JP4899372B2 - Silicone sealant coating material and its construction method - Google Patents

Description

  The present invention relates to a coating material for a silicone-based sealing material and a construction method thereof.

Conventionally, when an outer wall material is constructed, a sealing material has been used as a material for filling joints and gaps between members (generally called joints) to make the joints watertight and airtight. There are various kinds of sealants, and silicone sealants excellent in water resistance, durability, weather resistance, etc. are widely used.
However, when the silicone sealant is filled in the joint, the low molecular weight compound in the silicone sealant elutes and covers the surface of the outer wall material, and further pollutants in the atmosphere adhere to the outer wall surface. There is a problem that the appearance is significantly contaminated.

In order to solve such a problem, a technique has been proposed that aims to realize resistance to contamination by an elution component from a silicone sealant (see, for example, Patent Document 1). Patent Document 1 states that “a first coating layer having permeability in the film thickness direction with respect to the organosilicone low molecular weight compound is formed on the surface of the base material, and a coating film is formed on the first coating layer. Describes an exterior material characterized in that a second coating layer made of a silicone coating material containing an optical semiconductor and having a hydrophilic contact angle with water of 40 ° or less is formed.
In addition, a silicone coating material applied to the surface of a silicone sealing material is known.

JP 2004-223958 A

However, since the exterior material described in Patent Document 1 is provided with a coating layer on the surface of the outer wall material, the cost is higher than that of the conventional outer wall material, and when used for large buildings such as buildings. The difference is quite large. Moreover, the contamination by the elution component from the silicone sealant could not be sufficiently prevented.
Further, conventionally known coating materials (for example, Hamatite VY-52 manufactured by Yokohama Rubber Co., Ltd.) cannot sufficiently prevent the low-molecular silicone oil from flowing out from the silicone-based sealing material, and thus the contamination prevention effect is not sufficient. In addition, when used on joints with movement such as a panel method, deterioration with time is promoted to cause cracks and the like, which may lead to a reduction in pollution prevention effect.

  Therefore, an object of the present invention is to provide a coating material for a silicone-based sealing material that can sufficiently prevent contamination due to an elution component from the silicone-based sealing material over a long period of time.

  As a result of intensive studies, the present inventor applied a composition containing a hydrolyzable silyl group-containing polyisobutylene polymer, an organotin compound, and a solvent to the surface of the silicone sealant. From the silicone sealant, As a result, it was found that the contamination by the eluted components can be sufficiently prevented over a long period of time, and the present invention has been completed.

That is, the present invention provides the following (1) to (6).
(1) A coating material for a silicone sealant containing a hydrolyzable silyl group-containing polyisobutylene polymer (A), an organotin compound (B), and a solvent (C).
(2) The coating material for a silicone-based sealing material according to (1), wherein the organotin compound (B) is a tetravalent organotin compound.
(3) The coating material for a silicone-based sealing material according to (1) or (2), wherein the organotin compound (B) is contained in an amount of 0.5 to 10 parts by mass with respect to 100 parts by mass of the polymer (A). .
(4) The coating material for a silicone-based sealing material according to any one of (1) to (3), further containing an amine (D).
(5) The construction method of the coating material for silicone type sealing materials which apply | coats the coating material for silicone type sealing materials in any one of said (1)-(4) to the surface of the hardened silicone type sealing material.
(6) The construction method of the coating material for silicone type sealing materials which apply | coats the coating material for silicone type sealing materials in any one of said (1)-(4) to the surface of an uncured silicone type sealing material.

  The coating material for a silicone-based sealant of the present invention can sufficiently prevent contamination due to an elution component from the silicone-based sealant over a long period of time.

Hereinafter, the present invention will be described in more detail.
The coating material for a silicone-based sealing material of the present invention (hereinafter also referred to as “the coating material of the present invention”) includes a hydrolyzable silyl group-containing polyisobutylene polymer (A), an organotin compound (B), a solvent ( C).
In the present specification, the silicone sealant means a sealant mainly composed of silicone (organopolysiloxane).

<Polymer (A)>
The polymer (A) used in the coating material of the present invention is a hydrolyzable silyl group-containing polyisobutylene polymer. Specifically, for example, a polyisobutylene polymer having a silyl group represented by the following formula (1) at the terminal may be mentioned.

In formula (1), R ¹ , R ² and R ³ are each independently a hydrolyzable group, and are a hydrogen atom, an alkoxy group, an acyloxy group, a ketoximate group, an amino group, an amide group, an aminooxy group, a mercapto group. Group is preferably an alkenyloxy group. In particular, an alkoxy group is more preferable, and a methoxy group and an ethoxy group are more preferable in terms of mild hydrolyzability and easy handling.

  The number average molecular weight of the polymer (A) is preferably from 300 to 30,000, more preferably from 5,000 to 10,000, from the viewpoints of solubility and adhesiveness.

  The polymer (A) can be produced by a known method. Moreover, you may use a commercial item. Specific examples include EPION (E100S, E103S, E303S, E505S) manufactured by Kaneka Corporation.

<Organic tin compound (B)>
The organotin compound (B) used for this invention is not specifically limited, The organotin compound generally used as a silanol condensation catalyst can be used. Specific examples include dialkyltin oxide, dialkyltin dialkoxide, and dialkyltin carboxylate.
Examples of the dialkyltin oxide include dibutyltin oxide and dioctyltin oxide.
Examples of the dialkyl tin dialkoxide include dibutyl tin dimethoxide.
Examples of the dialkyltin carboxylate include dibutyltin diacetate, dibutyltin maleate, dibutyltin dioctanoate, dibutyltin dilaurate, and dioctyltin laurate.
These may be used alone or in combination of two or more.
Among these, tetravalent organotin compounds are preferable from the viewpoint of excellent storage stability and curability. In particular, dibutyltin dilaurate is more preferable.

  The content of the organotin compound (B) is preferably 0.5 to 10 parts by mass with respect to 100 parts by mass of the polymer (A) from the viewpoint of excellent storage stability and curability. More preferably, it is part by mass.

<Solvent (C)>
The solvent (C) used for this invention will not be specifically limited if it is inactive with respect to the said component and has moderate volatility.
Specific examples of the solvent (C) include methyl ethyl ketone, dimethylacetamide, acetone, ethyl acetate, butyl acetate, cellosolve acetate, mineral spirit, toluene, xylene, n-hexane, isohexane, methylene chloride, tetrahydrofuran, and ethyl. Examples include ether and dioxane.
These may be used alone or in combination of two or more. Of these, n-hexane and ethyl acetate are preferable.

  The content of the solvent (C) is 50 to 500 parts by mass with respect to 100 parts by mass of the total solid content in the composition. It is preferable from the point from which a film | membrane is obtained, and it is more preferable that it is 100-200 mass parts.

<Amine (D)>
The coating material of the present invention preferably further contains an amine (D). As the amine (D), a primary amine, a secondary amine, or a tertiary amine can be used, and a primary amine is preferable from the viewpoint of excellent curability.
The primary amine is not particularly limited as long as it is a compound having an amino group (—NH ₂ ). Specifically, for example, laurylamine, metaxylylenediamine (MXDA), 1,3-bisaminomethylcyclohexane (1,3-BAC), norbornanediamine (NBDA), diaminodiphenylmethane, diethylenetriamine, triethylenetetramine, tetra Examples thereof include amine compounds such as ethylenepentamine, diaminodiphenylsulfone, isophoronediamine (IPDA), dicyandiamide, dimethylbenzylamine and ketimine compounds, and polyamines having a polyamide skeleton synthesized from a dimer of linolenic acid and ethylenediamine.
These may be used alone or in combination of two or more.
In particular, a primary amine having 6 to 18 carbon atoms is preferable from the viewpoint of excellent curability. In particular, laurylamine is more preferable.

  As for content of the said amine (D), 0.1-5 mass parts is preferable with respect to 100 mass parts of said polymers (A), and 0.2-1 mass part is more preferable.

  The coating material of the present invention is a filler, a reaction retarding agent, an anti-aging agent, an antioxidant, a pigment (dye), a plasticizer, a thixotropic agent, if necessary, within a range that does not impair the purpose of the present invention. , Ultraviolet absorbers, flame retardants, surfactants (including leveling agents), dispersants, dehydrating agents, adhesion-imparting agents, antistatic agents, and other various additives.

  Examples of the filler include organic or inorganic fillers having various shapes. Specifically, for example, fumed silica, calcined silica, precipitated silica, ground silica, fused silica; diatomaceous earth; iron oxide, zinc oxide, titanium oxide, barium oxide, magnesium oxide; calcium carbonate, magnesium carbonate, zinc carbonate; Waxite clay, kaolin clay, calcined clay; carbon black; these fatty acid treated products, resin acid treated products, urethane compound treated products, and fatty acid ester treated products.

  Specific examples of the reaction retarder include alcohol-based compounds.

Specific examples of the anti-aging agent include hindered phenol compounds.
Specific examples of the antioxidant include butylhydroxytoluene (BHT) and butylhydroxyanisole (BHA).

  Specific examples of the pigment include inorganic pigments such as titanium oxide, zinc oxide, ultramarine, bengara, lithopone, lead, cadmium, iron, cobalt, aluminum, hydrochloride, sulfate, etc .; azo pigment, phthalocyanine pigment, quinacridone Pigment, quinacridone quinone pigment, dioxazine pigment, anthrapyrimidine pigment, ansanthrone pigment, indanthrone pigment, flavanthrone pigment, perylene pigment, perinone pigment, diketopyrrolopyrrole pigment, quinonaphthalone pigment, anthraquinone pigment, thioindigo pigment, benzimidazolone Examples thereof include organic pigments such as pigments, isoindoline pigments, and carbon black.

  Specific examples of the plasticizer include, for example, dioctyl phthalate (DOP), dibutyl phthalate (DBP); dioctyl adipate, isodecyl succinate; diethylene glycol dibenzoate, pentaerythritol ester; butyl oleate, methyl acetylricinoleate; phosphorus Examples include tricresyl acid, trioctyl phosphate; propylene glycol polyester adipate, butylene glycol polyester adipate, and the like.

Specific examples of the thixotropic agent include aerosil (manufactured by Nippon Aerosil Co., Ltd.), disparon (manufactured by Enomoto Kasei Co., Ltd.), and the like.
Specific examples of the adhesion-imparting agent include terpene resins, phenol resins, terpene-phenol resins, rosin resins, xylene resins, and the like.

Specific examples of the flame retardant include chloroalkyl phosphate, dimethyl / methyl phosphonate, bromine / phosphorus compound, ammonium polyphosphate, neopentyl bromide-polyether, brominated polyether, and the like.
Examples of the antistatic agent generally include quaternary ammonium salts; hydrophilic compounds such as polyglycols and ethylene oxide derivatives.

  The method for producing the coating material of the present invention is not particularly limited. For example, each of the above-described essential components and, if necessary, amine (D), other additives, and the like are mixed and heated at room temperature or using a mixing device such as a ball mill. It is obtained by sufficiently kneading and uniformly dispersing under (for example, 40 ° C.).

  When applied to the surface of a silicone sealant, the coating material of the present invention can sufficiently prevent contamination due to the eluted components from the silicone sealant. In addition, since the coating material of the present invention forms a film having excellent toughness, it can sufficiently follow the joint even when used in places with movement such as joints in the panel method, and is excellent in weather resistance, so it can be used for a long time. The anti-contamination effect can be maintained across. Furthermore, since the coating material of the present invention is applied to the surface of the silicone-based sealing material, it can be constructed at a lower cost than using an exterior material in which a coating layer is further provided on the surface of the outer wall material. Any place can be used.

Next, the construction method of the coating material for silicone type sealing materials of this invention is demonstrated.
The first aspect of the method for applying the coating material for a silicone sealant of the present invention (hereinafter referred to as “the method of construction of the present invention”) is the above-described coating material of the present invention on the surface of a cured silicone sealant. It is a construction method of the coating material for silicone type sealing materials which apply | coats.

  The coating material of the present invention is applied to the surface of the cured silicone sealant using a commonly applied coating method such as brush coating, spray coating, wire bar method, blade method, roll coating method, dipping method, etc. Can be applied.

  The first aspect of the construction method of the present invention comprises a step of placing and curing a silicone-based sealing material on the surface of the cured silicone-based sealing material before the step of applying the coating material of the present invention. Is preferred.

  The 2nd aspect of the construction method of this invention is a construction method of the coating material for silicone type sealing materials which apply | coats the coating material of this invention mentioned above to the surface of an uncured silicone type sealing material.

  The coating material of the present invention can be applied to the surface of an uncured silicone sealant using, for example, a spray coating method.

According to the 1st aspect of the construction method of this invention, the contamination by the elution component from a silicone type sealing material can fully be prevented. In addition, the anti-contamination effect can be maintained over a long period of time. Furthermore, it can be constructed relatively cheaply than using an exterior material in which a coating layer is further provided on the surface of the outer wall material, and can be used regardless of the location of the sealing material.
According to the 2nd aspect of the construction method of this invention, the effect similar to the 1st aspect of the construction method of this invention is acquired, and the time which construction requires can be shortened.

Hereinafter, the present invention will be specifically described with reference to examples. However, the present invention is not limited to these.
<Examples 1-3>
Each component of the following Table 1 was mixed with the composition (parts by mass) shown in Table 1 using a stirrer to obtain each coating material shown in Table 1.

<Comparative Example 1 and Comparative Example 2>
The conventional coating material 1 shown in Table 1 (silicone coating material, Hamatite VY52, manufactured by Yokohama Rubber Co., Ltd.) was used as Comparative Example 1, and the conventional coating material 2 (urethane antifouling agent for siding sealants, Auton Protector A, Auto Chemical Industries, Ltd.) was used as Comparative Example 2.

<Dirt evaluation>
A two-pack type silicone sealing material (Silicone 70, manufactured by Yokohama Rubber Co., Ltd.) was placed on the joint of the outer wall material (Neoparier, manufactured by Nippon Electric Glass Co., Ltd.), and left for 24 hours at 20 ° C. and 50% RH. Next, each of the coating materials of Examples 1 to 3 and Comparative Examples 1 and 2 was applied to the surface of the placed silicone sealing material, left for 11 months outdoors, and then visually observed on the surface of the outer wall material. did. The case where there was little dirt around the joint was designated as “◯”, and the case where there was much dirt around the joint was designated as “X”.
The results are shown in Table 1.

Each component in Table 1 is as follows.
-Polymer (A) (hydrolyzable silyl group-containing polyisobutylene polymer): E100S, manufactured by Kaneka Corporation-Organotin compound (B) (dibutyltin-based): No. 918, manufactured by Sansha Co., Ltd. Solvent (C): n-hexane Primary amine (laurylamine): Farmin 20D, manufactured by Kao Corporation

As is apparent from the results shown in Table 1, the conventional coating materials (Comparative Examples 1 and 2) were darkened due to the extensive adhesion of dirt around the joints, whereas in Example 1, Reference Example 1, It was found that the coating material of No. 2 had a very excellent antifouling effect as compared with the conventional coating material, as it was only slightly contaminated near the boundary between the joint and the outer wall material.

Claims (7)

A hydrolyzable silyl group-containing polyisobutylene polymer (A), an organotin compound (B), a solvent (C), and further an amine (D) ;
The organotin compound (B) is contained in an amount of 0.5 to 10 parts by mass with respect to 100 parts by mass of the polymer (A),
0.1-5 parts by mass of the amine (D) is contained with respect to 100 parts by mass of the polymer (A),
A coating material for a silicone-based sealing material, which is applied to the surface of a silicone-based sealing material to prevent contamination by an elution component from the silicone-based sealing material.   The silicone-based sealing material coating material according to claim 1, wherein the organotin compound (B) is a tetravalent organotin compound.   The coating material for a silicone-based sealing material according to claim 1 or 2, wherein the amine (D) is a primary amine.   The said amine (D) is a laurylamine, The coating material for silicone type sealing materials in any one of Claims 1-3.   The silicone sealant coating material according to any one of claims 1 to 4, wherein the silicone sealant is cured or uncured. A silicone system for applying the silicone sealing material coating material according to any one of claims 1 to 5 on a surface of a cured silicone sealing material to prevent contamination by an elution component from the silicone sealing material. How to apply sealant coating material. Silicone which prevents the contamination by the elution component from the said silicone type sealing material by apply | coating the coating material for silicone type sealing materials in any one of Claims 1-5 on the surface of an uncured silicone type sealing material To apply coating material for the base sealant.