JP3335432B2 - Manufacturing method of base material for building - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a base material for a building used for mortar coating of an outer wall of a building, spraying of ricin, stucco or the like.

[0002]

2. Description of the Related Art Conventionally, a method of constructing a mortar painted wall centering on a wooden house is to fix a wood lath or the like with nails, attach a waterproof paper such as tar felt, and fix a metallic lath net thereon. After that, mortar coating or spraying material such as lysine, stucco, etc. was applied, but this method required time for preparation for construction and had problems in the construction period. In order to solve these problems, a mixture of a thermoplastic aqueous emulsion such as methacrylbutyl rubber, styrene-butadiene rubber, chloroprene rubber and an inorganic aggregate is applied to a board surface used as a base material, and carbonic acid is further applied thereon. An impregnated layer with a latex sealer is provided on a surface layer of a base material such as a mortar wall construction substrate coated with a so-called cement paste, which is a mixture of calcium, silica sand and latex cement (Japanese Patent Application Laid-Open No. 53-12125). A base material (Japanese Patent Publication No. 55-12940) having an uneven coating layer of latex cement thereon, an acrylic emulsion, an ethylene-vinyl acetate copolymer emulsion, a polypropylene emulsion, and a synthetic rubber on a plate-like base material such as plywood. Apply a waterproof layer with latex, etc., and over it an inorganic binder such as cement Method of providing a layer of a mixture of foamed synthetic resin grains (JP 55-30049), with respect to 100 parts by weight of an aqueous emulsion, a thermosetting resin 2
A method in which a mixture obtained by mixing 40 parts by weight (in terms of solid content) is applied, dried, and then a cement paste containing Portland cement as a main component is applied and solidified (JP-A-55-158184). It has been proposed and partially put into practical use.

[0003]

However, as described above, a thermoplastic aqueous emulsion such as a synthetic rubber latex, an acrylic emulsion or an ethylene-vinyl acetate copolymer emulsion is simply added to an inorganic bone such as calcium carbonate or silica sand cement. When a mixture of materials is applied and a cement paste is applied, it lacks adhesion, water resistance, warm water resistance, boiling resistance and impact resistance as a base material for building, and furthermore, especially wood such as plywood When used for a system board, there is a problem that the hardening inhibition and sealing properties of cement are lacking, which is said to be caused by the sap (tarnish) contained in the wood board. Further, when the aqueous emulsion is used alone as a sealer for a wood-based board, a fibrous board or an inorganic-based board, the inhibition of cement hardening is avoided, but water resistance, warm water resistance, boiling resistance, etc. are problematic. There is. It has been partially put into practical use as a method to improve these disadvantages,
There is a method of using a mixture of a thermosetting resin such as an aqueous emulsion and an epoxy resin, a phenol resin, an amino resin, and a polyester resin as a sealer, but when these thermosetting resins are blended, depending on the type of the thermosetting resin, A combination of a curing agent or a curing accelerator is required, and a mixture of these resins in an aqueous emulsion must be used up within a few hours. There are problems such as the dispersion of the adhesive properties due to the weighing error and the lack of economy.

[0004]

The present inventors have conducted intensive studies to solve the above problems, and as a result, have found that aromatic vinyl monomers, unsaturated carboxylic acid ester monomers, acrylic monomers having an amide group, A so-called core-shell in which an aromatic vinyl monomer, an unsaturated carboxylic acid ester monomer, an acrylic monomer having a hydroxyl group, an acrylic monomer having an amide group, and a carboxyl group-containing monomer are copolymerized on the outside of an emulsion particle obtained by copolymerizing an epoxy resin. The epoxy-modified acrylic emulsion having a structure has excellent storage stability, and has a storage stability even when used in combination with a curing agent for an epoxy resin represented by an amine or a polyamide, that is, a one-pack type. When used as a sealer for cement boards or inorganic boards, Adhesion to the bets material, water resistance, found that hot water is building base material having excellent boiling resistance and impact resistance, and have completed the present invention.

That is, the present invention provides the following 1. ~ 5. It is as follows. 1. The core layer is a copolymer of an aromatic vinyl monomer, an unsaturated carboxylic acid ester monomer, an acrylic monomer having an amide group and an epoxy resin, and the shell layer has an aromatic vinyl monomer, an unsaturated carboxylic acid ester monomer, and a hydroxyl group. It is obtained by previously blending a curing agent (b) for an epoxy resin with an epoxy-modified acrylic emulsion (a) having a core-shell structure, which is a copolymer of an acrylic monomer, an acrylic monomer having an amide group, and a monomer having a carboxyl group. A one-part curable aqueous emulsion is applied as a sealer to the surface of a wooden board, a fibrous board or an inorganic board as a sealer and dried, and then a cement paste material is applied thereon and solidified, thereby providing a base material for building. Manufacturing method. 2. The epoxy-modified acrylic emulsion is characterized in that 5 to 50 parts by weight of an epoxy resin is copolymerized in 100 parts by weight of the solid content of the emulsion. The method for producing a base material for building described in the above. 3. The glass transition temperature (Tg) of the epoxy-modified acrylic emulsion is in the range of -20 to + 30 ° C. The method for producing a base material for building described in the above. 4. The glass transition temperature (Tg) of the core layer of the epoxy-modified acrylic emulsion is in the range of −10 to + 60 ° C., and the glass transition temperature (Tg) of the shell layer is in the range of −40 to + 10 ° C. The method for producing a base material for building described in the above. 5. The one-part curing type aqueous emulsion is characterized in that a curing agent for an epoxy resin is blended in an amount of 5 to 25 parts by weight as a solid content with respect to 100 parts by weight of a solid content of the epoxy-modified acrylic emulsion. The method for producing a base material for building described in the above.

The epoxy-modified acrylic emulsion having a core-shell structure of the present invention (hereinafter abbreviated as EPAE) (a) is prepared by first preparing a mixed monomer obtained by dissolving an epoxy resin in various monomers used for the core layer. It is gradually added to distilled water containing a surfactant with stirring at room temperature to produce a so-called pre-emulsified monomer. Next, distilled water and a surfactant were charged into a flask equipped with a stirrer and a condenser, the atmosphere was replaced with nitrogen, the temperature was raised to 70 ° C., the polymerization initiator was administered, the pre-emulsified monomer was added dropwise over a certain period of time, and the addition was completed. Thereafter, at the same temperature, the remaining monomers are reacted to form emulsion particles serving as the core of the present invention. Subsequently, various monomers used for the shell layer were converted into pre-emulsified monomers in the same manner as in the case of the core layer, and then dropped into the flask over a certain period of time, and the remaining monomers were allowed to react in the same manner as described above. EPAE having a so-called core-shell structure coated with core particles is obtained. After completion of the reaction, the mixture is cooled to 40 ° C. or less, and the pH is adjusted to 6 to 9 with aqueous ammonia.
The EPAE used in the present invention can be obtained by adjusting the pH to 100 and filtering through a 100 mesh wire mesh.

Styrene, α-methylstyrene and the like are unsaturated vinyl carboxylate esters.
Monomers include methyl methacrylate and ethyl meth
Acrylate, isobutyl methacrylate, tert
Butyl methacrylate, ethyl acrylate, isobut
Butyl acrylate, n-butyl acrylate,
Xyl acrylate, 2-ethylhexyl metaacrylate
And C 4-12 carbon atoms such as lauryl methacrylate.
Acrylic acid or methacrylic acid
Steal. Among them, the combined use of styrene and n-butyl acrylate is preferred from the viewpoint of economy and ease of emulsion polymerization. Examples of the acrylic monomer having a hydroxyl group include hydroxyethyl acrylate, hydroxyethyl methacrylate, and hydroxypropyl acrylate.
Among them, hydroxyethyl methacrylate is preferred from the viewpoint of stability after blending the curing agent for epoxy resin. Examples of the acryl monomer having an amide group include acrylamide, methacrylamide, maleimide, N-methylolacrylamide, and N-methylol methacrylamide. Among them, methacrylamide or N-methylol methacrylamide is preferable from the viewpoint of water resistance, warm water resistance and boiling resistance. Examples of the monomer having a carboxyl group include acrylic acid, methacrylic acid, itaconic acid, maleic acid, fumaric acid and the like.Among them, acrylic acid or methacrylic acid is preferable from the viewpoint of stability during emulsion polymerization, mechanical and chemical stability. preferable.

Examples of the epoxy resin include bis-epi type composed of bisphenol A and epichlorohydrin, cyclic fatty acid type composed of a cyclic fatty acid unsaturated compound and peracetic acid, novolak type composed of a phenol resin and epichlorohydrin, and tetraepoxy composed of glyoxal, phenol and epichlorohydrin. Type, polybutadiene type composed of polybutadiene and peracetic acid, halogenated type composed of halogenated bisphenol A and epichlorohydrin, side chain type composed of bisphenol A and epichlorohydrin and propylene oxide, other polyalkylene ether type, ester type, methyl substituted type, etc. can give. Among these, bisphenol A-
An epichlorohydrin type resin is suitable, and for example, an epoxy resin having an epoxy equivalent of 180 to 270 and a viscosity of 5 to 150 poise is preferable.

The copolymerization ratio of the epoxy resin to 100 parts by weight of the solid content of EPAE is in the range of 5 to 50 parts by weight. That is, it means that the epoxy resin is used for the emulsion core layer. Preferably it is in the range of 10 to 30 parts by weight. If less than 5 parts by weight, water resistance, warm water resistance,
Insufficient boiling resistance, heat resistance, and the like are caused. When the amount is more than 50 parts by weight, stability cannot be obtained at the time of emulsion polymerization of the core layer, which causes a problem in production. The glass transition temperature (Tg) (hereinafter abbreviated as Tg) of EPAE of the present invention is -20 to + 30 ° C.
, More preferably in the range of -5 to + 5 ° C. −
When the temperature is lower than 20 ° C., the adhesive strength, boiling resistance and heat resistance are lowered, and when the temperature is higher than + 30 ° C., the emulsion film is not formed uniformly at low temperature. Incidentally, Tg expressed in the present invention means a value calculated from all monomers excluding the epoxy resin. Tg of core layer of EPAE of the present invention
Is in the range of −10 to +60, preferably 0 to 50 ° C.
Range. When the temperature is lower than -10 ° C, boiling resistance and heat resistance cannot be obtained, and when the temperature is higher than + 60 ° C, the adhesive strength decreases. Similarly, the Tg of the shell layer is −40 to + 10 ° C.
And preferably in the range of -30 to + 5 ° C. When the temperature is lower than -40 ° C, adhesive strength, boiling resistance and heat resistance cannot be obtained, and when the temperature is higher than + 10 ° C, an emulsion film cannot be formed uniformly at a low temperature. The weight ratio of monomers used for the core layer and the shell layer of EPAE is not particularly limited, but the preferred core-shell composition ratio is 7%.
/ 3 to 3/7.

Examples of the curing agent (b) for an epoxy resin include aromatic amines, aliphatic amines, heterocyclic modified amines, amines such as polyamides, polysulfides, and acid anhydrides. Among these, although not particularly limited, those which can be freely diluted with water or those which can be made into an aqueous emulsion or an aqueous dispersion are preferable in view of mixing with an aqueous emulsion. The mixing ratio of the epoxy resin curing agent is preferably 5 to 25 parts by weight, more preferably 7 to 5 parts by weight, based on 100 parts by weight of the solid content of EPAE.
It is in the range of 15 parts by weight. When the amount is less than 5 parts by weight, a sufficient cured product of the adhesive cannot be obtained, and the adhesive strength, water resistance, hot water resistance, and boiling resistance are lacking. When the amount is more than 25 parts by weight, the odor of the adhesive and the skin Obstacles, yellowing, reduced solids, and even excess epoxy curing agent can exhibit a plasticizing effect and reduce adhesion.

[0011] Cement paste is a mixture of one or more inorganic aggregates such as calcium carbonate, silica, talc and clay in cement typified by Portland cement, and water-soluble fibers such as methyl cellulose and sodium cellulose glycolate. Element and water-soluble synthetic resin powder such as polyvinyl alcohol, water and synthetic rubber latex, vinyl acetate emulsion, vinyl acetate copolymer emulsion, acrylic emulsion, epoxy emulsion, urethane emulsion and other aqueous resin emulsions It is a cement paste comprising a water-based emulsion represented by a compound such as a water reducing agent represented by a sulfonated melamine resin, and in the present invention, these compositions are not particularly limited. 20-75% of the formulation is essential in object. As described above, the one-part curable aqueous emulsion obtained by blending the EPAE and the epoxy curing agent can be stored even though the glycidyl group and the carboxyl group and the curing agent for the epoxy resin coexist in the emulsion particles. It is excellent in stability, it is applied as a sealer on the surface of wood-based boards, fibrous boards and inorganic boards as a sealer, and then a cement paste is applied and dried on it. Excellent adhesiveness between pastes and excellent water resistance, hot water resistance, boiling resistance, impact resistance, etc., so it has durability against wind, rain, fire, water discharge, earthquake, etc. Practical value is extremely high as a method for producing.

[0012]

EXAMPLES The present invention will be described below with reference to Production Examples, Examples and Comparative Examples, but it should not be construed that the invention is limited thereto.
In the examples, parts and percentages are by weight unless otherwise specified.

Production Examples 1 to 9 A mixture of 100 parts of the mixed monomer for the core and shell layers having the composition ratios shown in Table 1 and a chain transfer agent were weighed in advance, and 50 parts of distilled water and 0.1% of sodium dodecylbenzenesulfonate were respectively measured. Into 5 parts was added dropwise under stirring conditions to obtain a pre-emulsified monomer. Separately, 100 parts of distilled water and 0.2 parts of sodium dodecylbenzenesulfonate are charged into a 1-liter flask, and the temperature is raised to 70 ° C. while stirring under a nitrogen seal, and 0.5 parts of potassium persulfate and an emulsion are seeded. For this purpose, 0.5 part of a mixed monomer of n-butyl acrylate, methyl methacrylate and hydroxyethyl methacrylate in a ratio of 1: 1: 1 was charged and reacted for 20 minutes to form an emulsion nucleus. Subsequently, the pre-emulsifying monomer for the core was continuously dropped over 3 hours, and the remaining monomer was reacted for 2 hours after completion of the dropping. Subsequently, the emulsifying monomer for shell was added dropwise over 3 hours in the same manner as described above, and the remaining monomer reaction was carried out at the same temperature for 3 hours.
After blending the epoxy resin curing agent shown in Table 1, the mixture was filtered through a 100-mesh wire gauze to obtain a one-part curable aqueous emulsion having a solid content of 50% used in the present invention.

[0014]

[Table 1]

Production Examples a to c After mixing calcium carbonate, methylcellulose and polyvinyl alcohol with Portland cement in the proportions shown in Table 2, the aqueous emulsion and water shown in the table were added and kneaded sufficiently to obtain a cement paste. I got

[0016]

[Table 2]

Examples 1 to 11 The one-part curable aqueous emulsions obtained in Production Examples 1 to 9
The surface of the thick type 1 plywood was applied as a sealer with a roll coater at 150 g / m ^{2 and} dried in a 120 ° C. hot air drier for 3 minutes. Next, 1500 g / m ^{2 of} the cement paste obtained in Production Examples a to c was applied using a roll coater, and 80 ° C.
After drying with a hot air drier for 20 minutes, it was left to cure at room temperature for 48 hours to obtain an architectural base material of the present invention. This material was cut into 5 × 5 cm squares and subjected to an evaluation test as described below.
It was shown to.

(1) Stability test of one-part curable aqueous emulsion (sealer) The one-part curable aqueous emulsion obtained in Production Examples 1 to 9 was subjected to 40 tests.
After storing at room temperature for 2 months, cooling at room temperature, comparing the viscosity immediately after blending with the viscosity after aging, and comprehensively evaluating the presence or absence of residue (aggregate) when filtered through a 100 mesh wire mesh,
Displayed as follows. ○ No change in viscosity and no residue was observed. △ Doubled the initial viscosity but no residue. × Viscosity was twice or more, or unfilterable residue was generated.

(2) Adhesion test The front and back sides of the sample (the Instron tensile test jig was attached to the surface of the plywood and the cured cement), and the plane tensile strength was evaluated at the pulling speed of 3 mm / min. /
The intensity was shown per cm ² . a) Normal adhesive strength → Measured in a high temperature room at 23 ° C and 65% humidity. b) Water resistance → Immediately after immersion in water for 168 hours, measured under a) conditions. c) Warm water resistance → Immediately after immersion in 60 ° C warm water for 4 hours,
a) Measured under conditions. d) Boiling resistance → Immerse in boiling water for 4 hours, cool to room temperature, and measure under a) conditions.

(3) Impact resistance The same location of the sample was impacted three times with an Izod impact tester, and the impact location of the cured cement paste was visually observed.
Displayed as follows. NB Not destroyed CB Hardened cementitious product intermediate layer destroyed PS Hardened cementitious material dropped from sealer interface.

Comparative Example 1 An EPAE was prepared using the mixture of the core and shell monomers used in Production Example 1 in accordance with the emulsion polymerization method for the core layer of Production Example 1. A mixture containing the same curing agent for epoxy resin was used as a sealer in the same manner as in Example 1, and was carried out in accordance with Example 1, and the evaluation results are shown in Table 3.

Comparative Example 2 Example 1 was replaced with a one-part curable aqueous emulsion by MB.
R latex (trade name: Struct Bond 2031, trade name: Mitsui Toatsu Chemicals, Inc., solid content 46%, PH 7, viscosity 100 cps, methyl methacrylate-butadiene copolymer latex) 10
Epolsion EA-3 (product of Kanebo-NSC Co., Ltd., 50% solid content,
The procedure was performed in the same manner as in Example 1 except that a mixture of 10 g of viscosity 100 cps, epoxy equivalent 900) and 10 g of Epolsion EB-1 (a product of Kanebo-NSC, 45% emulsion of modified aliphatic amine) was used as a sealer. Table 3 shows the results of the evaluation.

Comparative Example 3 An acrylic emulsion (Almatex E-175, trade name of Mitsui Toatsu Chemicals, Inc., solid content 45%, PH8, viscosity 1000 cps, Tg) was used in place of the one-part curable aqueous emulsion used in Example 1. -10 ° C, styrene 2-ethylhexyl acrylate copolymer emulsion) was used in the same manner as in Example 1, and the evaluation results are shown in Table 3.

[0024]

[Table 3]

[0025]

As is clear from the evaluation results in Table 3, the one-part curable aqueous emulsion of the present invention has excellent storage stability, and is used as a sealer on the surfaces of wood-based boards, fiber-based boards, and inorganic-based boards. After coating and drying, in the manufacture of a building base material for applying and drying a cement paste material thereon, the adhesiveness between the base board and the cement paste material is excellent, and water resistance, hot water resistance, boiling resistance and Since it is excellent in impact resistance and the like, it is extremely effective as a method for producing a building base material having long-term durability against wind, rain, water discharge in a fire, earthquake, and the like.

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-60-78735 (JP, A) JP-A-55-158184 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) B32B 1/00-35/00

Claims (5)

(57) [Claims] The core layer is a copolymer of an aromatic vinyl monomer, an unsaturated carboxylic acid ester monomer, an acrylic monomer having an amide group and an epoxy resin, and the shell layer is an aromatic vinyl monomer, an unsaturated carboxylic acid ester. A curing agent (b) for an epoxy resin is previously added to an epoxy-modified acrylic emulsion (a) having a core-shell structure, which is a copolymer of a monomer, an acrylic monomer having a hydroxyl group, an acrylic monomer having an amide group, and a monomer having a carboxyl group. The one-part curable aqueous emulsion obtained by blending is applied as a sealer to the surface of a wood-based board, a fibrous board or an inorganic-based board as a sealer, and then a cement paste is applied thereon and solidified. Manufacturing method of building base material. 2. The architectural base material according to claim 1, wherein the epoxy-modified acrylic emulsion is obtained by copolymerizing 5 to 50 parts by weight of an epoxy resin in 100 parts by weight of the solid content of the emulsion. Manufacturing method. 3. The method according to claim 1, wherein the glass transition temperature (Tg) of the epoxy-modified acrylic emulsion is in the range of −20 to + 30 ° C. 4. The glass transition temperature (Tg) of the core layer of the epoxy-modified acrylic emulsion is in the range of −10 to + 60 ° C., and the glass transition temperature (Tg) of the shell layer is in the range of −40 to + 10 ° C. A method for producing a building base material according to claim 1. 5. A one-part curable aqueous emulsion comprising a solid content of 5 to 25 parts by weight of a curing agent for an epoxy resin per 100 parts by weight of a solid content of an epoxy-modified acrylic emulsion. A method for producing a building base material according to claim 1.