JP2000336310A - Primer composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a primer composition applicable even in the case of a polyisobutylene-based sealing material especially useful for a construction, widely useful for various members to be applied such as a window glass a coated surface a placing joint face of old sealing material a porous face, etc. SOLUTION: This primer composition comprises (A) an organopolysiloxane resin containing a hydroxyl group or an alkoxy group bonded to a silicon atom, (B) an amino group-containing silane compound, (C) a hydrolyzable silyl group- containing urethane prepolymer, (D) a tin (IV) compound and/or an organic titanic acid ester as a catalyst and (E) an organic solvent.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a primer composition,
More specifically, the present invention relates to a primer composition particularly useful for a polyisobutylene-based sealing material used as a building sealing material.

[0002]

2. Description of the Related Art Conventionally, silicone-based sealing materials have been mainly used as sealing materials for construction, particularly in terms of excellent durability and weather resistance. Polyisobutylene-based sealing materials are attracting attention as having high performance. Incidentally, primers for building sealing materials are generally broadly classified into silane-based primers and urethane-based primers. However, especially in the construction of the periphery of the window glass, since the influence of ultraviolet rays near the adhesive interface can be considered,
A high degree of weather resistance is required for the primer.
For this reason, at present, a silane-based primer containing a silicone-based compound having excellent weather resistance as a main component is used (see JP-A-2-219885). However, when a polyisobutylene-based sealing material is used in place of the silicone-based sealing material described above, in such a silane-based primer, the silicone compound has a different polarity from that of the polyisobutylene-based sealing material. I can't get it. In addition, silane primers are useful for inorganic adherends such as metal and glass,
Sufficient adhesion cannot be obtained for organic adherends having greatly different polarities. In recent years, as exterior walls for construction, weather-resistant, chemical-resistant, electrodeposition-coated or spray-painted acrylic resin paint or fluororesin paint with excellent electrical insulation properties have come to be used frequently. The development of a primer having excellent adhesion to these painted surfaces has been desired.

[0003] On the other hand, when the member to be processed has a porous surface, even if various kinds of painted surfaces or primers for window glass are applied, the ability to prevent permeation of the porous surface and water permeation to the bonding interface is not achieved. Since it is low, a primer dedicated to the porous surface is required separately. Therefore, if the types of members to be processed are different, it is necessary to apply different types of primers separately at joints where these members are to be joined, and it is inevitable that the process of the process is difficult.

[0004]

Means for Solving the Problems Accordingly, the present inventors have:
A general-purpose primer that can be applied to the above-mentioned polyisobutylene-based sealing material and that can contribute to the development of good adhesion (including adhesion weather resistance) to window glass, painted surfaces and porous members to be processed. As a result of intensive studies for providing the same, it has been found that these organic solvent solutions obtained by adding a catalyst to three specific primer components can be used as intended general-purpose primers, and the present invention has been completed.

That is, the present invention provides (A) an organopolysiloxane resin containing a hydroxyl group or an alkoxy group bonded to a silicon atom, (B) a silane compound containing an amino group,
(C) a hydrolyzable silyl group-containing urethane prepolymer,
(D) A primer composition comprising a tin (IV) compound and / or an organic titanate as a catalyst and (E) an organic solvent.

In the present invention, the organopolysiloxane resin (A) containing a hydroxyl group or an alkoxy group bonded to a silicon atom (hereinafter simply referred to as an organopolysiloxane resin) has, for example, an average unit of the formula:

Embedded image Wherein, R ¹ is a monovalent hydrocarbon group (e.g. methyl, ethyl, alkyl groups such as propyl; those substituted with and halogen or cyano group these hydrogen atoms; vinyl, alkenyl groups such as allyl); R ² Is a hydrogen atom or an alkyl group (methyl, ethyl, propyl, etc.);
1.8 and b are such that the number of hydroxyl groups or alkoxy groups bonded to silicon atoms in one molecule is one or more], and is usually 0.8 to 0.8 per silicon atom. Hydrochloride or a mixture of two or more chlorosilanes or alkoxysilanes each having ~ 1.8 monovalent hydrocarbon groups is hydrolyzed in water or a mixture of water and an organic solvent to produce hydrochloric acid, alcohol, and the like as a by-product. It can be manufactured by removing.

The amino group-containing silane compound (B) in the present invention includes, for example, aminomethyltrimethoxysilane, aminomethyltriethoxysilane, γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, γ-amino Propyltriaminoxysilane, γ- (2-aminoethyl) aminopropyltrimethoxysilane and the like.

In the present invention, the above-mentioned hydrolyzable silyl group-containing urethane prepolymer (C) (hereinafter simply referred to as silyl group-containing prepolymer) is first reacted in a molecule with an appropriate polyol and an excess amount of polyisocyanate. After obtaining a urethane prepolymer containing an isocyanate group (NCO) (an NCO-containing prepolymer), a functional group (amino group, mercapto group, epoxy group, etc.) reactive with an isocyanate group and a hydrolyzable group ( By performing an addition reaction with a silane compound having an alkoxy group, an acyloxy group, an amino group, an aminooxy group, a mercapto group, and the like (hereinafter, referred to as a silane coupling agent),
Can be manufactured. Examples of the polyol include glycol, triol, polyoxyalkylene polyol, modified polyether polyol, polytetramethylene ether glycol, condensation polyester polyol, lactone polyester polyol, and the like.
Among them, a polyoxyalkylene polyol having a molecular weight of about 1,000 to 3,000 is preferable. Examples of the polyisocyanate include tolylene diisocyanate, 4,4′-
Examples include diphenylmethane diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, lysine diisocyanate, isopropylidene bis (4-cyclohexyl isocyanate), and hydrogenated xylylene diisocyanate. Examples of the silane coupling agent include aminopropyltrimethoxysilane, γ-phenylaminopropyltrimethoxysilane, bis (trimethoxysilylpropyl) amine, N- (β-aminoethyl) -γ-aminopropyltrimethoxysilane, ureido Propyltriethoxysilane, N- (n-butyl)-
γ-aminopropyltrimethoxysilane, N- (cyclohexyl) -γ-aminopropyltrimethoxysilane,
γ-mercaptopropyltrimethoxysilane, N-methylaminopropyltrimethoxysilane, and the like.

The tin (IV) compound as the catalyst (D) in the present invention includes, for example, tin dioctylate, dibutyltin dilaurate, dibutyltin bisacetylacetate and the like. Further, the tin (I
V) Organic titanates (eg, tetraisopropyl titanate, tetra n
-Butyl titanate and a partially hydrolyzed condensate thereof, a titanium chelate compound such as titanium diisopropyl bisacetyl acetate, titanium diisopropyl bisethyl acetoacetate, etc.), and when used in combination, a tin (IV) compound and an organic titanium It is preferable that the weight ratio of the acid ester is selected to be 1: 5 to 1: 1. By using an organic titanate together, tin (I
V) Although the adhesiveness is improved as compared with the use of the compound alone, the adhesiveness to the porous surface is reduced when the organic titanate is used in combination exceeding the upper limit of the above range.

The organic solvent (E) in the present invention includes, for example, benzene, toluene, xylene, methanol, ethanol, isopropyl alcohol, butanol, ethylene glycol monomethyl ether, acetone, methyl ethyl ketone, ligroin, ethyl acetate, tetrahydrofuran, n-hexane , Heptane, trichloroethylene, perchloroethylene, etc., and one or more of these are used in appropriate combination.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION The primer composition according to the present invention comprises the above-mentioned organopolysiloxane resin (A), amino group-containing silane compound (B) and silyl group-containing prepolymer (C) as primer components. It is composed of a system obtained by dissolving the catalyst (D) in an organic solvent (E). Here, the amount of each of the primer components (A) to (C) is usually 0.5 to 5% (% by weight, the same applies hereinafter) for component (A), and 2% for component (B) in the total amount of the primer composition. ~
What is necessary is just to select so that it may become 10% and component (C) may be 6 to 15%. If the amount of the component (A) is less than 0.5%, the adhesion to glass tends to decrease, and if it exceeds 5%, the adhesion to the sealing material tends to decrease. When the amount of the component (B) is less than 2%, the adhesion to various members to be processed is reduced, and when it exceeds 10%, the storage stability tends to be deteriorated. When the amount of the component (C) is less than 6%, the adhesion to the sealing material and the porous surface is reduced, and when it exceeds 15%, the adhesion to the metal surface tends to be deteriorated. Also,
The amount of the catalyst (D) is usually 1 to the total amount of the components (A) to (C).
The amount may be selected in the range of 25 to 70 parts with respect to 00 parts (parts by weight, hereinafter the same). In addition, if necessary, ordinary inorganic fillers (fumed silica, colloidal silica, etc.),
An appropriate amount of a coloring agent (such as redwood, titanium oxide, carbon black, and dye) may be added.

The primer composition of the present invention having the above constitution can be applied to a polyisobutylene-based sealing material as described above. Among them, as a special mode, for example, a polysulfide-based sealing material already applied at a construction site is used. In order to renew this with the aging due to long-term aging (about 10 years or more), after scraping the aged polysulfide-based sealing material and continuing the polyisobutylene-based sealing material while leaving a very small part of it In addition, it is recognized that the primer performance can be sufficiently exhibited.

[0013]

Next, the present invention will be described more specifically with reference to examples and comparative examples. Examples 1 to 6 and Comparative Example 1 (1) Production of silyl group-containing prepolymer NCO-containing prepolymer A having the following theoretical NCO content was prepared by reacting 5 parts of tolylene diisocyanate with the following number of polyol mixtures under heating and stirring. , B, and C, and then 1. Aminopropyltrimethoxysilane or 2. γ-phenylaminopropyltrimethoxysilane is added to introduce a hydrolyzable silyl group (the addition reaction of the silane coupling agent is based on the theoretical NCO content of each NCO-containing prepolymer,
Equivalents), various silyl group-containing prepolymers A-
1,2; B-1,2; C-1,2. The silyl group-containing prepolymer A-1 means that one aminopropyltrimethoxysilane was added to the NCO-containing prepolymer A.

(2) Basic compound (corresponding to a conventional silane primer)

(3) Preparation of Primer Composition The basic compound of the above (2), the silyl group-containing prepolymer of the above (1) and dibutyltin bisacetylacetate as an additional catalyst are compounded in the number of parts shown in Table 1 below. Then, the mixture is stirred and mixed to obtain a primer composition. (4) Adhesion test The primer composition of the above (3) was applied to various members to be processed shown in Table 1 with a brush, air-dried at room temperature for 1 hour, and then a polyisobutylene-based sealing material (Sunstar Giken Co., Ltd. ) Made of “Penguin Seal 7000”), 20 ° C x 7
Curing for 5 days and 50 ° C. × 7 days. The tensile adhesion of the obtained specimen was determined according to JIS A5758, and the results are shown in Table 1.

[0016] Note 2) Two-component polysulfide-based sealing material [PS-
2 (A), PS-2 (B), PS-2 (C)], and cured and cured at 20 ° C. × 7 days. Criteria in Table 1: ○: Polysulfide-based sealing material or poly 100% cohesive failure of isobutylene-based sealing material △: 80 to less than 100% of the same cohesive failure ×: less than 80% of the same cohesive failure

[0017]

From the results in Table 1, it can be seen that the addition of the silyl group-containing prepolymer to the basic formulation (conventional silane primer) slightly reduces the adhesion to the aluminum plate (Examples 1, 3 to 3). 6) It is expected that the adhesion to the two-pack type polysulfide-based sealing material is improved. The joint property with respect to the surface of the two-pack type polysulfide-based sealing material was better when using 1 aminopropyltrimethoxysilane than when using 2γ-phenylaminopropyltrimethoxysilane as the silane coupling agent. Improvement is seen. Further, when a triol-rich polyol having a molecular weight of 3,000 is used as the polyol in the silyl group-containing prepolymer, better results are recognized. In addition, the primer composition of the present invention is useful mainly when a polyisobutylene-based sealing material for construction is used, but in addition to this, other sealing materials, further various adhesives, paints, It goes without saying that it can also be used as a primer for coating materials and the like.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Masaaki Murase 7-1, Akita-cho, Takatsuki-shi, Osaka Sunstar Giken Co., Ltd. F-term (reference) 4H017 AA04 AA31 AB03 AB07 AB14 AD05 AE03 4J038 DG292 DL051 GA03 GA09 GA15 JC35 JC38 JC39 KA03 KA04 KA06 PA07

Claims (6)

[Claims] 1. An organopolysiloxane resin containing a hydroxyl group or an alkoxy group bonded to a silicon atom, (B) a silane compound containing an amino group, (C) a urethane prepolymer containing a hydrolyzable silyl group, and (D) a catalyst. A primer composition comprising: a tin (IV) compound and / or an organic titanate; and (E) an organic solvent. 2. Component (A) in the total amount of the primer composition
The primer composition according to claim 1, wherein the content is 0.5 to 5% by weight, 2 to 10% by weight of the component (B), and 6 to 15% by weight of the component (C). 3. The amount of the catalyst (D) depends on the amount of the components (A) to (C).
The primer composition according to claim 1 or 2, wherein the total amount of the primer composition is 25 to 70 parts by weight based on 100 parts by weight. 4. The method according to claim 1, wherein the tin (IV) compound and the organic titanate are used in combination, and the weight ratio of the tin (IV) compound to the organic titanate is 1: 5 to 1: 1. The primer composition according to any one of the preceding claims. 5. The primer composition according to claim 1, which is for a polyisobutylene-based sealing material. 6. The primer composition according to claim 1, which is used for joining to a surface of a polysulfide-based sealing material.