JPH0762129B2 - Tile bonding method - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for adhering tiles, and more specifically, in the production of a tile wall panel mainly composed of a unit bath in which a tile is adhered to a cement board, good initial fixing property is obtained. In addition, the present invention relates to a method for safely adhering tiles.

Prior Art and Problems to be Solved Unit bath tile wall panels are generally manufactured by adhering ceramic or magnetic tiles to cementitious boards such as calcium silicate boards and flexible boards. Conventionally, a two-component epoxy resin adhesive has been used for this adhesion, and a method of applying the adhesive to a cement-based board with a spatula, a cusgote, a roll coater, a hand gun, etc., and attaching a tile to this is performed. ing. However, in this bonding method, since the adhesive used generally has a low viscosity in consideration of the mixing operation of the two liquids, the initial fixing property of the tile is not good. In addition, since organic amines are used as curing agents or catalysts, they cause skin irritation and rash due to their irritation, and it is necessary to improve the environment such as exhaust equipment in terms of safety. If there is cracking or peeling of the tiles due to this, there is a problem.

On the other hand, there is a market record in the method of using a low-viscosity, moisture-curing one-component urethane adhesive and applying this with a roll coater, but the tile's initial fixability is poor due to its low viscosity, and Continuous compression is required during this period, resulting in poor work efficiency.

The inventors of the present invention have made extensive studies to solve the problem of the tile bonding method, and as a result, thixotropic moisture-curable overnight type urethane containing two types of urethane prepolymers containing active isocyanate groups which are incompatible with each other. We have completed the present invention by finding that the use of a system adhesive significantly improves the initial fixing property of tiles, the compression time is only a few seconds, and the safety concerns such as skin irritation are largely eliminated. I was allowed to do it.

Structure and effect of the invention That is, the present invention, when bonding the tile to the cement-based board, using thixotropic moisture-curable one-component urethane-based adhesive, the adhesive is compatible with each other, which will be described in detail below. A tile adhering method characterized in that it is a thixotropic moisture-curable one-component type urethane adhesive having a specific viscosity in which two types of urethane prepolymers containing active isocyanate groups are dispersed in a specific weight ratio. is there.

The adhesive used in the present invention is an active isocyanate group-containing urethane prepolymer obtained by reacting a polyether polyol and an excess polyisocyanate compound (hereinafter,
NCO-containing polyether prepolymer))
Normally, a system in which a urethane prepolymer containing an active isocyanate group (hereinafter referred to as an NCO-containing polyester prepolymer), which is incompatible with a CO-containing polyether prepolymer and is obtained by reacting a polyester polyol with an excess polyisocyanate compound, is dispersed, is usually used. Thixotropic agents (anhydrous silica powder, bentonite, etc.) are blended to impart thixotropy, and if necessary, various additives such as fillers (calcium carbonate, talc, clay, carbon, silicic acid anhydride, metal). Powder, etc., plasticizer (dioctyl phthalate,
Butylbenzyl phthalate, dinonyl phthalate and other phthalates, diethylene glycol dibenzoate, ethylene glycol monobutyl ether benzoate and other benzoates, partially hydrogenated terphenyl, alkyl polycyclic aromatic hydrocarbons, chlorinated paraffins, etc.) , Solvent (aromatic hydrocarbons such as toluene and xylene, esters, ketones, ethers, etc.),
Catalyst for curing acceleration (N-alkylbenzylamine, N-alkylmorpholine, N-alkylaliphatic polyamine, N
-Alkylpiperazine, triethylenediamine, tin,
Naphthenates or octenoates of heavy metals such as lead, cobalt, manganese and iron, dibutyltin dilaurate,
Dibutyltin maleate, etc.), antioxidant, UV absorber, dye, pigment, water-absorption agent (calcium oxide, molecular sieves, etc.) It has a high viscosity of cps / 20 ℃ and reacts with moisture in the air to form a cured film.

Examples of the polyether polyol in the NCO-containing polyether prepolymer include low molecular weight active hydrogen compounds having two or more active hydrogens (for example, diols such as ethylene glycol, propylene glycol, butylene glycol, 1,6-hexanediol, and glycerin). , Trimethylolpropane, triols such as 1,2,6-hexanetriol, ammonia, amines such as methylamine, ethylamine, propylamine and butylamine) and propylene oxide and ethylene oxide in the presence of one or more of them. Random or block copolymer polyoxyethylene-propylene polyol (particularly a polyol with ethylene oxide of 30 mol% or less is desirable) obtained by ring-opening polymerization of Examples of the polyoxytetramethylene glycol obtained by the combination include those having a molecular weight of 300 to 7,000 and 2 to 4 OH-containing one molecule. Examples of the polyisocyanate compound to be reacted with the polyether polyol include hexamethylene diisocyanate, aliphatic polyisocyanates such as lysine methyl ester diisocyanate, hydrogenated diphenylmethane diisocyanate, isophorone diisocyanate, and hydrogenated tolylene diisocyanate. Cyclic polyisocyanates, tolylene diisocyanate (TDI), diphenylmethane diisocyanate (M
DI), aromatic isocyanates such as naphthylene diisocyanate, xylylene diisocyanate, and mixtures thereof. Particularly preferred polyisocyanate compounds are aromatic polyisocyanates,
For example, TDI and MDI are preferably used. Polyether polyol and excess polyisocyanate compound, that is, 1.3 ≦ NCO / OH so that the active isocyanate group (NCO) of the polyisocyanate compound is greater than 1 with respect to the hydroxyl group (OH) of the polyether polyol.
By reacting at 70 to 100 ° C for several hours at a ratio of ≤10, NCO with a normal NCO content of 1 to 15% (wt%, the same applies hereinafter)
A CO-containing polyether prepolymer is obtained. In this reaction, a usual catalyst, plasticizer or solvent may be used.

It is important that the NCO-containing polyester prepolymer is not compatible with the NCO-containing polyether prepolymer (otherwise the thixotropic stability of the adhesive is impaired, for example sagging over time). From the viewpoint, for example, aromatic polybasic acids (phthalic acid, terephthalic acid, isophthalic acid, or dialkyl esters thereof) as the polyol component and polyhydric alcohols (the same diols and triols as described above, diethylene glycol, triethylene, etc. (Includes glycol, dipropylene glycol, tripropylene glycol, etc.)
A polyester polyol obtained by reacting
It is produced by reacting a polyisocyanate compound with a molecular weight of 300 to 3000, 2 to 4 containing OH in one molecule) under the same conditions as in the case of the NCO containing polyether prepolymer, which is also usually NCO content 1-15
% Has been adjusted.

The weight ratio of the NCO-containing polyether propolymer to the NCO-containing polyester prepolymer is usually selected within the range of 95/5 to 50/50, preferably 90/10 to 70/30. If the ratio of the NCO-containing polyester prepolymer is less than 5%, stable thixotropy cannot be obtained, and if it exceeds 50%, a reversal phenomenon of the prepolymer / prepolymer sea-island structure is observed, and the initial physical properties are That is, the adhesiveness, elongation and durability tend to be reduced.

The tile adhering method according to the present invention can be carried out in the following procedure.

To the cement-based board of the adherend, the above thixotropic high-viscosity moisture-curable one-component urethane adhesive is used with a cusigote or a dedicated automatic bead applicator, 2-3 mmφ, 5-20 pieces / 10
Apply in the form of a bead of cm (application amount 300 to 1000 g / m ² ), or
Alternatively, after multi-point coating using a multi-spreader, tiles are stuck to this and pressure-bonded for several seconds at a pressure of usually 0.02 to 2.0 Kg / cm ² , preferably 0.1 to 0.2 Kg / cm ² . In this state, curing may be performed as it is, or joint cement may be added immediately.

As described above, according to the method of the present invention, it is not necessary to mix the two liquids of the adhesive, and since the high-viscosity non-sag type adhesive is used, the initial fixing property of the tile is very good, and the pressure after the tiles are adhered to each other. The tightening can be completed under mild conditions.

Next, the present invention will be described more specifically with reference to Examples and Comparative Examples.

Example 1 (1) NCO-containing polyether prepolymer Polyoxypropylene diol (Takeraku P-21, molecular weight 2000, manufactured by Takeda Pharmaceutical Co., Ltd.) 100 g, DOP as a plasticizer
(Dioctyl phthalate) 100g and MDI 100g, 80 ℃
After reacting for 5 hours, NCO content 9.8%, viscosity 2000cps /
An NCO containing polyether prepolymer at 20 ° C. is obtained.

(2) NCO-containing polyester prepolymer terephthalic acid-based polyester diol (Adekanyuace YG-214, manufactured by Asahi Denka Co., Ltd., molecular weight 2000) D to 100 g
Add OP100g and MDI100g, react at 80 ℃ for 5 hours, N
An NCO-containing polyester prepolymer having a CO content of 9.8% and a viscosity of 10,000 cps / 20 ° C. is obtained.

(3) Thixotropic moisture-curing one-pack type urethane adhesive To 90 g of NCO-containing polyether prepolymer of (1) above, 10 g of NCO-containing polyester prepolymer of (2) above was added and well stirred to obtain a dispersion. . Next, 100 g of pre-dried calcium carbonate and 8 g of ultrafine particle anhydrous silica (Nippon Aerosil Co., Ltd., Aerozil 200) were added, and a curing catalyst, an adhesive, a thickener, etc. were further added, and the mixture was thoroughly stirred and then defoamed. Thixotropic moisture-curable one-component urethane adhesive (viscosity 100,000
cps / 20 ° C).

(4) Tile Adhesion Using the adhesive of (3) above, cement-based boards and ceramic tiles (98 mm square, manufactured by DANTO) were bonded. That is, using a comb iron on a flexible board, 2.5m
Apply the adhesive in mφ bead shape and attach ceramic tiles. Immediately after bonding, the bonded panel
Tighten at a pressure of 0.1 Kg / cm ² for 10 seconds, and after decompressing, make vertical 40
When it was cured for 3 hours in an atmosphere of ° C, the tiles were not displaced.

Example 2 Tiles were attached to a flexible board in the same manner as in (4) of Example 1, and the cement for joints prepared in advance was applied to the tile joints immediately after crimping, and movements such as displacement of the tiles were observed at that time. I couldn't do it. After that, 3 at 40 ℃
After curing for a while, a tile panel was obtained.

Example 3 According to (3) of Example 1, a thixotropic moisture-curable one-component urethane adhesive having a viscosity of 1,000,000 cps / 20 ° C. was prepared and a tile panel was prepared using a dedicated automatic coating device. I went. That is, using a 59: 1 pump (manufactured by Pires Co., Ltd.), 81 adhesives in the longitudinal direction of a board of 3 x 6 (90 x 180 cm) size with a 3 mmφ and 10 mm pitch from a dedicated porous nozzle. / A bead of width was applied and ceramic tiles were laminated. Immediately after bonding, the bonded panel is pressed with a pressure of 0.1 Kg / cm ²
It was clamped for 0 seconds, decompressed, and then verticalized, and cured in an atmosphere of 40 ° C. for 3 hours.

Comparative Example 1 NCO-containing polyether prepolymer 1 of (1) of Example 1
To 00g, add 100g of pre-dried calcium carbonate, further add curing catalyst and adhesive, stir well and defoam,
A moisture-curing one-component urethane adhesive with a viscosity of 100,000 cps / 20 ° C without thixotropy is obtained.

The above-mentioned thixotropic adhesiveness was applied to a flexible board using a comb iron, ceramic tiles were pasted together, and immediately pressed with a pressure of 0.1 Kg / cm ² for 10 seconds, but transfer to the next step. Misalignment and floating occurred on the tiles.

Adhesive N composed of the parts by weight shown in Table 1 below
o.1 to 4 are attached to a thixotropic stabilization test [a mill test after 7 days at 50 ° C. is performed to measure the length of sagging (mm)], and the results are also shown in Table 1. The urethane prepolymers used are those produced in (1) and (2) of Example 1, respectively.

Claims (2)

[Claims] 1. A thixotropic moisture-curing one-component urethane adhesive is used for adhering a tile to a cement board,
The adhesive is obtained by reacting a polyether polyol and an excess polyisocyanate compound with an active isocyanate group-containing urethane prepolymer obtained by reacting a polyester polyol and an excess polyisocyanate compound which are incompatible with the urethane prepolymer. The active isocyanate group-containing urethane prepolymer obtained by
Viscosity 50,000-150 dispersed to 95 / 5-50 / 50
A tile adhering method characterized by being a thixotropic moisture-curing one-pack type urethane adhesive at 10,000 cps / 20 ° C. 2. The method according to claim 1, wherein the adhesive is bead-coated or multi-point coated.