JPH0142748B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of forming a high-performance mirror surface by combining an electron beam (hereinafter simply referred to as EB) hardening material and a material having a mirror surface.

A mirror surface is a design that is widely required for high-end products, and is required for ultra-high-gloss products on the surfaces of high-grade decorative laminates (melamine decorative laminates, daptop decorative laminates, etc.) for building materials, packaging materials, and interfaces for commercial printing applications. ing. Current mirror finishing methods include calendar roll pressing, pressing with a mirror plate, film adhesion, and wet lamination with a mirror material, but each has its own problems. Calendar roll press is a method of creating a mirror surface by pressing under high pressure using a roll having a mirror surface, but only an insufficient mirror surface design can be obtained. Pressing with a mirror plate is a method used in the manufacturing process of thermosetting resin decorative boards to thermoset and create a mirror surface by pressing resin-impregnated paper with a mirror plate at high temperature and pressure, resulting in a good mirror surface. However, productivity is poor because it requires single-wafer pressing. Film lamination is a method widely used at present, in which a mirror surface is obtained by laminating a thin transparent film (such as polypropylene) onto a printed matter, but only an insufficient mirror surface design can be obtained. Wet lamination with mirror material is a method of making the paper's surface coated resin mirror-like by wet-laminating a film with good surface gloss and resin-coated paper, resulting in a good mirror-like design. However, since it is wet lamination, the drying and curing of the resin is slow, and the base material is limited to breathable materials such as paper.

In view of the above-mentioned drawbacks, the inventors of the present invention have made extensive studies and found that by wet laminating a mirror material and a base material using an EB curable resin,
The inventors have found that the above drawbacks can be solved and have completed the present invention.

That is, the present invention provides a base material (or mirror material)
Applying an EB curable liquid material to the surface, then heating the liquid material, laminating it with a mirror material (or base material), curing the liquid material with EB, and finally peeling off the cured material from the mirror material. This makes the surface of the cured product mirror-like.

According to the present invention, since the base material and the mirror material are wet laminated, a high mirror surface can be obtained, and since the material is cured by EB, a drying process is not necessary, and any material can be used as the base material. Therefore, significant improvements in design and workability are achieved, and the range of application of the product can be expanded.

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. In FIG. 1, a liquid substance 3 having EB curability is applied onto a substrate 1 using a coating apparatus 2. After that, the mirror material 4 is preheated by a heater 6 before EB irradiation, and then the mirror material 4 is laminated with the mirror surface facing the base material 1, the liquid material is hardened by the EB irradiation machine 5, and finally the mirror material 4 is peeled off. Furthermore, if necessary, preheating may be performed using the heater 7 or postheating may be performed using the heater 8 after EB irradiation.

In FIG. 2, a liquid substance 3 having EB curability is applied onto a mirror material 4 using a coating device 2, and then preheated by a heater 6. After that, a base material 1 is laminated, and a liquid substance 3 is applied by an EB irradiation machine 5. harden,
Finally, the cured product is peeled off from the mirror material. In this case as well, if necessary, preheating or postheating may be performed using the heaters 7 and 8. In the above, the mirror material 4 can be supplied and collected in a rolled form, and can also be used continuously in the form of an endless belt. Further, there is no problem in producing the film in single wafers, not in a continuous production line as shown in FIGS. 1 and 2, but in each process off-line. Furthermore, if necessary, the cured product may be peeled off from the base material at the end. By performing preheating in the above step, the fluidity of the EB curable liquid improves, and the
Can increase curing reactivity by EB. Furthermore, it is also possible to control the film thickness of the liquid material. Further, in order to improve the coating suitability of the liquid by adding a small amount of a low-boiling diluent to the liquid, it is desirable to preheat the liquid before EB irradiation to volatilize the diluent. In particular, since the liquid material is laminated, it is possible to prevent air from entering before lamination. That is, during EB irradiation, curing is inhibited by oxygen in the air between the laminate and the liquid material. However, since the fluidity of the liquid material is good due to preheating, the liquid material and the laminate come into close contact with each other, so that the above-mentioned mixing of oxygen in the air can be avoided.

Here, whether to apply the EB curable liquid to the base material or the mirror material, or which side to irradiate EB from, depends on the properties of the base material and the mirror material (thickness, suitability for winding, resin applied to the base material). (seepage, etc.) can be selected. For example, if the base material is thick and EB transmission is insufficient, a mirror material can be laminated on top.
EB should be irradiated from above, and if the mirror material is hard like a metal plate or the base material is heavily soaked with resin like paper, the base material should be laminated from above. EB should be irradiated from above.

Now, here, the base material can be any material such as metal plate, metal sheet, wooden board, plastic film, paper, inorganic board, etc., and decorative film or decorative board with printing on the surface may also be used, but especially EB A plastic film having a softening point of 200° C. or less can be used to take advantage of the low-temperature cure characteristics.

Materials used as mirror materials include metal plates, metal sheets, plastic films, resin coated paper, metallized films, metallized paper, and glass. Plastic films having softening points below can be used.

EB curable materials that can be cured by EB irradiation include prepolymers or oligomers having ethylenically unsaturated bonds in their molecules, such as unsaturated polyesters, polyester acrylates, epoxy acrylates, urethane acrylates, polyether acrylates, polyol acrylates, melamine acrylates, etc. acrylates, polyester methacrylate, epoxy methacrylate, urethane methacrylate, polyether methacrylate, polyol methacrylate, melamine methacrylate, etc., and a monomer having an ethylenically unsaturated bond in the molecule, e.g. Styrenic monomers such as , styrene, and α-methylstyrene; acrylic acids such as methyl acrylate, 2-ethylhexyl acrylate, methoxyethyl acrylate, butoxyethyl acrylate, butyl acrylate, methoxybutyl acrylate, and phenyl acrylate. Esters; Methacrylic acid esters such as methyl methacrylate, ethyl methacrylate, propyl methacrylate, methoxyethyl methacrylate, ethoxytityl methacrylate, phenyl methacrylate, and lauryl methacrylate; Unsaturated carboxylic acid amides such as acrylamide and methacrylamide; Acrylic acid 2-(N,N-dimethylamino)
Ethyl, 2-(N,N-dimethylamino)ethyl methacrylate, 2-(N,N-dibenzylamino)ethyl acrylate, (N,N-dimethylamino)methyl methacrylate, 2-(N, N
Substituted amino alcohol esters of unsaturated acids such as -diethylamino)propyl; ethylene glycol diacrylate, propylene glycol diacrylate, neopentyl glycol diacrylate, 1,6-hexanediol diacrylate,
Polyfunctional compounds such as diethylene glycol diacrylate, triethylene glycol diacrylate, dipropylene glycol diacrylate, ethylene glycol dimethacrylate, propylene glycol dimethacrylate, diethylene glycol dimethacrylate, and/or having two or more thiol groups in the molecule It can be prepared by mixing polythiol compounds such as trimethylolpropane trithioglycolate, trimethylolpropane trithiopropionate, and pentaerythritol tetrathioglycolate.

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, known coating methods such as a roll coater, curtain flow coater, Miyabar coater, gravure roll coater, and air knife coater can be used. Alternatively, it must be selected depending on the columnar shape of the mirror material. The coating amount varies depending on the coating method and electron beam irradiation machine, but is preferably 1 to 100 μm.

The EB hardening material interposed between the base material and the mirror material is continuously wound in a nitrogen atmosphere using a low-energy electron acceleration, such as an electrocurtain CB20d50/30 manufactured by Energy Science Industry Co., Ltd. or NP-ESH150 manufactured by Otsuto Duel Co., Ltd. It can be cured while being removed. The EB irradiation dose at this time may be an absorbed dose sufficient to harden the EB curing material, and is usually 0.5 to 30 Mrad.

Depending on the type of liquid material, coating thickness, and EB irradiation method, preheating or postheating may be performed twice before EB irradiation, and then again after EB irradiation. For example, if a heating process is performed after the lamination process and before EB irradiation,
Furthermore, it has the effect of smoothing out the liquid. Also,
If curing by EB irradiation is insufficient, post-heating can be performed after EB irradiation to further promote crosslinking.

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 coated on a 12μ polyester film to a thickness of 5μ using a gravure roll coater.

Urethane acrylate (manufactured by Nippon Gosei Co., Ltd.)
XP7000B) 30 parts oligoester acrylate (manufactured by Toagosei Co., Ltd.)
Aronix M7300) 70 copies This coated material was laminated in a wet state onto the printed paper surface of a 3 x 6 size wood grain printed paper laminated board, and then exposed using a scanning electron beam irradiation machine.
A dose of 5 Mrad was applied over the polyester film. After the coating material had hardened, the polyester film was peeled off, and a wood grain printed plywood with a mirror surface was obtained.

Example 2 The following composition was coated to a thickness of 40 μm on 20 μm Al-deposited paper using a reverse roll coder.

Polyester acrylate (Mitsui Toatsu Orestar
By 150Kev, 5mA curtain electron beam
A dose of 2 Mrad was irradiated. Thereafter, when the cellophane film was peeled off, ultra-high gloss Al-deposited paper was obtained. However, all manufacturing was done in-line at a speed of 30 m/min.

Example 3 The following composition was coated to a thickness of 40μ on a 100μ stainless steel sheet 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 volatilizing MEK with a preheater, label inside the liquid detergent container. The printed paper was laminated with the printed side in between. The printed paper was then irradiated with a dose of 5 Mrad using a scanning electron beam irradiation machine. After curing, when the cured product was peeled off from the stainless steel sheet, an ultra-high gloss label was obtained.

[Brief explanation of drawings]

FIG. 1 and FIG. 2 are schematic diagrams each 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... Mirror material, 5... EB irradiation machine,
6... Heater, 7... Heater, 8... Heater.

Claims (1)

[Scope of Claims] 1. A method for mirror-finishing by electron beam irradiation, characterized by including the following steps. (a) A continuous sheet-like base material and a continuous sheet-like mirror material having a mirror-like surface are laminated with the mirror-like surface facing the base material through a preheated liquid substance having electron beam curability. (b) a step of curing the liquid material by irradiating the laminate with an electron beam; and (c) a step of continuously peeling off the cured material from the continuous sheet-like mirror material. 2. The mirror surface molding method according to claim 1, wherein the liquid material is applied to one surface of the base material in advance before heating. 3. The mirror surface forming method according to claim 1, wherein the liquid substance is applied in advance to the mirror-like surface of the mirror material before heating. 4. The mirror surface molding method according to claim 1, 2, or 3, which includes a step of peeling the cured product from the base material after the step (c). 5 Claims 1, 2, and 3 in which the mirror material or base material has a softening point of 200°C or less
The mirror surface forming method according to item 1 or 4. 6. Claim 1, which includes a heating step at least once after the step (a) or after the step (b).
The method for forming a mirror surface according to item 2, item 3, item 4, or item 5.