JP2000086973A - Aqueous curing type sealer and in-line coating of ceramic substrate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an aqueous curing type sealer excellent in efflorescene and blocking resistances. SOLUTION: This aqueous curing type sealer is obtained by compounding the following components: (A) an aqueous resin which is at least one kind of aqueous resin selected from vinylic resins, polyester-based resins, polyurethane- based resins, epoxy-based resins and modified resins thereof and converted into the aqueous resin with carboxyl groups and/or carbonyl groups with (B) a blocked polyisocyanate compound.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a novel aqueous curable sealer and a method for coating the same.

[0002]

2. Description of the Related Art In recent years, as an outer wall material of a building, a material in which an aqueous sealer is coated on the surface of an inorganic porous base material mainly composed of an inorganic material such as cement, calcium silicate or gypsum has been used. I have. The aqueous sealer is coated to have performances such as anti-mold resistance, anti-freezing damage, weather resistance, and efflorescence resistance.

Hitherto, aqueous humic acid solutions and thermoplastic acrylic resin emulsions have been used as aqueous sealers. However, the humic acid aqueous solution has a drawback of poor adhesion to the top coat, and the thermoplastic acrylic resin emulsion has poor blocking resistance, so that the base materials adhere to each other and handling becomes difficult. was there.

[0004] As an aqueous primer, a modified polyolefin containing an acid or a hydroxyl group, an acrylic resin obtained by subjecting an acrylic monomer to a radical polymerization reaction in water in the presence of a surfactant, and an aqueous primer containing a blocked isocyanate compound A base coating for a porous inorganic plate comprising a resin composition (see JP-A-8-67726), a silyl group-modified polyvinyl alcohol, an aqueous emulsion of a synthetic polymer and a polyisocyanate compound (see JP-A-5-67726).
No. 25432). However, when such an aqueous composition is applied to a continuous line coating step having an autoclave curing step, when the aqueous composition is applied before the autoclave curing, the coated article has poor blocking resistance, Further, when the aqueous composition is applied after curing in an autoclave, there is a problem that the coated article is inferior in water resistance and efflorescence resistance.

[0005]

DISCLOSURE OF THE INVENTION The present invention provides a one-pack composition which can satisfy the coating properties such as water resistance, blocking resistance, and efflorescence resistance required for an aqueous sealer and is excellent in storage stability. An object of the present invention is to provide an aqueous curable sealer that can be handled by a mold and a method of coating the same.

[0006]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to solve the above-mentioned problems, and as a result, as a water-based curing type sealer, a specific water-based resin is mixed with a block polyisocyanate compound. Have found that the conventional problems can be solved, and have completed the present invention.

That is, the present invention relates to: 1. The following components, (A) at least one aqueous resin selected from vinyl resins, polyester resins, polyurethane resins, epoxy resins and modified resins thereof. And an aqueous resin in which the aqueous resin is made aqueous with a carboxyl group and / or a carbonyl group, (B)
An aqueous curable sealer characterized by being blended with a block polyisocyanate compound, 2. an aqueous resin, a carbonyl group-containing radically polymerizable unsaturated vinyl monomer and / or as an aqueous monomer component constituting a polymer. The above-mentioned aqueous resin, which is a vinyl resin containing a carboxyl group-containing radically polymerizable vinyl monomer as an essential monomer component, 3, an inline sealer is applied to the surface of the inorganic porous substrate, and after drying, In the step including autoclave curing, the in-line sealer may be used in the form of (A) at least one aqueous resin selected from vinyl-based resins, polyester-based resins, polyurethane-based resins, epoxy-based resins, and modified resins thereof; Ceramic industry characterized by compounding isocyanate compound Related to the in-line coating method of the base material.

[0008] The aqueous curable sealer of the present invention will be described below.

Aqueous resin (A) used in the sealer of the present invention
Is at least one aqueous resin selected from a vinyl resin, a polyester resin, a polyurethane resin, an epoxy resin, and a modified resin thereof, and the aqueous resin is converted to an aqueous resin by a carboxyl group and / or a carbonyl group. Water based resin. As the above-mentioned resin, a conventionally known resin can be appropriately selected and used.
Typical examples of the resin include the following.

(1) Vinyl resin: The vinyl resin is, for example, 0 to 60% by weight, preferably 5 to 45% by weight, of a carbonyl group-containing radically polymerizable vinyl monomer (a).
% By weight, 0 to 20% by weight, preferably 5 to 15% by weight, of a carboxyl group-containing radically polymerizable vinyl monomer (b) and other radically polymerizable unsaturated monomer (c) 2
0 to 94% by weight, preferably 40 to 90% by weight, and the monomer content of (a) + (b) is 6 to 8%.
0% by weight, preferably 10-60% by weight of the radical copolymer. If the mixing ratio of the monomer (a) exceeds the above range, there is a disadvantage that the coating performance such as water resistance is deteriorated. When the blending ratio of the monomer (b) is less than 2% by weight, for example, the permeability to the base material is reduced, and the function cannot be sufficiently exhibited, or the blocking resistance (inorganic porous building base material) However, when the amount exceeds 20% by weight, the water resistance and efflorescence resistance of the coating film are deteriorated.

When the total amount of the above-mentioned monomers (a) and (b) is less than 6% by weight, the permeability to the substrate is inferior, so that the performance such as blocking resistance is deteriorated. Has a disadvantage that the performance such as water resistance is deteriorated.

Carbonyl group-containing unsaturated monomer (a)
Is a monomer having at least one keto group or aldehyde group and one radically polymerizable double bond in one molecule, that is, a polymerizable monoolefinically unsaturated aldehyde compound and a keto compound. Representative specific examples include, for example, diacetone (meth) acrylamide, acrolein, formylstyrene, (meth) acrylamide pivalinaldehyde, diacetone (meth) acrylate, acetonyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate Acetyl acetate, vinyl alkyl ketone and the like can be mentioned. Of these, diacetone (meth) acrylamide is preferred.

Carboxyl group-containing unsaturated monomer (b)
Is an unsaturated compound containing at least one carboxyl group (including carboxyl anhydride group) and one radically polymerizable unsaturated group in one molecule. Representative specific examples include (meth) acrylic acid, maleic anhydride, fumaric acid, itaconic acid, and the like.

The other radically polymerizable unsaturated monomer (c) is a radically polymerizable unsaturated monomer other than those described above, and which does not substantially adversely affect (react, etc.) with the above-mentioned carbonyl group or carboxyl group. Compound. Representative examples include, for example, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, tertbutyl (meth) acrylate, -Ethylhexyl (meth) acrylate, cyclohexyl (meth) acrylate, n
-(Meth) acryls such as octyl (meth) acrylate, lauryl (meth) acrylate, dodecyl (meth) acrylate, stearyl (meth) acrylate, 2-ethylhexylcarbitol (meth) acrylate, and isobornyl (meth) acrylate Alkyl or cycloalkyl ester monomers of acids; acrylic or methacrylic acid such as 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, hydroxybutyl (meth) acrylate Monoester of polyether polyol such as C2-C8 hydroxyalkyl ester, polyethylene glycol, polypropylene glycol, polybutylene glycol and unsaturated carboxylic acid such as (meth) acrylic acid Hydroxyl-containing radically polymerizable monomers such as hydroxyalkyl vinyl ethers such as ter and hydroxyethyl vinyl ether; methoxybutyl (meth) acrylate, methoxyethyl (meth) acrylate, ethoxybutyl (meth) acrylate, trimethylolpropane tripropoxy (meth) acrylate Such as alkoxyalkyl ester monomers of (meth) acrylic acid; aromatic vinyl monomers such as styrene, α-methylstyrene, and vinyl toluene; esters of aromatic alcohols such as benzyl (meth) acrylate and (meth) acrylic acid; Unsaturated monomer: vinyltriethoxysilane, vinyltrimethoxysilane, vinyltris (methoxyethoxy) silane, γ- (meth) acryloyloxypropyltrimethoxysilane, 2- Styryl ethyltrimethoxysilane, vinyltrichlorosilane, .gamma.
Hydroxysilane and / or hydrolyzable silane group-containing vinyl monomers such as (meth) acryloyloxypropyltriacetoxysilane, γ- (meth) acryloyloxypropyltrihydroxysilane, and γ- (meth) acryloyloxypropylmethylhydroxysilane A perfluoroalkyl (meth) acrylate such as perfluorobutylethyl (meth) acrylate, perfluoroisononylethyl (meth) acrylate, and perfluorooctylethyl (meth) acrylate;

In the other radically polymerizable unsaturated monomer (c) described above, by using the hydroxyl group-containing radically polymerizable monomer (d), the aqueous resin (A) is cured by the blocked polyisocyanate compound (B) and crosslinked. It is preferable to use this as it forms a coating film. The hydroxyl group forms a crosslinked coating film with the blocked polyisocyanate compound and exhibits excellent properties such as blocking resistance, efflorescence resistance, and water resistance. The content of the hydroxyl group is about 0
~ 300mgKOH / g, preferably about 10 ~ 200m
gKOH / g.

The vinyl resin is preferably produced by a solution polymerization method. Specifically, for example, a radical polymerization initiator (for example, an azo-based initiator, a peroxide-based initiator, or the like) is prepared by using the above-described radical-polymerizable monomer in a solvent containing a hydrophilic organic solvent such as an alcohol solvent or an ether solvent. By reacting at a temperature of about 50 to 140 ° C. for about 4 to 10 hours in the presence of

The vinyl resin has a number average molecular weight of about 100.
The range of 0-100,000, especially 2000-20,000 is preferable. When the number average molecular weight is less than about 1000, water resistance and the like decrease, while when the number average molecular weight exceeds 100000, the permeability to the base material is deteriorated, and the blocking resistance is deteriorated.

(2) Polyester resin: Examples of the polyester resin include polybasic acids (for example, (anhydrous)).
Phthalic acid, isophthalic acid, terephthalic acid, (anhydrous) maleic acid, (anhydrous) pyromellitic acid, (anhydrous) trimellitic acid, (anhydrous) succinic acid, sebacic acid, azelaic acid,
Compounds having 2 to 4 carboxyl groups or carboxylic acid methyl ester groups in one molecule such as dodecanedicarboxylic acid, dimethyl isophthalate, dimethyl terephthalate, etc.)
And polyhydric alcohols (eg, ethylene glycol, propylene glycol, neopentyl glycol, 1,6-
Hexanediol, diethylene glycol, triethylene glycol, trimethylolpropane, pentaerythritol, glycerin, tricyclodecanedimethanol, dimethylolpropionic acid, and other alcohols having 2 to 6 hydroxyl groups in one molecule) are required for aqueous conversion. It is obtained by performing an esterification reaction or a transesterification reaction such that a sufficient carboxyl group remains. In addition to the above, monobasic acids (for example, fatty acids such as castor oil fatty acid, soybean oil fatty acid, tall oil fatty acid, and linseed oil fatty acid, and benzoic acid), and fats and oils can be used as necessary.

The carboxyl group of the polyester resin has a resin acid value of about 20 to 200 mgKOH / g, preferably about 30 to 150 mgKOH / g. When the acid value is below the lower limit, the permeability to the substrate is poor, and the performance such as blocking resistance and efflorescence resistance deteriorates. On the other hand, when the acid value exceeds the upper limit, the performance such as the water resistance of the coating film deteriorates. There are drawbacks.

The polyester resin preferably has a number average molecular weight of about 500 to 20,000, more preferably 700 to 10,000. When the number average molecular weight is less than about 500, the water resistance and the like decrease, while when the number average molecular weight exceeds 20,000, the permeability to the base material is deteriorated, and the blocking resistance is deteriorated.

(3) Polyurethane resin: Examples of the polyurethane resin include dimethylolpropionic acid and, if necessary, a polyol (alkoxypolyalkylene glycol, for example, ethylene glycol, propylene glycol, methoxypolymethylene ether). Terglyco-
Methoxypolyethylene etherglycol, ethoxypolyethyleneetherglycol, ethoxypolybutyleneetherglycol, etc.) and a polyisocyanate compound. Examples of the polyisocyanate compound include tetramethylene diisocyanate
Aliphatic diisocyanates such as hexamethylene diisocyanate, trimethyl hexamethylene diisocyanate, and isophorone diisocyanate; 4.4'-methylene bis (cyclohexyl isocyanate), isophorone diisocyanate Alicyclic diisocyanates such as neat; xylylene diisocyanate; tolylene diisocyanate;
Aromatic diisocyanates such as diphenylmethane diisocyanate and polyphenylmethane diisocyanate (hereinafter referred to as polymeric MDI); and isocyanurates thereof
And similar compounds such as pentamer and burette, and these can be used alone or in combination of two or more.

(4) Epoxy resin: As the epoxy resin, for example, a conventionally known epoxy resin having at least one epoxy group in one molecule [for example, a radical polymerizable monomer containing an epoxy group (for example, ,
(3,4-epoxycyclohexylmethyl (meth) acrylate), glycidyl (meth) acrylate, and the like, a single radical polymer, and the monomer and another radical polymerizable monomer (for example, having 1 to 2 carbon atoms of (meth) acrylic acid)
4, an alkyl or cycloalkyl ester, styrene, etc.), Eporide GT300 (trade name, manufactured by Daicel Chemical Industries, Ltd., trifunctional alicyclic epoxy resin), Eporide GT400 (Daicel Chemical Industries, Ltd.)
Company name, trade name, 4-functional alicyclic epoxy resin), EHPE
(Trade name, trifunctional alicyclic epoxy resin, manufactured by Daicel Chemical Industries, Ltd.), bisphenol-type epoxy resin, novolak-type epoxy resin, ε-caprolactam-modified bisphenol-type epoxy resin, polyvinylcyclohexene diepoxide, etc.] Examples thereof include those obtained by denaturation with an acid. Examples of the polycarboxylic acid include a polycarboxylic acid resin (eg, an acrylic resin and a polyester resin) and a polycarboxylic acid compound (eg, adipic acid, sebacic acid, phthalic acid, etc.).

The carboxyl group of the epoxy resin has a resin acid value in the range of about 20-200 mgKOH / g, preferably about 30-150 mgKOH / g. When the acid value is below the lower limit, the permeability to the substrate is poor, and the performance such as blocking resistance and efflorescence resistance deteriorates. On the other hand, when the acid value exceeds the upper limit, the performance such as the water resistance of the coating film deteriorates. There are drawbacks.

The epoxy resin has a number average molecular weight of about 50.
The range of 0 to 20,000, particularly 700 to 10,000 is preferred. When the number average molecular weight is less than about 500, the water resistance and the like decrease, while when the number average molecular weight exceeds 20,000, the permeability to the base material is deteriorated, and the blocking resistance is deteriorated.

The above-mentioned aqueous resin may contain a hydroxyl group. The hydroxyl group forms a crosslinked coating film with the blocked polyisocyanate compound and exhibits excellent properties such as blocking resistance, efflorescence resistance, and water resistance. The content of the hydroxyl group is about 20 to 200 mgKOH / g, preferably about 30 mgKOH / g.
１５０150 mgKOH / g.

The blocked polyisocyanate compound (B) used in the sealer of the present invention is a conventionally known aqueous or polyisocyanate compound containing two or more, preferably 2 to 4 isocyanate groups in one molecule, which are blocked with a blocking agent. An organic solvent-based blocked polyisocyanate compound can be used. As the aqueous blocked polyisocyanate compound, the compound itself has a water-solubility or water-dispersibility, or a surfactant can be added or a hydrophilic protective colloid can be formed even if the compound itself has no water-solubility or water-dispersibility. A water-based material can be used. As the water-soluble or water-dispersible substance, for example, a blocking agent may be used for a reaction product containing a free isocyanate group at a terminal obtained by reacting an alkoxypolyalkylene glycol with a polyisocyanate compound. Are blended.

Examples of the alkoxypolyalkylene glycol include methoxypolymethylene ether glycol, methoxypolyethylene ether glycol, ethoxypolyethylene ether glycol, ethoxypolybutylene ether glycol and the like. Having a molecular weight of 1
Those having a range of from 00 to 4,000, preferably from 400 to 2,000 can be used.

The organic solvent-based blocked polyisocyanate compound is a compound which is itself dissolved or dispersed in a hydrophilic or hydrophobic organic solvent. Examples of the hydrophilic organic solvent include alcohols such as methanol, ethanol, n-propanol and isopropanol, and ethers such as cellosolve, methyl cellosolve, butyl cellosolve and carbitol acetate. Examples of the hydrophobic organic solvent include hydrocarbons such as toluene and xylene, ketones such as methyl isobutyl ketone, 2-hexanone, isophorone and cyclohexanone, methyl acetate, ethyl acetate, and propyl acetate.
Examples thereof include esters such as butyl acetate and alcohols such as butanol and hexanol.

The blending ratio of the blocked polyisocyanate compound (B) is such that the blocked polyisocyanate compound (B) is about 1 to 100 parts by weight, preferably about 100 parts by weight, based on 100 parts by weight of the aqueous resin (solid content). 5-80
It is in the range of parts by weight. If the amount of the block polyisocyanate compound (B) is less than about 1 part by weight, the blocking resistance, efflorescence resistance, water resistance, adhesion, etc. decrease, while if it exceeds about 100 parts by weight, the blocking resistance decreases. Not preferred. When the aqueous resin contains a hydroxyl group, the equivalent ratio to NCO / OH is about 0.1 to
A range of 2 equivalents, preferably about 0.5 to 1.5 equivalents, is desirable. When the equivalent ratio of NCO / OH is less than about 0.1 equivalent, blocking resistance, efflorescence resistance, water resistance, adhesion and the like are reduced. On the other hand, when the equivalent ratio of NCO / OH is more than about 2 equivalent, blocking resistance is reduced, so that it is preferable. Absent.

When the aqueous resin does not have a hydroxyl group, the blocked polyisocyanate compound (B) penetrates the inorganic base material and reacts with the hydroxyl groups present in the inorganic base material to react with the sealer and the base material. And a polymer coating film is formed by a polymerization reaction of the compound (B) itself, so that a coating film having excellent blocking resistance, efflorescence resistance, water resistance, adhesion and the like is formed. You. In addition, when the aqueous resin has a hydroxyl group, it penetrates the inorganic base material and reacts with the hydroxyl group present in the inorganic base material, and also chemically bonds with the aqueous resin at the same time, so that the adhesion to the base material is excellent. Further, since a polymer coating film is formed by crosslinking the aqueous resin, a coating film having excellent blocking resistance, efflorescence resistance, water resistance and the like is formed.

The process for producing a sealer according to the present invention comprises, for example, when the aqueous resin (A) has a carboxyl group which requires neutralization required for aqueous conversion, the aqueous resin (A) and the blocked polyisocyanate compound (B) After adding a neutralizing agent to the mixture, the mixture is made aqueous (the mixture can be made aqueous by adding water to the obtained mixture or by adding the mixture to water. The same meaning applies hereinafter) or After adding and mixing the neutralizing agent of the resin (A), the obtained neutralized resin is blended with the blocked polyisocyanate compound (B) and then made aqueous, or the blocked polyisocyanate compound (B) itself is used. Can be obtained by mixing the blocked polyisocyanate compound (B) with the aqueous solution of the above neutralized resin. When the aqueous resin (A) has a carbonyl group that can be converted to an aqueous solution without neutralization, the mixture of the aqueous resin (A) and the blocked polyisocyanate compound (B) is converted to an aqueous solution, The one in which the polyisocyanate compound (B) itself disperses in water can be obtained by mixing the blocked polyisocyanate compound (B) with the aqueous liquid of the aqueous resin.

Examples of the neutralizing agent include ammonia;
Primary amines such as ethylamine, propylamine, butylamine, benzylamine, monoethanolamine, neopentanolamine, 2-aminopropanol, 3-aminopropanol; diethylamine, diethanolamine, di-n- or di-iso-propanolamine Secondary amines such as dimethylethanolamine, N-methylethanolamine and N-ethylethanolamine; tertiary amines such as dimethylethanolamine, trimethylamine, triethylamine, triisopropylamine, methyldiethanolamine and dimethylaminoethanol; sodium hydroxide, hydroxide And inorganic hydroxides such as potassium. The neutralization equivalent is about 0.4 to carboxyl group.
A range of 1.8 equivalents, preferably about 0.5 to 1.2 equivalents, is desirable.

In addition to the above, an amino resin, a polyhydrazide compound, colloidal silica, a compound containing a hydrolyzable silane group and / or a hydroxysilane group can be added to the sealer of the present invention, if necessary.

The amino resin is capable of forming a crosslinked coating film by the reaction of the amino resin itself using the carboxyl group of the aqueous resin (A) as a catalyst. Examples of the amino resin include a methylolated amino resin obtained by reacting an amino component such as melamine, urea, benzoguanamine, acetoguanamine, steroganamin, spiroguanamine, or dicyandiamide with an aldehyde. Aldehydes include formaldehyde, paraformaldehyde, acetaldehyde, benzaldehyde and the like.
Further, those obtained by etherifying the methylolated amino resin with an appropriate alcohol can also be used. Examples of the alcohol used for the etherification include methyl alcohol,
Examples include ethyl alcohol, n-propyl alcohol, i-propyl alcohol, n-butyl alcohol, i-butyl alcohol, 2-ethylbutanol, 2-ethylhexanol and the like. As the amino resin, in particular, a melamine resin, furthermore, a part or all of the methylol group of the amino resin, for example, methyl alcohol, ethyl alcohol, a low molecular weight alkoxy melamine resin etherified with a lower alcohol such as propyl alcohol to make it water-soluble. It is preferred to use. Specifically, for example, a melamine in which the methylol group is methyletherified on average 3 or more per triazine nucleus or a melamine resin in which a part of the methoxy group is substituted with an alcohol having 2 or more carbon atoms, and Melamine resins having an average degree of condensation of about 2 or less and a mononuclear ratio of about 50% by weight or more are preferred.

As the low molecular weight alkoxymelamine, commercially available products such as Cymel 303 and Cymel 32
5, Cymel 327, Cymel 350, Cymel 370
[All manufactured by Mitsui Chemicals, Inc.], Nikarac MS17, Nikarac MS15 [All manufactured by Sanwa Chemical Co., Ltd.]; 30W [Sumitomo Chemical Co., Ltd.]
Methyl etherified melamine, Cymel 202, Cymel 235, Cymel 238, Cymel 254, Cymel 272, Cymel 1130 (all manufactured by Mitsui Chemicals, Inc.), Niclac MX-485, Niclac MX-48
7 [all manufactured by Sanwa Chemical Co., Ltd.] and mixed ether melamines such as Resin 755 [manufactured by Monsanto].

The mixing ratio of the amino resin (in terms of solid content)
The aqueous resin (A) has a solid content of about 0 to 50 parts by weight based on 100 parts by weight.
Parts by weight, preferably in the range of 1 to 45 parts by weight.

The polyhydrazide compound is a compound which forms a crosslinked structure by reacting with the carbonyl group containing two or more hydrazide groups (—CO—NH—NH 2) in one molecule.

Representative specific examples of polyhydrazide compounds include, for example, dihydrazide such as carbodihydrazide, oxalic acid dihydrazide, malonic acid dihydrazide, succinic acid dihydrazide, glutaric acid dihydrazide, adipic acid dihydrazide, sebacic acid dihydrazide, eicoic acid diacid. C2-40 aliphatic carboxylic acid dihydrazide such as dihydrazide, phthalic acid dihydrazide, terephthalic acid dihydrazide, isophthalic acid dihydrazide, pyromellitic acid dihydrazide, pyromellitic acid trihydrazide, aromatic polyhydrazide such as pyromellitic acid tetrahydrazide,
And maleic dihydrazide, fumaric dihydrazide,
Other polyhydrazides such as monoolefinically unsaturated dihydrazide such as itaconic acid dihydrazide, bissemicarbazide, polyacrylic acid polyhydrazide, and 1,3-bis (hydradi / carboethyl) -5-isopropylhydantoin are exemplified.

The compounding ratio of the polyhydrazide compound is 0 to 2 equivalents to the carbonyl group of the aqueous resin (A).
Preferably it is in the range of 0 to 1 equivalent.

Colloidal silica is a dispersion in water containing SiO ₂ as a basic unit and has a particle diameter of 4 to 100 nm. The colloidal silica has a pH of about 7.
One or more can be used. Specifically, for example, Snowtex 20, Snowtex C, Snowtex N
(These are Nissan Chemical Industries, trade names).

The mixing ratio of the colloidal silica is in the range of 0 to 400 parts by weight, preferably 0 to 100 parts by weight in terms of solids, based on 100 parts by weight of the total solids of the aqueous resin (A). By incorporating such colloidal silica, blocking resistance can be imparted to the film of the sealer.

The compound containing a hydrolyzable silane group and / or a hydroxysilane group contains at least two hydrolyzable silane groups or hydroxysilane groups per molecule, or at least one or more hydrolyzable silane groups and hydroxysilane groups. Is a silane compound. Representative specific examples include, for example, dimethoxydimethylsilane, dimethoxydiethylsilane, dimethoxydiphenylsilane, diethoxydimethylsilane, diethoxydiethylsilane, diethoxydiphenylsilane, dipropoxydimethylsilane,
Dialkoxysilanes such as dipropoxydiethylsilane, dipropoxydipropylsilane, dipropoxydiphenylsilane, dibutoxydimethylsilane, dibutoxydiethylsilane, dibutoxydibutylsilane, dibutoxydiphenylsilane; trimethoxymethylsilane, trimethoxyethyl Silane, trimethoxypropylsilane, trimethoxybutylsilane, trimethoxyphenylsilane, triethoxymethylsilane, triethoxyethylsilane, triethoxybutylsilane, triethoxyphenylsilane, tripropoxymethylsilane, tripropoxypropylsilane, tripropoxyphenyl Trialkoxysilanes such as silane and tributoxyphenylsilane; tetramethoxysilane, tetraethoxysilane, tetrapropoxysilane Tetraalkoxysilanes such as tetrabutoxysilane, dimethoxydiethoxysilane and tetraphenoxysilane; hydroxysilanes such as trimethylsilanol, tripropylsilanol, tributylsilanol, triheptylsilanol and triphenylsilanol; γ-N- (2-amino Aminosilanes such as ethyl) aminopropyltrimethoxysilane, p- (N, N-dimethylamino) phenyltriethoxysilane and 3-aminopropylmethyldiethoxysilane; vinyltriethoxysilane, vinyltrimethoxysilane, vinyltris (methoxyethoxy) ) Vinylsilanes such as silane, γ-methacryloyloxypropyltrimethoxysilane and 2-styrylethyltrimethoxysilane;
Epoxysilanes such as (3,4-epoxycyclohexyl) ethyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane; γ-mercaptopropyltrimethoxysilane, γ-mercapto Propylmethyldimethoxysilane, γ-chloropropyltrimethoxysilane, γ
-Other silanes such as chloropropylmethyldimethoxysilane, methyltrichlorosilane, dimethyldichlorosilane, and trimethylchlorosilane; condensates of these silane compounds; and radical (co) polymers of vinylsilanes.

The compounding ratio of the compound containing a hydrolyzable silane group and / or a hydroxysilane group is determined based on the aqueous resin (A)
The solid content is about 0 to 100 parts by weight.
It is in the range of 20 parts by weight, preferably about 0 to 15 parts by weight.

Further, in addition to the above, a coloring pigment, extender pigment, filler, curing catalyst, fluidity regulator, defoamer, organic solvent, etc. can be further incorporated into the aqueous curable sealer, if necessary. .

The aqueous curable sealer of the present invention is, for example,
Inorganic porous substrates mainly composed of inorganic materials such as cement, calcium silicate, and gypsum (for example, building materials such as calcium silicate board, asbestos cement board, wood chip cement board, pulp cement board, lightweight cellular concrete board, etc. Structural materials, civil engineering materials, or industrial materials).

The solid content of the aqueous curable sealer is used at a concentration of 1 to 40% by weight, preferably 3 to 20% by weight.
When the solid content is less than 1% by weight, the number of coatings increases to secure the coating film thickness, so that the coating workability deteriorates. On the other hand, when the solids content exceeds 40% by weight, the permeability to the substrate is poor, so that the blocking resistance is poor. Become.

The coating amount (in terms of solid content) of the aqueous curable sealer is 0.1 to 30 g / m ² , preferably 0.5 to ² g / m ² .
The range is 0 g / m ² . When the coating amount is less than 0.1 g / m ^{2, the} efflorescence resistance is reduced, while 30 g / m 2
^If it exceeds ² , the blocking resistance and the like are undesirably reduced.

The coating method of the aqueous curable sealer is not particularly limited, and a conventionally known coating method, for example, a roller,
It can be performed by a method such as brushing, spraying, dipping, or a flow coater (such as a curtain flow coater).

The drying of the aqueous curable sealer may be performed, for example, when the base material is heated by primary curing or the like.
It is preferable to perform drying by remaining heat (about 60 ° C.) of the base material by the next curing. When the substrate is not preheated, it varies depending on the type of the substrate, but usually about 20 to 200.
It is preferable to perform drying at a temperature of about 3 seconds to 60 minutes. In the drying, in particular, drying by the residual heat of the base material is performed in such a manner that the sealer is applied in a state where the base material is warm, so that the permeability to the base material is excellent, and thus the cross-linking reaches the inside of the base material. In addition, there is an advantage that performance such as blocking resistance is excellent.

The autoclave curing can be carried out, without any particular limitation, under the conditions employed for ceramic substrates. Usually, the reaction is carried out at about 160 to 170 ° C., about 8 to 9 kgf / cm ² for about 4 to 8 hours in the presence of steam.

[0051]

Next, the present invention will be described in detail with reference to examples.

Production Example of Aqueous Curable Sealer a 300 equipped with a thermometer, stirrer, cooler and dropping funnel
100 g of propylene glycol monomethyl ether was placed in a four-neck flask of cc, and the temperature was raised to 80 to 90 ° C., and 10 g of methyl methacrylate, 35 g of N-butyl acrylate, 10 g of 2-hydroxyethyl acrylate, 5 g of styrene, 5 g of diacetone A mixture of 30 g of acrylamide, 10 g of acrylic acid and 1 g of azobisisobutyronitrile was added dropwise over 3 hours. After aging at the same temperature for 1 hour, azobisbutyronitrile 1 was added.
g was added as an additional catalyst, and the mixture was aged for 2 hours to obtain an acrylic solvent-based aqueous organic solvent solution having a resin solid content of 50% by weight, a resin acid value of 80 KOH mg / g, and a number average molecular weight of the resin of about 6,000.

Then, 0.9 equivalent of a neutralizing agent of triethylamine was added to the solution, and the mixture was stirred and mixed.
Deionized water was gradually added dropwise and stirred until the weight of the aqueous resin solution reached 10% by weight to produce an aqueous resin liquid. The aqueous resin liquid was pale yellow and transparent.

An aqueous liquid of a block polyisocyanate compound (BL5140, manufactured by Sumitomo Bayer Urethane Co., trade name, resin solid content 3
An aqueous curable sealer a was manufactured by blending 60 g of 9.5% (hereinafter the same meaning).

Production Examples of Aqueous-Curable Sealers b to g Resins and aqueous-curable sealers were produced in the same manner as in the method for producing the resin of the aqueous-curable sealer a at the monomer mixing ratio shown in Table 1.

[0056]

[Table 1]

Examples 1 to 5 Table 2 shows the results of the following tests performed using the aqueous curable sealer shown in Table 1.

[0058]

[Table 2]

Comparative Examples 1-2 The results of the following tests performed using the aqueous curable sealer of Table 1 are shown in Table 2.

In Table 2, the test method was performed as follows.

Efflorescence resistance: The aqueous curable sealer obtained above was processed into a cement paste (cement / petroleum / water = 100/4/35 weight ratio), processed into a plate, and left for 30 minutes. Thing) 50 coating amount on the surface
g / m ² , spray-dried and left to dry, then autoclaved (160-170 ° C., about 8-9 kg)
f / cm ² , under a steam atmosphere for about 6 hours), and then the sealer coating film was evaluated. The evaluation was performed according to the following criteria. ◎ indicates no whitening at all, は indicates slight whitening but no practical problem, Δ indicates poor whitening, and × indicates significant whitening.

Blocking resistance: An aqueous curable sealer was spray-coated on ^two slate plates so as to have a coating amount of 50 g / m ^2, and dried at 100 ° C. for 5 minutes. Was pressed at a load of 400 g / cm ² , heated at 170 ° C. for 1 hour, cooled to room temperature, and examined for ease of peeling between the two slate plates. The evaluation was performed according to the following criteria. ◎: good without any adhesion, ○: slightly adhered but peelable with light force and no problem in practical use, △: peelable without applying strong force, ×: peelable It is difficult.

Water resistance: The water-curable sealer obtained above was spray-coated on the surface of the slate plate so as to have a coating amount of 50 g / m ² , dried by standing and then cured in an autoclave (160 ° C. to 170 ° C., approx. 8-9 kgf / cm ² , about 6
(Under a steam atmosphere for an hour), and then a top coat paint (Ales Aqua Gloss, manufactured by Kansai Paint Co., Ltd., trade name, water-based emulsion paint) is spray-coated so that the dry film thickness becomes about 30 μm, and 100 ° C. For 20 minutes to prepare a coated substrate for testing. Put this in water 2
After immersion at 0 ° C. for 30 days, the top coat was observed for cracks, peeling, blistering and other coating abnormalities.

Alkali resistance: A test coated substrate formed in the same manner as the above-mentioned water resistance was used for this test. After this substrate was immersed in a saturated aqueous solution of calcium hydroxide at 20 ° C. for 30 days, the presence or absence of a coating abnormality such as cracking, peeling, or blistering of the overcoat was observed.

[0065]

The aqueous curable sealer of the present invention exerts excellent effects on the coating properties such as blocking resistance and water resistance.

In the aqueous curable sealer of the present invention, the carboxyl group and the carbonyl group in the aqueous resin have excellent blocking resistance due to excellent permeability to the base material, and have high hardness and toughness due to the blocked polyisocyanate compound. It is considered that since the film is formed, a remarkable effect such as excellent film performance such as water resistance and blocking resistance is exhibited.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Masaaki Shinohara 4-171-1, Higashi-Hachiman, Hiratsuka-shi, Kanagawa Prefecture Inside Kansai Paint Co., Ltd. (72) Inventor Hiroe Yamanaka 4-171-1, Higashi-Hachiman, Hiratsuka-shi, Kanagawa F-term (reference) in Nishi Paint Co., Ltd. HA04 4J034 CA04 CA22 CB03 CB04 CB07 CB08 CC03 DA01 DA05 DB04 DB07 DF16 DF20 DF21 DF22 DF24 DF29 DG03 DG04 DG05 DG06 DG09 DK03 DK05 DK06 DK09 DP03 DP13 DP18 EA11 EA12 EA13 HC01 HC06 HC12 HC13 HC01 HC71 HC73 HD00 QB11 QC05 RA07 4J038 CE051 CG031 CG071 CG081 CG141 C H031 CH041 CH071 CH121 CH131 CH141 CJ031 CL001 DB001 DD051 DG001 GA06 JB18 PB12 PC03 PC04

Claims (3)

[Claims] 1. An aqueous resin selected from the following components, (A) a vinyl resin, a polyester resin, a polyurethane resin, an epoxy resin, and a modified resin thereof, wherein the aqueous resin is An aqueous curable sealer comprising an aqueous resin which is made aqueous with a carboxyl group and / or a carbonyl group, and (B) a blocked polyisocyanate compound. 2. The aqueous resin contains a carbonyl group-containing radically polymerizable unsaturated vinyl-based monomer and / or a carboxyl group-containing radically polymerizable vinyl-based monomer as an essential monomer component as an aqueous monomer component constituting a polymer. The aqueous resin according to claim 1, wherein the aqueous resin is a vinyl resin. 3. An inline sealer is applied to the surface of an inorganic porous substrate, dried, and then, in a step including autoclave curing, the inline sealer comprises (A) an acrylic resin, a polyester resin, a polyurethane resin,
An in-line coating method for a ceramic substrate, comprising blending at least one aqueous resin selected from an epoxy resin and a modified resin thereof, and (B) a blocked polyisocyanate compound.