NZ211588A

NZ211588A - Detergent composition containing sodium perborate monohydrate

Info

Publication number: NZ211588A
Application number: NZ211588A
Authority: NZ
Inventors: M Julement; M Marchal; L Laitem
Original assignee: Colgate Palmolive Co
Priority date: 1984-04-09
Filing date: 1985-03-26
Publication date: 1987-06-30
Also published as: MX162806A; AT394864B; BR8501621A; KR850007609A; FI85601B; FI851385L; FI851385A0; IT1181629B; ZA852201B; ES542030A0; IT8547931A1; SE8501590D0; FI85601C; FR2562557B1; DK158385A; KR920004793B1; LU85845A1; GR850881B; IT8547931A0; BE902144A

Description

<div class="application article clearfix" id="description"> New Zealand Paient Spedficaiion for Paient Number £11 588 211581 ' U 2'. P AT EHT OFFICE ?6MAR i985 • r- -.aw1 u- f* ~ -i. J NO DRAWINGS 5.iority Dar-i(.•-■: J^rAfe-Al^s. Complete S::...-;.;_.:;:;:i ; ;;orf. C:,"L • Gx\Ql.\6fe.cv\p3jQ^ •Q&.&l.'i). ' Publication C£to; ... 1987. P.O. Journal, No: t.7>£jU, Patents Form No. 5 Number PATENTS ACT 1953 Dated COMPLETE SPECIFICATION LIQUID BLEACHING LAUNDRY DETERGENT COMPOSITION xffWe COLGATE-PALMOLIVE COMPANY, 300 Park Avenue, New York, New York 1002 2, United States of America, a corporation organised under the laws of the State of Delaware, United States of America do hereby declare the invention for which ji/we pray that a Patent may be granted to bdk/us, and the method by which it is to be performed, to be particularly described in and by the following statement: - 1 - m 21158 This invention relates to nonaqueous liquid heavy duty laundry detergents. In accordance with one aspect of this invention, a highly effective and stable nonaqueous liquid heavy duty laundry detergent is prepared by dispersing a solid builder salt, sodium perborate monohydrate and a solid activator for the perborate in a substantially anhydrous liquid nonionic surfactant and grinding the dispersion to reduce the particle w. size of those solids to less than about 10 microns, e.g., to an average particle size of 2 to 10 microns or even lower, such as 1 micron. Preferably, in the ground product, less than about 20% by weight (more preferably less than about 10% by weight) of the suspended particles have diameters above 10 microns. It will be understood that as the particle size is decreased, by grinding, fresh reactive surfaces are exposed and the surface area available for reaction is increased. Also, the energy involved in the fine grinding operation necessarily i causes localized rises in temperature within the mixture being ^ ground (even though the grinding mill is cooled, e.g. by cold water running through a jacket of the mill, during grinding). Despite this, the compositions of the invention are highly stable, showing little, if any, loss of bleaching activity during grinding or on storage. - 2 - 21158 In the grinding operation it is preferred that the proportion of solid ingredients be high enough (e.g., at least about 40% such as about 50%) so that the solid particles are in contact vith each other and are not substantially shielded from one another by the nonionic surfactant liquid. Mills which employ grinding balls (ball mills) or similar mobile grinding elements have given very good results. Thus, one may use a laboratory batch attritor having 8 mm diameter steatite grinding balls. For larger scale work a continuously operating mill in which there are 1 mm or 1.5 mm diameter grinding balls working in a very small gap between a stator and a rotor operating at a relatively high speed (e.g., a CoBall mill) may be employed; when using such a mill it is desirable to pass the blend of nonionic surfactant and solids first through a mill which does not effect such fine grinding (e.g., a colloid mill) to reduce the particle size to less than 100 microns (e.g., to about 40 microns), prior to the step of grinding to an average particle diameter below about 10 microns in the continuous ball mill. It is preferred that the solid builder salt be an alkali metal polyphosphate such as sodium tripolyphosphate ("TPP") Other suitable polyphosphates include the pyrophoshates such as tetrasodium pyrophosphate and metaphosphates. In place of all or part of the polyphosphate one or more other detergent builder - 3 - 21158 r> V J salts may be used, such as alkali metal carbonates or bicarbon-ates, silicates, or organic builders such as polycarboxylates. Typical suitable builders are those disclosed in U.S. Patents 4,316,812; 4,264,466 and 3,630,929. The preferred activator is tetraacetyl ethylene diamine ("TAED"). Another suitable activator is glucose pentaacetate. Other suitable activators are those disclosed in U.S. Patent 4,264,466 or in column 1 of U.S. Patent 4,430,244. Polyacylated compounds are preferred activators. The following Examples are given to illustrate this invention further. All proportions in this application are by weight unless otherwise indicated. Example 1 The following compositions A and B are each ground for 30 minutes at room temperature in a Wieneroto W-l.S attritor with 8 mm diameter steatite 'balls, producing a liquid suspension in which the average particle size of the ground material is below about 10 microns in each case Nonionic surfactant Acid-converted nonionic surfactant TPP • • PROPORTIONS A B_ 35 32.57 16 16 30 30 - 4 - A 2115 N PROPORTIONS Sodium salt of ethylenediamine tetramethy1ene phosphonic acid (EDITEMPA) 1.5 1.5 Copolymer of methacrylic acid and maleic anhydride completely converted to sodium salt form (Sokalan CP5) 4 4 Sodium carbonate 2.5 2.5 Sodium perborate monohydrate (NaBOjH 0) 4.5 Sodium perborate tetrahydrate — 6.93 TAED 5 5 Optical brighteners of stilbene 4 type 0.5 0.5 Enzyme slurry (Protease slurried in nonionic surfactant) 1 1 Each composition contains 0.72% active O2 and the content of unbound water of the ingredients is less than 1%. After 48 hour aging at 35°C, composition A is still liquid while composition B has become substantially solid (its yield stress has increased to a value greater than 20 Pascals). After 5 day aging at 35°C, analysis for available peracetic acid indicates that the effective loss of TAED on grinding and aging is 7% fox composition A and 45% for composition B. The nonionic surfactant used in this Example comprises a mixture of equal parts of: (a) a relatively water soluble nonionic surfactant - 5 - J • 2115 _v which forms a gel when mixed with water at 25°C, specifically a to alkanol which has been alkoxylated to introduce 10 ethylene oxide and 5 propylene oxide units per alkanol unit and (b) a less water-soluble nonionic surfactant, specifically a to alkanol which has been alkoxylated to introduce 4 ethylene oxide and 7 propylene oxide units per alkanol unit. The acid-converted nonionic surfactant is a half ester of succinic acid and a nonionic surfactant (specifically ethoxy-lated to £^5 alkanol having about 5 ethylene oxide units per molecule of alkanol). This half ester can be produced by the reaction of succinic anhydride and the nonionic surfactant at elevated temperature (e.g., 60°C) preferably in the presence of a small amount of catalyst such as pyridine. The resulting acid-terminated product acts in the compositions as an antigelling agent. It reduces the temperature at which the nonionic surfactant forms a gel with cold water and thus aids in the dispensing of the compositions during operation of automatic home laundry machines at winter temperatures. Other carboxylic acid materials soluble in the nonionic surfactant may be used for this purpose. The TPP is a blend of anhydrous TPP and a small amount of TPP hexahydrate such that the chemically bound water content is about 3%, which corresponds to about one H2O per pentasodium tripolyphosphate molecule. Such TPP may be produced by treating anhydrous TPP with a limited amount of water. The presence of - 6 - 21 1588 the hexahydrate slows down the rapid rate of solution of the TPP in the wash bath and inhibits caking. One suitable TPP is sold under the name Thermphos NW; the particle size of this TPP as supplied is in the neighborhood of AOO microns; its phase I content is about 60%. In preparing the mixture before grinding it is preferred to add the solid ingredients to the nonionic surfactant, with the TPP being added last. The mixture dispenses readily with cold water in the automatic washing machine. Its specific gravity is about 1.25. It gives excellent washing when used at a dosage of about 100 grams per wash load (as compared with 170 grams per wash load £or the usual heavy duty laundry detergent powders) in conventional European home laundry machines (which employ about 20 liters of water for the washing bath) in which the water is heated, during washing to about 60°C. EXAMPLE 2 A ground composition is prepared as in Example 1 from the following ingredients in the stated proportions: nonionic surfactant 40.8 TPP 49.8 Ethylene diamine tetraacetic acid 1.2 TAED 4 . 5 Sodium perborate mono- hydrate 3.6 Hydroxylamine sulfate 0.1 - 7 - 211588 The hydroxylamine sulfate acts to inhibit the undesirable bleach-decreasing action of the enzyme, catalase, present in soiled clothes. As is well known, the nonionic synthetic surfactants are characterized by the presence of an organic hydrophobic group and an organic hydrophilic group and are typically produced by the condensation of an organic aliphatic or alkyl aromatic hydrophobic compound with ethylene oxide (hydrophilic in nature). Practically any hydrophobic compound having a carboxy, hydroxy, amido or amino group with a free hydrogen attached to the nitrogen can be condensed with ethylene oxide or with the polyhydration product thereof, polyethylene glycol, to form a nonionic detergent. The length of the hydrophilic or polyoxyethylene chain can be readily adjusted to achieve the desired balance between the hydrophobic and hydrophilic groups. Typical suitable liquid nonionic surfactants are those disclosed in U.S. patents 4,316,812 and 3,630,9'29, as well as those described and listed in the discussion of nonionic surfactants in Kirk-Othmer "Encyclopedia of Chemical Technology", 3rd Edition, Vol. 22 (1983) pages 360 to 379. The activator usually interacts with the peroxygen compound to form a peroxyacid bleaching agent in the wash water. It is preferred to include a sequestering agent of high com-plexing power to inhibit any undesired reaction between such peroxyacid and hydrogen peroxide in the wash solution in the presence of metal ions. Such a sequestering agent is an organic - 8 ? 11588 2 + compound which is able to form a complex with Cu ions, such that the stability constant (pK) of the complexation is equal to or greater than 6, at 25°C, in water of an ionic strength of 0.1 mole/liter, pK being conventionally defined by the formula: pK=-log K where K represents the equilibrium constant. Thus, for example, the pK values for complexation of copper ion with NTA and EDTA at the stated conditions are 12.7 and 18.8, respectively. Suitable sequestering agents include the sodium salts of nitrilotriacetic acid (NTA); ethylene diamine tetraacetic acid (EDTA); diethylene triamine pentaacetic acid (DETPA); diethylene triamine pentamethylene phosphonic acid (DTPMP); and ethylene diamine tetramethylene phosphonic acid (EDITEMPA). Other ingredients which may be included in the composition are enzymes (e.g. proteases, amylases or lipases or mixtures thereof); optical brighteners, antiredeposition agents (e.g. sodium carboxymethylcellulose), colorants (e.g. pigments or dyes) etc. The composition may also contain an inorganic insoluble thickening agent or dispersant of very high surface area such as finely divided silica of extremely fine particle size (e.g. of 5-100 millimicrons diameter such as sold under the name Aerosil) or the other highly voluminous inorganic carrier materials disclosed in U.S. patent 3,630,929, in proportions of 0.1-10%, e.g. 1 to 5%. It is preferable, however, that the compositions - 9 - \ .Xr- f- 211588 be substantially free of such compounds and of other silicates, it has been found, for instance, that silica and silicates promote an undesired decomposition of the peroxyacid formed in the wash bath. In the compositions of the invention, typical pro-portions of the ingredients are as follows: Suspended detergent builder, within the range of about 10 to 60%, such as about 20 to 50%, e.g., about 25 to 40%; Liquid phase comprising nonionic surfactant (and, optionally, dissolved carboxylic acid material), within the range of about 30 to 70%, such as about 40 to 60%; this phase may also include a diluent such as a glycol, e.g., polyethylene glycol (e.g., "PEG 400") or hexylene gylcol. Carboxylic acidic antigelling agent, in the range of about 0.01 to 1 part per part of nonionic surfactant, such as about 0.05 to 0.6 part, e.g. about 0.2 to 0.5 part; Sodium perborate monohydrate, in the range of about 2 to 15%, such as about 4 to 10%; Activator in the range of about 1 to 8%, such as about 3 to 6%. The unbound moisture content of the composition should be less than about 2% preferably below about 1%, such as about Jj% or less . While it is most convenient and effective to grind all the solid ingredients together it is within the broader scope of the invention to grind separate suspensions of individual ingredients or groups of ingredients and combine these together after such grinding. - 10 - </div>

Claims

<div class="application article clearfix printTableText" id="claims"> © 211588 In this application all proportions are by weight unless otherwise indicated. In the Examples, atmospheric pressure is used unless otherwise indicated. It is understood that the foregoing detailed description is given merely by way of illustration and that variations may be made therein without departing from the spirit of the invention as defined in the appended claims. f O ' J 3 - 11 - 211588 WHAT WE CLAIM IS :

1. A substantially anhydrous liquid heavy duty laundry detergent composition comprising particles of solid sodium perborate monohydrate, particles of solid activator for the perborate, and particles of solid builder salt, all dispersed in a liquid nonionic surfactant, the sizes of said particles being less than 10 microns.

2. A composition as in Claim 1 in which the activator comprises tetraacetyl ethylene diamine and the builder salt comprises pentasodium tripolyphosphate.

3. A composition as in Claim 1 produced by grinding a suspension in said liquid of said solids, said solids having particle sizes of at least 40 microns before said grinding.

4. A composition as in Claim 1 comprising 10 to 60% by weight of said builder salt, 2 to 15% by weight sodium perborate monohydrate and 1 to 8% by weight activator.

5. A composition as in Claim 4 in which the amount of i said builder /alt Is 25 to 40% by weight.

6 A composition as in Claim 5 in which the activator comprises tetraacetyl ethylene diamine, the builder salt comprises pentasodium tripolyphosphate, said composition having been produced by grinding a suspension of said solids in said liquid, said solids having particle sizes of at least 40 microns before said grinding.

7. A composition as in Claim 6 substantially free of silica or silicates. WEST-WALKER, McCABE j NX PATENT OFFICE per: ATTORNEYS THE APPLICANT j RECEIVED | - 1 2 - </div>