Coated Building Board

Abstract

The present invention relates to a coated building board comprising a color imaging layer for water-based inks and a method for making the coated building board. More particularly, the present invention relates to a coated building board in which the color imaging layer comprises a molecular sieve, particularly a microporous zeolite.

Description

[Technical Field]

[0001] The present invention relates to a coated building board comprising a color imaging layer for water-based inks and a method for making the coated building board. More particularly, the present invention relates to a coated building board wherein the color imaging layer comprises molecular sieves. [Background technology]

[0002] Various types of decorative building boards can be given color patterns, for example, by inkjet printing, which allows for efficient production and individual designs. Compared to solvent-based inks and UV inks, water-based inks have attracted more interest because they allow the application of pigments with higher weather resistance, which is suitable for exterior wall applications. Another important advantage is that water-based inks are more environmentally friendly.

[0003] On the other hand, there are challenges in implementing water-based inkjet printing because water-based inks are difficult to cure compared to solvent-based or UV inks. Therefore, water-based inks tend to penetrate into the substrate, especially if the substrate is porous, or spread over the surface if the substrate is non-porous. This leads to poor quality images.

[0004] In order to improve the color strength of images printed with water-based inks on decorative building boards, JP2007154433 (Patent Document 1) proposes an ink-receiving layer fixed on the surface of the building board. The ink-receiving layer is a water-based paint containing an extender pigment and a hygroscopic resin. JP2007167826 (Patent Document 2) discloses the use of such a coating composition to reduce ink consumption in ink-jet printing. JP2015051549 (Patent Document 3) proposes an ink-receiving layer containing polysiloxane to inhibit ink penetration into the ink-receiving layer and stably fix the ink.

[0005] JP2008273055 (Patent Document 4) discloses a coating composition for an ink-receiving layer, which contains a mica filler in an amount of 20 to 80% by weight of the solid content of the coating composition in order to enhance the durability of the coating layer.

[0006] JP2008063832 (Patent Document 5) provides a decorative building board that enhances ink fixation to the ink-receiving layer and prevents deterioration of the strength of this layer. To achieve the desired effect, the ink-receiving layer contains a filler with a high aspect ratio of 3 to 70 that can be finely divided on the surface of the layer. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] JP2007154433 [Patent Document 2] JP2007167826 [Patent Document 3] JP2015051549 [Patent Document 4] JP2008273055 [Patent Document 5] JP2008063832 [Non-patent literature]

[0008] [Non-Patent Document 1] “Atlas of Zeolite Framework Types” (Baerlocher et al., Elsevier, Sixth Revised Edition, 2007) Summary of the Invention [Problem to be solved by the invention]

[0009] The problem to be solved by the present invention is to provide a building board that can be used as a base material for high-quality images printed with water-based inks. Specifically, the resolution, color strength, and image stability of the printed image are improved. To achieve the object of the present invention, the penetration of the water-based ink into the building board is reduced to avoid low color strength, and color bleeding is avoided to achieve improved resolution of the printed pattern. [Means for solving the problem]

[0010] The above problems are solved by a color imaging layer (ink-receiving layer) containing a molecular sieve.

[0011] Molecular sieves are porous materials with pores of relatively uniform size. The pore diameters of molecular sieves are similar in size to small molecules, and therefore, unlike small molecules, they cannot adsorb large molecules, such as water. The diameter of molecular sieves is measured in angstroms (Å) or nanometers (nm). Molecular sieves are classified into microporous materials with pore sizes less than 2 nm (20 Å), mesoporous materials with pore sizes between 2 nm and 50 nm (20-500 Å), and macroporous materials with pore sizes greater than 50 nm (500 Å). Macroporous materials with pore sizes greater than 200 nm (2000 Å) are not considered molecular sieves within the meaning of the present invention.

[0012] The coated building board of the present invention is obtained by an aqueous coating composition comprising an acrylic emulsion and a molecular sieve, which composition is allowed to cure on the surface of the building board.

[0013] Therefore, one aspect of the present invention is a method for producing a coated building board including a color imaging layer, comprising the steps of: a) the following ingredients: i) 20% to 80% by weight of the coating composition of an acrylic polymer emulsion, and ii) 0.2% to 20% by weight of the coating composition of molecular sieves; an aqueous coating composition comprising applied to at least a portion of the surface of the building board; and b) curing the coating composition; The method includes:

[0014] To achieve the desired effects of the present invention, the use of microporous molecular sieves is preferred. Preferred molecular sieves have a narrow pore size distribution, where at least 90% of the pores in the molecular sieve have a pore size between 0.1 nm and 2 nm, more preferably between 0.2 nm and 0.8 nm.

[0015] The microporous molecular sieve can be selected, for example, from the group of aluminosilicate inorganic materials (zeolites), phosphorus-modified small pore zeolites, porous glass, activated carbon, and small pore clays such as montmorillonite.

[0016] Preferred molecular sieves are capable of adsorbing molecules having an effective diameter of 0.5 nm or less, such as water. Useful sieves are capable of adsorbing at least 5% by weight of water, more preferably greater than 10% by weight of water, at 20° C., relative to the weight of the molecular sieve.

[0017] Preferred microporous molecular sieves are selected from the group of zeolites, particularly preferred are 3 Å, 4 Å or 5 Å zeolites.

[0018] Suitable zeolites have the general formula (I): M n+ x / n ·[(AlO2) - x (SiO2) y ]·zH2O (I) [In the formula, n is 1, 2, 3 or 4, preferably n is 1 or 2; M is selected from the group of monovalent, divalent, trivalent or tetravalent metals or mixtures thereof, preferably M is selected from the group of alkali metals, alkaline earth metals and mixtures thereof, most preferably metals from the group potassium, sodium, magnesium and calcium; x is between 1 and 10, preferably between 1 and 3, and The x / y ratio of the zeolite of formula (I) is between 1 and 5, more preferably between 1 and 3, and most preferably said ratio is approximately 2, which means between 1.8 and 2.2. The water content of the zeolite can vary over a wide range. For example, water can be removed from the zeolite by heating without destroying the zeolite structure. Conversely, zeolites can adsorb water until the compound's capacity is exhausted. Dry zeolites of the preferred zeolite type (x and x / y in the range of 1 to 3) can, for example, adsorb up to 30% by weight of water relative to the weight of the zeolite. The water content z of the zeolite of formula (I) is typically in the range of 0 to 50, preferably between 1 and 30. For preferred zeolites with x in the range of 1 to 3 and x / y ratio in the range of 1 to 3, z is typically less than 10.

[0019] The most preferred molecular sieves of the zeolite type are 3 Å, 4 Å or 5 Å zeolite sieves.

[0020] A typical 3 Å sieve has the following chemical formula: x'K2O·x''Na2O·Al2O3·ySiO2·zH2O [In the formula, x' and x'' are in the range of 0.3 to 0.7, and x' and x'' are 1; y is in the range of 1.8 to 2.2, preferably y is 2, and z is less than 8, and z is preferably in the range of 3 to 6, typically 4.5. A typical 4 Å sieve has the following chemical formula: Na2O·Al2O3·ySiO2·zH2O [In the formula, y is in the range of 1.8 to 2.2, preferably y is 2, and z is less than 8, and z is preferably in the range of 3 to 6, typically 4.5. A typical 5 Å sieve has the following chemical formula: x'CaO·x''Na2O·Al2O3·ySiO2·zH2O [In the formula, x' is in the range of 0.6 to 0.8, x'' is in the range of 0.2 to 0.4, and x'+x'' is 1; y is in the range of 1.8 to 2.2, preferably y is 2, and z is less than 8, and z is preferably in the range of 3 to 6, typically 4.5. A wide variety of microporous molecular sieves are commercially available, including 3Å, 4Å, and 5Å zeolites. However, 4Å sieves can be prepared by mixing aqueous solutions of sodium silicate and sodium aluminate at 80°C. The sieves are then activated by baking at 400°C. 3Å and 5Å sieves can be prepared starting from 4Å sieves via cation exchange of sodium for cations (for 3Å sieves) or sodium for calcium for 5Å sieves.

[0021] An example of a mesoporous molecular sieve is silicon dioxide. An example of a macroporous molecular sieve is a porous silica compound having a pore size of 200 to 1000 Å.

[0022] The pore size of a molecular sieve depends on the size of the lattice of the material itself, which is primarily determined by the size of the cations. The structures of a wide variety of zeolites, including the channel (pore) sizes, are summarized in "Atlas of Zeolite Framework Types" (Baerlocher et al., Elsevier, Sixth Revised Edition, 2007) (Non-Patent Document 1).

[0023] Preferred molecular sieves are capable of adsorbing molecules having an effective diameter of 0.5 nm or less, such as water. Useful sieves are capable of adsorbing at least 5% by weight of water, more preferably greater than 10% by weight of water, compared to the weight of the molecular sieve.

[0024] The molecular sieve is preferably applied to the aqueous coating composition in the form of a powder. Preferred powders have an average particle size in the range of 0.1 μm to 250 μm, preferably between 1 μm and 50 μm. At least 80%, especially at least 90%, of the particles should have an average size within this range.

[0025] The size distribution of molecular sieve particles can be determined by laser diffraction analysis. The average diameter can be determined by laser light scattering, for example, using a Horiba LA940 or Malvern Mastersizer using the "Mie Scattering Theory" evaluation method. For particles with axes of different lengths, such as particles with an elliptical or discoidal shape, the longest axis determines the average diameter. The particles of the present invention preferably have a narrow particle size distribution with a Gaussian shape. Preferably, the standard deviation of the particle size distribution is between 10% and 120% of the average diameter. More preferably, the standard deviation is between 20% and 90%.

[0026] The coating composition further comprises an acrylic emulsion comprising an acrylic polymer obtainable by free radical polymerization of an acrylic monomer composition, wherein the acrylic monomer is selected from the group consisting of acrylates, methacrylates, alkyl acrylates, alkyl methacrylates, hydroxyalkyl acrylates, hydroxyalkyl methacrylates, epoxyalkyl acrylates, epoxyalkyl methacrylates, acrylonitrile, methacrylonitrile, acrylamides, methacrylamides, acrylic acid, and mixtures thereof, optionally with an ethylenically unsaturated comonomer.

[0027] Preferred acrylic polymers are derived from monomers from the group consisting of acrylates, methacrylates, (C1-C4) alkyl acrylates, (C1-C4) alkyl methacrylates, acrylic acid and mixtures thereof, optionally and ethylenically unsaturated comonomers.

[0028] Preferred comonomers are selected from the group of (C1-C6) alkylenes, in particular ethylene, propylene and butylene, and styrene.

[0029] The acrylic polymer emulsion also includes an emulsion of an acrylic silicone resin.

[0030] The acrylic monomer composition preferably comprises at least 50% by weight of an acrylic monomer and less than 50% by weight of an ethylenically unsaturated comonomer.

[0031] The content of the acrylic polymer in the acrylic emulsion is 5 to 75% by weight, preferably between 10% and 70% by weight, and particularly preferably between 20% and 60% by weight.

[0032] The water content of the acrylic polymer emulsion is between 25% and 75% by weight, preferably between 30% and 60% by weight.

[0033] The aqueous coating composition containing the acrylic polymer emulsion and the molecular sieve preferably contains 1 to 10% by weight of the molecular sieve, and the amount of the acrylic polymer emulsion is preferably in the range of 25 to 60% by weight, more preferably 30 to 55% by weight, based on the total weight of the aqueous coating composition.

[0034] The weight ratio of the microporous sieve to the acrylic polymer in the aqueous coating composition is preferably 1:1 to 1:100, more preferably 1:1.5 to 1:20, and most preferably 1:2 to 1:10.

[0035] The aqueous coating composition may contain optional additives. Examples of useful additives include dispersants, wetting agents, thickeners, antifoaming agents, fillers, film-forming agents, matting agents, neutralizing agents, or biocides. The additives can be applied to the acrylic polymer emulsion or to the aqueous coating composition containing the emulsion.

[0036] Conventional additives include wetting or dispersing agents such as sodium, potassium, or ammonium polyphosphate; alkali metal or ammonium salts of polyacrylic or polymaleic acid; styrene-maleic anhydride copolymers, polyphosphonates, amino alcohols such as 2-amino-2-methylpropanol, etc. Dispersing or wetting agents are preferably used in an amount of up to 2% by weight, based on the total weight of the aqueous coating composition.

[0037] Typically, the acrylic polymer in the acrylic polymer emulsion is self-emulsifying. Therefore, the amount of additional dispersant can be small. The content of the dispersant in the aqueous coating composition is less than 5 wt %, preferably in the range of 0 to 1 wt %, based on the total weight of the aqueous coating composition.

[0038] Antifoam additives are, for example, fatty acid alkyl ester alkoxylates, silicone oils, organic polysiloxanes such as polydimethylsiloxanes, polyether-modified polysiloxanes, silanized silica, paraffins (including paraffin oils), waxes, polyethers such as polyethylene glycol, polypropylene glycol or EO / PO copolymers, and mixtures thereof.

[0039] Antifoaming agents are typically used in amounts of less than 5% by weight, particularly in amounts ranging from 0 to 2% by weight, based on the total weight of the aqueous coating composition.

[0040] The matting agent may be present in the aqueous coating composition in an amount of 0 to 15 wt. % based on the total weight of the coating composition. A content of matting agent of 1 to 10 wt. % is preferred. Suitable matting agents are silica dioxide and waxes.

[0041] Thickeners that can be used in the aqueous coating composition are, for example, cellulose derivatives such as methylcellulose, hydroxyethylcellulose and carboxymethylcellulose, as well as casein, gum arabic, starch, sodium alginate, polyvinyl alcohol, polyvinylpyrrolidone, styrene / maleic anhydride polymers, hydrophilically modified polyether urethanes, hydrophobically modified acrylic acid copolymers (HASE), sodium polyacrylate, organosilicones, and polyether polyols.

[0042] Water-soluble copolymers based on acrylic acid and (meth)acrylic acid, such as acrylic acid / acrylamide and (meth)acrylic acid / acrylic acid ester copolymers, also have thickening properties.

[0043] Inorganic thickeners such as bentonite may also be used.

[0044] Particular preference is given to using thickeners from the group of acrylic polymers and polyurethanes.

[0045] The amount of thickener based on the total weight of the coating composition is less than 10% by weight, preferably less than 5% by weight.

[0046] Suitable film-forming agents include, for example, polyvinylpyrrolidone, glycol ethers, glycol esters, or combinations thereof. Examples of glycol ethers include ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, ethylene glycol monoisopropyl ether, ethylene glycol monobutyl ether, ethylene glycol monophenyl ether, ethylene glycol monohexyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol mono-n-butyl ether, diethylene glycol mono-n-hexyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monobutyl ether, propylene glycol monohexyl ether, polyethylene glycol ether, polypropylene glycol ether, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, and ethylene glycol dibutyl ether. Examples of glycol ethers include ethylene glycol methyl ether acetate, ethylene glycol monoethyl ether acetate, ethylene glycol monobutyl ether acetate, and propylene glycol methyl ether acetate.

[0047] The content of the film-forming additive is usually less than 10% by weight based on the total weight of the aqueous coating composition, with an amount in the range of 0.5 to 5% by weight being preferred.

[0048] The filler that can be used is known to those skilled in the art.Preferred filler is silicate, such as kaolin, talc, mica, magnesite, alkaline earth metal carbonate, such as calcite, chalk, dolomite, alkaline earth metal sulfate, such as calcium sulfate, and silica.These fillers can be used as individual components or as filler mixtures.Generally, finely divided fillers are preferred.

[0049] The aqueous coating composition optionally contains one or more cosolvents. The cosolvents may be part of the additive composition. A small amount of cosolvent can be used to improve the solubility of the components of the aqueous coating composition. The amount of cosolvent should be less than 10 wt % based on the total weight of the coating composition. Preferably, the content of cosolvent is less than 5 wt %.

[0050] Suitable are water-miscible cosolvents such as methanol, ethanol, propanol, butanol, benzyl alcohol, ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, glycerol, polyethylene glycol, polypropylene glycol, and the monomethyl or dimethyl ethers of ethylene glycol or propylene glycol.

[0051] For some applications, it is desirable to adjust the pH value of the aqueous coating composition. Conventional neutralizing agents can be used to adjust the pH value. Examples of neutralizing agents are sodium hydroxide, potassium hydroxide, or amine derivatives. For most applications, a pH value in the range of 7 to 11 is desired. The neutralizing agent is added to the coating composition until the desired pH value is achieved.

[0052] The aqueous coating composition may further comprise a pigment. The pigment may be selected from inorganic or organic pigments. Pigments that can be used are all pigments known to those skilled in the art for emulsion paints. Preferred pigments are, for example, titanium dioxide, preferably in the rutile form, barium sulfate, zinc oxide, zinc sulfide, basic lead carbonate, antimony trioxide, and lithopone (zinc sulfide and barium sulfate). However, the aqueous formulation may also contain colored pigments, such as iron oxides, carbon black, graphite, luminescent pigments, zinc yellow, zinc green, ultramarine, manganese black, antimony black, or manganese violet. Organic pigments are, for example, azo dyes, quinacridones, phthalocyanines, isoindolinones, sepia, gamboge, indigo, anthraquinoid and indigoid dyes, and dioxazines, as well as metal complex pigments.

[0053] The most preferred pigments are titanium dioxide, zinc oxide, barium sulfate and lithopone.

[0054] Pigments can be added to the aqueous coating composition in amounts up to 30% by weight, based on the total weight of the aqueous coating composition. Light-colored pigments are typically added in larger amounts, while dark-colored pigments are typically added in smaller amounts, up to 15% by weight.

[0055] Preferably, light pigments such as titanium dioxide, zinc oxide, barium sulfate and lithopone are added to the coating composition in an amount of 5 to 25% by weight.

[0056] These pigments can be blended with extender pigments such as silica, barium carbonate, calcium carbonate, alumina, aluminum hydroxide, diatomaceous earth, and the like.

[0057] The coating composition may optionally contain, in addition to the acrylic polymer, further polymers. Suitable optional polymers may be selected from the group of hygroscopic polymers. For example, polyvinyl acetate, polyvinyl alcohol, and polyurethane may be optionally added.

[0058] These optional polymers can be added in an amount of up to 50 wt % based on the total weight of the aqueous coating composition.The content of optional polymers in the coating composition is preferably between 0 wt % and 30 wt %, particularly between 5 wt % and 25 wt %.Particularly preferred are coating compositions that do not contain optional polymers or whose content of optional polymers is less than 5 wt %.

[0059] The aqueous coating composition can be obtained by adding the molecular sieve to the acrylic polymer emulsion. The molecular sieve can be simply incorporated into the acrylic polymer emulsion by stirring until the sieve is completely dispersed. Additives and pigments can be added, usually in small increments, with stirring.

[0060] In addition to the water already present in the acrylic polymer emulsion, additional water can be added to the aqueous coating composition, if appropriate. However, the overall water content in the coating composition should be less than 80% by weight. Preferably, the overall water content ranges from 25% to 65% by weight.

[0061] The aqueous coating composition can be applied to the surface of the building board by a spray device, such as a spray gun. Alternatively, the coating composition can be brushed onto the surface or applied using a doctor blade.

[0062] Typically, the aqueous coating composition is applied in a coating amount of 10 g / m 2 to 300g / m 2 in amounts up to, preferably 20 g / m 2 from 200 g / m 2 The amount of the applied product is in the range of 100 to 1500 mg / kg.

[0063] The aqueous coating composition applied to the building board is then cured to obtain a color-imaging layer on the surface of the building board. Curing can be achieved by drying the coating at a temperature between 80°C and 300°C for 1 minute to 1 hour. The coating is sufficiently dry when the resulting color-imaging layer is capable of capturing water-based ink. The coated building board may be dried in an oven. Drying at a temperature between 150°C and 250°C for 2 to 150 minutes is preferred.

[0064] The thickness of the color imaging layer on the building board is usually between 5 μm and 500 μm, preferably between 10 μm and 200 μm.

[0065] A wide range of building materials can be used as the building board as long as the color imaging layer can be sufficiently fixed on the surface. For example, cement boards, gypsum boards, ceramic boards, metal boards, wood boards, or polymer resin boards are suitable building boards. Cement or gypsum building boards are preferably used. The adhesion of the color imaging layer on these boards is excellent. Fiber-reinforced building boards, especially cement boards containing glass fibers or polymer fibers, are also suitable.

[0066] The coated building board preferably includes a sealing layer or a primer layer. The sealing layer or primer layer can be applied to the surface of the building board. Thus, the surface of the building board to which the aqueous coating composition is applied is formed by such a layer. More preferably, the primer layer is applied to provide a background color, especially when a pigment-free color imaging layer is subsequently applied. For example, a building board including a sealing layer and a white primer layer is particularly useful. Sealing compositions and primer compositions, especially for cement or gypsum plates, are known in the prior art.

[0067] Conventional primer compositions include, for example, aqueous emulsions of polyvinyl acetate, copolymers of vinyl acetate and ethylene, copolymers of acrylic esters and styrene, and aqueous solutions of polyvinyl alcohol. Typical sealers are water- or solvent-based acrylic resins, epoxy / urethane systems, silanes, silicates, siliconates, siloxanes, and the like.

[0068] Yet another aspect of the present invention is a coated building board comprising a color imaging layer of the cured coating composition described above.

[0069] The color imaging layer applied to at least a portion of the surface of the coated building board of the present invention preferably comprises, after curing, 30% to 95% by weight of an acrylic polymer and 0.5 to 50% by weight of a layer of molecular sieve.

[0070] The water content of the color imaging layer is significantly reduced compared to that of the aqueous coating composition. The water content of the color imaging layer is usually less than 10 wt. % of the weight of the molecular sieve, preferably less than 5 wt. %, and particularly preferably less than 3 wt. %. Typically, the water content is in the range of 0.1 wt. % to 2 wt. %.

[0071] The weight ratio of molecular sieve to acrylic polymer in the color imaging layer of the coated building board is preferably in the range of 1:1 to 1:100, more preferably in the range of 1:1.5 to 1:20, and most preferably in the range of 1:2 to 1:10.

[0072] A preferred coated building board of the present invention comprises: a) 30 to 80% by weight of the acrylic polymer; b) 5 to 40 wt. % of said molecular sieve; c) optionally 0.2 to 2 wt. % of an antifoaming agent; d) optionally 0.2 to 4 wt. % of a dispersant; e) optionally 0 to 15 wt. % of a matting agent; f) optionally 3 to 10 wt. % of a film-forming agent; g) optionally 0.5 to 8 wt. % of a thickener; h) optionally up to 0.5% by weight of a biocide, and i) optionally up to 0.5% by weight of a neutralizing agent; The color imaging layer comprises:

[0073] Another preferred embodiment of the coated building board is a) 30 to 75% by weight of the acrylic polymer; b) 5 to 35 wt. % of said molecular sieve; c) optionally 0.2 to 2 wt. % of an antifoaming agent; d) optionally 0.2 to 4 wt. % of a dispersant; e) optionally 0 to 15 wt. % of a matting agent; f) optionally 3 to 10 wt. % of a film-forming agent; g) optionally 0.5 to 8 wt. % of a thickener; h) optionally up to 0.5% by weight of a biocide, i) optionally up to 0.5% by weight of a neutralizing agent, and j) optionally 5 to 30 wt. % of a pigment; The color imaging layer comprises:

[0074] Preferred antifoaming agents, dispersants, matting agents, film-forming agents, thickeners and neutralizing agents are as described above.

[0075] The coated building board is particularly suitable for printing color patterns or images onto the color imaging layer using water-based inks. The water-based inks can be printed directly onto the color imaging layer, for example, by inkjet printing. The printed patterns can be easily personalized. The coated building board is suitable for DIY (do-it-yourself) printing.

[0076] When water-based ink is applied to the color imaging layer, the ink is quickly fixed and color bleeding is greatly reduced. The resolution of the printed pattern or image is improved. Furthermore, rapid penetration of water-based ink into the color imaging layer is avoided, which contributes to high color strength.

[0077] Without being bound by theory, the desired effect is achieved by the accelerated water adsorption from the water-based ink by the molecular sieve, and at the same time, the penetration of the colorants and pigments provided as components of the water-based ink into the color imaging layer is greatly delayed, which results in low color bleeding and high color strength.

[0078] The color imaging layer is particularly useful for applying water-based inks having a water content of 40 to 70% by weight and a pigment content ranging from 3 to 20% by weight. Typical water-based inks further contain up to 40% by weight of a humectant, such as glycerin, propylene glycol, etc., up to 2% by weight of a surfactant, such as a polyoxyethylene alkyl ether, and a pH adjuster. Optionally, the water-based ink can contain up to 10% by weight of an acrylic resin.

[0079] Therefore, yet another aspect of the present invention is the use of a building board comprising a color imaging layer as described herein as a base material for ink jet printing with water-based inks. [Example]

[0080] Example 1 (E1): 40 parts by weight of deionized water, 45 parts by weight of acrylic emulsion (Mowilith DN 7070 manufactured by Archroma Co. Ltd.), 0.3 parts by weight of antifoaming agent (BYK-022 manufactured by BYK Additives & Instruments), 0.15 parts by weight of dispersing agent (BYK-190 manufactured by BYK Additives & Instruments), 3.5 parts by weight of silica dioxide (SYLOID W 300 manufactured by W.R. Grace & Co.), and 2.7 parts by weight of wax powder (Ceridust 8090 TP manufactured by Clariant Chemicals Ltd) were mixed by a disperser at a shear rate of 1000 rpm for 30 minutes, and then 3 parts by weight of film-forming agent (DOWANOL 1000 manufactured by Dow Chemical) were added. TMDPnB), 0.5 parts by weight of a thickener (Mowiplus TK-582, manufactured by Archroma Co. Ltd.), and 0.075 parts by weight of a biocide (Acticide LA0614, manufactured by Thor Chemie) were blended, and approximately 0.075 parts by weight of 2-amino-2-methyl-1-propyl alcohol (AMP95, manufactured by Dow Chemical) was gradually added as a neutralizer to adjust the pH to 8-10. The mixture was dispersed in a disperser at a shear rate of 1500 rpm for 60 minutes. Finally, 4.7 parts by weight of molecular sieves (SYLOSIV A3, manufactured by W.R. Grace & Co.) were blended into the mixture at a shear rate of 1500 rpm for 30 minutes until the molecular sieves were completely dispersed to form the coating composition.

[0081] The coating composition was applied at 80 g / m 3 and cured in an oven at a temperature of 200°C for 3 minutes to form a color imaging layer. The fiber cement board was pretreated with a sealing coating and a white primer coating.

[0082] Example 2 (E2): 30 parts by weight of deionized water, 40 parts by weight of acrylic emulsion (Neocryl XK-87 manufactured by DSM NeoResin), 0.25 parts by weight of antifoaming agent (BYK-028 manufactured by BYK Additives & Instruments), 0.13 parts by weight of dispersing agent (BYK-190 manufactured by BYK Additives & Instruments), 3 parts by weight of SYLOID W 300 (manufactured by W.R. Grace & Co.), and 2.2 parts by weight of ACEMATT TS100 (manufactured by Evonik) were mixed by a disperser at a shear rate of 1000 rpm for 30 minutes, and then 15 parts by weight of titanium dioxide (Colanyl White TQ-CN manufactured by Clariant Chemicals Ltd), 2.5 parts by weight of film-forming agent (DOWANOL 100 manufactured by Dow Chemical) were added. TMDPnB), 0.4 parts by weight of a thickener (Mowiplus TK-582, manufactured by Archroma Co. Ltd.), and 0.06 parts by weight of a biocide (Acticide LA0614, manufactured by Thor Chemie) were blended, and approximately 0.06 parts by weight of 2-amino-2-methyl-1-propyl alcohol (AMP95, manufactured by Dow Chemical) was gradually added as a neutralizer to adjust the pH to 8-10. The mixture was dispersed in a disperser at a shear rate of 1500 rpm for 60 minutes. Finally, 6.4 parts by weight of molecular sieves (SYLOSIV A3, manufactured by W.R. Grace & Co.) were blended into the mixture at a shear rate of 1500 rpm for 30 minutes until the molecular sieves were completely dispersed to form the coating composition.

[0083] The coating composition was applied at 140 g / m 3 and cured in an oven at a temperature of 200° C. for 3 minutes to form a color imaging layer. The fiber cement board was pretreated with a sealing coating.

[0084] Example 3 (E3): 30 parts by weight of deionized water, 53.1 parts by weight of acrylic emulsion (Neocryl XK-87 manufactured by DSM NeoResin), 0.34 parts by weight of antifoaming agent (BYK-022 manufactured by BYK Additives & Instruments), 0.17 parts by weight of dispersing agent (Dispersogen LFH manufactured by Clariant Chemicals Ltd), 3 parts by weight of SYLOID W 300 (manufactured by W.R. Grace & Co.), 1.3 parts by weight of ACEMATT TS100 (manufactured by Evonik), and 2.7 parts by weight of Ceridust 8090 TP (manufactured by Clariant Chemicals Ltd) were mixed in a disperser at a shear rate of 1000 rpm for 30 minutes, and then 4 parts by weight of film-forming agent (Texanol manufactured by Eastman Chemical), 0.6 parts by weight of thickener (Acrysol ASE-60 manufactured by Dow Chemical), 0.24 parts by weight of biocide (Acticide manufactured by Thor Chemie) were added. The mixture was blended with 4.4 parts by weight of molecular sieves (SYLOSIV A3 manufactured by W.R. Grace & Co.) at a shear rate of 1500 rpm for 30 minutes until the mixture was completely dispersed and the coating composition was formed.

[0085] This coating composition was applied at 100 g / m 3 and cured in an oven at a temperature of 200°C for 3 minutes to form a color imaging layer. The fiber cement board was pretreated with a sealing coating and a white primer coating.

[0086] Example 4 (E4): 35 parts by weight of deionized water, 47 parts by weight of acrylic emulsion (Mowilith DN 7070 manufactured by Archroma Co. Ltd.), 0.3 parts by weight of antifoaming agent (BYK-022 manufactured by BYK Additives & Instruments), 0.15 parts by weight of dispersing agent (BYK-190 manufactured by BYK Additives & Instruments), and 5.5 parts by weight of silica dioxide (SYLOID W 300 manufactured by W.R. Grace & Co.) were mixed by a disperser at a shear rate of 1000 rpm for 30 minutes, and then 3 parts by weight of film-forming agent (DOWANOL manufactured by Dow Chemical) were added. TM DPnB), 0.5 parts by weight of a thickener (Mowiplus TK-582, manufactured by Archroma Co. Ltd.), and 0.075 parts by weight of a biocide (Acticide LA0614, manufactured by Thor Chemie) were blended, and approximately 0.075 parts by weight of 2-amino-2-methyl-1-propyl alcohol (AMP95, manufactured by Dow Chemical) was gradually added as a neutralizer to adjust the pH to 8-10. The mixture was dispersed in a disperser at a shear rate of 1500 rpm for 60 minutes. Finally, 8.4 parts by weight of molecular sieves (SYLOSIV A3, manufactured by W.R. Grace & Co.) were blended into the mixture at a shear rate of 1500 rpm for 30 minutes until the molecular sieves were completely dispersed to form the coating composition.

[0087] The coating composition was applied at 20 g / m 3 and cured in an oven at a temperature of 150°C for 10 minutes to form a color imaging layer. The fiber cement board was pretreated with a sealing coating and a white primer coating.

[0088] Comparative example 1 (CE1): The fiber cement board was pretreated with a sealing coat and a white base coat, but no color imaging layer was applied.

[0089] Comparative Example 2 (CE2): Example 1 was repeated in the absence of molecular sieves to produce a molecular sieve-free coating composition. The resulting coating composition was applied at 80 g / m 3 and cured in an oven at a temperature of 200°C for 3 minutes to form a color imaging layer. The fiber cement board was pretreated with a sealing coat and a white primer coat as described in CE1.

[0090] Comparative Example 3 (CE3): Example 1 was repeated, replacing the molecular sieves with an equal amount of bentonite.

[0091] Comparative Example 4 (CE4): Commercially available decorative acrylic paint was applied at 80 g / m 3 and cured in an oven at a temperature of 200°C for 3 minutes to form a color imaging layer. The fiber cement board was pretreated with a sealing coating and a white primer coating.

[0092] Performance evaluation: The resulting building boards were placed under an ink jet device equipped with four colors of water-based inks, namely cyan, magenta, yellow, and black. The ejection and pause of the four inks from the nozzles was individually controlled by a control unit. Ink jet printing was performed by directly printing pre-designed images onto these building boards. The building boards were then dried in an oven at a temperature of 200°C for 3 minutes to harden the imaging layer. Preferably, a transparent top coating is sprayed onto the hardened imaging layer for protection. The resulting images were visually evaluated. The evaluation criteria were as follows: *Color intensity from 1 (very low) to 5 (high) *Resolution ranging from 1 (very blurry and fuzzy, image is difficult to recognize) to 5 (image is clear and sharp) *Image stability ranging from 1 (easily blurred when rubbed with a finger) to 5 (image remains stable even when rubbed or scratched)

[0093] [Table 1]

[0094] By magnifying the image by 60 times, the appearance of the ink dots can be evaluated.

[0095] In Example CE1, where no imaging layer was applied, the resulting ink dots were very small and thin with large spacing. The ink dots were absorbed by the porous base material, resulting in low color strength and poor resolution. In Examples CE2 and CE4, a cured coating without molecular sieves was applied. Penetration of the ink dots into the coating layer was avoided, and therefore color strength was greatly improved. However, because aqueous inks are difficult to cure, the ink dots tend to merge with each other and become irregular, resulting in a blurred image. The ink dots obtained in Examples E1 to E4 appeared clear and densely granular, and no color bleeding was observed. The images on the building boards containing the color imaging layer according to the present invention (E1 to E4) were significantly clearer than those on the building boards of Examples CE1 to CE4. The molecular sieve further improved the fixation of the ink dots and the stability of the image against rubbing and scratching. While this application is directed to the invention set forth in the claims, the disclosure of this application also includes: 1. A method for producing a coated building board containing a color imaging layer, comprising: a) applying an aqueous coating composition to at least a portion of a surface of a building board, said aqueous coating composition comprising the following components: i) 20% to 80% by weight of the coating composition of an acrylic polymer emulsion, and ii) 0.2% to 20% by weight of the coating composition of molecular sieves; and b) curing the coating composition; The method comprising: 2. The method according to claim 1, wherein the molecular sieve is a microporous molecular sieve, preferably a microporous molecular sieve selected from the group consisting of zeolites. 3. The method according to claim 1 or 2, wherein at least 90% of the pores of the molecular sieve have a pore size between 0.1 nm and 2 nm, and preferably the molecular sieve is a 3 Å, 4 Å or 5 Å zeolite. 4. The method according to any one of 1. to 3., wherein the acrylic polymer emulsion comprises an acrylic polymer obtainable by free radical polymerization of an acrylic monomer composition, wherein the acrylic monomer is selected from the group consisting of acrylates, methacrylates, alkyl acrylates, alkyl methacrylates, hydroxyalkyl acrylates, hydroxyalkyl methacrylates, epoxyalkyl acrylates, epoxyalkyl methacrylates, acrylonitrile, methacrylonitrile, acrylamides, methacrylamides, acrylic acid, and mixtures thereof, and optionally, ethylenically unsaturated comonomers. 5. The method according to claim 4, wherein the acrylic monomer composition comprises at least 50% by weight of an acrylic monomer and less than 50% by weight of an ethylenically unsaturated comonomer. 6. The method according to any one of 1 to 5 above, wherein the water content of the acrylic polymer emulsion is between 25% and 75% by weight. 7. The method according to any one of 1. to 6. above, wherein the aqueous coating composition comprises a film-forming agent selected from the group consisting of glycol ethers or glycol esters or combinations thereof. 8. The method according to any one of 1. to 7., wherein the aqueous coating composition comprises up to 50% by weight of an additional polymer selected from the group consisting of polyvinyl acetate, polyvinyl alcohol, and polyurethane. 9. The method according to any one of 1. to 8., wherein the aqueous coating composition comprises a dispersant, a thickener, a filler, an antifoaming agent, a neutralizing agent, a biocide, a matting agent and / or a pigment. 10. A coated building board comprising a color imaging layer of the cured coating composition described in any one of 1. to 9. above on at least a portion of the surface of the building board. 11. A coated building board comprising a color imaging layer on at least a portion of its surface, the color imaging layer comprising 30% to 95% by weight of a layer of an acrylic polymer and 0.5% to 50% by weight of a layer of a molecular sieve. 12. The coated building board according to claim 11, wherein the weight ratio of the molecular sieve to the acrylic polymer in the color imaging layer is 1:1 to 1:20. 13. The coated building board according to claim 11 or 12, wherein the molecular sieve is a microporous sieve, preferably a zeolite, most preferably a 3 Å, 4 Å, or 5 Å zeolite, or a mixture thereof. 14. The coated building board according to any one of 10 to 13 above, wherein the building board is a cement plate, a gypsum plate, a ceramic plate, a metal plate, a wood plate or a polymer resin plate. 15. Use of the building board according to any one of the above 10 to 14 as a base material for ink jet printing using water-based ink.

Claims

1. 1. A method for producing a coated building board containing a color imaging layer, comprising: a) applying an aqueous coating composition to at least a portion of a surface of a building board, said aqueous coating composition comprising the following components: i) 20% to 80% by weight of the coating composition of an acrylic polymer emulsion, and ii) 0.2% to 20% by weight of the coating composition of molecular sieves; and b) curing the coating composition; Including, The molecular sieve is a microporous molecular sieve, and at least 90% of the pores of the molecular sieve have a pore size between 0.1 nm and 2 nm; The method.

2. 10. The method of claim 1, wherein the molecular sieve is a microporous molecular sieve selected from the group consisting of zeolites.

3. The method of claim 2, wherein the molecular sieve is a 3 Å, 4 Å or 5 Å zeolite.

4. 4. The method according to any one of claims 1 to 3, wherein the acrylic polymer emulsion comprises an acrylic polymer obtainable by free radical polymerization of an acrylic monomer composition, wherein the acrylic monomer is selected from the group consisting of acrylates, methacrylates, alkyl acrylates, alkyl methacrylates, hydroxyalkyl acrylates, hydroxyalkyl methacrylates, epoxyalkyl acrylates, epoxyalkyl methacrylates, acrylonitrile, methacrylonitrile, acrylamides, methacrylamides, acrylic acid and mixtures thereof, optionally with an ethylenically unsaturated comonomer.

5. 5. The method of claim 4, wherein the acrylic monomer composition comprises at least 50% by weight of an acrylic monomer and less than 50% by weight of an ethylenically unsaturated comonomer.

6. 6. The method according to claim 1, wherein the water content of the acrylic polymer emulsion is between 25% and 75% by weight.

7. The method of any one of claims 1 to 6, wherein the aqueous coating composition comprises a film-forming agent selected from the group consisting of glycol ethers or glycol esters or combinations thereof.

8. The method according to any one of claims 1 to 7, wherein the aqueous coating composition comprises up to 50% by weight of an additional polymer selected from the group of polyvinyl acetate, polyvinyl alcohol and polyurethane.

9. The method according to any one of claims 1 to 8, wherein the aqueous coating composition comprises a dispersant, a thickener, a filler, an antifoaming agent, a neutralizing agent, a biocide, a matting agent and / or a pigment.

10. A coated building board comprising a color imaging layer of the cured coating composition of any one of claims 1 to 9 on at least a portion of a surface of the building board.

11. 1. A coated building board comprising a color imaging layer on at least a portion of a surface thereof, the color imaging layer comprising 30% to 95% by weight of a layer of an acrylic polymer and 0.5% to 50% by weight of a layer of a molecular sieve, the molecular sieve being a microporous molecular sieve, and at least 90% of the pores of the molecular sieve having a pore size between 0.1 nm and 2 nm.

12. 12. The coated building board of claim 11, wherein the weight ratio of molecular sieve to acrylic polymer in the color imaging layer is from 1:1 to 1:

20.

13. 13. The coated building board of claim 11 or 12, wherein the molecular sieve is a zeolite.

14. A coated building board according to claim 11 or 12, wherein the molecular sieve is a 3 Å, 4 Å, 5 Å zeolite or a mixture thereof.

15. The coated building board according to any one of claims 10 to 14, wherein the building board is a cement plate, a gypsum plate, a ceramic plate, a metal plate, a wood plate or a polymer resin plate.

16. Use of a building board according to any one of claims 10 to 15 as a base material for ink-jet printing with water-based inks.

Images