet and methods of forming same
US11744786B2 (en) 2018-01-18 2023-09-05 Nohbo, Inc. Hygiene product pod and methods of using same
USD893800S1 (en) 2018-08-03 2020-08-18 Nohbo, LLC Hygiene product pod
USD931526S1 (en) 2018-08-03 2021-09-21 Nohbo, LLC Hygiene product pod
US11045397B2 (en) 2019-11-06 2021-06-29 Nohbo, LLC Hygiene product pod and methods of using same

Also Published As

Publication number Publication date
ZA987089B (en) 1999-02-16
ATE275622T1 (en) 2004-09-15
ES2227661T3 (en) 2005-04-01
AR016810A1 (en) 2001-08-01
DE69730599T2 (en) 2005-09-15
DE69730599D1 (en) 2004-10-14

Similar Documents

Publication Publication Date Title
EP0846756B1 (en) Coated detergent tablet and the process for producing the same
EP0846755B1 (en) Coated detergent tablet
US6169062B1 (en) Coated detergent tablet
EP0846754A1 (en) Coated detergent tablet
EP0896052A1 (en) Detergent tablet
EP0896053B1 (en) Detergent tablet
US6686329B1 (en) Multilayer detergent tablet with different hardness
EP1228190B1 (en) Bleach-containing detergent tablets
US6087311A (en) Coated detergent tablet
EP0971028A1 (en) Detergent tablet with high dissolution and mechanical characteristics
EP0971029B1 (en) Detergent tablet with high mechanical and dissolution characteristics
US6232284B1 (en) Coated detergent tablet with disintegration means
EP0979863A1 (en) Multilayer detergent tablet with different elasticities
US6559115B1 (en) Detergent tablet with high mechanical and dissolution characteristics
EP0979862A1 (en) Multilayer detergent tablet with different hardness
US6677295B1 (en) Detergent tablet
US6429185B1 (en) Process for producing a powder from a packaged tablet
EP0949327A1 (en) Shape and strength of detergent tablets
EP0972827B1 (en) Process for producing a powder from a tablet
WO2001025391A1 (en) Detergent tablet with high dissolution and mechanical characteristics
WO2000004127A1 (en) Process for producing a powder from a packaged tablet

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AT BE CH DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE

AX Request for extension of the european patent

Free format text: AL;LT;LV;RO;SI

AKX Designation fees paid
STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE APPLICATION IS DEEMED TO BE WITHDRAWN

18D Application deemed to be withdrawn

Effective date: 19990811

REG Reference to a national code

Ref country code: DE

Ref legal event code: 8566