JPH06287544A - Joint-sealing composition for gypsum board, method for sealing joint, and gypsum board aggregate - Google Patents

Abstract

PURPOSE:To obtain a joint-sealing compsn. which can easily form a joint hardly causing thickness decrease or cracks by compounding gypsum hemihydrate, a resin having a specified glass transition point, and a fibrous material. CONSTITUTION:This compsn. comprises, on solid base, 10-93wt.% gypsum hemihydrate, 6-15wt.% resin having a glass transition point of -10 deg.C or lower, and 0.5-1wt.% fibrous material. Gypsum hemihydrate (CaSO4.1/2H2O), when mixed with water, hydrates and converts to gypsum dihydrate (CaSO4.2H2O). Gypsum dihydrate derived from the hemihydrate is minute needle crystals, which cross each other, exhibiting an apparent expandability and preventing the thickness decrease at a joint. The resin imparts extensibility to the joint and retards the occurrence of cracks at the joint. The compsn. may further contain a filler, a solvent, a viscosity-adjusting agent, and other additives.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a joint treatment composition, a joint treatment method and an aggregate, and more particularly to a joint treatment composition for gypsum board, a joint treatment method using the same and a gypsum board aggregate.

[0002]

2. Description of the Related Art Gypsum board is used as an inner wall material for forming an inner wall or a ceiling of a building. When forming the inner wall of the room with gypsum board, a large number of gypsum boards are arranged in a plane and fixed to the wall surface, and joint treatment is performed between the gypsum boards. A conventional joint structure will be described with reference to FIG. In the figure, the gypsum boats 1 arranged side by side
A V-shaped groove 2 is formed between a and 1b. A joint portion 3 is formed in this groove 2. Joint 3
Has a joint putty layer 4, a joint tape layer 5, a joint putty layer 6 and a finishing putty layer 7 in order to prevent thinning and maintain the smoothness of the surface and to prevent the occurrence of cracks. It is usually formed in a four-layer structure. According to the joint portion 3 as described above, the joint putty layer 6 suppresses thinning, and the joint tape layer 5 suppresses the occurrence of cracks.

[0003]

The above-mentioned conventional joint portion 3
Has a complicated four-layer structure as described above, and therefore the forming work is complicated. Also, the joint putty layer 4 and the joint putty layer 6
The function of preventing thinning due to and the function of preventing generation of cracks due to the joint tape layer 5 are insufficient. An object of the first invention is to provide a joint treatment composition for gypsum board, which can easily form joints which are less likely to cause meat thinning and cracks.

An object of the second, third and fourth inventions is to easily form joints which are less likely to cause skin thinning and cracks. It is an object of the fifth and sixth inventions to simplify the structure of the joint portion of the gypsum board and to prevent cracks and thinning from occurring easily.

[0005]

The joint treatment composition for gypsum board according to the first invention comprises hemihydrate gypsum as one of the total solid components.
0 to 93% by weight, a resin having a glass transition point of -10 ° C or lower in an amount of 6 to 15% by weight of the total solid content, and a fibrous substance in an amount of 0.5 to 1% by weight of the total solid content. There is. The joint treatment method according to the second aspect of the present invention is a method for forming joints in grooves formed between gypsum boards. This method includes the following steps. A step of preparing a first agent containing a resin having a glass transition point of −10 ° C. or lower and a fibrous substance. ◎ Step of preparing a second agent containing hemihydrate gypsum. ◎ Hemihydrate gypsum is contained in a proportion of 10 to 93% by weight of the total solid content component, resin is contained in a proportion of 6 to 15% by weight of the total solid content component, and fibrous substance is contained in a proportion of 0.5 to 1% by weight of the total solid content component. A step of mixing the first agent and the second agent to prepare a joint treatment agent. ◎ The process of filling the joint between the gypsum boards with the joint treatment agent.

The joint treatment method according to the third invention is for forming joints in the grooves formed between the gypsum boards. This method includes the following steps. ◎ Hemihydrate gypsum is 10 to 93% by weight of the total solid content component, and the resin having a glass transition point of -10 ° C or lower is 6 to 1 of the total solid content component.
5% by weight, and 0.5 to 1 of the total solid content of the fibrous substance.
A step of preparing a joint treatment agent containing weight%. ◎ The process of filling the joint between the gypsum boards with the joint treatment agent.

The joint treatment method according to a fourth aspect of the present invention further comprises the step of arranging a finish putty on the groove portion filled with the joint treatment agent to smooth the groove portion in the second or third aspect of the invention. Contains. The gypsum board assembly according to the fifth aspect of the invention includes a plurality of gypsum boards arranged in a plane and joints formed between the gypsum boards. The joint portion is made of hemihydrate gypsum in an amount of 10 to 93% by weight of the total solid content, and a resin having a glass transition point of -10 ° C or lower in an amount of 6-1 of the total solid content.
5% by weight, and 0.5 to 1 of the total solid content of the fibrous substance.
It is composed of a joint treatment agent which is contained by weight.

A gypsum board aggregate according to a sixth aspect of the present invention is the gypsum board aggregate according to the fifth aspect of the present invention, further including a smooth layer formed by finishing putty disposed on the joint portion. ＊＊＊＊＊＊＊ Joint treatment composition Hemihydrate gypsum used in the present invention is CaSO ₄ · 1 / 2H.
It is an α-type or β-type hemihydrate gypsum represented by ₂ O. When mixed with water, this hemihydrate gypsum undergoes a hydration reaction to become dihydrate gypsum (CaSO ₄ .2H ₂ O). As described above, gypsum dihydrate derived from hemihydrate gypsum is fine needle-like crystals, and these crystals intersect with each other to show an apparent swelling property, and prevent thinning of joints.

The resin contained in the composition of the present invention is for imparting elasticity to the joints and making cracks less likely to occur in the joints. In the present invention, the glass transition point is -1.
A resin having a temperature of 0 ° C or lower, preferably -20 ° C or lower is used. When the glass transition point is higher than −10 ° C., the flexibility of the joints is lowered, and it becomes difficult to effectively prevent the occurrence of cracks in the joints. The type of resin used in the present invention is not particularly limited, and examples thereof include acrylic resin, vinyl acetate-acrylic resin or styrene-
It is preferable to use an acrylic resin.

The above resin component, as the resin itself,
Alternatively, it is used as an emulsion in the composition of the present invention. When using resin emulsion, the solid content is 50%
A high solid emulsion of 60% or more is preferable. The fibrous substance contained in the composition of the present invention is a component for preventing thinning of joints by utilizing its void property. As the fibrous substance, a substance having a length that does not easily get entangled and easily dispersed uniformly in the composition is used. Specifically, the length is 3 mm or less, preferably 1
A fibrous substance having a size of mm or less is preferable. Specific examples of the fibrous substance include natural organic fibers such as pulp, wool, hemp, cotton and silk, synthetic fibers such as acrylic fibers and polyester fibers, and inorganic fibers such as carbon fibers, glass fibers, rock wool and ceramic fibers. It can be illustrated. In addition, two or more kinds of these fibrous substances may be used in combination.

The composition of the present invention may contain a filler, a solvent, a viscosity modifier, and various additives in addition to the above-mentioned essential components. The addition of the filler can lower the fluidity of the composition and can prolong the setting time, so that the workability of the joint treatment is improved. Also, the joint strength is improved. The average particle size of the filler is 250μ
It is preferable to use those of m or less. Average particle size is 250
When a filler having a size of more than μm is used, poor finish of the joint-treated surface may occur. Specific examples of the filler are as follows, for example. Fillers having an average particle size of 100 to 250 μm: hollow ceramic fillers, silica balloons, inorganic foams of granular expanded silica, pebbles, perlite, fine silica sand, fine silica powder, and the like. Fillers having an average particle size of 100 μm or less: titanium dioxide, clay, calcium carbonate, etc.

As the filler, in addition to the above examples, general fine aggregate, extender pigment or coloring pigment can be used. Two or more kinds of the above-mentioned fillers may be mixed and used. For example, fillers having various average particle diameters can be mixed and used. In this case, a preferable combination is 50 fillers having an average particle size of 100 to 250 μm.
˜85% by weight and 15 to 50% by weight of filler having an average particle size of 100 μm or less. The average particle size is 1
A filler component having an average particle size of 10 μm or less (for example, titanium dioxide or clay) has a filler component of 00 μm or less.
It is more preferable to mix the filler in an amount of ˜33 wt% and an average particle size of 10 to 100 μm (eg, calcium carbonate) in an amount of 67 to 80 wt%.

The set retarder is a component for delaying the setting time of the gypsum and adjusting the setting time in order to improve the difficulty of the joint treatment work due to the short setting time of the hemihydrate gypsum. is there. Specific examples of the setting retarder include sodium citrate and starch. The solvent is a component for adjusting the fluidity of the composition of the present invention. Specific examples of the solvent include water, dibutyl phthalate (DBP), and butyl cellosolve. DBP functions as a film-forming auxiliary agent for emulsion. Water is added to make the composition a paste.

The viscosity adjusting agent is for improving workability by adjusting the viscosity of the composition of the present invention.
Examples of the viscosity modifier include hydroxyethyl cellulose and acrylic thickeners. As the additive, various additives used in general water-based paints are used. Specifically, common dispersants for fillers, defoamers, preservatives,
A fungicide or the like is used.

Next, the blending ratio of various components constituting the composition of the present invention will be described. Hemihydrate gypsum is 10 to 93% by weight, preferably 30 to 93% by weight, more preferably 40 to 60% by weight based on the total solid components contained in the composition of the present invention.
Adjust to% by weight. When the proportion of hemihydrate gypsum is less than 10% by weight, the joint becomes thicker and the joint is less smooth. On the other hand, if it exceeds 93% by weight, the elasticity of the joints is reduced and cracks are likely to occur.

The resin having a glass transition point of −10 ° C. or lower is adjusted to 6 to 15% by weight, preferably 9 to 13% by weight, based on the total solid components contained in the composition. When the proportion of the resin component is less than 6% by weight, the joint portion has insufficient elasticity and cracks are likely to occur. On the other hand, when it exceeds 15% by weight, the joint portion becomes thin, and the smoothness of the joint portion deteriorates.

The fibrous substance is 0.5 to 1.0% by weight, preferably 0.7 to 1.0% by weight based on the total solid components contained in the composition.
Adjust to 0.9% by weight. When the amount added is less than 0.5% by weight, the joint portion becomes thin and the joint portion becomes less smooth. On the other hand, if it exceeds 1.0% by weight, the elasticity of the joints is lowered and cracks are likely to occur. When the above-mentioned filler is added to the composition of the present invention, the addition amount of PVC (pigment volume content) represented by the following formula (1) is 65 to 86%, preferably 75 to
It is adjusted to 86%, more preferably 80 to 86%.

[0018]

[Equation 1]

If PVC is less than 65%, the meat of the joint is
The skin becomes thicker and the smoothness of the joints decreases. vice versa,
If the PVC exceeds 86%, the stretchability of the joint will decrease.
Cracks are likely to occur. When adding a retarder
In that case, the amount added should be adjusted appropriately according to the work environment and conditions.
Preferably. Generally, for the amount of hemihydrate gypsum
It is preferable to mix 0.1 to 0.3% by weight. The amount added
If less than 0.1% by weight, add a curing retarder
The effect of the composition is small, and the composition cures too quickly to improve workability.
descend. On the contrary, if it exceeds 0.3% by weight, curing will be slow.
It becomes too much, and the meat in the joint area becomes thin. Gypsum board aggregate With reference to FIGS. 1 and 2, the joint treatment for the gypsum boat described above.
Gypsum board aggregates with joints formed using the composition
explain about. In the figure, the gypsum board aggregate 10
Is three rectangular gypsum boards 10 arranged in the width direction.
a, 10b, 10c and each gypsum boat 10a, 10b,
The joint part 11 formed between 10c and the gypsum board 10a,
Mainly composed of the cross 12 arranged on 10b and 10c.
Is made. Such a gypsum board aggregate 10 is
Inside the building so that the surface on which the loss 12 is placed is on the indoor side
Used as a wall material.

Each gypsum board 10a, 10b, 10c is
For example, a gypsum boat specified in JIS-A6901,
Examples thereof include a heat-insulating gypsum board or a panel board, a waterproof gypsum board specified by A6912, a gypsum lath board specified by A6906, a sound absorbing gypsum board specified by A6301 or a reinforced gypsum board specified by A6913.

The joint portion 11 is a gypsum boat 10a, 10b.
And V-shaped groove 1 formed at the joint between 10b and 10c
3 (see FIG. 2). Also, the joint portion 11
Is formed of the above-described joint treatment composition for gypsum board. Since the joint portion 11 is made of the above composition, the joint portion 11 has a simpler structure than the conventional example. Moreover, it does not tend to cause skin thinning or cracking.

The cloth 12 is, for example, paper, vinyl or cloth cloth. FIG. 3 is a diagram corresponding to FIG. 2 of another example. In this example, the finish putty layer 14 is arranged on the joint portion 11, and the surface smoothness of the joint portion 11 is further enhanced. Further, instead of the cloth 12, a coating film 15 made of an interior paint is formed on the gypsum boards 10a, 10b, 10c.

In this example, since the finish putty layer 14 enhances the surface smoothness of the joint portion 11, the appearance of the coating film 15 such as a step is unlikely to occur. As the finishing putty for forming the finishing putty layer 14, vinyl acetate emulsion-based putty, Veova emulsion-based putty, synthetic resin emulsion-based putty, or the like is used. Method for Forming Gypsum Boat Assembly Next, the method for forming the gypsum board aggregate 10 will be described while referring to the joint treatment method using the joint treatment composition for gypsum board.

First, the gypsum board 10 on the inner wall surface of the building
The a, 10b, and 10c are arranged and fixed in the width direction. As a fixing method, a general fixing method of gypsum board is adopted. Next, the groove 13 formed in the joint portion of the gypsum boards 10a, 10b, 10c is filled with the joint treatment agent made of the above composition.

Here, as the joint treatment agent composed of the above composition, a first agent containing a resin having a glass transition point of -10 ° C. or less and a fibrous substance, and a second agent containing hemihydrate gypsum are prepared. However, it is preferable to adjust by mixing the first agent and the second agent so that the hemihydrate gypsum, the resin and the fibrous substance are contained in the above-mentioned proportions. This is because if the resin, fibrous substance and hemihydrate gypsum are mixed from the beginning, the composition will harden before the work, making the work difficult. When the composition contains components other than the essential components of hemihydrate gypsum, resin and fibrous substance (for example, filler), it is preferable to include the curing retarder in the second agent and the other components in the first agent.

The joint treatment agent prepared by mixing the first agent and the second agent as described above is filled in the groove 13 with a spatula or a metal iron, and hardens if left for a predetermined time. As a result, the joint portion 11 is formed. The surface of the formed joint 11 is finished by polishing.
Finally, the cloth 12 is pasted on the gypsum boards 10a, 10b, 10c to complete the gypsum boat aggregate 10 described above.

When the coating film 15 is formed instead of the cloth 12, the finished putty layer 14 is formed on the joint portion 11, and the surface of the finished putty layer 14 is polished smoothly. When the interior coating material is applied thereafter to form the coating film 15, the appearance of the coating film 15 is unlikely to have a step. According to the joint treatment method for gypsum board as described above, the joint treatment agent described above is used for the groove 13
Since the joint treatment is completed just by filling the joint with the above, the work is remarkably simplified and the work cost is reduced as compared with the conventional joint treatment method.

[0028]

EXAMPLES Examples 1 to 3 and Comparative Examples 1 to 7 For each of the Examples and Comparative Examples, a first agent and a second agent were prepared as shown in Tables 1 to 10 below.

[0029]

[Table 1]

[0030]

[Table 2]

[0031]

[Table 3]

[0032]

[Table 4]

[0033]

[Table 5]

[0034]

[Table 6]

[0035]

[Table 7]

[0036]

[Table 8]

[0037]

[Table 9]

[0038]

[Table 10]

Next, the first agent and the second agent were mixed to form a paste, and this paste was filled in a groove portion (75 mm in length) formed in the abutting portion of a gypsum board (bevel board) using a spatula. . Two samples were prepared for each of the examples and comparative examples, and the following experiments were carried out using the samples as samples.
The results are shown in Table 11. Leaning test After the sample was left for 24 hours, the joints were visually observed.
The evaluation criteria are as follows.

⊚: No lean meat. ○: Very little meat loss. X: The meat is significantly thin. Crack Generation Test After allowing the sample to stand for 7 days, the sample was repeatedly stretched by a fatigue tester, and the number of times of stretching and the state of occurrence of cracks and fractures were examined.

The test conditions by the tester were such that the expansion / contraction width was set to 0.5 mm and the repetition rate was set to 20 times / minute. Comparative Example 8 Joints were formed using a commercially available joint putty (IP Putty Universal made by International Paint Co., Ltd.), and the same test was performed. The results are shown in Table 11.

[0042]

[Table 11]

[0043]

The joint treatment composition for gypsum board according to the first aspect of the present invention contains hemihydrate gypsum, a resin having a glass transition point of -10 ° C or less, and a fibrous substance in the above-mentioned proportions, so that the skin becomes thin or cracked. It is possible to easily form joints that are unlikely to occur. Second,
According to the third and fourth aspects, since the joint treatment composition for gypsum board according to the first aspect is used, it is possible to easily form joints which are less likely to cause skin thinning and cracks.

Since the plasterboard aggregates according to the fifth and sixth inventions use the joint treatment composition for gypsum board according to the first invention, the structure of the joints is simplified and the joints are Is less likely to crack or lose weight.

[Brief description of drawings]

FIG. 1 is a front view of a plasterboard aggregate according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along line II-II of FIG.

FIG. 3 is a diagram corresponding to FIG. 2 of another example.

FIG. 4 is a schematic vertical sectional view of a joint portion of a conventional example.

[Explanation of symbols]

 10 Gypsum board aggregate 10a, 10b, 10c Gypsum board 11 Joint part 14 Finishing putty layer

Claims (6)

[Claims] 1. Hemihydrate gypsum is used in an amount of 10 to 93% by weight based on the total solid content, and a resin having a glass transition point of -10 ° C. or lower is added to the total solid content of 6%.
A joint treatment composition for gypsum board containing ˜15% by weight and 0.5 to 1% by weight of the total solid content of the fibrous substance. 2. A joint treatment method for forming joints in grooves formed between gypsum boards, wherein a first agent containing a resin having a glass transition point of −10 ° C. or lower and a fibrous substance is prepared. A step of preparing a second agent containing hemihydrate gypsum, the hemihydrate gypsum is 10 to 93% by weight of the total solid content component, the resin is 6 to 15% by weight of the total solid content component, the fibrous A step of mixing the first agent and the second agent so that the substance is contained in a proportion of 0.5 to 1% by weight of the total solid content component to prepare a joint treatment agent; and the joint treatment agent in the groove. And a joint treatment method including the step of filling. 3. A joint treatment method for forming joints in grooves formed between gypsum boards, wherein hemihydrate gypsum is 10 to 93% by weight of all solid components and the glass transition point is -10 ° C. or lower. Preparing a joint treatment agent containing 6 to 15% by weight of the resin as a solid component and 0.5 to 1% by weight of a fibrous substance as a solid component, and filling the groove portion with the joint treatment agent. And a joint treatment method including the step of: 4. The joint treatment method according to claim 2, further comprising the step of disposing a finish putty on the groove portion filled with the joint treatment agent to smooth the groove portion. 5. A plurality of gypsum boards arranged in a plane, hemihydrate gypsum in an amount of 10 to 93% by weight of the total solid content, and a resin having a glass transition point of -10 ° C. or lower in an amount of 6 to 6 of the total solid content. A gypsum board aggregate having a joint portion formed between the gypsum boards, which comprises a joint treatment agent containing 15% by weight and 0.5 to 1% by weight of the total solid content of the fibrous substance. 6. The gypsum board aggregate according to claim 5, further comprising a smooth layer made of a finished putty disposed on the joint portion.