WO2008117242A2

WO2008117242A2 - Decorative paint coating with optically interactive properties

Info

Publication number: WO2008117242A2
Application number: PCT/IB2008/051112
Authority: WO
Inventors: Enrico Fiorito
Original assignee: O. Brignola S.P.A.
Priority date: 2007-03-26
Filing date: 2008-03-25
Publication date: 2008-10-02
Also published as: WO2008117242A3; ITMI20070605A1

Abstract

The invention relates to a painting system comprising a painting product (1) containing from 30 to 50% w/w of microcrystalline calcium carbonate and a painting product (2) containing from 0.70 to 4.0% w/w of a pigmenting organic compound (I) chosen from among the salts and/or terephthalic acid esters, and from 96.0 to 99.3% w/w of a mixture (II) containing from 1.0 to 5.0% w/w of hydrated potassium, sodium and aluminium silicate, and from 0.20 to 0.40% w/w of an aluminium-potassium silicate and titanium dioxide compound. Said painting system produces an attractive decorative effect.

Description

Title

DECORATIVE PAINT COATING WITH OPTICALLY INTERACTIVE PROPERTIES

Description

[0001] The present invention relates to an optically interactive painted decorative coating. More in particular, the present invention refers to a water-based painting system, to the procedure for producing the painting system, and to the method for applying said decorative coating.

[0002] The coating of the present invention serves as a decorative element by virtue of its optical and tactile properties.

[0003] In particular, the coating of the present invention gives a particular aesthetic effect to the painted surface, due to the creation of lighting effects such as chiaroscuro and depth, in combination with monochromatic variations and a variety of colours that can become dichroic and change in brilliance. These effects are created depending on the angle of observation or the type of light source, and according to laws of optical physics, such as light interference, reflection and diffusion.

[0004] From the tactile standpoint, the coating of the present invention transmits a pleasant, "warm" feeling and an embossed effect.

[0005] The coating of the present invention also offers the advantage of being very easy to wash.

[0006] The final appearance of the painted surface is consequently suitable for use as a decorative element in the preparation of rooms of prestige, especially when they are lit by oblique or incident light sources.

[0007] The above-mentioned effects and results are achieved by means of a painting system that comprises an extender with a given particle size distribution, interactive pigmenting compounds (which may be organic and inorganic), and a hollow spheroid filler with a given particle size distribution.

[0008] Thus, the object of the present invention is a water-based painting system comprising the following aqueous products: (1) a painting product (1 ) comprising (parts by weight): from 30 to 50% w/w of microcrystalline calcium carbonate with a particle size distribution from 5 μm to 60 μm, water q.s. to 100% w/w; (2) a painting product (2) comprising (parts by weight): from 0.70 to 4.0% w/w of a pigmenting organic compound (I) chosen from among the salts and/or terephthalic acid esters and from 96.0 to 99.30% w/w of a mixture (II) comprising (w/w): from 1.0 to 5.0% w/w of hydrated potassium, sodium and aluminium silicate, with a particle size distribution from 5 μm to

150 μm; from 0.20 to 0.40% w/w of a compound of aluminium-potassium silicate and titanium dioxide with a particle size distribution from

50 to 1000 μm, water q.s. to 100% w/w.

[0009] As a filler, the painting product (1) comprises microcrystalline calcium carbonate in the form of granules. The particle size distribution of these granules typically varies from 5 μm to 60 μm, and preferably from 10 μm to 40 μm. From 65 to 85% of these granules are typically, but not in a limiting way, have a particle size distribution of approximately 10 μm and from 15 to 35% of them have a particle size distribution of approximately 40 μm.

[00010] The painting product (2) comprises a pigmenting organic compound (I) preferably chosen from among the salts and/or terephthalic acid esters; polyethylene glycol terephthalate is preferably chosen, which is a polyester obtained from methyl terephthalate and ethylene glycol. In the case of salts, these are generally aluminium salts. Said compound is in the form of flakes. The size of the flakes is roughly as follows: between 150 and 240 μm, and preferably between 180 and 200 μm, in length; and between 15 and 30 μm, and preferably between 20 and 25 μm in thickness. Said compound is preferably added in a quantity coming between 0.70 and 4.0, and preferably between 1.0 and 3.50% w/w of the total weight of the product (2). The pigmenting organic compound (I) is an interactive pigment.

[00011] In addition to the above-mentioned pigmenting organic compound (I), the product (2) also comprises a mixture (II) consisting of hydrated potassium, sodium and aluminium silicate combined with compounds consisting of aluminium-potassium silicate and titanium dioxide.

[00012] An example of said hydrated potassium, sodium and aluminium silicate is expanded riolite. Such a silicate comes in the form of granules, with a particle size distribution roughly ranging from 5 μm to 150 μm, and preferably from 10 μm to 110 μm. From 40 to 60% of such granules typically, but not in a limiting way, have a particle size distribution from 30 μm to 70 μm. Said silicate acts as multicellular hollow spheroid filler. This hydrated potassium, sodium and aluminium silicate is in quantities ranging from 1.0 to 5.0% w/w of the weight of the mixture (II).

[00013] As mentioned previously, the mixture (II) also comprises a compound consisting of aluminium-potassium silicate and titanium dioxide (compound [II]); such a compound contains a quantity of titanium dioxide coming approximately between 5 and 15% w/w of the whole compound (II). Said compound (II) is preferably in the form of flakes with dimensions typically ranging from 50 to 1000 μm, and preferably from 70 μm to 700 μm. The compound (II) is in quantities ranging from 0.2 to 0.4% w/w of the mixture (1). Said compound (II) is an interactive pigment.

[00014] In addition to the above-mentioned components, the products (1 ) and (2) also contain other components belonging to functional classes that are usually found in painting products and are consequently well known to a person skilled in the painting field. One or more compounds of the same functional class may be contained (i) in the same product (1) or (2).

[00015] Some examples of compounds usually included in the composition of painting products, and preferably contained in both the products (1) and (2), are structuring additives, antifoam agents, preserving agents, pH stabilising agents, deairing agents, binders, rheological additives and fluidizing agents.

[00016] For the structuring additive, for instance, the choice is between hydroxyethyl cellulose, acrylic polymers in an aqueous dispersion or anionic aqueous emulsion, polymethacrylic acid in a low-viscosity aqueous dispersion, and polyurethane solutions in a water-based mixture. The preferred additives are hydroxyethyl cellulose and acrylic polymer in an anionic aqueous emulsion. When this agent is contained in the product (1), it is roughly in a quantity varying from 0.150 to 0.50% w/w. When contained in the mixture (II), it is roughly in a quantity ranging from 0.60 to 5.0% w/w.

[00017] The choice of antifoam agents includes, for instance, paraffin mineral oils in combination with polysiloxane polyethers, polyalkoxyesters or emulsions of amorphous silicon polymers, polysiloxane, etc. When said agent is contained in the product (1 ), it is roughly in a quantity that varies from 0.050 to 0.30% w/w. When contained in the mixture (II), said agent is roughly in a quantity that varies from 0.050 to 0.50% w/w.

[00018] A preserving agent with a bactericidal function may be chosen preferably from among the derivatives of isothiazolinone, such as chloromethylisothiazolinone and chromomethyl-methylisothiazolinone- bromopol and mixtures thereof. When said agent is contained in the product (1 ), it is roughly in a quantity that varies from 0.10 to 0.450% w/w. When contained in the mixture (II), said agent is roughly in a quantity that varies from 0.050 to 0.30% w/w.

[00019] A pH stabiliser enables the required alkaline pH to be maintained. Suitable stabilising agents include, for instance, amine derivatives such as aminomethyl propanol and triethanolamine, and sodium hydroxide in an aqueous solution. When said agent is contained in the product (1 ), it is roughly in a quantity that varies from 0.10 to 1.0% w/w. When contained in the mixture (II), said agent is roughly in a quantity that varies from 0.050 to 0.40% w/w.

[00020] Such deairing agents include, for instance, paraffin waxes in alkylated hydrocarbons and polysiloxanes. When these agents are contained in the product (1), they are roughly in a quantity that varies from 0.010 to 0.20% w/w. When contained in the mixture (II), these agents are roughly in a quantity that varies from 0.10 to 1.0% w/w.

[00021] The binders used in water-based paints include, for instance, acrylic acid and its derivatives, such as methacrylic acid and the polymers of said acids, in suspension or emulsion; in the case of these polymers being copolymers, the comonomers may be acrylic acid, methacrylic acid, or styrene. For example, the binders may be included both as a mixture of acrylic and methacrylic monomers in an aqueous emulsion, and as acrylic polymers in emulsion. When these agents are contained in the product (1 ), they are roughly on a quantity that varies from 15.0 to 30.0% w/w. When contained in the mixture (II), these agents are roughly on a quantity that varies from 17.0 to 70.0% w/w. When in the mixture (II), they preferably include both acrylic and methacrylic monomers in an aqueous emulsion and acrylic polymers in emulsion, the former typically amounting to 7.0 to 30.0% w/w and the latter typically to 10.0 to 40% w/w.

[00022] The rheological additives include, for instance, silicon compounds, e.g. silicates, such as sodium, lithium and magnesium silicate, and hydrated silicon dioxide. These additives serve the purpose of increasing the viscosity of the paint when it is applied with a brush, or alternatively of reducing its viscosity when the paint is applied with a spatula. When these agents are contained in the product (1), they are roughly in a quantity that ranges from 1.0 to 1.5% w/w. When contained in the mixture (II), these agents are roughly in a quantity that varies from 1.0 to 2.0% w/w.

[00023] Fluidizing agents serve the purpose of "smoothing" the film, avoiding an excessively "orange peel" appearance. An example is monoethylene 1 ,2- dihydroxypropane. When such agents are contained in the product (1 ), they are roughly in a quantity that varies from 0.5 to 2.0% w/w. When contained in the mixture (II), such agents are roughly in a quantity that varies from 2.0 to 8.0% w/w.

[00024] In addition to the above-mentioned compounds, the product (1) also includes other compounds, which may be contained in paints, such as dispersing agents and ion sequestering agents.

[00025] The dispersing agents are chosen, for instance, from among the ammonium salts of a carboxylic acid, possibly in the form of a polymer like the polyacrylates, acrylic linear polymers, aminomethyl propanol, sodium salts of polycarboxylic acids, and mixtures thereof. Their purpose is to prevent lumps from forming and, at the same time, they make it easier to apply the painting system because they have the effect of fluidifying the mixture. When contained in the product (1), these agents are roughly in a quantity that varies from 0.10 to 0.60% w/w.

[00026] The ion sequestering agents include, for instance, the salts of polyphosphoric acids, and sodium polyphosphates in particular; a specific example is sodium hexametaphosphate (also known as Graham's salt). When contained in the product (1), such agents are roughly in a quantity that varies from 0.20 to 2.0% w/w.

[00027] In addition to the above-mentioned compounds, the mixture (II) also includes other compounds that may be contained in painting products, such as fillers and film formation agents.

[00028] Examples of fillers include aluminium and magnesium silicate, in the form of flakes, for example. When they are contained in the mixture (II), these agents are roughly in a quantity that varies from 3.0 to 10.0% w/w.

[00029] The film formation agents, for instance, are isobutyric acid ester derivatives, such as 2,2,4-trimethyl-1 ,3-pentadiol-monoisobutyrate. When these agents are contained in the mixture (II), they are roughly in a quantity that varies from 0.20 to 1.50% w/w.

[0003O] In addition to the previously-mentioned components, the painting system may also comprise further pigmenting substances, such as pearlescent pigments and "metallic" glitters that add further aesthetic effects to the decorative coating of the present invention.

[00031] Another object of the present invention consists in the process for producing the previously-described painting system. Said system is prepared by separately producing the painting products (1 ) and (2), as explained below. After their preparation, the painting products (1) and (2) applied separately, one after the other, to the surface being painted.

[00032] The products (1) and (2) are prepared simply by mixing in the mixers commonly used in the painting field; the mixing can be done under the following conditions (unless clearly specified otherwise): at room temperature and at a speed of approximately 100-250 revolutions per minute (rpm), and preferably 150-200 rpm, using an impeller 400 mm long. The following is a description of the components of each product and, for each of these, a specification of the preferred quantities in terms of their proportions by weight (w/w) of the product (1), the mixture (II) and the product (2).

[00033] The product (1) is obtained, for instance, using a process that consists of two phases. The first phase involves the preparation of three separate mixtures, i.e. mixture (i), mixture (ii) and mixture (iii), as described in detail below. In the second phase, such mixtures are mixed together to obtain a mixture (I). Such second phase of the process consists, in turn, of two subsequent stages: in the first stage the mixture (ii) is mixed with the mixture (i), while in the second stage the mixture (iii) is added to the mixture obtained in the first stage.

[00034] The mixtures (i)-(iii) are obtained simply by mixing the components together in the specified w/w proportions of the product (1).

[00035] The first mixture, mixture (i), is prepared by mixing the following components: water, from 5 to 31 % w/w; structuring agent, from 0.15 to 0.5% w/w; ion sequestering agent, from 0.20 to 2.0% w/w; dispersing agent, from 0.10 to 0.60% w/w; preserving agent, from 0.050 to 0.20% w/w; and antifoam agent, from 0.050 to 0.30% w/w.

[00036] Calcium carbonate (from 30.0 to 50.0% w/w) is added to the resulting mixture, which is mixed at high speed, typically 500-600 rpm, with a 400 mm long impeller, at a temperature of approximately 45-55°C and for approximately 10-20 minutes after it has been added. At the end of said interval, the following are added in the following order: pH stabiliser, from 0.10 to 1.0% w/w; and water, from 0.30 to 0.50% w/w.

[00037] The mixture (ii) is obtained by mixing: a binder in an aqueous emulsion, from 15.0 to 30.0% w/w; and water, from 20.0 to 40.0% w/w. The mixture (iii) is obtained simply by blending together: fluidizing agent, from 0.50 to 2.0% w/w; deairing agent, from 0.010 to 0.20% w/w; preserving agent, from 0.50 to 0.250% w/w; rheological additive, from 0.10 to 1.50% w/w; and water, from 1.70 to 10.2% w/w.

[00038] The product (2) is preferably obtained using a process that consists of three phases. The first phase involves the preparation of four separate mixtures, i.e. mixture (A), mixture (B), mixture (C) and mixture (D). In the second phase, such mixtures are mixed with one another, ultimately obtaining the mixture (II); the mixing order entails adding mixture (B) to mixture (A), then adding mixture (C) to the resulting mixture, and finally adding mixture (D). Finally, in the third phase, the mixture (II) obtained in the second phase is mixed with the organic compound (I).

[00039] The mixtures (A)-(D) are obtained simply by mixing the components in the specified w/w proportions of the mixture (II).

[00040] The first mixture, mixture (A), is prepared in two stages. In the first, the following components are simply mixed together: water, from 6.0 to 32.0% w/w; structuring agent, from 0.10 to 1.0% w/w; rheological additive, from 0.10 to 2.0% w/w; antifoam agent, from 0.050 to 0.50% w/w; fluidizing agent, from 2.0 to 8.0% w/w; preserving agent, from 0.050 to 0.30% w/w; and pH stabiliser, from 0.050 to 0.40% w/w.

[00041] In the second stage, the following are added to the resulting mixture: filler, from 3.0 to 10.0% w/w; and water, from 0.040 to 0.140% w/w.

[00042] The filler is added while mixing at high speed (approximately 650 to 750 rpm, when using a 400 mm long impeller) at a temperature of approximately 45-55°C and for approximately 10-20 minutes after adding the filler. At the end of this interval, in the third stage, the following are added: binder in aqueous emulsion, from 17.0 to 70.0% w/w; water, from 0.90 to 4.0% w/w.

[00043] Said binder may be, for instance, a mixture of an acrylic resin in an aqueous emulsion (e.g. from 10.0 to 40.0% w/w) and acrylic and methacrylic monomers in an aqueous emulsion (e.g. from 7.0 to 30.0% w/w).

[00044] The mixture (B) is prepared by mixing the following components together: hydrated potassium, sodium and aluminium silicate, from 1.0 to 5.0% w/w; and flakes of aluminium-potassium silicate with titanium dioxide, from 0.20 to 4.0% w/w.

[00045] The mixture (C) is prepared by mixing the following components: film formation agents, from 0.20 to 1.5% w/w; deairing agent, from 0.1 to 1.0% w/w; and water, from 3.0 to 25.0% w/w.

[00046] The mixture (D) is prepared by mixing the following components: structuring agent in emulsion, from 0.50 to 4.0% w/w; and water, from 2.0 to 17.0% w/w.

[00047] In the third phase, as described previously, the following components are mixed together (parts by weight): mixture (II), from 96.0 to 99.3% w/w, and pigmenting organic compound (I), from 0.70 to 4.0% w/w.

[00048] A further object of the present invention concerns the methods for applying the claimed painting system. Such method consists in the following stages:

1 ) treating the surface to paint with a water-based transparent fixative primer;

2) applying a coat of product (1);

3) leaving product (1 ) to dry, e.g. allowing an interval of at least 6 hours, and preferably 6-8 hours, after completing stage (2);

4) applying a second coat of product (1 );

5) leaving product (1) to dry, e.g. allowing an interval of at least 20 hours, and preferably 24 ore, after completing stage (4), 6) applying product (2) evenly and thickly to the dry surface in a layer least 60 μm, and preferably at least 70 μm thick.

[00049] The products (1) and (2) are applied using a short napped roller. The product (2) is preferably applied working downwards from above, then finishing the application at the bottom, and making the join with the previously applied area using the roller unloaded.

[00050] The following example is given here as a non-limiting illustration of the present invention. f 000511 EXAMPLE f000521 Product (1 ) r000531 First phase

[00054] The mixtures (i), (ii) and (iii) are prepared with the components listed below, for which the proportions are given in relation to the total weight of the end product, i.e. product (1 ).

[00055] Mixture (i):

[00056] 1st stage - the following components are mixed together: 16% w/w of water

0.30% w/w of structuring agent (sodium hydroxyethylcellulose), 1.0% w/w of ion sequestering agent (sodium hexametaphosphate), 0.30% w/w of dispersing agent (ammonium polyacrylate), 0.13% w/w of preserving agent (chloromethyl-methylisothiozolinone with formal N/O),

0.115% w/w of antifoam agent (amorphous silicon emulsified with synthetic hydrocarbons).

[00057] 2nd stage: the following components are added to the mixture coming from the first stage, one at a time and in the following order:

40.0% w/w of calcium carbonate with a particle size distribution from

10 μm to 40 μm, 75% of the granules having a particle size distribution around 10 μm and 25% of the granules having a particle size distribution around 40 μm;

0.280% w/w of pH stabilising agent (sodium hydroxide in aqueous solution); 0.40% w/w of water.

[00058] Calcium carbonate is added, mixing for approximately 15 minutes at a speed of 550 rpm using a 400 mm long impeller, at a temperature of 50° C.

[00059] Mixture (ii) - the following components are combined together:

20.0% w/w of binder (styrene and acrylic acid copolymer in aqueous emulsion);

15% w/w of water.

[00060] Mixture (iii) - the following components are combined together:

1.0% w/w of fluidizing agent (monoethylene 1 ,2-dihydroxypropane);

0.115% w/w of deairing agent (paraffin waxes in alkylated hydrocarbons);

0.10% w/w of preserving agent (chromomethyl-methylisothiozolinone- bromopol),

0.6% w/w of Theological additive (acrylic acid polymer).

[00061 ] Second phase

[00062] Mixture (ii) is mixed with mixture (i), and mixture (iii) is added to the resulting mixture, thus obtaining the product (1). r000631 Product (2) [00064] 1st phase

[00065] Mixtures (A), (B), (C) and (D) are prepared with the components listed below, for which the weight to weight proportions are given with reference to the total weight of the end product, i.e. mixture (II).

[00066] Mixture (A):

[00067] 1 st stage - the following components are mixed together: 16.0% w/w of water,

0.250% w/w of structuring agent (sodium hydroxyethyl cellulose), 0.250% w/w of colloidal magnesium, lithium and sodium silicate, 0.30% w/w of antifoam agent (amorphous silicon emulsified in synthetic hydrocarbons), 5.0% w/w of fluidizing agent (monoethylene 1 ,2-dihydroxypropane), 0.180% w/w of preserving agent (chloromethyl-methylisothiozolinone with formal N/O),

0.200% w/w of pH stabilising agent (aminomethyl propanol).

[00068] 2nd stage: the following components are added to the mixture coming from the previous stage, one at a time and in the following order: 7.50% w/w of filler in flakes (magnesium and aluminium silicate), 0.10% w/w of water.

[00069] The magnesium and aluminium silicate is added by mixing for approximately 15 minutes at a speed of 700 rpm, using a 400 mm long impeller, at a temperature of 50⁰C.

[00070] Mixture (B):

20.0% w/w of expanded riolite in granules with a particle size distribution from 10 μm to 110 μm, 50% of such granules having a particle size distribution from 30 μm to 70 μm,

1.50% w/w of a compound comprising aluminium-potassium silicate and titanium dioxide, said compound containing approximately 10% by weight of titanium dioxide and being in the form of flakes having dimensions from 70 μm to 700 μm.

[00071] Mixture (C):

1.0% w/w of film formation agents (2,2,4-trimethyl-i ,3-pentadiol monoisobutyrate),

1.0% w/w of deairing agent (polysiloxane)

20.0% w/w of water.

[00072] Mixture (D):

1.50% w/w of structuring agent in an emulsion (acrylic resin in anionic emulsion);

6.220% w/w of water.

[00073] Second phase

[00074] Mixture (A) is combined with mixture (B), then mixture (C) is added to the resulting mixture, and finally mixture (D) is also added, thus obtaining the mixture (II).

[00075] Third phase [00076] The product (2) is obtained by combining: 97.5% w/w of the mixture (II) with

2.5% w/w of polyethylene glycol terephthalate in flakes, the dimensions of which are between 180 and 200 μm long, and between 20 and 25 μm thick.

[00077] The resulting painting system can be applied to a surface pretreated with a coat of acrylic primer in aqueous dispersion. After the primer, two superimposed layers of product (1 ) are applied with a short napped roller (1 ). The second coat is applied 7 hours after applying the first coat. Twenty-four hours after applying the second coat, a layer of product (2) is applied using a short napped roller. The layer is spread evenly so as to obtain a thickness of 60-70 μm when the product is dry and it is applied downwards from above, always finishing off the join with the previously applied area using the roller unloaded.

[00078] The surface thus painted has particular lighting effects when viewed with lighting shed obliquely to the surface and to the touch it transmits a sense of "warmth" and an embossed effect.

Claims

1. A painting system comprising the following water-based products:

(1 ) a painting product (1) comprising (parts by weight): from 30 to 50% w/w of microcrystalline calcium carbonate with a particle size distribution from 5 μm to 60 μm, water q.s. to 100% w/w;

(2) a painting product (2) comprising (parts by weight): from 0.70 to 4.0% w/w of a pigmenting organic compound (I) chosen from among the salts and/or terephthalate acid esters, and from 96.0 to 99.30% w/w of a mixture (II) comprising (w/w): from 1.0 to 5.0% w/w of hydrated potassium, sodium and aluminium silicate with a particle size distribution from 5 μm to

150 μm; from 0.20 to 0.40% w/w of an aluminium-potassium silicate and titanium dioxide compound with a particle size distribution from

50 to 1000 μm, water q.s. to 100% w/w.

2. The system according to claim 1 wherein the calcium carbonate has a particle size distribution from 10 μm to 40 μm.

3. The system according to claim 1 or 2 wherein the hydrated potassium, sodium and aluminium silicate has a particle size distribution from 10 μm to 110 μm.

4. The system according to any of the previous claims, wherein the aluminium- potassium silicate and titanium dioxide compound is in the form of flakes and has dimensions ranging from 70 μm to 700 μm.

5. The system according to any of the previous claims, wherein the aluminium- potassium silicate and titanium dioxide compound has a titanium dioxide content coming between 5 and 15% by weight in respect of the weight of the compound.

6. A process for preparing the painting system according to claims from 1 to 5, wherein the painting products (1) and (2) are prepared by mixing.

7. The use of the painting system according to the claims from 1 to 5.

8. A method for applying the painting system according to the claims from 1 to 5 consisting in the completion of the following stages: 1 ) treating the surface to paint with a transparent water-based fixative primer;

2) applying a coat of the painting product (1);

3) allowing an interval of at least 6 hours to elapse after completing stage (2);

4) at the end of the time interval stated in stage (3), applying a second coat of the painting product (1);

5) allowing an interval of at least 20 hours to elapse after completing stage (3),

6) at the end of the time interval stated in stage (4), applying the product (2) evenly to a thickness of at least 60 μm; in said method, products (1 ) and (2) are applied using a short napped roller.

9. The application method according to claim 8, wherein the product (2) is applied working downwards from above, then finishing its application at the bottom, and making the join with the previously-applied area using the roller unloaded.