CA1102654A

CA1102654A - Silicic acid detergent product for microdeposition of silicic acid on textiles

Info

Publication number: CA1102654A
Application number: CA283,443A
Authority: CA
Inventors: Hans Johansson; Olof Sunden; Hdkan B. Ahlberg; Per-Arne I. Karlsson
Original assignee: Elektrokemiska AB
Current assignee: Elektrokemiska AB
Priority date: 1976-08-02
Filing date: 1977-07-25
Publication date: 1981-06-09
Also published as: FR2360661A1; DE2732752A1; DK343377A; IT1086343B; FR2360661B1; JPS5341311A; ES461232A1; GB1585805A; NL7708536A

Abstract

Abstract of the Disclosure.
The disclosure relates generally to the detergent art and more specifically to a silicic acid detergent product for the microdeposition of silicic acid on textiles. The product comprises essentially an adduct (hydrogen bond) compound of oligomer and/or polymer silicic acid with polyethylene oxide compounds together with alkali, M2O, where M is selected from the group consisting of Na, K, Li and quaternary ammonium radi-cal, amounting to a molar ratio SiO2:M2O > 4, or preferably 6-100, said product being physically or colloidally soluble in laundry medium inside a pH of 8-12, in which medium it serves as a microdepositor for silicic acid on laundry textiles.

Description

6~ ~
- ~ This invention refers to a group of silicic acid compounds to be used in laundering and with the specific property of depositing microamounts of silicic acid on textile fibers during laundering, by which deposition process the redeposition of soil from the laundry medium to the textiles is prevented. Hence, the invention is of special importance for laundering and the treatment of polyester and cotton textiles which usually show a decreasing brightness with repeated laundering due to redeposition of soil from the laundry medium.
Thus, a basic object of the present invention is to realize a detergent component which prevents soil redeposition and progressive greying of polyester fibers and textiles of such fibers.
;~ A further essential object of the present invention is to provide a detergent component based on , silicic acid which is usable at a pH of below 10.5 in large concentrations and which functions as a builder and - -;~ ~ , . . .
complexing agent such that the polyphosphate component can be i~
reduced in the detergent composition.
It is well known that soluble alkali silicates such as sodium metasilicate and waterglasses are used as ;' components in washing detergents. Some of their drawbacks are a very high alkalinity and the risk of massive and uncontrolled silica precipitation on textiles if pH
decreases which makes them hard, brittle and grey due to preC\ ~ Q`+Id~ cl~QC~ .
the inclusion of~soil.
The present invention refers to a new group of silicic acid complexes which does not form any dangerous precipitate, even if pH decreases to 8, which is a very low pH for detergent compositions. Within the pH range of from 8 to 12 and preferably from 8 to 10.5 these new compounds deposit a very small amount, a microamount, of 6~, ~silicic acid or silicic acid compounds Oll fibers such as -polyester and cotton. This microamount is far from dangerous to the textiles and cannct be measured as an increased ash content, only qualitatively detected by electron initiated x-ray emission in an electron microscope.
The degree of deposition is consequently very difficult to estimate, but an increased ash content can be analyzed down to 0.01% and because this deposition is even lower it may be estimated to about 0.001% or 10 ppm of the fiber weight.
For the present discussion, this small amount o silicic acid deposition will be called "microdeposition", and the compounds responsible for this microdeposition "microdepositors". This microdeposition is highly advantageous with respect to the prevention o~ soil redeposition on textiles, , ' r ~ because it induces a strong negative electrical charge to .~; .
the fibers even when positive ions such as Ca , Mg +

; are present.
;
Microdepositing silicic acid compounds or "microdepositors" are adduct (hydrogen bond) compounds of oligomer and/or polymer silicic acid and ethylene oxide products with a critical and limited amount of alkali .
corresponding to a molar ratio SiO2:M20~ 4 or preferably 6-100, in which formula M20 is Na20, K20, Li20 or the corresponding "oxide" of quaternary ammonium compounds. It should be ~` emphasized that this small content of alkali is not sufficient to give a water soluble silicate such as waterglass. The highest commercia] ratio in produc-ts available on the market is about SiO2:M20 = 3.5, and ratios above that limit mostly give gels which are difficult to handle. For solubilities of ratios above 4 specific silica structures are required The ethylene oxide products used for production of the adduct (hydrogen bond) silicic acid compounds can be the simple polyethylene glycols, and preferably those with 10-100 .~ .
:~

`, ethylene oxide units in the molecule. From the economic point of view, it is advantageous to use polyethylene oxide products which are of great value per se in laundering, for ins-tance the nonionic tensides achieved by reacting nonyl phenols, fatty alcohols, fatty amines (saturated and unsaturated) etc. with ethylene oxide. For this special purpose tenside products with ~ up to 30 ethylene oxide units can be used and 10-20 units ,~ in the molecule are to be preferre,d, due to the solubility properties of the silicic acid adduct.
The molar ratio of Si02:-C~2CH20- is not very critical for the function of the product as "microdepositor"
of silicic acid but it is important for the efficient use of the silicic component. The ratio SiO2:-CH2CH20- can be 1 and higher but preferably between 1.5 50. At the higher ratios some silicic acid will remain as solid particles or suspended particles in the laundry medium, but will not precipitate or attach to the textile material in case the silicic acid is of specific gel type, preferred here and described below.
, It is known that hydrogen bond adducts ~complexes) between soluble silicic acid (oligomers) and polyethylene oxide products occur on the acidic side. Hence a solution of acidic oligomer silicic acid gives a precipitation of a hydrogen bond complex with soluble polyethylene oxide compounds.
The new interesting discovery is that these hydrogen bond ~ ~ complexes also form specific complexes on the alkaline side, `~ which have remarkable solubility properties in spite of a low alkali~content,~quite different from those of~ only-silicic acid or only polyethylene oxide compound, especially in the pH
.~ , , ~,, range of 8-10.5. Below pH 8 they precipitate as a homogeneous ,~ compound, which can be redissolved, if the pH is increased to 8.

Above pH 12 the compounds rapidly disintegrate to common soluble silicates and polyethylene oxide compounds. Between pH 10.5 5i4 and 12, thi~ disintegration proceeds more slowly, for which reason laundering can be perf`ormed up to a pH of 11.0 11.5 with some retained microdeposition of silicic acid on the textile material.
The most important step in producing a silicic depositor compound is the preparation of the silicic acid component itself. Even if soluble silicates such as waterglass are the raw materials for the desired silicic acid component, it is hardly possible to synthetize the depositor direct from soluble silicates, especially not when a dry detergent is required by the market, The best way is to start from a solid but active silicic acid polymer. Some precipitated silica trade marks can be used as well as pyrogenic silica (from silicium tetra chloride) but the final product achieved is inferior compared with the product achieved with a solid silica gel having a BET-surface of at least 200 m /gO
Such a solid silica gel can be polycondensated and precipitated preferably in the presence of the polyethylene oxide component from a solution of oligomer silicic acid at a pH below 9 and preferably below 6 and even down to 2-4.
The BET-surface achieved on the silica gel depends very much on the pH under the precipitation (and polycondensation stage) which is indicated in the following - table: -pH BET-surface m /g ~25 ~ 2 700 -`
The solid silicic acid component can be polycondensa$ed and precipitated in the presence o~ the polyethylene oxide compound or this can be added later ~or instance in connection with $he alkalization process.

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Suitable steps of production are the following:
1. Waterglass is rapidly acidified on being poured in-to sulphuric acid to ~orm soluble oligomer silicic acid.
2a. When the mixture has reached a pH of 2-3 the poly-ethylene oxide component is added J which will cause the formation of a second liquid phase which solidifies during the polyconden-satlon process to a compound gel comprising polysilicic acid and the polyethylene oxide compound. Polycondensation may be per-formed in connection with spray-drying.
2b. The soluble oligomer silicic acid ca~ also be poly-condensated alone without the polyethylene oxide component, but it is then more necessary to increase the pH and the temperature to increase the rate of polycondensation The solid gel has to be broken up to a slurry and then the polyethylene oxide compon-ent should be added.
2c. To the soluble oligomer silicic acid may also be added a soluble Al-sulfate or other Al-salt in order to incorpor-ate A1203 in the depositor product, which seems to increase its efficiency. The ratio SiO2:A1203 should be above 2 and preferably between 4 and 40. Also in this case the polyethylene oxide com-ponent can be added before or after solidification.
3 The intermediate product can, if desired, be washed free of the sodium sulfa$e formed, and it should be dried to a water content of about 5-20%.
~` 4. The final step, the alkalization, can be performed ; by grinding the intermediate product with sodium hydro~ide, meta-silicate or waterglass or any other strongly alkaline salt of weak acids, e g. perborates and borates at the alkali ratio specified.
~ It is important that some moisture be present during this alkali-`~ 30 zation step. The alkalization process can preferably be per~ormed ~` simultaneously with the final compounding of the dete:rgent compo-sition utilizing the s-trong alkalinity of other composition ingre-dients like perborate, borate and trisodiumphosphotate.

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The use of the speclfic silicic acid component ac-cording to 1 and 2 above, offers the advantage that the silicic acid component can be in surplus o~ the other compounds, without precipitation and attaching the textile material, ~hen other types of sillca (precipitated or pyrogenic) are used the sur-plus of "unreacted" silica will directly attach to the textiles and increase the ash content, With increasing BET-surface and with the addition of Al-salts to the oligomer silicic acid, the ion exchange capacity o~ the product increases from 90 to 120 mg CaO/G product which is important when hard waters are used for laundering, The invention is particularly directed toward a silicic acid product to be used for laundry purposes with the property of depositing microamounts of silicic acid on cellulose ~ and polyester ~ibers o-f laundry textiles and thereby preventing ; redepositioD of soil from the laundry medium on the textile materials, The silicic acid product comprises an adduct (Hydrogen bond) compound of oligomer and/or polymer silicic acid with polyethylene oxide compounds together with alkali, M2O, where M is selected from the group consisting of Na, K, Li and quaternary ammonium radical, amounting to a molar ratio SiO2:M2O~ 4, The product is physically or colloidally soluble in a laundry medium inside a pH of 8-12, in which medium it serves as a microdepositor for silicic acid on laundry textiles, The iDVention is also directed toward a process for manufacturing a silicic acid product comprising the steps, per~ormed between 0-100C in the presence of water, of: pre-- paring a solid silicic acid compound ~Gel) with a B~T-sur~ace o~ more than 200 m2/g by polycondensation and/or precipitation o~ a soluble (oligomer) silicic acid or alkali silicate by .~ .
performing the polycondensation/precipitation at a pH below 9; reacting the resulting solid silicic acid compound with a .

polyethylene oxide product, after its solidiflcation or during the polycondensation/precipltation process; and re-acting the resulting adduct compound between silicic acid and !::
polyethylene oxide product with alkali, M20, in an amount corresponding to a molar ratio SiO2/M20 of at least 4 Example I
A solid polyethylene glycol-, "Modopeg* 4000" with high molecular weight was dissolved in water to a 15% solution Standard waterglass available on the market containing about 10 360 g SiO2 per litre was diluted to twice the volume and 200 ml of this mixture was batched, under intensive agitation and in an extremely fine jet to 100 ml 4- normal sulphuric acid. Once all of the waterglass had been consumed, the pH of the mixture was determined at 1.4. To this mixture, which thus contained about 36 g SiO2 in the form of acidic oligomer silicic acid (solution) was added 100 ml of the above-disclosed Modopeg solution which thus corresponds to 15 g of high molecular poly-ethylene glycol.
./ Immediately `after the mixture, which was carried out : `
~'`,5 20 at from 20 to 30C, the solution was clouded and a separate ~','f liquid phase which was heavier than the aqueous phase separated out. After agitation for 3 h, the separated liquid phase as-sumed a solid crystalline-like structure This was subjected ~. .
5;i. to wet milling, and after 4 h, the "crystals" were filtered off, washed and dried. The filtrate was checked such that it showed further clouding on the addition o~ more Modopeg solution, ' "

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` * Trade Mark -6a-n ~ t which showed that excess oligomer silicic acid was present, The filtered-off deposit, dried at a tempexature of at most 80C, weighed 46 g, which corresponds to a silicic acid absorption of 31 g (slightly in excess of 1/2 mol) of the batched 15 g Modopeg (1~3 equivalent weight of ethylene oxide), This, like silica and carbon analysis, showed that each ethylene oxide group had absorbed 1,56 mol silicic acid (SiO2), The dried powder was milled in a mortar and rapidly mixed with 17 ml 10-normal NaOH
(slightly in excess of 1/6 mol), After 30 s the mixture assumed a pasty consistency~ but hardened to a solid crystalline substance within 3 minutes, This proved to be of unrestricted storage life and was to 95% soluble in 60C
warm water, It is possible to obtain solutions with up to 15% dry content, These have a pH of 11, whereas 1%
solutions display a pH of 9,6, ; In the acid addition to a 1% solution, ethoxy silicate at pH 7-8 was deposited, The deposition appeared ;.
to be total at pH 3-5, The deposition is easily filtered and easily dried, It gives a ratio C/Si which suggests that each ethoxy group binds 1,43 SiO2 units. The product ; obtained was examined as a detergent component and it proved that the product prevented greying simultaneously as silicic acid was deposited, ~- Example 2 ~ The same oligomer silicic acid as in Example 1 ;~ was prepared anew and batched to a 10% solution of oc-tadecyl ;~ alcohol, reacted with 18 mol ethylene oxide, In this case use was made of 200 ml of 10% tenside solution (20 g) ;3~ together with 300 ml acidic oligomer silicic acid, containing 120 g SiO2 per litre ~36 g), The deposition which was first obtained was more waxy and assumed, after 2 h, a hard crystalline character, After 4 h, it was filtered off and washed. It was checked that -the filtrate contained excess oligomer silicic acid. After drying, 48 g o-f the product was obtained. This weight, together with C/Si analysis, showed that each ethylene oxide group had reacted with 1.44 mol silicic acid.
The product which contained slightly less than 1/2 mol SiO2, was alkalized with 15 ml 10-n NaO~. The product thus obtained was soluble to from 96 to 97% in warm water and it was possible to obtain a 12~o solution thereof. In the 1~ solution, the pH was 9.1. On -the addition of sulphuric acid to a 1% solution, the product precipitated at pH 7.2. The deposition seemed to be finely crystalline and could easily be filtered ~nd washed. The thus-obtained secondary deposition had a C/Si ratio corresponding to 1.56 Si02 per mol ethylene oxide.
The product which was obtained directly after the alkalization was used as a detergent component in a detergent mixture of low phosphate content, This mixture ~O was used for washing polyester fabric 10 times. The results were striking, inasmuch as the polyester -fibers did not grey in comparison with the case when washed in a washing ; solution which contained a corresponding detergent composition b~t wi-thout the ethoxy silicic acid adduct, A scanning analysis with electron initiation of the .
surface of the washed polyester fibers clearly showed a deposition of silica on the samples which were washed when the ethoxy silicic acid adduct was present.
Exam~e 3 ~` A polysilicic acid was prepared. As starting materials, use was made of a waterglass solution consisting of equal par-ts of water and waterglass with a ratio SiO2:Na20 of 3,3~ 400 par-ts by volume of the waterglass solutlon ~ . ' were batched in the form of fine jets to 160 parts by volume 2.5 molar sulphuric acid under intensive agitation, The thus-obtained solution of oligomer silicic acid was adjusted with NaOH to pH 2,5. This solution was then mixed with 50 parts by volume of a non-ionactive tenside which consi.sted of a 10% nonylphenol polyglycolether :solution (16 E0). Air was then whisked into the tenside-containing solution of oligomer silicic acid by means of an extremely high-speed double agitator and the temperature was raised to 60C, $he silicic acid polycondensing to a solid gel. The -thus-obtained solid gel was dried in ~:
a drumdrier at 110C to a residual moisture content of about 20% and was then subjec-ted to comminutio.n in a : pinned disc mill to a particle size of from 1 to 1000 ~.
Example 4 -The same procedure i.s here applied as in Example 3, apart from that the solution of oligomer silicic acid, after the addition of non-ionactive tenside, was not foamed by ~: whisking but instead introduced into a spray-dryer (Niro Atomizer). In the treatment in the spray-dryer, the solution of oligomer silicic acid was atomized and given highly ;~ voluminous form, The temperature in the air entering the spray-dryer was about 320C and the temperature of the . ~ exhaust air was about 130C. Because of the high temperature prevailing in the spray-dryer, the silicic acid solution , ~
gelled and a solid, polycondensed silicic acid in voluminous ~; pulverulent form was obtainedO The particle size of the ; thus-obtained polysilicic acid was within the order of magnitude.of from 1 to 1000 ~ and no further comminution was necessary.
Thus, the use of a spray dryer creates a simplified process in which the realization of voluminous form, polycondensation, drying and comminution take plac~e, as i$

were, in the same operation.
The acidic product achieved can be used directly as additive to the detergent composition provlded that the required alkali 1s supplied together with other ingredients like strongly alkaline phosphates and perborates.
E~ample_5 In order to clarify the greying effects and ash contents in the use of conventional detergents as compared with the case involving detergents containing polysilicic acid with a large BET- `~
surface of more than 200 mZ/g washing experiments were carried out with the help of a terg-0-Tometer (a laboratory washing machine from the United States Testing Company Inc.). The greying of the wash was determined by reflexion measurement (Elrepho) be~ore the washing experiments and`after ten washes. The ash content of the wash after the wash experiments were determined in accordance with SIS 87 21 Ol.
The conditions in the washing experiments were as follows:
Temperature: 60C `
. Water hardness: 15dH
20 Dosage: 5 g/l Time: 35 min Speed: lO0 cycles/min Amount o-f soili~g: 0.4 g/l air-filter dust and -i l g/l synthetic skin grease Number of washes: lO
Test fabrics: 100% cotton, bleached (WFK test fabric) lG0% polyester tTerylene ~ , from ICI) ~; Polyester/cotton 65/35 ~"Hot-box', commercial fabric~
30 Rinsing: under cold running water `
,~
Detergent: As the detergent base use was made of Test Detergent A according to Swedish Standard SIS 18 2410 with the following components:

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Detergent A: Dodecylbenzene sulphonate 100% 5%

Tallow fat alcohol, 50 EO5%

Soap, tallow type, 100% 4%

Pentasodium triphosphate (Na5P3010~ 30~O

~ Waterglass (Na2O.3~2SiO2.4H20) 5%

; Soda, calcined (Na2C03) 5%

Na-CMC, 100% 1%

Magnesium silicate (MgSiO3) 1%

- EDTA-Na4, 100% ` 0.2%

Sodium sulphate, calcined, 100%
Trisodium phosphate (Na3P04.12H20) 10%
I
~~ Sodium perborate (NaB03.4H20) 25%

. Water and salts from dodecylbenzene sulphonate, soap, waterglass, Na-CMC
and EDTA-Na~ to 100%

Detergent B: as per detergent A, wherein 5% of trisodium phosphate (Na3P04.12H2O) ~ -were replaced by the product according to the present invention manufactured in Example 3.

, The results are accounted for 1n Table 1.

, TABLE 1 ,,,: ' ,:
~;; Polyester/Cotton ~;100% Polyest~r 65/35 _ 100% Cotton Greying, Greying, Greying, units units units Ash-content Detergent Ash-content Ash-content greyer ~% greyer % greyer %
~; A 41 1.43 13 0.80 14 0.24 B 26 0.78 lQ 0.61 16 0.26 It is apparent from Table 1 that detergent B which was based on the polysilicic acid according to the invention, resulted in a marked reduction of the greying and ash-content in the washing o-f polyester material. Also in the washin~g of mixed ma-terial of polyester/cotton, a reduced greying and ash-content were obtained, whereas the results in washing ~cotton material were comparable with those obtained by means , ' .
. 11 ' ~' of conventional detergent, Example 6 A commercial washing powder known as VIA, part No,01311, was tested in relation to a washing powder containing the acidic compound according to Example 4 and with the -following composition:
The sillcic acid product of ~x. 4: 5 %
Soda: 5 %
Sodium sulphate 32 %
Non-ionic tenside 8 %
10 Tallow soap ~ %
Magnesium silicate 0.5%
Sodium perborate 20 %
CMC o 5%
~ Sodium tripolyphosphate 25 %
," 100 %
The test procedure was as follows:
Temperature: 60C
Water hardness: 15C
"; Programme: normal coloureds Dosage: 90 g per wash (15 1 of water) . Soil loading: one cloth piece with 2.5 ml o-f used engine oil ~ one cloth piece with 2.5 ml of coffee :~. one cloth piece with 2.5 ml o~ tea one cloth piece with 1 g of mustard, 1 g of ketchup, 08.2 g of synthetic skin grease and 0.18 g or air filter dust Weight loading: 2 kg of towels Test fabrics: 100% polyester, gabardine with 65/35%
polyester/cotton from EMPA (Eidgen-~ssische Materialpr~fungs- und Versuch-sanstalt) i~ - 12 -Results after 10 washing cycles are illustrated in Table 2:

Polyester 100% Polyester/Cotton 65/35 Products Greyingl) Ash Content2) Greyingl) Ash Content2) Commercial washing powder 44 1.51% 10 0.55%
Washing powder with product ac-cording to Ex. 4 22 0.62% 6 0045%
__ _ . _ ;
1) Greying is specified in units o~ greyness above the initial value and determined by means o~ reflection ~ measurement (Elrepho), .~ 2) As per Swedish S-tandard SIS 872101.
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xample 7 In order to establish the washing e~fect with respect to greying and ash-content in -the washing o~ soiled textiles using conven-tional detergent and detergent containing polysilicic acid according to the present invention t washing experiments were carried out in a normal domestic washing machine, Greying and ash-content were determined in the manner disclosed in Example 5. The experiment conditions .. were as ~ollows:
Temperature: 60C
.~ Water hardness: 15dH
~; Dosage: 100 g/wash = 15 litres o~ water :
:. Rinsing: 4 times with 30 litres of water/time Amount of soiling: 2 cloth pieces 20 x 40 cm were soiled in the washing machine at 90C with 3 g Flammouss ~carbon black) and 0.6 g black iron oxide.

.' 1 cloth piece smeared with 2.5 ml used ,~: ` motor oil ~,o 1 cloth piece smeared with 2.5 ml coffee . 1 cloth piece smeared with 2.5 ml tea 1 cloth piece smeared with 1 g mustard, ; 1 g ketchup as well as 1 g synthetic skin grease and air-filter dust in the ratio 9:2.
Number of washes: 10 Test fabrics: 100% cotton, bleached (Testfabric International) 100% polyester (Terylenè ~ from ICI~
Polyester/cotton 65/35 ("Hot-box", ; 30 commercial fabric).
Detergent: As detergent base 9 use was made of Test Detergent A according to Swedish Standard SIS 18 24 10 as described in Example 4, Detergent A: Test detergent A

Detergent E: as per detergent A, wherein 5% of the tri-sodium phosphate (Na3P04.12H20) were re-placed by the product according to the pre-sent invention.
The results are accounted for in Table 3:
TAB~E 3 , . .
100% Polyester Polyester/Cotton 100% Cotton ;.

-~Greying, Ash- Greying, Ash- Greying, Ash-Detergent units content units content units con-tent 10 greyer % greyer %greyer % ~ -A22 1.09 5.4 0~782.7 0,42 E5 0069 5.1 0.802.9 0.48 ~ ' --; It is apparent ~rom Table 3 tha-t the detergent which con-tained polysilicic acid according to the present invention gave ; an extremely marked reduction in greying and ash-content as com-pared with the conventional detergent in the washing of polyester :-material, whereas the result in the washing of mixed material of ; polyester/cotton and pure cotton was comparable with that obtained with the conventional test detergent.
As was mentioned b-y way oE introduction, the polysilicic acid according to the present invention cannot only be used as a detergent component but also as sorption agents and carriers for different subjects. Thus, the polysilicic acid according to the present invention displays a considerable capacity as a drying agent and as an absorbing agent/ion exchanger. It is of particu-lar interest that this acid has an abnormally high absorption ca-pacity for certain substances and in particular base substances.
It should finally be emphasized that silicic acid de-positors according to this invention may comprise physically so-luble ingredients and colloidally soluble ingredients which are both efEicient from the silicic acid mlcrodepositlon poin-t of view. The presence o-E sal~s such as sodium sulfa-te depresses the '~?~

solubility but not the microdeposition power, which may be of advantage.
Comprehensive tests have shown that polyester and cot-ton textiles which have been washed with these depositor com-pounds in the detergent formulation have shown very little loss of brightness during 20 washing cycles, while washing without these depositors shows the very well-known loss of brightness . already after few washings. In all cases when brigh-tness has been retained, the presence of Si can be cletected on the fibers by electron initiated X-ray analyzing.

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Claims

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. A silicic acid product to be used for laundry pur-poses with the property of depositing microamounts of silicic acid on cellulose and polyester fibers of laundry textiles and thereby preventing redeposition of soil from the laundry medium on the textile materials, said silicic acid product comprising an adduct (Hydrogen bond) compound of oligomer and/or polymer silicic acid with polyethylene oxide compounds together with alkali, M2O, where M is selected from the group consisting of Na, K, Li and quaternary ammonium radical, amounting to a molar ratio SiO2:M2O>4, said product being physically or colloidally soluble in laundry medium inside a pH of 8-12, in which medium it serves as a microdepositor for silicic acid on laundry textiles.

2. The silicic acid product according to Claim 1, wherein the polyethylene oxide compound consists of a polyethylene glycol with up to 100 units of ethylene oxide.

3. The silicic acid product according to Claim 1, wherein the polyethylene oxide compound consists of ethylene oxide tensides, with radicals such as nonylphenyl, dodecyl, octadecyl or any other radical originating from saturated or unsaturated fatty alcohols or amines, and with 1-30 ethylene oxide units in the molecule, preferably 10-20.

4. The silicic acid product according to any of Claims 1-3, wherein the molar ratio of SiO2:M2O is between 6-100.

5. The silicic acid product according to any of Claims 1-3, wherein the product is dissolved and utilized in a laundry medium within a pH range of 8-10,5.

6. The silicic acid product according to any of Claims 1-3, wherein the ethylene oxide compound amounts to a molecular ratio SiO2:-CH2CH2O- above 1.0, between 1.5-50.

7. The silicic acid product according to any of Claims 1-3, wherein the silicic acid component also comprises aluminium oxide to an amount corresponding to a molar ratio SiO2:Al2O3 of between 2 and 40.

8. The silicic acid product according to any of Claims 1-3, mixed with sodium sulfate and other detergent builders.

9. A process for manufacturing a silicic acid product comprising the following steps, performed between 0-100°C in the presence of water, preparing a solid silicic acid compound (Gel) with a BET-surface of more than 200 m2/g by polycondensation and/
or precipitation of a soluble (oligomer) silicic acid or alkali silicate by performing the polycondensation/precipitation at a pH below 9, reacting the resulting solid silicic acid compound with a polyethylene oxide product, after its solidification or during the polycondensation/precipitation process, reacting the resulting adduct compound between silicic acid and polyethylene oxide product with alkali, M2O, in an amount corresponding to a molar ratio SiO2/M2O is at least 4.

10. The process according to Claim 9, including pre-paring a solid silicic acid compound and simultaneously reacting the silicic acid compound obtained with a polyethylene oxide product and alkali, M2O, the latter in a molar amount SiO2/M2O
greater than 4.

11. The process according to Claim 9 or Claim 10, wherein the polycondensation/precipitation is performed at a pH below 5, and where the molar ratio is between 6 and 100.

12. The process according to Claim 9, in which soluble alkali silicates such as metasilicate, waterglass or other alkali salts of acids weaker than silicic acid such as boric acid is used for the alkalization step.

13. The process according to any of Claims 9, 10 or 11, in which the silicic acid product is prepared by polycondensation/
precipitation of a soluble acidic (oligomer) silicic acid in the presence of a soluble aluminium salt at a pH below 3 by increasing the pH to between 4-9 and also increasing the temperature in the range of 60-100°C.

14. The process according to Claim 9, including pre-paring a dispersed or colloidal silicic acid stabilized with alkali by removing all alkali from an alkali silicate solution by ion exchange and addition of a small amount of stabilizing alkali, removing/neutralizing part of the alkali of an alkali silicate solution by addition of an acid in the presence of a polyethylene oxide compound to the extent that the stabilizing alkali (active to silicic acid) corresponds to a molar ratio SiO2/M2O of at least 4.

15. The process according to Claim 9, including pre-paring a dispersed or colloidal silicic acid stabilized with alkali by removing/neutralizing part of the alkali of an alkali silicate solution by addition of an acid in the presence of a polyethylene oxide compound to the extent that the stabilizing alkali (active to silicic acid) corresponds to a molar ratio SiO2/M2O of at least 4.

16. The process according to Claim 14 or Claim 15, wherein the molar ratio is between 5 and 100.