[0001] The present invention relates to a bleaching and cleaning composition, and more in
particular to a liquid thickened chlorine bleaching composition which is based on
an aqueous solution of alkali metal hypochlorite.
[0002] Aqueous solutions of an alkali metal hypochlorite are widely used as disinfectant
cleaners for lavatory pans, urinals, drains and waste pipes, but may also be employed
in the cleaning and bleaching of fabrics.
[0003] In British Patent Specification N° 1 329 086 it has been recognized that the efficiency
of such solutions is considerably increased by thickening to viscosities at which
they adhere much longer to non-horizontal surfaces, thereby enabling them to perform
their bleaching/ cleaning function before draining off.
[0004] In the British Patent 1 329 086 thickened chlorine bleaching compositions are described,
which have an active-chlorine content of 1 to 15% by weight and a thickening detergent-active
system comprising an alkali metal salt of a fully saturated C
8-C
18 fatty acid in combination with, inter alia, a trialkylamineoxide having a straight
chain C
8-C
18 alkyl group and two
Cl-
C3 groups.
[0005] In general, present-day bleaching products based on the above thickening system contain
the commercially available amineoxides derived from naturally occurring fatty acids
such as coconut acids, lauric acid and myristic acid.
[0006] It has now been found that if a substantial proportion (which will be defined below)
of the long-chain alkyl groups of the amineoxide are C
16-C
18 alkyl groups, the thickening action is significantly improved and accordingly levels
of the thickening active system may be reduced. Furthermore it has been found that,
in particular if higher proportions of amineoxide have C
18 alkyl groups, the weight ratio of the amineoxide to the co-active may be decreased,
which in general leads to a further reduction in costs.
[0007] Accordingly the present invention provides a liquid thickened chlorine bleaching
composition comprising an aqueous alkali-metal hypochlorite solution which is thickened
by means of a detergent-active mixture comprising a mono(C
8-C
18)-di(C
1-C
3) alkylamine-oxide, characterized in that at least 20% by weight of the amineoxide
component have C
16-C
18 alkyl-groups.
[0008] The thickening active system consists of at least two different detergent-active
components, one of which comprises a trialkylamineoxide having two short chain C
l-C
3 alkylgroups and a long chain C
8-C
18 alkylgroup. In order to obtain the advantages of the present invention at least 20%,
preferably 20 to 50%, and most preferably 30 to 50% by weight of the amineoxide should
contain long chain alkylgroups having 16-18 carbon atoms. Higher proportions of amineoxide
having C
18 alkyl groups have an increasing effect on the cloud point of the composition and
in general allow a reduction of the amineoxide/co-active weight ratio. Accordingly
it is preferred that in the C
16-C
18 alkylamine-oxide fraction the amount of C
18-alkyl exceeds that of C
16-alkyl.
[0009] The second detergent active component present in the thickener can be an alkalimetal
soap or mixture thereof according to British Patent Specification 1 329 086, alkalimetal
acylsarcosinates or -alkyltaurides according to British Patent Specification 1 466
560 or sugar esters according to Dutch Patent Application 7 605 328, or mixtures thereof.
Alkali metal C
10-C
18 alkylether (containing 1-10 moles of ethylene- and/or propyleneoxide) sulphates can
also be used. However, the mixtures of trialkylamineoxides and alkali metal soaps
of fully saturated C
a-C
18 fatty acids are preferred.
[0010] The thickening active system is used in an amount of 0.3-5%, preferably 0.5-3% by
weight of the final composition.
[0011] The composition may be thickened to a wide range of viscosities, preferably from
about 10 to 250 cS or even from about 30 to 150 cS as measured with a U-tube viscosimeter
at a temperature of 25°C.
[0012] The stability of the composition may be improved by the addition of a small amount,
in the order of 0.1-15%, of alkaline agents, such as for example sodium carbonate,
trisodium orthophosphate, sodium hydroxide and the like.
[0013] The alkali metal hypochlorite will generally be present in the composition in an
amount sufficient to provide from 1 to 15%, preferably 2 to 11% and most preferably
5 to 10% by weight of available chlorine on the basis of the total weight of the composition.
[0014] Although alkali metal hypochlorites are preferred, other chlorine compounds which
yield the hypochlorite ion in alkaline aqueous solution may also be used, e.g. calcium
and magnesium hypochlorite, alkali metal dichloro-isocyanurate, chloramines and the
like.
[0015] Further, the thickened chlorine bleaching compositions according to the invention
may contain small amounts of conventional additives, such as hypochlorite-soluble
and stable colorants and perfumes. Small amounts of insoluble solid particles are
also tolerable.
[0016] The compositions of the invention can be prepared in conventional ways, for example
as described in British Patent Specification 1 329 086.
[0017] The compositions of the invention are useful for all bleaching purposes, especially
for bleaching hard surfaces, such as toilets, tiles, floors, kitchen sinks, etc.,
where by their thickened nature they adhere longer to the surface than non-thickened
bleaching compositions.
[0018] The invention will be further illustrated by way of example, in which all percentages
are by weight unless otherwise indicated.
[0019] The following general composition was used in all examples:

[0020] In Table 1 comparative examples are given, illustrating for products with constant
active level the effects of varying amineoxide compositions on viscosity and cloud-
point behaviour.

[0021] In Table 2 comparative examples are given illustrating for products having the same
viscosity (~45 cS) and cloud point (~43°C) the reduction in active level for varying
amineoxide compositions.

[0022] In Table 3 comparative examples are given illustrating for products having the same
cloud point (45°C) the effect on viscosity for varying amineoxide compositions (using
mixtures of Coco-AO and Tallow-AO) and reduction in soap level.

[0023] In Table 4 comparative examples are given illustrating for products having the same
viscosity (25 cS) the reduction in active system.

[0024] Examples 20 and 21 show improved foaming behaviour.
[0025] In Table 5 comparative examples are given illustrating the effect of varying amineoxide
compositions for other co- actives.

1. A liquid thickened chlorine bleaching composition comprising, in an aqueous solution,
alkali metal hypochlorite and at least two different detergent-active components one
of which comprises a trialkylamineoxide having two short chain Cl-C3 alkyl groups and one long chain C8-C18 alkyl group, characterised in that at least 20% of the amineoxide component have a C16-C18 alkyl group.
2. A composition according to claim 1, characterised in that 20-50% by weight of the
amineoxide component have a C16- C18 alkyl group.
3. A composition according to claim 1, characterised in that 30-50% by weight of the amineoxide component have a C16- C18 alkyl group.
4. A composition according to any one of the preceding claims, characterised in that
the major part of the C16-C18 amineoxide consists of amineoxide having a C18 alkyl group.
5. A composition according to any one of the preceding claims characterised in that
the composition comprises 0.3-5% by weight of the detergent-active components, 0.1-15%
by weight of alkaline agents and sufficient alkali metal hypochlorite to provide 1-15%
by weight of available chlorine.