JPH11291380A - Volumetric hologram laminate and label for manufacturing volumetric hologram laminate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a volumetric hologram laminate which is almost free from a mottle defect to be generated in a volumetric hologram lever even under such a state that the laminate is conserved under an applied pressure as when it is stored or the like as well as a label for manufacturing the volumetric hologram laminate. SOLUTION: This volumetric hologram laminate 1 is formed of a first pressure-sensitive adhesive layer 3, a volumetric hologram layer 5, a second pressure-sensitive adhesive layer 4 and a surface protecting film 6 laminated sequentially on a base material 2. The volumetric hologram layer 5 is recorded in a recording material made up of a matrix polymer and a photopolymerizale compound by hologram process. And the layer 5 has 30-70 deg.C glass transition point and 5×10<5> Pa-5×10<7> Pa dynamic storage modulus at 50 deg.C when measured at 6.28 rad/s. In addition, the second pressure-sensitive adhesive layer 4 shows less than 1 or 2 or more maximum value of the logarithmic decrement when the surface viscoelastic properties are measured in a pendulum type rigid physical properties test.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a volume hologram laminate and a label for producing a volume hologram laminate which can reduce patchy hologram defects generated during transportation or storage under pressure in a warehouse or the like.

[0002]

2. Description of the Related Art Conventionally, a volume hologram laminate generally comprises an adhesive layer, a volume hologram layer, an adhesive layer,
Transparent protective films are stacked in this order, and as a base material, a variety of forms such as identification cards, examination cards, ID cards, and booklets such as passports have been developed. A recording material composed of a matrix polymer and a photopolymerizable compound as a recording material is used as a dry volume phase hologram recording material. When stored in a state where the hologram is stored, a problem is that mottled hologram defects occur.

[0003] The spot-like hologram defects are found when the hologram recording layer is observed, and the spot size is an elliptical shape having a major axis of about 0.2 to 2 mm and a minor axis of about 0.1 to 1.5 mm. Or a circular shape having a radius of about 0.1 to 2 mm, which is regularly arranged. Since the hologram defect depends on the light source and the viewing angle, it is considered that the hologram defect is not caused by the inclusion of bubbles or foreign matter in the volume hologram layer but is a holographic defect.

[0004]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a volume hologram laminate having no such hologram defects and a label for producing the volume hologram laminate. It is another object of the present invention to provide a volume hologram laminate and a label for producing a volume hologram laminate, in which patchy hologram defects are less likely to occur in the volume hologram layer.

[0005]

A volume hologram laminate according to the present invention is a volume hologram laminate in which a first pressure-sensitive adhesive layer, a volume hologram layer, a second pressure-sensitive adhesive layer, and a surface protection film are sequentially laminated on a substrate. In the body, the volume hologram layer is hologram-recorded on a recording material comprising a matrix polymer and a photopolymerizable compound, and has a glass transition point of 30 ° C to 70 ° C and 6.28 rad /.
The dynamic storage modulus at 50 ° C. in the s measurement is 5 × 10 ⁵
Pa to 5 × 10 ⁷ Pa, and the second pressure-sensitive adhesive layer has a maximum logarithmic decrement of less than 1 or 2 or more in a surface viscoelasticity measurement in a pendulum-type rigidity property test. Features.

In the label for producing a volume hologram laminate of the present invention, a first pressure-sensitive adhesive layer, a volume hologram layer, a second pressure-sensitive adhesive layer, and a surface protection film are sequentially laminated on a release sheet,
The volume hologram layer is a hologram recorded on a recording material composed of a matrix polymer and a photopolymerizable compound, and has a glass transition point of 30 ° C to 70 ° C and 50 ° C in 6.28 rad / s measurement. The dynamic storage modulus is 5 × 10 ⁵ Pa to ⁵ × 10 ⁷ Pa, and the second pressure-sensitive adhesive layer has a maximum logarithmic decrement in the surface viscoelasticity measurement in a pendulum-type rigidity property test. It is characterized by being less than one or two or more.

Further, the half width of the diffracted light of the volume hologram recorded on the volume hologram layer in the volume hologram laminate and the label for producing the volume hologram laminate is 3
It is characterized by being less than 0 nm.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION In the present invention, a hologram defect in a volume hologram laminate is caused by a correlation between the hardness of the volume hologram layer and the hardness of an adhesive layer provided between the volume hologram layer and the surface protection film. The present inventors have found out that there is, and have completed the present invention.

FIG. 1 is a sectional view of the volume hologram laminate of the present invention. In the figure, 1 is a volume hologram laminate, 2 is a substrate, 3 is a first adhesive layer, 4 is a second adhesive layer, 5 is a volume hologram layer, and 6 is a surface protection film.

As the substrate 2 in the volume hologram laminate of the present invention, a film or a sheet made of paper, synthetic paper, synthetic resin or metal can be used.
In addition, it can take various forms such as a card shape such as an ID card and a booklet such as a passport, and is used as a base material on which a volume hologram body in which a photographic hologram of a face photograph, scenery, etc. is recorded in a single color or full color is attached. You. When a color filter of a liquid crystal display element is used, a glass substrate or an electrode layer in a liquid crystal cell is a base material.

Further, the volume hologram laminate of the present invention comprises:
FIG. 1 illustrates a configuration in which a volume hologram layer 5 is laminated on a base material 2 via a first adhesive layer 3.
The volume hologram layer 5 may be laminated on the substrate 2 with a double-sided pressure-sensitive adhesive tape interposed therebetween. In this case, the second hologram layer 5 is formed on the base material 2 with a pressure-sensitive adhesive layer or a plastic film such as a transparent or colored polyethylene terephthalate film. The first adhesive layer 3, the volume hologram layer 5, the second adhesive layer 4, and the surface protection film 6 may be sequentially laminated.

In the volume hologram layer 5, after a volume hologram recording material is applied on a support film, interference fringes corresponding to the wavefront of light from an object are recorded in the layer in the form of transmittance modulation and refractive index modulation. It can be easily produced by copying and exposing the volume hologram master to exposure and development.

The volume hologram layer 5 includes a matrix polymer, a photopolymerizable compound, a photopolymerization initiator, a sensitizing dye,
And a dry-type photosensitive material for volume phase hologram recording comprising a plasticizer added as required.

Examples of the photopolymerizable compound include photopolymerizable and photocrosslinkable monomers and oligomers having at least one ethylenically unsaturated bond in one molecule as described below.
Prepolymers, and mixtures thereof, for example, unsaturated carboxylic acids, and salts thereof, esters of unsaturated carboxylic acids and aliphatic polyhydric alcohol compounds, and unsaturated carboxylic acids and aliphatic polyhydric amine compounds. Amide bonds may be mentioned.

Specific examples of unsaturated carboxylic acid monomers include acrylic acid, methacrylic acid, itaconic acid, crotonic acid, isocrotonic acid, maleic acid, and halogen-substituted unsaturated carboxylic acids such as chlorinated unsaturated carboxylic acids. , Brominated unsaturated carboxylic acids, fluorinated unsaturated carboxylic acids, and the like. The salts of unsaturated carboxylic acids include the sodium and potassium salts of the aforementioned acids.

Further, specific examples of the monomer of the ester of the aliphatic polyhydric alcohol compound and the unsaturated carboxylic acid include acrylates such as ethylene glycol diacrylate, triethylene glycol diacrylate, and 1,3-butanediol diacrylate. Acrylate, tetramethylene glycol diacrylate, propylene glycol diacrylate, neopentyl glycol diacrylate, trimethylolpropane triacrylate, trimethylolpropane tri (acryloyloxypropyl) ether, trimethylolethane triacrylate, hexanediol diacrylate, 1,4 -Cyclohexanediol diacrylate, tetraethylene glycol diacrylate, pentaerythritol diacrylate, pentaerythritol Triacrylate, pentaerythritol tetraacrylate, dipentaerythritol diacrylate, dipentaerythritol triacrylate, dipentaerythritol tetraacrylate, dipentaerythritol hexaacrylate, sorbitol triacrylate, sorbitol tetraacrylate, sorbitol pentaacrylate, sorbitol hexaacrylate, tri ( (Acryloyloxyethyl) isocyanurate, polyester acrylate oligomer, 2-phenoxyethyl acrylate, 2-phenoxyethyl methacrylate, phenol ethoxylate monoacrylate, 2- (p-chlorophenoxy)
Ethyl acrylate, p-chlorophenyl acrylate, phenyl acrylate, 2-phenylethyl acrylate, (2-acryloxyethyl) ether of bisphenol A, ethoxylated bisphenol A diacrylate, 2- (1-naphthyloxy) ethyl acrylate, o -Biphenyl methacrylate, o-biphenyl acrylate and the like.

Examples of methacrylic acid esters include tetramethylene glycol dimethacrylate, triethylene glycol dimethacrylate, neopentyl glycol dimethacrylate, trimethylolpropane trimethacrylate, trimethylolethane trimethacrylate, ethylene glycol dimethacrylate, and 1,3-butanediol. Dimethacrylate, hexanediol dimethacrylate, pentaerythritol dimethacrylate, pentaerythritol trimethacrylate, pentaerythritol tetramethacrylate, dipentaerythritol dimethacrylate, dipentaerythritol hexamethacrylate, sorbitol trimethacrylate, sorbitol tetramethacrylate, bis- [p- (3 -Methacryloxy-2- Mud propoxy) phenyl] dimethyl methane, bis - [p- (acryloxy ethoxy phenyl] dimethyl methane, 2,2-bis (4-methacryloyloxy) propane, methacrylate -2
-Naphthyl and the like.

Examples of itaconic esters include ethylene glycol diitaconate, propylene glycol diitaconate, 1,3-butanediol diitaconate,
4-butanediol diitaconate, tetramethylene glycol diitaconate, pentaerythritol diitaconate, sorbitol tetritaconate, and the like.

The crotonates include ethylene glycol dicrotonate, tetramethylene glycol dicrotonate, pentaerythritol dicrotonate,
And sorbitol tetracrotonate.

Examples of the isocrotonic acid ester include ethylene glycol diisocrotonate, pentaerythritol diisocrotonate, and sorbitol tetraisocrotonate.

Examples of the maleic acid ester include ethylene glycol dimaleate, triethylene glycol dimaleate, pentaerythritol dimaleate, and sorbitol tetramaleate.

The halogenated unsaturated carboxylic acids include
2,2,3,3-tetrafluoropropyl acrylate, 1H, 1H, 2H, 2H-heptadecafluorodecyl acrylate, 2,2,3,3-tetrafluoropropyl methacrylate, 1H, 1H, 2H, 2H-heptadeca Fluorodecyl methacrylate, methacrylic acid
2,4,6-tribromophenyl, dibromoneopentyl dimethacrylate (trade name: NK ester DBN, manufactured by Shin-Nakamura Chemical Co., Ltd.), dibromopropyl acrylate (trade name: NK ester A-DBP, Shin-Nakamura Chemical Co., Ltd.) Dipromopropyl methacrylate (trade name: NK ester DBP, manufactured by Shin-Nakamura Chemical Co., Ltd.),
Methacrylic acid chloride, methacrylic acid-2,4,6-
Trichlorophenyl, p-chlorostyrene, methyl-2
-Chloroacrylate, ethyl-2-chloroacrylate, n-butyl-2-chloroacrylate, tribromophenol acrylate, tetrabromophenol acrylate and the like.

Specific examples of the amide monomer of an unsaturated carboxylic acid and an aliphatic polyamine compound include methylenebisacrylamide, methylenebismethacrylamide, 1,6-hexamethylenebisacrylamide,
6-Hexamethylenebismethacrylamide, diethylenetriaminetrisacrylamide, xylylenebisacrylamide, xylylenebismethacrylamide, N-phenylmethacrylamide, diacetoneacrylamide and the like.

As another example, see JP-B-48-417.
No. 08-208, a polyisocyanate compound having two or more isocyanate groups in one molecule, represented by the following general formula: CH ₂ CC (R) COOCH ₂ CH (R ′) OH (where R and R ′ are hydrogen or And a vinyl urethane compound containing two or more polymerizable vinyl groups in one molecule to which a hydroxyl-containing vinyl monomer represented by the following formula:

Further, urethane acrylates described in JP-A-51-37193, JP-A-48-641
No. 83, Japanese Patent Publication No. 49-43191, Japanese Patent Publication No. 5
Polyester acrylates, epoxy resins and (meth) as described in JP-A-2-30490, respectively.
Examples include polyfunctional acrylates and methacrylates such as acrylic acid.

Further, the Journal of the Adhesion Society of Japan, Vol. 20, N
o7, those introduced as photocurable monomers and oligomers on pages 300 to 308 can also be used.

Other monomers containing phosphorus include mono (2-acryloyloxyethyl) acid phosphate (trade name: Light Ester PA, manufactured by Kyoeisha Yushi Kagaku Kogyo KK) and mono (2-methacryloyl ethyl) Acid Phosphate (trade name: Light Ester PM, manufactured by Kyoeisha Yushi Kagaku Kogyo Co., Ltd.); epoxy acrylate-based trade name: Lipoxy VR-60 (manufactured by Showa Polymer Co., Ltd.); trade name: Lipoxy VR-90 (manufactured by Showa Polymer Co., Ltd.) and the like.

Trade name: NK ester M-230G
(Manufactured by Shin-Nakamura Chemical Co., Ltd.), trade name: NK Ester 2
3G (manufactured by Shin-Nakamura Chemical Co., Ltd.) is also included.

Further, triacrylates having the following structural formula:

[0030]

Embedded image

(Trade name, Aronix M-315, manufactured by Toa Gosei Chemical Industry Co., Ltd.)

[0032]

Embedded image

(Trade name, Aronix M-325, manufactured by Toa Gosei Chemical Industry Co., Ltd.) and 2,2'-bis (4-
Acryloxy diethoxyphenyl) propane (manufactured by Shin-Nakamura Chemical Co., Ltd., trade name, NK ester A-BPE-4), tetramethylolmethanetetraacrylate (Shin-Nakamura Chemical)
(Trade name, NK Ester A-TMMT), and the like.

Examples of the plasticizer added as needed include polyhydric alcohols such as ethylene glycol, diethylene glycol, triethylene glycol, glycerin and trimethylolpropane, and dimethyl phthalate (DM).
P), diethyl phthalate (DEP), dibutyl phthalate (DBP), heptyl nonyl phthalate (HNP), di-2-ethylhexyl phthalate (DOP), di-phthalate
n-octyl (DNOP), di-i-octyl phthalate (DCapP), (79 alkyl) phthalate (D79
P), di-i-decyl phthalate (DIDP), ditridecyl phthalate (DTDP), dicyclohexyl phthalate (DCHP), butyl benzyl phthalate (BDP), ethyl phthalyl ethyl glycolate (EPEG), butyl phthalyl butyl Phthalate plasticizers such as glycolate (BPBG), di-2-ethylhexyl adipate (DOA), di- (methylcyclohexyl) adipate, diisodecyl adipate (DIDA), azelaic acid-di-n- Hexyl (DNMH), azelaic acid-
Di-2-ethylhexyl (DOZ), dibutyl sebacate (DBS), di-2-ethylhexyl sebacate (D
OS) or other aliphatic dibasic acid ester plasticizers, triethyl citrate (TEC), tributyl citrate (TB
C), citrate plasticizers such as acetyl triethyl citrate (ATEC) and tributyl acetyl citrate (ATBC), epoxy plasticizers such as epoxidized soybean oil, tributyl phosphate (TBP), triphenyl phosphate ( TPP), tricresyl phosphate (YCP), and tripropylene glycol phosphate, and the like.

Next, as a photopolymerization initiator in the initiator system, 1,3-di (t-butyldioxycarbonyl) benzophenone, 3,3 ', 4,4'-tetrakis (t-
(Butyldioxycarbonyl) benzophenone, N-phenylglycine, 2,4,6-tris (trichloromethyl) -s-triazine, 3-phenyl-5-isoxazolone, 2-mercaptobenzimidazole, and imidazole dimers Etc. are exemplified. The photopolymerization initiator is
From the viewpoint of stabilization of the recorded hologram, it is preferable that the hologram is decomposed after recording the hologram. For example, organic peroxides are preferable because they are easily decomposed by ultraviolet irradiation.

The sensitizing dyes include thiopyrylium salt dyes, merocyanine dyes, quinoline dyes, styrylquinoline dyes, ketocoumarin dyes, thioxanthene dyes, xanthene dyes, and oxonol dyes having absorption light at 350 to 600 nm. Dyes, cyanine dyes, rhodamine dyes, thiopyrylium salt dyes, pyrylium ion dyes, and diphenyliodonium ion dyes are exemplified. Note that a sensitizing dye having absorption light in a wavelength region of 350 nm or less or 600 nm or more may be used.

Examples of the matrix polymer include polymethacrylic acid ester or its partial hydrolyzate, polyvinyl acetate or its hydrolyzate, polyvinyl alcohol or its partial acetalized product, triacetyl cellulose, polyisoprene, polybutadiene, polychloroprene, Silicone rubber, polystyrene, polyvinyl butyral, polychloroprene, polyvinyl chloride, chlorinated polyethylene, chlorinated polypropylene, poly-N-vinyl carbazole or its derivatives, poly-N-vinyl pyrrolidone or its derivatives, styrene and maleic anhydride Polymer or its half ester, acrylic acid, acrylic acid ester, methacrylic acid, methacrylic acid ester, acrylamide, acrylonitrile, ethylene, propylene, vinyl chloride, vinyl acetate Copolymers or mixtures thereof, are used to at least one polymerizable component copolymerizable monomers set forth. Preferably polyisoprene,
Polybutadiene, polychloroprene, polyvinyl alcohol, and polyvinyl acetal which is a partially acetalized product of polyvinyl alcohol, polyvinyl butyral,
Examples include polyvinyl acetate, ethylene-vinyl acetate copolymer, vinyl chloride-vinyl acetate copolymer, and the like, and mixtures thereof.

As a step of stabilizing the recorded hologram, there is a step of monomer transfer by heating. For this purpose, these matrix polymers preferably have a relatively low glass transition temperature and facilitate monomer transfer. It is necessary to be.

The photopolymerizable compound is a binder resin 1
It is used in an amount of 10 parts by weight to 1000 parts by weight, preferably 10 parts by weight to 100 parts by weight based on 00 parts by weight.

The photopolymerization initiator is used in an amount of 1 to 10 parts by weight, preferably 5 to 10 parts by weight, based on 100 parts by weight of the binder resin.

The sensitizing dye is used in an amount of 0.01 to 1 part by weight, preferably 0.0 to 1 part by weight, based on 100 parts by weight of the binder resin.
It is used in a proportion of 1 part by weight to 0.5 part by weight.

Other examples of the photosensitive material component include various nonionic surfactants, cationic surfactants, and anionic surfactants.

These hologram recording materials include acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, benzene, toluene, xylene, chlorobenzene, tetrahydrofuran, methyl cellosolve,
Ethyl cellosolve, methyl cellosolve acetate, ethyl cellosolve acetate, ethyl acetate, 1,4-dioxane, 1,2-dichloroethane, dichloromethane, chloroform, methanol, ethanol, isopropanol or the like, or a mixed solvent thereof, is used. % ~
It is a 25% coating liquid. The thickness of the hologram recording layer is 0.1 μm to 50 μm, preferably 5 μm to 20 μm.
μm.

As such a hologram recording material, for example, Omnidex 352, 70 manufactured by Tupon Corporation
6 are mentioned.

In the volume hologram layer of the present invention, the recording light is, for example, 337.5 nm, 350.7 n in a krypton laser (1.5 W).
m, 356.4 nm wavelength light, and 351.1 nm, 368.8 nm in an argon laser (40 mW).
Wavelength light and 3 in a neon laser (50 mW)
32.4nm wavelength light, cadmium laser (15m
W) at 325.0 nm wavelength, and 514.5 nm, 44.5 nm,
88 nm, 457.9 nm wavelength light, and 647.1 nm, 568.2 nm, 5
A monochromatic hologram or a color hologram is exemplified by a light having a wavelength of 20.8 nm, of which one wavelength is taken out, and a hologram is recorded by exposing to a wavelength capable of exciting the photopolymerization initiator.

In the present invention, the volume hologram layer (hereinafter, referred to as the hologram layer)
When a volume hologram layer is defined by various physical properties, it means a volume hologram layer in a state where a hologram is recorded.)
Has a glass transition point of 30 ° C. to 70 ° C., preferably 35 ° C.
〜60 ° C.

The dynamic storage modulus of the volume hologram layer in the present invention is one of the physical properties reflecting the hardness of the volume hologram layer, and employs the following measuring apparatus and measuring method.

Sample for measurement: Hologram recording film: P
Hologram recording on laminated film of ET film / volume hologram layer / polyvinyl chloride film or PET film, and then peeling off PET film, polyvinyl chloride film or PET film Volume hologram film Measuring device: Solid viscoelastic analyzer RSA-II Leo Metrics Attachment (mode): Film tension Measurement frequency: Temperature dependence measured at 6.28 rad / s Measurement temperature: −50 ° C. to 100 ° C. Measurement method: A sample is set on a film tension measuring jig. 6.28 rad / in the temperature range of -50 ° C to 100 ° C.
Measure the temperature dependence at s, and from the temperature dependence data,
Dynamic storage modulus at 25 ° C and 50 ° C (E ', Pa)
Ask for. In addition, from the viewpoint of hardness comparison at room temperature, 2
5 ° C. was selected, and 50 ° C. was selected from the viewpoint of comparison of hardness in a storage state in a warehouse or the like in summer. The volume hologram layer in the present invention has a dynamic storage modulus at 50 ° C. of 5 × 10 ⁵ Pa to ⁵ × 10 ⁷ Pa.

The half width of the diffracted light of the volume hologram recorded on the volume hologram layer of the present invention is 30 nm or less. For a volume hologram recorded using a color tuning film and having a half-value width of the diffracted light of the volume hologram exceeding 30 nm, the detailed reason is unknown, but as described later in the reference example, the pressurized state Are unlikely to cause a patchy hologram defect. In the present invention, in particular, the half width of the diffracted light of the volume hologram is 30 nm.
It is effective in the following color Lippmann hologram and monochromatic hologram.

Next, the pressure-sensitive adhesive layers 3 and 4 will be described.
Examples of the pressure-sensitive adhesive layer include an acrylic resin, an acrylate resin, or a copolymer thereof, a styrene-butadiene copolymer, a natural rubber, a casein, a gelatin, a rosin ester, a terpene resin, a phenolic resin, a styrene resin, and a chroman resin. Indene resins, polyvinyl ethers, silicone resins, etc., and alpha-cyanoacrylate, silicone, maleimide, styrene, polyolefin, resorcinol, and polyvinyl ether pressure-sensitive adhesives can also be used. In addition, the pressure-sensitive adhesive layer can be formed using a so-called two-component cross-linking pressure-sensitive adhesive that is cross-linked by adding an isocyanate-based cross-linking agent, a metal chelate-based cross-linking agent, or the like at the time of use. The thickness of the adhesive layer is from 4 μm
The thickness is preferably 20 μm.

The maximum value of the logarithmic decrement in the surface viscoelasticity measurement of the second pressure-sensitive adhesive layer between the volume hologram layer and the surface protective film in the present invention is one of physical properties reflecting the hardness of the pressure-sensitive adhesive layer. It is defined by the surface viscoelasticity measured value in the following pendulum-type rigidity property test.

Hereinafter, the measuring device and the measuring method will be described.

Sample for measurement: An adhesive was applied to a separator A (“SP-PET05” manufactured by Tokyo Cellophane Co., Ltd.) to a dry film thickness of 15 μm, and a separator B was applied to the coated surface.
("SP-PET02" manufactured by Tokyo Cellophane Co., Ltd.) and aged at room temperature for one week. At the time of measurement, this adhesive film is cut into a predetermined size, the separator A is peeled off, the adhesive layer is transferred onto a smooth SUS, and the separator B is peeled off before the measurement.

Measuring device: Rigid pendulum type physical property tester RPT
-Α-100 (manufactured by Tohoku Electronics Co., Ltd.) Measurement temperature: -50
℃ ~ 100 ℃ Measurement section shape: rbp20, frame type: frb-1
0 Rate of inertia: 1230 Measurement method: Set a sample.

Pendulum adjustment: amplitude, period (predetermined value)
To match.

The maximum value of the obtained logarithmic decay rate (Δma
x) is determined.

FIG. 2 shows an example of data obtained for the maximum value (Δmax) of the logarithmic decay rate. In the figure, the triangle indicates the logarithmic decay rate, the square indicates the period, and the maximum value of the logarithmic decay rate (Δma
x) is 0.776, which relates to the second pressure-sensitive adhesive layer produced in Example 3 described later.

The second pressure-sensitive adhesive layer in the third volume hologram laminate of the present invention can also be specified by the maximum value of the logarithmic decrement obtained by measuring the surface viscoelasticity in the pendulum-type rigidity property test. The maximum value of the logarithmic decay rate occurs at the time of glass transition, but the value is less than 1, preferably 1
Less than 0.08, and 2 or more, preferably 2 to 4
When the value is 1 or more and less than 2, the number of patchy hologram defects rapidly increases under a pressurized condition.

Next, the surface protective film 6 in the volume hologram laminate of the present invention has transparency, and is a polyethylene film, a polypropylene film, a polyfluoroethylene film, a polyvinylidene fluoride film, a polyvinyl chloride film, Polyvinylidene chloride film, ethylene-vinyl alcohol film, polyvinyl alcohol film, polymethyl methacrylate film, polyether sulfone film, polyether ether ketone film, polyamide film, tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer film, polyethylene terephthalate film, etc. Resins such as polyester film and polyimide film are exemplified, and the film thickness is 2 μm to 200 μm, preferably 10 μm.
μm to 50 μm.

Although not shown, the surface protective film may be subjected to a hard coat treatment as needed for the purpose of enhancing the protection of the surface protective film surface.
The hard coat treatment is performed, for example, by dipping coating, spray coating, or roll coating using a silicone-based, fluorine-containing silicone-based, melamine alkyd-based, urethane-acrylate-based (ultraviolet curable) coating method, and a film thickness of 1 μm to 5 μm.
The coating may be applied at 0 μm, preferably 3 μm to 25 μm.

Further, similarly, although not shown, the surface of the surface protective film 7 or the surface of the hard coat treatment may be subjected to a release treatment. The release treatment may be performed by dipping, spraying, or roll coating a fluorine-based release agent, a silicone-based release agent, a stearate-based release agent, a wax-based release agent, or the like.

Next, FIG. 3 shows a layer structure of a cross section of a label for producing a volume hologram laminate used in producing the volume hologram laminate of the present invention. In the figure, 10 is a label for producing a volume hologram laminate,
Reference numeral 11 denotes a release paper, and the same reference numerals as those in FIG. 1 indicate the same contents.

The label for producing a volume hologram laminate of the present invention is used for producing the above-mentioned volume hologram laminate, and as shown in FIG. It is obtained by laminating a layer 5, a second pressure-sensitive adhesive layer 4, and a surface protection film 6.

Further, in FIG. 3, the volume hologram laminate label of the present invention has a first pressure-sensitive adhesive layer 3 on release paper 11.
Although the configuration in which the volume hologram layer 5 is laminated through the intermediary is illustrated, a structure in which the volume hologram layer 5 is laminated on the release paper 11 via a double-sided adhesive tape may be used. In this case,
An adhesive layer, a plastic film layer such as a transparent or colored polyethylene terephthalate film, a first adhesive layer 3, a volume hologram layer 5, a second adhesive layer 4, and a surface protection film 6 sequentially laminated on a release paper 11. It may be.

As the release paper 11, a release film obtained by subjecting the surface of a polyethylene terephthalate film to a release treatment with a fluorine-based release agent or a silicone-based release agent may be used in addition to a commonly used release paper. Further, the surface of the release paper which is not on the side of the adhesive layer may be subjected to a release treatment in order to avoid blocking by the adhesive protruding from the side of the label. Further, the laminate may be so-called "semi-punched" so that the laminate can be peeled off from the release paper in an appropriate size, or a cutout such as a perforation may be formed in the release paper. .

After the release paper 11 is peeled off, the label 10
The first pressure-sensitive adhesive layer 3 is laminated on the base material in the volume hologram laminate from the side of the first pressure-sensitive adhesive layer 3 to produce the volume hologram laminate shown in FIG.

[0067]

The present invention will be described below with reference to examples. (Example 1) (Preparation of transparent protective film / second pressure-sensitive adhesive layer / silicon separator) On a silicon separator (Tokyo Cellophane Co., Ltd. “SP-PE05” film thickness 50 μm), the following composition: acrylic pressure-sensitive adhesive ("Nissetsu PE-118" manufactured by Nippon Carbide Co., Ltd.) 100 parts by weight Methyl ethyl ketone 30 parts by weight Toluene 15 parts by weight Ethyl acetate 15 parts by weight Isocyanate crosslinking agent (Japan 16 parts by weight of the pressure-sensitive adhesive solution was immediately applied with a comma coater to a dry film thickness of 15 μm. A polyethylene terephthalate film (Lumirror T-60, manufactured by Toray Industries, Inc.)
(A film thickness of 50 μm) was laminated.

When the surface viscoelasticity of the pressure-sensitive adhesive layer was measured, the maximum value of the logarithmic decrement was 0.442.

(Silicone separator A / first pressure-sensitive adhesive layer /
Production of silicon separator B) Silicon separator A
(Tokyo Cellophane “SP-PET05” film thickness 5
0 μm), immediately apply a pressure-sensitive adhesive solution of the above composition to a dry film thickness of 15 μm with a comma coater, and apply a silicon separator B (“S” manufactured by Tokyo Cellophane Co., Ltd.)
(P-PET02) film thickness of 50 μm) was laminated.

(Preparation of Hologram Recording Film) Polyethylene terephthalate film (PET film: 50)
μm) / hologram recording material layer (film thickness 15 μm) / PE
A hologram recording film (HRF800x001; manufactured by DuPont) composed of a laminate of T films is 476n thick.
After recording a color Lippmann hologram with lasers having respective wavelengths of m, 532 nm and 647 nm,
The PET film was peeled off, a pressure-sensitive adhesive sheet (H225E, manufactured by San-A Kaken Co., Ltd.) having a removable pressure-sensitive adhesive layer was laminated, and heat-treated at 120 ° C. for 24 minutes.

The glass transition point of this volume hologram layer is
It was 46 ° C., and the dynamic storage modulus at 50 ° C. in the measurement of 6.28 rad / s was 6.28 × 10 ⁶ Pa.

(Preparation of hologram laminate) The peelable pressure-sensitive adhesive sheet was peeled off from the hologram recording film obtained above, and then the silicon separator A / first pressure-sensitive adhesive layer / silicon separator B was replaced with silicon separator A Is peeled off, the two are laminated, and the PET film /
A hologram recording material / first pressure-sensitive adhesive layer / silicon separator B was obtained.

The PET film was peeled from the laminate,
Further, the transparent protective film / second pressure-sensitive adhesive layer / silicon separator of the above-obtained transparent protective film / second silicon pressure-sensitive adhesive layer was peeled off, and the two were laminated to form a transparent protective film / second pressure-sensitive adhesive layer / hologram recording material / first pressure-sensitive adhesive layer / A volume hologram laminate label of the present invention comprising a silicon separator B was obtained. When the spectral characteristics of the hologram were evaluated, the half width was 17 to 20 nm.

Next, the silicon separator B in this label was peeled off and affixed on a paper substrate,
It was stored for 3 days at 0.1 ° C. and 0.12 kg / cm ² .

The hologram after storage is transferred to a three emission line fluorescent tube (Hilmic N FL4EX-N-PK: manufactured by Hitachi, Ltd.).
When the hologram defect was visually evaluated at an angle at which the defect looks darkest under the following condition, the defect level of the hologram was 1.5, and the storage stability was excellent.

The defect level is defined as 0 when there is no patch-like hologram defect, and the size (mm) and density (relative values 1 to 10) of the spots generated are visually evaluated.
The product was taken as the defect level. Those having a defect level of 3 or less have excellent storage stability.

(Comparative Example 1) (Preparation of Transparent Protective Film / Second Adhesive Layer / Silicon Separator) On a silicon separator (Tokyo Cellophane Co., Ltd. “SP-PE05” film thickness 50 μm), the following composition: acrylic 100 parts by weight ・ Methyl ethyl ketone ・ ・ ・ 30 parts by weight ・ Toluene ・ ・ ・ 15 parts by weight ・ Ethyl acetate ・ ・ ・ 15 parts by weight In the same manner as in Example 1, a transparent protective film / second pressure-sensitive adhesive layer / silicon separator was produced.

When the surface viscoelasticity of the pressure-sensitive adhesive layer was measured in the same manner as in Example 1, the maximum value of the logarithmic decrement was 1.4.

(Silicone separator A / first pressure-sensitive adhesive layer /
Production of silicon separator B) Silicon separator A
(Tokyo Cellophane “SP-PET05” film thickness 5
0 μm), immediately apply a pressure-sensitive adhesive solution of the above composition to a dry film thickness of 15 μm with a comma coater, and apply a silicon separator B (“S” manufactured by Tokyo Cellophane Co., Ltd.)
(P-PET02) film thickness of 50 μm) was laminated.

Thereafter, a volume hologram laminate label was produced in the same manner as in Example 1.

After a volume hologram laminate was produced in the same manner as in Example 1, the same hologram was stored and visually evaluated for hologram defects. As a result, spot-like spot defects were generated in the hologram, and the defect level was 10.8. Had a problem with storage stability.

Example 2 (Preparation of Transparent Protective Film / Second Adhesive Layer / Silicon Separator) On a silicon separator (Tokyo Cellophane Co., Ltd. “SP-PE05” film thickness 50 μm), the following composition: acrylic 100 parts by weight-Methyl ethyl ketone ... 30 parts by weight-Toluene ... 15 parts by weight-Ethyl acetate ... 15 parts by weight Was immediately applied with a comma coater so as to have a dry film thickness of 20 μm. A polyethylene terephthalate film (Lumirror T-60, manufactured by Toray Industries, Inc.)
(A film thickness of 50 μm) was laminated.

When the surface viscoelasticity of this pressure-sensitive adhesive layer was measured, the maximum value of the logarithmic decrement was 2.8.

(Silicone separator A / first pressure-sensitive adhesive layer /
Production of silicon separator B) Silicon separator A
(Tokyo Cellophane “SP-PET05” film thickness 5
0 μm), immediately apply a pressure-sensitive adhesive solution of the above composition to a dry film thickness of 15 μm with a comma coater, and apply a silicon separator B (“S” manufactured by Tokyo Cellophane Co., Ltd.)
(P-PET02) film thickness of 50 μm) was laminated.

Thereafter, in the same manner as in Example 1, a volume hologram laminate label was produced.

Then, a volume hologram laminate was prepared and stored in the same manner as in Example 1, and the hologram defect was visually evaluated. The hologram defect level was 0.25. It was excellent.

Example 3 In Example 1, the acrylic pressure-sensitive adhesive (“Nissetsu PE-118” manufactured by Nippon Carbide Co.) in the pressure-sensitive adhesive solution was replaced with an acrylic pressure-sensitive adhesive (“Nissetsu PE-123” manufactured by Nippon Carbide Co.). ")
Further, a volume hologram laminate label was produced in the same manner as in Example 1 except that the isocyanate-based crosslinking agent was changed to 8 parts by weight.

When the surface viscoelasticity of the second pressure-sensitive adhesive layer was measured, the maximum value of the logarithmic decrement was 0.776.

Then, a volume hologram laminate was prepared and stored in the same manner as in Example 1, and the hologram defects were visually evaluated. The hologram defect level was 2.1 and the storage stability was 2.1. It was excellent.

(Example 4, Comparative Examples 2, 3) Example 1 was repeated except that the amounts of the adhesive component and the isocyanate-based crosslinking agent in the adhesive solution were changed as shown in Table 1 below. In the same manner as in Example 1, volume hologram laminate labels were produced.

[0091]

[Table 1]

The maximum value (Δmax) of the logarithmic decrement of the surface viscoelasticity of each second pressure-sensitive adhesive layer was measured in the same manner as in Example 1, and the results are shown in Table 2 below. Further, as in Example 1, a volume hologram laminate was prepared and stored in the same manner, and the results of visual evaluation of hologram defects are also shown in Table 2.

[0093]

[Table 2]

Reference Example Transparent protective film / second pressure-sensitive adhesive layer / silicon separator, and silicon separator A / first pressure-sensitive adhesive layer / silicon separator B as in Comparative Example 1.
Was prepared.

(Preparation of Hologram Recording Film) Polyethylene terephthalate film (PET film: 50)
μm) / hologram recording material layer (thickness: 20 μm) / polyvinyl chloride film: A lipman hologram was recorded on a hologram recording film (Omnidex 706; manufactured by DuPont) with a 514 nm argon laser, and then the polyvinyl chloride film was peeled off. Then, a color tuning film (CTF-75: manufactured by DuPont) was laminated on this surface, and heated at 100 ° C. for 15 minutes.

The volume hologram layer has a glass transition point of 4
2 ° C. and 5 in 6.28 rad / s measurement.
The dynamic storage modulus at 0 ° C. was 2.7 × 10 ⁶ Pa.

(Preparation of hologram laminate) The color tuning film was peeled off from the hologram recording film obtained above, and the silicon separator A / first pressure-sensitive adhesive layer / silicon separator B obtained above
Were peeled off, and both were laminated to obtain a PET film / hologram recording material / first pressure-sensitive adhesive layer / silicon separator B.

The PET film was peeled from the laminate,
Further, the transparent protective film / second pressure-sensitive adhesive layer / silicon separator of the above-obtained transparent protective film / second silicon pressure-sensitive adhesive layer was peeled off, and the two were laminated to form a transparent protective film / second pressure-sensitive adhesive layer / hologram recording material / first pressure-sensitive adhesive layer / A volume hologram laminate label of the present invention comprising a silicon separator B was obtained. When the spectral characteristics of the hologram were evaluated, the half width was 35 nm.

Next, the silicon separator B in this label was peeled off and adhered on a paper base material,
It was stored for 3 days at 0.1 ° C. and 0.12 kg / cm ² .

The hologram after storage is used as a three emission line fluorescent tube (Hilmic N FL4EX-N-PK: manufactured by Hitachi, Ltd.).
When a visual evaluation was performed under the following conditions, no hologram defect occurred.

FIG. 4 shows the relationship between the defect level of the hologram and the logarithmic decay rate (Δmax) obtained by measuring the surface viscoelasticity of the second adhesive layer. From this figure, it can be seen that the maximum value of the logarithmic decrement was less than 1 or 2 in the surface viscoelasticity measurement in the pendulum-type rigidity property test.
It can be seen that the defect level is low when the above is obtained.

[0102]

The volume hologram laminate and the label for producing the volume hologram laminate of the present invention are less likely to cause patchy hologram defects in the volume hologram layer even when stored in a pressurized state such as during storage. It is.

[Brief description of the drawings]

FIG. 1 is a diagram for explaining a volume hologram laminate of the present invention in a sectional view thereof.

FIG. 2 is a diagram showing a logarithmic decrement in a second pressure-sensitive adhesive layer.

FIG. 3 is a diagram for explaining a label for producing a volume hologram laminate of the present invention in a sectional view thereof.

FIG. 4 shows the logarithmic decay rate (Δm) obtained by measuring the hologram defect level and the surface viscoelasticity of the second adhesive layer.
ax).

[Explanation of symbols]

1 is a volume hologram laminate, 2 is a substrate, 3 and 4 are pressure-sensitive adhesive layers, 5 is a volume hologram layer, 6 is a surface protection film, 1
0 is a label for producing a volume hologram laminate, and 11 is a release sheet.

Claims (4)

[Claims] 1. A volume hologram laminate in which a first pressure-sensitive adhesive layer, a volume hologram layer, a second pressure-sensitive adhesive layer, and a surface protection film are sequentially laminated on a base material, wherein the volume hologram layer is a matrix polymer and a photopolymer. A hologram recorded on a recording material composed of a possible compound, having a glass transition point of 30 ° C. to 70 ° C. and 6.28 rad.
The dynamic storage modulus at 50 ° C. in 5 / s measurement is 5 × 10
⁵ Pa to ⁵ × 10 ⁷ Pa, and the second
A volume hologram laminate, wherein the pressure-sensitive adhesive layer has a maximum value of a logarithmic decrement of less than 1 or 2 or more in a surface viscoelasticity measurement in a pendulum-type rigidity property test. 2. The volume hologram laminate according to claim 1, wherein the half width of the diffracted light of the volume hologram recorded on the volume hologram layer is 30 nm or less. 3. A recording medium comprising a first pressure-sensitive adhesive layer, a volume hologram layer, a second pressure-sensitive adhesive layer, and a surface protection film sequentially laminated on a release sheet, wherein the volume hologram layer comprises a matrix polymer and a photopolymerizable compound. A hologram recorded on a material having a glass transition point of 30 ° C. to 70 ° C.
C. and a dynamic storage modulus at 50 ° C. in 6.28 rad / s measurement of 5 × 10 ⁵ Pa to ⁵ × 10 ⁷ Pa, and the second pressure-sensitive adhesive layer has a pendulum-type rigidity. A label for producing a volume hologram laminate, wherein a maximum value of a logarithmic decrement is less than 1 or 2 or more in a surface viscoelasticity measurement in a physical property test. 4. The label for producing a volume hologram laminate according to claim 3, wherein the half width of the diffracted light of the volume hologram recorded in the volume hologram layer is 30 nm or less.