JPS6160875B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to an adhesive composition for covering a building base, and particularly to an adhesive composition that does not require priming of the base when a covering material such as wallpaper or cloth is attached to a water-absorbing inorganic base. mortar, concrete, calcium silicate board,
Dolomite plaster, gypsum plaster, PC
On a water-absorbing inorganic base made of board, slate board, etc.
When pasting wallpaper, cloth, etc., if you use a water-soluble resin adhesive such as starch to directly paste the covering material on the base, sufficient adhesive strength may not be obtained and peeling may occur over time, or There was a problem that during construction, the moisture in the adhesive was rapidly absorbed into the base, making it difficult to match the pattern of the facing material. Because of this problem, when turning on a water-absorbing inorganic base as described above, use a synthetic resin emulsion such as a modified vinyl acetate resin emulsion, an ethylene-vinyl acetate copolymer resin emulsion, or an acrylic ester resin emulsion as the base in advance. Alternatively, a turning method is used in which a solution of an organic solvent such as modified vinyl acetate resin, epoxy resin, or polyurethane is applied as a base coat, and after the base coat dries, a facing material is applied using a water-soluble resin adhesive such as starch. was. By applying a primer treatment to a water-absorbing inorganic base in this way, it reduces the water absorption of the base, suppresses the brittleness of the surface, suppresses the powderiness of the surface, and improves the water resistance, alkali resistance, and creep resistance of the adhesive. It can be expected to have effects such as providing adhesive strength, increasing adhesive strength, accelerating drying, and improving initial adhesive strength. However, the following various problems exist in this lathing method that performs undercoating. (1) Since two steps are required: undercoating (drying) and adhesion (drying), a long turning period is required. (2) The cost of primer and the labor cost required for its application will increase. (3) When using a solvent-based primer, there is a problem of fire during turning and contamination of the working environment due to the solvent that volatilizes. (4) Adhesion between primer and adhesive is not necessarily good. (5) Depending on the type of base, it is necessary to use an emulsion-based or solution-based primer, making the selection complicated. (6) If left for a long time after undercoating, dirt and dust will adhere to the treated surface, and adhesion will become difficult if the undercoat is only slightly dry, so it is necessary to control the length of time the undercoat is left. It is an object of the present invention to
In order to eliminate the drawbacks of the turning method which requires two steps of adhesion, the object of the present invention is to provide an adhesive composition that can exhibit the same adhesive strength without the use of an undercoat. Considering that an emulsion such as a thermoplastic resin is used as the primer mentioned above and a solution-based adhesive of a water-soluble resin is used as the adhesive, water is used as a medium to disperse these thermoplastic resins and water-soluble resins. It is conceivable to use a one-component adhesive that is present in a dissolved state. However, in such coexisting adhesives, although the water-soluble resin penetrates into the water-absorbing inorganic base, it is not possible to completely suppress the brittleness beneath the surface of the base, and sufficient adhesive strength cannot be obtained. However, according to the research of the present inventors, when mixing a water-soluble resin solution with such an emulsion, by simultaneously making a chelate-forming water-soluble resin exist, the above-mentioned drawbacks of coexisting adhesives can be overcome. It was discovered that it can be resolved. Therefore, the aqueous adhesive composition of the present invention is characterized by containing a thermoplastic resin or rubber emulsion, a water-soluble resin, and a chelate-forming water-soluble resin. The present invention will be explained in more detail below. As mentioned above, the adhesive composition of the present invention can be applied to mortar, concrete, calcium silicate board, dolomite plaster, gypsum plaster, PC board,
Wallpaper on a water-absorbing inorganic base made of slate board, etc.
It is particularly suitable for pasting sheet-like covering materials such as cloth. These bases have properties such as high water absorption, brittle and powdery surfaces, and strong alkalinity. The adhesive of the present invention is usually used by applying it to the back side of a sheet-like facing material and pasting it to the base, but it is also possible to apply it directly to the base and affixing the facing material while it is still wet. It is. The adhesive of the present invention is made by dissolving or dispersing thermoplastic resin or rubber emulsion particles, a water-soluble resin, and a chelate-forming water-soluble resin in water as a medium. Thermoplastic resin or rubber emulsion has the effect of suppressing brittleness on the water-absorbing inorganic base surface, filling small unevenness on the surface, eliminating glue gaps, and increasing adhesive strength by increasing the bonding area. has. Examples of suitable thermoplastic resins include polyvinyl acetate resins; modified polyvinyl acetate resins modified with unsaturated organic acids such as acrylic acid, methacrylic acid, maleic acid, crotonic acid; vinyl acetate and ethylene, vinyl chloride, acrylic acid; Or a copolymer resin with methacrylic acid ester, etc.; polyacrylic acid or methacrylic acid ester resin, etc. may be mentioned. Examples of suitable rubbers include synthetic rubbers such as styrene-butadiene rubber, acrylonitrile-butadiene rubber, butadiene rubber, and chloroprene rubber;
Examples include modified synthetic rubbers modified with unsaturated organic acids such as fumaric acid and esters thereof. Thermoplastic resins as well as rubbers are substantially water-insoluble.
In the present invention, the term "emulsion" is used in a broad sense to include latex. The thermoplastic resin or rubber (hereinafter collectively referred to as "emulsion resin") that forms these emulsions is used in a solid content of 25 to 240 parts per 100 parts by weight (the same applies hereinafter) of water. If the amount is less than 25 parts, the adhesive strength of the composition will be extremely reduced, and 240 parts
If the amount exceeds 100%, the coating properties of the composition will be significantly reduced when a water-soluble resin is added. Water-soluble resins also provide water-retaining properties to the composition and properties that suppress subsurface brittleness of water-absorbing inorganic substrates. Examples include methylcellulose, polyacrylate, alginate, casein, etherified starch, esterified starch, dextrin, gelatinized starch, polyvinylpyrrolidone, cationized starch, and the like. These water-soluble resins are used in an amount of 0.1 to 20 parts, preferably 1 to 5 parts, based on 100 parts of the emulsion resin. If it is less than 0.1 part, it will not be able to penetrate into the base and prevent the brittleness of the surface, and if it exceeds 20 parts, the coating property will be significantly reduced and it cannot be used in practice. The chelate-forming water-soluble resin has the effect of enhancing the adhesive strength of the composition and the effect of penetrating into the water-absorbing inorganic base to suppress subsurface brittleness that could not be completely suppressed with the water-soluble resin alone. Examples include isoptylene-maleic anhydride copolymer resin, styrene-maleic anhydride copolymer resin-vinyl acetate-maleic anhydride copolymer resin, and unsaturated polyhydric acids such as maleic acid and fumaric acid. and copolymers such as unsaturated monomers that can be copolymerized with this. The reason why the chelate-forming resin is required to be water-soluble is that it needs to sufficiently penetrate into the interior of the water-absorbing inorganic base. These chelate-forming water-soluble resins are used in an amount of 0.1 to 20 parts, preferably 1 to 20 parts, per 100 parts of emulsion resin.
Use in an amount of 10 parts. If the amount is less than 0.1 part, the above-mentioned effects such as enhancing adhesive strength will be poor, and if it is used in excess of 20 parts, the coating property will be significantly reduced and it is not practical. The above-mentioned water-soluble resin and chelate-forming water-soluble resin are usually supplied in the form of a mixture with the emulsion resin. A similar effect can be obtained in terms of form. The composition of the present invention has the above-mentioned components as essential components, but in addition to these, fillers such as calcium carbonate, aluminum hydroxide, carbon black, bentonite, talc, and kaolin; Antiaging agents such as phenol, amine, and phosphate esters to prevent aging and deterioration of resin components due to heat, light, or oxygen; other additives that are normally added to adhesives such as pigments and plasticizers. can be added optionally and in the amounts normally used. The adhesive of the present invention can be obtained by uniformly mixing the above-mentioned components in an aqueous medium, but preferably in the form of an aqueous solution or dispersion of a thermoplastic resin or rubber emulsion and other components as necessary. The method of adding and mixing is used. As mentioned above, it is possible to adopt the form of graft polymerization in this case. As described above, the adhesive of the present invention has the following excellent properties when attaching a facing material to a water-absorbing inorganic base. (1) Since lathing can be done in one step without the need for undercoating, the construction period can be shortened. (2) Since lathing can be done in one step, it is possible to reduce the overall construction cost, including the material cost for the adhesive and the labor cost. (3) Since no solvent is used, it is favorable from the viewpoint of safety and working environment. (4) Because it has good water retention, it is possible to match the pattern of the facing material during turning without applying an undercoat. (5) Almost the same adhesive strength can be obtained when undercoating is applied. The present invention will be explained in more detail with reference to Examples below. Example 1 Polyvinyl as a water-soluble resin was added to 100 parts of ethylene-vinyl acetate copolymer resin emulsion (solid content, 50% by weight, EVADICEP-1 manufactured by Dainippon Ink and Chemicals) (as solid content, the same applies to the resin below). 2 parts of alcohol (saponification degree, 88%, PA-18 manufactured by Shin-Etsu Chemical Co., Ltd.), 4 parts of styrene-maleic acid copolymer resin (manufactured by Showa Kobunshi Co., Ltd., Kogam KB-2401) as a chelate-forming water-soluble resin. and stirred and mixed until the whole was in a uniformly dispersed state. Furthermore, 2 parts of bentonite and 50 parts of calcium carbonate were added as fillers and thoroughly mixed to obtain a composition of the present invention (composition (1)) (the total water content was about 130 parts). The composition obtained in this way was applied to a calcium silicate plate (Asbestostrax manufactured by Nippon Asbestos Co., Ltd.).
Apply at a rate of approximately 83g/m ² (as solid content) to
Paste cotton cloth (JIS L0803 Cotton No. 3) and heat at 20℃ for 48
The adhesive strength was measured after time drying. The above operation was repeated by changing the type of adhesive and adding an undercoat treatment. These results are shown in Table 1 below.

[Table] As is clear from Table 1 above, sufficient adhesive strength cannot be obtained with conventional vinyl acetate resin emulsion type adhesives without undercoating (Comparative Example 1)
In contrast, the adhesive composition of the present invention (Example 1)
Even without undercoating, adhesive strength equivalent to that obtained by undercoating with an epoxy resin solution type undercoat (Comparative Example 2) was obtained, and compared to when treated with an ethylene-vinyl acetate resin emulsion type undercoat. This results in much better bond strength. Example 2 Vinyl acetate-Beova copolymer resin emulsion (solid content 50% by weight, VL-2 manufactured by Showa Kobunshi Co., Ltd.) 100
(solid content), 3 parts of CMC (AP-H manufactured by Nippon Chemical Industry Co., Ltd.), 25 parts of isobutylene-maleic anhydride copolymer resin (Isoban-110 manufactured by Kuraray Co., Ltd.), and 50 parts of calcium carbonate as a filler. , 0.2 parts of sodium hexametaphosphate was added as a dispersant,
The adhesive composition of the present invention (composition
(2)) was obtained. Using this composition, an adhesive strength test between mortar and cotton cloth was conducted in the same manner as in Example 1. In addition, adhesive strength tests were conducted using different adhesives and undercoating, and the results are summarized in Table 2 below.

[Table] As shown in Table 2, even when using conventional vinyl acetate resin emulsion type adhesives without a base coat, it provides much stronger adhesion to mortar than when using calcium silicate plates. (Comparative Example 5)
However, due to the high water absorption of mortar, it was difficult to match the patterns of cloth, wallpaper, etc. On the other hand, when the composition of the present invention was used (Example 2), it showed an adhesive force equal to or higher than that when undercoated (Comparative Example 6) and had excellent water retention, so it It was possible to match the patterns of cloth, wallpaper, etc.

Claims (1)

[Claims] 1 emulsion of thermoplastic resin or rubber, water-soluble resin, isobutylene, maleic anhydride copolymer resin, styrene, maleic anhydride copolymer resin, vinyl acetate, maleic anhydride copolymer resin,
and a chelate-forming water-soluble resin selected from a copolymer of an unsaturated polyacid and an unsaturated monomer copolymerizable therewith.