JP4974261B2 - Optical member - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an optical member in which a release sheet and / or a protective film with an adhesive are attached to an adhesive optical film having an adhesive layer on one surface of the optical film. Examples of the optical film constituting the optical member include a polarizing film, a retardation film, an optical compensation film, a brightness enhancement film, an antiglare sheet, or a laminate of these, and the optical film is an adhesive optical film. Used in liquid crystal display devices and the like.
[0002]
[Prior art]
In the liquid crystal display, it is indispensable to arrange polarizing elements on both sides of the glass substrate that forms the outermost surface of the liquid crystal panel because of its image forming method. Generally, a polarizing film is attached to the outermost surface of the liquid crystal panel. ing. In addition to the polarizing film, various optical elements have been used on the outermost surface of the liquid crystal panel in order to improve the display quality of the display. For example, a retardation film for preventing coloring, a viewing angle widening film for improving the viewing angle of a liquid crystal display, and a brightness enhancement film for increasing the contrast of the display are used. These films are collectively called optical films.
[0003]
When sticking the optical film on the outermost surface of the liquid crystal panel, an adhesive is usually used. In addition, since the optical film can be instantly fixed to the outermost surface of the liquid crystal panel and has a merit such that a drying process is not required to fix the optical film, the adhesive is preliminarily attached to one side of the optical film. It is provided as. That is, an adhesive optical film is generally used for attaching the optical film to the outermost surface of the liquid crystal panel. A release sheet is attached to the pressure-sensitive adhesive layer of the pressure-sensitive adhesive optical film for protection until the optical film is attached to the liquid crystal panel. On the other hand, a protective film is attached to the surface of the optical film serving as the liquid crystal display surface in order to protect the optical film surface until the liquid crystal cell is assembled.
[0004]
As described above, the adhesive optical film is used as an optical member in which a release sheet is attached to the adhesive layer surface and a protective film is provided on the other surface. The said optical member is cut | disconnected by the shape and magnitude | size according to various uses according to various uses. In the conventional optical member, as shown in FIG. 4, all of the adhesive optical film composed of the optical film 1 and the adhesive layer 2, the release sheet 3, and the protective film 4 with adhesive are cut with the same dimensions. It was.
[0005]
The optical members are usually stacked and stored. However, when the optical members have the same dimensions, the adhesion between the optical members becomes strong, and there is a problem that the optical members block in the laminated state. For this reason, when the panels are attached, when the optical members are taken out from the stacked state one by one, the optical members stacked below may be lifted (stacked) together, which hinders continuous production. There is a risk of escaping. In addition, the release sheet and the protective film with adhesive are finally peeled off from the adhesive optical film. However, if all of the optical members have the same dimensions, the peeling becomes heavy (heavy peeling) and cannot be peeled off. There is also a problem. Furthermore, since the adhesive layer is exposed on the cut side surface of the optical member cut with the same dimensions, the adhesive member protrudes from the adhesive layer when the optical member is stacked or transported. May occur.
[0006]
[Problems to be solved by the invention]
The present invention is an optical member in which a release sheet and / or a protective film with an adhesive is attached to an adhesive optical film having an adhesive layer on one surface of the optical film, and has a blocking problem The object is to provide an optical member having good releasability. Furthermore, it aims at providing the optical member without the glue stain | pollution | contamination by an adhesion layer, a glue defect | deletion, etc.
[0007]
[Means for Solving the Problems]
As a result of intensive studies to solve the above problems, the present inventors have found that the above object can be achieved by the optical member shown below, and have completed the present invention.
[0008]
That is, according to the present invention, a release sheet is attached to the adhesive layer of the adhesive optical film having an adhesive layer on one surface of the optical film, or a protective film with an adhesive is provided on the other surface of the optical film. an optical member which is attached, the shape of the pressure-sensitive adhesive optical film is rectangular, the length of one side is 20 to 500 mm, the protective film with a release sheet or pressure-sensitive adhesive that is the attached The present invention relates to an optical member characterized in that the size exceeds the size of the adhesive optical film by a width of 0.05 to less than 1 mm in part or all of the peripheral edge of the adhesive optical film.
[0009]
In the present invention, a release sheet is attached to the adhesive layer of the adhesive optical film having an adhesive layer on one surface of the optical film, and a protective film with an adhesive is provided on the other surface of the optical film. It is an attached optical member, and the shape of the adhesive optical film is a quadrangle, the length of one side thereof is 20 to 500 mm, and at least one of the release sheet and the protective film with an adhesive The present invention relates to an optical member characterized in that the size exceeds the size of the adhesive optical film by a width of 0.05 to less than 1 mm in part or all of the peripheral edge of the adhesive optical film.
[0010]
In the optical member of the present invention, the size of the release sheet attached to protect the adhesive layer and / or the protective film with adhesive attached to protect the optical film surface exceeds the size of the adhesive optical film. The ends of the adhesive optical film and the release sheet and / or the protective film with adhesive are not in the same position. For this reason, even when optical members are laminated, the adhesion is weakened and blocking is suppressed, and when the optical members are attached to the panel, it is possible to prevent the optical members from being laminated. Further, since the size of the release sheet and / or the protective film with adhesive is larger than the size of the adhesive optical film, the surface adhesion is weakened, the peelability is good, and there is no problem of heavy peeling. Furthermore, when the release sheet has an excessive size, glue stains and glue defects due to exposure on the cut side surface of the adhesive layer are suppressed, and good surface stain resistance is exhibited. In order to prevent the surface contamination preventive property due to the adhesive layer, it is preferable that the release sheet is set to an excess size of the adhesive optical film in the entire peripheral edge of the adhesive optical film.
[0011]
In the optical member, the size of the release sheet and / or the protective film with adhesive that exceeds the size of the adhesive optical film is the size of the adhesive optical film in part or all of the peripheral edge of the adhesive optical film. Is preferably exceeded by a width of 0.05 to 5 mm.
[0012]
The size and shape of the pressure-sensitive adhesive optical film are determined according to various applications, and the excess size of the release sheet and the protective film with adhesive is appropriately determined according to various applications. In order to effectively exhibit the releasability and the surface dirt prevention property, the excess size of the release sheet and the protective film with adhesive is preferably 0.05 mm or more, and more preferably 0.5 mm or more. On the other hand, the excess size of the release sheet and the protective film with pressure-sensitive adhesive is preferably 5 mm or less, more preferably 1 mm or less, from the viewpoint of preventing adhered sedimentation foreign matter and turning over the exposed portion by product handling.
[0013]
In the optical member, the pressure-sensitive adhesive optical film is a quadrangle, and a release sheet and / or a protective film with a pressure-sensitive adhesive that exceeds the size of the pressure-sensitive adhesive optical film is provided on at least two sides of the square. It is a preferable aspect that the size is exceeded.
[0014]
The pressure-sensitive adhesive optical film used for the liquid crystal display layer or the like is generally a quadrangle in accordance with the liquid crystal display layer or the like. In that case, the release sheet and the protective film with adhesive may be oversized in at least one part (for example, one side) of the quadrangle. It is preferable from the viewpoint of prevention of glue loss in It is preferable that the two sides are provided on opposite sides in terms of suiting the transport line. The release sheet and the protective film with pressure-sensitive adhesive have the same effects as the two sides when the three sides of the square are oversized. When the excess size is set on all four sides, the glue stain can be minimized, and it is possible to prevent the paste marks from remaining on the optical film laminate due to the protruding glue as much as possible.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
The optical member of the present invention will be described below with reference to the drawings. The optical member of this invention is shown by FIGS. 1-3, for example. 1 to 3 show that a release sheet 3 is attached to an adhesive layer 2 of an adhesive optical film composed of an optical film 1 and an adhesive layer 2 of the optical film 1, and adhesive is not applied to the surface of the optical film 1 where the adhesive layer 2 is not provided. It is a side view of the optical member to which the protective film 4 with an agent is attached. 1 to 3 exemplify the case where a release sheet 3 and a protective film 4 with an adhesive are provided, the release sheet 3 and the protective film 4 with an adhesive exceed the size of the adhesive optical film. The thing provided only in either one may be sufficient.
[0016]
FIG. 1 shows an example in which the size of the release sheet 3 exceeds the size of the adhesive optical film, and FIG. 2 shows an example in which the size of the protective film 4 with adhesive exceeds the size of the adhesive optical film. Yes, FIG. 3 is an example in which the size of both the release sheet 3 and the protective film 4 with adhesive exceeds the size of the adhesive optical film. In FIG. 1 to FIG. 3, “a” is an example of an excess size of the release sheet 3 and / or the protective film 4 with an adhesive, and is an example having an excess size on at least two opposite sides.
[0017]
FIG. 5 is an example of a top view of FIG. 1, and the release sheet 3 has an excess size a on four sides. In addition, although the excess size a is determined according to the various uses for which the adhesive optical film is used, as described above, it is preferably about 0.05 to 5 mm. In particular, when the shape of the pressure-sensitive adhesive optical film is a quadrangle and the length of one side is about 20 to 500 mm, the excess size is preferable. In addition, the excess size a may be the same width in all, and does not need to be the same width.
[0018]
The optical member of the present invention is not particularly limited as long as the size of the release sheet and / or the protective film with adhesive exceeds the size of the adhesive optical film. For example, FIG. This can be done by punching the optical member using the Thomson press blade mold shown. Conventionally, as a Thomson press blade type, a wooden mold 10 having only an outer punching blade 11 as shown in FIG. 7 has been used. Therefore, all the constituent materials of the obtained optical member were cut with the same dimensions as shown in FIG. On the other hand, the optical member of the present invention is manufactured using a wooden mold 10 having an outer punching blade 11 and an inner punching blade 12 as shown in FIG. By appropriately adjusting the installation location of the inner punching blade 12, it is possible to determine the excess size and the excess size of the release sheet and / or the protective film with adhesive. According to the Thomson press blade mold of FIG. 6, the optical member of the present invention having an excess size on the entire periphery (all four sides) can be obtained. In FIG. 6, a is a width for adjusting the excess size, and b is a thickness of the release sheet and / or the protective film with an adhesive, which is an excess size, according to the punching stroke (distance) of the Thomson press. Is adjusted so as not to be cut.
[0019]
The optical member shown in FIG. 1 is placed on the Thomson press blade mold shown in FIG. 6 so that the optical member before punching is placed with the release sheet 3 facing upward, and after pressing, the outer punch 11 and the inner punch It is obtained by removing the adhesive-coated protective film 4 and the adhesive optical film between the blades 12. The optical member shown in FIG. 2 is placed in the Thomson press blade mold shown in FIG. 6 so that the optical member before punching is placed so that the protective film 4 with adhesive is facing upward and pressed. It is obtained by removing the release sheet 3 and the adhesive optical film between the punching blades 12. In addition, in FIG. 2, although the case where the protective film with an adhesive (a thing containing the adhesive layer of a protective film) becomes an excess size is illustrated, it will become an excess size only about the protective film of an adhesive film with an adhesive. It can also be cut. The optical member shown in FIG. 3 is obtained by removing the protective film 4 with adhesive from the optical member shown in FIG. 1, and preparing it separately and replacing it with a protective film 4 with adhesive larger in size than the optical film 1. .
[0020]
The materials constituting the optical member of the present invention are as follows.
[0021]
(Optical film)
As the optical film 1, one used for forming a liquid crystal display device or the like is used, and the type thereof is not particularly limited. Examples of the optical film include a polarizing film, an elliptically polarizing film, a polarizing film having an optical compensation function, a polarizing film having a viewing angle expansion function, and a polarizing film having a brightness enhancement function. In these films, a retardation film, an optical compensation film, a brightness enhancement film, an antiglare sheet or the like is laminated on a polarizing film.
[0022]
It does not restrict | limit especially as a polarizer which comprises a polarizing film, Various things can be used. Examples of the polarizer include dichroic substances such as iodine and dichroic dyes on hydrophilic polymer films such as polyvinyl alcohol films, partially formalized polyvinyl alcohol films, and ethylene / vinyl acetate copolymer partially saponified films. Examples thereof include a polyene-based oriented film such as a stretched product obtained by adsorbing a substance, a dehydrated polyvinyl alcohol product or a dehydrochlorinated polyvinyl chloride product. The thickness of the polarizer is not particularly limited, but is generally about 5 to 80 μm.
[0023]
On one side or both sides of the polarizer, a transparent protective layer can be provided as a coating layer of a polymer or a laminate layer of a film for the purpose of water resistance. As the transparent polymer or film material for forming the transparent protective layer, an appropriate transparent material can be used, but a material excellent in transparency, mechanical strength, thermal stability, moisture barrier property and the like is preferably used. Although the thickness in particular of a transparent protective layer is not restrict | limited, About 10-300 micrometers is common.
[0024]
Examples of the material for forming the transparent protective layer include polyester polymers such as polyethylene terephthalate and polyethylene naphthalate, cellulose polymers such as cellulose diacetate and cellulose triacetate, acrylic polymers such as polymethyl methacrylate, polystyrene, acrylonitrile, Examples thereof include styrene polymers such as styrene copolymers (AS resins), polycarbonate polymers, and the like. In addition, polyethylene, polypropylene, polyolefins having a cyclo or norbornene structure, polyolefin polymers such as ethylene / propylene copolymers, vinyl chloride polymers, amide polymers such as nylon and aromatic polyamide, imide polymers, sulfone polymers , Polyether sulfone polymer, polyether ether ketone polymer, polyphenylene sulfide polymer, vinyl alcohol polymer, vinylidene chloride polymer, vinyl butyral polymer, arylate polymer, polyoxymethylene polymer, epoxy polymer, or the above Polymer blends and the like are also examples of the polymer that forms the transparent protective layer.
[0025]
Examples of the retardation film include a birefringent film obtained by uniaxially or biaxially stretching a polymer material, a liquid crystal polymer film, and the like. The thickness of the retardation film is not particularly limited, but is generally about 20 to 150 μm. The retardation plate can also be formed as a superposed body of stretched films of two or more layers and controlled optical characteristics such as retardation, and the liquid crystal cell is used for the purpose of preventing coloring and expanding the viewing angle range. It can also be used as an elliptically polarizing film formed by laminating with a polarizing film in order to compensate for the phase difference.
[0026]
Examples of the polymer material include polyvinyl alcohol, polyvinyl butyral, polymethyl vinyl ether, polyhydroxyethyl acrylate, hydroxyethyl cellulose, hydroxypropyl cellulose, methyl cellulose, polycarbonate, polyarylate, polysulfone, polyethylene terephthalate, polyethylene naphthalate, polyether sulfone, Polyphenylene sulfide, polyphenylene oxide, polyallylsulfone, polyvinyl alcohol, polyamide, polyimide, polyolefin, polyvinyl chloride, cellulose polymer, or binary, ternary copolymers, graft copolymers, blends Things are given. These polymer materials become oriented products (stretched films) by stretching or the like.
[0027]
Examples of the liquid crystalline polymer include various main chain types and side chain types in which a conjugated linear atomic group (mesogen) imparting liquid crystal alignment is introduced into the main chain or side chain of the polymer. It is done. Specific examples of the main chain type liquid crystalline polymer include, for example, a nematic alignment polyester liquid crystalline polymer, a discotic polymer, and a cholesteric polymer having a structure in which a mesogen group is bonded to a spacer portion that imparts flexibility. . Specific examples of the side chain type liquid crystalline polymer include polysiloxane, polyacrylate, polymethacrylate, or polymalonate as a main chain skeleton, and a nematic alignment imparting paraffin through a spacer portion composed of a conjugated atomic group as a side chain. Examples thereof include those having a mesogen moiety composed of a substituted cyclic compound unit. These liquid crystalline polymers are prepared by, for example, applying a solution of a liquid crystalline polymer on an alignment surface such as those obtained by rubbing the surface of a thin film such as polyimide or polyvinyl alcohol formed on a glass plate, or by obliquely depositing silicon oxide. This is done by developing and heat treatment.
[0028]
The polarizing film and the retardation film can be laminated and used, for example, a reflective polarizing film, a semi-transmissive layer polarizing film, and a polarized light separating polarizing film. Moreover, the optical film of the said illustration can also be used as an optical compensation film and other various viewing angle expansion films, Furthermore, a brightness improvement film etc. are mention | raise | lifted as an optical film. Moreover, a polarizing film can also provide an anti-glare sheet | seat by providing the reflection layer of a fine uneven structure on the surface.
[0029]
(Adhesive layer)
Examples of the pressure-sensitive adhesive that forms the pressure-sensitive adhesive layer 2 include rubber pressure-sensitive adhesives, acrylic pressure-sensitive adhesives, and silicone pressure-sensitive adhesives. Among these, acrylic pressure-sensitive adhesives are preferable. The pressure-sensitive adhesive may contain a crosslinking agent such as a polyisocyanate compound, a polyamine compound, a melamine resin, a urea resin, or an epoxy resin. Furthermore, the pressure-sensitive adhesive may be appropriately added with a tackifier, a plasticizer, a filler, an antioxidant, an ultraviolet absorber, a silane coupling agent, and the like as necessary without departing from the object of the present invention. It can also be used.
[0030]
The method for forming the adhesive layer 2 is not particularly limited, and includes a method of applying an adhesive (solution) to the optical film 1 and drying, a method of transferring the release sheet 4 provided with the adhesive layer 2 to the optical film 1, and the like. can give. Although the thickness of the adhesion layer 2 (dry film thickness) is not specifically limited, It is preferable to set it as about 10-40 micrometers.
[0031]
(Release sheet)
Examples of the constituent material of the release sheet 3 include paper, synthetic resin films such as polyethylene, polypropylene, and polyethylene terephthalate. The surface of the release sheet 3 may be subjected to a silicone treatment, a long-chain alkyl treatment, or a fluorine treatment, if necessary, in order to enhance the peelability from the adhesive layer 2.
[0032]
(Protective film with adhesive)
The protective film 4 with a pressure-sensitive adhesive is obtained by forming a pressure-sensitive adhesive layer 4 b on a base film 4 a, and the pressure-sensitive adhesive layer 4 b is adhered to the surface of the optical film 1. As the base film 4a, for example, a biaxially stretched film such as polypropylene or polyester can be preferably used. Although there is no restriction | limiting in particular about the thickness of the plastic film used as the base film 4a, Preferably it is about 10-200 micrometers, Especially 20-50 micrometers is preferable.
[0033]
As the pressure-sensitive adhesive constituting the pressure-sensitive adhesive layer 4b formed on one side of the base film 4a, any of acrylic, synthetic rubber, and rubber-based pressure-sensitive adhesives can be used. Easy acrylic adhesive is desirable. The pressure-sensitive adhesive may contain a crosslinking agent such as a polyisocyanate compound, a polyamine compound, a melamine resin, a urea resin, or an epoxy resin as a crosslinking agent. Furthermore, a tackifier, a plasticizer, a filler, an antioxidant, an ultraviolet absorber, a silane coupling agent, and the like can be appropriately used for the pressure-sensitive adhesive as necessary. The thickness (dry film thickness) of the adhesive layer 4b is not particularly limited, but is usually about 5 to 50 μm, preferably 5 to 30 μm.
[Brief description of the drawings]
FIG. 1 is a side view of an example of an optical member of the present invention.
FIG. 2 is a side view of an example of the optical member of the present invention.
FIG. 3 is a side view of an example of the optical member of the present invention.
FIG. 4 is a side view of a conventional optical member.
5 is a top view of the optical member of FIG. 1. FIG.
FIG. 6 is a schematic view of a Thomson press blade die used for manufacturing the optical member of the present invention.
FIG. 7 is a schematic view of a Thomson press blade die used for manufacturing a conventional optical member.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Optical film 2 Adhesive layer 3 Release sheet 4 Protective film a with adhesive a Excess size

Claims (3)

Optics or release sheet to the adhesive layer of the pressure-sensitive adhesive optical film is attached, or pressure-sensitive adhesive protective film on the other surface of the optical film is attached with an adhesive layer on one surface of the optical film The adhesive optical film has a quadrangular shape, the length of one side is 20 to 500 mm, and the size of the attached release sheet or the adhesive protective film is adhesive optical. An optical member characterized in that the size of the adhesive optical film is exceeded by a width of less than 0.05 to 1 mm in part or all of the peripheral edge of the film. An optical film in which a release sheet is attached to the adhesive layer of the adhesive optical film having an adhesive layer on one surface of the optical film, and a protective film with an adhesive is attached to the other surface of the optical film. The adhesive optical film has a quadrangular shape, a side length of 20 to 500 mm, and at least one of the release sheet and the protective film with an adhesive is an adhesive type An optical member characterized in that the size of the adhesive optical film is exceeded by a width of 0.05 to less than 1 mm in part or all of the peripheral edge of the optical film. The release sheet and / or the protective film with an adhesive exceeding the size of the adhesive optical film exceeds the size of the adhesive optical film on at least two sides of the adhesive optical film that is a rectangle. The optical member according to claim 1 or 2 .

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