WO1998017765A1

WO1998017765A1 - A composition, a process for treating a non-porous surface and a non-porous surface so treated

Info

Publication number: WO1998017765A1
Application number: PCT/EP1997/005931
Authority: WO
Inventors: John Somerville Armstrong
Original assignee: Agency Design Services Limited
Priority date: 1996-10-23
Filing date: 1997-10-23
Publication date: 1998-04-30
Also published as: AU5314098A; GB9622095D0

Abstract

The invention concerns a composition for treating a non-porous surface to render it repellent to liquids. The composition comprises a silicone polymer and a curing agent in a suitable solvent. The non-porous surface may be a vitreous, ceramic, metal or plastics surface.

Description

A COMPOSITION, A PROCESS FOR TREATING A NON-POROUS SURFACE AND A NON-POROUS SURFACE SO TREATED

This invention relates to a composition; a process for treating a non-porous, for example, vitreous, ceramic, metal or plastics surface; and a non-porous surface so treated. The non-porous surfaces so treated are repellent to liquids, or to deposits or residues from liquids.

Untreated non-porous surfaces are inclined to, for example, soil, stain, corrode, or lose lustre due to the wetting action of the liquids thereon.

It is an object of the present invention to obviate or mitigate this disadvantage.

It will be understood that the term "treating" as used herein can embrace, but does not necessarily embrace, the cleaning of the non-porous surface.

According to a first aspect of the present invention, there is provided a composition for treating a non-porous surface, the composition comprising a silicone polymer, a curing agent, optionally, a sequestering agent and, optionally, a surfactant in a suitable solvent.

According to a second aspect of the present invention there is provided a process for treating a non-porous surface, the process comprising treating the non-porous surface with the composition according to a first aspect of the present invention. According to a third aspect of the present invention there is provided a non- porous surface whenever treated by a process according to a second aspect of the present invention.

The application of this composition provides, on curing, a durable coating film bonded to the so treated non-porous surface, the coating film having high gloss and low smear properties. The coating film confers water repellancy and inhibits re-staining. It will be appreciated that any curing agent, which, upon application to the non-porous surface, cures the silicone polymer to form a coating film on the non-porous surface, is contemplated in the present invention.

Preferably, the silicone polymer is a dimethylsiloxane, more preferably, a long chain dimethylsiloxane. Polysiloxanes are commercially available in a wide range of molecular weights and viscosities. The viscosity of the polysiloxane is desirably 200/350 centistokes.

In a preferred embodiment, the silicone polymer is used in the form of an aqueous dispersion or emulsion. The emulsifying agent is preferably non-toxic. One preferred emulsifying agent is alkylphenoxy polyethylene ethanol. Typical suitable, commercially available emulsions are Dow Corning 36, 346 and 347. Other suitable commercially available emulsions include, but are not limited to, Silicone Glycols from Basildon Chemicals, such as BC 330/60, BC 91/096, BC 330 LV, BC 85/124 and BC 403, of which BC 403 is preferred.

One particularly preferred silicone polymer is Dow Corning (RTM) 193 Surfactant, which is a silicone glycol co-polymer. The silicone polymer may be incorporated into the composition at concentrations ranging from 0.01 % to 80% by weight, preferably 0.01-20% by weight.

The curing agent may be a N-acyl sarcosine of the general formula:-

R - C - N - CH, - COOH

CH,

wherein R is an alkyl radical derived from any commercially available fatty acid. The salt may be formed by any conventional manner. Preferably, a sodium salt is used. Due to the greater acidity of N-acyl sarcosines, the sodium salts are less alkaline than the corresponding fatty acid soaps. A preferred salt is N- lauroyl sarcosinate. It is believed that the sarcosinate interacts with the silicone polymer as both a solubilising and curing agent. In addition, since it is strongly absorbed onto surfaces, it improves the silicone film forming process. It has good wetting, foaming and anti-static characteristics and results in a highly pleasing finish. It is generally used at a 1 % concentration, and a level of 2.5% should not be exceeded or excessive foaming could be experienced. A range of N-acyl sarcosines and sodium sarcosinates are commercially available under the Trade Mark Crodasinic.

Alternatively, the curing agent may be a hydroxy acid or its salt, preferably citric acid or its salt. The citric acid or its salt may be used at up to 20% concentration, preferably 1.0-10% concentration , and further preferably 2-8% concentration. If the composition is to be used at elevated temperatures such as, for example, 50°C-100°C as would pertain to its use as a dishwasher rinse aid, a N-acyl sarcosinate or a salt thereof is preferred as curing agent. If the composition is to be used at ambient temperatures such as, for example, 0°C-35°C as would pertain to its use as a windscreen washer fluid, a hydroxy acid or its salt is preferred as curing agent.

The sequestering agent, if present, may be any one of a group of hydroxy acids or salts, preferably citric acid. Alternatively, the sequestering agent may be a dicarboxylic acid or a salt thereof such as adipic acid, succinic acid or glutaric acid; or a salt thereof; or a mixture thereof. Further alternatively, the sequestering agent may be ethylenediamine tetraacetic acid (EDTA) or a salt thereof. The sequestering agent is highly effective at combating stubborn stains, particularly those which are of hard water type in origin. In the composition of the present invention, the sequestering agent may be present at a concentration of up to 20%, preferably 2-15% by weight. It will be appreciated that the group of hydroxy acids or salts can act as both curing agents and as sequestering agents.

The surfactant, if present, is advantageous for wetting surfaces, low foaming and giving a fast drain which improves the final streak-free shine. The surfactant may be non-ionic. Preferably, the surfactant is a poly-glycol ether of a synthesis alcohol having a medium chain length of C₁₃ with a general formula:

R - CH₂ - 0(CH₂CH₂0)_n H

wherein R is an alkyl radical and n=number of ethylene oxide molecules added and is preferably between 5 and 15. The surfactant may be used at a concentration of up to 10%, preferably 2-7 5% by weight One such suitable surfactant is Genapol 2908

In a preferred embodiment, the composition of the invention may also contain certain nonionic surfactants to remove lipstick residue from glassware or the like

Such nonionic surfactants include the following groups, all of which are included within the scope of the present invention -

(1 ) Ethoxylates of primary or secondary fatty alcohols of various chain length, which are adducts of ethylene oxide with fatty alcohols, the fatty alcohol end groups being uncapped.

(2) Alkoxylates of primary or secondary fatty alcohols of vaπous chain lengths which are adducts of ethylene oxide, propylene oxide or higher alkylene oxides and fatty alcohols

(3) Ethoxylates or alkoxylates of fatty alcohols of various chain lengths with capped end groups, in which the free hydroxide groups of the nonionic surfactant are esteπfied with an alkyl group

(4) Propylene oxide/ethylene oxide or ethylene oxide/propylene oxide block co- polymers

(5) Ethoxylates or alkoxylates of alkyl phenols

(6) Amine ethoxylates or alkoxylates (7) Alkyl polyglucosides

(8) Fatty amine oxides

(9) Fatty acid alkanolimides.

(10) Fatty acid alkyl glucamides.

(11 ) Methoxylates, ethoxylates or alkoxylates of mono- or di- carboxylates (esters of mono- or di- carboxylic acids) Mixtures of any or all of the above- mentioned nonionic surfactants are also contemplated in the present invention Specifically, such mixtures include, but are not limited to, mixtures of various members of the Synperonic CF/RA series such as binary mixtures of LF/RA 310 and 30 and of 30 and 260 and of 310 and 260 and ternary mixtures of LF/RA 290, 30 and 310 and of LF/RA 30, 3 0 and 260; mixtures of various members of the Plurafac LF series such as binary mixtures of 400 and 401 , and ternary mixtures of a binary mixture of members of the Synperonic LF/RA series with another nonionic surfactant such as binary mixtures of Synperonic LF/RA 310 and 30 with a member of the Ethylan CPG series and binary mixtures of Synperonic LF/RA 310 and 30 with a member of the Synperonic A series

Ideally, the nonionic surfactants should conform to the requirements of EU directive 82/242 concerning a minimum primary biodegradability of 80% within 21 days under specified test conditions.

It is preferred that the compositions of the present invention, if used in a dishwasher, should include a low foam nonionic surfactant. The term "low foam" can be defined by measuring the rotation rate of a spray arm in a dishwasher. Thus, a low foam Plurafac LF surfactant would allow more than 80 rev/min at 60°C, when 5 parts of the surfactant and 95 parts of the builder were tested at a concentration of 20g/l in the presence of 10ml of egg to encourage foaming.

Alternatively, any conventional foam suppressant may be added to the composition of the present invention.

Water is a preferred suitable solvent for the composition of the present invention. Alternatively, any solvent compatible with the constituents of the composition may be used. It is envisaged that a short-chain alcohol, preferably isopropanol, would be also suitable as a solvent.

It is preferred that a co-solvent be present, with water as the solvent, in the composition of the present invention. It is believed that the co-solvent acts as a hydrotope so as to help retain the composition in a single phase. Whilst any short chain alcohol is suitable for this purpose, isopropyl alcohol is preferred. Glycols and sodium cumene sulphonate are also suitable as co-solvents.

It is preferred that the nonionic surfactant is an alkoxylated alcohol. Examples of commercially available suitable nonionic surfactants include, but are not limited to, the following:-

(1 ) The Plurafac LF series from BASF pic of Cheshire, England. This series of nonionic surfactants, which are low foaming, are alkoxylated, predominantly unbranched fatty alcohols which contain higher alkene oxides as well as ethylene oxide. The fatty alcohols may be short, medium or long chain fatty alcohols. Preferred from this series are LF 120, 223, 224, 400, 401 , 403, 404, 131 , 231 , 132, 700, 1300 and 1430 and most preferred are LF 400, 401 , 403 and 404. In this connection, Plurafac LF 403 is a C12-18 largely linear, ethoxylated, propoxylated aliphatic alcohol.

(2) Plurafac PE series from BASF pic. These are low foaming nonionic surfactants which are made from propylene oxide-ethylene oxide block co- polymers.

(3) Ethylan CPG series from Accrues Chemicals of Manchester, United Kingdom. These are nonionic surfactants which are modified alcohol ethoxylates. Preferred are CPG 630, CPG 7545, CPG 816 and CPG 945, of which CPG 945 is the most preferred.

(4) The Synperonic LF/RA series from ICI Surfactants of Cleveland, United Kingdom. These are nonionic surfactants and comprise alkoxylated alcohols. From this series, LF/RA 30, 260, 310 and 290 are most preferred. It is believed that Synperonic LF/RA 290 is a low foam wetter having a good balance on the conflicting requirements of wetting and foam control andlhat Synperonic LF/RA 30 and 310 are foam controlled detergents exhibiting excellent wetting performance at more elevated temperatures.

(5) The Synperonic A series from ICI Surfactants of Cleveland, United Kingdom. These are ethoxylated alcohols, based on "Synprol", a C13/C15 detergent alcohol. From this series, A5, having a hydrophilic/lipophilic balance (HLB) of 10.2, is preferred.

(6) The Volpo T series from Croda Chemicals Limited. These are ethoxylated derivatives of tridecanol. (7) The Lutensol T series from BASF pic and the Synperonic 13 series from ICI Surfactants. These are alkyl polyglycol ethers of tridecanol, a fatty alcohol.

(8) The Estasol series from Chemoxy International pic of Cleveland, United Kingdom. Estasol is a mixture of three dimethyl dicarboxylate esters.

Specifically, Estasol comprises 15-25% dimethyl succinate, 55-65% dimethyl glutarate and 12-23% dimethyl adipate. Estasol is less desired as a nonionic surfactant, since its presence in the glasswashing composition can be detected by the presence of an "ester" odour. The Estasol series also includes Estasol MD10 which comprises greater than 95% methyl decanoate, a methyl ester of mono-carboxylic acid.

It is desirable that the nonionic surfactant have a HLB in the range 8-12, preferably 9-11. It is also desirable that the nonionic surfactant have the wetting properties of a surfactant used as rinse aid Suitable nonionic surfactants for use in the glasswashing compositions of the present invention should, therefore, be selected to enable water to run off quickly and evenly after the final rinse.

The composition of the present invention may also include a cross-linking agent. Preferably, the cross-linking agent is an amino-functional-based- silicone. It is believed that such agents not only share the film-forming ability of the siloxane polymers but also, due to the polar nature of the amino-functional group, have the ability to cure and form cross-linking bonds. A suitable cross- linking agent would be Dow Corning 2-8707, which is a cationic emulsion of amino functional polydimethyl silanol fluid. If a silicone based cross-linking agent is used, adjustment of the overall silicone content of the composition may be required. Silicone based cross-linking agents may be used in concentration of up to 30% by weight, preferably 0.5-10% by weight, in the compositions of the present invention. Preferably, such silicone based cross-linking agents are used in a 1 :0.1-7.5, preferably 1 :0.2-5.7 ratio (silicone based cross-linking agent : silicone polymer).

The composition of the present invention may further include a thickener, such as Carbopol (RTM; Carboxypolymethylene) or Kelzan (RTM; Xanthan gum). Alternatively Dowanol DPM (RTM; Dipropyleneglycolmethylether) may be used as a thickener.

The composition of the present invention may be formed from first and second components, the first component comprising a silicone polymer; a curing agent such as N-acyl sarcosine or citric acid or a salt thereof; and a solvent, preferably a lower (C_1-6) aliphatic alcohol or, alternatively, water and the second optional component comprising a sequestering agent and a surfactant, preferably a non-ionic surfactant in a solvent, preferably a lower (C_1-6) aliphatic alcohol or, alternatively, water.

The silicone polymer, sarcosine, sequestering agent and surfactant are as hereinbefore defined.

The solvent must be compatible with the remaining constituents of the first component. If the solvent is an alcohol, it should, preferably, be volatile at room temperature so as to evaporate readily from the treated non-porous surface and, thereby, aid in the drying of the composition on the non-porous surface. Such suitable lower aliphatic alcohols may be monohydric (straight or branched) alkanols, such as methanol, ethanol, propanol, isopropanol, butanol or isobutanol. The alcohol acts as a solvent for the other two constituents of the first component. In the first component, the silicone polymer is preferably used in a concentration of 1-21 % but about 2% and about 14% are preferred. If the curing agent is sarcosine, it is preferably present at about 2% of the first component and if the curing agent is citric acid, it is preferably present at about 4% of the first component

In the second component, the sequestering agent, if present, is preferably used in a concentration of between about 3% to 30%, more preferably about 25% The sequestering agent may be any one of a group of hydroxy acids or salts, preferably citric acid or a salt thereof

The surfactant is preferably used in a concentration of between about 1 % and 40%, more preferably 15-30% of the second component

The first and second components may be stored separately and, in that event, are combined in equal proportions, usually immediately prior to use

It will be appreciated that the term coating" as used herein includes the "lining" of a suitable non-porous surface e g the inner lining of tubing or a pipe

The application of the composition of the present invention may be by any means which allows a coating film to be formed on a non-porous surface One such means is as a rinse aid in domestic and industrial dish-washing machines The protective effect produced has been observed to improve with repeated applications i e the effect is cumulative with repeated applications and results in a modification to the surface of the article The treatment not only improves appearance and resists re-staining, but also, in the case of treated vessels or containers, helps to reduce de-aeration in carbonated beverages This latter effect is particularly noticeable with commercial alcoholic beverages such as beers, ales or stouts, thereby aiding beer head retention and imparting improved "lacing" of the head residue on the treated surface If certain nonionic surfactants are included, the composition of the invention may also be used to remove lipstick residue from glassware and the like.

Another envisaged application of the composition of the present invention is as a vehicle windscreen washer fluid. Tests have shown that glass surfaces so treated show improved visibility and are more repellent to adherence of insects and the like. In addition, due to improved water repellence and improved repellence to deposits and residues, windscreen wiper usage is reduced so that windscreen wipers last longer.

A still further envisaged application of the composition of the present invention is as a toilet block. In that event, the toilet block releases, upon flushing, an amount of composition containing a bacteriostatic or bacteriocidal agent, so that the non-porous surface of the toilet bowl is coated with a protective coating containing the bacteriostatic or bacteriocidal agent.

A further envisaged application of the composition of the" present invention is as a cleaning composition. In particular, it is envisaged that the composition can be used as: a glass cleaning composition, for example a window cleaning composition; a ceramic cleaning composition for use on, for example, hobs, cookers and enamelled surfaces; a cleaning composition for soft surfaces such as plastics; and a cleaning composition for painted surfaces such as vehicles and vehicle body parts.

Embodiments of the present invention will now be described by way of examples. Example 1

For the coating process of the present invention, the following formulations of a coating composition may be used:

A B

Dow Corning (RTM) 346 20% 10%

Crodasinic (RTM) LS 30 1 % 0.5%

Citric Acid 15% 5%

Genapol (RTM) 2908 2% 2%

Water 62% 82.5%

These coating compositions are suitable for use as a dishwasher rinse aid provided that the rinse fluid temperature is less than 65 °C since Dow Corning 346 begins to break up at 65 °C. These coating compositions are also suitable for use as a windscreen washer fluid for stationary vehicles - the coating compositions may be cloudy for a few seconds after application to the windscreen.

When it is desired to include a cross-linking agent in the above formulation, 3% of Dow Corning 2-8707 can replace 3% of the Dow Corning 346.

Example 2

The following formulations are also possible as coating compositions:

A B Dow Corning 193 Surfactant or

Dow Corning 346, 347 or 36 emulsion 20% 10%

Crodasinic LS 1 1 % 0.5%

Citric Acid 15% 5% Genapol 2908 5% 1% Dow Corning 2-8707 2% 0.2% Water 57% 83.3%

These coating compositions, if Dow Corning 193 is included, are suitable for use as a dishwasher rinse aid at rinse fluid temperatures of up to about 90° C or more.

Example 3 The following two component formulation may be used:

1st Component ' 2nd Component

Dow Corning (RTM) 200/350 Citric Acid 23% as silicone fluid 14% Genapol 2908 15% Crodasinic (RTM) LS 30 2% Water 62% Isopropanol 84%

A coating composition is formed as a 1 :1 mixture (v/v) of these first and second components.

Example 4

The following formulations may be used:

Formulation: A B

Citric Acid 15% 7.5%

Dow Corning 346 17% 8.5%

Genapol 2908 2% 1%

Dow Corning 2-8707 3% 0.5%

Crodasinic LS 30 1 % 0.5%

Water 62% 82% The compositions are suitable for use as a dishwasher rinse aid.

Example 5

Dow Corning (RTM) 193 2%

Citric Acid 4%

Isopropanol 10%

Genapol 2908 1%

Water 83%

This coating composition rapidly provides a protective coating on non-porous surfaces such as, -for example, vehicle windscreens. Tests have shown that this coating composition has a shelf life of at least one year. The coating film has been found to last for up to a month under normal driving conditions, when coated onto a vehicle windscreen.

Example 6

The following coating composition:

Citric Acid 2.5%

Silicone 193 2.5%

Isopropanol 10%

Synperonic LF/RA 30 5.0%

Synperonic LF/RA 310 2.5%

Synperonic LF/RA 290 7.5%

Water balance

is formed from a 1 :1 mixture (v/v) of the following first and second components: First Component

Citric Acid 5%

Silicone 193 5%

Genapol 2908 2%

Isopropanol 10%

Water balance

Second Component

Synperonic LF/RA 30 10%

Synperonic LF/RA 310 5%

Synperonic LF/RA 290 15%

Isopropanol 10%

Water balance

The above composition is suitable for coating non-porous surfaces such as windscreens The above composition is also suitable for use as a dishwasher rinse aid and was found to effectively remove lipstick residue without affecting beer head retention.

Example 7

Citric Acid 2%

Q2-5211 Superwetting Agent 0.01%

Isopropanol 10%

Synperonic LF/RA 30 5%

Synperonic LF/RA 310 2.5%

Synperonic LF/RA 290 7.5%

Water balance Q2-5211 Superwetting agent, which is supplied by Dow Corning, comprises a low viscosity, nonionic poly-oxyethylene-modified polydimethyl-siloxane, more commonly referred to as a silicone glycol copolymer.

The above composition effectively coated non-porous surfaces such as windscreens. The above composition is also suitable to use either as a dishwasher detergent or as a dishwasher rinse aid.

Example 8

The following formulation of a composition may be used for cleaning non- porous surfaces: -

Dow Corning (RTM) 193 2%

Dow Corning (RTM) Q2-5211 0.5%

Citric Acid 4%

Isopropanol 10%

Water 83.5%

This cleaning composition is suitable for use as a vehicle window or windscreen cleaning composition.

Example 9

The following formulation is also possible as a cleaning composition:

Dow Corning (RTM) 193 2%

Dow Corning (RTM) 2-8707 0.5%

Citric Acid 4%

Isopropanol 10%

Water 83.5% Dow Corning (RTM)2-8707 which is a cationic emulsion of functional polydimethylsilanol-fluid, is a preferred cross-linking agent. The composition of

Example 9 is also suitable for use as a vehicle window or windscreen cleaning composition.

Example 10

The following formulation is also possible as a cleaning composition:

Dow Corning (RTM) 193 4%

Crodasinic (RTM) LS 30 2%

Citric Acid 8%

Isopropanol 15%

Water 71%

This cleaning composition is also suitable for use as a vehicle window or windscreen cleaning composition.

Example 11

The following formulation is also possible as a cleaning composition.

Dow Corning (RTM) 193 1%

Citric Acid 2%

Crodasinic (RTM) LS 30 0.5%

Isopropanol 10%

Water 86.5%

This composition is suitable for use as a general window cleaning composition. Example 12

The following formulation is also possible as a cleaning composition.

Dow Corning (RTM) 193 1 % Dow Corning (RTM) 2-8707 0.5%

Citric Acid 2%

Isopropanol 10%

Water 86.5%

This composition is suitable for use as a general window cleaning composition.

Example 13

The following formulation is also suitable as a cleaning composition:

Dow Corning (RTM) 346 8%

Citric Acid 3%

Crodasinic (RTM) LS 30 1 %

Dow Corning (RTM) 2-8707 2%

Thickener 10% Water 76%

The thickener comprises 2% Carbopol in water. The composition of Example 13 is suitable for use as a cleaning composition for ceramic surfaces.

Example 14

The following formulation is also suitable as a cleaning composition:

Dow Corning (RTM) 347 6%

Dow Corning (RTM) Q2-5211 0.5% Dow Corning (RTM) 2-8707 3%

Citric Acid 4%

Isopropanol 10%

Water 76.5%

This composition is suitable for use as a cleaning composition for plastic surfaces.

Example 15 The following formulation is also suitable as a cleaning composition:

Dow Corning (RTM) 2-8707 10%

Dow Corning (RTM) 193 2%

Crodasinic (RTM) LS 30 1 % Citric Acid 5%

Dowanol D.P.M. 10%

Water 72%

This composition is suitable for use as a cleaning composition for painted surfaces such as vehicles and/or vehicle body parts.

Claims

1. A composition for treating a non-porous surface, the composition comprising a silicone polymer and a curing agent in a suitable solvent.

2. A composition according to Claim 1 , in which the solvent is water at a concentration of 25-95% by weight, preferably 30-87.5% by weight.

3. A composition according to Claim 1 or 2, in which a co-solvent is present at a concentration of 5-50% by weight, preferably 10-45% by weight.

4. A composition according to Claim 3, in which the co-solvent is a short chain alcohol, preferably isopropanol.

5. A composition according to any one of Claims 1-4, in which the silicone polymer is a silicone glycol copolymer.

6. A composition according to Claim 5, in which the Silicone polymer is a polydimethylsiloxane.

7. A composition according to any one of Claims 1-6, in which 0.01-80% by weight, preferably 0.01-20% by weight, of the silicone polymer is present.

8. A composition according to any one of Claims 1-7, in which the curing agent is a N-acyl sarcosine of the general formula:- 0

II

R - C - N - CH₂ - COOH

CH, in which R is a alkyl radical derived from a fatty acid, or a salt thereof.

9. A composition according to Claim 8, in which the curing agent is N- lauroyl sarcosinate.

10. A composition according to Claim 8 or 9, in which the curing agent is present at 0.1-2.5% by weight, preferably 0.5-2% by weight, most preferably about 1 % by weight.

11. A composition according to any one of Claims 1-7, in which the curing agent is a hydroxy acid or a salt thereof.

12. A composition according to Claim 11 , in which the curing agent is citric acid or a salt thereof.

13. A composition according to Claim 11 or 12, in which the curing agent is present at 1-20% by weight, preferably 1-10% by weight,^' most preferably 2-8% by weight.

14. A composition according to any one of Claims 1-13, in which a sequestering agent is present.

15. A composition according to Claim 14, in which the sequestering agent is a hydroxy acid or a salt thereof.

16. A composition according to Claim 15, in which the sequestering agent is citric acid or a salt thereof.

17. A composition according to Claim 15 or 16, in which the sequestering agent is present at 1-20% by weight, preferably 2-15% by weight.

18. A composition according to any one of Claims 1-17, in which a surfactant is present, preferably a nonionic surfactant, or a mixture thereof.

19. A composition according to Claim 18, in which the nonionic surfactant is a polyglycol ether of an alcohol of the formula:-

R-CH₂-O(CH₂CH₂O)_nH

in which R is an alkyl radical and n is preferably between 5 and 15.

20. A composition according to Claim 18 or 19, in which the nonionic surfactant is present at 0.1-10% by weight, preferably 2-7.5% by weight.

21. A composition according to Claim 18, in which the^" nonionic surfactant is selected from the group comprising alkoxylates, preferably ethoxylates, of primary or secondary fatty alcohols; ethylene oxide/propylene oxide block co- polymers; and short-chain alkyl esters of mono- or di- carboxylic acids.

22. A composition according to Claim 21 in which the nonionic surfactant is a low foam surfactant.

23. A composition according to Claim 21 or 22, in which the nonionic surfactant is an alkoxylate of a primary or secondary fatty alcohol, in which the end groups are capped.

24. A composition according to any one of Claims 21-23, in which the nonionic surfactant is present in the range 0.1-50%(w/w), preferably 2- 45%(w/w), most preferably about 15% (w/w).

25. A process for treating a non-porous surface, the process comprising treating the non-porous surface with a composition as claimed in any one of the preceding claims.

26. A non-porous surface whenever treated by a process as claimed in Claim 25.