MXPA97004368A - Detergent pills - Google Patents

Abstract

A detergent tablet comprising at least 50% by weight of a non-phosphate former and from 0 to 20% by weight of a phosphate former having a binder of from 0.3 to 5% by weight of a binder is incorporated therein. a neutralized polymer of hydrophilic or hydrophobic monomers having a glass transition temperature (Tg) from 40 to 120øC, whose monomers comprise (meta) acrylic acid, maleic anhydride, (meta) acrylic hydroxyalkyl (meta) acrylates, (meta) ) alkylhydroxy acrylates, (meth) acrylic acid alkyl or styrene, the polymer has a molecular weight from 10,000 to 120,000. The tablet has improved physical properties compared to those of the prior art

Description

DETERGENT PILLS The present invention relates to detergent bars and bars, and more specifically to bars and detergent bars containing high levels of non-phosphate ingredients. In the past, phosphates have been used in detergents, generally to avoid precipitation of calcium salt. Phosphate-containing detergents can be made with the same formulation in both powder and tablet form, since the phosphates impart good properties to it in the form of tablets. However, at present, phosphates are generally used in detergents in very low amounts or are not used at all, and in their place are used other formers such as zeolite, citrates, silicate silicates in layers, disilicates, etc. Generally, these formers are available in powder or granule form, and can be easily mixed dry or granular in powder detergent formulations. However, its granulometry and other physical properties such as for example giving the form of tablets to the powder formulation in very difficult. Therefore, in order to give the tablet form to these formulations, it is generally necessary to reformulate the detergent, or add binding agents to the powder before forming the tablets. Examples of these linking agents include fatty alcohols or fatty acids such as for example lauryl alcohol or stearic acid. For example, GB 989683A presents covering the detergent tablet with a water-soluble film-forming polymer such as polyvinyl alcohol. However, they are generally difficult to use because they are solid at room temperature, and also reduce the average dissolution of the tablet, which is not desirable for a detergent. Other binder substances which are used include sodium salts of (meta) acrylic acid homo- or copolymer, as presented in EP 579659A, which are agglomerated with other detergent components, then the agglomerate is dried and made in the form of a tablet. The pellets produced with these binder substances have improved physical and solubility properties; however, these properties are still able to have improvements to be comparable with those tablets containing phosphate formers for example. For manufacturing bars or detergent tablets, extrusion is frequently used, and manufacturers often experience difficulties in maintaining satisfactory mechanical strength in the bars, which often break during production, handling or storage. An alternative for incorporating binder substances into a formulation to be formed into tablets is to make the formulation into a tablet and then to coat the tablet with a compound that improves its resistance to rupture and the speed of dissolution. However, pads that only have an external coating of this material tend to dissolve very quickly once the cover is removed with the washes, which results in lower washing results. In addition, the coating of a previously formed tablet is, of course, an additional step in the manufacturing process, which is not the most preferred. GB 2040980 presents a coating for a detergent tablet with nonionic polyoxyalkylene surfactants, although in this case the coating is present for its surfactant properties. Therefore, there is a need for a detergent tablet that contains high levels of a non-phosphate former that has robust physical properties, particularly that does not crumble and powder, that can be inexpensively manufactured, and that provides results detergents as good or better than current pills. We have discovered that these tablets can be achieved by giving the pellet form to the particular detergent formulation that is previously mixed with a particular proportion of polymeric binder substances., so that the material of the binder substance is incorporated throughout the tablet, and not only on the surface. According to one aspect, the present invention provides a detergent tablet comprising at least 50% by weight of a non-phosphate former and from 0 to 20% by weight of a phosphate former having a binder incorporated therein. from 0.3 to 5% by weight of a neutralized polymer of hydrophilic or hydrophobic monomers having a glass transition temperature (Tg) from 40 to 120 ° C, whose monomers comprise (meta) acrylic acid, maleic anhydride, (meta) acids hydroxyalkyl acrylic, (meta) alkyl acrylates, (meta) acrylates alkylhydroxy, (meth) acrylic acid alkyl or styrene, the polymer has a molecular weight of 10,000 to 120,000. By "incorporated into the present" we mean that the binder substance is distributed throughout the body of the tablet, and is not simply a coating on the surface. The inorganic former comprises citrates, silicates, disilicates, zeolites, carbonates, bicarbonates. Other organic chelants can also be used.

A further aspect of the invention provides a process for producing a detergent tablet comprising the steps of a) agglomerating a composition comprising at least 50% by weight of a non-phosphate former and from 0 to 20% by weight of a phosphate former and from 0.3 to 5% by weight of a hydrophobic or hydrophilic monomer polymer having a glass transition temperature (Tg) from 40 to 120 ° C, whose monomers comprise acid (meta) acrylic, maleic anhydride, (meta) acrylic hydroxyalkyl acids, (meta) acrylates alkyl, (meta) acrylates alkylhydroxy, acids (meta) acrylic alkyl or styrene, the polymers have a molecular weight from 10,000 to 120,000, and then b ) to give tablet form to the resulting agglomerate. If present, the amount of phosphate former may be from 5% by weight or less, preferably from 0 to 1% by weight and more preferably from 0 to 0.1% by weight. It is necessary to neutralize the polymer to be soluble. The molecular weight of the polymer is preferably from 25,000 to 95,000, more preferably from 40,000 to 500,000, and its preferable Tg is between 40 and 100 ° C. The preferred levels in the tablet are from 0.5 to 2% by weight. The detergent tablets made in accordance with the invention exhibited excellent physical properties compared to the known tablets having high levels of non-phosphate formers.

EXAMPLES Formulation A of dishwashing tablets (all quantities are in percentage by weight) Calcium citrate dihydrate 35 Carbonate 8 Perborate 10 Tetraacetylethylene diamine (TAED) 3 Na salt of polyacrylic acid (MW 4500) 4.5 Nonionic surfactant (plurafac LF 403) 1 Bicarbonate 38 -38.5 Assistant to give tablet form 0-0..5 The dishwashing tablets were formulated according to the above formula, each containing an assistant for the formation of the different tablet, as mentioned in Table 1 below. Then, the tablets were visually evaluated and also the hardness using a Schleuniger 60 tablet tester. The results are given below. The hardness was evaluated after one hour, and measured in kPa. MMA = methyl methacrylate, MAA = methacrylic acid, BA = butyl acrylate, HEMA = hydroxyethyl methacrylate, EHA = 2-hydroxyethylacrylate TABLE 1 Assistant on the Aspect tablet formation Mw Tg visual hardness None Impossible to make tablet 0. 5% water 3.5 Moist and crumbles 47MMA / 25BA / 18MAA / 10HEMA 45000 20.5 95 ° C Excellent 47MMA / 25BA / 18MAA / 10HEMA 88000 13.0 98 ° C Acceptable 47MMA / 25BA718MAA / 10HEMA 11600 5.0 100 ° C Humid and crumbling 47MMA / 25BA / 18MAA / 10HEMA 14800 5.0 99 ° C Very undesirable 52. 5MMA / 29.5BA / 18MAA 20000 17.0 80 ° C Good 40estir./30EHA/25AN/5MAA 55800 12.5 51 ° C Acceptable 80EHA / 20AA 15000 11.0 Acceptable 62BMA / 38AA 10000 4.5 Wet and crumbling 2.5 Wet Polyurethane and crumbling "Acceptable", "Good" and "Excellent" refers to the hardness of the tablet and the resistance to collapse and also to the visual impression. "Acceptable" for example, means that, despite the fact that an appropriate tablet is formed, the edges of the tablet are not very defined and in some way are not even or equal.

II. LAVAPLATOS TABLET FORMULATED ACCORDING TO EP 579659A Formula B was prepared according to what is taught in EP 579659A, and then its physical properties were evaluated when adding an assistant for tablet formation. The tablet-forming assistant employed has the formula 47MMA / 25BA / 18MAA / 1OHEMA, Mw 45000, Tg about 98 ° C.

FORMULA B: Sodium carbonate 46.7% Sodium sulphate 1% Dry copolymer * 10.2% Sodium citrate 10.3% Sodium disilicate 20.5% Sodium perborate monohydrate 7.1% TAED 2.1% Nonionic surfactant 2.1% * Sodium salt of an acid copolymer acrylic and maleic HARDNESS Comments Visual appearance FORMULA A Medium laminar rupture + 0 .5% water FORMULA B 15.0 good non-laminar + 0.5% aid for tablet formation By "laminar" it is meant that after pressing the upper and lower surface of the tablet is compressed by a compressor machine to such a degree that it is separated from the body of the tablet as laminar portions, the main body of the tablet being of a smaller solid consistency.

III. WASHING TESTS The formulas mentioned above were tested in performance compared to commercially available pills. The commercial tablet 1 contains: < 5% nonionic surfactant 5-15% oxygenated bleach > 30% phosphate enzymes The commercial tablet 2 contains: < 5% nonionic surfactant 5-15% oxygenated bleach, polycarboxylate enzymes, carbonate, citrate, activator, perfume Conditions: tablet 1 / washed Stain: milk + margarine Water: 600 ppm hardness as CaC03 Scale: 0 = perfect 4 = heavy film in glasses DETERGENT Pill A-without aid for A + 0.5% help commercial pair training formation 1 pellets tablets AMOUNT 25.5 g 23.8 g (as 23 g powder) Film / stain 0/1 1/1 0/0 4 cycles Film / stain 0.5 / 1 1.5 / 1.5 1/0 8 cycles Note: Formula A does not contain enzymes that can improve performance. IV. DETERGENT ACTION Evaluations of wood patches impregnated with tea were carried out. Thin strips of wood, laminated on one side with plastic, were impregnated on one side with tea and the whiteness of the patch was evaluated before and after washing.

Commercial Formula Formula A 1 A + 0.5% help Whiteness 77.38 75.56 76.12 before washing Whiteness 80.34 82.86 82.60 after washing (greater than best) Yellow scale 2.85 3.85 3.18 before washing Yellow scale 1.67 0.37 0.31 (lower than best) The previous results showed that the presence in the The formula for the formation of the tablet does not have a negative effect on the performance of the detergent action or the stability of the bleach. V. VARIATION IN THE FORMULATION An additional detergent formulation was prepared with the composition given below, and the tablets formulated with 0.5% assistant for tablet formation were evaluated for hardness. C Citrate 20% Carbonate 8% Perborate 10% TAED 3% Homopolymer 4.5% Nonionic surfactant 1% Bicarbonate 53.5% Disilicate 0 Results: hardness of the pellets after aging for 1 hour Formula Hardness (kPa) A + 0.25% help for pellets 12 A + 0.5% help for pills 19 B + 0.5% help for pills 20 C + 0.5% help for pills 18 VI. AVERAGE DISSOLUTION The pellets were placed in a wire basket in a typical glass front dishwashing machine, and the time to completely dissolve during a normal wash cycle was visually observed. Commercial 1 22 minutes Commercial 2 33 minutes Formula B 27 minutes Formula A + Help for past. 24 minutes Formula B + Help for past. 21 minutes The commercial tablets 1 and 2 began to dissolve a little later and then they were suddenly undone when they got wet. The formulas A + help for pills and B + help for pills were dissolved more regularly from the beginning to the end of the cycles.

Claims (10)

1. CLAIMS 1. A detergent tablet comprising at least 50% of a non-phosphate former and from 0 to 20% by weight of a phosphate former, which has incorporated therein as a binder from 0.3 to 5% by weight of a polymer neutralized from hydrophilic or hydrophobic monomers having a glass transition temperature (Tg) from 40 to 120 ° C, whose monomers comprise (meta) acrylic acid, maleic anhydride, (meta) acrylic hydroxyalkyl acids, (meta) alkyl acrylates, ( meta) alkylhydroxy acrylates, (meth) acrylic alkyl or styrene acids, the polymer has a molecular weight from 10,000 to 120,000.
2. 2. The process for producing a detergent tablet comprising the steps of a) agglomerating a composition comprising at least 50% by weight of a non-phosphate former and optionally up to 20% by weight of a phosphate former and from 0.3 to 5% by weight of a neutralized hydrophobic or hydrophilic monomer polymer having a glass transition temperature (Tg) from 40 to 120 ° C, whose monomers comprise (meta) acrylic acid, maleic anhydride, hydroxyalkyl (meta) acrylic acids, (meta ) alkyl acrylates, (meth) alkylhydroxy (meth) acrylates, (meth) acrylic alkyl or styrene acids, the polymers have a molecular weight from 10,000 to 120,000, and then b) give the pellet form to the resulting agglomerate.
3. 3. The process or tablets according to claim 1, wherein the polymer has a molecular weight from 25,000 to 95,000.
4. 4. The process or tablet according to any preceding claim, wherein the polymer has a molecular weight from 40,000 to 50,000.
5. The process or tablet according to any of the preceding claims, wherein the amount of phosphate former is from 0 to 5% by weight.
6. 6. The process or tablet according to claim 5 wherein, the amount of phosphate former is from 0 to 1% by weight, preferably from 0 to 0.1% by weight. The process or tablet according to any of the preceding claims, wherein the polymer has a Tg of between 40 to 100 ° C. The process or tablet according to any of the preceding claims, wherein the polymer comprises methyl methacrylate, butyl acrylate, methacrylate, hydroxyethyl methacrylate or 2-hydroxyethyl acrylate units. The process or tablet according to any one of the preceding claims, wherein the polymer comprises 47% by weight of methyl methacrylate, 25% by weight of butyl acrylate, 18% by weight of methacrylic acid and 10% by weight of hydroxyethylmethacrylate. The process or pellet according to any of the preceding claims, wherein the inorganic former comprises citrate, silicate, disilicate, zeolite, carbonate or bicarbonate.