JPS6053703B2 - laminate - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a laminate having significantly improved surface properties of a molded product consisting essentially of polyethylene terephthalate.

More specifically, the surface performance, particularly the abrasion resistance and adhesion properties, of a molded product consisting essentially of polyethylene terephthalate, a vinyl polymer mainly consisting of a specific linear polyester resin, and a specific melamine group-containing (meth)acrylate. and a laminate with significantly improved durability. Polyethylene terephthalate has excellent physical properties such as mechanical and electrical properties, and has a wide range of uses as molded products such as fibers, films, sheets, and plastics, and is an extremely useful polymer compound.

However, since molded products made of polyethylene terephthalate have a flexible surface, they are resistant to abrasion (Abr).
The surface is easily damaged by dirt, dust, scratches, etc. Due to the fine scratches on the surface thus generated, the surface becomes cloudy and the molded product itself loses its transparency and surface smoothness. This phenomenon often significantly reduces or eliminates the practical value of molded products such as films, sheets, and plastics. Various methods have been proposed to date to improve the abrasion resistance of polyethylene terephthalate molded products. That is, for example, vapor deposition of inorganic glass, SiO2, etc., surface coating with condensates of organosiloxane, polysilicic acid, etc. are known.

However, polyethylene terephthalate has high crystallinity;
Coupled with poor adhesion, it is rare to find a material that combines high abrasion resistance with adhesion, flexibility, dimensional stability, workability, etc. The present inventors have previously proposed a method of coating a polyethylene terephthalate molded product with a polymer mainly consisting of a specific melamine group-containing (meth)acrylate as a method for improving the abrasion resistance of such a polyethylene terephthalate molded product. According to this method, the surface performance, especially the abrasion resistance, of polyethylene terephthalate molded products is significantly improved.
Furthermore, a laminate having excellent water resistance and moisture resistance among other durability can be obtained. However, depending on the application, the laminate obtained by this method may not necessarily have sufficient adhesion and durability, and further improvement may be required. As a result of intensive research aimed at obtaining a laminate with excellent abrasion resistance, adhesion, and durability, the present inventors have developed a polymer mainly composed of a polyethylene terephthalate molded product and melamine group-containing (meth)acrylate. The present invention was achieved by discovering that the above object can be achieved by providing a specific linear polyester resin layer between the two layers.

That is, the present invention provides a molded product (1) consisting essentially of polyethylene terephthalate, a molded product (1) provided on the molded product (1), which is soluble in dioxane or tetrahydrofuran, and which is soluble in dioxane or tetrahydrofuran at 6°C.
A linear polyester resin layer with a glass transition point of
■), and the following general formula [
However, in the formula, Rll, Rl2, Rl3 are each independently a hydrogen atom] or a methyl group; R2l, R22. R23 is each independently an alkylene group having 2 to 10 carbon atoms; R3l, R32
, R33 is a hydrogen atom, a hydrocarbon group having 1 to 10 carbon atoms, and a formula CH2=inclusive-S-0-R2O- (however, in the formula, Rl
O is a hydrogen atom or a methyl group, and R2O is an alkylene group having 2 to 10 carbon atoms.

) is a group selected from the group consisting of groups represented by ]
This is a laminate composed of a vinyl polymer layer (■) mainly composed of a melamine group-containing (meth)acrylate represented by:

The molded product (1) substantially made of polyethylene terephthalate used in the present invention has a structure in which at least 85 mol% of repeating units are represented by the following formula, and has good moldability, dyeability, flame retardancy, May contain less than 15 mol% of a copolymer component for the purpose of improving flame resistance, hygroscopicity, antistatic properties, lubricity, solvent resistance, heat resistance, mechanical properties, electrical properties, optical properties, etc. A general term for all molded products consisting of a structure, preferably films, sheets or plastics made of the polyethylene terephthalate.

The molded article (1) consisting essentially of polyethylene terephthalate and the melamine group-containing (1) used in the present invention are used in the present invention.
A vinyl polymer layer consisting mainly of meth)acrylate (
The linear polyester resin layer provided between (2) and (2) is soluble in dioxane or tetrahydrofuran and has a glass transition point of 6° C. or higher.

Such linear polyester resin contains terephthalic acid, isophthalic acid, phthalic acid, 2,6-naphthalenedicarboxylic acid, succinic acid, adipic acid, azelaic acid, sebacic acid, dodecanedicarboxylic acid, 1,4-hexanecarboxylic acid as a dicarboxylic acid component. Dicarboxylic acids such as acids, diol components such as ethylene glycol, 1,4-butanediol, 1
, 5-pentanediol, 1,6-hexanediol,
Diethylene glycol, propylene glycol, triethylene glycol, polyethylene glycol, polytetramethylene glycol, neopentyl glycol, 1,
The target is a film-forming polyester obtained by condensation copolymerization of a diol such as 4-cyclohexanedimethanol. It is necessary that the glass transition point of the linear polyester resin made of such polyester is 6° C. or higher.

When the glass transition point is less than 6°C, the melamine group-containing (
A vinyl polymer layer consisting mainly of meth)acrylate (
■) and a molded product made of polyethylene terephthalate (1
) becomes less adhesive. In particular, the glass transition point is preferably 20C or higher. Further, such linear polyester resin must be soluble in dioxane or tetrahydrofuran. By using a linear polyester resin that has a high solubility in organic solvents to the extent that it can be dissolved in dioxane or tetrahydrofuran,
A laminate with excellent adhesion and durability can be obtained. Such linear polyester resins are commercially available and can be easily obtained.

For example, various polyester resins such as Vylon resin from Toyobo Co., Ltd., Stafix resin from Fuji Photo Film Co., Ltd., and Bostik polyester resin from Bostik Japan Co., Ltd. are available. The polyester resin layer (■) usually has a thickness of 0.1 to 5 .mu.m, preferably 0.5 to 2 .mu.m, and is applied to a molded article consisting essentially of polyethylene terephthalate.

Although the film thickness is too thin, the desired high degree of adhesion cannot be achieved.
Moreover, if the film thickness is too thick, there will be an economic disadvantage. RlO9R of the melamine group-containing (meth)acrylate of the above general formula used in the vinyl polymer layer (■) in the present invention
Regarding l39R23ゞR23 and R3l''R33, RlO, Rll, Rl2 and Rl3 each independently represent a hydrogen atom or a methyl group.

R2O, R2l, R22 and R3 each independently have 2 to 10 carbon atoms. Preferably it is a linear or branched alkylene group of 2 to 6. Preferred alkylene groups include -<CH2+-2-6, ]NOH3l 1°CH2.C-CH2-, and -°CH2.CH-, 1 1-".

Also, -CH2・CH2- and -H6. This is the most suitable example considering the availability of OH monomer. R3l, R32
and R33 are each independently a hydrogen atom, a carbon atom number of 1 to
10 hydrocarbon groups and the following formula [however, in the formula, RlO, R2O
is as defined above.

A group selected from the group consisting of groups represented by ],
The hydrocarbon group is preferably an aliphatic, alicyclic, or aromatic hydrocarbon group having 1 to 8 carbon atoms.

Preferably used include methyl, ethyl, propyl, isopropyl, butyl, isobutyl, pentyl,
Examples include aliphatic hydrocarbon groups such as neopentyl, hexyl, and benzyl; alicyclic hydrocarbon groups such as cyclopentyl and cyclohexyl; and aromatic hydrocarbon groups such as phenyl and tolyl. Moreover, such a hydrocarbon group may have a substituent such as a halogen. The melamine group-containing (meth)acrylate of the present invention is obtained by, for example, a dehydrochlorination reaction between a primary and/or secondary amine having a hydroxyl group and cyanuric chloride, or an addition reaction between melamine and an epoxy compound. Easily synthesized by reacting a group-containing polyol with (meth)acrylic acid and/or (meth)acrylic acid derivatives such as (meth)acrylic anhydride, (meth)acrylic acid chloride, and (meth)acrylic acid ester. can do.

During the synthesis of the (meth)acrylate represented by the above general formula, various by-products may be obtained depending on the reaction conditions, etc., but if the amount of the by-products is small compared to the target product, the reaction mixture It can be used as is for the purposes of the present invention.

The laminate of the present invention composed of three layers as described above is manufactured by a two-step process of primer coating and overcoating.

That is, first, a coating liquid of the polyester resin is applied onto the surface of the polyethylene terephthalate molded product (1), and the solvent is removed to form the polyester resin thin film (primer coat layer) on the polyethylene terephthalate molded product (1). let Next, a coating liquid containing a melamine group-containing (meth)acrylate represented by the above general formula as a main component is applied onto the polyester resin thin film (■) (primer coat layer) of the primer coat polyethylene terephthalate molding, and the primer coat layer is A laminate is obtained by polymerizing the above. The coating liquid for the primer coat comprises at least one resin selected from the above-mentioned linear polyester resin group, and optionally additives such as surfactants and an organic solvent. Such solvents may be general organic solvents, specifically hydrocarbons such as benzene, toluene, xylene, ethylbenzene, n-hexane, heptane, petroleum ether, ligroin, cyclohexane, methylcyclohexane, methylene chloride, chloroform, Trichrene, ethylene dichloride, perchlorene, 1,1,1-trichloroethane, 1,
Halogenated hydrocarbons such as 1,2,2-tetrachloroethane, propylene dichloride, chlorobenzene, bromoethane, bromoform, methanol, ethanol, isopropanol, n-butanol, Sec-butanol,
Alcohols such as amyl alcohol, methyl amyl alcohol, cyclohexanol, ethylene glycol, trimethylene glycol, propylene glycol, glycerin, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, diethylene glycol monomethyl ether, acetone, methyl ethyl ketone, methyl isobutyl ketone , ketones such as cyclohexanone, ethers such as ethyl ether, propyl ether, butyl ethyl ether, isoamyl ether, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, tetrahydrofuran, dioxane, anisole, phenetol, acetonitrile,
Nitriles such as propylnitrile and pronitrile,
Ester systems such as methyl formate, ethyl formate, methyl acetate, ethyl acetate, propyl acetate, isobutyl acetate, amyl acetate, methyl benzoate, ethyl benzoate, N,N-dimethylformamide, N,N-dimethylacetamide, N-
Examples include aprotic polar solvent systems such as methyl pyrithone and dimethyl sulfoxide, and water.

These solvents can be used alone or in combination of two or more. The method of applying (coating) the primer coating liquid to the polyethylene terephthalate molded product includes dipping in the coating liquid, spraying, etc., application with a brush, Dr. Nice, percoater, roll, etc., roll transfer, etc. Either method is preferably used.

The polyethylene terephthalate molded product coated with the primer coating liquid is subjected to a primer coating by heating and removing the solvent using hot air, infrared rays, or the like.

The overcoat is made as follows.

That is, the coating liquid for overcoat contains at least one compound selected from the (meth)acrylates represented by the above general formula, and optionally a polymerization initiator, a polymerization inhibitor as a storage stabilizer, and various other additives. It can also be used after being diluted with an appropriate organic solvent.

Such a solvent adjusts the viscosity of the coating liquid,
It is used for the purpose of improving the "wetting" of the molded product.

Specifically, they are selected from the same group of solvents as those used for the primer coat described above, and can be used alone or in combination of two or more. The polymerization initiator used varies depending on the curing method; in the case of ultraviolet curing, benzoin ethers such as benzophenone, benzoin, benzoin methyl ether, and benzoin ethyl ether; benzyl ketals such as benzyl, benzyl dimethyl ketal, and benzyl diethyl ketal; 2- Examples include alkylanthraquinones, diacetyl, etc. In the case of heat curing, azo compounds such as azobisisobutyronitrile: benzoyl peroxide, lauryl peroxide, di-tert-butyl peroxide, dicumyl peroxide, cumene hydroperoxide, etc. Polymerization initiators can also be used in combination when ultraviolet rays and heat are used together.

The amount used is usually 001 for the (meth)acrylate.
~1% by volume. Furthermore, when using gamma rays, electron beams, or the like as a curing means, it is not necessarily necessary to add a polymerization initiator. Polymerization inhibitors as storage stabilizers are not absolutely necessary, but include, for example, hydroquinone, hydroquinone monomethyl ether, catechol, 2,6-di-Te.
Examples include rt-butylphenol, N-nitrosodiphenylamine, phenothiazine, etc., and are usually used in an amount of 10 to 1000 ppm based on the (meth)acrylate.

As various other additives, for example, stabilizers such as ultraviolet absorbers and antioxidants, pigments, optical brighteners, fillers such as glass fibers, glass powders, clays, magnetic materials, and carbon may be added.

Moreover, the coating liquid is represented by the general formula (meth)
Vinyl monomers can usually be added to an extent that does not impair the abrasion resistance and radiation resistance of the cured acrylic ester product.

Such monomers include styrene, methyl methacrylate, acrylonitrile, acrylic acid, vinyl acetate, methacrylamide, 2-hydroxylethyl acrylate, tetrahydrofurfuryl methacrylate, 2-ethylhexyl methacrylate, tetramethylene glycol diacrylate, diethylene glycol dimethacrylate, polyethylene Examples include glycol dimethacrylate, trimetherolpropane triacrylate, bisallyl carbonate, diallyl phthalate, n-butyl allyl ether, and the like. The method for applying (coating) the overcoating liquid to the primer-coated polyethylene terephthalate molded product is the same as the above-mentioned primer coating.

When the coating liquid is diluted with a solvent, the primer-coated polyethylene terephthalate molded product coated with the overcoating liquid can first be heated to remove the solvent, or if it does not contain the solvent, it can be directly polymerized. can.

Polymerization (curing) is carried out by ultraviolet rays, heat, gamma rays, electron beams, or a combination thereof, preferably by ultraviolet rays, heat, or a combination thereof. The (meth)acrylate represented by the above general formula is Most of them are air curable (
Because it is not inhibited by oxygen in the air), it is often not necessary to use an inert gas such as nitrogen, reduce pressure, or block the air with a film or glass during polymerization. The thus obtained laminate of the present invention has excellent surface performance, particularly excellent abrasion resistance, and also has excellent adhesion between each layer and excellent durability, so it can withstand extremely harsh conditions. It can withstand various usage conditions and is used for a wide range of purposes, such as being preferably used even under conditions where it is exposed to wind and rain.

EXAMPLES Hereinafter, the present invention will be explained with reference to Examples, but the present invention is not limited thereto in any way.

In addition, all parts in the examples mean parts by weight.

Reference Example [Synthesis of melamine group-containing (meth)acrylate] A solution consisting of 1,844 parts of cyanuric chloride and 413 parts of dioxane was poured into 6 (4) parts of ice water with vigorous stirring to obtain a slurry.

3161 parts of diethanolamine was added at a temperature of 30' in the reaction system.
It was added dropwise to the slurry while being externally cooled to below C. After the dropwise addition, several drops of the phenolphthalein solution were added, and the reaction system was gradually heated to reflux temperature, which was further maintained under reflux for 2 hours. During the heating and refluxing period, a solution consisting of 12 parts of sodium hydroxide and 30 parts of water was added dropwise while paying attention to coloration of phenolphthalein in the reaction system. The reaction mixture was then cooled and the solvent was removed to dryness. The reaction mixture was extracted with n-butanol and directly recrystallized to obtain acicular crystals of hexax(hydroxyethyl)melamine 24. Hexakis(hydroxyethyl)melamine 39.1 parts and p-methoxyphenol 0
．． Part ω was dissolved in 10 parts of acrylic acid, 8 parts of acrylic anhydride was added dropwise to the solution at room temperature while stirring, and the mixture was reacted at 402 to 5 CfC for 5 hours. The reaction mass was poured into 1200 ml of water under vigorous stirring and the organic layer was separated.
Add 20% of ethyl acetate to the organic layer, wash twice with an aqueous sodium carbonate solution, repeat the washing with water three times, separate the organic layer, add (one part) of magnesium sulfate to the organic layer, and after drying, remove the solvent under reduced pressure. A viscous liquid of hexakis(acryloyloxyethyl)melamine was obtained. Examples 1 to 4, Comparative Examples 1 to 4 5% by weight dioxane solutions of various linear polyester resins listed in Table 1 were respectively applied on polyethylene terephthalate stretched films of 100 μm (3 times in the longitudinal direction and 3 times in the transverse direction). It was coated using a Percoater and dried for 2 minutes in a 12C hot air oven to form a primer layer with a thickness of about 1 μm.

Next, hexas(2-acryyloxypropyl) melamine 50W), benzyl dimethyl ketal 0.5W
) and methyl isobutyl ketone was applied onto the primer layer and, after drying at 120'C, was UV cured to form a cured coating of about 3 microns. For comparison, a sample was also created in which the above acrylate solution was applied directly onto a stretched polyethylene terephthalate film without a primer coat and cured with UV light (Comparative Example 4).
.

All of the laminates obtained in Examples 1 to 5 described above have remarkable abrasion resistance. For example, even when strongly rubbed with #0000 steel wool, there is almost no damage, and as a result of the sand drop test (#80 Carborundum 500y) had a haze value of 3 to 4%.

Note that the haze value of the polyethylene terephthalene stretched film alone was 57%. To evaluate the adhesion of the laminate, initial adhesion and adhesion durability were measured.

The measurement method for such evaluation is as follows. Initial adhesion: Expressed by the number of cellophane tape peeling tests until the laminate was completely peeled off using a cross-cut test method.

Adhesion durability: The adhesion after the laminate was immersed in 80'C hot water for 8 days was measured by the method described above.

Examples 6 and 7 Comparative Examples 5 to 7 A primer coating of various polyester resins with a thickness of about 1 μm was applied to an unstretched polyethylene terephthalate film having a thickness of 250 μm in the same manner as in Example 1.

Then, hexakis (2-acrolyyloxyethyl)
A coating solution consisting of part melamine (a), 0.5 parts of benzoin ethyl ether, and 50 parts of isopropyl alcohol was applied onto the primer layer, dried at 50°C, and then cured with ultraviolet light to form a cured coating with a thickness of about 3p. .

For comparison, a sample was prepared in which the acrylate solution was applied directly onto the surface of an unstretched polyethylene terephthalate film without ply coating and photocured (Comparative Example 7).

Both of the laminates of Examples 6 and 7 described above had remarkable wear resistance.

For example, the results of the sand drop test all showed a haze value of 2 to 3%. (The unstretched polyethylene terephthalate film itself contained % tin.

) The adhesion was also evaluated in the same manner as in Example 1, and the results are shown in Table 2.

Examples 8 and 9 Using Vylon RV-200 as the polyester resin and methyl ethyl ketone as the solvent, primer coating was applied to polyethylene terephthalate stretched films in various thicknesses.

Next, the acrylate coating liquid used in Example 1 was applied and photocured to form a cured coating of about 3 μm.

Both laminates had remarkable abrasion resistance.

Claims (1)

[Scope of Claims] 1. A molded product (I) consisting essentially of polyethylene terephthalate, and a linear polyester provided on the molded product (I) that is soluble in dioxane or tetrahydrofuran and has a glass transition point of 6°C or higher. The following general formula provided on the resin layer (II) and the resin phase (II) [However, in the formula, R_
1_1, R_1_2, R_1_3 are each independently a hydrogen atom or a methyl group; R_2_1, R_2_2, R_2
_3 each independently represents an alkylene group having 2 to 10 carbon atoms;
R_3_1, R_3_2, R_3_3 are hydrogen atoms, hydrocarbon groups having 1 to 10 carbon atoms, and formulas ▲ Numerical formulas, chemical formulas, tables, etc. ▼ (However, in the formula, R_1_0 is a hydrogen atom or a methyl group, and R_2_0 is a carbon A laminate consisting of a vinyl polymer layer (III) mainly composed of a melamine group-containing (meth)acrylate represented by the following group.2 The film base of the linear polyester resin layer is 0. .1～
The laminate according to claim 1, which has a thickness of 5μ.