JP6101097B2 - Primer composition - Google Patents

Description

  The present invention relates to a primer composition suitably used as a primer for a sealing material.

  Conventionally, a sealing material is filled in a joint portion or a gap between members in a structure such as a building or an automobile, thereby improving the watertightness and airtightness of the structure. However, when the adhesion of the sealing material to the member is low, the adhesion between the sealing material and the member is improved by pre-coating the primer composition on the member in advance.

  Therefore, the primer composition is required to have excellent adhesion to each of the sealing material and the member. Here, examples of the sealing material include silicone, modified silicone, and polyurethane. Examples of the member include glass, aluminum, concrete, ceramics, and mortar. As described above, various kinds of sealing materials and members are used. However, the primer composition cannot exhibit excellent adhesion to all the sealing materials and members, and the adhesion of the primer composition may be lowered depending on the type of the sealing material and members. Therefore, conventionally, a primer composition is selected and used according to the kind of the sealing material and the member, and the work is complicated. For these reasons, the primer composition is required to exhibit excellent adhesion to more sealing materials and members.

  Therefore, Patent Document 1 discloses a primer composition containing a) a polyisocyanate, b) a condensate of alkoxysilane containing trialkoxysilane, c) a silane compound such as an aminosilane compound and a ketimine silane compound, and d) a film-forming resin. Is disclosed. Such a primer composition can exhibit excellent adhesion to various kinds of sealing materials and members.

JP 2006-1975

  However, in order to improve the corrosion resistance, a member made of a metal such as aluminum may be subjected to surface treatment such as electrodeposition coating such as acrylic resin or melamine-acrylic resin or alumite treatment. The adhesion of the conventional primer composition was still low for the member subjected to such a surface treatment. For this reason, the primer composition is required to further improve the adhesiveness to difficult-to-adhere members such as members subjected to surface treatment.

  In addition, when a structure using the primer composition is exposed to a high temperature and high humidity environment such as summer for a long period of time, there is a problem that the adhesive strength of the cured product of the conventional primer composition is lowered. Accordingly, there is a need for improving the heat and heat resistance of the primer composition.

  Furthermore, when the structure is used for a long period of time in winter or in a cold region, the cured product of the primer composition repeatedly freezes and thaws according to changes in the temperature, and accordingly the cured product of the primer composition In some cases, the adhesive strength decreased. Accordingly, there is also a need for improving the freeze-thaw resistance of the primer composition.

  Then, the objective of this invention is providing the primer composition which is excellent in the adhesiveness with respect to a hard-to-adhere member, wet heat resistant adhesiveness, and freeze-thaw resistant adhesiveness.

  The primer composition of the present invention comprises a reaction product (A) of an alicyclic polyisocyanate and a polyol, a reaction product (B) of a polyisocyanate having an isocyanurate ring and a diol having a number average molecular weight of 200 to 1500, and An epoxy silane compound (C) is contained.

[Reactant (A)]
The reactant (A) is preferably a urethane prepolymer formed by reacting an alicyclic polyisocyanate and a polyol to form a urethane bond. Moreover, it is preferable that the reaction product (A) does not have an isocyanurate ring.

  The alicyclic polyisocyanate used for the reactant (A) has an alicyclic skeleton in one molecule, and has two or more isocyanate groups, and at least one isocyanate group is bonded to the alicyclic skeleton. It is a compound.

  Examples of the alicyclic polyisocyanate include cyclohexane diisocyanate, methylene bis (cyclohexyl isocyanate), isophorone diisocyanate (IPDI), bicycloheptane triisocyanate, and aromatic polyisocyanate water additives. An alicyclic polyisocyanate may be used individually by 1 type, and 2 or more types may be used together.

  Aromatic polyisocyanates include bis (isocyanatomethyl) benzene (XDI), 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 1,4-phenylene diisocyanate, diphenylmethane diisocyanate, triphenylmethane triisocyanate, And polymethylene polyphenyl isocyanate. Specific examples of the water additive of the aromatic polyisocyanate include 1,3-bis (isocyanatomethyl) cyclohexane (hydrogenated XDI).

  Of these, isophorone diisocyanate and 1,3-bis (isocyanatomethyl) cyclohexane are preferred as the alicyclic polyisocyanate.

  The polyol used for the reactant (A) is a compound having two or more hydroxy groups in one molecule.

  Examples of polyols include ethylene glycol, diethylene glycol, 1,4-butanediol, 1,6-hexanediol, neoventyl glycol, trimethylolpropane, glycerin, triethanolamine, sorbitol, polyether polyol, polyester polyol, poly Examples include caprolactone polyol, polyalkylene polyol, and polycarbonate polyol. These polyols may be used individually by 1 type, and may use 2 or more types together.

  Examples of the polyether polyol include polyethylene glycol, polypropylene glycol, polytetramethylene glycol, random copolymers and block copolymers thereof, and polyoxyalkylene-modified products of bisphenol A.

  Examples of the polyester polyol include a polyester polyol obtained by a reaction between a polyvalent carboxylic acid and a diol compound. Polycarboxylic acids include terephthalic acid, isophthalic acid, dodecanedioic acid, 1,5-naphthalic acid, 2,6-naphthalic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacin Examples thereof include dicarboxylic acids such as acid, decamethylene dicarboxylic acid, and dodecamethylene dicarboxylic acid. Examples of the diol compound include propylene glycol, 1,3-propanediol, 1,4-butanediol, neopentyl glycol, 1,5-pentanediol, 1,6-hexanediol, ethylene glycol, diethylene glycol, and cyclohexanediol. Etc.

  Examples of the polycaprolactone polyol include polycaprolactone polyol obtained by ring-opening addition polymerization of a lactone compound to a polyol compound. As a polyol compound, the thing similar to the polyol compound mentioned in the polyester polyol is mentioned. Examples of the lactone compound include β-propiolactone, pivalolactone, δ-valerolactone, ε-caprolactone, methyl-ε-caprolactone, dimethyl-ε-caprolactone, and trimethyl-ε-caprolactone.

  Examples of the polyalkylene polyol include polybutadiene polyol, hydrogenated polybutadiene polyol, and hydrogenated polyisoprene polyol.

  Examples of the polycarbonate polyol include polyhexamethylene carbonate polyol and polycyclohexanedimethylene carbonate polyol.

  Especially, as a polyol used for a reaction material (A), a trimethylol propane is preferable.

  In the synthesis of the reactant (A), the polyol is heated and melted, and then the alicyclic polyisocyanate is added to the melted polyol in a nitrogen atmosphere to react the polyol with the alicyclic polyisocyanate. Is done.

  In the reaction between the polyol and the alicyclic polyisocyanate, the molar ratio ([NCO] / [OH]) of the total of isocyanate groups (NCO) of the alicyclic polyisocyanate and the total of hydroxy groups (OH) of the polyol. ) Is preferably 1.0 to 5.0. If the molar ratio ([NCO] / [OH]) is less than 1.0, the primer composition may not be able to form a film after curing. On the other hand, if the molar ratio ([NCO] / [OH]) exceeds 5.0, a large amount of free isocyanate groups may inhibit the curing of the primer composition.

[Reactant (B)]
The reactant (B) is preferably a urethane prepolymer formed by reacting a polyisocyanate having an isocyanurate ring with a diol having a number average molecular weight of 200 to 1500 to form a urethane bond.

  The polyisocyanate having an isocyanurate ring used in the reactant (B) has a ring structure formed by polymerizing three isocyanate groups (—NCO) in one molecule, and two isocyanate groups. It is a compound having the above.

  The isocyanate group to be polymerized to form an isocyanurate ring may be an isocyanate group possessed by a polyisocyanate compound such as an aromatic polyisocyanate compound, an aliphatic polyisocyanate compound, and an alicyclic polyisocyanate compound. Especially, the isocyanate group which an aliphatic polyisocyanate compound and an alicyclic polyisocyanate compound have is preferable.

  Examples of the aliphatic polyisocyanate compound include ethylene diisocyanate, propylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate (HDI), dicyclohexylmethane diisocyanate, 1,6,11-undecane triisocyanate, 1,3,6-hexamethylene triisocyanate, Examples include trimethylhexamethylene diisocyanate. Examples of the alicyclic polyisocyanate compound include isophorone diisocyanate (IPDI) and bicycloheptane triisocyanate.

  Preferred examples of the polyisocyanate having an isocyanurate ring include hexamethylene diisocyanate (HDI) isocyanurate and isophorone diisocyanate (IPDI) isocyanurate. The polyisocyanate having an isocyanurate ring may be used alone or in combination of two or more.

  Commercially available products can also be used as the polyisocyanate having an isocyanurate ring. For example, as a commercially available product of IPDI isocyanurate, a product name “VESTANAT T1890E” manufactured by Evonik Degussa Co., Ltd. may be mentioned. In addition, as commercial products of HDI isocyanurate bodies, trade names “Duranate TPA-100”, “Duranate TKA-100”, “Duranate MFA-75B”, “Duranate MHG-80B”, and “Duranate” manufactured by Asahi Glass Chemical Co., Ltd. TLA-100 "etc. are mentioned.

  The number average molecular weight of the diol used in the reactant (B) is limited to 200 to 1500, but 300 to 1200 is preferable. If the number average molecular weight of the diol is too low, the cured product of the primer composition may not exhibit excellent flexibility. Moreover, when the number average molecular weight of diol is too high, the cured | curing material of a primer composition may become soft too much and there exists a possibility that adhesiveness may fall.

In the present invention, the number average molecular weight of the diol is a value determined by polystyrene conversion using gel permeation chromatography (GPC). For example, it can be measured with the following measuring apparatus and measurement conditions.
Product name “HLC-8121GPC / HT” manufactured by TOSOH
Measurement conditions Column: TSKgelGMHHR-H (20) HT x 3
TSK guard column-HHR (30) HT x 1
Mobile phase: o-DCB 1.0 mL / min
Sample concentration: 1 mg / mL
Detector: Bryce refractometer
Standard substance: polystyrene (Molecular weight: 500-8420000, manufactured by TOSOH)
Elution conditions: 145 ° C
SEC temperature: 145 ° C

  Examples of the diol used in the reaction product (B) include polyethylene glycol, polypropylene glycol, and polytetramethylene glycol. Diol may be used individually by 1 type and 2 or more types may be used together. According to the reaction product (B) using a diol, it is possible to provide a primer composition that is excellent in adhesiveness and can exhibit excellent flexibility after curing. Of these, polyethylene glycol and polypropylene glycol are preferable.

  A commercial item can also be used as polypropylene glycol. Examples of commercially available products include “Excenol 420” and “Excenol 720” manufactured by Asahi Glass Co., Ltd.

  The content of the reactant (B) in the primer composition is preferably 5 to 500 parts by weight and more preferably 30 to 300 parts by weight with respect to 100 parts by weight of the reactant (A). If the content of the reactant (B) is too low, the heat and moisture resistance and freeze-thaw resistance of the primer composition may be lowered. Moreover, when content of a reaction material (B) is too high, there exists a possibility that the hardened | cured material of a primer composition may become too flexible.

[Epoxysilane compound (C)]
The epoxysilane compound (C) is a compound containing a hydrolyzable silyl group and a functional group having an epoxy group or an epoxy group in one molecule.

  The hydrolyzable silyl group is a group in which the hydrolyzable group is bonded to a silicon atom. Examples of the hydrolyzable group include a hydrogen atom, a halogen atom, an alkoxy group, an acyl oxide group, a ketoximate group, an amino group, an amide group, an acid amide group, an aminooxy group, a mercapto group, and an alkenyl oxide group. .

  As the hydrolyzable silyl group, an alkoxysilyl group in which an alkoxy group is bonded to a silicon atom is preferable because no harmful by-product is formed after the reaction. Examples of the alkoxy group include a methoxy group, an ethoxy group, a propyloxy group, an isopropyloxy group, an n-butoxy group, a t-butoxy group, a phenoxy group, and a benzyloxy group. preferable.

  Examples of the epoxy silane compound (C) include γ-glycidoxypropyldimethylethoxysilane, γ-glycidoxypropylmethyldimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, and γ-glycidoxypropylmethyldiethoxysilane. , Γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, β- (3,4-epoxycyclohexylsil) ethylmethyltrimethoxysilane, and β- (3,4-epoxycyclohexyl) ethyl Examples include methyldimethoxysilane. An epoxysilane compound (C) may be used individually by 1 type, and 2 or more types may be used together.

  Of these, as the epoxysilane compound (C), γ-glycidoxypropylmethyldiethoxysilane, γ-glycidoxypropyltrimethoxysilane, and γ-glycidoxypropyltriethoxysilane are preferable.

  A commercially available product can also be used as the epoxysilane compound (C). Examples include trade names “KBM-303”, “KBM-402”, “KBM-403”, “KBE-402”, and “KBE-403” manufactured by Shin-Etsu Chemical Co., Ltd.

  The content of the epoxysilane compound (C) in the primer composition is preferably 5 to 50 parts by weight, more preferably 10 to 40 parts by weight, with respect to 100 parts by weight of the reactant (A). Is particularly preferred. If the content of the epoxysilane compound (C) is too low, the heat and moisture resistance and freeze-thaw resistance of the primer composition may be lowered. Moreover, when content of a reaction material (B) is too high, there exists a possibility that the hardened | cured material of a primer composition may become too flexible.

[Other ingredients]
The primer composition of the present invention may contain other components such as a solvent such as ethyl acetate and butyl acetate, an antioxidant, an ultraviolet absorber, and a filler, if necessary.

(Antioxidant)
Antioxidants include 2,6-di-t-butyl-4-methylphenol, n-octadecyl-3- (4′-hydroxy-3 ′, 5′-di-t-butylphenyl) propionate, 2, 2′-methylenebis (4-methyl-6-tert-butylphenol), 2,2′-methylenebis (4-ethyl-6-tert-butylphenol), 2,4-bis (octylthiomethyl) -o-cresol, 2 -T-Butyl-6- (3-t-butyl-2-hydroxy-5-methylbenzyl) -4-methylphenyl acrylate, 2,4-di-t-amyl-6- [1- (3,5 -Di-t-amyl-2-hydroxyphenyl) ethyl] phenyl acrylate, 2- [1- (2-hydroxy-3,5-di-tert-pentylphenyl)] acrylate, tetrakis [methylene-3- ( , 5-di-tert-butyl-4-hydroxyphenyl) propionate] hindered phenolic antioxidants such as methane; dilauryl thiodipropionate, lauryl stearyl thiodipropionate, pentaerythritol tetrakis (3-laurylthiopro) Sulfur-based antioxidants such as Pionate; and phosphorus-based antioxidants such as Tris (nonylphenyl) phosphite and Tris (2,4-di-t-butylphenyl) phosphite. An antioxidant may be used individually by 1 type and may use 2 or more types together.

(UV absorber)
Examples of the ultraviolet absorber include 2- (2′-hydroxy-5′-methylphenyl) benzotriazole, 2- (2′-hydroxy-3 ′, 5′-t-butylphenyl) benzotriazole, 2- (2 ′ -Hydroxy-3 ', 5'-di-t-butylphenyl) -5-chlorobenzotriazole and other benzotriazole ultraviolet absorbers; 2-hydroxy-4-methoxybenzophenone and other benzophenone ultraviolet absorbers; salicylic acid ester Examples include ultraviolet absorbers, cyanoacrylate ultraviolet absorbers; hindered amine light stabilizers. An ultraviolet absorber may be used individually by 1 type, and may use 2 or more types together.

(filler)
Examples of the filler include mica, calcium carbonate, kaolin, talc, titanium oxide, diatomaceous earth, urea resin, styrene beads, calcined clay, and starch.

  The primer composition of the present invention is preferably used for applying a sealing material. By using the primer composition of this invention, the adhesiveness of a sealing material and the member which comprises structures, such as a building and a motor vehicle, can be improved.

  Examples of the sealing material include silicone, modified silicone, polysulfide, polyurethane, acrylic urethane, acrylic, SBR, butyl rubber, and polyisobutylene.

  Examples of the material constituting the member include metals such as aluminum, iron, and stainless steel, glass, mortar, gypsum, concrete, and ceramics. In order to improve the corrosion resistance, the metal member may be subjected to surface treatment such as electrodeposition coating such as acrylic resin or melamine-acrylic resin or alumite treatment.

  The primer composition of the present invention is particularly preferably used for improving the adhesion between a member made of a surface-treated metal and a sealing material. In the conventional primer composition, it was difficult to exhibit excellent adhesiveness to a member made of a surface-treated metal. Therefore, the effect of the present invention can be exhibited to the maximum by using the primer composition of the present invention for such a hardly adhesive member.

  As a method for using the primer composition of the present invention, for example, the primer composition is applied to the surface of the member constituting the structure and cured, and then a sealing material is filled in the joint or gap of the member. What is necessary is just to harden. The primer composition may be applied at least to the surface of the member surface to which the sealing material is applied.

  The primer composition of the present invention can not only exhibit excellent adhesion to difficult-to-adhere members such as members made of metal that has been surface-treated, but also has moisture and heat resistance and freeze-thaw resistance. Are compatible. Therefore, a structure in which a sealing material and a member are bonded with such a primer composition is used over a long period of time in a high temperature and high humidity environment (temperature of 50 ° C. or higher, relative humidity of 80% or higher) such as summer. Even so, the primer composition can maintain excellent adhesion. In addition, even if the above structure is used for a long period of time in a low temperature environment such as winter and cold regions, and the cured product of the applied primer composition is repeatedly frozen and thawed, the adhesion of the primer composition The decrease is highly suppressed. Therefore, even if the structure using the primer composition of the present invention is used for many years, excellent adhesion between the sealing material and the member can be maintained.

  Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited thereto.

Example 1
A mixture was obtained by mixing 79 g of isophorone diisocyanate (IPDI) and 21 g of trimethylolpropane (TMP). At this time, the molar ratio ([NCO] / [OH]) of the total of isocyanate groups (NCO) of isophorone diisocyanate and the total of hydroxy groups (OH) of trimethylolpropane was 1.5. Next, 133.3 g of ethyl acetate and 33.3 g of butyl acetate were added to the mixture, and these were reacted by stirring for 3 hours while heating to 80 ° C. Thereby, the prepolymer solution (I) containing the reaction product (A1) formed by reacting isophorone diisocyanate and trimethylolpropane to form a urethane bond, ethyl acetate and butyl acetate was obtained.

  Next, 57.6 g of isocyanurate of hexamethylene diisocyanate (HDI) (trade name “Duranate TPA-100” manufactured by Asahi Kasei Chemical Co., Ltd.) and polypropylene glycol (PPG, number average molecular weight (Mn) 400, manufactured by Asahi Glass Co., Ltd.) The mixture was obtained by mixing 42.4 g of the name “Exenol 420”. At this time, the molar ratio ([NCO] / [OH]) of the total of isocyanate groups (NCO) of the isocyanurate of hexamethylene diisocyanate to the total of hydroxy groups (OH) of polypropylene glycol was 1.5. Met. The mixture was then reacted by stirring for 3 hours while heating to 80 ° C. Thereby, the isocyanurate body of hexamethylene diisocyanate and polypropylene glycol (Mn400) reacted to form a reaction product (B1) formed with a urethane bond.

  Then, 50 g of the reaction product (B1) and epoxysilane compound (C1) (γ-glycidoxypropyltrimethoxysilane, manufactured by Shin-Etsu Silicone Co., Ltd.) are added to the total amount (266.6 g) of the prepolymer solution (I) prepared above. The name “KBM-403”) 16.7 g was added and mixed to obtain a primer composition.

(Example 2)
In the preparation of the prepolymer solution (I), instead of 133.3 g of ethyl acetate and 33.3 g of butyl acetate, 266.7 g of ethyl acetate and 66.7 g of butyl acetate were used. Further, in the preparation of the primer composition, Primer composition in the same manner as in Example 1, except that 200 g of the reactant (B1) and 33.3 g of the epoxysilane compound (C1) were added to the total amount (433.4 g) of the prepared prepolymer solution (I). Got.

(Example 3)
A mixture was obtained by mixing 76.4 g of 1,3-bis (isocyanatomethyl) cyclohexane and 23.6 g of trimethylolpropane (TMP). At this time, the molar ratio ([NCO] / [OH]) of the total of isocyanate groups (NCO) of 1,3-bis (isocyanatomethyl) cyclohexane and the total of hydroxy groups (OH) of trimethylolpropane. Was 1.5. Next, 133.3 g of ethyl acetate and 33.3 g of butyl acetate were added to the mixture, and these were reacted by stirring for 3 hours while heating to 80 ° C. Thereby, 1,3-bis (isocyanatomethyl) cyclohexane and trimethylolpropane react to form a urethane bond to form a reaction product (A2), a prepolymer solution (II) containing ethyl acetate and butyl acetate. Obtained.

  Next, a reaction product (B1) formed by reacting an isocyanurate of hexamethylene diisocyanate (HDI) with polypropylene glycol (Mn400) to form a urethane bond in the same manner as in Example 1.

  Then, to the total amount (266.6 g) of the prepolymer solution (II), 50 g of the reaction product (B1), epoxy silane compound (C1) (3-glycidoxypropyltrimethoxysilane, manufactured by Shin-Etsu Silicone Co., Ltd., trade name “KBM- 403 ") 16.7 g was added and mixed to obtain a primer composition.

Example 4
Hexamethylene diisocyanate (HDI) isocyanurate (trade name “Duranate TPA-100” manufactured by Asahi Kasei Chemical Co., Ltd.) 73.1 g, and polypropylene glycol (PPG, number average molecular weight (Mn) 200, product name manufactured by Sanyo Chemical Industries, Ltd. The mixture was obtained by mixing 26.9 g of Sanniks PP-200 "). At this time, the molar ratio ([NCO] / [OH]) of the total of isocyanate groups (NCO) of the isocyanurate of hexamethylene diisocyanate to the total of hydroxy groups (OH) of polypropylene glycol was 1.5. Met. The mixture was then reacted by stirring for 3 hours while heating to 80 ° C. Thereby, the isocyanurate body of hexamethylene diisocyanate and polypropylene glycol (Mn200) reacted to form a reaction product (B2) formed with a urethane bond.

  A primer composition was obtained in the same manner as in Example 1 except that 50 g of the reaction product (B2) synthesized according to the above procedure was added to the prepolymer solution (I).

(Example 5)
Hexamethylene diisocyanate (HDI) isocyanurate (trade name “Duranate TPA-100” manufactured by Asahi Kasei Chemical Co., Ltd.) 32.2 g and polypropylene glycol (PPG, number average molecular weight (Mn) 1200, product name manufactured by Sanyo Chemical Industries, Ltd. A mixture was obtained by mixing 67.8 g of SANNICS PP-1200 "). At this time, the molar ratio ([NCO] / [OH]) of the total of isocyanate groups (NCO) of the isocyanurate of hexamethylene diisocyanate to the total of hydroxy groups (OH) of polypropylene glycol was 1.5. Met. The mixture was then reacted by stirring for 3 hours while heating to 80 ° C. Thereby, the isocyanurate body of hexamethylene diisocyanate and polypropylene glycol (Mn1200) reacted to form a reaction product (B3) formed with a urethane bond.

  A primer composition was obtained in the same manner as in Example 1 except that 50 g of the reaction product (B3) synthesized according to the above procedure was added to the prepolymer solution (I).

(Example 6)
55 g of an isocyanurate form of isophorone diisocyanate (IPDI) (trade name “Destanat T1890” manufactured by Evonik Degussa) and 45 g of polypropylene glycol (PPG, number average molecular weight (Mn) 400, product name “Excenol 420”) manufactured by Asahi Glass Co., Ltd. A mixture was obtained by mixing. At this time, the molar ratio ([NCO] / [OH]) of the total of isocyanate groups (NCO) of the isocyanurate form of isophorone diisocyanate (IPDI) and the total of hydroxy groups (OH) of polypropylene glycol is 1 .5. The mixture was then reacted by stirring for 3 hours while heating to 80 ° C. Thereby, the isocyanurate body of isophorone diisocyanate (IPDI) and the polypropylene glycol (Mn400) reacted, and the reaction product (B4) formed by forming a urethane bond was obtained.

  A primer composition was obtained in the same manner as in Example 1 except that 50 g of the reaction product (B4) synthesized according to the above procedure was added to the prepolymer solution (I).

(Example 7)
58 g of isocyanurate of hexamethylene diisocyanate (HDI) (trade name “Duranate TPA-100” manufactured by Asahi Kasei Chemical) and polyethylene glycol (PEG, number average molecular weight (Mn) 400, product name “PEG # 400” manufactured by Lion Corporation) ) 42 g were mixed to obtain a mixture. At this time, the molar ratio ([NCO] / [OH]) of the total of isocyanate groups (NCO) of the isocyanurate of hexamethylene diisocyanate and the total of hydroxy groups (OH) of polyethylene glycol is 1.5. Met. The mixture was then reacted by stirring for 3 hours while heating to 80 ° C. Thereby, the isocyanurate body of hexamethylene diisocyanate and polyethyleneglycol (Mn400) reacted, and the reaction product (B5) formed by forming a urethane bond was obtained.

  A primer composition was obtained in the same manner as in Example 1 except that 50 g of the reaction product (B5) synthesized according to the above procedure was added to the prepolymer solution (I).

(Example 8)
Except for using 16.7 g of epoxysilane compound (C2) (γ-glycidoxypropylmethyldiethoxysilane, trade name “KBM-402” manufactured by Shin-Etsu Silicone Co., Ltd.) instead of epoxysilane compound (C1) In the same manner as in Example 1, a primer composition was obtained.

Example 9
Example except that 16.7 g of the epoxy silane compound (C3) (γ-glycidoxypropyltriethoxysilane, trade name “KBE-403” manufactured by Shin-Etsu Silicone Co., Ltd.) was used instead of the epoxy silane compound (C1). In the same manner as in No. 1, a primer composition was obtained.

(Comparative Example 1)
In the preparation of the prepolymer solution (I), 88.9 g of ethyl acetate and 22.2 g of butyl acetate were used instead of 133.3 g of ethyl acetate and 33.3 g of butyl acetate. Further, in the preparation of the primer composition, A primer composition was obtained in the same manner as in Example 1 except that 11.1 g of the epoxysilane compound (C1) was added to the prepared prepolymer solution (I) without adding the reactant (B1).

(Comparative Example 2)
A primer composition was obtained in the same manner as in Example 1 except that the epoxysilane compound (C1) was not added to the prepolymer solution (I).

(Comparative Example 3)
Instead of the epoxy silane compound (C1), 16.7 g of ketimine silane compound (3-triethoxysilyl-N- (1,3-dimethyl-butylidene) propylamine, manufactured by Shin-Etsu Silicone Co., Ltd., trade name “KBM-9103”) is used. A primer composition was obtained in the same manner as in Example 1 except that.

(Comparative Example 4)
A mixture is obtained by mixing 16 g of isocyanurate of hexamethylene diisocyanate (HDI) (trade name “Duranate TPA-100” manufactured by Asahi Kasei Chemical Co., Ltd.) and 84 g of dipropylene glycol (DPG, number average molecular weight (Mn) 134). It was. At this time, the molar ratio ([NCO] / [OH]) of the total of isocyanate groups (NCO) of the isocyanurate of hexamethylene diisocyanate to the total of hydroxy groups (OH) of dipropylene glycol is 1. It was 5. The mixture was then reacted by stirring for 3 hours while heating to 80 ° C. Thereby, the isocyanurate body of hexamethylene diisocyanate and the dipropylene glycol (Mn134) reacted, and the reaction product (B6) formed by forming a urethane bond was obtained.

  A primer composition was obtained in the same manner as in Example 1 except that 50 g of the reaction product (B6) synthesized according to the above procedure was added to the prepolymer solution (I).

(Comparative Example 5)
Hexamethylene diisocyanate (HDI) isocyanurate (product name “Duranate TPA-100” manufactured by Asahi Kasei Chemical Co., Ltd.) 22 g, and polypropylene glycol (PPG, number average molecular weight (Mn) 2000, product name “Exenol 2020” manufactured by Asahi Glass Co., Ltd.) ) 78 g was mixed to obtain a mixture. At this time, the molar ratio ([NCO] / [OH]) of the total of isocyanate groups (NCO) of the isocyanurate of hexamethylene diisocyanate to the total of hydroxy groups (OH) of polypropylene glycol was 1.5. Met. The mixture was then reacted by stirring for 3 hours while heating to 80 ° C. Thereby, the isocyanurate body of hexamethylene diisocyanate and polypropylene glycol (Mn2000) reacted to form a reaction product (B7) formed with a urethane bond.

  A primer composition was obtained in the same manner as in Example 1 except that 50 g of the reaction product (B7) synthesized according to the above procedure was added to the prepolymer solution (I).

(Comparative Example 6)
60 g of isocyanurate of hexamethylene diisocyanate (HDI) (trade name “Duranate TPA-100” manufactured by Asahi Kasei Chemical Co., Ltd.) and polypropylene glycol monomethacrylate (PPGM: number average molecular weight (Mn) having one hydroxy group in one molecule ) 400, manufactured by NOF Corporation, trade name “Blenmer PP-500”) 40 g was mixed to obtain a mixture. At this time, the molar ratio ([NCO] / [OH]) of the total of isocyanate groups (NCO) of the isocyanurate of hexamethylene diisocyanate to the total of hydroxy groups (OH) of polypropylene glycol was 1.5. Met. The mixture was then reacted by stirring for 3 hours while heating to 80 ° C. Thereby, the isocyanurate body of hexamethylene diisocyanate and polypropylene glycol monomethacrylate (Mn400) reacted to form a reaction product (B8) formed with a urethane bond.

  A primer composition was obtained in the same manner as in Example 1 except that 50 g of the reaction product (B8) synthesized according to the above procedure was added to the prepolymer solution (I).

(Comparative Example 7)
Hexamethylene diisocyanate (HDI) isocyanurate (product name “Duranate TPA-100” manufactured by Asahi Kasei Chemical Co., Ltd.) 66 g, and polyoxypropylene triol (POPTO, number average molecular weight (Mn) 400, product name “Sun” A mixture was obtained by mixing 34 g of Knicks GP400 "). At this time, the molar ratio ([NCO] / [OH]) of the total of isocyanate groups (NCO) of the isocyanurate of hexamethylene diisocyanate and the total of hydroxy groups (OH) of polyoxypropylene triol is 1 .5. The mixture was then reacted by stirring for 3 hours while heating to 80 ° C. Thereby, the isocyanurate body of hexamethylene diisocyanate and polyoxypropylene triol (Mn400) reacted to form a reaction product (B9) formed with a urethane bond.

  A primer composition was obtained in the same manner as in Example 1 except that 50 g of the reaction product (B9) synthesized according to the above procedure was added to the prepolymer solution (I).

(Comparative Example 8)
By mixing 61 g of hexamethylene diisocyanate (HDI) (trade name “Duranate D-101” manufactured by Asahi Kasei Chemical Co., Ltd.) and 39 g of polypropylene glycol (PPG, number average molecular weight Mn400, product name “Exenol 420” manufactured by Asahi Glass Co., Ltd.) A mixture was obtained. At this time, the molar ratio ([NCO] / [OH]) of the total of isocyanate groups (NCO) of hexamethylene diisocyanate of hexamethylene diisocyanate and the total of hydroxy groups (OH) of polypropylene glycol is 1.5. Met. The mixture was then reacted by stirring for 3 hours while heating to 80 ° C. Thereby, the reaction product (B10) formed by reacting hexamethylene diisocyanate and polypropylene glycol (Mn400) to form a urethane bond was obtained.

  A primer composition was obtained in the same manner as in Example 1 except that 50 g of the reaction product (B10) synthesized according to the above procedure was added to the prepolymer solution (I).

  Reactants (A1) to (A2), reactants (B1) to (B10), and epoxysilane compounds (C1) to (C3) in each of the primer compositions produced in Examples 1 to 9 and Comparative Examples 1 to 8. ), Aminosilane compound, ethyl acetate, and butyl acetate in amounts (parts by weight) were as shown in Table 1, respectively.

[Evaluation]
The room temperature adhesion, wet heat resistance, and freeze-thaw resistance of the primer composition to the anodized aluminum substrate were evaluated according to the following procedures. The results are shown in Table 1.

[Room temperature adhesion]
The primer composition was applied to one surface of the aluminum substrate that had been anodized, and cured for 14 days in a temperature environment of 23 ° C., thereby obtaining a cured film (thickness 50 μm) of the primer composition. A cross-cut test was performed on the cured film of the primer composition in accordance with JIS K5400 as described later.

[Moisture and heat resistance]
A primer composition is applied to one surface of an alumite-treated aluminum substrate and cured for 14 days in an environment of a temperature of 23 ° C. and a relative humidity of 50%, whereby a cured film (thickness 50 μm) of the primer composition is formed. Obtained. Next, the aluminum substrate on which the cured film of the primer composition is formed is left for 7 days in an environment having a temperature of 50 ° C. and a relative humidity of 80%, and then placed in an environment having a temperature of 23 ° C. and a relative humidity of 50%. Left for 1 day. Then, a cross-cut test was performed on the cured film of the primer composition after being allowed to stand in accordance with JIS K5400 as described later.

[Freeze-thaw resistant adhesive]
A primer composition is applied to one surface of an alumite-treated aluminum substrate and cured for 14 days in an environment of a temperature of 23 ° C. and a relative humidity of 50%, whereby a cured film (thickness 50 μm) of the primer composition is formed. Obtained. Next, the aluminum substrate on which the cured film of the primer composition is formed is left for 14 days in an environment at a temperature of −20 ° C., and then immersed in water at a water temperature of 20 ° C. for 1 hour. As one cycle, the process was performed 100 cycles. Thereafter, the aluminum substrate on which the cured film of the primer composition was formed was left in an environment of a temperature of 23 ° C. and a relative humidity of 50% for 1 day. Then, a cross-cut test was performed on the cured film of the primer composition after being allowed to stand in accordance with JIS K5400 as described later.

[Cross-cut test]
First, six square cuts were made at equal intervals in the cured film of the primer composition to create 25 square cells. Next, after sticking the adhesive tape to the cured film of the primer composition, the adhesive tape was peeled off, and the number of squares of the cured film of the primer composition peeled off from the aluminum substrate along with the peeling of the adhesive tape was measured. In Table 1, “◎”, “◯”, “Δ”, and “×” are as follows.
(Double-circle): The number of the squares which peeled was 0 piece.
○: The number of peeled cells was 1 to 5.
(Triangle | delta): The number of the squares which peeled was 6-20.
X: The number of squares peeled off was 21 to 25.

Claims (7)

  A reaction product (A) of an alicyclic polyisocyanate and a polyol, a reaction product (B) of an isocyanate having an isocyanurate ring and a diol having a number average molecular weight of 200 to 1500, and an epoxysilane compound (C) The primer composition characterized by the above-mentioned.   The primer composition according to claim 1, wherein the alicyclic polyisocyanate contains isophorone diisocyanate and / or 1,3-bis (isocyanatomethyl) cyclohexane.   The primer composition according to claim 1 or 2, wherein the polyol contains trimethylolpropane.   The primer composition according to any one of claims 1 to 3, wherein the isocyanate having an isocyanurate ring contains an isocyanurate body of hexamethylene diisocyanate and / or an isocyanurate body of isophorone diisocyanate.   The primer composition according to any one of claims 1 to 4, wherein the reactant (B) is contained in an amount of 5 to 500 parts by weight with respect to 100 parts by weight of the reactant (A).   The epoxysilane compound (C) contains at least one selected from the group consisting of γ-glycidoxypropylmethyldiethoxysilane, γ-glycidoxypropyltrimethoxysilane, and γ-glycidoxypropyltriethoxysilane. The primer composition according to any one of claims 1 to 5, wherein:   The primer composition according to any one of claims 1 to 6, comprising 5 to 50 parts by weight of the epoxysilane compound (C) with respect to 100 parts by weight of the reactant (A).