JPS6055656B2 - Sealing method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of sealing joints in buildings using a silicone sealant, and more particularly, to a method of sealing without causing staining around the joints.

Polyorganosiloxane compositions that harden at room temperature to become rubber-like elastic bodies have excellent heat resistance and weather resistance, little change in physical properties due to temperature, and less deterioration due to ozone and ultraviolet rays, so they are used in construction. Widely used as a sealant.

Although such silicone elastomers have the excellent properties mentioned above, even after curing, polyorganosiloxane that does not participate in crosslinking remains, and its leaching causes staining around the joints. It has the disadvantage of

In other words, the area around the joint where the polyorganosiloxane has oozed out and diffused tends to attract dust, and since the polyorganosiloxane covers the attached dust and makes the dust water repellent, the dust is not washed away by rainwater, and the area around the joint The staining progresses and the aesthetic appearance is noticeably impaired. Previously, the present inventors developed a polyorganosiloxane consisting of SiO2 units and RASiOll2 units and having a silanol group bonded to a silicon atom, a silanol group end-capped polydiorganosiloxane, and an organoaminoxy group bonded to a silicon atom. A polysiloxane film is formed on the sealant surface by dissolving the silicone compound in volatile organosiloxane and an organic solvent and applying the solution to the silicone sealant surface and curing it. We discovered a method to prevent polysiloxane from seeping out and spreading around the joints and applied for a patent (patent application filed in 1983).
784, see specification).

Although this method significantly reduced the amount of contamination,
It wasn't perfect yet. Therefore, the inventors of the present invention further studied methods for suppressing the occurrence of staining as much as possible, and as a result, completed the present invention. That is, the present invention comprises: (4) 10 parts by weight of a polydiorganosiloxane whose ends are blocked with silanol groups and whose viscosity at 25°C is 100 to 200,000 ISt; (B) an average of 2 parts per molecule;
(C) 5 to 30 parts of an inorganic filler, and (2) a carbon-carbon triple bond. A silicone sealant containing 0.01 to 1 part of a monohydric unsaturated alcohol having a hydroxyl group bonded to a primary or secondary carbon atom is filled into the joints of a building. The present invention relates to a method for sealing joints in buildings, which is characterized by applying (E) (meth)acrylic ester emulsion paint to the surface of the joints.

The surface of the building joint sealed by the method of the present invention is coated with a (meth)acrylic ester resin film that is highly effective in preventing leaching of polyorganosiloxane. There is almost no leaching of polyorganosiloxane from the inside to the area around the joint.

Furthermore, since the (meth)acrylic ester resin paint adheres well to the silicone sealant used in the present invention, there is no concern that the (meth)acrylic ester resin film will peel off from the surface of the sealant. ) The acrylic ester resin film can prevent polysiloxane from seeping out from the silicone sealant over a long period of time, thereby preventing staining around the joints. Component (4) used in the present invention is the same as the silanol-terminated polydiorganosiloxane that is commonly used in condensed polysiloxane compositions that can be cured at room temperature, and particularly provides appropriate workability to the composition. In addition, the viscosity at 25°C is 100 to 200,000'S in order to provide suitable physical properties for use as an architectural sealant.
It is necessary that the value be within the range of t.

The viscosity is 10ck1. If the temperature is less than 200,000C, the physical properties required as a building sealant cannot be obtained.
If it exceeds st, a uniform sealing material cannot be obtained and the extrusion workability also deteriorates. A particularly preferable range is 500 to 50,000C in terms of harmonizing both properties.
It is st. Examples of organic groups directly bonded to silicon atoms include alkyl groups such as methyl, ethyl, propyl, butyl, and hexyl; alkenyl groups such as vinyl and allyl; aryl groups such as phenyl; β−
aralkyl groups such as phenylethyl, and 3,3,
Examples include monovalent substituted hydrocarbon groups such as 3-trifluoropropyl group, chloromethyl group, and β-cyanoel group; In general, methyl groups are advantageous; among them, methyl groups not only provide the easiest raw material intermediate, but also provide the lowest viscosity relative to the degree of polymerization of the siloxane, improving extrusion workability and physical properties of the sealant. In order to improve the balance, it is preferable that 85% or more of all organic groups be methyl groups, and it is more preferable that substantially all organic groups be methyl groups.

However, when cold resistance or heat resistance is required, it is recommended to use phenyl groups as part of the organic groups. The aminoxy group-containing organosilicon compound of component (B) used in the present invention is capable of crosslinking and chain length of the polysiloxane by carrying out a dehydroxylamine reaction with the terminal silanol group of component (4). It extends, and may be a silane derivative or a chain, cyclic or branched siloxane derivative.

For the purpose of obtaining a sealing material with particularly good reactivity and high elongation, a combination of cyclic polysiloxanes having two and three aminoxy groups in one molecule is preferred. The organic groups to be combined with the aminoxy group include two monovalent hydrocarbon groups such as methyl, ethyl, propyl, butyl, and cyclohexyl groups, or two monovalent hydrocarbon groups such as butylene and pentene groups.
One example is a valent hydrocarbon group, but an ethyl group is preferred from the viewpoint of easy availability of raw materials, ease of synthesis, reactivity, and ease of volatilization of organohydroxylamine to be released. . Examples of such aminoxy group-containing organosilicon compounds include the following. Hereinafter, for the sake of simplicity, the following abbreviations will be used for each organosilicon compound. (Abbreviation) Me: methyl group, Et: ethyl group, Bu: butyl group, V
i: vinyl group, Ph: phenyl group The amount of such aminoxy group-containing organosilicon compound added is (4) component 100
0.1 to 30 parts by weight, preferably 1 to 1 part by weight
5 parts by weight.

If the amount of the aminoxy group-containing organosilicon compound added is less than 0.1 part by weight, the reaction rate with the silanol-terminated polydiorganosiloxane will become too fast and sufficient working time will not be obtained, and the amount added will be less than 3 parts by weight. If it exceeds this, the rubber elasticity of the sealant decreases. Used in the present invention (
Component C) is used as a base material to give the sealant appropriate fluidity or non-flowability depending on the purpose and processing conditions, and to give it the mechanical strength and hardness necessary as a sealant for construction. Examples include fumed silica, precipitated silica, silica aerogel, ground silica, diatomaceous earth, iron oxide, titanium oxide, calcium carbonate, etc., and are preferably inorganic fine powders.

In particular, it is preferable to use calcium carbonate because it is easy to obtain a sealant with a high elongation rate in the rubber-like cured part.
These inorganic fillers may be used alone or in combination of two or more. The amount of such inorganic filler added is 5 to 30 parts by weight, preferably 3 parts by weight per 10 parts by weight of the prisoner component.
The range is 0 to 20 parts.

This is because if component (C) is less than this, it will not be able to provide the required physical properties to the sealant, and if it is too much, workability will decrease.Also, the amount used as a coloring agent Pigments such as titanium oxide, cobalt oxide, red iron oxide, carbon black, and phthalocyanine pigments may be added.

Component (D) used in the present invention is a component for imparting adhesion ability of (meth)acrylic ester resin paint to the sealant, and is made from a monovalent unsaturated alcohol containing a carbon-carbon triple bond l. To be elected.

These unsaturated alcohols must have their alcoholic hydroxyl group bonded to a primary or secondary carbon atom, and those with a hydroxyl group on a tertiary carbon atom (
Since the non-adhesive ability of meth)acrylic ester resin paints cannot be obtained, application to the present invention is inappropriate. The same applies to polyhydric alcohols. Furthermore, these tertiary alcohols,
It is acceptable that polyhydric alcohol is contained as an impurity in component (D).

The above (D) component has the general formula 81-C=C-R2-0
H [R1 is a hydrogen atom or a monovalent hydrocarbon group, R2 is 2
Unsaturated alcohols represented by [hydrocarbon group] are preferred, and the following are exemplified.

The amount of component (D) added is 0.00 parts by weight per 100 parts by weight of the compound.
It is preferable to use it in the range of 0.01 to 1 part
．． It is more preferable to use it in a range of 0.05 to 5 parts by weight. (2) Even if the amount of the component is less than 0.01 part by weight or more than 1 part by weight, the adhesion ability of the (meth)acrylic ester resin paint will decrease. (E) (meth)acrylic ester emulsion paint is (4) to (D)
A (meth)acrylic ester-based resin film is formed by coating the surface of a sealant consisting of the following ingredients, and the resin film prevents polysiloxane that does not undergo crosslinking from seeping out and diffusing from inside the sealant to the area around the joint. This is to prevent the occurrence of contamination. These can be selected from homopolymer emulsions and copolymer emulsions of acrylic esters and methacrylic esters, and copolymer emulsions of vinyl acetate, styrene, acrylonitrile, acrylamide, acrylic acid, etc., and are flexible after curing. Preferred is an elastic paint that forms a comb-like elastic film.Such a (meth)acrylic ester-based elastic paint has excellent adhesion to the silicone sealant consisting of components (4) to (2), and has flexibility. Because of this, it is able to follow the movement of joints, has excellent weather resistance, and is also effective in preventing the leaching of polyorganosiloxane that does not participate in crosslinking as described above.
It is most effective in preventing polysiloxane from oozing out from the silicone sealant over a long period of time and preventing staining of the areas around the joints. These (meth)acrylic ester emulsion paints are applied to the surface of the silicone sealant made of components (4) to (D) using a brush, spatula, roller, etc. after the silicone sealant is placed. The present invention is suitable as a method for sealing joints in buildings using wall materials that are prone to staining, such as stone materials such as stone and marble, tiles, and enamel. The present invention will be explained below with reference to Examples.

In the Reference Examples and Examples, all parts indicate parts by weight. Reference Example 1 100 parts of polydimethylsiloxane with a viscosity of 3,000 cSt at 25°C and whose ends are blocked with silanol groups are mixed with 65 parts of rosin acid-treated colloidal calcium carbonate having an average particle size of 0.6μ in a kneader to make a base. I got the compound.

This base compound is 10Ci! For I), AMe
BuSiOA. IMeX? 195% by weight and LI-M
eBuSiO+4MeSi0+-! 3.5 parts of a crosslinking agent mixture consisting of 5% by weight and the unsaturated alcohol shown in Table 1 were added and mixed to form silicone sealants S-1~
S-3 was obtained.

Note that the sealing material S-1 is a comparative example in which unsaturated alcohol is not added. Reference Example 2 100 parts of polydimethylsiloxane with a viscosity of 5,000 CSt at 25°C and end-capped with silanol groups was added with heavy calcium carbonate 5-chloride having an average particle size of 1 μm and a stearic acid-treated light product having an average particle size of 0.2 μm. A base compound was obtained by mixing 5 parts of calcium carbonate in a kneader.

l+Me2 for 1 (1) part of this base compound
94% by weight of JMeSiO on SiO and LEMe2Si
O+]MeSiO. Sealing materials S-4 to S-6 were obtained by adding and mixing 3.0 parts of a crosslinking agent mixture consisting of 6 wt. Sealing material S-4 is a comparative example in which unsaturated alcohol is not added. Example 1 As shown in Figure 1, length 30 cm, width 2
Between two white ceramic tiles 3 of 0 cm and 15 irises thick,
Test specimens 10 to 17 were prepared by pouring the sealing materials S-1 to S-3, 1 prepared in Reference Example 1.

After curing these test specimens at room temperature for 3 days, a (meth)acrylic ester emulsion paint 2 shown in Table 3 was applied to the surface of the sealant 1 and exposed outdoors. 1 month, 3 months, 6 months, and 12 months after exposure. The degree of staining on the tile surface was read using the Munsell value. The results are also shown in Table 3. Note that the sealing material S-1 used for test specimens 10 and 11 did not have paint adhesion ability, and test specimen 10 was not coated with paint. In addition, the coating film of test specimen 11 had already peeled off after the third month of outdoor exposure. Example 2 Length 50C! Between two Mikage stones (type: Inada, finish: burner finish) with a width of 15c7n and a thickness of 25cm.
The sealing materials S-4 to S-6 prepared in Reference Example 2 were cast to prepare test specimens 20 to 25 having the same joint dimensions as shown in FIG. 1.

After curing these test specimens at room temperature for 3 days, an acrylic ester emulsion paint shown in Table 4 was applied to the surface of the sealant and exposed outdoors. One month, three months, and six months after the exposure, water was sprinkled on the surface of Mikageite and the presence or absence of water was observed. The results are also shown in Table 4. It should be noted that the sealing material S-4 used for the test piece 2 suction 21 had no paint adhesion ability, and no paint was applied to the test piece 20.

In addition, the coating film of test specimen 21 had already peeled off after the first month of outdoor exposure. Example 3 As shown in FIG. 2, the sealant S prepared in Reference Example 1 was placed between two pieces of mortar 5.
Test specimens were prepared by pouring the sealing materials S-5 and S-4 prepared in Example 2 and Reference Example 2.

After curing these test specimens at room temperature for 3 days, paint 6 shown in Table 5 was applied to the surface of sealant 4 and dried and hardened. Next, the test specimen was placed in a weatherometer so that the painted surface was irradiated with ultraviolet light. UV irradiation 2
After 00 hours, the test specimen was repeatedly attached to a fatigue testing machine, a ±10% displacement of 2,00 (2) was applied, and the presence or absence of abnormalities in the coating film was observed. The results are also shown in Table 5. *4 Vinyl chloride-based product name manufactured by Dainippon Toyo Co., Ltd. *5 Acrylic enamel-based product name manufactured by Kansai Paint Co., Ltd. *6 Epoxy-based product name manufactured by Shinto Paint Co., Ltd. *7 Acrylic urethane Example 4 (Product name manufactured by Dainippon Toyo Co., Ltd.) Example 4 Alcohol-backed burner finish Reference example 1 was used as a sealant at the joints of a building (width 12wn 1 depth 9Wgfi) whose exterior wall material was Mikage stone (type: portillon). S-
2 was turned, and Aroncoat ST was further applied to the surface thereof.

Six months have passed since the turning, but there is still water repellency around the joint.
No stains or other contamination was observed. Example 5 Joints of a building using white enamel board as exterior wall material (width 15 pieces,
At a depth of 1-), S-2 of Reference Example 1 was lathed as a sealing material, and Aroncoat ST was further applied to the surface.

Eleven months have passed since turning, but no staining was observed around the joints.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of the outdoor exposure test specimen used in Example 1, and FIG. 2 is a perspective view of the cyclic fatigue test specimen used in Example 3. In addition, the numerical values other than the following in the figure indicate dimensions, and the units are ugly. 1...Sealing material, 2...
Paint film, 3... Unglazed tile, 4...
Sealing material, 5...Mortar, 6...
·paint.

Claims (1)

[Scope of Claims] 1 (A) 100 parts by weight of a polydiorganosiloxane whose ends are blocked with silanol groups and whose viscosity at 25°C is 100 to 200,000 cSt; (B) an average of 2
0.1 to 30 parts by weight of an aminoxy group-containing organosilicon compound having more than 100 organoaminoxy groups, (C)
5 to 300 parts by weight of an inorganic filler, and (D) 0.01 to 0.01 to 300 parts by weight of a monovalent unsaturated alcohol having a carbon-carbon triple bond and a hydroxyl group bonded to a primary or secondary carbon atom.
After filling the joints of a building with a silicone sealant containing 10 parts by weight, (E) (meta) is applied to the surface of the joint.
A method of sealing joints in buildings, characterized by applying an acrylic ester emulsion paint. 2(A) has a viscosity of 500 to 50,000 at 25°C
The sealing method according to claim 1, wherein the sealing method is cSt. 3. The sealing method according to claim 1, wherein 85% or more of the organic groups in (A) are methyl groups. 4. The sealing method according to claim 3, wherein all of the organic groups in (A) are methyl groups. The sealing method according to claim 1, wherein the organoaminoxy group in 5(B) is a diethylaminoxy group. 6. The sealing method according to claim 1, wherein the inorganic filler (C) is calcium carbonate. 7(D) has the general formula R^1-C≡C-R^2-OH(R^
The sealing method according to claim 1, wherein 1 is a hydrogen atom or a monovalent hydrocarbon group, and R^2 is an unsaturated alcohol represented by a divalent hydrocarbon group. The sealing method according to claim 1, wherein the amount of 8(D) added is 0.05 to 5 parts by weight. 9. The sealing method according to claim 1, wherein the (meth)acrylic ester emulsion paint of 9(E) is an elastic paint.