NL2029851B1

NL2029851B1 - Dry powder paint composition and method for producing a dry powder paint

Info

Publication number: NL2029851B1
Application number: NL2029851A
Authority: NL
Inventors: Willem Frederik Van Der Schaaf Jacques; Antoinette Petronella Geelen Patricia; Maria Catharina Hendriks Margo
Original assignee: Earthyhome Holding B V
Priority date: 2021-11-21
Filing date: 2021-11-21
Publication date: 2023-06-13

Abstract

The invention relates to a dry powder paint composition, comprising at least one mineral based filler, at least one pigment, at least one binder, , at least one 5 dispersing additive, preferably at least one lecithin based dispersing additive, wherein the dry powder paint composition further comprises additives configured to create an effervescent effect when the dry powder paint composition comes into contact with water.

Description

Dry powder paint composition and method for producing a dry powder paint

The invention relates to a dry powder paint composition. The invention also relates to a method of producing a compacted dry powder paint composition.

Conventional paints are typically oil-based or water-based. Water-based paints got more and more popular over time due to being more friendly to the environment because of their lower volatile organic compounds (VOC) level when compared to oil-based paints. Water-based paints further benefit of quicker drying and repainting times. However, a drawback of water-based paints is they require the use of biocides in order to prevent microbial issues within the paint and to increase the shelf life. Biocides have a relative high toxicity and paint containing biocides have the potential to cause skin sensitisation or allergic contact dermatitis. Biocides may further be a cause for irritation of the respiratory system. Hence, there is a desire to omit the use of biocides, in particular when stored under dry conditions. It is for example possible to omit the use of biocides in a water-based paint by using a dry powder paint which is only mixed with water at the time of use. Since such paint can be prepared at the moment of use, there is no concern of microbial growth.

However, there are quite some challenges when it comes to developing a dry powder paint which can compete with conventional water-based paints. A dry powder paint composition should also not be confused with a dry powder based tinting material. The use of powder based tinting materials is known in the art, where said tinting materials are applied as colourant for conventional paints.

However, a tinting material is a subproduct and not a final paint product. A tinting is material is not a paint neither can it be used as such. A paint requires the presence of a filler which gives body to the actual paint layer which is to be applied as well as different functionalities such as hardness and scratch resistance, and a binder required for sufficient film-forming. The provision of a dry powder paint composition which needs to be mixed with water in order to prepare a decent (liquid) paint is associated with several challenges. There need to be an optimal mix between the filler(s), the binder(s) and further additive(s). Further, in order to provide an environmentally friendly product, it is desired to limit the use of (toxic) chemical components. Therefore the use of biobased and/ or biodegradable ingredients is preferred.

Hence, it is a first goal of the invention to provide a dry powder paint which is at least partially bio-based and which is not hazardous for the human health and the environment.

A further goal of the invention is to produce a dry powder paint wherein the use of water during the production process is omitted.

The invention provides thereto a dry powder paint composition, comprising: — at least one filler, preferably a mineral based filler; — preferably at least one pigment; — at least one binder, said binder preferably comprising at least polysaccharide and/or at least one biobased binder; — preferably at least one dispersing additive, preferably at least one lecithin based dispersing additive; wherein the dry powder paint composition further comprises: o at least a fraction of sodium bicarbonate and a fraction of citric acid in particular configured to create an effervescent effect when the dry powder paint composition comes into contact with water; and o at least one defoamer and/or at least one disintegrant, and preferably wherein the dry powder paint composition is provided in a compacted form.

The dry powder paint composition, and in particular the compacted dry powder paint composition, is configured to be mixed with water such that a liquid paint composition is obtained. The compacted dry powder paint composition according to the present invention has several benefits over the prior art. Due to the provision of the dry powder paint composition in a compacted form, the risk of handling harmful dust particles is avoided. Further, the product according to the present invention enables easy dosing for the preparation of the final liquid paint. In fact, both the amount of dry powder which is needed prepare the required amount of liquid paint as well as the amount of the liquid paint itself can be easily controlled thereby preventing unnecessary leftovers. The residual (chemical) waste of conventional liquid paints is typically enormous as it is difficult to use limited amounts and due to leftover paint only having a limited lifetime. This drawback is overcome by the dry powder paint composition according to the present invention.

A further benefit of the dry powder paint composition according to the present invention is that it is easily miscible with and/or at least partially dissolvable in water. The presence of at least a fraction of sodium bicarbonate and a fraction of citric acid which are configured to create an effervescent effect when the dry powder paint comes into contact with water enables that the dry powder composition dissolves easily in water or a water based solution, without the use of more vigourous (mechanical) steering. Enabling that the dry powder paint composition is sufficiently mixed and/or dissolved in water is needed as for the dry powder paint the spreading and the degree of solubility of the dry composition within the water is essential for the provision of a decent liquid paint. Since a dry powder paint composition requires a relatively high amount of filler, which is needed to form a film/paint layer, makes that this is a challenge. It is beneficial that the sodium bicarbonate and citric acid are included in the powder composition, and in particular within the compacted form thereof, as this will facilitate that they will be activated from the core of the composition. This is preferred over separate addition of additives to facilitate mixing and/or an effervescent effect. The presence of sodium bicarbonate and citric acid might further even results in that the need for mechanical mixing or mechanical steering can be fully omitted. In fact, the fractions of sodium bicarbonate and citric acid provide that if a compacted dry powder paint composition is provided, the product can act as an effervescent tablet which is easy to dissolve in water.

A drawback of the (desired) effervescent effect of the sodium bicarbonate and citric acid is that there will be foam formation when the dry powder paint composition is dissolved. The presence of foam can negatively affect the consistency of the (liquid) paint and also the ability to equally spread the paint upon a target surface. It was found that the presence of at least one defoamer and/or the presence of at least one disintegrant within the dry powder paint composition can tackle this drawback. The defoamer can deactivate or counteract the formed foam, as no foam in the final product is desired because this will reduce the final appearance of the paint upon application. The at least one disintegrant, if applied, may provide a similar effect. The dry powder paint composition according to the present invention comprises an optimal combination of both components which provide an effervescent effect as well as at least one components which reduces and/or prevents the negative and/or undesired side-effects thereof.

Itis beneficial if the composition comprises a mineral based filler, a binder, preferably a biobased binder optionally comprising at least polysaccharide, and at least one lecithin based dispersing additive as these are natural ingredients. This results in the product itself and the residue thereof being benign.

The dry powder paint composition according to the present invention further benefits of an extremely long shelf life, in particular when stored under dry conditions. The dry powder paint composition according to the present invention is basically mixable with a liquid and/or at least partially soluble in liquid, in particular water. It can also be said that the dry powder paint composition is configured for use in a liquid or a liquid solution. The dry powder paint composition is in particular configured for use in combination with water. The invention is suitable for use in any type of water, for example but not limited to tap water, demineralize-, deionized-, and/or distilled water or even rainwater or groundwater. When it is referred to water, also a water based or aqueous solution can be meant.

The dry powder paint composition as such is free of volatile organic components (VOCs). When the dry powder paint composition is dissolved in water, there will also be no VOCs released. This can be at least partially explained by the fact that the use of conventional (synthetic) binders, solvents and/or plasticizers as used in convention liquids paints can be omitted. Said components which are applied in water-based paints are typically a cause of the release of VOCs. The use of a dry powder composition according to the present invention enables that the liquid paint which is obtainable therewith is substantially VOC free but also scent and/or odour free. This also results in that there is no waiting period for a room to be used which is recently painted with a dry powder paint composition according to the present invention. This means that the dry powder paint composition is highly suitable for use in for example in the domestic environment and even in medical environments, such as hospitals. This feature also enables that the paint is highly suitable for, for example, short term renovation or rearrangement projects which need to be delivered immediately.

The dry powder paint composition is preferably provided in a compacted form. The dry powder paint composition in a compacted form can for example be a tablet, pellet, cube and/or capsule. The compacted form of the dry powder paint 5 composition can be referred to as a dry powder paint product. The compacted dry powder paint composition benefits of the fact that there is no severe risk of dust particles when handling the material. A drawback of the use of a dry powder paint is that the dust particles thereof may cause difficulties in production, transport and use. The dusty condition of a dry powder paint can be hazardous for the human health during handling and possible inhalation of small particles. Hence, it is desired to provide the dry powder paint in more compact form to have a more safe product to handle. The compacted dry powder paint composition according to the present invention is preferably obtained via a compacting and/or compressing process. Hence, it is conceivable that heat and/or pressure is applied in order to compact a fraction of the dry powder paint composition. In a preferred production method, a compacted dry powder paint composition is obtained via a compacting and/or compressing process preferably under ambient conditions. Depending on the nature of the composition, applying heat might negatively affect the final product. A straightforward solution to prevent that a dusty product is provided would be to pelletize the dry powder paint composition. However, the common production method of producing pellets requires a lot of water and evaporation thereof which is undesired from environmental and economical point of view.

In a preferred embodiment, sodium bicarbonate and citric acid are present in a ratio of at least 1:1, preferably at least 1.5:1, and more preferably at least 2:1. lt was experimentally found that such ratio provides a good effervescent effect when the dry powder paint composition comes into contact with water. Hence, a sufficient production of gas, thereby causing a mixing effect wherein clogging of particles is prevented is achieved when a ratio, of at least 1:1, preferably of at least 1.5:1, and more preferably at least 2:1 is applied. It is further preferred that the dry powder paint composition comprises at least 4 wt% sodium bicarbonate and citric acid, preferably at least 6 wi%, most preferably at least 8 wt®%. The dry powder paint composition preferably comprises at most 12 wt% sodium bicarbonate and citric acid, preferably at most 10 wt%, most preferably at most 9 wt%. It is preferred to control the effervescent effect by limiting the amount of sodium bicarbonate and/or citric acid in order to prevent an excess of foam formation when the dry powder paint composition is dissolved in water. In a non-limitative preferred embodiment, the dry powder paint composition comprises in the range of 2-6 wt% sodium bicarbonate and/or in the range of 1-3 wt% citric acid.

As indicated above, the filler is an important component of a dry powder paint. The filler provides the basis for the eventual paint layer which is to be formed. The dry powder paint composition preferably comprises at least 40 wt% filler, more preferably at least 50 wt% filler, even more preferably at least 60 wt%, or even at least 70 wt®%. It is conceivable that the dry powder paint composition comprises up to 75 wt% filler or even up to 80 wt®% or 85 wt%. The dry powder paint composition can comprise multiple types of fillers. At least one filler is preferably a mineral based filler. It is also conceivable that the dry powder paint composition comprises at least one mineral based filler. A mineral based filler can have a positive effect on the properties of the resulting paint layer or film layer, for example when it comes to strength and/or coverage. The use of a mineral filler may also positively contribute to the application behaviour of the (fluid) paint. At least one mineral based filler can comprise for example talc and/or calcium carbonate. It is for example conceivable that at least one filler comprises precipitated calcium carbonate. Precipitated calcium carbonate benefits of a bright white colour and of a uniform narrow particle size distribution making it a consistent and practical base element. It is also conceivable that at least one filler comprises aluminum oxide (Al203) and/or calcium oxide (CaO). However, it is also conceivable that at least one filler comprises calcium carbonate, magnesium carbonate, dolomite, gypsum, hydrous candite clay, anhydrous candite clay, talc, mica, pearlite, feldspar, kasumi stone flash rock, wollastonite, diatomaceous earth, barite, glass, natural silica and/or combinations thereof. It is also conceivable that kaolin, bentonite and/or barium sulphate are used in particular as a pigment extender.

The at least one dispersing additive is preferably configured to at least partially prevent flocculating of particles of the dry powder paint composition when dispersed in a liquid. The dispersing additive(s) can further positively contribute to a smooth and/or homogeneous distribution of the particles of the dry powder paint composition when dispersed in liquid media. The dispersing additive may also be configured to stabilize at least one pigment and/or filler. The dry powder paint composition preferably comprises at least one lecithin based dispersing additive. At least one dispersing additive can for example comprise soy lecithin and/or rapeseed lecithin. Said additives benefit of being natural additives. The dry powder paint composition typically comprises a relatively small fraction of one lecithin based dispersing additive. It is for example conceivable that the dry powder paint composition comprises at most 2 wt% dispersing additive, preferably at most 1 wt®%, more preferably at most 0.5 wt%. It is for example conceivable that the dry powder paint composition comprises in the range of 0.05 to 1 wt% lecithin based dispersing additive, in particular in the range of 0.1 to 0.75 wt%.

It is preferred that the dry powder paint composition comprises at least one natural binder, It is for example possible that at least one binder comprises at least polysaccharide. It is also conceivable that at least one binder comprises acacia gum, arabica gum, heteropolysaccharide, galactose, casein, caproyl glycerin/sebacic acid copolymer, gelatin, starch, alginic acid, rosin and/or borax. It is also imaginable that at least one binder comprises acacia senegal gum or gum extract. However, alternatively or additionally, it is also conceivable that the dry powder paint composition comprises at least one binder comprising vinyl acetate, ethylene and/or vinyl ester, butyl acrylate monomer, ethyl acrylate monomer and/or latex. It is also imaginable that a combination of natural and synthetic binders is applied. The abovementioned binders may additionally have a positive effect on the stability of the paint. It is possible that the dry powder paint composition comprises at least 10 wt®% binder, preferably at least 12.5 wt®% and more preferably at least 15 wi%. It is for example conceivable that the dry powder paint composition comprises inthe range of 10-25 wt% binder.

At least one pigment, if applied, is preferably a natural pigment. At least one pigment, and in particular at least one natural pigment, preferably comprises ochres, oxides, dioxide umbres and/or vegetable dyes. It is conceivable that at least one pigment is an organic pigment. However, it is also conceivable that the dry powder paint composition comprises at least one organic pigment. The colour of the applied pigment can be determined based upon the indented application of the paint. At least one pigment can also be a white pigment. Typically, only a relatively small fraction of pigment is required within the dry powder paint composition to provide a sufficient colouring effect. This is beneficial as the commonly known pigments are typically insoluble in water or solvents. It is for example imaginable that the dry powder paint composition comprises at most 5 wit% pigment, preferably at most 2.5 wt%, more preferably at most 1 wt%.

Itis commonly known to apply titanium dioxide (TiO2) as a white pigment in paint.

Titanium dioxide typically scatters visible light, thereby imparting whiteness, brightness and opacity when incorporated into a paint or coating. It is conceivable that in an alternative embodiment, the dry powder paint composition according to the present invention comprises a fraction of titanium dioxide. However, since titanium dioxide is a suspected carcinogen by inhalation under European

Regulation, it is preferred to omit the use of titanium dioxide. The invention also includes an embodiment of a dry powder paint composition which is substantially free of titanium dioxide. It is for example conceivable that the dry powder paint composition according to the present invention comprises a white pigment on the basis of a synthetic zinc sulfide, zinc oxide, manganese dioxide, lime carbonate, lithopone, magnesium carbonate, permanent white, barium titanate, barium ferrite, barium sulphate, calcium carbonate and any other known by a person skilled in the art. Hence, the dry powder paint composition may comprise at least a fraction of zinc sulfide.

At least part of the particles forming the dry powder paint composition are preferably substantially homogenous in shape and/or size. This is good for the stability of the product but also for enabling a homogeneous distribution of the paint and will prevent demixing of the powder upon storage in particular before preparing a compressed form. At least part of the particles of the dry powder paint composition preferably have an average particle size in the range of 2 to 100 um, for example in the range of 30 to 100 um. lt is for example conceivable that at least part of the particles of the dry powder paint composition preferably have an average particle size in the range of 60 to 90 um or in the 65 to 85 range um.

However, it is also conceivable that at least part of the particles of the dry powder paint composition preferably have an average particle size in the range of 10 to 50 um or in the 15 to 30 range um. An average particle size of the particles of the dry powder paint composition can for example be in the range of 40 to 80 um.

The dry powder paint composition according to the present invention is preferably substantially free of biocides. It is also conceivable that the dry powder paint composition is substantially dairy free. The dry powder paint according to the present invention may be vegan.

It is conceivable that at least one disintegrant, if applied, comprises at least one swelling agent. It is for example conceivable that the disintegrant and/or the swelling agent provides a capillary function. This can actively counteract the foam formation and/or the foam already formed.

At least one defoamer can for example comprise hydrophobic solids and foam- destroying fat derivatives. At least one defoamer may for example comprise of polyglycols, vegetable oil, paraffin oil, hydrophobic esters, polyalkylene glycol, silicone oil, polyethers, higher alcohols and/or mineral oil. In a possible embodiment, the dry powder paint composition comprises at least 0.2 wt% defoamer , preferably at least 0.5 wt%, more preferably at least 1 wt% and most preferably at least 1.5 wt®%. lt is intended to determine an optimal ratio of the components which provide an effervescent effect and the component(s) which reduces and/or prevents the negative and/or undesired side-effects of said effervescent effect. lt is also imaginable that the dry powder paint composition comprises at least 0.2 wt% disintegrant, preferably at least 0.5 wt%, more preferably at least 1 wt% and most preferably at least 1.5 wt%.The dry powder paint composition could for example comprises at most 2.5 wi% defoamer and/or at most 2.5 wt% disintegrant, preferably at most 1.5 wt%, more preferably at most 1 wt% and most preferably at most 0.5 wt%. At least one defoamer is preferably organic and/or silicone-free. At least one defoamer can for example comprise at least one oil, in particular rapeseed oil. it is also conceivable that the dry powder paint composition comprises at least one emulsifier and/or at least one reactive surfactant. The emulsifier and/or surfactant may comprise an anionic polyoxyethylene alkyl ether sulfate, fatty acid, fatty alcohol sulfone ester, alkyl sulfone ester and/or nonionic sorbitan esters. The dry powder paint composition may also comprise any further additives, such as but not limited to at least one thickening agent and or at least one stabilizer. At least one thickening agent could for example comprise bentonite, kaolin, activated phyllosilicate, cellulose fiber, xantagon, non-ionic cellulose ether and/or carboxymethyl cellulose.

Alternatively, the invention also relates to a dry powder paint composition, comprising at least one mineral based filler, at least one pigment, at least one binder, said binder preferably comprising at least polysaccharide, at least one dispersing additive, preferably at least one lecithin based dispersing additive and wherein the dry powder paint composition further comprises at least one disintegrant. The dry powder paint composition is preferably provided in a compacted form. Said disintegrant may comprises at least one swelling agent. It is for example conceivable that the disintegrant and/or the swelling agent provides a swelling effect which cause the (compacted) dry powder paint composition to decompose in liquid. The disintegrant is therefore typically configured to enable that the dry powder paint composition is sufficiently mixed and/or dissolved in water is needed as for the dry powder paint the spreading and the degree of solubility of the dry composition within the water is essential for the provision of a decent liquid paint. This alternative embodiment can be combined with any of the above described embodiments of the invention.

The invention also relates to a dry powder paint composition, comprising at least one filler, preferably at least one pigment, at least one binder and at least one dispersing additive, wherein the dry powder paint composition further comprises sodium bicarbonate and citric acid and preferably at least one defoamer and/or at least one disintegrant. The dry powder paint composition may be provided in a compacted form. The invention also relates to a tablet comprising a dry powder paint composition according to the present invention. Said composition can be any of the described embodiment. When it is referred to a dry powder paint composition also a dry powder paint, powder paint or powder paint composition can be meant.

The invention further relates to a method for producing a dry powder paint or a dry powder paint product, in particular a compacted dry powder paint composition, comprising the provision of a dry powder paint composition according to the present invention and compressing and/or compacting at least a fraction of the dry powder paint composition into a compacted form. Hence, the invention relates to a method for producing a dry powder paint or a dry powder paint product, comprising the steps of providing a dry powder paint composition according to the present invention and compressing and/or compacting at least a fraction of said dry powder paint composition into a compacted form. The compacted form of the dry powder paint composition can be referred to as a dry powder paint product. The method may include the steps of applying heat and/or pressure in order to compact a fraction of the dry powder paint composition. In a preferred production method, a compacted dry powder paint composition is obtained via a compacting and/or compressing process under ambient conditions. A benefit of said method is that the use of process water and corresponding additional energy for an evaporation step can be omitted. The dry powder paint composition can be compacted by solely subjection said composition to a (predetermined) pressure.

The invention will be further elucidated based upon the following non-limitative clauses. 1. Dry powder paint composition, comprising: — at least one mineral based filler; — at least one pigment; — at least one binder, said binder preferably comprising at least polysaccharide; — at least one dispersing additive, preferably at least one lecithin based dispersing additive; wherein the dry powder paint composition further comprises: o optionally at least a fraction of sodium bicarbonate and a fraction of citric acid configured to create an effervescent effect when the dry powder paint composition comes into contact with water; and/or o at least one defoamer and/or at least one disintegrant, and wherein the dry powder paint composition is provided in a compacted form. 2. Dry powder paint composition according to clause 1, wherein sodium bicarbonate and citric acid are present in a ratio of at least 1:1.

3. Dry powder paint composition according to any of the previous clauses, comprising at least 4 wt% sodium bicarbonate and citric acid, preferably at least 6 wt%, more preferably at least 8 wt%.

4 Dry powder paint composition according to any of the previous clauses, comprising at least 50 wt®% filler, preferably at least 60 wt%, more preferably at least 70 wt%.

5. Dry powder paint composition according to any of the previous clauses,

wherein at least one mineral based filler comprises talc and/or calcium carbonate. 6. Dry powder paint composition according to any of the previous clauses, comprising at least one filler comprising aluminum oxide and/or calcium oxide.

7. Dry powder paint composition according to any of the previous clauses, wherein at least one dispersing additive comprises soy and/or rapeseed lecithin. 8. Dry powder paint composition according to any of the previous clauses, comprising at most 2 wt% dispersing additive, preferably at most 1 wt%, more preferably at most 0.5 wt%.

9. Dry powder paint composition according to any of the previous clauses, wherein at least one binder comprises acacia gum, arabica gum, heteropolysaccharide, galactose, casein, caproy! glycerin/sebacic acid copolymer,

gelatin, starch, alginic acid, rosin and/or borax.

10. Dry powder paint composition according to any of the previous clauses, wherein at least one binder comprises vinyl acetate, ethylene and/or vinyl ester.

11. Dry powder paint composition according to any of the previous clauses, comprising at least 10 wt% binder, preferably at least 12.5 wt%, more preferably at least 15 wi%.

12. Dry powder paint composition according to any of the previous clauses,

comprising at most 5 wt% pigment, preferably at most 1 wi®%.

13. Dry powder paint composition according to any of the previous clauses, wherein at least part of the powder has an average particle size in the range of 30 to 100 pm. 14. Dry powder paint composition according to any of the previous clauses, wherein the composition is free of titanium dioxide. 15. Dry powder paint composition according to any of the previous clauses, wherein the disintegrant comprises at least one swelling agent. 16, Dry powder paint composition according to any of the previous clauses, comprising at least 0.5 wt% defoamer, preferably at least 1 wt%, more preferably at least 1.5 wt%. 17. Dry powder paint composition according to any of the previous clauses, comprising at least one emulsifier and/or at least one reactive surfactant. 18. Method of producing a compacted dry powder paint composition, comprising the provision of a dry powder paint composition according to any of clauses 1-17 and compressing and/or compacting at least a fraction of the dry powder paint composition into a compacted form. it will be clear that the invention is not limited to the exemplary embodiments which described here, but that countless variants are possible within the framework of the attached claims, which will be obvious to the person skilled in the art. In this case, it is conceivable for different inventive concepts and/or technical measures of the above-described variant embodiments to be completely or partly combined without departing from the inventive idea described in the attached claims.

The verb ‘comprise’ and its conjugations as used in this patent document are understood to mean not only ‘comprise’, but to also include the expressions ‘contain’, ‘substantially contain’, formed by’ and conjugations thereof.

Claims

Conclusions

A dry powder vericomposition comprising: — at least one mineral-based filler; — at least one pigment; - at least one binding agent, said binding agent preferably comprising at least one polysaccharide; — at least one dispersant, preferably at least one lecithin-based dispersant; wherein the dry powder paint composition further comprises: o at least a fraction of sodium bicarbonate and a fraction of citric acid adapted to create an effervescent effect when the dry powder paint composition comes into contact with water; and o at least one defoamer and/or at least one disintegrant, and wherein the dry powder paint composition is provided in a compacted form.

A dry powder paint composition according to claim 1, wherein sodium bicarbonate and citric acid are present in a ratio of at least 1:1.

3. Dry powder paint composition according to any of the preceding claims, comprising at least 4% by weight of sodium bicarbonate and citric acid, preferably at least 6% by weight, more preferably at least 8% by weight.

4. Dry powder paint composition according to any of the preceding claims, comprising at least 50% by weight of filler, preferably at least 60% by weight, more preferably at least 70% by weight.

A dry powder paint composition according to any one of the preceding claims, wherein at least one mineral-based filler comprises talc and/or calcium carbonate.

Dry powder paint composition according to any of the preceding claims, comprising at least one filler comprising aluminum oxide and/or calcium oxide.

A dry powder paint composition according to any one of the preceding claims, wherein at least one dispersant comprises soya and/or rapeseed lecithin.

8. Dry powder paint composition according to any of the preceding claims, comprising at most 2% by weight of dispersant, preferably at most 1% by weight, more preferably at most 0.5% by weight.

A dry powder paint composition according to any one of the preceding claims, wherein at least one binder comprises gum acacia, gum arabic, heteropolysaccharide, galactose, casein, caproylglycerin/sebacic acid copolymer, gelatin, starch, alginic acid, rosin and/or borax.

A dry powder paint composition according to any one of the preceding claims, wherein at least one binder comprises vinyl acetate, ethylene and/or vinyl ester.

11. Dry powder paint composition according to any of the preceding claims, comprising at least 10% by weight of binder, preferably at least 12.5% by weight, more preferably at least 15% by weight.

12. Dry powder paint composition according to any of the preceding claims, comprising at most 5% by weight of pigment, preferably at most 1% by weight.

A dry powder paint composition according to any one of the preceding claims, wherein at least part of the powder has an average particle size in the range of 30 to 100 µm.

A dry powder paint composition according to any one of the preceding claims, wherein the composition is free of titanium dioxide.

A dry powder paint composition according to any one of the preceding claims, wherein the disintegrant comprises at least one swelling agent.

16. Dry powder paint composition according to any of the preceding claims, comprising at least 0.5% by weight of defoamer, preferably at least 1% by weight, more preferably at least 1.5% by weight.

A dry powder paint composition according to any one of the preceding claims, comprising at least one emulsifier and/or at least one reactive surfactant.

A method of making a compacted dry powder paint composition comprising providing a dry powder paint composition according to any one of claims 1-17 and compressing and/or densifying at least a fraction of the dry powder paint composition into a compacted form.