GB2412377A - Coating formulation comprising methacrylic ester-acrlyic ester copolymer binder - Google Patents

Abstract

A coating formulation for coating substrates such as walls comprises, in admixture: [i] a film-forming methacrylic ester-acrylic ester copolymer binder which is dispersible in water and which hardens on drying; [ii] a water-soluble thickener, such as methylhydroxyethyl cellulose; [iii] a filler, including a calcium carbonate based filler and [iv] quartz sand. The formulation may further comprise an anionic emulsifier, a defoaming agent, a pH fixing agent and a surface sanitising agent containing a bacteriocide and/or a fungicide.

Description

Title: Improved Formulation The present invention relates to an improved

formulation for use m the coating of surfaces such as walls, and to an improved method for coating such surfaces.

In the known method used by tradesmen such as housebuilders to provide a coating for walls, a sheet material such as plasterboard is attached in a multistage process, onto a substrate such as blockworktoprovideafinishedwallsystem. The plasterboard initiallyneeds to tee fixed to the substrate, then generally two coats of plaster are applied followed by a wall coating, such as paint.

This multistage process has the disadvantage that it is extremely time consuming and expensive, and ] O requires reliance upon anumberofdifferent skilled trades, which skills are in increasinglyshort supply.

It Is an object ofthe present invention to provide a formulation which is suitable for use in coating substrates such as walls in which the above disadvantages are reduced or substantially obviated.

] 5 It is a further object ofthe present invention to provide an improved method for use in coating substrates such as walls in which the above disadvantages are reduced or substantially obviated.

The present invention provides a formulation for use in coating substrates such as walls, which formulation comprises, in admixture; (i) a firm-forming methacrylic ester- acrylic estercopolymerbinderwhich is dispersible in water and which hardens on drying; (h) a water-soluble thickener and (ii i) a filler and (iv) a quartz sand. :

Suitable binders include the methacrylic ester - acrylic ester copolymers sold under the trade mark Plextol byPolymer Latex GmbH of Marl, Germany, in particular Plextol D540 and Plextol XA 425.

In a further preferred embodiment ofthe formulation according to the invention, the water-soluble thickener is preferably a water- soluble cellulose, in particular a methylhydroxyethyl cellulose with a high degree of etherification. Suitable celluloses include the methylhydroxyethyl celluloses sold under the trade mark Walocel MT by Wolff cellulosics of Walsrode in Germany.

The filler is preferably a calcium carbonate based filler, for example the filler sold under the trademark Durcal by Omya AG, in particular Durcal 40.

I () The quartz sand is for example a pyrites free rounded quartz sand in which each grain is enveloped in a synthetic resin film dyed with an inorganic or organic pigment to the required colour. The quartz sand is commerciallyavailable in a range of different particle sizes, between 0. 4to 0.8 mm and 3.0 to 5 mm. The particle size may be selected according to the finish required.

The formulation may further comprise a non-aqueous solvent, such as an ether acetate solvent, for example butyl glycol acetate or butyl diglycol acetate.

The formulation may further comprise an anionic emulsifier, such as the anionic emulsifierwhich is present in commercially available acrylic binders such as Plextol.

The formulation may further comprise a surface sanitising agent, in particular a surface sanitising agent which contains an active bacteriocide and/or and active fungicide. Suitable sanitising agents include the surface sanitising agents sold under the trade markParmetol, in particular Parmetol DF 12, by Schulke & Mayr GmbH of Norderstedt in Germany.

The formul ation may further compri se a defoaming agent, in particular a mineral oi l or si Scone based powderydefoaming agent. Suitable dcSoaming agents include the defoaming agents sold under the l, trade mark Agitan, in particular Agitan 281, by Munzing Chemie of Helbronn m Germany.

The formulation may further comprise apH fixing agent such as concentrated ammonato stabilise the acrylic binder.

A preferred embodiment of the coating formulation according to the invention comprises from 20 to 25% by weight of a binder component comprising; (I) from 80 to 95%, more preferably from 85 to 95%, by weight of the film- forming methacrylic ester - acrylic ester copolymeric binder, based on the dry weight of the formulation, ; (ii) from 0.2 to 1.5%, more preferably from 0.5 to 1%, by weight of the water-soluble I thickener, based on the dry weight of the formulation; (iii) from 2 to 10%, more preferably from 3 to 8%, by weight of a filler, based on the dry 3 weight of the formulation; (iv) from O to 10%, more preferably from 3 to 8% by weight of the non- aqueous solvent, based on the dry weight of the formulation; 1 5 (v) from 0 to 1%, more preferably from 0.2 to 0.6% byweight ofthe surface sanitising agent, based on the dry weight of the formulation and, (vi) from O to 1%, more preferably from 0.2 to 0.6%byweight ofthe defoamingagent, based on the dry weight of the formulation, formed into a mortar with water and r 2() from 75 to 80% by weight of quartz sand.

The formulation according to the invention is mixed with water, either in situ where it is to be 3 applied to the wall or similar surface, or remotely. Where a large quantity of material is required, ; the mixing may be carried out in a mixer such as a concrete mixer. Where only a small quantity of material is required, for example for repair or infilling work, the mixing may be manual.

The formulation according to the invention is particularly suitable for use as an alternative to; traditional gypsum plaster, over which it has the following advantages: lN Novel formulation Gypsum plaster Only one application is required. At least two applications, base and top coat, are required.

2 - 3mm coverage. 10 - 15mm coverage.

There is no need for a perfect finish The plaster must be professionally finished.

to the base surface.

The coating is waterproof without Non waterproof: treatment.

Suitable for interior and exterior Suitable for interior applications only.

] 0 applications.

The coating is non-skip and may The surface is not non-slp.

therefore be used where a non-slip surface is required.

The coating can be cleaned leaving There is a high probability of staining.

no watermarks either for maintenance within residence or at construction stage prior to handover.

2() The coating is pre-coloured, so that Requires paint/paper/tiling.

there is no need to paint.

Infinite colour options are available. )

The curing period is 48-72 hours at median site temperatures.

The shrinkage rate is low. Relatively high shrinkage rate.

Due to advantageous elastomeric Unable to accommodate movement/shrnkagc in properties, the system Is able to the underlying surface/structure without cracking.

accommodate movement/shrnkage in the underlying surface/structure without cracking.

Improved soundproofing and thermal Relatively poor soundproofing and thermal qualities. qualities.

The invention will now be described with reference to the following Example:

Example

A formulation comprising 5.0 parts by weight of Walocel MT 30 OOOPV (solid); 29 parts by weight of butyl diglyco] acetate; 3.0 parts by weight of Parmetol DF 12; 644.0 parts by weight of Plextol D 540; I.3 parts by weight of Agitan 281; 20.() parts by weight of Durcal 40 1.7 parts by weight of concentrated ammonia (25% industrial compound) and 296 parts by weight of water was prepared as described below and was mixed with 400() parts by weight of quartz sand according to the following method: 5.() parts byweight of Walocel MT 30 OOOPV was mixed with 150 parts by weight of wafer with agitation. The mixture was agitated strongly for 10 minutes and then allowed to stand without further \ J agitation for 24 hours. A clear paste without lumps was produced.

The mixture was added to a further 146.0 parts by weight of water with further agitation, followed l:'y29 parts byweight of butyl diglycol acetate again with agitation.3.0 parts by weight of Parrnetol DF 12 were added with agitation and the mixture was agitated for 10 minutes.

644.0 parts by weight of Plextol D 540 were added with agitation followed by 1.3 parts by weight of Agitan 281 with agitation.20.0 parts by weighs of Durcal 40 were added with agitation followed by I.7 parts byweight of concentrated ammonia with agitation. The mixture was agitated for 10 minutes and then allowed to stand without further agitation lor 24 hours.

The sand was mixed with the binder in the specified proportions, by placing the binder in an 1 () appropriate container provided with an agitating paddle and adding until it could no longer be mixed, i.e. it was too thick to be agitated by the "paddle". The mixed materials were poured onto a board and applied to a wall that had been "primed" with a diluted solution of Plextol 540 or any other "unibond" type solution.

The materials were applied and finished with standard plasterers' tools, i.e. trowels of varying shapes and sizes, and worked to a finish. This working Is subject to the surface to which the material is being applied.

The material was applied at a coverage of approximately 3mm, Welch corresponded to a coverage of 2.5 times the actual particle size. This is the minimum coverage which is required to create the critical mass required. The material covered very quickly and the finishing requirements/skill levels required were much reduced from those required when applying traditional gypsum plaster In addition, no specific detailing was required for joining to the previous day's work.

in the event of damage and/or problems during drying resulting i n, for example, a poor or rough Gnash, the surface can be reheated and reworked and so patch repaired.

At temperatures of at or below 10 degrees Centigrade the surface is cured/ready after 72 hours. \ J

Claims (12)

1. Claims I. A formulation for use in coating substrates such as walls, which

   formulation comprises, in admixture; (i) a film-forming methacrylic ester - acrylic ester copolymer binder which Is dispersible in water and which hardens on drying; (ii) a water-soluble thickener; (iii) a filler and ('v) a quartz sand.
2. 2. A formulation according to claim I wherein the water-soluble thickener is a water- soluble l O cellulose.
3. 3. A formulation according to claim 2 wherein the water-soluble thickener isa methylhydroxyethyl cellulose with a high degree of ctherification.
4. 4. A formulation according to any of claims 1 to 3 wherein the filler includes a calcium carbonate based filler.

   l
5. 5 5. A formulation according to any of claims I to 4 wherein the quartz sand is a pyrites free rounded quartz sand in which each grain is enveloped m a synthetic resin Elm dyed with an inorganic or organic pigment
6. 6. A formulation accordingtoanyofclaims l to 5 whichfurthercomprises anon- aqueous solvent.
7. 7. A formulation according to claim 6 in which the non-aqueous solvent is an ether acetate solvent.
8. 8. A formulation according to claim 7 in which the non-aqueous solvent is butyl glycol acetate or butyl diglycol acetate.
9. ). A formulation according to any of claims I to 8 which further comprises an anionic emulsifier.
10. 10. A formulation according to anyofclaims l to 9 which t;rthercomprises a surface sanitising agent.
11. I I. A formulation according to claim 10 in which the surface sanitising agent contains an active bacteriocide and/or and active fungicide.
12. 12. A formulation according to anyofclaims I to I l which I; uthercomprises adefoammg agent.

    1 3. A fonnulabon according to claim 12 in which the deforming agent is a mineral oil or silicone based powdery det'oaming agent.

    ] 4. A formulation according to any of claims I to 13 which further comprises a pH fLxing agent.

    1 5. A formulation according to any of claims] to 14 which comprises from 20 to 25 /, by weight of a binder component comprising; (I) from 80 to 95% by weight of the film-fonnulg methacrylic ester - acrylic ester copolymer binder, based on the dry weight of the formulation; (ii) from 0.2 to 1.5% by weight of the water-soluble thickener, based on the dry 1() weight ofthe formulation; (ifi) from 2 to] 0 /0 by weight of a calcium carbonate-based filler, based on the dry weight of the formulation; (iv) I'rom O to 1 0 /O by weight ofthe non-aqueous solvent, based on the dryweight of the formulation; 1 5 (v) from 0 to 1% byweigTht ofthe surface sanitising agent, based on the dry weight of the formulation and (v') from O to 1% by weighs ofthe deforming agent, based on the dryweight ofthe formulation fonned into a mortar with water and from 75 to 80% by weight of the quartz sand filler.

    I G. A formulation substantially as herein described and with reference to the accompanying

    Example.