EP0445852A1

EP0445852A1 - Detergent composition

Info

Publication number: EP0445852A1
Application number: EP91200232A
Authority: EP
Inventors: Johannes Pronk; Emery George Philomena Cornelissens
Original assignee: Sara Lee DE NV
Current assignee: Sara Lee DE NV
Priority date: 1990-02-05
Filing date: 1991-02-05
Publication date: 1991-09-11
Also published as: NL9000272A; AU7025391A; NO910422D0; NO910422L; AU635107B2

Abstract

A phosphate-free main wash detergent composition comprises

a. a builder system based on
- 1. at least 20 wt.% soluble silicate (based on the detergent composition) in an Na₂O/SiO₂ ratio less than or equal to 1/2,
- 2. sodium carbonate and/or sodium bicarbonate
b. 0.5 to 10 wt.% anionic polymer
c. anionic and/or non-ionic surfactant,
and
d. if desired, conventional additives.

Description

A main wash detergent composition

The invention relates to a phosphate-free main wash detergent composition comprising

a.: a builder system
b.: 0.05 to 10 wt.% anionic polymer
c.: anionic and/or non-ionic surfactant,
and
d.: if desired, conventional additives.

Conventional main wash detergent compositions are based on a builder system consisting of, e.g., sodium carbonate and/or sodium bicarbonate, optionally in combination with silicates. These silicates are mainly insoluble, poorly soluble or slowly soluble silicates such as sodium aluminosilicate and metasilicate. Since the combination of soda and silicate generally gave rise to incrustation, the content thereof was reduced, while furthermore the use of anionic polymers was introduced. The latter also had a positive effect on the reduction of incrustation.
German patent application 38 25 858 discloses a phosphate-containing detergent composition having incorparated therein a metasilicate and an acrylic acid (co)polymer.
The use of the known insoluble or poorly soluble silicates has the drawback that this material is relatively expensive, while furthermore it is rather detrimental to the environment. Moreover, the use thereof leads to fibre incrustation.
Surprisingly, it has been found possible to manufacture a phosphate-free detergent composition starting from the combination of sodium carbonate and/or sodium bicarbonate with at least 20 wt.% soluble silicate, without any problems with incrustation, there being obtained an excellent primary and secondary detergency. Since insoluble or poorly soluble silicates are not used, the drawbacks observed in the prior art do not occur.
The invention therefore relates to a main wash detergent composition comprising

a. a builder system based on
- 1. at least 20 wt.% soluble silicate (based on the detergent composition) in an Na₂O/SiO₂ ratio less than or equal to 1/2,
- 2. sodium carbonate and/or sodium bicarbonate
b. 0.05 to 10 wt.% anionic polymer
c. anionic and/or non-ionic surfactant,
and
d. if desired, conventional additives.

An essential component of the detergent composition according to the invention is formed by the soluble silicate preferably having a solubility of at least 2 g/1 in demiwater. The amount thereof is preferably at least 25 wt.%.
The soluble silicate has an Na₂O/SiO₂ ratio less than or equal to 1/2 and is preferably selected from the group consisting of disilicate, trisilicate and laminar silicate.
The detergent composition according to the invention also contains a polymeric component. This polymeric component consists of at least one anionic polymer and has, in combination with the builder system based on soda and soluble silicate, the surprising effect that the incrustation is optimally reduced.
Although a product completely free from phosphorus compounds is preferred, the detergent composition may also contain a phosphonate in another embodiment of the invention. This phosphonate may be present in amounts of 0.1 to 5 wt.%, based on the weight of the detergent composition. Preferably, the content is not more than 1 wt.%. The effect of the phosphonate is that the incrustation is reduced even more strongly, while also a bleaching agent optionally present is stabilised.
Apart from the above-mentioned components, the detergent composition may also contain other conventional components such as filler, bleach system, enzyme, dye, optical brightener, perfume, hydrotrope, fabric softener, soap, antiredeposition agent etc. The amounts and exact nature of these components are not critical. The components conventional in detergent compositions may be used in normal amounts. In general, the amount of these components, with the exception of the filler and the water, range from 0.5 to 10 wt.%. If a filler is used, the amount thereof preferably ranges from 1 to 50 wt.%. Preferably, however, no filler is used. The amount of free water in the system is preferably kept as low as possible. Conventional amounts range from 0.1 to 5 wt.%.
The anionic polymer is used in an amount of from 0.5 to 10 wt.%. The anionic polymer preferably used is a polymer with sulphonate groups, more in particular a polymer or copolymer of styrene sulphonic acid and/or vinyl sulphonic acid. Moreover, there may be present a polymer selected from the group of polymers and copolymers of acrylate, methacrylate and/or maleate. Such a polymer is used in an amount of from 0.5 to 10 wt.%.
The washing-active component is preferably a non-ionic surfactant, e.g., selected from the group consisting of ethylene oxide and/or propylene oxide adducts of fatty alcohols, in combination with an anionic surfactant such as dodecyl benzenesulphonate and/or a fatty acid soap. The amount of washing-active substance, i.e. the amount of anionic and non-ionic surfactant together is most preferably at least 10 wt.%, based on the weight of the detergent composition.
The detergent composition is most preferably in powdered form and obtained by spray-drying all or a portion of the components to an average particle size of from 0.1 to 2.0 mm, preferably to particles having an average size of from 0.3 to 1.4 mm. In case not all components are spray-dried, the rest of the components can be atomized onto the spray-dried granules. It is also possible, however, to mix the components in dry condition, or to spray-dry a portion and to mix the resulting granules with the rest of the components.
The overall makeup of the detergent composition according to the invention is preferably:

a. a builder system based on
- 1. at least 20 wt.% soluble silicate (based on the.detergent composition),
- 2. 5 to 20 wt.% sodium carbonate and/or sodium bicarbonate,
b. 0.5 to 10 wt.% anionic polymer
c. 5 to 20 wt.% anionic and/or non-ionic surfactant, and
d. 0.5 to 50 wt.% conventional additives.

The pH of the detergent composition according to the invention is preferably 10-12, as 1 wt.% solution in water having a hardness of 14° DH, preferably 10 to 11.
The invention will now be illustrated by some examples.

EXAMPLE 1

A powdered detergent composition having an average particle size of about 1.0 mm was manufactured by spraying the major part of the components, with the exception of the enzyme, the perfume and the perborate. These were added later. The resulting product had the following composition:

28.6 wt.%: sodium disilicate
9.0 wt.%: soda
2.4 wt.%: Sokalan CP 7 (copolymer of acrylic acid and maleic acid)
0.3 wt.%: Dequest (phosphonate)
20.0 wt.%: sodium perborate.4 aq.
5.2 wt.%: sodium soap
5.7 wt.%: sodium dodecyl benzene sulphonate
1.0 wt.%: Lutensol. 7 EO
22.6 wt.%: sodium sulphonate
4.0 wt.%: water
0.6 wt.%: carboxymethyl cellulose
0.2 wt.%: DMS-X (optically bright)
0.3 wt.%: protease
0.2 wt.%: perfume

This product was tested on laundry soiled in the household in a bundle test in comparison with the same amount (180 g) of regular main wash detergent composition on the basis of SAS (sodium aluminosilicate) and with the same amount of main wash detergent composition on the basis of STP (phosphate).
Both at 60° and at 90°C an equal primary detergency and incrustation was obtained, while at both temperatures the product according to the invention showed less redeposition.

EXAMPLE 2 and Comparative Example

Two powdered detergent compositions having an average particle size of about 1.0 mm were manufactured by spraying the major portion of the components, with the exception of the enzyme, the perfume and the perborate. These were added later. The resulting products had the composition given in Table 1. These detergent compositions were tested in order to determine the degree of incrustation. On cotton the comparative product with metasilicate showed an ash residue after clay test of 7.6%. On polyester cotton this was 3.6%. For the composition according to the invention these values were respectively 2.8% and 2.2%.

EXAMPLE 3

A compact powdered detergent composition was manufactured by mixing the components. The resulting product had the composition given in Table 2. This detergent composition was tested in order to determine the degree of incrustation. On cotton the product showed an ash residue after clay test of 1.0%. On polyester cotton this was 1.4%.

Claims

A main wash detergent composition comprising
a. a builder system based on
1. at least 20 wt.% soluble silicate (based on the detergent composition) in an Na₂O/SiO₂ ratio less than or equal to 1/2,

2. sodium carbonate and/or sodium bicarbonate

b. 0.5 to 10 wt.% anionic polymer

c. anionic and/or non-ionic surfactant, and

d. if desired, conventional additives.
A main wash detergent composition as claimed in claim 1, in which the conventional additives are selected from the group consisting of filler, bleach system, enzyme, dye, optical brightener, perfume, water, hydrotrope, fabric softener, soap, antiredeposition agent and combinations thereof.
A main wash detergent composition as claimed in claim 1 or 2, in which the soluble silicate has a solubility of at least 2 g/1 in demiwater.
A main wash detergent composition as claimed in claims 1-3, in which the soluble silicate is selected from the group consisting of disilicate, trisilicate and laminar silicate.
A main wash detergent composition as claimed in claims 1-4, which also contains a phosphonate.
A main wash detergent composition as claimed in claims 1-5, in which the anionic polymer contains sulphonate groups.
A main wash detergent composition as claimed in claim 6, in which the polymer is a polymer or copolymer of styrene sulphonic acid and/or vinyl sulphonic acid.
A main wash detergent composition as claimed in claims 1-5, in which the anionic polymer is selected from the group of polymers and copolymers of acrylate, methacrylate and/or maleate.
A main wash detergent composition as claimed in claims 1-8, in which the content of the anionic polymer ranges from 1.0 to 7 wt.%.
A main wash detergent composition as claimed in claims 1-9, in which the surfactant is a non-ionic surfactant selected from the group consisting of ethylene oxide and/or propylene oxide adducts of fatty alcohols, in combination with an anionic surfactant such as dodecyl benzene sulphonate.
A main wash detergent composition as claimed in claims 1-10, in which the builder system is based on 20 to 60 wt.% soluble silicate, 5 to 20 wt.% sodium carbonate and/or sodium bicarbonate and 0.5 to 10 wt.% anionic polymer.
A main wash detergent composition as claimed in claims 1-11, in which the content of the builder system based on the anhydrous product ranges from 25 to 90 wt.%.
A main wash detergent composition as claimed in claims 1-12, in which the content of the surfactant based on the anhydrous product ranges from 5 to 40 wt.%.
A main wash detergent composition as claimed in claims 1-13, consisting of a powdered material having an average particle size of from 0.1 to 2.0 mm.
A main wash detergent composition as claimed in claims 1-14, having a pH, as 1 wt.% solution in water having a hardness of 14° dh, of 10-12, preferably 10-11.
A main wash detergent composition as claimed in claims 1-15, in which 1 to 50 wt.% filler is present.
A main wash detergent composition as claimed in claims 1-15, in which no filler is present.