KR102387721B1 - Primer composition - Google Patents

Abstract

The present invention provides a primer composition that is excellent in various durability and exhibits good adhesion to various adherends in a short time after construction, and has high storage stability. The primer composition of the present invention is an acrylic copolymer obtained by copolymerizing a monomer component comprising (A) (A1) a (meth)acrylic acid ester containing an alkoxysilyl group and (A2) a (meth)acrylic acid ester not containing an alkoxysilyl group. and (B) the titanium compound represented by formula (1), and (C) a solvent, (A) relative to 100 parts by mass of the acrylic copolymer, (B) 0.3 to 10 parts by mass of the titanium compound, and ( C) The solvent is 100-5000 mass parts.
Ti(iC ₃ H ₇ O) _a (C ₅ H ₇ O ₂ ) _b (C ₆ H ₉ O ₃ ) _c (1)
(a, b and c are any integers from 0 to 4, provided that a+b+c=4)

Description

Primer composition {PRIMER COMPOSITION}

The present invention relates to a primer composition useful for adhesion between a room temperature curable organopolysiloxane composition and various types of adherends, and to a primer composition characterized in that the time until adhesion is obtained is short and storage stability is excellent.

In adhesion between room temperature curable organopolysiloxane compositions used as sealing materials for construction, general industrial sealing materials, and adhesives and various types of adherends, "silane-based primers" containing a silane coupling agent, titanate esters and solvents as main components, poly "A urethane primer" containing an isocyanate compound as a main component, a silane-modified acrylic resin, an "acrylic primer" containing a solvent as a main component, etc. have been used (refer patent documents 1 - 4).

As a silane coupling agent for a silane-based primer, one having an amino group, an epoxy group, a mercapto group, or an isocyanate group is generally used. Moreover, as a polyisocyanate compound of a urethane type primer, what is obtained by addition reaction of an isocyanate compound and polyols, such as polyethyleneglycol, is known.

The silane-based primer is useful for an inorganic adherend such as metal or glass, and has good heat resistance, weather resistance and durability. However, it is often seen that silane-based primers do not obtain sufficient adhesion to organic-based adherends such as various resins. One acrylic electrodeposition coating was insufficient in adhesion to aluminum or a fluororesin coating in which aluminum was coated with a coating containing a fluororesin as a main component.

On the other hand, the urethane-based primer has satisfactory adhesion to a wide range of adherends including metallic and organic adherends, but due to the characteristics of the urethane resin, it lacks durability such as heat resistance, weather resistance, and water resistance Therefore, it was not suitable for the use of a silicone curable composition requiring long-term durability. Moreover, also when using the blend primer of a silane type and a polyisocyanate type, it was difficult to make adhesiveness and durability compatible.

By the way, many silane-based or acrylic-based primers are used in silicone-based curable compositions. An acryl-type primer has the acrylic resin and solvent which have an alkoxysilyl group as main components. As such acrylic primers, many commercially available ones in which room temperature curable organopolysiloxane compositions exhibit good adhesion to various resins such as acrylic resins and polystyrene resins, which are difficult to adhere without a primer, are commercially available. Among these, there are some which adhere well to acrylic electrodeposition-coated aluminum and fluororesin-coated aluminum, and have higher heat resistance, weather resistance and water resistance than urethane primers. In this regard, the acrylic primer has been suitably used as a primer for a resin coated surface, a metal coated surface, or the like.

Japanese Patent Publication No. 53-005043 Japanese Patent No. 2522856 Publication Japanese Patent Laid-Open No. 4-224879 Japanese Patent Laid-Open No. 8-295852

However, in an acrylic primer with good adhesion, the adhesion between the room temperature curable organopolysiloxane composition (room temperature curable silicone rubber composition) and the adhesive strength are delayed. There was a problem that peeling occurred when a force was applied or applied.

Therefore, in recent years, in various industrial fields, it is essential to shorten the bonding process time by the room temperature curable silicone rubber composition in order to increase production efficiency. Development of a primer capable of expressing adhesiveness has been desired. Moreover, a primer composition with high storage stability in which adhesiveness does not fall also with long-term storage is calculated|required.

Accordingly, an object of the present invention is to provide a primer composition that is excellent in various durability and exhibits good adhesion to various adherends in a short time after construction, and has high storage stability.

As a result of repeated studies on the primer composition according to the present invention, the present inventors can solve the above problems by mixing an acrylic copolymer having a specific structure and a titanium compound having a specific structure in the primer composition in a predetermined ratio discovered and came to the present invention.

That is, the present invention

(1) A cured product of a room temperature curable organopolysiloxane composition (typically a condensation reaction curing type room temperature curable silicone rubber composition) and an organic resin, metal, and a coated metal surface (e.g., acrylic resin or fluororesin as main components) A primer composition for improving adhesion to a substrate selected from (a metal surface such as aluminum coated with a coating material), (A) (A1) (meth)acrylic acid ester containing an alkoxysilyl group, 100 parts by mass of an acrylic copolymer obtained by copolymerizing a monomer component containing no (meth)acrylic acid ester, (B) 0.3 to 10 parts by mass of a titanium compound represented by Formula (1), and (C) 100 to 100 parts by mass of a solvent A primer composition comprising at least 5000 parts by mass.

Ti(iC ₃ H ₇ O) _a (C ₅ H ₇ O ₂ ) _b (C ₆ H ₉ O ₃ ) _c (1)

(a, b and c are any integers from 0 to 4, provided that a+b+c=4)

(2) said (A) component makes 100 mass % of the whole monomer component of the said (A) component, (A1) 1-20 mass % of at least 1 type of (meth)acrylic acid ester containing an alkoxysilyl group, ( A2) The primer composition according to (1), characterized in that it is an acrylic copolymer obtained by copolymerizing a monomer component containing 50 to 99 mass of at least one (meth)acrylic acid ester not containing an alkoxysilyl group.

(3) When the whole monomer component of the said (A) component is 100 mass %, the ratio of (A1) at least 1 type of (meth)acrylic acid ester containing an alkoxysilyl group is 1-10 mass %, It is characterized by the above-mentioned The primer composition according to (2).

(4) When the whole monomer component of the said (A) component is 100 mass %, the ratio of at least 1 type of (meth)acrylic acid ester which does not contain the said (A2) alkoxysilyl group is 50 mass % or more and 99 mass % The primer composition according to (2) or (3), characterized in that it is less than.

(5) The component (B) contains (B1) titanium tetraalkoxide and/or an alkoxy group-containing titanium chelate compound, (B2) acetylacetone, (B2) acetylacetone 0.8 per mole of alkoxy group in (B1) The primer composition according to any one of (1) to (4), characterized in that it is produced by mixing in a ratio of moles or more but less than 2.0 moles.

(6) (D) 1-100 mass parts of alkyltrialkoxysilanes are further included, The primer composition in any one of (1)-(5) characterized by the above-mentioned.

(7) The primer composition according to any one of (1) to (6), wherein the titanium compound of the component (B) is a compound of an integer such that a=2 and b+c=2 in the formula (1).

ADVANTAGE OF THE INVENTION According to this invention, with respect to various to-be-adhered bodies, such as acrylic electrodeposition-coated aluminum and fluororesin-coated aluminum, it can provide the primer composition which shows favorable adhesiveness in a short period of time after construction, and is excellent also in various durability and storage stability.

Hereinafter, the present invention will be described in more detail. In addition, this invention is not limited by the following embodiment, What was comprised combining each following component suitably is also included in this invention. In addition, in this specification, (meth)acrylic acid means acrylic acid and/or methacrylic acid, and it is the same also about another compound.

The primer composition of the present invention is

(A) an acrylic copolymer containing an alkoxysilyl group (that is, (A1) a (meth)acrylic acid ester containing an alkoxysilyl group, and (A2) copolymerizing a monomer component containing a (meth)acrylic acid ester containing no alkoxysilyl group an acrylic copolymer obtained by

(B) a titanium compound represented by formula (1);

Ti(iC ₃ H ₇ O) _a (C ₅ H ₇ O ₂ ) _b (C ₆ H ₉ O ₃ ) _c (1)

(a, b and c are any integers from 0 to 4, provided that a+b+c=4)

(C) solvent

Including, (B) 0.3-10 mass parts of titanium compounds, and (C) solvent is 100-5000 mass parts with respect to 100 mass parts of (A) acrylic copolymers.

Hereinafter, each component contained in the primer composition of this invention is demonstrated in detail.

<(A) acrylic copolymer>

(A) The alkoxysilyl group-containing acrylic copolymer of component is a component used as a main component of the primer composition of this invention after drying, and becomes a component which determines the adhesiveness between a base material and a primer composition.

The acrylic copolymer contained in the primer composition of the present invention contains at least one (meth)acrylic acid ester containing an alkoxysilyl group in its molecule (hereinafter referred to as an alkoxysilyl group-containing component (A1)), and an alkoxysilyl group in the molecule. It copolymerizes the monomer component containing at least 1 type of (meth)acrylic acid ester which does not contain (henceforth an alkoxysilyl group non-containing component (A2)). In the present invention, (meth)acrylic acid refers to methacrylic acid or acrylic acid, or a mixture (mixed acid) thereof. Similarly, (meth)acrylic acid ester means methacrylic acid ester, acrylic acid ester, or a mixture (mixed ester) of these. In addition, (meth)acrylate means a methacrylate or an acrylate, or a mixture thereof.

Although it does not specifically limit about the polymerization reaction method of copolymerizing said monomer component, Radical polymerization, cationic polymerization, anionic polymerization, etc. are mentioned. Among them, random radical polymerization using an organic peroxide or an organic azo compound as an initiator is effective as a simple method.

[Alkoxysilyl group-containing component (A1)]

This alkoxysilyl group containing component (A1) is a monomer component containing at least 1 sort(s) of the (meth)acrylic acid ester containing an alkoxysilyl group in a molecule|numerator. In this monomer, the (meth)acrylic acid ester (A1) containing an alkoxysilyl group can be used 1 type or in combination of 2 or more type. Moreover, the (meth)acrylic acid ester (A1) containing an alkoxysilyl group is at least 1, Preferably it has 2 or 3 alkoxysilyl groups in 1 molecule.

Content of this alkoxysilyl group containing component (A1) is 1-20 mass %, when the whole monomer component of (A) component is 100 mass %, Preferably it is 1-15 mass %, More preferably is 1 to 10 mass %. Moreover, in this invention, it is preferable to contain the methacrylic acid ester containing an alkoxysilyl group as a component (A1), and it is 1-10 of the whole monomer components of (A) component especially the methacrylic acid ester containing an alkoxysilyl group. It is most preferable to contain mass %. When content of (A1) component is less than 1 mass % of the whole monomer component of (A) component, adhesion|attachment expression property is not acquired. Moreover, when there is more content of (A1) component than 20 mass % of the whole monomer component of (A) component, the adhesiveness to a to-be-adhered body falls.

Here, as (meth)acrylic acid ester containing an alkoxysilyl group in a molecule|numerator, 3-(meth)acryloxypropyl trimethoxysilane, 3-(meth)acryloxypropyl triethoxysilane, 3-(meth) acryloxypropylmethyldimethoxysilane and 3-(meth)acryloxypropylmethyldiethoxysilane are mentioned. Especially preferably, 3-(meth)acryloxypropyl trimethoxysilane is mentioned.

[Alkoxysilyl group-free component (A2)]

This alkoxysilyl group-free component (A2) is a monomer component containing at least 1 sort(s) of (meth)acrylic acid ester which does not contain an alkoxysilyl group in a molecule|numerator. In this monomer, the (meth)acrylic acid ester (A2) which does not contain an alkoxysilyl group can be used 1 type or in combination of 2 or more type.

Content of this alkoxysilyl group non-containing component (A2) is 50 or more and less than 99 mass %, when the whole monomer component in (A) component is 100 mass %, Preferably it is 70 mass % or more and less than 99 mass %. and more preferably 80 mass % or more and less than 99 mass %. When it deviates from this range, the adhesiveness to a to-be-adhered body will fall. Moreover, in this invention, it is preferable to contain the methacrylic acid ester which does not contain an alkoxysilyl group as a component (A2).

Examples of (meth)acrylic acid esters that do not contain an alkoxysilyl group in the molecule include aliphatic hydrocarbon esters of (meth)acrylic acid, alicyclic hydrocarbon esters of (meth)acrylic acid, aromatic hydrocarbon esters of (meth)acrylic acid, and ether bonds. and esters of alcohols to be used and (meth)acrylic acid.

As an aliphatic hydrocarbon ester of (meth)acrylic acid, For example, methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth) Acrylate, isobutyl (meth) acrylate, tert-butyl (meth) acrylate, n-pentyl (meth) acrylate, n-hexyl (meth) acrylate, n-heptyl (meth) acrylate, n-octyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, nonyl (meth) acrylate, isononyl (meth) acrylate, decyl (meth) acrylate, dodecyl meth (meth) arylate, stearyl ( meth) acrylate.

As alicyclic hydrocarbon ester of (meth)acrylic acid, cyclohexyl (meth)acrylate and isobornyl (meth)acrylate are mentioned, for example.

As aromatic hydrocarbon ester of (meth)acrylic acid, phenyl (meth)acrylate, benzyl (meth)acrylate, and toluyl meth (meth)arylate are mentioned, for example.

As ester of alcohol containing an ether bond, and (meth)acrylic acid, For example, Alkoxyalkyl (meth)acrylates, such as 2-methoxyethyl (meth)acrylate and 2-methoxybutyl (meth)acrylate; Epoxy group-containing (meth)acrylates, such as glycidyl (meth)acrylate and methylglycidyl (meth)acrylate, are mentioned.

The (meth)acrylic acid ester not containing an alkoxysilyl group is preferably an aliphatic hydrocarbon ester of (meth)acrylic acid, more preferably a (meth)acrylic acid alkyl ester having an alkyl group having 1 to 20 carbon atoms, further Preferably, it is a (meth)acrylic-acid alkylester which has a C1-C10 alkyl group. Especially preferably, methyl (meth)acrylate, ethyl (meth)acrylate, n-butyl (meth)acrylate, and tert-butyl (meth)acrylate are mentioned. Moreover, in this invention, when the whole monomer component is 100 mass %, it is especially preferable to contain 30 mass % or more and less than 99 mass % of methyl (meth)acrylate. It is most preferable to contain 30 mass % or more and less than 99 mass % of methyl methacrylate.

[Other Ingredients]

(A) The acrylic copolymer may contain other monomer components other than the alkoxysilyl group-containing component (A1) and the alkoxysilyl group-free component (A2). As other monomer components, N,N-dimethylacrylamide, N-methylol (meth)acrylamide, N-vinylpyrrolidone, vinyl propionate, vinyl stearate, vinyl chloride, vinylidene chloride, vinyl acetate, styrene, etc.; Vinyl-type monomers other than an acryl-type monomer, etc. are mentioned. When this other monomer component makes the whole monomer component of (A) component 100 mass %, it is 49 mass % or less, Preferably it is 20 mass % or less, More preferably, it is 0 mass %.

<(B) Titanium compound>

(B) The titanium compound of the component is an organic titanium compound represented by the following formula (1),

Ti(iC ₃ H ₇ O) _a (C ₅ H ₇ O ₂ ) _b (C ₆ H ₉ O ₃ ) _c (1)

(a, b and c are any integers from 0 to 4, provided that a+b+c=4)

At least one of acetylacetonate (C ₅ H ₇ O ₂ ), isopropoxide (iC ₃ H ₇ O) and ethylacetoacetate (C ₆ H ₉ O ₃ ) is contained. Preferably, it contains at least one of acetylacetonate (C ₅ H ₇ O ₂ ) and isopropoxide (iC ₃ H ₇ O) (ie, in Formula (1), 1≤a+b≤ 4), more preferably only acetylacetonate (C ₅ H ₇ O ₂ ) (ie, b=4 in formula (1)).

Moreover, in said Formula (1), although a, b and c are each an integer in any one of 0-4, and also satisfy|fill a+b+c=4, a, b, and c are suitably 0, 2 or 4 respectively, in particular a=0, b=4, c=0 combination, a=2, b=2, c=0 combination, a=4, b=0, c=0 combination , a=2, b=0, c=2 combination, a=0, b=0, c=4 combination, a=0, b=2, c=2 combination, and the like.

This component (B) plays a role as an adhesion promoter which improves the adhesiveness to the base material of the primer composition of this invention, and shortens the time for the adhesiveness of a curable composition and a primer composition to express.

(B) The compounding quantity of component is 0.3-10 mass parts with respect to 100 mass parts of (A) component. Preferably it is 0.3-5 mass parts, More preferably, it is 0.4-3 mass parts, More preferably, it is 0.45-2.5 mass parts. If it is less than 0.3 mass part, adhesive expression becomes slow and desired adhesiveness cannot be acquired in a short time. In addition, when it exceeds 10 parts by mass, the storage stability of the primer composition is lowered, the adhesion of the primer composition to various substrates after long period of manufacture cannot be obtained, and the cured product of the constructed curable composition is transferred from the substrate to the primer. It peels off with a composition in many cases.

As a commercial item containing such a titanium tetraacetylacetonate compound, For example, Orgatyx TC-401 (made by Matsumoto Fine Chemical Co., Ltd.) (a=0, b=4, c=0 in Formula (1)) Represented Ti(C ₅ H ₇ O ₂ ) ₄ isopropyl alcohol solution containing 65 mass % of titanium tetraacetylacetonate compound), Orgatyx TC-100 (manufactured by Matsumoto Fine Chemicals Co., Ltd.) (Formula (1) ) in Ti(iC ₃ H ₇ O) ₂ (C ₅ H ₇ O ₂ ) ₂ represented by a = 2, b = 2, c = 0 of titanium diisopropoxybis (acetylacetonate) compound 75 Isopropyl alcohol solution containing mass%), Orgatyx TA-10 (manufactured by Matsumoto Fine Chemical Co., Ltd.) (Ti(iC ₃ ) represented by a=4, b=0, c=0 in formula (1) 99% by mass of the titanium tetraisopropoxide compound of H ₇ O) ₄ ), Orgatyx TC-750 (manufactured by Matsumoto Fine Chemicals, Ltd.) (a = 2, b = 0, c in the formula (1)) =2 isopropyl alcohol solution containing 95 mass % of titanium diisopropoxybis (ethylacetoacetate) compound of Ti(iC ₃ H ₇ O) ₂ (C ₆ H ₉ O ₃ ) ₂ represented by =2); there is. Among them, Orgatyx TC-401 is suitable from the viewpoint of adhesiveness.

(B) As a component, an alkyl titanate and/or an alkoxy group-containing titanium chelate compound and acetylacetone are mixed with acetylacetone in a ratio of 0.8 mol or more and less than 2.0 mol with respect to 1 mol of titanium atoms in the titanium-containing compound. you can use that When using the component (B) prepared in this way, it may be mixed in advance before preparation of the primer composition of the present invention, or may be added separately when preparing the primer composition of the present invention, and may be mixed in the primer composition.

In addition, component (B) is prepared by mixing titanium tetraalkoxide and/or an alkoxy group-containing titanium chelate compound with acetylacetone, and 0.8 mol or more and less than 2.0 mol of acetylacetone with respect to 1 mol of alkoxy group in the titanium-containing compound You may.

<(C) Solvent>

The solvent of the component (C) is used by dissolving or dispersing the component (A) and the component (B) to facilitate the coating operation and impart quick-drying properties. (C) The kind of solvent of component is not particularly limited as long as the primer composition does not lose transparency or uniformity, but is selected according to the solvent resistance of the target adherend, brush working conditions, and the like.

Such a solvent is a good solvent for component (A), and ketones, such as acetone and methyl ethyl ketone, esters, such as ethyl acetate and butyl acetate, aromatic hydrocarbons, such as toluene and xylene, are mentioned. Moreover, you may use alcohol and aliphatic hydrocarbons as a poor solvent of (A) component. As an example of alcohol, methanol, ethanol, isopropyl alcohol, and 2-ethyl-1- hexanol are mentioned, for example. Examples of the aliphatic hydrocarbons include n-hexane, n-heptane, and isooctane (2,2,4-trimethylpentane).

(C) The compounding quantity of component is 100-5000 mass parts with respect to 100 mass parts of (A) component, Preferably it is 200-3000 mass parts, More preferably, it is 300-1000 mass parts. (C) When the compounding amount of the component is less than 100 parts by mass, the film thickness of the alkoxysilyl group-containing acrylic copolymer remaining on the surface of the substrate after coating and drying the primer composition becomes too thick, so that it not only easily peels off from the substrate, When the usage fee of an acrylic copolymer increases, it becomes disadvantageous also in terms of cost. On the other hand, when the compounding quantity of (C)component exceeds 5000 mass parts, the layer of the primer composition after drying will become thin too much, and the effect|action which improves adhesiveness will be lost.

<(D) Additives>

(D) As an additive of component, in order to improve the storage stability of the primer composition of this invention, etc., you may contain alkyltrialkoxysilane, acetylacetone, etc. as an arbitrary component as needed. (D) Among the components, examples of the alkyltrialkoxysilane include methyltrimethoxysilane, methyltriethoxysilane, ethyltrimethoxysilane, n-propyltrimethoxysilane, and vinyltrimethoxysilane. , especially, methyltrimethoxysilane and acetylacetone are preferable.

(D) The compounding quantity of component is 0.1-100 mass parts with respect to 100 mass parts of (A) component. Preferably it is 0.5-10 mass parts, More preferably, it is 1-5 mass parts. When it is less than 0.1 parts by mass, since the primer composition thickens during storage, the period until gelation becomes faster, and when it is more than 100 parts by mass, there is almost no disadvantage in terms of performance, but a disadvantage in cost occurs.

<Other additives>

Other optional components can be added to the primer composition of the present invention within a range that does not impair its performance. Examples of these components include organotin compounds such as dibutyltin dimethoxide, dibutyltin diacetate, dibutyltin dioctanoate and dibutyltin dilaurate as the silanol condensation catalyst; aluminum alkoxides such as aluminum acetylacetonate; zirconium alkoxides such as zirconium acetylacetonate; A silane coupling agent etc. are mentioned as an adhesion-imparting agent. These types and addition amounts are selected according to the use.

<Adhesive method using primer composition>

In order to adhesively cure a cured product of a room temperature curable organopolysiloxane composition (typically a condensation reaction curing type room temperature curable silicone rubber composition) to various substrates using the primer composition of the present invention, metals, painted metals (e.g., acrylic water The primer composition of the present invention is applied with a brush or the like to the surface of various substrates such as aluminum, etc.) or an organic resin, etc. coated with a paint containing a fluororesin as the main component, dried, and then the curable composition is brought into contact with the coated surface. harden

In normal temperature (25 degreeC), the range of 5 minutes - 480 minutes is preferable, and, as for the drying time of the primer composition after application|coating, 10 minutes - 120 minutes are more preferable. When the drying time is shorter than 5 minutes, drying of the solvent is insufficient and the strength of the primer layer after drying is not obtained. In addition, when the drying time exceeds 480 minutes, there is a possibility that contaminants such as dust or dust in the air will adhere to the surface, which may impair adhesion.

In addition, the primer composition of the present invention is effective as an adhesion imparting agent for adhering a cured product (silicone rubber) of a room temperature curable organopolysiloxane composition to various substrates, an adhesion improver and an adhesion development improver, but a room temperature curable organopolysiloxane In addition to the composition, it is also effective for a curable composition having a silyl group capable of forming a siloxane bond with the primer composition, for example, a modified silicone-based curable composition or a silylated polyurethane-based curable composition.

Example

Hereinafter, although an Example demonstrates this invention in detail, this invention is not limited by these.

<(A) Preparation of acrylic copolymer>

Based on the components shown in Table 1, each copolymer of Synthesis Examples 1 to 4 was produced by the following preparation method.

[Synthesis Example 1]

150.0 g of ethyl acetate and 150.0 g of isopropyl alcohol were put into a 5 L glass four-neck flask equipped with a reflux cooling tube, a rotary stirrer, a nitrogen introduction tube and a thermometer through which cooling water at 10 ° C. was passed, and mixed under nitrogen ventilation. Next, 20.0 g of methyl methacrylate, 20.0 g of n-butyl methacrylate, and 2.0 g of 3-trimethoxysilyl propyl methacrylate were added and mixed, and the temperature of the mixed solution in the flask was adjusted to 80 using an oil bath. It was heated to ℃. Subsequently, 1.5 g of 2,2'-azobis(2-methylbutyronitrile) was added, mixed, and dissolved. A mixture of 60.0 g of methyl methacrylate, 60.0 g of n-butyl methacrylate, and 6.0 g of 3-trimethoxysilyl propyl methacrylate was put into the dropping funnel, and it was added dropwise into the flask over 2 hours. At this time, the temperature of the solution in the flask was adjusted to be 75°C to 80°C. After completion of the dropwise addition, the mixture was further aged at 80°C for 2 hours, then heating with an oil bath was terminated, and the mixture was cooled to 40°C. After cooling, 200.0 g of ethyl acetate and 300.0 g of isopropyl alcohol were added, mixed until uniform, and a colorless and transparent acrylic copolymer solution was synthesized.

[Synthesis Example 2]

150.0 g of ethyl acetate and 150.0 g of isopropyl alcohol were put into a 5 L glass four-neck flask equipped with a reflux cooling tube, a rotary stirrer, a nitrogen introduction tube and a thermometer through which cooling water at 10 ° C. was passed, and mixed under nitrogen ventilation. Next, 40.0 g of methyl methacrylate and 2.0 g of 3-trimethoxysilyl propyl methacrylate were added and mixed, and the temperature of the mixed solution in the flask was heated to 80°C using an oil bath. Subsequently, 1.5 g of 2,2'-azobis(2-methylbutyronitrile) was added, mixed, and dissolved. A liquid mixture of 120.0 g of methyl methacrylate and 6.0 g of 3-trimethoxysilyl propyl methacrylate was put into the dropping funnel, and it was added dropwise in the flask over 2 hours. At this time, the temperature of the solution in the flask was adjusted to be 75°C to 80°C. After completion of the dropwise addition, the mixture was further aged at 80°C for 2 hours, then heating with an oil bath was terminated, and the mixture was cooled to 40°C. After cooling, 200.0 g of ethyl acetate and 300.0 g of isopropyl alcohol were added, mixed until uniform, and a colorless and transparent acrylic copolymer solution was synthesized.

[Synthesis Example 3] (Comparative Synthesis Example)

150.0 g of ethyl acetate and 150.0 g of isopropyl alcohol were put into a 5 L glass four-neck flask equipped with a reflux cooling tube, a rotary stirrer, a nitrogen introduction tube and a thermometer through which cooling water at 10 ° C. was passed, and mixed under nitrogen ventilation. Next, 15.0 g of methyl methacrylate, 15.0 g of n-butyl methacrylate, and 12.0 g of 3-trimethoxysilyl propyl methacrylate were added and mixed, and the temperature of the mixed solution in the flask was adjusted to 80 using an oil bath. It was heated to ℃. Subsequently, 1.5 g of 2,2'-azobis(2-methylbutyronitrile) was added, mixed, and dissolved. A mixture of 45.0 g of methyl methacrylate, 45.0 g of n-butyl methacrylate, and 36.0 g of 3-trimethoxysilyl propyl methacrylate was put into the dropping funnel, and it was added dropwise in the flask over 2 hours. At this time, the temperature of the solution in the flask was adjusted to be 75°C to 80°C. After completion of the dropwise addition, the mixture was further aged at 80°C for 2 hours, then heating with an oil bath was terminated, and the mixture was cooled to 40°C. After cooling, 200.0 g of ethyl acetate and 300.0 g of isopropyl alcohol were added, mixed until uniform, and a colorless and transparent acrylic copolymer solution was synthesized.

[Synthesis Example 4] (Comparative Synthesis Example)

A colorless and transparent acrylic copolymer solution was synthesized in the same manner as in Synthesis Example 3 except that n-butyl methacrylate was changed to tert-butyl methacrylate.

<Examples and Comparative Examples>

Based on the components shown in Table 2, Examples 1 to 7 and Comparative Examples 1 to 3 were produced by the following method.

[Example 1]

To 577 parts by mass of the acrylic copolymer solution obtained in Synthesis Example 1 (including 100 parts by mass of the acrylic copolymer of component (A), 208 parts by mass of ethyl acetate, and 268 parts by mass of isopropyl alcohol), 40 parts by mass of ethyl acetate, isopropyl 30 parts by mass of alcohol, 4.8 parts by mass of 2-ethyl-1-hexanol, 40 parts by mass of isooctane, and 2.0 parts by mass of methyltrimethoxysilane are added, followed by titanium tetraacetylacetonate containing 65% by mass of titanium tetraacetylacetonate A light yellow transparent primer by adding 1.2 parts by mass of an isopropyl alcohol solution of nate (Matsumoto Fine Chemical Co., Ltd., Orgatyx TC-401) (that is, 0.78 parts by mass in terms of mass of titanium tetraacetylacetonate) and mixing A composition was obtained.

[Example 2]

Diisopro instead of 1.2 parts by mass of an isopropyl alcohol solution of titanium tetraacetylacetonate containing 65% by mass of titanium tetraacetylacetonate of Example 1 (Matsumoto Fine Chemical Co., Ltd., Orgatyx TC-401) 0.84 parts by mass of an isopropyl alcohol solution of diisopropoxytitanium bis(acetylacetonate) (Matsumoto Fine Chemicals, Ltd., Orgatyx TC-100) containing 75% by mass of titanium bis(acetylacetonate) ( That is, a pale yellow transparent primer composition was obtained by adding 0.63 mass parts by mass of diisopropoxytitanium bis(acetylacetonate) and 0.36 mass parts of acetylacetone.

[Example 3]

Instead of 1.2 mass parts of isopropyl alcohol solution of titanium tetraacetylacetonate containing 65 mass % of titanium tetraacetylacetonate of Example 1 (Matsumoto Fine Chemical Co., Ltd. make, Orgatyx TC-401), tetraisopropyl 0.48 parts by mass of titanate (99% by mass of active ingredient, manufactured by Matsumoto Fine Chemicals, Ltd., Orgatyx TA-10) (that is, 0.48 parts by mass in terms of mass of tetraisopropyl titanate) and 0.72 parts by mass of acetylacetone were added By doing so, a pale yellow transparent primer composition was obtained.

[Example 4]

In Example 1, a primer composition was obtained in the same manner as in Example 1 except that the acrylic copolymer solution of Synthesis Example 2 was used instead of the acrylic copolymer solution of Synthesis Example 1.

[Example 5]

Diisopro instead of 1.2 parts by mass of an isopropyl alcohol solution of titanium tetraacetylacetonate containing 65% by mass of titanium tetraacetylacetonate of Example 1 (Matsumoto Fine Chemical Co., Ltd., Orgatyx TC-401) Mass of 1.2 parts by mass (that is, diisopropoxytitanium bis(ethylacetoacetate)) (95 mass % or more of active ingredient, Orgatyx TC-750, manufactured by Matsumoto Fine Chemical Co., Ltd.) In conversion, it carried out similarly to Example 1 except adding 1.14 mass parts - 1.2 mass parts), and the pale yellow transparent primer composition was obtained.

[Example 6]

Except not having added 0.36 mass parts of acetylacetone, it carried out similarly to Example 2, and obtained the primer composition.

[Example 7]

Except not having added 0.72 mass parts of acetylacetone, it carried out similarly to Example 3, and obtained the primer composition.

[Comparative Example 1]

It is the same as Example 1 except not having added 1.2 mass parts of isopropyl alcohol solutions of titanium tetraacetylacetonate containing 65 mass % of titanium tetraacetylacetonate (Matsumoto Fine Chemical Co., Ltd. make, Orgatyx TC-401) and a primer composition was obtained.

[Comparative Example 2]

In Example 1, a primer composition was obtained in the same manner as in Example 1 except that the acrylic copolymer solution of Synthesis Example 3 (comparative synthesis example) was used instead of the acrylic copolymer solution of Synthesis Example 1.

[Comparative Example 3]

In Example 1, a primer composition was obtained in the same manner as in Example 1 except that the acrylic copolymer solution of Synthesis Example 4 (comparative synthesis example) was used instead of the acrylic copolymer solution of Synthesis Example 1.

<Evaluation of adhesion>

About each primer composition obtained in Examples 1-7 and Comparative Examples 1-3, the adhesiveness with respect to an aluminum blackboard was evaluated by the following method.

[Preparation of test pieces]

Each primer composition was applied to an acrylic electrodeposition-coated aluminum plate with a brush, and left for 30 minutes under the conditions of 23° C. and 50% relative humidity (RH), followed by an alcohol-free two-component silicone-based sealing material (SEALANT-FC-295SG: A mixture of a main ingredient and a curing agent manufactured by Shin-Etsu Chemical Co., Ltd.) was applied to the coated surface of an aluminum plate coated with each primer composition, and was applied with a spatula in a shape of 10 mm width, 50 mm length, and 2 mm thickness. It was shape|molded and it was set as the test piece.

[Adhesive test]

After this test piece is cured under the following conditions, the cured product of the silicone-based sealing material is cut with a knife, the cut portion is peeled by hand (pick up and pulled by hand), and the peeling state is observed (hand peel test by knife cut) By doing so, the state of the adhesive interface of a to-be-adhered body and a primer composition was evaluated.

[Adhesive Appearance]

About adhesion development, after curing for 4 hours in the environment of temperature 23 degreeC and 50% of relative humidity, the hand peeling test by the said knife cut evaluated. Evaluation was "(circle)" that the ratio of the area in which the cohesive failure of the sealing material was 100% was "(circle)", what was 80% or more of copper and less than 100% "(circle)", what was 50% or more of copper and less than 80%, "Δ", and less than 50% of copper It was made into "x". Table 3 shows the test results of adhesion development in the case of using each primer composition. In addition, the copper silicone-based sealing material is a fast-setting sealing material that is cured and rubberized after 1 hour by mixing a main agent and a curing agent.

[Initial Adhesion]

About initial stage adhesiveness, after curing for 7 days in the environment of temperature 23 degreeC and 50% of relative humidity, the method similar to the test method of adhesion development property evaluated. Table 3 shows the test results of initial adhesion when using each primer composition.

[Water-resistant adhesiveness]

About water-resistant adhesiveness, after curing for 7 days in the environment of temperature 23 degreeC and 50% of relative humidity, after immersing in 50 degreeC warm water for 7 days, the method similar to the test method of adhesion development property evaluated. Table 3 shows the test results of water-resistance adhesion in the case of using each primer composition.

<Evaluation of storage stability>

About each primer composition obtained in Examples 1-4, the following method evaluated storage stability.

[Storage Stability]

Each of the obtained primer compositions was sealed in a glass bottle, left still for 28 days in a dryer adjusted to 50 ° C., and taken out, cooled by air and returned to 23 ° C. Adhesiveness), the state of the adhesive interface between the adherend and the primer composition was evaluated under the same conditions and methods.

The result of the above (adhesion development to acrylic electrodeposition coating aluminum, initial adhesion, water-resistant adhesion) test results and all tests were the same, or when the ratio of cohesive failure increased, "○", cohesive failure in either test When the ratio of was decreased, it was set as "x". Table 4 shows the test results of storage stability. Thereby, it can be verified whether the performance can be exhibited even when a primer composition is used after long-term storage in an unused state.

It turned out that the composition of this invention has good adhesiveness with respect to various to-be-adhered bodies used for a building sealing material, and is excellent also in storage stability, as shown in an Example.

INDUSTRIAL APPLICABILITY The present invention can be suitably used for bonding between a room temperature curable organopolysiloxane composition used as a sealing material for construction, a sealing material for general industrial use, and an adhesive, and various types of adherends.

Claims (8)

A primer composition for improving adhesion between a cured product of a room temperature curable organopolysiloxane composition and a substrate selected from an organic resin, a metal, and a coated metal surface, the primer composition comprising:
(A) (A1) contains (meth)acrylic acid ester containing an alkoxysilyl group, and (A2) (meth)acrylic acid ester containing no alkoxysilyl group;
(A1) 1-10 mass % of (meth)acrylic acid ester containing an alkoxysilyl group, and (A2) (meth)acrylic acid ester which does not contain an alkoxysilyl group by 100 mass % of the whole monomer component of this (A) component. 100 parts by mass of an acrylic copolymer composed of a copolymer of a monomer component containing 80 to 99% by mass;
(B) 0.3 to 10 parts by mass of the titanium compound represented by the formula (1),
Ti(iC ₃ H ₇ O) _a (C ₅ H ₇ O ₂ ) _b (C ₆ H ₉ O ₃ ) _c (1)
(a, b and c are any integers from 0 to 4, provided that a+b+c=4)
(C) Solvent 100-5000 parts by mass
A primer composition comprising at least a. The (meth)acrylic acid ester containing the alkoxysilyl group of the component (A1) and the alkoxysilyl group of the component (A2) according to claim 1, wherein the total amount of the acrylic copolymer of the component (A) is 100% by mass. Other than (meth)acrylic acid ester not contained is 0 mass % of other monomer components, The primer composition characterized by the above-mentioned. The ratio of at least 1 type of (meth)acrylic acid ester which does not contain the said (A2) alkoxysilyl group according to claim 1, wherein when the total amount of the monomer component of the component (A) is 100% by mass, 80% by mass or more. It is less than 99 mass %, The primer composition characterized by the above-mentioned. The ratio of at least one type of (meth)acrylic acid ester which does not contain the said (A2) alkoxysilyl group according to Claim 2, when the whole monomer component of the said (A) component is 100 mass % 80 mass % or more It is less than 99 mass %, The primer composition characterized by the above-mentioned. The compound (B1) according to any one of claims 1 to 4, wherein the component (B) is a mixture of (B1) a titanium tetraalkoxide and/or an alkoxy group-containing titanium chelate compound and (B2) acetylacetone, (B1) A primer composition characterized in that the ratio of (B2) acetylacetone to 1 mol of the alkoxy group in the titanium compound is 0.8 mol or more and less than 2.0 mol. The primer composition according to any one of claims 1 to 4, further comprising 1 to 100 parts by mass of (D) alkyltrialkoxysilane. The primer composition according to any one of claims 1 to 4, wherein the titanium compound of the component (B) is an integer compound such that a=2 and b+c=2 in the formula (1). delete