JPS61283541A - Manufacture of composite panel - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention #'i is a method for manufacturing a composite panel in which a composite/quad panel consisting of a front surface material and a back surface material can be obtained with good workability.

(Conventional Technique v#) For example, when a synthetic resin plate with a beautiful appearance is used as a surface material and is bonded to a back plate made of fI4 to obtain a composite beak, the adhesive used is conventionally chloroprene-based. Solvent-based adhesives, epoxy-based adhesives, and type f) adhesives have been used.

However, chloroprene-based solvent-based adhesives generally have insufficient heat resistance and have poor workability because they require coating on both the front and back surfaces, that is, double-sided coating. In particular, when applying adhesive by spraying, the adhesive often adheres to the back side of the applied surface.1. This has the disadvantage that it stains the surface of a surface material that requires a good appearance.

In addition, in the case of epoxy-based reactive adhesives, the adhesiveness is extremely low, so if the surface material is warped, for example, lifting may occur immediately after being crimped to the back surface material, so the crimping time must be extended. There was a drawback that it was not possible.

(Problems to be Solved by the Invention) In view of the above-mentioned drawbacks of the conventional / tunnel manufacturing method, the object of the present invention is to provide an adhesive that has good heat resistance and good initial adhesion even when coated on one side. It is an object of the present invention to provide a method for manufacturing a composite panel, which can be used to industrially manufacture a composite panel with good workability.

(Means for Solving the Problems) The method of the present invention uses a thermoplastic polyurethane resin-polyisocyanate solvent-based adhesive containing a tackifying resin. After volatilizing the adhesive, the adhesive coated surface Km of the back surface material is brought into contact with the surface material and pressed and solidified.

Thermoplastic polyurethane resin in the present invention refers to a polyurethane resin that is a high molecular weight linear polymer and exhibits thermoplastic properties, but it is of course a completely thermoplastic resin, but only a small portion! 1! Although the molecular weight is not specified, those having a weight average molecular weight of so, ooo to 20'0.000 are generally used.

This is because if the molecular weight is too low, the cohesive force of the adhesive itself will be low and the initial adhesive force will be low, and if the reverse pressure molecular weight is too high, the solvent solubility will be poor and the coating workability will tend to be reduced.

Such thermoplastic resins are produced by using, for example, a bifunctional active hydrogen compound such as a polyester or polyether having hydroxyl groups at both ends, and a urethane polymer having an NGO group at the end obtained from a diisocyanate or a diisocyanate and a polyol. It can be obtained by reacting the active water hydrogen groups and isocyanate groups in equivalent quantities.

In addition, polyisocyanate) Fi1 used as a curing agent
A compound having two or more VC isocyanate groups in the molecule, specific examples of which include keto, luene diisocyanate (TDI), methylene bisP 7 z nylene diisocyanate (MDI), hexamethylene diisocyanate, triphenylmethane triisocyanate, etc. .

Although the amount mixed in these adhesives is not specified, it is generally 5 to 200 parts by weight per 100 parts by weight of the thermoplastic polyurethane resin. It is believed that the polyisocyanate reacts with the thermoplastic polyurethane resin and causes allophanate crosslinking to increase the heat resistance of the adhesive.

Specific examples of the tackifying resin in the present invention include alkylphenol resins that are a reaction product of alkylphenol and aldehyde, and terpene-modified phenol resins obtained by modifying phenolic fats that are a reaction product of phenols and aldahyde with terpenes. , rosin modified phenolic resin,
Examples include rosin, rosin ester, cyclohexanone resin, coumaron resin, xylene ili% phenol-modified xylene resin, phthalic acid resin, etc., and particularly preferred are alkylphenol resin, terpene phenol resin, rosin-modified phenol resin, phenol-modified xylene resin, etc. .

These tackifying resins are usually used in an amount of 5 to 200 parts by weight per 100 parts by weight of thermoplastic polyurethane resin, and together with the thermoplastic polyurethane resin, they give the adhesive appropriate initial tackiness and initial adhesion. This enables single-sided coating (applying adhesive only to the back material) during composite/single-wall manufacturing.

Solvents used in the manufacture of adhesives include methylene chloride, methyl ethyl ketone, acetone, ethyl acetate,
In addition to good solvents for polyurethane such as butyl acetate, there may be mentioned poor solvents for polyurethane such as toluene, xylene, hexane, etc., which are used in combination with these solvents.

VcFi for producing adhesives generally involves dissolving a thermoplastic polyurethane resin and a tackifying resin in the above-mentioned solvent, adding a small amount of an appropriate modifier to the adhesive as needed, and adding a polyisocyanate immediately before use. Of course, polyisocyanate dissolved in a solvent in advance may be added.

Specific examples of surface materials used in the present invention include synthetic resin boards, synthetic rubber boards, decorative boards, plywood, wood, metal boards such as iron and aluminum (which may be painted), and laminates thereof. Non-porous plates such as synthetic resin plates and metal plates are preferably used. In addition, the back material is bonded to the surface material,
It is laminated to form a composite panel and is used in a way that makes it less noticeable (M) than surface materials.
Although the same surface materials as those described above can be used, metal plates and painted metal plates are mainly used.

Of course, a laminate may be used.

The adhesive can be applied to the backing material by a spraying method such as an air spray method or an airless spray method, or by a curtain 70 method.
- Conventionally known methods such as a coater method, a roll coater method, and a knife coke method can be used. The spraying method is generally
Since the adhesive often wraps around to the back side of the coated surface, it is preferably employed in the present invention, where there is no need to coat the adhesive on the surface material.

After that, volatilize the solvent at room temperature or by heating as appropriate.
The adhesive coated surface of the backing material is brought into contact with the hidden surface of the Kfc facing material, and the adhesive is pressed using a roll press, a plane press, or the like. The crimping may be instantaneous, and it is advantageous to use a roll press in terms of workability. The temperature and pressure at this time are appropriately selected depending on the type of surface material and back material, strength, required dimensional accuracy, etc., but the temperature is generally about room temperature to 110 ° C.
From the viewpoint of workability, it is preferable to use room temperature.

(Example) Hereinafter, parts simply refer to parts by weight.

Example 1 Dasmocur 400 (manufactured by Sumitomo Peyer Cretan, weight average molecular weight approximately 100,000) as a thermoplastic polyester polycretan resin was added to 2800 parts of methyl ethyl but.
100 parts of Tamanol 581 (as a tackifying resin)
Mix and dissolve 100 parts of alkylphenol (manufactured by Shiyo Kagaku Co., Ltd.), and add methylene bis P7 = Renji to the resulting solution.
50 parts of triancyanate (MDI) were added to obtain a solvent-based adhesive with a pot life of about 24 hours.

This adhesive was applied to the back side of a painted steel plate (thickness approximately α8%) to a thickness of approximately 200 μm using an air spray method.
It was dried for 3 minutes at ℃. A melamine resin decorative board with a thickness of approximately 1% is overlaid on the adhesive-coated surface of this backing material, and a linear pressure of 2 If is applied.
/ (To) and at room temperature, the two were pressed together using a roll press.

Initially, the melamine resin decorative board had a slight warp on the peripheral edge, but after being crimped with a roll press, it adhered well to the steel plate and the warp did not improve at all. Then Miya i! approx. 2
After being left for 4 hours, a composite panel in which the painted steel plate and the melamine resin decorative board with a beautiful surface were firmly adhered was obtained, and its tensile strength was measured. Results #i were as shown in Table 1.

Comparative Example 1 Adhesive was applied only to the painted steel plate in the same manner as in Example 1, except that a chloroprene adhesive (Nisudine 2753 M 2-, manufactured by Tsukimizu Kagaku Kogyo Co., Ltd.) was used instead of a solvent-based adhesive. The melamine resin decorative boards were stacked one on top of the other and pressed together with a roll.

The adhesion between the steel plate and the decorative plate was poor, and the warpage that had initially appeared on the periphery of the decorative plate remained uncorrected even after crimping, and eventually the decorative plate was completely separated from the steel plate, resulting in a composite/rubber plate. 'i
I couldn't get it.

Comparative Example 2 When the chloroprene solvent-based adhesive used in Comparative Example 1 was applied to both the painted steel sheet and the melamine resin decorative board used in Example 1 to a thickness of approximately 200 μm using an air spray method, the melamine resin decorative board The adhesive stuck to the surface of the board.

Thereafter, it was dried at 80° C. for 3 minutes, and the surfaces coated with the adhesive were pressed together using a roll press at a linear pressure of 2) f/m, and the tensile strength was measured after being left at room temperature for 24 hours.

As a result, the heat resistance shown in Table 1 was insufficient.

Comparative Example 3 An epoxy-polyamide based adhesive (Nisgain 3100, manufactured by Uzukumizu Kagaku Kogyo Co., Ltd.) was applied to the back side of the same steel plate as used in Example 1 to a thickness of about 200 μm, and a melamine resin coating was applied. The plates were stacked and crimped using a room temperature roll press with a linear pressure of 2 K9/ts. At this time, the periphery of the melamine resin decorative board was slightly raised due to warping. Then, after pressing for another 24 hours (IQ/ctI, 2oC), the composite panel was left for 24 hours. The tensile strength measurement result F'i is as shown in Table 1, and the heat resistance was improved compared to Comparative Example 2, but inferior to Example 1.

@ 1 Table (Effects of the Invention) According to the method of the present invention, as described above, a composite channel can be produced industrially with good workability.

That is, the method of the present invention uses a solvent-based adhesive containing a tackifying resin, a thermoplastic polyurethane resin, and a polyisocyanate to obtain a composite beak from a face material and a backing material. Compared to using conventional chloroprene-based solvent-based adhesives, which require adhesive to be applied to the backing material, the adhesive only needs to be applied to the backing material, so the area to be applied is smaller, and a good appearance is required. Since there is no risk of staining the surface of the surface material being used, a composite panel can be obtained with good workability.

In addition, since the initial adhesion is sufficient, even if the surface material is slightly warped, there is no need to press the surface material and the back material for a long time, unlike when using an epoxy-based reactive adhesive.

Furthermore, according to the present invention, a composite rope with excellent heat resistance and compaction can be obtained due to the action of the polyisocyanate.

Claims (1)

[Scope of Claims] 1. After applying a solvent-based adhesive containing a tackifying resin, a thermoplastic polyurethane resin, and a polyisocyanate to the backing material and volatilizing the solvent, A method for manufacturing a composite panel, characterized by bringing surface materials into contact and pressing and solidifying them. 2. The content of the tackifier resin is 5 to 200 parts by weight per 100 parts by weight of the thermoplastic polyurethane resin, and the content of polyisocyanate is 10 parts by weight of the thermoplastic polyurethane resin.
The manufacturing method according to item 1, wherein the amount is 5 to 200 parts by weight relative to 0 parts by weight. 3. The manufacturing method according to item 1 or 2, wherein the adhesive application method is a spraying method.