JP2001092359A - Repeelable tacky adhesive hologram label - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a repeelable tacky adhesive hologram label which does not allow the tacky adhesive, etc., of the hologram label to remain and does not leave damage, such as swelling and clouding, in an information display window of a portable information apparatus when the label is stuck to the information display window and is peeled after the lapse of a specified period. SOLUTION: The hologram label is characterized in that a transparent protective base material, tacky adhesive layer, volume hologram layer, tacky adhesive layer, transparent base material, repeelable tacky adhesive layers and sheet for peeling are laminated in this order from above, the repeelable tacky adhesive layer does not contain a plasticizer and monomer and the peeling strength is 10 to 1,000 g/25 mm.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a removable hologram label to be attached to the surface of an information display window. More specifically, the present invention relates to a hologram label in which a removable pressure-sensitive adhesive layer is improved, has good removability even after a certain period of time, and does not leave damage such as swelling or cloudiness on the surface of an information display window.

[0002]

2. Description of the Related Art A hologram capable of reproducing a three-dimensional image by using light interference can be processed into a hologram label having an adhesive processing and a release sheet. These hologram labels are attached to a target object after the release sheet is peeled off.

[0003] Specifically, cards, video cassettes, compact discs, branded products, CD-
It is attached to software such as a ROM, a ROM board, or the like. In this case, the manufacturer of the object to be attached is attached during the manufacturing process. It is also used by attaching it to an information display window such as a display window of a mobile phone, swimming goggles or ski goggles, or a display window of audio equipment. In this case, when the manufacturer of the sticking itself in the manufacturing process,
Consumers may attach the product after purchasing it.

[0004] Among the above-mentioned applications, in particular, mobile phones, PHS
When using it for portable information devices such as
A hologram label on which information such as graphic art is recorded is affixed to the information display window, and it is suitable for use because it can increase the design and eye catching properties, and can provide the function of restricting the viewing angle and preventing peeping. Have been.

[0005]

Conventionally, when such a hologram label is stuck to an information display window of a portable information device, if the hologram label is to be peeled off after a certain period of time, the hologram label will not be peeled off cleanly. Some of the medicine remained. The information display window of portable information devices is generally made of various resins for impact resistance and weight reduction. After attaching the hologram label to this information display window and peeling it off after a certain period, the information display window There were problems such as swelling of the window and clouding.

The present invention has been made in view of such circumstances, and has as its object to adhere a hologram label to an information display window of a portable information device and to remove the hologram label after a certain period of time. It is an object of the present invention to provide a removable adhesive hologram label which does not leave an adhesive or the like and does not leave damage such as swelling or cloudiness on an information display window.

[0007]

Means for Solving the Problems As a result of intensive studies to solve the above-mentioned problems, the present inventors have completed the following invention.

According to a first aspect of the present invention, a volume hologram layer, formed on one surface of the volume hologram layer, has both characteristics of sticking to a surface of an information display window and removability after a predetermined period. And a hologram label comprising a removable adhesive layer.

[0009] The second invention is a transparent protective substrate from the top,
The present invention relates to a hologram label according to the first invention, in which an adhesive layer, a volume hologram layer, an adhesive layer, a transparent substrate, a removable adhesive layer, and a release sheet are laminated in this order.

[0010] A third invention provides a transparent protective substrate,
The present invention relates to a hologram label according to the first invention, in which an adhesive layer, a volume hologram layer, a removable adhesive layer, and a release sheet are laminated in this order.

A fourth invention is the first to third inventions, wherein
The present invention relates to a hologram label wherein the removable pressure-sensitive adhesive layer does not contain a plasticizer and a monomer.

A fifth invention is the invention according to the first to fourth inventions, wherein
The present invention relates to a hologram label having a peel strength of 10 to 1000 g / 25 mm.

A sixth invention is a portable information terminal, a portable telephone,
The present invention relates to the hologram labels according to the first to fifth aspects of the present invention which are applied to information display windows of portable information devices such as PHS and pagers.

In a seventh aspect, the volume hologram layer includes:
A hologram label according to the first to sixth aspects of the invention, in which information that needs to be updated in a timely manner, such as a calendar, notification information, and a timetable, is recorded.

[0015]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a sectional view of one embodiment of the hologram label of the present invention. The hologram label of FIG. 1 includes a transparent protective substrate 3, an adhesive layer 2, a volume hologram layer 1, an adhesive layer 4, a transparent substrate 5, a removable adhesive layer 6, and a release sheet 7 from above. They are stacked in order.

FIG. 2 shows a cross section of another embodiment of the hologram label of the present invention. In the hologram label of FIG. 2, a transparent protective substrate 3, an adhesive layer 2, a volume hologram layer 1, a removable adhesive layer 6, and a release sheet 7 are laminated in this order from the top.

A specific example of the use of the hologram label as shown in FIGS. 1 and 2 will be described below. In the hologram label of the present application, some information is recorded on the hologram layer. As an example, information such as graphic art is recorded on a hologram label, and is used to adhere to an object to improve design and eye catching.

When information is recorded on the hologram layer of the hologram label so that pictures and characters are reproduced only when viewed obliquely, the display pattern of the information display window behind the hologram label only when viewed substantially from the front. When viewed obliquely, pictures and characters on the hologram label can be seen and the display pattern of the information display window behind the hologram label cannot be read, so that a peeping prevention function can be provided.

The hologram layer of the hologram label may record information that needs to be updated in a timely manner, such as a calendar, notice information, and a timetable. Since the hologram label on which such information is recorded needs to be periodically replaced, it is suitable as an applicable object of the removable adhesive hologram label of the present invention.

Next, each layer of the hologram laminate will be described in detail.

1. Removable adhesive layer As the adhesive constituting the removable adhesive layer 6 of the present application,
For example, acrylic resin, acrylate resin, or a copolymer thereof, styrene-butadiene copolymer, natural rubber, casein, gelatin, rosin ester,
Examples include terpene resins, phenolic resins, styrene resins, coumarone indene resins, polyvinyl ethers, silicone resins, and the like.

Using the above material, the removable pressure-sensitive adhesive layer 6
When the composition is constituted, it is desirable not to include a plasticizer, a monomer, and a low-polymerizable compound, and it is preferable to constitute only a polymer material component such as a polymer. Typically,
The pressure-sensitive adhesive layer is used to obtain desired physical properties and adhesiveness.
In many cases, low molecular weight components such as plasticizers and monomers are intentionally added. However, the display window of the portable information device to which the hologram label of the invention of the present application is attached is mostly made of a transparent resin for reasons of weight reduction, impact resistance, and the like. Many resin components are easily attacked by commonly used plasticizers and monomers. In particular, when these transparent resins are used for display windows of portable information devices, the surface swells or turbids slightly,
The display pattern behind it becomes difficult to see. Therefore, it is desirable that the removable pressure-sensitive adhesive layer 6 does not include low molecular weight components such as a plasticizer, a monomer, and a low polymerizable compound (about a dimer to a pentamer) in its composition. As the material for the removable pressure-sensitive adhesive layer, a colorless and transparent material is preferable.

The removable pressure-sensitive adhesive layer is preferably formed using the above-mentioned materials so as to have a thickness of 4 to 100 μm. The peel strength of the removable pressure-sensitive adhesive layer can be used in the range of 10 g / 25 mm to 1000 g / 25 mm with respect to the adhered substrate, and more preferably, 50 g / 2.
It is 5 mm to 500 g / 25 mm. This peel strength is 1
If it is smaller than 0 g / 25 mm, it is easily peeled off by an external force, which is a problem. If it exceeds 1000 g / 25 mm, a problem such as the adhesive remaining on the base material when removing the peeling occurs.

2. Volume hologram layer The volume hologram layer 1 is configured to transmit the interference light between the object light and the reference light,
The three-dimensional structure of the interference fringes is recorded as it is on a photosensitive material sufficiently thicker than the interval between the interference fringes. In order to form the volume hologram, the interference light between the object light and the reference light is directly recorded on the material layer for forming the volume hologram, or the volume hologram is obtained by copying by exposing the master plate to close contact. Industrially, the latter method is used.

Generally, the hologram-forming material includes:
Known volume hologram recording materials such as a silver salt material, a dichromated gelatin emulsion, a photopolymerizable resin, and a photocrosslinkable resin may be mentioned. In the case of a volume hologram, a matrix polymer and a photopolymerizable It is preferable to use a photosensitive material for dry volume phase hologram recording, which comprises a compound, a photopolymerization initiator and a sensitizing dye, as a material for forming a volume hologram. Specific materials include HR
F800X001-15 (manufactured by DuPont) and Omnidex 706 (manufactured by DuPont) are preferably used.

The hologram photosensitive material as described above is exposed using a laser beam. Specifically, 4
A full-color hologram can be obtained by performing exposure using laser light of a bright line having a wavelength of 76.5 nm, 532 nm, or 647 nm. Then, at 120 ° C,
After a post-processing step of 120 minutes, a stable hologram is obtained.

3. Adhesive layer As the adhesive constituting the adhesive layers 2 and 4 of the present application, for example, acrylic resin, acrylate resin, or a copolymer thereof, styrene-butadiene copolymer, natural rubber, casein, gelatin, Rosin esters, terpene resins, phenolic resins, styrene resins, coumarone indene resins, polyvinyl ethers, silicone resins, etc. are also exemplified.Also, α-cyanoacrylate, silicone, maleimide, styrene, polyolefin, polyvinyl An adhesive such as an ether-based adhesive may be used.

As the other pressure-sensitive adhesive, in addition to the above, a heat seal may be used. For example, ethylene-vinyl acetate copolymer resin, polyamide resin, polyester resin, polyethylene resin, ethylene-isobutyl acrylate copolymer resin, butyral resin, polyvinyl acetate and its copolymer resin, cellulose derivative, polymethyl methacrylate resin, Examples thereof include a polyvinyl ether resin, a polyurethane resin, a polycarbonate resin, a polypropylene resin, an epoxy resin, and a phenol resin. Alternatively, a thermoplastic elastomer such as SBS (styrene-butadiene-styrene block copolymer), SIS (styrene-isoprene-styrene block copolymer), SEBS (styrene-ethylene-butylene-styrene block copolymer), or a reactive hot melt resin is used. May be used. The material for the pressure-sensitive adhesive layer is preferably a colorless and transparent material.

The pressure-sensitive adhesive layer is preferably formed using the above-mentioned materials so as to have a thickness of 4 μm to 20 μm.
There are several methods for applying and bonding an adhesive, one of which is applied to one or both sides of the adhesive surface, dried if necessary, and then press-bonded. There is a way. At the time of press bonding, heating may be performed if necessary. Alternatively, a pressure-sensitive adhesive is applied to the releasable surface of a sheet, the surface of which is called a separator, and the pressure-sensitive adhesive is applied to one of the adhesive surfaces. There is also a method of crimping the bonding surface.

4. Transparent protective substrate, transparent substrate As a material that can be used for the transparent protective substrate 3 and the transparent substrate 5 of the present application, the thickness is 1 μm to 1 mm, preferably 10 μm.
m-100 μm polyethylene terephthalate film, polyethylene film, polypropylene film,
A resin film having high transparency and high smoothness such as a polyvinyl chloride film, an acrylic film, a triacetyl cellulose film, a cellulose acetate butyrate film and the like can be used. Among them, a colorless and transparent film is most preferable. Then, these films are bonded to the pressure-sensitive adhesive layer with a rubber roller or the like.

5. Release Sheet The release sheet 7 is obtained by coating at least one surface of a substrate with a release agent such as a silicone-based, fluorine-based, stearic acid-based, or wax-based release agent by a coating method, a dipping method, or the like. As the base material of the release sheet, various papers, polyethylene film, polypropylene film, polyvinyl fluoride film, polyvinylidene fluoride film, 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, polyester film such as polyethylene terephthalate film, polyimide film and the like can be used, especially Polyethylene terephthalate films are preferred. Further, the thickness of the base material of the release sheet is preferably 2 μm to 200 μm, and more preferably 10 μm to 50 μm.

As the base material of the release sheet, a white or colored paper, a colorless transparent, a colored transparent, or a colored opaque film may be used. Alternatively, it may be colored by printing on white paper or film. And
The color may be further printed on a colored paper or colored film other than white. The print pattern is solid printing, full-size printing of a pattern with an appropriate halftone dot area, gradation pattern printing, character pattern printing, geometric pattern printing,
It is also preferable to improve the design effect and the visibility by pattern printing or a combination thereof. Further, a pigment and a dye may be mixed in a release agent applied to the release sheet to be colored. When a colored release sheet is used, the visibility of the hologram is improved, so that the inspection efficiency in the production process of the hologram label is improved, and the design at the time of sale can be improved. In general, the darker the peeling sheet is colored, regardless of the state of the background, the hologram,
The visibility becomes good. In particular, a black and opaque state is preferable because the hologram can be most visually recognized.

[0034]

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples.

Example 1 a) Formation of Volume Hologram Layer On a polyethylene terephthalate (PET) film,
Hologram recording material (20 μm thick, Omnidex 7
06; manufactured by DuPont), and a volume hologram was recorded on a hologram recording medium in which polyvinyl chloride films were sequentially laminated. The hologram image was recorded so as to form a correct three-dimensional image when observed from the polyvinyl chloride film side.

B) Preparation of Release Sheet / Removable Adhesive Layer On a release sheet (silicon separator having a thickness of 50 μm, SP-PET; manufactured by Tokyo Cellophane Paper Co., Ltd.), a removable adhesive having the following composition was applied. A coating having a dry film thickness of 10 μm was prepared. Composition Acrylic adhesive (SK Dyne 1473H; Soken Chemical Co., Ltd.) 100 parts by weight Curing agent (L45; Soken Chemical Co., Ltd.) 3 parts by weight * Excluding low molecular weight components such as monomers, plasticizers and low polymerizable compounds.

C) Preparation of transparent protective substrate / adhesive layer Silicone separator (film thickness 50 μm, SP-PE
T; made by Tokyo Cellophane Paper Co., Ltd.)
E-118; manufactured by Nippon Carbide Co.)
And a non-stretched ethylene-vinyl alcohol copolymer film (thickness: 12μ) as a transparent protective substrate on the adhesive surface.
m, EVAL EF-F; manufactured by Kuraray Co., Ltd.).

D) Preparation of transparent substrate / pressure-sensitive adhesive layer Silicone separator (film thickness 50 μm, SP-PE
T; made by Tokyo Cellophane Paper Co., Ltd.)
E-118; manufactured by Nippon Carbide Co.)
, And a polyethylene terephthalate film (film thickness 50 μm, Lumirror T-
60; manufactured by Toray Industries, Inc.).

E) Preparation of hologram laher After peeling off the polyvinyl chloride film of the hologram recording material obtained in a) above, peeling off the silicone separator / adhesive layer / silicone separator of transparent substrate obtained in d) above. The two were laminated to obtain a PET film / volume hologram layer / adhesive layer / transparent substrate. Thereafter, the removable pressure-sensitive adhesive layer / release sheet obtained in b) above is laminated, and a laminate of PET film / volume hologram layer / pressure-sensitive adhesive layer / transparent substrate / removable pressure-sensitive adhesive layer / release sheet is laminated. And

The PET film of the laminate was peeled off, and the transparent protective substrate / adhesive layer / silicone separator of the silicone separator obtained in c) above was peeled off.
The two are laminated, and a transparent protective substrate / pressure-sensitive adhesive layer / volume hologram layer / pressure-sensitive adhesive layer / transparent substrate / removable pressure-sensitive adhesive layer /
A hologram label of the present invention comprising a release sheet was obtained.

The peel strength of the hologram label was measured under the following conditions. The adherend used a plate material of polymethyl methacrylate (PMMA).

Peel strength measurement conditions (180 ° peel test specified in JIS Z0237) Measuring device: SV-201-E tensile / compression tester (manufactured by Konno Seisakusho Co., Ltd.) Measuring atmosphere: 25 ° C., 65% RH Test piece: 25 mm width-Lamination: 2 kg rubber roller pressed and reciprocated with one reciprocation-Lamination time: 60 minutes after lamination-Peeling angle: 180 °-Peeling speed: 250 mm / min

The peel strength was measured under the above measurement conditions, and was found to be 100 g / 25 mm.

After the release sheet was released from the hologram label, it was adhered to an information display window (material: PMMA) of a mobile phone as an adherend. When the hologram label was peeled after 7 days, the hologram label could be peeled cleanly from the information display window, and no adhesive residue or the like was generated. Further, the information display window did not suffer any damage such as swelling or cloudiness.

(Comparative Example 1) As a removable adhesive, PL
Example 1 except that Shin (manufactured by Lintec Corporation) was used.
A hologram label was produced in the same manner as described above. The peel strength of the hologram label measured under the same conditions as in Example 1 was 1200 g / 25 mm. After the peeling sheet was peeled from the hologram label, it was adhered to an information display window (material: PMMA) of a mobile phone as an adherend. When peeled after 7 days, it was difficult to remove the adhesive remaining on the information display window.

(Comparative Example 2) As a removable adhesive, 2-
A hologram label was prepared in the same manner as in Example 1, except that 50 parts by weight of ethylhexyl acrylate resin and 50 parts by weight of butyl acrylate resin were mixed with 20 parts by weight of isopropyl myristate as a plasticizer. The peel strength of this hologram label was measured under the same conditions as in Example 1, and as a result, it was 750 g / 25 mm. After peeling off the release sheet from the hologram label, an information display window of a mobile phone (material:
PMMA). When peeled after 7 days, the hologram label can be peeled off neatly from the information display window,
No adhesive residue or the like was generated. However, the information display window
It was swollen by the plasticizer in the removable pressure-sensitive adhesive layer, and when touched with a finger, a white finger mark remained on the surface softened by the swelling.

[0047]

As described in detail above, the hologram label of the present invention has a peel strength of the re-peelable pressure-sensitive adhesive layer of 10 to 100.
Since it is 0 g / 25 mm, when a hologram label is attached to the information display window of a portable information device and peeled off after a certain period of time, the label can be peeled off without leaving any adhesive or the like. Since the removable adhesive layer does not contain a plasticizer and a monomer, no damage such as swelling or clouding remains on the information display window after the hologram label is removed.

[Brief description of the drawings]

FIG. 1 is a sectional view showing one embodiment of a hologram label of the present invention.

FIG. 2 is a sectional view showing another embodiment of the hologram label of the present invention.

[Explanation of symbols]

 1. 1. Volume hologram layer Adhesive layer 3. Transparent protective substrate 4. Adhesive layer 5. Transparent substrate 6. 6. Removable pressure-sensitive adhesive layer Release sheet

Claims (7)

[Claims] 1. A volume hologram layer and a removability formed on one surface of the volume hologram layer and having both properties of sticking to the surface of an information display window and removability after a predetermined period. A hologram label comprising an adhesive layer. 2. The method according to claim 1, wherein a transparent protective substrate, a pressure-sensitive adhesive layer, a volume hologram layer, a pressure-sensitive adhesive layer, a transparent substrate, a removable pressure-sensitive adhesive layer, and a release sheet are laminated in this order from the upper side. Hologram label. 3. The hologram label according to claim 1, wherein a transparent protective substrate, a pressure-sensitive adhesive layer, a volume hologram layer, a removable pressure-sensitive adhesive layer, and a release sheet are laminated in this order from the upper side. 4. The hologram label according to claim 1, wherein the removable pressure-sensitive adhesive layer does not contain a plasticizer and a monomer. 5. The method according to claim 1, wherein the peel strength is 10%.
A hologram label characterized by being 1000 g / 25 mm. 6. The hologram label according to claim 1, which is adapted to an information display window of a portable information device such as a portable information terminal, a portable telephone, a PHS, a pager, and the like. 7. The hologram label according to claim 1, wherein information such as a calendar, notice information, a timetable, etc., which needs to be updated in a timely manner, is recorded on said volume hologram layer.