JPH06287334A - Plasticized vinyl chloride resin molding covered with protective film - Google Patents

Abstract

PURPOSE:To provide a plasticized vinyl chloride resin molding covered with a protective film to impart stain and weather resistances to the molding. CONSTITUTION:A plasticized vinyl chloride resin molding is covered with a protective film formed from a compsn. which comprises a fluorocopolymer (A) consisting of 90-75mol% vinylidene fluoride units and 10-25mol% chlorotrifluoroethylene units a (meth)acrylic ester resin (B) having a glass transition point of 60 deg.C or higher, and a benzophenone or benzotriazole compd. (C) in an amt. of component C of 1-20 pts.wt. based on 100 pts.wt. the sum of components A and B.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a soft vinyl chloride resin molded article provided with an antifouling and weather resistant protective coating. The molded article of the present invention can be used as an agricultural film or a wall. Examples include materials, sheets and cloths.

[0002]

Prior art and its problems Soft vinyl chloride resin
It is used in large quantities in a wide range of applications such as agricultural films, wall materials, sheets, cloth and truck hoods. recent years,
For the purpose of saving resources and protecting the global environment, it is required to improve the durability of such a soft vinyl chloride resin molded body. As a means for the above purpose, a sheet in which a fluororesin having excellent weather resistance is laminated on the surface of a vinyl chloride resin has been proposed (for example, JP-A-60-52328), but in such a method, the fluororesin layer is used. The vinyl chloride resin layer had poor adhesion and did not have sufficient durability.

Further, it has been proposed to provide a film made of a mixture of polyvinylidene fluoride and an acrylic resin on the surface of a vinyl chloride resin sheet (Japanese Patent Publication No. 63-23).
No. 6, JP-A-62-28741, etc.), in these means, it is necessary to use an organic solvent having a high boiling point in order to dissolve polyvinylidene fluoride, and the drying step in forming a film is complicated. However, the weather resistance and antifouling properties were still a step away.

[0004]

Means for Solving the Problems As a result of intensive studies to solve the above problems, the present inventor has found that a resin composition comprising a fluorocopolymer having a specific constitution and a (meth) acrylic acid ester-based resin, Further, it was found that a coating composition having a benzophenone compound or a benzotriazole compound added as an ultraviolet absorber can adhere a coating excellent in weather resistance and antifouling property to a soft vinyl chloride resin molded product, and completed the present invention. did.

That is, the present invention provides (a) a fluorinated copolymer composed of 90 to 75 mol% of vinylidene fluoride monomer units and 10 to 25 mol% of chlorotrifluoroethylene monomer units, (b) ) A (meth) acrylic acid ester-based resin having a glass transition temperature of 60 ° C. or higher and (c) a benzophenone-based compound or a benzotriazole-based compound, and the total amount of the components (a) and (b) is 100.
A soft vinyl chloride resin molded product having a protective coating formed from a composition containing 1 to 20 parts by weight of component (c) per part by weight.

The base resins of the soft vinyl chloride resin targeted by the present invention are polyvinyl chloride homopolymers and copolymers of vinyl chloride and other monomers. Copolymerized monomers with vinyl chloride include vinylidene chloride, vinyl acetate,
Examples thereof include ethylene, acrylonitrile, maleic acid, methacrylic acid and octyl vinyl ether.

Typical plasticizers to be added to the soft vinyl chloride resin include phthalic acid esters such as dioctyl phthalate, diethylhexyl phthalate and didodecyl phthalate, and adipic acid esters such as dibutyl adipate and dioctyl adipate. To be The suitable amount of the plasticizer is 1 to 100 parts by weight per 100 parts by weight of the resin. Also, heat stabilizers, antioxidants, lubricants,
Surfactants, ultraviolet absorbers, light stabilizers, pigments and the like may be blended, and these are mixed with a vinyl chloride resin by a mixer such as a ribbon blender or a Banbury mixer. As the molding method of the soft vinyl chloride resin, methods such as calender molding, extrusion molding, injection molding and inflation molding can be adopted, and examples of the molded body include a film, a sheet and a flat plate.

As described above, the fluorine-containing copolymer used in the present invention contains 90 to 75 mol% of vinylidene fluoride monomer units (hereinafter referred to as VdF units) and chlorotrifluoroethylene monomer units (hereinafter referred to as CTFE units). 10 to 25 mol%, preferably having a ratio of VdF units / CTFE units of 8
It is a copolymer of 7/13 to 77/23 (molar ratio). V
When the amount of dF units exceeds 90 mol%, the copolymer is difficult to dissolve in an organic solvent, and when it is less than 75 mol%, the melting point of the copolymer is low and the heat resistance deteriorates.

The fluorine-containing copolymer of the present invention is superior in adhesion to vinyl chloride resin as compared with other fluororesins. In this regard, it is presumed that chlorine in the CTFE molecule has an affinity with the vinyl chloride resin. The fluorinated copolymer in the present invention is basically a binary copolymer of VdF and CTFE, but the upper limit is 20 mol% based on the total amount of all monomer units,
A fluorine-containing monomer such as tetrafluoroethylene or vinyl fluoride or another radically polymerizable monomer may be copolymerized.

The number average molecular weight of the fluorinated copolymer is preferably 1,000 to 1,000,000, more preferably 10,000 to 100,000. If the number average molecular weight exceeds 1,000,000, the viscosity of the solution becomes high and it is difficult to coat, while if it is less than 1,000, the mechanical strength of the protective layer is poor. The copolymer can be produced by a usual organic peroxide or an inorganic peroxide by suspension polymerization, emulsion polymerization, solution polymerization or the like.

Used with the above-mentioned fluorine-containing copolymer,
A (meth) acrylic acid ester-based resin (hereinafter simply referred to as an acrylic resin) having a glass transition temperature (hereinafter referred to as Tg) of 60 ° C. or higher is a methacrylic acid ester having a homopolymer Tg of 60 ° C. or higher, such as methyl methacrylate or isomethacrylate. Homopolymerization or copolymerization of bornyl methacrylate, adamantyl methacrylate, tricyclodecyl methacrylate, ethyl methacrylate, t-butyl methacrylate, or the like, or with the above methacrylic acid ester, ethyl methacrylate, butyl methacrylate, ethylhexyl methacrylate, methyl acrylate, ethyl acrylate And a (meth) acrylic acid ester such as cyclohexyl methacrylate. When the Tg of the acrylic resin is less than 60 ° C, the heat resistance is poor and the antifouling property and durability in summer are poor. An acrylic resin having a Tg of 80 ° C. or higher is preferable.

The preferred number average molecular weight of the acrylic resin is 3,000 to 200,000, more preferably
It is 5,000 to 100,000. Number average molecular weight is 20
If it exceeds 000, the viscosity of the solution tends to be high and the coating operation tends to be complicated, while if it is less than 3,000, the mechanical strength of the resulting protective layer tends to be poor.

The preferred mixing ratio of the fluorocopolymer and the acrylic resin is 10 to 50 parts by weight of the fluorocopolymer / 50 to 90 parts by weight of the acrylic resin, and more preferably 20 to 40 parts by weight of the former. / The latter is 60 to 80 parts by weight. If the ratio of the fluorinated copolymer is high, the cost will be high, and if it is low, the weather resistance and antifouling property will be insufficient.

In the present invention, a benzophenone compound or a benzotriazole compound is further added as an ultraviolet absorber to the mixture of the above-mentioned fluorine-containing copolymer and acrylic resin. UV absorbers other than benzophenone compounds or benzotriazole compounds have poor compatibility with the fluorine-containing copolymer and acrylic resin mixture, causing bleeding out from the protective film that is formed, and the effect of addition lasts for a long time. do not do. More preferably, it is a benzophenone compound.

The benzophenone compounds include 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-ethoxybenzophenone, 2-hydroxy-4.
-Butoxybenzophenone and 2,4-dihydroxybenzophenone.

The benzotriazole-based compound is 2
-(2 ^, -hydroxyphenyl) benzotriazole,
2- (2 ^, -hydroxy-5 ^, -methylphenyl) benzotriazole, 2- (2 ^, -hydroxy-5 ^, -methylphenyl) -5-carboxylic acid butyl ester benzotriazole, 2- (2 ^, -hydroxy-5) ^, -Methylphenyl) -5,6-dichlorobenzotriazole, 2- (2
^, -Hydroxy-5 ^, -methylphenyl) -5-ethylsulfone benzotriazole, 2- (2 ^, -hydroxy-
^3, - methyl ^{-5,-t-butylphenyl)} benzotriazole and 2- ^(2, - hydroxy ^{-3, 5,} - di -
Examples include t-butylphenyl) -5-chlorobenzotriazole and the like.

The amount of the benzophenone compound or benzotriazole compound added is 1 to 20 per 100 parts by weight of the mixture of the fluorine-containing copolymer and the acrylic resin.
Parts by weight, more preferably 5 to 15 parts by weight.
If the addition amount of the benzophenone compound or the benzotriazole compound exceeds 20 parts by weight, the adhesion of the protective coating to the substrate will be impaired.

In the present invention, a light stabilizer can be used together with the above-mentioned ultraviolet absorber, and specific examples of the light stabilizer include 2- (3,5-di-t-butyl-4-hydroxy). Benzyl) -2-n-butylmalonate bis (1,
2,2,6,6-pentamethyl-4-piperidyl), bis (2,2,6,6-tetramethyl-4-piperidyl)
Sebacate, bis (1,2,2,6,6-pentamethyl-4-piperidyl) sebacate, 8-acetyl-3-dodecyl-7,7,9,9-tetramethyl-1,3,8-
Examples include amine compounds such as triazaspiro (4,5) decane-2,4-dione and bis (N-octoxy-2,2,6,6-tetramethyl-4-piperidyl) sebacate.

The protective coating in the present invention is prepared by dissolving the fluorine-containing copolymer, the acrylic resin and the ultraviolet absorber in an organic solvent, and using the resulting solution as a brush, doctor blade, gravure printing, curtain flow, dipping, spray or It can be formed by coating the surface of the soft vinyl chloride resin molded body with an air knife or the like and then drying by natural drying, warm air drying, infrared ray drying or the like.
The protective coating preferably has a thickness of 1 to 100 μ, more preferably 5 to 30 μ.

As the organic solvent, toluene, xylene,
Aromatic hydrocarbons such as Solvesso, ethyl acetate, acetate such as butyl acetate, acetone, methyl ethyl ketone,
Ketones such as methyl isobutyl ketone, n-butanol,
alcohol such as i-propanol, methyl cellosolve,
Cellosolve such as n-butyl cellosolve is preferably used. A solvent having a boiling point of 100 ° C. or lower is preferable. In addition, an antistatic agent, a leveling agent, a pigment, a dispersion stabilizer and the like may be added to the resin solution for forming a protective film.

[0021]

EXAMPLES The present invention will be described in more detail with reference to the following examples and comparative examples. <Examples 1 to 6> The protective film forming compositions having the compositions shown in Table 1 were dissolved in 200 parts by weight of methyl ethyl ketone to prepare coating solutions 1 to 6. Using a gravure coater on one side of a 1.3 mm-thick sheet molded from a soft vinyl chloride resin containing 80 parts by weight of dioctyl phthalate as a plasticizer per 100 parts by weight of polyvinyl chloride, the solution for forming a protective film is formed into a film. Is painted to be 15μ, 80 ℃
It was dried by heating for 2 minutes.

[0022]

[Table 1]

In Table 1, V-1, V-2 ---- U-3
Etc. are as follows. V-1: VdF / CTFE = 82.5 / 17.5 (mol%)
The polymer having a polystyrene-reduced number average molecular weight (hereinafter referred to as Mn) of 54000 measured by GPC is V-2: VdF / CTFE = 85/15 (mol%),
Copolymer with Mn of 48000 V-3: VdF / CTFE = 75/25 (mol%),
Copolymer with Mn of 45000 V-4: VdF / CTFE = 80/20 (mol%),
Copolymer with Mn of 78000

A-1: Polymethylmethacrylate having Mn of 55000 (Tg = 105 ° C.) A-2: Copolymer of methylmethacrylate / ethylmethacrylate = 80/20 (weight ratio) (Tg = 92 ° C.).
Mn; 38000. A-3: Copolymer of methyl methacrylate / cyclohexyl methacrylate / butyl methacrylate = 75/20/5 (weight ratio) (Tg = 90 ° C.). Mn; 5900
0.

U-1: Mark 1 manufactured by ADEKA ARGUS CORPORATION
413 (benzophenone-based compound) U-2: Ciba Geigy Ltd. Tinuvin P (benzotriazole-based compound) U-3: ADEKA ARGUS CORPORATION mark LA51 (benzophenone-based compound)

The following physical properties of the protective film thus obtained were evaluated, and the results are shown in Table 2. (1) Blocking property: 10 between coating layer and untreated surface
After blocking with 0 g / cm ² and maintaining at 80 ° C. for 24 hours, the blocking property was evaluated. Result: ○ Blocking free,
X Blocking (2) Cross-cut peeling: 100 cuts were made in a 1 cm ² square, and the residual ratio when peeled with cellophane tape was shown. Further, the peeling residual ratio after immersing the notched coated plate in boiling water for 1 hour and the appearance of the coating film after boiling water are also shown. (3) Transfer amount of plasticizer: The protective coat layer of the treated sheet and the untreated sheet were overlapped, and the load was 300 g / 80 ° C. for 24 hours.
After holding at cm ² , the weight gain was measured. (4) Contamination resistance: A sheet was attached to the wall of a road with heavy traffic in Minato-ku, Nagoya, and exposed for 6 months. The 60 ° gloss retention before and after that was measured. (5) Weather resistance; irradiation with a sunshine weather meter 1
The test was conducted for 600 hours under the conditions of 20 minutes of spraying, 18 minutes of spraying, and a black panel temperature of 63 ° C., and the change in 60 ° gloss was measured.

Comparative Example 1 40 parts by weight of a copolymer having a composition of VdF / tetrafluoroethylene / hexafluoropropylene = 75/20/5 (mol%), Mn of 55000, and the acrylic resin of A-1 above. A mixture of 60 parts by weight and 5 parts by weight of the U-1 UV absorber was dissolved in 200 parts by weight of methyl ethyl ketone to prepare a solution for forming a protective film, which was then operated in the same manner as in the above-mentioned Examples to form a soft vinyl chloride resin molding. Was applied to the surface of.

<Comparative Example 2> As the acrylic resin, methyl methacrylate / ethyl acrylate = 60/40
Copolymer (Mn) of 37000 (weight ratio) (T
g = 46 ° C.) The protective film-forming solution obtained in the same manner as in Example 1 was applied to the surface of the soft vinyl chloride resin molded product. The results of measuring the physical properties of the protective coatings prepared in Comparative Examples 1 and 2 are also shown in Table 2 below.

[0029]

[Table 2]

[0030]

The soft vinyl chloride resin molding of the present invention is
It has a fluorine-containing copolymer with excellent weather resistance as a constituent component, and a protective film containing an ultraviolet absorber is formed with good adhesion, so it has excellent stain resistance and weather resistance, and is used outdoors for agricultural purposes. Suitable for films, sheets and the like.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Ryusei Nishio 1 1 Funami-cho, Minato-ku, Nagoya, Aichi Toagosei Synthetic Chemical Industry Co., Ltd. Nagoya Research Institute (72) Inventor Akito Iida Nagoya, Aichi 1 Toago Synthetic Chemical Industry Co., Ltd., Nagoya Research Institute, Minami-ku Funami-cho (72) Inventor Hiroshi Inukai 1 Touna Synthetic Chemical Industry Co., Ltd. Nagoya Research Institute, Minami-ku, Aichi Prefecture Nagoya City Within

Claims (1)

[Claims] 1. (a) Vinylidene fluoride monomer unit 90
~ 75 mol% and chlorotrifluoroethylene monomer unit 10 to 25 mol%, a fluorine-containing copolymer,
(B) Consisting of (meth) acrylic acid ester-based resin having a glass transition temperature of 60 ° C. or higher and (c) benzophenone-based compound or benzotriazole-based compound, per 100 parts by weight of the total amount of the components (a) and (b). A soft vinyl chloride resin molded product having a protective coating formed by a composition containing 1 to 20 parts by weight of the component (c).