JPH0660302B2 - Adhesive composition - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an adhesive composition, and particularly to an adhesive composition for laminating a polyvinyl fluoride film with a hot-dip galvanized steel sheet and an aluminum sheet, which has excellent rust prevention properties. It is about things.

(Prior Art) In recent years, a laminate of a polyvinyl fluoride film having excellent weather resistance, abrasion resistance and solvent resistance has attracted attention as a material for wall boards and a material for roof boards. This polyvinyl fluoride film is sold by DuPont under the trade name Tedlar. This Tedlar is used as various building materials by forming it into a film or sheet and laminating it on a metal sheet. At this time, various characteristic conditions required for the adhesive must satisfy high adhesive strength, cohesive strength, hydrolysis stability, weather resistance, rust resistance and the like.

That is, if the adhesive does not have such characteristics, the film will peel off or the bonded portion will deteriorate, and a laminate that fully exhibits the characteristics of polyvinyl fluoride cannot be obtained. As an adhesive agent for Tedlar, DuPont's special patent 3
Those proposed in Japanese Patent Publication No. 8-18530, Japanese Patent Publication No. 38-26763, and Japanese Patent Publication No. 42-11918 are known. It is produced by copolymerizing several kinds of methacrylate ester and a monomer containing an epoxy group and reacting this polymer with gaseous ammonia or a primary monoamine. Therefore, this adhesive is made of an acrylic polymer having an amino group or an imino group in the side chain.

On the other hand, the surface of the Tedlar film to be adhered is subjected to a special surface treatment as described in JP-B-38-18530 and JP-B-42-11918.

As described in the above patent, it is said that an adhesive which is practically satisfactory is mainly composed of an acrylic polymer having an amino group or an imino group in the side chain.

(Problems to be Solved by the Invention) The above-mentioned acrylic polymer has, for example, the general formula (II) (Wherein Z is a hydrocarbon and R ₁ · R ₂ and R ₃ are alkyl groups or hydrogen) is a polymer having a group represented by reacting amines with a vinyl polymer containing glycidyl methacrylate or the like. It is obtained by reacting a vinyl polymer containing a carboxylic acid with an imine compound.

Since the main use of the laminated product of Tedlar film and hot-dip galvanized steel plate and aluminum plate is outdoors, it is more rustproof (e.g., in areas with hot and humid climates, temperature changes and salt damage near the coast. (There is a decrease in adhesive strength due to corrosion from the edges or scratches).
That is, the hot-dip galvanized steel plate and the aluminum plate must have excellent adhesion to the substrate, corrosion resistance, water resistance and the like.

The novel composition of the present invention has the above properties.

(Means for Solving Problems) The present invention comprises (A) methyl methacrylate, alkyl methacrylate, alkyl acrylate, or a mixture thereof as an adhesive for laminating a polyvinyl fluoride film and a hot-dip galvanized steel plate or an aluminum plate. Containing a polymer obtained by copolymerizing a monomer and an unsaturated carboxylic acid and then reacting with an alkyleneimine, (B) a dispersion of an anticorrosion pigment with an epoxy resin, and (C) a silane coupling agent as a binder The present invention relates to an adhesive composition characterized in that

According to the invention, 10-80% binder and 90-2
In an adhesive composition containing 0% by weight of an organic solvent, the binder component is selected from the group consisting of (a) methylmethacrylate, alkylmethacrylate having an alkyl group of 2 to 12 carbon atoms and alkylacrylate. A polymer obtained by polymerizing at least one essential monomer consisting of (meth) acrylate, the polymer having an amino ester group as a pendant group, and (b) an epoxy resin. 0.1 to 10% by weight of the silane coupling agent, based on the weight of the binder, and 0.1.
-40% by weight of anticorrosive pigment.

A particularly excellent point of the composition of the present invention is that it has superior adhesive strength, boiling water resistance and corrosion resistance as compared with conventional adhesive compositions for laminating polyvinyl fluoride films.

The polymer used in the present invention has methyl methacrylate, an alkyl group having 2 to 12 carbon atoms, preferably 2 to 8 alkyl methacrylate or an alkyl group having 2 to 12 carbon atoms,
Preferably, it is formed by polymerizing an essential monomer consisting of 2 to 8 alkyl acrylate or a mixture thereof, and has an amino ester group as a pendant group. The number average molecular weight of this polymer is about 1,500-10.
50,000, preferably about 10,000-50,000
Is.

The molecular weight is determined by gel permeation chromatography using polystyrene as a standard sample.

One method of making the acrylic polymer of the present invention is
(I) Copolymerizing a monomer consisting of methyl methacrylate, alkyl methacrylate, alkyl acrylate or a mixture thereof with (ii) a functional monomer of an unsaturated carboxylic acid such as methacrylic acid or acrylic acid, and then polymerizing the resulting polymer. It is a method of forming an aminoester group branched from a polymer skeleton as a pendant group by post-reacting a carboxyl group with an alkyleneimine.

The method for polymerizing monomers for producing a polymer is
A solvent and a polymerization initiator are put in a polymerization reaction container, and about 50 to
About 1 to 1 at a temperature of 200 ° C., preferably 60 to 100 ° C.
It is carried out by a commonly used method of producing a polymer by reacting for 5 hours, preferably for 8 to 13 hours.

Typical polymerization initiators used are azo polymerization initiators such as azobisisobutyronitrile and azobis (gamma-dimethylvaleronitrile), or benzoyl peroxide, cumyl peroxide, oxyneodecanoate, diisopropyl peroxide. Oxydicarbonate, t
-Peroxy polymerization initiators such as -butyl cumyl peroxide, cumene hydroperoxide, t-butyl hydroperoxide, cyclohexanone peroxide, methyl ethyl ketone peroxide, dicumyl peroxide, t-butyl hydroperoxide, lauroyl peroxide, etc. is there. The polymerization initiator is used in an amount of 0.01 to 2% by weight, preferably 0.1 to 1% by weight, based on the total amount of monomer components.

Typical solvents used are toluene, xylene,
Ethyl acetate, isopropyl acetate, acetone, methyl ethyl ketone, methyl isobutyl ketone, dioxane, tetrahydrofuran, cyclohexane, methanol, ethanol, isopropanol, cyclohexanol and other commonly used aliphatic, alicyclic, aromatic hydrocarbons, esters , Ethers, ketones and alcohols.

One preferred acrylic polymer is, for example, about 3
Containing 0-50 wt% methyl methacrylate, 1-25 wt% butyl acrylate, 30-50 wt% butyl methacrylate and 1-20 wt% methacrylic acid, branched from the carbon-carbon backbone of the resulting polymer. General formula (I) (However, in the formula, R represents an alkylene group having 2 to 3 carbon atoms) It is post-reacted with an alkyleneimine such as ethyleneimine and propyleneimine so that an amino ester pendant group is formed.

Examples of the monomer used for producing this polymer include (i) styrene, methyl methacrylate as an essential monomer, an alkyl methacrylate having 2 to 12 carbon atoms in the alkyl group, for example, ethyl methacrylate,
Alkyl acrylates having 2 to 12 carbon atoms in the alkyl group such as propyl methacrylate, isopropyl methacrylate, butyl methacrylate, isobutyl methacrylate, pentyl methacrylate, hexyl methacrylate, ethylhexyl methacrylate, nonyl methacrylate, decyl methacrylate, lauryl methacrylate, for example, ethyl acrylate, Propyl acrylate, isopropyl acrylate, butyl acrylate, isobutyl acrylate, pentyl acrylate, hexyl acrylate, ethylhexyl acrylate, nonyl acrylate, decyl acrylate, lauryl acrylate, etc. (ii) Acrylic acid and methacrylic acid are copolymerizable unsaturated carboxylic acids. It is also possible to use unsaturated carboxylic acid monomers having low reactivity such as itaconic acid, fumaric acid and maleic acid. It is also possible to use glycidyl-functional unsaturated monomers such as glycidyl acrylate or glycidyl methacrylate.

In addition to these monomers, vinyl oxazoline ester, maleic acid ester such as diethyl maleate, and fumarate ester such as dimethyl fumarate can be used as the monomer as long as the characteristics of the present invention are not impaired.

The polymer-forming monomers are selected to give the final finish consisting of the adhesive composition, the desired glass transition temperature and flexibility.

The epoxy resin that can be used in the present invention includes β
-Methyl epichloro type and novolak type are available. β-
Methylepichloro-type epoxy resin has the following general formula (II
I) (In the formula, n represents a positive integer of about 0.5 to 4). Preferably, the epoxy resin is the polymerization product of epichlorohydrin and bisphenol A.
When the preferred epoxy resin is used, R of the above formula is used.
Is general formula (IV) Has the structure

Representative of these preferred epoxy resins include about 185-1 of Shell Chemical Co.
92 equivalents of "Epon" 828 and Dow Chemical Co., about 182 to 190 equivalents of D.E. E. R. There is 331. Another representative is "Epon" 1001 with an equivalent weight of about 450-550. The "equivalent weight" here is 1
It is the number of grams of resin having a gram equivalent of epoxide.

As the novolac type epoxy resin, the following general formula V
(For example, Epon 1301 manufactured by Shell Chemical Co.).

As the rust preventive pigment which can be used in the present invention, those having a rust preventive power and those selected from the commonly known ones can be used.
Either can be used. Representative examples of these are various chromate compounds such as basic lead chromate, zinc chromate, strontium chromate, and barium chromate; various lead compounds such as calcium leadate, lead tin, and lead cyanamide; Various phosphate compounds such as zinc phosphate, ammonium tripolyphosphate, zinc phosphite and aluminum phosphomolybdate; various molybdate compounds such as basic zinc molybdate and calcium molybdate; barium metaborate, metaboric acid Various borate compounds such as calcium and calcium borosilicate; mica-like iron oxide (MIO), chemical formula MeOFe ₂ O
₃ (where Me is Ca, Sr, Ba, Mg, Z
Various iron oxide compounds such as magnetic ferrites represented by a divalent metal atom such as n or Mn; tungstate compounds and the like. Such antirust pigments can be used alone or as a mixture of two or more kinds. The amount of these rust-preventive pigments used is appropriately in the range of 0.1 to 40% by weight, and preferably 0.5 to less than 20% by weight, as described above. 0.1% by weight
If it is less than 40% by weight, the anticorrosiveness of the adhesive layer will be inferior, and if it exceeds 40% by weight, the water resistance and moisture resistance of the adhesive layer will be inferior. Further, it must be dispersible in the acrylic polymer or epoxy resin of the binder.

Further, in the step of continuously applying the composition of the present invention to a base material, a color pigment or a dye may be blended for the purpose of judging whether the coating state is good or bad. Ordinary inorganic pigments such as titanium oxide, yellow lead, titanium yellow, chromium oxide, etc. are selected from among known and commonly used dyes, and dyes are ordinary disperse dyes,
For example, Kayaset Yellow G, Kayaset Yellow 937, Kay
Commercially available products such as aset Yellow K-RL are used. Those having both coloring power and hiding power are more preferable. Further, it must be dispersible in the acrylic polymer or epoxy resin of the binder. Further, they may be used alone or in combination of two or more kinds. It may also serve the purpose of the above-mentioned rust preventive pigment. The amount of these color pigments or dyes used is appropriately in the range of 0.1 to 40% by weight, preferably 0.5 to 20% by weight. If it is less than 0.1% by weight, the coloring power and hiding payability of the adhesive layer will be poor, and if it exceeds 40% by weight, the water resistance and moisture resistance of the adhesive layer will be poor. , Not preferable.

When dispersing the above-mentioned rust preventive pigment, coloring pigment or dye, a usual dispersing means such as a ball mill, a sand grinder, an attritor or a dyno mill can be used. At the time of dispersion, a dispersion stabilizer, an anti-settling agent, an anti-caking agent or the like may be used as an additive.

The silane coupling agent that can be used in the composition of the present invention may be an ordinary silane coupling agent, for example, 3-aminopropyltriethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-methacryloxy. Propyltrimethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, vinyltris (β-methoxyethoxy) silane, vinyltriacetylsilane, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, γ-mercaptopropyltrimethoxy Examples thereof include silane, γ-mercaptoethyltriethoxysilane, γ-chloropropyltrimethoxysilane, γ-chloropropyltriethoxysilane and vinyltrichlorosilane. These silane coupling agents may be used alone or in combination of two or more.

The amount of these silane coupling agents used is appropriately in the range of 0.1 to 10% by weight, preferably 0.4 to 6% by weight, based on the weight of the binder. 0.
When it is less than 1% by weight, the composition exhibits poor water resistance or boiling water resistance, while when it exceeds 10% by weight, the composition has poor pot life, adhesive strength and processability. Like

The composition of the present invention preferably consists of three components.

Component (a) consists of an acrylic polymer. Ingredient (b)
Contains an epoxy resin, an anticorrosive pigment, and a coloring pigment or dye. Component (c) consists of a silane coupling agent. The three components of this composition are mixed before using the composition. The organic solvent used in the composition, for example, hexane,
Aliphatic hydrocarbons such as heptane and octane, alicyclic hydrocarbons such as cyclohexane, aromatic hydrocarbons such as benzene, toluene and xylene, methanol, etal, n-propanol, isopropanol, butanols, cyclohexanol, benzyl alcohol, etc. Alcohols, acetone, methyl ethyl ketone, methyl isobutyl ketone, diethyl ketone, cyclohexane and other ketones, methyl acetate, ethyl acetate and other esters, diethyl ether, dioxane, tetrahydrofuran and other ethers, methyl cellosolve, ethyl cellosolve and other glycols There are ethers, dimethylformamide, dimethylsulfoxide, benzonitrile and the like, preferably alcohols, esters and aromatic hydrocarbons.

The content of the binder (A) and the organic solvent (B) is 10 to 80% by weight, preferably 15 to 50% by weight of the binder (A), and 90 to 20% by weight of the organic solvent, preferably 8%.
It is 5 to 50% by weight.

The adhesive composition of the present invention is applied to a hot dip galvanized steel plate or aluminum plate of a substrate by applying a commonly used coating method such as roll coating and curtain flow coating, followed by heat drying and immediately rolling. A Tedlar film is laminated by a lamination method to obtain a coated steel plate and a coated aluminum plate.

Further, the obtained coated metal plate has good adhesion to the substrate and excellent corrosion resistance.

(Function) The adhesive composition of the present invention provides a laminate of an excellent polyvinyl fluoride film and a hot dip galvanized steel plate or an aluminum plate. Further, the adhesive composition of the present invention, the adhesiveness, boiling water resistance, wet resistance, corrosion resistance or weather resistance performance can be exhibited in a well-balanced manner, and a polyvinyl fluoride film and hot dip galvanized that have better performance than conventional ones. It has the function of producing a laminate of a steel plate and an aluminum plate.

(Example) Next, a polymer synthesis example of the present invention, a pigment dispersion example in an epoxy resin, a compounding example and an example will be shown.

Synthesis Example 1 of Acrylic Polymer In a glass reactor 2 equipped with a stirrer, a cooler, a thermometer and a nitrogen gas inlet, 180 g of methyl methacrylate, 180 g of butyl methacrylate, 75 g of butyl acrylate, 60 g of methacrylic acid and as a solvent were used. 68
3 g of toluene and 293 g of isopropyl alcohol were charged together with 1.5 g of azobisisobutyronitrile as a polymerization catalyst, and polymerization was carried out at 80 to 85 ° C. for 12 hours while stirring while introducing nitrogen gas. After that 3
After adding 0 g of ethyleneimine and reacting at 80 to 85 ° C. for 3 hours, unreacted ethyleneimine was distilled off under reduced pressure to obtain an aminoalkyl ester group-containing acrylic polymer solution. The heating residue of this polymer solution is 35.0
# 4 Ford cup viscosity at 20 ° C is 220 by weight.
It was seconds. Number average molecular weight by GPC is 34,000
Met. Furthermore, the free ethyleneimine concentration was 0.
It was 3 ppm.

Example of Dispersion of Pigment in Epoxy Resin Dispersion Examples 1 to 5 Pigments, dyes and additives were dispersed in a particle size of 6 μm or less using a disperser at the compounding ratios shown in Table 1.

Adhesive composition formulation examples 1 to 7 Adhesives prepared by combining the component (a) acrylic polymer solution, the component (b) pigment-dispersed epoxy resin, and the component (c) silane coupling agent, synthesized as described above, in the combination ratios shown in Table 2. A composition was prepared.

Hereinafter, the present invention will be described in more detail with reference to examples.

Example 1 Adhesive composition of formulation example 1 of Table-2 (100 parts by weight of acrylic polymer solution of synthesis example 1, 10 parts by weight of pigment-dispersed epoxy resin of dispersion example 1, silane coupling agent (APS-
E) consisting of 1 part by weight of 3 components) and having a thickness of 38 μ
m pigment-containing polyvinyl fluoride film (Tedlar film 150 BL30HB: DuPont) and a thickness of 0.
A 4 mm hot-dip galvanized steel plate (a plate chemical-treated with Bonderite BT3920 manufactured by Nippon Parkerizing Co., Ltd.) was laminated by the following method. The thickness after drying is 6μ on one side of the steel plate.
m, then dried and heated in an oven for 40 seconds so that the steel plate temperature becomes 200 ° C., while maintaining the temperature as it is, immediately use a roll laminator to apply a linear pressure of 7 kg to the film. laminated at / cm,
Immediately cooled, a polyvinyl fluoride film-coated steel sheet was obtained.

Various tests were conducted on the obtained coated steel sheet to evaluate the adhesive composition.

The evaluation results were as shown in Table-3.

(Evaluation method) Adhesiveness: Adhesive strength is evaluated by an Erichsen test according to JIS K6744.

Evaluation criteria: 5 (hard peeling is difficult) ↑ ↓ 3 (forced peeling is possible) ↑ ↓ 1 (spontaneous peeling) Water resistance to boiling: This is a test showing the adhesiveness after the laminated product is immersed in boiling water for 2 hours. The test method and evaluation after immersion in boiling water are the same as the adhesiveness.

Corrosion resistance: Salt spray test 10 according to JIS K6744
The degree of rusting is evaluated at 00 hours.

(Suga salt water spray tester ST-ISO-3) Evaluation: Almost no rusting .... 5 Rusting is remarkable .... 1 Wetting resistance: In a test showing adhesion after 20 days at 50 ° C. and 95% RH or more. is there.

(Suga Wetness Tester CT-3) The test method and evaluation are the same as the adhesiveness.

Weather resistance: A test showing the adhesion after 1000 hours with a weather meter.

(Suga Sunshine Super Long Life Weather Meter WEL-SUN-PC-B-EM) Examples 2 to 5 and Comparative Examples 1 to 3 Adhesive composition formulation examples 2 to 7 in Table 2 were carried out in the same manner as in Example 1. Then, the evaluation test was performed.

Comparative Example 3 is an adhesive composition for Tedlar metal manufactured by DuPont.

The evaluation results were as shown in Table-3.

Example 6 Using the adhesive composition of formulation example 5 in Table-2, thickness 38 μm
m pigment-containing polyvinyl fluoride film (Tedlar film 150BL30HB: manufactured by DuPont) and thickness 1.
A 5 mm aluminum plate (a plate chemically treated with Bonderite BT-721 manufactured by Nippon Parkerizing Co., Ltd.) was laminated by the method of Example 1 and an evaluation test was conducted.

The evaluation results were as shown in Table-3.

(Effect of the invention) Since the present invention has the constitution as described above, and as is clear from the examples in particular, (a) an acrylic polymer having an amino ester pendant group,
(B) Adhesion and weather resistance in combination with an epoxy resin, and by incorporating a suitable rust preventive pigment and coloring pigment in the epoxy resin of (b), it is useful for confirming corrosion resistance and coating unevenness during operation. Produce a laminated product of polyvinyl fluoride film, hot-dip galvanized steel plate and aluminum plate, which has a better balance of boiling water resistance and wet resistance with the coupling agent of c) and has better performance than conventional ones. It has the effect of being able to.

Front page continuation (72) Kazuo Kodama, Inventor Kazuo Kodama, 14-1 Chidori-cho, Kawasaki-ku, Kawasaki-city, Kanagawa Nihon Catalysis & Chemicals Co., Ltd.Kawasaki Laboratory (72) Kenjiro Kaneko Kimitsu, Kimitsu-shi, Chiba 1 Building material industry Co., Ltd. Kimitsu Manufacturing Co., Ltd. (56) Reference JP-A-59-102919 (JP, A) JP-A-53-105556 (JP, A) "New Epoxy Resin" edited by Hiroshi Kakiuchi (SHO-60-5-10) ) Shokoido P. 540

Claims (1)

[Claims] 1. An adhesive for laminating a polyvinyl fluoride film and a hot-dip galvanized steel plate or an aluminum plate, which comprises (A) a monomer composed of methyl methacrylate, an alkyl methacrylate, an alkyl acrylate or a mixture thereof and an unsaturated carboxylic acid. An adhesive composition containing a polymer obtained by polymerizing and then reacting with an alkyleneimine, (B) a dispersion of an anticorrosion pigment in an epoxy resin, and (C) a silane coupling agent. object.