Note: Descriptions are shown in the official language in which they were submitted.
i~88~45 C 59~ (P~)
Low phosphate detergent cornposi-tion.
The present invention relates to de-tergent, cleaning and
blea~hin~ compositions of any type, having a low phos-
phate content.
Condensed phosphates, such as sodiumtriphosphate and
tetrasodiumpyrophosphate, have already been known and
applied as builder salts in the detergent industry for
decades.
In the last few years, however, the use of high contents
of sodiumtriphosphate has been subjected -to critical
consideration, as soluble phosphates are suspected to
accelerate the eutrophication of surface waters. Conse-
quently, the detergent industry has made efforts to find
substitutes for the phosphate builder salts, and actually
a great many phosphate substitutes have been suggested
which can wholly or partly replace sodium triphosphate.
The use of such partial substitutes, however, may involve
certain drawbacks, such e.g. increased incrustation.
It was therefore an object of the invention to provide a
detergent composition with a reduced phosphate content,
which nevertheless has an incrustation behaviour corre-
sponding in type and level to that of a detergent compo-
sition having the usual high tripolyp~osphate content.This object was a-ttained by the finding that a detergent
composition comprising a builder mixture of from 1 - 5 wt~
of an alkalimetal orthophospha-te and from 3 - 20 wt~,
preferably from 5 - 15 wt%, of an alkalimetal salt of
nitrilo-triacetic acid shows such an incrustation behav-
iour. The detergent composition has a phosphate content of
1% or less. The invention therefore relates to a deter-
gen-t, cleaniny and bleaching composition havins a phosphor
content equivalen-t to or lower -than 1%, which in addition
to detergen-t-active substances, comprises builder salts,
~68~5 C 599 (R)
and is characterized in tha-t it contains from 1 to 5
percent by weight of an alkalimetal orthopho.sphate and
from 3 to 20, preferably from 5 to 15 percent by weight,
of an alkalimetal salt of nitrilotriacetic acid.
The alkalimetal orthophosphate can be a mono-, di- or tri-
orthophosphate, trisodi~northophosphate (TSOP) being pre-
ferred. The nitrilotriacetic acid alkalimetal salt is
preferably the trisodium salt (~TA). Both salts can be
used either as an anhydrous salt or as a sal-t containing
water of crystallization.
It has appeared that ~he ratio of the nitrilotriacetic
salt (NTA) to the alkalimetal orthophosphate (TSOP) in-
fluences the incrustation behaviour to a certain extent;this ratio is preferred to be 1 or higher, preferably
above 2, although good results can also be obtained with
lower ratios.
Although very qood effects can already be achieved with
~he TSOP/NTA mixture according to the invention, it was
found that the incrustation behaviour can be further im-
proved by additionally incorporating a polymeric electro-
lyte into the detergent composition. Such polymeric elec-
trolytes are Xnown per se, typical examples being the
. .
alkalimetal- or ammonium-salts of homo- and co-polymers of
acrylic acid or substituted acrylic acids, such as sodium
polyacrylate, sodium copolymethacrylamide/acrylate and
sodium polyalpha-hydroxyacrylate, salts of copolymers of
maleic acid anhydride and ethylene, acrylic acid, vinyl-
methylether, diisobutylene, allylacetate or styrene, par-
ticularly the 1:1 copolymers, which optionally may be
partly esterified. Such copolymers preferably have a low
molecular weight, for example from 1,000 to 50,000. Other
suitable polymeric electrolytes are the alXa~imetal salts
of polymaleic acid, polyitaconic acid, polyasparaginic
C 5g9 (R)
~ ~8~45
acid, ether polycarboxylic acid, such as sodiwn glycol-
ate-malona~e, as well as the compounds accordiny to
European patent applications 0009953 and 0009954, laid
open to public inspection. Generally, the polymeric
electrolytes are used in an arnount of from 0.1 to 5
percent by weight, preferably from 0.3 to 2 percent by
weight.
The binary or ternary mix-ture according to the invention
can be used in all types of detergent compositions. Thus,
the combination according -to the invention can be used in
detergent compositions containing an anionic, a nonionic,
a cationic synthetic detergent compound or a soap or mix-
tures thereof, and which additionally comprise the normal
additives and/or auxiliary materials for detergent compo-
sitions. By the term soap is to be understood an alkali-
metal-, e.g. sodium- or potassium-salt, of a (C10-C24)-
carboxylic acicl.
The detergent compositions essentially comprise one or more
anionic, nonionic, amphoteric or zwitterionic, detergent-
active compounds, or mixtures thereof, and generally
builder salts.
The synthetic detergen-t-active compounds which can be used
according to the invention are preferably anionic deter-
gent-active compounds that are readily available and rela-
tively cheap, as well as mixtures thereof. Normally these
compounds are water-soluble alkalimetal salts of organic
sulphonates or sulphuric acid esters having alkyl radicals
with about 8 to 22 carbon atoms. Examples of such synthetic
anionic detergent-active compounds are sodium- or potassium-
sulphuric acid esters, particularly those which can be pre-
pared by sulphating C8-Cl~-fatty alcohols that are ob-
tained by reduction of fatty acids derived Erom tallow orcoconut oil, or synthetic alcohols, which are obtained e.~.
C 59g (R)
~ ~8~45
by Oxo-syrlthesis or Ziegler-synthesis; sodium- or potassium-
alkyl (c9-c20)-benzenesulphonates, particularly sodium-
lin ~Sec--alkyl (clo-cl5)-benzenesulphonates; sodium- or
potassium-alkyl-polyglycolether sulphuric acid esters, par-
ticularly from ethers of higher alcohols which are obtainedfrom tallow or coconut oil, or of synthetic higher alcohols;
sodium- or potassium-salts of fatty acid monoglyceride-sul-
phates or -sulphonates; reaction products of fatty acids,
e.g. tallow of coconut fatty acid, with isethionic acid and
neutralised with sodium- or po-tassium-hydroxide; sodium- and
potassium-salts o F fatty acid methyl taurides; alkane mono-
sulphonates, such as those which are obtained by reaction of
C8- to C20-alpha-olefins with sodium hydrogensulphite or
by reaction of paraffins with SO2 and C12 or 2 and subse-
quent hydrolysis with sodium- or potassium-hydroxide, as
well as olefinsulphonates, which term is meant to denote
the material which is obtained by reaction of olefins,
particularly alpha-olefins, with SO3 and subsequent hydro-
lisation and neutralisation.
Nonionic detergent-active compounds can also be used.
Examples are the reaction products o~ alkylene oxide,
particularly ethylene oxide and/or propylene oxide, with
alkyl (C6-C12)-phenols, C8- to C20-alkanols, fatty acid
amides, in which in general from 5 to 30 ethylene units
are present in the molecule, block polymerisates from pro-
pylene oxide and ethylene oxide, condensation products of
ethylene oxide with reaction products from propylene oxide
with ethylene diamine, etc. Other nonionic detergent-active
compounds comprise long-chain tertlary amine- or phosphine
oxides and dialkyl sulphoxides.
Mixtures of detergent-active compounds, e.g. mixed anionic
and mixed anionic and nonionic compounds can be used in the
detergent compositions, particularly to impart controlled
C 599 (R)
~88~4~
- 5
low-sudsing properties. This is particularly advantageous
for compositions that are to be used in suds-intolerant,
automatic washing machines. Mixtures of amine oxides and
ethoxylated, noniorlic compounds can also be advantageous.
Many sui-table detergent-active cornpounds are commercially
available and have been desc~ibed in the literature, e.g.
in "Surface Ac-tive Detergents" o~ Schwartz, Perry and
Berch.
Mixtures of amphoteric and zwitterionic detergent-active
compounds can also be used in the compositions o~ the in-
vention; normally however this is not desirable in view of
their relatively high cost. In case any amphoteric or
zwitterionic compounds are used, this is generally done in
small amounts in compositions based on the more commonly
used anionic or nonionic detergent-active compounds.
Depending on the properties desired, the amount in which
the synthetic detergent-active compound(s) is/are used
generally ranges from about 5 to about 50 percent by
weight, calculated on the compositions. The detergent
compositions can optionally contain further inorganic
and/or organic builders, but no condensed phosphate
builders. Examples of such builders are citrates, oxi-
dised starch- and cellulose derivatives, particularly
those with dicarboxyl radicals, sodiumalkenyl-(Clo-C20)-
succinates, sodiumsulpho~fatty acids, alkalimetalcarbon-
ates, sodiumaluminosilicates, carboxymethyloxysuccinates,
etc. m ese builders can be incorporated in minor amounts.
Other conventional materials can be present in -the de~ergent
compositions according to the invention, e.g. anti-deposition
agents, hydrotropes, corrosion inhibitors, dyes, perfumes,
fillers, fluorescers, enzymes, suds~boosters, suds-depressors,
C 599 ~R)
B8~
germicides, anti-tarnishing agents, fabric softeners,
chlorine-releasing agents, oxygen-releasing bleaching
agents, such as sodium-perborate or -percarbonate with or
without peracid precursors, buffers and the like. The
remainder of the detergent compositions consists of watçr,
e.g. ranging from 5 to 15% in the powdered detergent com-
positions.
The compositions according to the inven-tion can be used
for domestic products and industrial products, as well as
for machine dishwashing agen-ts, household cleaners e-tc.
The detergent compositions according to the invention can
have any customary forl-n for such compositions, such as
powder, pellets, flakes, bars, tablets, noodles, liquids,
pastes and the like. The detergent compositions are pre-
pared and applied in the conven-tional way, e.g. in the
case of powdered detergent coMpositions they can be made
by spray-drying aqueous slurries of the detergent ingre-
dients or by dry-mixing processes, in which also the NTA
can be added to the base powder in a secondary step. The
invention will be further illustrated by means of the
following Examples, in which percentages are by weight,
calculated on -the finished detergent composition.
The experiments were carried out in an Atlas-Laundero-
meter, in which water of 23 GH was used. Ten repeated
washes were carxied out at 95C, using the following
base formulation:
C 599 (R)
5~5
w~ . ~
sodium dodecyl benzenesulphonate6.0
C12-~15-P-alcoholr condensed with
15 mol ~04.0
sodium-C16-C22-fatty acid soap 3.0
5 carboxymethylcellulose 1.0
alkaline waterglass (2/1) 6.0
sodium perborate 22.0
sodium sulphate ) taking into account
water, additives ) NTA, TSOP and sodium
10 polyacryIate to 100.0
Varying amounts of NTA and TSOP were incorporated in this
formulation, and the ash contents o~ the 'IKrefelder'' cot-
ton test fabrics washed with these formulations were de-
termined and compared with the ash content of the testfabric washed with the control composition. A dosing of 6,
8 or 10 g/l of the formulation in water was applied. The
greying degrees were also determined and compared; for this
purpose an Elrephometer with Xenon-lamp at 620 nm was used.
The fol]owing results were obtair.ed:
Formulations with:
STP (~) 30 - - - -
NTA (%) - 16.8 16.8 14.0 14.0
25 TSOP (~) - 2 2 4 4
sodium polyacrylate
(mol.~. 25000 (%) - 0 1 0
Ratio NTA:TSOP 8.4 8.4 3.5 3.5
Ash content
30 6 g/l 1.01.1 0.5 2.0 1.2
8 ~/1 0.70.1 0.1 0.4 0.2
10 g/l 0.1 0.1 0.1 0.1 0.1
C 59~ ( P'~
~ 854~
Greying
6 g/l 16.5 16.2 12.8 16.614.6
8 y/l 13.9 6.9 6.2 12.9 9~6
g/l 8.6 6.0 ~.9 7.5 5.3
