JP3214008B2 - Manufacturing method of surface hardened resin plate - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a resin plate subjected to a surface hardening treatment. More specifically, the present invention relates to a method for producing a surface-cured resin plate which can be installed in equipment for continuously producing a resin plate and has excellent surface condition, hardness, and adhesion of a hard coat layer.

[0002]

2. Description of the Related Art As a method for producing a surface-cured resin plate, there are a method of applying and curing a treatment liquid by, for example, a spray, a roller, a brush coating, and the like, and a method of dipping a substrate in the treatment liquid and then curing. Among these methods, the method of immersing the substrate in the treatment liquid is an effective method for a substrate having a complicated shape or a substrate having a large surface area.

As a coating method using a roller, for example, JP-A-60-131224 discloses a method in which a scratch-resistant resin film is formed in advance on a roll surface, and a plate-like thermoplastic resin discharged from a plasticizing extruder is discharged. A method is described in which the film is transferred to the resin from the roll surface by pressing the resin on the resin.

In Japanese Patent Publication No. 56-53488, a resin material is continuously injected into a space formed by a pair of a single-sided mirror-polished stainless steel endless belt and a gasket, polymerized, and continuously polymerized. A method is described in which an abrasion-resistant resin film is previously formed on the endless belt in an apparatus for manufacturing a plate, and a resin material is injected and transferred during polymerization.

Japanese Patent Application Laid-Open No. 61-161178 describes a method of laminating a film coated with an ultraviolet paint on an object to be coated having a specific cross-sectional shape with a roller, and then irradiating the film with ultraviolet light to peel off the transfer film.

[0006]

SUMMARY OF THE INVENTION Among the above prior arts,
In the method of dip-coating the substrate, the surface condition is deteriorated due to dust and dirt being mixed in the treatment step, or vibration and speed difference at the time of lifting after dipping. In addition, a large amount of treatment liquid is required for the immersion treatment.

[0007] The methods disclosed in JP-A-60-131224 and JP-A-61-161178 have poor adhesion between a scratch-resistant resin coating and a plate-like thermoplastic resin,
The abrasion-resistant resin film is easily peeled off.

In the method disclosed in Japanese Patent Publication No. 56488/1981, the apparatus itself for producing a resin plate by continuous polymerization is a large-scale apparatus and requires a large investment in equipment.

In the flow coating, spraying, and roller methods, etc., a pretreatment of the substrate is required, and since the substrate is cured by irradiating ultraviolet rays in the air, the hardness is reduced due to oxygen inhibition.

[0010]

Means for Solving the Problems In view of the above problems, the present inventors have conducted intensive studies. As a result, an extremely excellent surface hardening treatment can be achieved by laminating a tape coated with an ultraviolet curable resin under specific conditions. It was found that a plate was obtained, and the present invention was completed.

That is, the present invention provides a method in which a transfer tape obtained by applying an ultraviolet-curable resin to one surface of a transparent film is pressure-bonded to a resin plate by a roll, and cured by irradiating ultraviolet rays from above the transfer tape. Forming a cross-linked cured layer on the surface of the resin plate, in a method of manufacturing a surface-cured resin plate,
When the temperature of the bonding roll surface when bonding the transfer tape is 80
A method for producing a surface-hardened resin plate, wherein the temperature is at least ° C.

The transparent film used in the present invention includes:
A material that transmits ultraviolet light is preferable, and a PET film, a nylon film, a polycarbonate film, an acrylic film, a polyolefin film such as polypropylene,
Examples include cellulose-based films such as diacetylcellulose and triacetylcellulose, and polyvinylidene chloride-based films. Among them, a PET film and a nylon film are preferable from the viewpoint of surface smoothness and ultraviolet transmittance.

As the UV-curable surface curing agent used in the present invention, a crosslinkable resin material having two or more acryloyl groups or methacryloyl groups in one molecule is preferably used. Crosslinkable resin materials include trimethylolpropane triacrylate or trimethacrylate, trimethylolethane triacrylate or trimethacrylate, pentaglycerol triacrylate or trimethacrylate, pentaerythritol triacrylate or trimethacrylate, pentaerythritol tetraacrylate or tetramethacrylate, glycerin Triacrylate or trimethacrylate, dipentaerythritol triacrylate or trimethacrylate, dipentaerythritol tetraacrylate or tetramethacrylate, dipentaerythritol pentaacrylate or pentamethacrylate, dipentaerythritol hexaacrylate or hexamethacrylate Relate, tripentaerythritol tetraacrylate or tetramethacrylate, tripentaerythritol pentaacrylate or pentamethacrylate, 2,2-bis (4-acryloxydiethoxyphenyl) propane, 2,2-bis (4-methacryloxyethoxyphenyl) propane Polyacrylates or polyhydric alcohols such as diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, tetraethylene glycol dimethacrylate, tripentaerythritol hexaacrylate or hexamethacrylate, tripentaerythritol heptaacrylate or heptamethacrylate Methacrylate: malonic acid / trimethylolethane / acrylic acid or methacrylate Sulfonic acid, malonic acid / trimethylolpropane / acrylic acid or methacrylic acid, malonic acid / glycerin / acrylic acid or methacrylic acid, malonic acid / pentaerythritol / acrylic acid or methacrylic acid, succinic acid / trimethylolethane / acrylic acid or methacrylic acid Acid, succinic acid / trimethylolpropane / acrylic acid or methacrylic acid, succinic acid / glycerin / acrylic acid or methacrylic acid, succinic acid / pentaerythritol / acrylic acid or methacrylic acid, adipic acid / trimethylolethane / acrylic acid or methacrylic acid , Adipic acid / trimethylolpropane / acrylic acid or methacrylic acid, adipic acid / pentaerythritol / acrylic acid or methacrylic acid, adipic acid / glycerin / acrylic or methacrylic acid, glutaric acid / trimethylic acid Tyrolethane / acrylic acid or methacrylic acid, glutaric acid / trimethylolpropane / acrylic acid or methacrylic acid, glutaric acid / glycerin / acrylic acid or methacrylic acid, glutaric acid / pentaerythritol / acrylic acid or methacrylic acid, sebacic acid / trimethylolethane / Acrylic acid or methacrylic acid, sepasic acid / trimethylolpropane / acrylic acid or methacrylic acid, sepasic acid / glycerin / acrylic acid or methacrylic acid, sebacic acid / pentaerythritol / acrylic acid or methacrylic acid, fumaric acid / trimethylolethane / Acrylic or methacrylic acid, fumaric acid / trimethylolpropane / acrylic or methacrylic acid, fumaric acid / glycerin / acrylic or methacrylic acid, fumaric acid / pentaerythritol / Crylic or methacrylic acid, itaconic acid / trimethylolethane / acrylic or methacrylic acid, itaconic acid / trimethylolpropane / acrylic or methacrylic acid, itaconic acid / pentaerythritol / acrylic or methacrylic acid, maleic anhydride / trimethylol Saturated or unsaturated polyester polyacrylates or polymethacrylates by a combination of compounds such as ethane / acrylic acid or methacrylic acid, maleic anhydride / glycerin / acrylic acid or methacrylic acid: tolylene diisocyanate, xylylene diisocyanate, diphenylmethane diisocyanate, isophorone diisocyanate, Hexamethylene diisocyanate, dicyclohexylmethane diisocyanate, or aromatic diisocyanate compounds Diisocyanate compound obtained by hydrogenating the isocyanates (e.g. hydrogenated xylylene diisocyanate, diisocyanate compounds such as hydrogenated diphenylmethane diisocyanate) triphenylmethane triisocyanate, such as dimethylene triphenyl triisocyanate 2
An isocyanate-containing compound such as a polyisocyanate compound obtained by multiplying a trivalent or trivalent polyisocyanate compound or a diisocyanate compound and an acrylic monomer having active hydrogen, for example, 2-hydroxyethyl acrylate or methacrylate, 2-hydroxypropyl acrylate or Urethane acrylate obtained by reacting methacrylate, 2-hydroxy-3-methoxypropyl acrylate or methacrylate, N-methylolacrylamide or methacrylamide, N-hydroxyacrylamide or methacrylamide with 2 mol or more per isocyanate molecule in a conventional manner: Other tris (2-hydroxyethyl) isocyanuric acid triacrylate or trimethacrylate Examples thereof include a diisocyanate compound such as phenylmethane diisocyanate) a polyvalent or trivalent polyisocyanate compound such as triphenylmethane triisocyanate and dimethylene triphenyl triisocyanate, or a polyisocyanate compound obtained by multiplying a diisocyanate compound. Acrylic monomers having an isocyanate-containing compound such as an isocyanate compound and active hydrogen, for example, 2-hydroxyethyl acrylate or methacrylate, 2-hydroxypropyl acrylate or methacrylate,
Urethane acrylate obtained by reacting -hydroxy-3-methoxypropyl acrylate or methacrylate, N-methylolacrylamide or methacrylamide, N-hydroxyacrylamide or methacrylamide with 2 mol or more per isocyanate molecule by a conventional method: other tris ( Examples thereof include triacrylate or trimethacrylate of (2-hydroxyethyl) isocyanuric acid, and those containing urethane acrylate as a main component are preferable from the viewpoint of surface hardness and weather resistance. In order to improve the weather resistance or impart various functions to the surface hardener, additives such as an antistatic agent, an antifogging agent, an antioxidant, an ultraviolet absorber, and a coloring agent can be added.

As a method of applying the ultraviolet curable resin to the transparent film, there are roll coating, spray coating, brush coating, and the like, but the roll coating method is preferably used.

The resin plate to be subjected to the surface hardening treatment is not particularly limited, but may be a resin plate of an acrylic resin, a polycarbonate resin, a polystyrene, a styrene-acryl copolymer, an acrylonitrile-styrene copolymer, etc. However, an acrylic resin plate and a polycarbonate resin plate are preferred.

When bonding the transfer tape and the resin plate, the temperature of the resin plate may be at least room temperature and is not particularly limited, but the surface temperature of the bonding roll is at least 80 ° C. When the surface temperature is lower than 80 ° C., the adhesiveness of the ultraviolet curable resin to the resin plate decreases. If the surface temperature of the laminating roll is unnecessarily high, the transfer tape or the resin plate may be deformed and the processing operation may become difficult. Therefore, the surface temperature is usually preferably 350 ° C. or lower. A rubber roll or a metal roll is generally used as the bonding roll.

In the present invention, the moving speed of the resin plate when laminating the transfer tape and the resin plate can be appropriately determined according to the surface temperature of the laminating roll, but when the roll surface temperature is 80 to 350 ° C. Usually, the moving speed of the resin plate is
0.1 to 10 m / min.

The resin plate and the transfer tape are crimped as described above,
After bonding, the transfer tape is irradiated with ultraviolet light to cure the ultraviolet-curable resin, and the transfer tape is peeled off to obtain a surface-cured resin plate.

For the ultraviolet irradiation, a general ultraviolet irradiator such as a low-wavelength UV lamp, a halogen lamp, a xenon lamp, a metal halide lamp, a krypton arc lamp, a xenon flash lamp, and a flash UV lamp can be used.

[0020]

According to the method of the present invention, the physical properties of the conventional surface-hardened resin plate are greatly improved. A resin plate to be subjected to surface hardening treatment, especially a resin plate extruded from an extruder, is immediately pasted with a film coated with an ultraviolet curable resin,
By curing, there is no contamination of dust, dirt and the like, and a surface-cured resin plate having an excellent surface can be obtained. The cured resin plate surface is transferred to the film surface, so there is no mold such as rolls, and the surface condition is greatly improved.Because it is covered with the film and irradiated with ultraviolet light, there is no decrease in hardness due to oxygen inhibition. Very good hardness can be obtained.

[0021]

The following examples are provided to further illustrate the method of the present invention, but the invention is not necessarily limited thereto. In addition, the performance evaluation of the surface hardened resin plate was performed based on the following criteria.

Hardness: A steel wool test (10 reciprocations under a load of 1 kg) was performed to observe the surface condition. A: There is no scratch. B: About 10 scratches. C: Dozens of scratches. D: Many scratches. E: Countless scratches (hardness of original plate before surface hardening treatment).

Adhesion: Cross hatches at 1 mm intervals
The percentage of the unpeeled part when the cellophane tape was peeled was evaluated.

Examples 1 to 8 An ultraviolet curable resin (Dainippon Ink, Unidick 17-806) is applied on one side of a PET film on the surface of an acrylic resin plate (Sumipex E, manufactured by Sumitomo Chemical Co., Ltd.). The other side is pressure-bonded (8 kg / cm ² ) to the transfer tape that has been release-treated using a bonding roll having the surface temperature shown in Table 1.
Paste. UV irradiation from above the transfer tape (UVC-3533-1HOLC3-MX01, manufactured by Ushio Inc.)
Irradiation conditions: lamp output: 120 W, distance: 12 cm, conveyor speed: 0.5 m / min), the ultraviolet curable resin was cured, and the transfer tape was peeled off to obtain a surface cured resin plate. As shown in Table 1, the results were excellent in both hardness and adhesion.

Comparative Examples 1-2 A surface-cured resin plate was obtained in the same manner as in Example 1, except that the conditions for laminating the acrylic resin plate and the transfer tape were as shown in Table 1. As shown in Table 1, the results were inferior due to inferior adhesion and warping of the resin plate.

[0026]

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) B32B 27/00-27/42 C08J 7/04

Claims (2)

(57) [Claims] 1. A transfer tape in which an ultraviolet curable resin is applied to one side of a transparent film, is pressure-bonded to a resin plate with a roll, and
The method of manufacturing a surface-cured resin plate by forming a cross-linked cured layer on the surface of the resin plate by irradiating ultraviolet rays from above the transfer tape to cure the surface of the resin plate, the surface of the bonding roll when bonding the transfer tape. A temperature of 80 ° C. or higher. 2. The method for producing a surface-cured resin plate according to claim 1, wherein the ultraviolet-curable surface curing agent contains urethane acrylate as a main component.