JPH05186757A - Adhesive composition for laminated metal sheet - Google Patents

Abstract

PURPOSE:To provide an adhesive compsn. which can bond a low-melting fluororesin film at a temp. lower than the m.p. of the film and is suitable for laminating the film. CONSTITUTION:An adhesive compsn. for laminating a fluororesin film is prepd. by compounding an epoxy resin, a cross-linker therefor, an acrylic resin, and a fluororesin as the essential components. A coupling agent and/or a catalyst for the reaction between the epoxy resin and the cross-linker may be added to the compsn., and a pigment may also be added. Since the adhesive can bond the film at a low temp., the film can be laminated to a metal sheet without causing bad appearance, breaking, wrinkles, and stretching of the film.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an adhesive composition for producing a metal plate laminated with a fluororesin film exhibiting excellent weather resistance. The fluorine-based laminated metal sheet produced by using this adhesive is suitable for outdoor building materials by utilizing its weather resistance.

[0002]

2. Description of the Related Art In recent years, a fluorine-based laminated metal plate laminated with a fluorine-based resin film (hereinafter abbreviated as "fluorine-based film") has a maintenance-free property.
Demand is increasing for outdoor building materials and highway noise barriers. Note that the fluorine-based film means a film of a fluororesin and a fluororesin and another resin (eg, acrylic resin, etc.)
It is meant to include both films of mixed resins with.

Regarding such a fluorine-based laminated metal plate, the technology is disclosed in Japanese Patent Publication Nos. 60-51423 and 6051424, and Japanese Patent Laid-Open No. 63-168333 discloses a fluorine-based film. Techniques for laminating methods are described.

Japanese Unexamined Patent Publication No. 63-168333 relates to a method for laminating a fluorine-based film. In the middle part of the third page of the publication, "As an adhesive ... There is no suitable adhesive that is effective at low temperatures, as described in "There is no adhesive" that is currently used at a temperature of around 200 ° C. The reality is that it is unavoidable.
In this way, in the combination of the film and the adhesive whose bonding temperature is significantly higher than the melting point of the film, as pointed out in the above publication, wrinkles, breakage, and elongation of the film at the time of lamination may cause manufacturing problems. I will be holding it.

The melting point of the film can of course be raised or lowered by changing the composition of the film, but in that case the physical properties of the film such as weather resistance also change, so it is actually necessary to raise the melting point of the film. It is often difficult. Therefore, development of a low temperature type adhesive capable of low temperature adhesion has been desired.

Although not specifically described in JP-A-63-168333, a fluorine-based film-laminated metal plate for building materials has a low-gloss calming property in which fine unevenness is applied to the film surface. Those with a sense of luxury are preferred. However, when the laminating temperature becomes high as described above, the film resin is leveled, fine irregularities on the film surface disappear, and the gloss is increased, so that the commercial value is significantly impaired. Such a phenomenon can be avoided by using a low temperature type adhesive.

On the other hand, paint-type resin-coated steel sheets for building materials, which are obtained by baking-coating a resin coating containing vinylidene fluoride as a main component and having excellent weather resistance, are commercially available. In order to use this resin-coated steel sheet for production, Primers with good adhesion to topcoat paints (mixture of vinylidene fluoride resin and acrylic resin) are already on the market. This primer has good adhesiveness to vinylidene fluoride, but it cannot be used as it is as an adhesive for laminating a fluorine-based film. This is because, in the baking coating of the above paint, the liquid topcoat paint is applied on the primer coat and baking at high temperature for a long time (the baking temperature and time of the topcoat is 200 to 250 ° C for about 1 minute). This is because in terms of drying, the situation of use is significantly different from that of the laminating adhesive of the present invention.
U.S. Pat. No. 4,314,004 discloses a primer composition used for the same purpose, but for the same reason, it cannot be directly used as an adhesive for low temperature type laminating.

Further, most adhesives are of two-pack type,
The liquid type is advantageous because the workability is improved.

[0009]

SUMMARY OF THE INVENTION An object of the present invention is to provide a thin fluorine film having a low melting point with a metal film without causing problems such as wrinkles, breakage and elongation, and eliminating the unevenness of the film surface. Can be laminated on board,
It is to provide a low temperature type one-pack type adhesive composition.

In a normal laminating line, after an adhesive is applied on a metal plate, the adhesive is baked and dried,
Immediately after that, the film and the metal plate are laminated by the laminator. Therefore, the temperature at the time of bonding with the film (hereinafter,
The lamination temperature) is only slightly lower than the baking and drying temperature of the adhesive (hereinafter called the baking temperature),
To lower the laminating temperature, it is necessary to lower the baking temperature. Therefore, the low temperature type adhesive must be capable of low temperature baking and low temperature lamination. The low temperature type adhesive provided by the present invention means such an adhesive.

A specific object of the present invention is to bond the adhesive at a baking temperature of about 180 ° C., and at a laminating temperature of about 160 ° C. or less, which is close to the melting point of the fluorine-based film, to complete lamination by pressure bonding for about 0.1 seconds. The present invention is to provide an adhesive for fluorine-based film laminating as described above.

[0012]

To achieve the above object, according to the present invention, an epoxy resin and its cross-linking agent, an acrylic resin, and a fluororesin are contained. An adhesive composition is provided. By adding one or both of a catalyst for a cross-linking reaction between an epoxy resin and its cross-linking agent, or a coupling agent to this composition, it is possible to further lower the baking temperature and the laminating temperature. You can definitely achieve your goals.

[0013]

The structure of the present invention will be described in detail below together with its operation. The adhesive of the present invention is used for laminating a fluorine-based film on a base metal plate. That is, the present invention relates to the adhesive composition, and does not impose any limitation on the base metal plate type and the fluorine film type.

As described above, the type of the base metal plate is not particularly limited, but the laminated metal plate produced is often used outdoors because of its excellent weather resistance, and the base metal also has excellent corrosion resistance. Often applied. Examples of suitable base metal plates include stainless steel plates, zinc-based or aluminum-based plated steel plates (e.g., hot-dip zinc or zinc alloy-plated steel plates, electrolytic zinc or zinc alloy-plated steel plates, hot-dip aluminized steel plates, etc.), Are non-ferrous metal plates such as aluminum plate and titanium plate.
The metal plate may be subjected to an appropriate undercoating treatment in order to improve its corrosion resistance or the adhesiveness with the film.
Examples of the base treatment include chromate treatment and zinc phosphate treatment.

As mentioned above, the fluorine-based film is a film of a fluororesin or a mixture of a fluororesin and another resin, and the film contains a pigment, a filler, a reinforcing agent, an ultraviolet absorption inhibitor, an antioxidant. , And various other additives may be contained in one kind or two or more kinds.

The low-temperature laminating adhesive has a good adhesion to both the metal plate side (metal surface or surface treatment or surface treatment film applied to the surface) and the film to be laminated. In addition, it is required to develop within a short time.

In order to meet this requirement, the adhesive of the present invention contains at least an epoxy resin, a cross-linking agent, an acrylic resin and a fluororesin. Preferably, the epoxy resin and the cross-linking agent are combined in order to further reduce the temperature. One or both of a crosslinking reaction catalyst and a silane coupling agent are blended.

The epoxy resin is effective in securing the adhesiveness to the metal surface or the surface treatment thereof, and the primary adhesiveness is obtained by curing the epoxy resin together with the crosslinking agent.
Improvements in both (adhesion immediately after adhesion) and secondary adhesion (adhesion after aging) are expected.

On the other hand, it is often difficult to secure the adhesiveness with the fluorine-based film at a low temperature in a short time, but the adhesiveness with the fluorine-based film is improved by adding the fluorine resin to the adhesive. can do.

Since the acrylic resin is compatible with the fluororesin, it is added to secure the adhesion between the epoxy resin and the fluororesin. This is because the adhesive film made of only the epoxy resin and the fluororesin cured by the cross-linking agent is inferior in adhesiveness as it is because the layers are separated after baking.

The catalyst for the cross-linking reaction between the epoxy resin and its cross-linking agent and the silane coupling agent are effective for lowering the baking temperature of the adhesive and for improving the adhesion to the base material undercoating which is an inorganic substance. It is added as needed.

In order to secure these performances, the above resin components are 5 to 90% by weight of the epoxy resin, 0.25 to 30% of the cross-linking agent, 5 to 90% of the acrylic resin, and 5 to 90% of the acrylic resin.
The fluororesin is preferably present in the composition in an amount of 5 to 90%. It is more desirable that the amount of fluororesin be 50% by weight or more, but the addition of an excessive amount of fluororesin leads to an increase in cost.

If the amount of the epoxy resin or the cross-linking agent is too small, the adhesiveness to the surface of the base material such as undercoating, especially the secondary adhesiveness will be deteriorated. Adhesion decreases. If the amount of acrylic resin is too small, the adhesiveness between the fluororesin and the epoxy resin cannot be exhibited, as described above.

The amount of the cross-linking reaction catalyst and the silane coupling agent to be blended may be any amount as long as the above-mentioned purpose of addition can be achieved, and it is difficult to limit because it varies depending on the resin composition.
Crosslinking reaction catalyst is 0.05-5%, silane coupling agent is 0.
It is usually preferred to use an amount in the range of 01 to 5% (both by weight based on total solids).

Examples of the epoxy resin suitable for use in the present invention include epoxy compounds obtained by the reaction of bisphenols such as bisphenol A, bisphenol F and bisphenol AD with epihalohydrin or β-methylepohalohydrin, or These copolymers are mentioned. Further, monocarboxylic acid or dicarboxylic acid modified products, mono-, di- or polyalcohol modified products, mono- or diamine-modified products, mono-, di- or polyphenol-modified products of these epoxy compounds can also be used as the epoxy resin.

The crosslinking agent used in the present invention is an epoxy resin crosslinking agent, and various known crosslinking agents for epoxy resins can be used. Preferred cross-linking agents are polyisocyanate resins and amino resins, which may be used alone or as a mixture of two or more. The crosslinking agent is preferably used in an amount of 5 to 40 parts by weight with respect to 100 parts by weight of the epoxy resin.

Polyisocyanate resins useful as crosslinkers include aromatic diisocyanates such as xylylene diisocyanate, tolylene diisocyanate, 4,4'-diphenylmethane diisocyanate, aliphatic diisocyanates such as hexamethylene diisocyanate, trimethylhexamethylene diisocyanate. Alicyclic diisocyanates such as diisocyanates and isophorone diisocyanate,
Furthermore, polyisocyanate compounds such as adducts with multimers or polyhydric alcohols of these diisocyanates,
And these polyisocyanate compounds as a blocking agent (eg, phenol type, lactam type, alcohol type, active methylene type, mercaptan type, imine type, amine type,
There is a blocked polyisocyanate resin in which an isocyanate group is blocked by reacting with an imidazole-based, oxime-based, or sulfite-based blocking agent). When such a blocked polyisocyanate resin is used, an organotin compound such as dibutyltin dilaurate can be blended together as a dissociation catalyst.

Examples of amino resins useful as crosslinkers include:
For example, there is a condensate of formaldehyde or paraformaldehyde alkylated with an alcohol having 1 to 4 carbon atoms with urea, N, N'-ethyleneurea, dicyandiamide, aminotriazine or the like. Specifically, methoxylated methylolurea, Methoxylated methylol-
Examples thereof include N, N′-ethylene urea, methoxylated methylol dicyandiamide, methoxylated methylol melamine, methoxylated methylol benzoguanamine, butoxylated methylol melamine, butoxylated methylol benzoguanamine.

Cross-linking reaction catalyst of epoxy resin and cross-linking agent
Examples of (ie, curing catalyst) are acid catalysts, titanium chelating agents, titanate coupling agents. As the acid catalyst, phosphoric acid, phosphoric acid butyl ester, paratoluenesulfonic acid, dinonylnaphthalenesulfonic acid, cyclohexylsulfamic acid and the like can be used. As the titanium chelating agent, titanium acetylacetonate, tetranormal butyl titanate or the like can be used. Examples of titanate coupling agents include isopropyltriisostearoyl titanate, isopropyltridodecylbenzenesulfonyl titanate, isopropyl tris (dioctyl pyrophosphate) titanate, tetraisopropylbis (dioctylphosphite) titanate, tetraoctylbis (ditridecyl phosphite) titanate. , Tetra
(2,2-diallyloxymethyl-1-butyl) bis (di-
Tridecyl) phosphite titanate, bis (dioctyl pyrophosphate) oxyacetate titanate,
Bis (dioctyl pyrophosphate) ethylene titanate, isopropyl trioctanoyl titanate, isopropyl dimethacryl isostearoyl titanate, isopropyl isostearoyl diacrylic titanate, isopropyl tri (dioctyl phosphate) titanate, isopropyl tricumylphenyl titanate, isopropyl tri (N-aminoethyl) -Aminoethyl) titanate, dicumylphenyloxyacetate titanate,
Diisostearoyl ethylene titanate etc. are mentioned.

As the silane coupling agent, vinyltrichlorosilane, vinyltriethoxysilane, γ-chloropropyltrimethoxysilane, γ-chloropropylmethyldichlorosilane, γ-chloropropylmethyldimethoxysilane, γ-chloropropylmethyldiethoxy. Silane, γ-aminopropyltriethoxysilane, N- (β
-Aminoethyl) -γ-aminopropyltrimethoxysilane, N- (β-aminoethyl) -γ-aminopropylmethyldimethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ- Glycidoxypropylmethyldimethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-methacryloxypropylmethyldimethoxysilane, vinyltris (β-methoxy-ethoxy) silane,
β- (3,4-epoxycyclohexyl) -ethyltrimethoxysilane and the like can be mentioned.

The fluororesin may be obtained by homopolymerization of fluorine-containing monomers such as tetrafluoroethylene, chlorotrifluoroethylene, hexafluoropropylene, trifluoroethylene, vinyl fluoride and vinylidene fluoride, or copolymerization with other monomers. Any fluorine-containing polymer obtained can be used, and any thermoplastic or thermosetting resin may be used. Specifically, for example,
Examples thereof include polyvinyl fluoride and polyvinylidene fluoride. Examples of commercially available products include Kainer 500 (polyvinylidene fluoride manufactured by Atchem North America) as a thermoplastic fluororesin and Lumiflon 200 (made by Asahi Glass) as a thermosetting fluororesin.

When using a thermosetting fluororesin,
As a cross-linking agent, one or more of melamine resin, polyisocyanate and urea resin is added to the fluororesin in an amount of 5
Included in an amount of ~ 30% by weight.

As the acrylic resin, one having a high compatibility with the fluororesin to be used is preferable, and it may be either thermoplastic or thermosetting. Examples of the thermoplastic acrylic resin include polymers and copolymers of acrylic acid esters or methacrylic acid esters such as methyl methacrylate and ethyl acrylate. In this case, the ester group of the ester is methyl, ethyl, propyl, butyl,
It may be an alkyl group such as isobutyl, n-hexyl, lauryl and stearyl. In the case of a copolymer, the ester group may be one type or two or more types. The thermosetting acrylic resin, a monomer having a functional group (carboxyl group, hydroxyl group, amino group, methylol group, epoxy group, etc.) that forms a crosslinked structure in the molecule, such as acrylic acid, methacrylic acid, acrylamide, Methacrylamide, N-methylol acrylamide, allyl glycidyl ether, glycidyl methacrylate, etc., and two groups not having such a functional group, such as styrene and the above-mentioned acrylic acid or methacrylic acid ester groups, are selected. Examples thereof include polymers obtained by copolymerizing two or more kinds of monomers, but are not limited thereto.

When the above-mentioned adhesive components are mixed, the adhesive composition of the present invention can be obtained. However, since it is a solid or a highly viscous liquid and is difficult to apply as it is, it is the same as a usual adhesive. To obtain a liquid with a viscosity suitable for coating. The adhesive of the present invention can be made into a one-pack type adhesive composition in which all components are mixed by selecting a component that does not cause a crosslinking reaction at room temperature, such as blocked polyisocyanate, as a crosslinking agent. The preparation work of the adhesive before the work can be omitted, and the handling is easy. However,
If necessary, a two-component adhesive in which the crosslinking agent is separated from other resin may be used.

As the thinner, any organic solvent capable of dissolving the epoxy resin, the acrylic resin and the crosslinking agent can be used, but a general-purpose general thinner is sufficient. Specifically, it is a hydrocarbon solvent such as toluene and xylene, a ketone solvent such as methyl ethyl ketone, cyclohexanone, and isophorone. Fluororesin is insoluble in such thinner depending on the type. In that case, the fluororesin may be finely dispersed in the resin liquid.

If desired, various pigments may be added to the adhesive of the present invention in addition to the above components. Examples of pigments that can be added include general pigments such as titanium dioxide, silica, iron oxide, talc, clay, calcium carbonate and barium sulfate. Further, in order to improve the end surface corrosion resistance of the laminated metal plate, a rust preventive pigment such as strontium chromate or zinc chromate may be added to the adhesive. When these pigments are added, the amount of addition is preferably 250 parts by weight or less with respect to 100 parts by weight of the total resin content in the adhesive, and the addition of more than that significantly reduces the processability of the adhesive film.

In the case of producing a laminated metal plate using the adhesive of the present invention, the adhesive is applied to the base metal plate by a suitable coating device such as a roll coater. The coating amount is preferably about ² to 30 g / m ^{2 in} terms of the adhesion amount after baking and drying. When the pigment is added to the adhesive, the coating amount is larger than when it is not added. The metal plate coated with the adhesive is then heated to bake and dry the adhesive. The adhesive of the present invention is a low temperature type,
The baking temperature may be 160 to 200 ° C, usually about 180 ° C, which is lower than the conventional temperature.

Immediately after baking and drying the applied adhesive, the fluorine-based film is immediately supplied onto the metal plate and laminated. This laminate has a plate temperature (lamination temperature) of 14
It is completed at a pressure bonding time (time sandwiched between nip of laminating rolls) of about 0.1 seconds at 0 to 180 ° C, usually about 160 ° C. This laminating temperature can be lower than the melting point (usually about 170-190 ° C) of the laminating fluorine-based film, so there is no risk of wrinkles, breakage or elongation of the film during laminating work, easy laminating and quality Stabilize. Further, since leveling of the film during lamination can be avoided, even if the film is of a low gloss type having fine irregularities on the surface, this surface structure is maintained during lamination, and there is no fear of reducing the commercial value.

[0039]

【Example】

(Example 1) Hot-dip galvanized steel sheet subjected to a zinc phosphate-based undercoating (deposition amount 1 g / m ² ) as a base metal plate (deposition amount of plating)
120 g / m ² and a plate thickness of 0.6 mm) as a fluorine-based laminate film made of Sumitomo Bakelite vinylidene fluoride /
A laminated steel plate was manufactured using an acrylic mixed resin film (thickness 0.040 mm).

The adhesive used had the composition shown in Table 1-1.
(Parts by weight) Each resin was sampled, dissolved and dispersed in a thinner (mixed solvent of xylene / isophorone (1/1)) together with a crosslinking reaction catalyst and silane coupling agent with a paint conditioner to prepare. . The solid content concentration of the obtained adhesive was within the range of 20 to 60% by weight.

The materials used are Dainippon Ink and Chemicals, Inc.
Epoxy resin (trade name Epicron) manufactured by Dainippon Ink and Chemicals, Inc. as an amino resin used as a cross-linking agent
(Brand name Super Beckamine), Mitsubishi Rayon Co., Ltd. acrylic resin (Brand name Hi-PET), fluorocarbon resin Atchem North America vinylidene fluoride resin (Brand name Kainer), crosslinking catalyst Wako Pure medicine
The product was p-toluenesulfonic acid manufactured by K.K. and vinyltrichlorosilane as a silane coupling agent.

After drying the obtained adhesive with a bar coater, one side of the hot-dip galvanized steel sheet was coated so that the amount of adhesion was 10 g / m ^2, and it was heated in a conveyor hot air oven at 250 to 350 ° C. for about 1 minute. After baking to dry the adhesive film, the film and the steel plate were laminated with a laminator arranged on the outlet side of the oven. The laminating speed was 20 m / min and the crimp time between the laminator nip at this speed was about 0.1 seconds. The temperature immediately before entering the laminator was measured and used as the laminating temperature. Immediately after lamination, the produced laminated steel plate was water-cooled. Although the temperature of the oven was high as described above, the actual plate temperature was considerably lower than the oven temperature because of baking for a short time.

The primary adhesion of the laminated steel sheet thus produced was measured by inserting a cross slit having a width of 5 mm into the sample.
It was evaluated by conducting 5 mm Erichsen overhang and examining the adhesion of the film or adhesive. The secondary adhesion was examined by immersing the sample in boiling water for 2 hours and then performing the same Erichsen bulge. 5 points (excellent) with no film peeling in both primary and secondary adhesion
, 4 points when the cut edge is slightly peeled (good)
The one with a large degree of peeling was defined as 1 point (defective), and was evaluated on a scale of 5 according to the degree of peeling of the film. 3 in practice
It is considered that the adhesiveness is good if it is at least 4 points, preferably at least 4 points.

Regarding the surface appearance of the laminated steel sheet, visual observation of the sample shows that the case where the film maintains a uniform low gloss over the entire surface is good (○), and the case where a part with a high gloss occurs partially. The appearance was judged to be poor (×). The experimental results are shown in Table 1-2.

(Example 2) Hot dip galvanized steel sheet with a base material of coating type chromate treatment (Cr deposit amount 50 mg / m ² ) as base metal plate (plating deposit amount 120 g / m ² , plate thickness) 0.5
mm) and the same fluorine-based film as in Example 1 was used as the laminate film to produce a laminated steel plate. The adhesive used was prepared in the same manner as in Example 1 so as to have the composition (parts by weight) shown in Table 2-1. This adhesive contained a pigment, and no crosslinking reaction catalyst was added.

As an epoxy resin Dainippon Ink and Chemicals
Epicron (trade name) manufactured by K.K., and blocked polyisocyanate manufactured by the company as a cross-linking agent (brand name Barnock)
Was used, and an amount of dibutyltin dilaurate corresponding to 2% by weight of the amount of the blocked polyisocyanate added was added as a dissociation catalyst for the blocking agent. The same kiner (trade name) as in Example 1 was used as the fluororesin, γ-aminopropyltriethoxysilane was used as the coupling agent, and a titanium dioxide pigment (trade name Taipaque) manufactured by Ishihara Sangyo was used as the pigment.

After the adhesive was dried with a bar coater, the adhesion amount was 25 g.
/ m ^{2 on} one side of the above hot dip galvanized steel sheet, baked in a conveyor type hot air oven at 250 to 300 ℃ for about 1 minute to dry the adhesive, and filmed with a laminator installed on the outlet side of the oven. And the steel plates were pasted together. The laminating speed was 10 m / min and the pressure bonding time was about 0.2 seconds. The temperature immediately before entering the laminator was defined as the laminating temperature. The laminated steel sheet obtained immediately after lamination was water-cooled.

The results of evaluating the primary adhesion, secondary adhesion and surface appearance of this laminated steel sheet in the same manner as in Example 1 are shown in Table 2-2.

(Example 3) As a base metal plate, a stainless steel plate (SUS304, DF material, plate thickness 0.5 mm) subjected to coating type chromate treatment (Cr deposition amount: 50 mg / m ² ) was used and laminated. A polyvinylidene fluoride film (thickness 0.040 mm) manufactured by Denki Kagaku Co., Ltd. was used as the film.

The adhesive having the composition shown in Table 3-1 was prepared and used in the same manner as in Example 1. Although not shown in Table 3-1, the adhesive contained a pigment. As the pigment, the same titanium dioxide pigment as that used in Example 2 was added at a ratio of 180 parts with respect to 100 parts by weight of the resin and dispersed in the adhesive.

Dainippon Ink and Chemicals as epoxy resin
Epiclon (trade name) manufactured by K.K., melamine resin (trade name Super Beckamine) manufactured by Dainippon Ink and Chemicals Co., Ltd. as amino resin for cross-linking agent, and Hipet (trade name) manufactured by Mitsubishi Rayon as acrylic resin. The other crosslinking reaction catalysts used, p-toluenesulfonic acid, fluororesin, and silane coupling agent were all the same as those used in Example 1.

The lamination conditions and evaluation method are described in Example 1.
The same procedure as described in (2) and (2) (Adhesive adhesion amount: 5 g / m ² , laminating speed: 20 m / min). The test results are shown in Table 3-2.

(Example 4) Aluminum alloy plate (Al-Mg system, A5052P, mill finish) as a base metal plate, plate thickness 0.8 m
used m. Chromate phosphate (Nippon Paint, Alodine 405, 30 mg / m ² ) was applied as the base treatment. The laminated fluorine-based film was the same as that used in Example 1. Adhesives shown in Table 4-1 are used in Example 3
Prepared as in. That is, as in Example 3, the titanium dioxide pigment was added at a ratio of 180 parts to 100 parts by weight of the resin and dispersed in the adhesive.

A thermosetting fluororesin (trade name: Lumiflon) manufactured by Asahi Kasei Co., Ltd. was used as the fluororesin, and other epoxy resin, amino resin as a cross-linking agent, acrylic resin, cross-linking reaction catalyst (p-toluenesulfonic acid), The silane coupling agent was the same as in Example 3.

Lamination conditions and evaluation method are described in Example 1.
The same procedure as described in (2) and (2) (Adhesive adhesion amount: 25 g / m ² , laminating speed: 10 m / min). The test results are shown in Table 4-2.

[0056]

[Table 1]

[0057]

[Table 2]

[0058]

[Table 3]

[0059]

[Table 4]

[0060]

As can be seen from the examples, when the adhesive of the present invention is used, the laminating temperature can be lowered, the film does not have uneven gloss, and the fluorine-based film laminate has a good surface appearance. A metal plate can be manufactured. Further, by setting the adhesive composition within the range of the present invention, good primary adhesion and secondary adhesion can be obtained even at a low laminating temperature. In this way, it becomes possible to produce a laminated metal plate at a low temperature, which not only prevents the deterioration of the surface appearance but also prevents the fluorine-based film from being softened or melted during lamination, so that wrinkles in the film can be prevented. No breakage or elongation occurs, and the possibility of defective lamination is significantly reduced. Further, since the low-temperature laminating adhesive of the present invention completes the adhesion by pressure bonding in a short time, it is possible to produce a high-quality laminated metal plate excellent in weather resistance, which is obtained by laminating a fluorine-based film, with high production efficiency. Is possible.

Continuation of the front page (51) Int.Cl. ⁵ Identification number Internal reference number FI Technical indication location C09J 175/04 JFB 8620-4J (72) Inventor Koji Nakata 4-53-3 Kitahama, Chuo-ku, Osaka Sumitomo Kin Inside the industrial corporation (72) Inventor Akihiro Yauchi 4-533 Kitahama, Chuo-ku, Osaka Sumitomo Kin Metals Inside Ltd. (72) Toshiaki Shiota 4-53-3 Kitahama, Chuo-ku, Osaka Sumitomo (72) Inventor Hiroaki Tabe 3-735 Nishikori, Otsu City (72) Inventor Shingo Akagi 3-15 Takeyacho, Suita City 202 (72) Inventor Shoichi Hamajima Hamakoushien, Nishinomiya City 1-4-10 (72) Inventor Nagaharu Tanaka 2 Dejima Nishimachi Sakai City, Igeta Steel Co., Ltd. (72) Inventor Akira Tanaka 2 Dejima Nishimachi Sakai City, Inetah Steel Co., Ltd. (72) Inventor Tomohiro Minami Sakai Ichita Steel Sheet Co., Ltd. 2 Ichijima Nishimachi, Ichiga Prefecture (72) Inventor Kazuhiro Kuroki 2 Dejima Nishimachi 2 Sakai City Within the company

Claims (2)

[Claims] 1. An adhesive composition for laminating a fluororesin film, comprising an epoxy resin and a crosslinking agent thereof, an acrylic resin, and a fluororesin. 2. The adhesive composition according to claim 1, further comprising one or both of a catalyst for a cross-linking reaction between an epoxy resin and a cross-linking agent thereof, or a silane coupling agent.