JPS60254174A - Duplicating method of hologram - Google Patents

Abstract

PURPOSE:To duplicate a hologram without any deterioration of an original plate by pressing the ultraviolet-ray irradiation setting resin, etc., of a film for hologram formation thermally in contact with the hologram original plate and then irradiating the original plate with ultraviolet rays. CONSTITUTION:The film 1 for hologram formation which has an ultraviolet-ray curing resin with heat moldability or electron-beam curing resin 3 on a base film 2 and the hologram original plate 4 which has interference fringes corresponding to wavefronts of light from a body on the surface as an uneven pattern are pressed against each other on heat condition to form projections and recessed of said resin, and the film 1 for hologram formation is irradiated immediately with electron rays from an irradiation light source 6 to cure the resin 3. Then, the hologram original plate 4 and the film 1 for hologram formation having the projection recess pattern on the surface are spearared from each other to obtain a duplicated hologram.

Description

TECHNICAL FIELD OF THE INVENTION The present invention relates to a method for replicating holograms, and more particularly to a method for replicating holograms that can significantly simplify the replication process and thus enable mass production.

Holography is a new technology that records the wavefront of light from an object, and holograms made using this technology can reproduce three-dimensional images and also allow multiple recording. In addition, as a method for recording holograms, interference fringes corresponding to the wavefront of light from an object can be recorded as an uneven pattern on the surface of a material, and this hologram can be easily reproduced in large quantities.

A hologram like this can be placed on a credit card, for example.
When provided in cards such as bank cards, it is possible to obtain cards that have beauty and novelty, and are difficult to counterfeit or alter. Moreover, if it is provided on the cover of a book, record jacket, clothing, etc., a product with beauty and novelty can be obtained.

In order to place a hologram on cards, book covers, record jackets, etc., it is necessary to start with an object.

Conventionally, holograms have been reproduced by pressing a thermoplastic resin and a hologram master plate, on which interference fringes corresponding to the wavefront of light from an object are formed in an uneven pattern, under heated conditions. This was done by forming unevenness on the surface. However, according to this method, it was necessary to cool the thermoplastic resin and the hologram master while bringing them into pressure contact. This is because if a thermoplastic resin and a hologram master are pressed together under heating conditions to form unevenness on the surface of the thermoplastic resin, and then the pressure is completely released immediately, the unevenness that was once formed on the thermoplastic resin surface will disappear. It is from. Therefore, the hologram copying process requires a long time, and the hologram original plate deteriorates because heating and cooling are repeated many times. Furthermore, since holograms are made of thermoplastic resin, they lack heat resistance and generally have poor solvent resistance.

On the other hand, in order to solve the problems associated with heating, heat resistance, and solvent resistance during hologram duplication, a hologram forming film in which an ultraviolet curing resin is provided on a base film and a hologram original plate have been developed. Attempts have also been made to reproduce holograms by applying pressure and then irradiating ultraviolet light onto the film to cure the resin. However, since the types of UV curable resins that have been used in the past are generally in a liquid state, they become extremely sticky when applied to the base film, and therefore it is difficult to apply conventional UV curable resins onto the base film. The hologram-forming film made by this process cannot be rolled up and stored, so it is necessary to create a hologram-forming film by applying an ultraviolet curing resin onto the base film immediately before it comes into contact with the hologram master. There was a problem.

OBJECTS OF THE INVENTION The present invention is intended to solve the problems associated with these conventional techniques, and has the following objects.

(,) To provide a hologram duplication method that does not require repeated heating and cooling of a hologram original plate and a hologram forming fill plate and does not cause deterioration of the hologram original plate.

(b) Immediately after forming interference fringes corresponding to the wavefront of light from an object in the form of irregularities on the surface of the hologram forming film by keeping the hologram master and the hologram forming film in a heated state and pressing them together, the hologram master plate and the hologram forming film are pressed together. To provide a method for duplicating a hologram by which the state can be released and cooled, thereby clearly simplifying the process of duplicating the hologram, and enabling mass production.

(C) To provide a hologram duplication method that can simplify the hologram duplication process and enable mass production by using a hologram forming film that can be rolled up and stored.

(d) To provide a hologram with excellent heat resistance and solvent resistance.

Summary of the Invention A hologram duplication method according to the present invention comprises a hologram forming film comprising a base film and a thermoformable ultraviolet curable resin or an electron beam curable resin, and a hologram forming film formed by applying a wavefront of light from an object to the surface of the hologram forming film. A hologram original plate having corresponding interference fringes formed as an uneven pattern is brought into pressure contact with the resin under heating conditions to form unevenness in the resin, and then immediately the hologram forming film is irradiated with ultraviolet rays or electron beams. It is a feature.

The present invention will be described below with reference to specific examples shown in the drawings.

The figure shows a hologram replication process according to the present invention. The hologram forming film 1 is a base film 2
A thermoformable ultraviolet curable resin or electron beam curable resin 3 is provided thereon. as needed,
A release layer (not shown) may be provided between the base film 2 and the resin 3.

As the base film 2, any film-like material can be used. Specifically, polyethylene, polypropylene, polyethylene terephthalate, polyvinyl chloride,
Vinyl chloride/vinyl acetate copolymer, polyvinylidene chloride, polymethyl methacrylate, polystyrene, ? Polymer films such as ribinyl petyral and polycarbonate,
Paper, synthetic paper, and metal films such as iron are used for vines.

Moreover, a single product of these can also be used.

Thermoforming that can be used in the present invention; the raw ultraviolet curable resin or electron beam curable resin 3 is solid at room temperature, and when provided on the base film 2, the surface does not become sticky and can be rolled. It is possible to take. Therefore, since the hologram forming film 1 in which the resin is provided on the base film 2 can be rolled up and stored, it is necessary to provide the resin on the base film one by one immediately before contacting the hologram master. There is no.

Materials that can be used for the hologram layer of the present invention are thermoformable substances having a creeping/curing polymerizable unsaturated foundation, and there are two types of materials as follows.

(1) A polymer having a glass transition temperature of 0 to 250°C and having a u-/dical-polymerizable unsaturated group. More specifically, as a polymer, the following compounds ■ to ■ are polymerized or copolymerized using the method (a) to) described below.
It is possible to use those into which radically polymerizable unsaturated groups have been introduced.

■ Monomers having hydroxyl groups 2N-methylolacrylamide, 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl acrylate, 2-hydroxypropyl methacrylate,
2-hydroxybutyl acrylate, 2-hydroxyethyl acrylate, 2-hydroxy, 3-phenoxyzorobyl methacrylate, 2-hydroxy, 3-phenoxypropyl acrylate 7, etc.

■ Monomers with carboxyl groups such as nialic acid, methacrylic acid, acryloyloxyethyl monosuccinate, etc.

■ Monomers such as nigericidyl methacrylate having epoxy groups.

(2) Monomers having an aziridinyl group = 2-aziridinylethyl methacrylate, allyl 2-aziridinylzolopionate, etc.

■ Monomers having amine groups such as niacrylamide, methacrylamide, diaseptone acrylamide, dimethylaminoethyl methacrylate, diethylaminoethyl methacrylate, etc.

■ Monomer containing sulfone group = 2-acrylamide 2-methylpropanesulfonic acid, etc.

(2) Monomers having an incyanate group: adducts of diisocyanates and radially polymerizable monomers having active hydrogen, such as 2,4-toluene, 1 mol to 1 mol adducts of diisocyanate and 2-hydroxyethyl acrylate, and the like.

■Furthermore, in order to adjust the glass transition point of the above copolymer and the physical properties of the cured film, the above compound can be copolymerized with the following monomers that can be copolymerized with this compound. It can also be polymerized.

Examples of such copolymerizable monomers include methyl methacrylate, methyl acrylate, ethyl acrylate, ethyl methacrylate, propyl acrylate, propyl methacrylate, butyl acrylate, butyl methacrylate, inbutyl acrylate, isobutyl methacrylate, t-butyl acrylate, Examples include t-butyl methacrylate, inamyl acrylate, inamyl methacrylate, fluorohexyl acrylate, cyclohexyl methacrylate, 2-ethylhexyl acrylate, 2-ethylhexyl methacrylate, and the like.

Next, the polymer obtained as described above is reacted with the method (a) to (a) to (b) described below to introduce a radically polymerizable unsaturated group.
Monomers having carboxyl groups such as methacrylic acid are subjected to a combination reaction.

Monomers undergo a condensation reaction.

The above-mentioned hydroxyl group-containing monomer or carboxyl group-containing monomer is subjected to an addition reaction.

A 1:1 mole adduct of a monomer having an aziridinyl group or a diisocyanate compound and a hydroxyl group-containing acrylic acid ester monomer is subjected to an addition reaction.

In order to carry out the above reaction, it is preferable to add a small amount of a polymerization inhibitor such as hydroquinone and carry out the reaction while blowing dry air.

(2) A compound having a dicarpolymerizable unsaturated group with a melting point of 0 to 250°C. Specifically, stearyl acrylate, stearyl methacrylate, triacryl iso 7
annulate, cyclohexanediol diacrylate,
Examples include cyclohexanediol dimethacrylate, spiroglycol diacrylate, and spiroglycol dimethacrylate.

Furthermore, in the present invention, the above (1) and (z) can be used as a mixture, and a radically polymerizable unsaturated monomer can also be added to them.

This radically polymerizable unsaturated monomer improves crosslinking density and heat resistance when irradiated with ionizing radiation, and in addition to the above-mentioned monomers, ethylene glycol diacrylate, ethylene glycol dimethacrylate, Polyethylene glycol diacrylate, polyethylene glycol diacrylate, hexanediol diacrylate,
hexanediol dimethacrylate, trimethylolzolobandriacrylate, trimethylolpronocentrimethacrylate, trimethylolpronozone diacrylate, trimethylolpronocentrimethacrylate,
Pentaerythritol tetraacrylate, pentaerythritol tetraacrylate, pentaerythritol triacrylate, pentaerythritol trimethacrylate, dipentaerythritol hexaacrylate,
Dipentaerythritol hexamethacrylate, ethylene glycol diglycidyl ether diacrylate, ethylene glycol dimethacrylate, polyethylene glycol diglycidyl ether diacrylate, polyethylene glycol, propylene glycol diglycidyl ether dimethacrylate, polypropylene glycol digly Zyl ether diacrylate, polyzolopyrene glycol diglydyl ether dimethacrylate, sorbitol tetraglycidyl ether tetraacrylate, sorbitol tetraglycidyl ether tetramethacrylate, etc. can be used,
It is preferably used in an amount of 0.1 to 100 parts by weight based on 100 parts by weight of the solid content of the copolymer mixture described above. In addition, although the above-mentioned materials can be sufficiently cured by electron beams,
When curing by ultraviolet irradiation, sensitizers that generate radicals by ultraviolet irradiation, such as benzoin ethers such as 4-zoquinone, benzoin, and benzoin methyl ether, halogenated acetophenones, and biacyl, can also be used. .

The hologram original plate 4 has irregularities formed on its surface, which are interference fringes corresponding to the wavefront of light from an object. This hologram master plate 4 can be created by a conventionally known method, and the hologram formed on the hologram master plate 4 is of a type in which hologram information can be recorded by the unevenness of the material surface. Excluding holograms, the principles include Fresnel holograms, Fourier transform holograms, and Crownhofer holograms, as well as image holograms, rainbow holograms, holographic stereo durams, etc. that utilize these principles.
A holographic diffraction grating or the like is used.

The hologram forming film 1 and the ultraviolet curing resin or electron beam curing resin 3 of the hologram forming film 1 as described above.
The entire uneven pattern of the hologram original plate 4 is replicated on the surface of the hologram original plate 4.

At this time, the temperature of the heating roll varies greatly depending on the 30 types of resins used, but it is preferably from 300°C to 300°C, preferably from 100 to 200°C. Furthermore, the hologram forming film 1 and the hologram original plate 4 are
It is preferable that the welding is carried out under a pressure of 0.1 kg/em or more, preferably 1 kg/cm or more.

Interference fringes corresponding to the wavefront of light from the body are formed on a hologram as a fully uneven pattern, and the hologram is carved using ultraviolet rays if it is an ultraviolet curable resin or an electron beam if it is an electron beam curable resin while in pressure contact with the hologram original. The resin 3 is cured by irradiating it onto the film l.

The irradiation of ultraviolet rays or electron beams onto the hologram forming film may be performed using the irradiation light source 6.

At this time, the irradiation with ultraviolet rays or electron beams may be carried out again after the film formed with the hologram irregularities of the hologram original plate is peeled from the plate, and it is preferable that the resin is sufficiently cured. It is necessary to adjust the amount of ultraviolet ray or electron beam irradiation appropriately depending on the resin used.

By thus forming irregularities on the surface of the ultraviolet curable resin or electron beam curable resin of the hologram forming film 1, the resin is cured by irradiating ultraviolet rays or electron beams. It becomes possible to completely release the pressure applied between the film and the film and cool it. This is because the resin is immediately cured by irradiation with off-line radiation or electron beam, and therefore, the formed irregularities do not disappear even if the pressure applied between the hologram original plate and the hologram forming film is released. Furthermore, since the resin is three-dimensionally crosslinked and cured by irradiation with ultraviolet rays or electron beams, heat resistance and solvent resistance are imparted.

Although the hologram master and the hologram forming film may be forcibly cooled before or after irradiation with ultraviolet rays or electron beams, it is usually sufficient to cool them naturally.

Next, a duplicate hologram is obtained by peeling off the hologram original plate and the hologram-forming film having the uneven pattern formed on its surface. Further, if necessary, by further irradiating the resin with ultraviolet rays or electron beams after peeling, the resin can be sufficiently cured, and the hardness, heat resistance, solvent resistance, etc. can be improved.

In addition, in the same way as when using the conventional thermal 0T plastic resin using the hologram molding film of the present invention, the hologram original plate and the hologram molding film are cooled after being heated and pressed to form irregularities. Of course, even if you use the peeling method, you can obtain a duplicate hologram, and if you further irradiate it with ultraviolet rays or electron beams,
It can provide heat resistance and solvent resistance to holograms.

Effects of the Invention The method for duplicating a hologram according to the present invention comprises: a hologram-forming film comprising a thermoformable ultraviolet curable resin or an electron beam curable resin provided on a base film;
A hologram original plate having irregularities corresponding to the wavefront of light from an object is formed on the surface, and the resin is pressed under heating conditions to form irregularities, and then ultraviolet rays or electron beams are used to form the hologram. Since this is done by irradiating the film, the following effects can be obtained.

(&) There is no need to press the hologram master and the hologram forming film into a heated state for a long time, and therefore the unevenness of the hologram master does not disappear due to heat.

(b) After the hologram forming film and the hologram master are kept in a heated state and pressed together to form irregularities on the film, the pressed state can be immediately released, and therefore the cooling process can be carried out in a short time. This greatly simplifies the hologram duplication process and enables mass production.

(c) The hologram forming film can be rolled up and stored, thus simplifying the hologram duplication process and making mass production possible.

(d) To provide a hologram with excellent heat resistance and solvent resistance.

EXAMPLES The present invention will be explained below with reference to Examples, but the present invention is not limited to these Examples.

Example 1 The following composition was refluxed for 6 hours to perform copolymerization.

Methyl methacrylate 300 parts 2-hydroxyethyl methacrylate 130 parts Ethyl acetate 1000 parts αGe azobisisobutyronitrile 2 parts then 0.1
After adding iR silatoxyphenol from Shizutsube to stop the reaction, 100 parts by weight of a 1 mole to 1 mole adduct of 2-hydroxyethyl acrylate and 2.4-toluene diisocyanate was added to the resulting reaction product, Furthermore, 5 parts of dibutyltin silaurylate were added, and the mixture was reacted at 80° C. for 5 hours while blowing dry air.

After cooling the reaction solution to room temperature, 15 parts by weight of an ultraviolet sensitizer (Irgateur 184 manufactured by Ciba Geigy) was added.
A resin liquid for a hologram layer was obtained by uniformly dissolving the resin. Next, this resin liquid was applied to polyethylene terephthalate film δ.
The solution was coated on a μm (Lumirror manufactured by Toshi) so that the solid content was 3 g/m, and the solvent was dried to obtain a hologram-forming film. Next, the resin coated surface of this hologram forming film is superimposed on the uneven surface of a mold in which a hologram is recorded in an uneven shape as a hologram master, 1
Pass through 20 kg/cm nip rolls at 60℃,
In this state, the hologram forming film was peeled off from the hologram master plate after curing the resin by irradiating it with ultraviolet rays at a speed of 10 m 7 ml 'n at a position 10 cm below the film surface under an 80 W/am mercury lamp. An uneven shape was formed on the resin surface, and a hologram could be replicated. This replicated hologram also had excellent heat resistance and solvent resistance.

Example 2 The following composition was refluxed for 6 hours to perform copolymerization.

Methyl methacrylate 320 parts by weight Butyl methacrylate 130 parts by weight Glycidyl methacrylate 284 parts by weight Toluene 1
290 parts by weight Methyl ethyl ketone 1290 parts by weight α,α'-azobisisobutyronitrile 25 parts by weight Next, 0.2 parts by weight of hydroquinone was added to the obtained reaction product to stop the reaction, and 158 parts by weight of acrylic acid, Add 10 parts by weight of pyridine and add 9 parts by weight while blowing dry air.
The reaction was carried out at 0° to 100°C for 8 hours.

The obtained material was dried into a polyethylene terephthalate film with a thickness of 5 μm. ．． It was applied uniformly to a concentration of 5 g/m2, and the solvent was dried to obtain a hologram forming film. The obtained film does not stick at room temperature and can be stored in a rolled state.

Next, the resin surface of this coated film and the uneven surface of a mold, which is a hologram original plate in which a hologram is recorded in an uneven shape, are overlapped and heated and pressed from above and below in the same manner as in Example 1. The coated film was brought into close contact with the film. Furthermore, in this state, an electron beam accelerated to 175KV is applied from the film side to 5M.
When the coated resin was cross-linked and cured by rad irradiation and the mold and coated film were separated, a hologram in which the uneven shape of the mold was formed was replicated on the resin surface of the coated film.

This replicated hologram had excellent heat resistance and solvent resistance.

[Brief explanation of the drawing]

The figure is a cross-sectional view showing the manufacturing process of the hologram duplication method according to the present invention. 1... Hologram forming film 2... Base film 3... Ultraviolet curing resin or electron beam curing resin 4...
Hologram original plate 5...Heating pressure welding roll 6...Irradiation light source

Claims (1)

[Claims] A hologram forming film consisting of a thermoformable ultraviolet curable resin or electron beam curable resin on a base film, and a hologram with uneven interference fringes corresponding to the wavefront of light from an object on the surface. The hologram original plate is pressed against the hologram original plate under heating conditions so that the ultraviolet ray curing resin or electron beam curing resin of the film is in contact with the hologram original plate to form irregularities on the resin, and then ultraviolet rays or electron beams are applied for hologram formation. A hologram reproduction method characterized by irradiating a film.