JPS6350066B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for continuously manufacturing a textured decorative material by mechanically embossing an EB-curable material and simultaneously curing it in an electron beam (hereinafter referred to as EB) irradiation machine.

Mechanical embossing using die rolls is currently widely used. For example, doubling embossed sheets, which are made by laminating a transparent PVC or PP (polypropylene) film onto a wood-grained PVC (polyvinyl chloride) film, and mechanically embossing the wood grain on the surface with a die roll, are mostly used in the cabinets of home appliances. There is. In addition, embossed steel sheets, which are made by coating decorative steel sheets with PVC sol clear and mechanically embossing them with die rolls after firing, are widely used in building materials such as partition doors and cabinets for home appliances. In either case, a textured roll is pressed onto the heat-softened layer to shape the texture, so it is difficult to form fine texture, and since it is limited to thermoplastic resins, there are limits to the surface properties.

The inventors of the present invention have attempted to improve the above, and as a result of various researches, the inventors have found that by bringing an EB-curable liquid material into contact with a mold roll to form irregularities, and then curing the liquid material by irradiating EB, The inventors have discovered that the above improvements can be made and have completed the present invention.

That is, in the present invention, an EB curable liquid material is applied to a base material, and unevenness is formed by contacting the substrate in a wet state with an uneven roll in an EB irradiation machine, and then EB irradiation is performed to instantly harden the liquid material. Finally, the uneven cured product is removed from the mold roll.

According to the present invention, fine irregularities can be formed with good reproducibility because the material is brought into contact with the irregularity roll in a wet state, and irregularities with good surface physical properties can be obtained because of EB curing.

Hereinafter, the present invention will be explained in detail using the drawings. FIG. 1 schematically shows an example of an apparatus used in the method of the present invention. First, as shown in FIG. Apply. EB by conveyor
Contact with the feed type roll 5 in the irradiation machine 4,
Shape the unevenness of the mold roll. While in contact with the mold roll 5, EB6 is irradiated to instantly harden the liquid.
During transportation, the uneven cured product is removed from the mold roll,
Transport it outside from the EB irradiation machine 4. Furthermore, if necessary, preheating is performed using the heater 7 or postheating is performed using the heater 8 before or after EB irradiation.

In the above, the base material can be any base material such as metal plate, metal sheet, wood board, inorganic board, plastic film, paper, etc. Decorative film or decorative board with printing on the surface may also be used, but EB low temperature cure is particularly suitable. It is desirable to use a plastic film with a softening point of 200°C or less to take advantage of the characteristics of . Furthermore, when using a permeable base material such as paper, it is desirable to prevent penetration into the base material.

EB curable liquids are prepolymers or oligomers having ethylenically unsaturated bonds in their molecules, such as unsaturated polyesters, polyester acrylates, epoxy acrylates, urethane acrylates, polyether acrylates, polyol acrylates, various acrylates such as melamine acrylates, etc. , one or more of various methacrylates such as polyester methacrylate, epoxy methacrylate, urethane methacrylate, polyether methacrylate, polyol methacrylate, and melamine methacrylate, and a monomer having an ethylenically unsaturated bond in the molecule, such as styrene, α - Styrenic monomers such as methylstyrene; methyl acrylate,
Acrylic acid esters such as 2-ethylhexyl acrylate, methoxyethyl acrylate, butoxyethyl acrylate, butyl acrylate, methoxybutyl acrylate, phenyl acrylate; methyl methacrylate, ethyl methacrylate, propyl methacrylate, methoxy methacrylate Methacrylic acid esters such as ethyl, ethoxymethyl methacrylate, phenyl methacrylate, and lauryl methacrylate; Unsaturated carboxylic acid amides such as acrylamide and methacrylamide; Acrylic acid 2-(N,
N-dimethylamine)ethyl, methacrylic acid 2-
(N,N-dimethylamino)ethyl, 2-(N,N-dibenzylamino)ethyl acrylate, (N,N-dimethylamino)methyl methacrylate, 2-(N,N-diethylamino)propyl acrylate, etc. Substituted amino alcohol esters of unsaturated acids of acrylate,
Polyfunctional compounds such as ethylene glycol dimethacrylate, propylene glycol dimethacrylate, diethylene glycol dimethacrylate, and/or polyol compounds having two or more thiol groups in the molecule, such as trimethylolpropane trithioglycolate, trimethylolpropane trithio It can be made by mixing propionate, bentaerythritol tetrathioglycolate, etc.

There are no particular restrictions when making the above EB curing material, and it can be mixed as desired, but in order to provide normal coating suitability, the above prepolymer or oligomer should be added in an amount of 5% by weight or more, the above monomer and/or the above It is preferable that the polythiol content be 95% by weight or less.

A polymerization inhibitor such as hydroquinone, hydroquinone monomethyl ether, or benzoquinone can also be added to the EB-curable material as a stabilizer to prevent it from curing before EB irradiation.

As a method for applying the EB cured material obtained as described above to a base material, known coating methods such as a roll coater, curtain flow coater, Miyabar coater, gravure roll coater, and air knife coater can be used. In addition, the amount of coating varies depending on the coating method and electron beam irradiation machine, but 1
~100μ is desirable.

The EB curing material applied to the base material is heated in a nitrogen atmosphere using a low-energy electron accelerator, such as an electrocurtain manufactured by Energy Science Industries.
CB20d50/30 or NP made by Otsutodueur
- Can be cured while being continuously wound using ESH150 etc. The amount of EB irradiation at this time is sufficient to be absorbed enough to harden the electron beam curable material.
Usually 0.5~30 Mrad.

As the mold roll, a normal uneven roll can be used, but since the EB that has passed through the base material and the coated material hits the mold roll, heat resistance is required, and a water-cooled roll is preferable. Furthermore, since the material is shaped in a wet state, it is possible to form the uneven pattern with good reproducibility even with a mold roll whose uneven pattern has an accuracy of less than 10 μm.

Depending on the type of liquid material, coating thickness, and EB irradiation method, preheating or postheating may be performed before or after EB irradiation. For example, when adding a small amount of low-boiling point diluent to a liquid to improve its suitability for coating, it is desirable to preheat before EB irradiation to volatilize the diluent, and the curing by EB irradiation is insufficient. In Case of,
Post-heating can be performed after EB irradiation to further promote crosslinking. Furthermore, in order to facilitate removal of the uneven cured material from the mold roll, the surface of the coated material may be further hardened by preheating.

Hereinafter, the present invention will be explained in more detail with reference to Examples. Note that "parts" in the following text indicate "parts by weight."

Example 1 The following composition was uniformly applied to a thickness of 50 μm using a curtain flow coater onto a 50 μm soft vinyl chloride film with wood grain printing.

Urethane acrylate (manufactured by Nippon Gosei Co., Ltd.)
XP7000B) 30 parts oligoester acrylate (manufactured by Toagosei Co., Ltd.)
Aronix M7300) 70 parts This coated material was transported in a wet state into a scanning type electron beam irradiation machine, and after contacting it with a convex wood grain conduit roll to form a concave part, it was heated at 5 Mrad while in contact with a mold roll. The dose was irradiated from the substrate side and cured.

The cured product was removed from the mold roll and transported outside the electron beam irradiation machine.

However, each process is all done inline at 10m/min.
produced at a speed of By this method, we obtained a doubling embossed sheet with fine surface embossed wood grain conduits and excellent surface properties.

Example 2 The following composition was uniformly coated to a thickness of 100μ on a 20μ polyethylene film using a reverse roll coater.

Polyester acrylate (Mitsui Toatsu Co., Ltd. OLESTAR After being brought into contact with the cylinder to form irregularities, it was left in contact with the cylinder in a nitrogen atmosphere.
By 150Kev, 5mA curtain electron beam
It was irradiated with a dose of 2 Mrad and cured.

The cured product was removed from the mold and transported outside the electron beam irradiation machine. However, each process is all inline 10
It was manufactured at a speed of m/min. By this method, linear Fresnel lens sheets were obtained continuously with high precision and at low cost.

Example 3 The following composition was uniformly coated to a thickness of 40μ on a 12μ polyester film using a curtain flow coater.

Epoxy acrylate (Lipoxy VR90 manufactured by Showa Kobunshi Co., Ltd.) 60 parts Dipentaerythritol hexaacrylate (DPHA manufactured by Nippon Kayaku Co., Ltd.) 40 parts Methyl ethyl ketone (MEK) 15 parts After vaporizing MEK with a preheater,
The material was transported into an electron beam irradiation machine and brought into contact with a leather-patterned convex roll to form concave parts, and then was cured by irradiating a dose of 5 Mrad from the base material side while in contact with a mold roll. The cured product was removed from the mold roll, transported outside the electron beam irradiation machine, and the polyester film was peeled off. However, all steps were performed in-line at a speed of 30 m/min. By this method, a leather patterned sheet was obtained at low cost.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram illustrating the outline of an apparatus used in the method of the present invention. 1... Base material, 2... Coating device, 3... EB curable liquid, 4... EB irradiation machine, 5... uneven roll, 6... EB, 7... heater, 8... heater.

Claims (1)

[Scope of Claims] 1. A continuous uneven molding method using electron beam irradiation, which is characterized by including the following steps. (a) Continuously applying a liquid material having electron beam curability to the substrate; (b) Transferring the applied material into an electron beam irradiation machine and bringing it into contact with a textured roll in the irradiation machine to apply the above coating. (c) While the coated article is in contact with the mold roll, the coated article is irradiated with an electron beam to continuously cure the coated article to form an uneven cured product; (d) A step in which the uneven cured product is continuously removed from the mold roll and transported outside the electron beam irradiation machine. 2. The uneven molding method according to claim 1, which includes a step of peeling the uneven cured product from the base material after the step (d). 3. Claim 1 in which the uneven pattern of the mold roll in the step has a height or interval finer than 10μ.
The uneven molding method according to item 1 or 2. 4. The uneven molding method according to claims 1, 2, and 3, wherein the base material has a softening point of 200°C or less. 5. The uneven molding method according to claim 1, 2, 3, or 4, which includes a heating step before the step (b) and/or after the step (c).