CN105319634B - Phase difference film - Google Patents

Abstract

A kind of phase difference film for being not easy to decline the brightness of display device is provided.A kind of phase difference film is laminated in the phase difference film: the resin layer (a) that refractive index is 1.50 or less, total light transmittance is 80% or more；Be 1.55 or more with refractive index, it is intrinsic it is birefringent be 0.07 or more, the resin layer (b) that total light transmittance is 80% or more, at least one layer of resin layer (a) is located at the outside of resin layer (b).

Description

Phase difference film

Technical field

The present invention relates to phase difference films.

Background technique

The phase difference film comprising polycarbonate is described in patent document 1.When the phase difference film is used for display device, have When decline the brightness of display device.

Existing technical literature

Patent document

Patent document 1: Japanese Unexamined Patent Publication 3-174512 bulletin

Summary of the invention

Problems to be solved by the invention

Polycarbonate it is intrinsic it is birefringent be 0.07 or more, therefore be easy to show phase difference, but refractive index be 1.55 with Upper height, therefore when being used as phase difference film in the presence of making the brightness of display device decline such problems.

The means used to solve the problem

The present invention includes following invention.

[1] a kind of phase difference film, be laminated in the phase difference film: refractive index is 1.50 or less, total light transmittance is 80% or more resin layer (a)；Be 1.55 or more with refractive index, it is intrinsic it is birefringent be 0.07 or more, total light transmittance is 80% or more resin layer (b), at least one layer of resin layer (a) are located at the outside of resin layer (b).

[2] phase difference film as described in [1], wherein resin layer (b) is Polycarbonate Layer.

[3] phase difference film as described in [1] or [2], wherein resin layer (a) is poly- (methyl) acrylate layer.

[4] such as described in any item phase difference films of [1]~[3], there is the optical characteristics indicated by following formula (1),

70 < Re (590) < 320 (1),

(Re (590) is indicated for phase difference value in the face of wavelength 590nm light.)

[5] as [1]~[4] described in any item phase difference films, wherein the volume fraction of resin layer (b) be 30~ 95%.

[6] such as described in any item phase difference films of [1]~[5], wherein resin layer (a) contains poly- (methyl) acrylic acid Ester and rubber elastomer particle.

[7] phase difference film as described in [6], wherein the number average bead diameter of rubber elastomer particle is 10~350nm.

[8] phase difference film as described in [6] or [7], wherein the content of the rubber elastomer particle in resin layer (a) is 3 Quality % or more and 60 mass % or less.

[9] such as described in any item phase difference films of [1]~[8], wherein being sequentially laminated with resin layer (a), resin layer (b) and resin layer (a).

It [10] is after resin layer (a) is stretched with resin layer (b) such as described in any item phase difference films of [1]~[9] Film.

[11] a kind of elliptical polarization plate, wherein being sequentially laminated with [1]~described in any item phase difference films of [7], gluing Oxidant layer and polarizing film.

[12] the elliptical polarization plate as described in [11], wherein gluing oxidant layer is active energy ray-curable adhesive Solidfied material.

Invention effect

According to the present invention it is possible to obtain the phase difference film for being difficult to make the brightness of display device to decline.

Detailed description of the invention

Fig. 1 is the schematic diagram for having the elliptical polarization plate of phase difference film of the invention.

Fig. 2 is the schematic diagram for having the elliptical polarization plate of phase difference film of the invention.

Specific embodiment

It, can as the resin contained in the resin layer (a) that refractive index is 1.50 or less, total light transmittance is 80% or more To enumerate fluororesin, polyvinyl resin, acrylic resin and poly- (methyl) acrylate etc., resin layer (a) is preferably containing poly- Poly- (methyl) acrylate layer of (methyl) acrylate.

Be 1.55 or more as refractive index, it is intrinsic it is birefringent be 0.07 or more, the tree that total light transmittance is 80% or more It is sub- can to enumerate polycarbonate, polyester, polyurethane, polyether sulfone, polyphenylene oxide, polyamide and polyamides for the resin contained in rouge layer (b) Amine etc., resin layer (b) are preferably the Polycarbonate Layer containing polycarbonate.

[resin layer (a)]

Resin layer (a) preferably also contains rubber elastomer particle.The rubber elastomer particle is comprising showing rubber bullet The particle of the layer (hereinafter sometimes referred to as rubber elastomer layer) of property.The rubber elastomer particle can be only by showing rubber bullet Property layer constitute particle, be also possible to show caoutchouc elasticity layer and other layers of multilayered structure particle.Table The layer for revealing caoutchouc elasticity includes rubber elastic polymers.As rubber elastic polymers, it can be cited for example that olefin-based is elastic Polymer, diene series elastomeric polymer, styrenic-diene system elastocopolymer, acrylic flexible polymer etc..Wherein, from , it is preferable to use acrylic acid series from the perspective of the light resistance and the transparency of phase difference film (hereinafter sometimes referred to as this film) of the invention Elastomeric polymer.

Acrylic flexible polymer can be made of the polymer based on alkyl acrylate.It can be propylene The homopolymer of acid alkyl ester is also possible to the alkyl acrylate and 50 mass % monomer furthermore below of 50 mass % or more Copolymer.As alkyl acrylate, the alkyl acrylate that the carbon atom number usually using its alkyl is 4~8.Make propylene In the case where monomer copolymerization other than acid alkyl ester, as its example, methyl methacrylate, methacrylic acid second can be enumerated The alkyl methacrylate of ester etc；The styrenic monomers of styrene, ring-alkylated styrenes etc；Acrylonitrile, metering system The monofunctional monomers such as the unsaturated nitrile of nitrile etc；And (methyl) allyl acrylate, (methyl) methallyl acrylate it Two alkenyl esters of the binary acid of the alkenyl ester of the unsaturated carboxylic acid of class, diallyl maleate etc, two (first of alkylene glycol Base) acrylate etc the polyfunctional monomers such as the unsaturated carboxylic acid diester of glycols.

Rubber elastomer particle comprising acrylic flexible polymer preferably has acrylic rubber flexible polymer The particle of the multilayered structure of the layer of object.Can specifically enumerate: acrylic rubber elastomeric polymer layer outside have with The double-layer structure of rigid polymeric nitride layer based on alkyl methacrylate；And in acrylic rubber elastomeric polymer The outside of layer has the rigid polymeric nitride layer based on alkyl methacrylate and also has in inside with metering system The three-decker of rigid polymeric nitride layer based on acid alkyl ester.Rigid polymeric nitride layer based on alkyl methacrylate The homopolymer that can be alkyl methacrylate is also possible to the alkyl methacrylate and 50 matter of 50 mass % or more Measure the copolymer of % monomer furthermore below.As alkyl methacrylate, the carbon atom number usually using the alkyl is 1 ~4 alkyl methacrylate, preferably methyl methacrylate.It is copolymerized the monomer other than alkyl methacrylate In the case of, as its example, the alkyl acrylate of methyl acrylate, ethyl acrylate etc can be enumerated；Styrene, alkyl The styrenic monomers of styrene etc；The unsaturated nitrile etc. of acrylonitrile, methacrylonitrile etc.The rubber of this multilayered structure Elastomer particle can for example be manufactured by method described in Japanese Patent Publication 55-27576 bulletin.

The number average bead diameter of rubber elastomer particle is preferably in the range of 10~350nm.It is formed as a result, in film surface small Bumps, therefore slickness can be improved.The average grain diameter of the rubber elastomer particle be more preferably 30nm or more, further it is excellent It is selected as 50nm or more, and more preferably 300nm or less, further preferably 280nm or less.

The number average bead diameter of rubber elastomer particle measures as follows.That is, this rubber elastomer particle is mixed into resin and shape At resin layer (a), when being dyed with the aqueous solution of ruthenium-oxide to its section, rubber elastomer particle is justified after being coloured with approaching Shape is observed.Therefore, thin slice is prepared by the section after so being dyed using ultramicrotome (microtome) etc., used Electron microscope observes the thin slice.Also, the rubber elastomer particle after random selection 100 dyeing, measurement are respective Partial size after, using its arithmetic mean of instantaneous value as number average bead diameter.

Wherein, for having the rubber elastomer particle of the rigid polymeric nitride layer based on alkyl methacrylate For number average bead diameter, using the number average bead diameter of rubber elastic polymers layer as the number average bead diameter of rubber elastomer particle.For example, making It is rigid polymeric nitride layer based on methyl methacrylate with outermost layer and to be wherein enclosed with acrylic rubber elasticity poly- In the case where the rubber elastomer particle for closing object, when being mixed into poly- (methyl) acrylate, should be with methyl methacrylate The rigid polymeric nitride layer of main body is confused with poly- (methyl) acrylate.Therefore, its section dyed with ruthenium-oxide, use electronics When microscope is observed, the rubber elastomer particle in the form of not including the particle of outermost state to be observed.Tool For body, the use of internal layer is acrylic rubber elastomeric polymer, outer layer is hard based on methyl methacrylate In the case where the rubber elastomer particle of the double-layer structure of polymer, the acrylic rubber elastomeric polymer portion of internal layer is contaminated Color, to be observed in the form of the particle of single layer structure, in addition, the use of innermost layer being based on methyl methacrylate The rigid polymer of body, middle layer are acrylic rubber elastomeric polymer, outermost layer is based on methyl methacrylate Rigid polymer three-decker rubber elastomer particle in the case where, the particle centre part of innermost layer is not colored, Only the acrylic rubber elastomeric polymer portion of middle layer is colored, to be observed in the form of the particle of double-layer structure It arrives.

The content of rubber elastomer particle is preferably 3 mass % or more and 60 mass % relative to the total amount of resin layer (a) Below, 5 mass % or more and 50 mass % or less are more preferably.When rubber elastomer particle is more than 60 mass %, resin layer (a) Change in size become larger, heat resistance be deteriorated.On the other hand, when rubber elastomer particle is less than 3 mass %, although resin layer (a) Heat resistance it is good, but the batching property when manufacturing this film is poor, and productivity declines sometimes.

It should be noted that in the present invention, using with the layer and other layers of multilayered structure for showing caoutchouc elasticity Particle as rubber elastomer particle when, by the quality for the part being made of the layer on the inside of the layer that shows caoutchouc elasticity and its Quality as rubber elastomer particle.Such as the outside of the layer in acrylic rubber elastomeric polymer has with metering system Rigid polymeric nitride layer based on acid alkyl ester has the rigid polymeric nitride layer based on alkyl methacrylate in inside Three-decker elastomer particle in the case where, by acrylic rubber elastomeric polymer layer and inside with methacrylic acid Quality of the total quality of rigid polymeric nitride layer based on Arrcostab as rubber elastomer particle.By this rubber elastomer When particle is dissolved in acetone, the acrylic rubber elastomeric polymer layer of middle layer and inside based on alkyl methacrylate The rigid polymeric nitride layer of body remains in the form of insoluble matter, thus the layer by showing caoutchouc elasticity and the layer on the inside of it are constituted Partial quality can easily be found out.

Poly- (methyl) acrylate contained in resin layer (a) is the polymer based on methacrylate, both may be used To be the homopolymer of methacrylate, be also possible to 50 mass % or more methacrylate and 50 mass % it is below this The copolymer of outer monomer.

On the basis of whole monomers, the preferred monomer composition of metha crylic resin is: methacrylate 50 ~100 mass %, alkyl acrylate are 0~50 mass %, the monomer other than these is 0~49 mass %, it is even more preferred that Methacrylate is 50~99.9 mass %, alkyl acrylate is 0.1~50 mass %, the monomer other than these be 0~ 49 mass %.

Methacrylate is preferably alkyl methacrylate.As alkyl methacrylate, methyl can be enumerated Methyl acrylate, ethyl methacrylate, butyl methacrylate, cyclohexyl methacrylate and methacrylic acid 2- ethyl hexyl Ester etc., the carbon atom number of the alkyl of alkyl methacrylate are usually 1~8, preferably 1~4.Wherein, particularly preferred methyl Methyl acrylate.

As alkyl acrylate, methyl acrylate, ethyl acrylate, butyl acrylate and acrylic acid 2- second can be enumerated Own ester of base etc., the carbon atom number of the alkyl of alkyl acrylate are usually 1~8, preferably 1~4.

Monomer other than methacrylate and alkyl acrylate can be carbon-in the molecule with 1 polymerism The monofunctional monomer of carbon double bond is also possible to the polyfunctional monomer of the carbon-to-carbon double bond with 2 or more polymerisms in the molecule, Preferably monofunctional monomer.As monofunctional monomer, the benzene second such as styrene, α-methylstyrene and vinyltoluene can be enumerated Alkene monomer；The alkenyl nitriles such as acrylonitrile and methacrylonitrile；Acrylic acid, methacrylic acid, maleic anhydride, itaconic anhydride etc. are no Saturated carboxylic acid；And N- methylmaleimido, n-ethylmaleimide, N- N-cyclohexylmaleimide, N- phenyl Malaysia N- substituted maleimide amine such as acid imide etc..In addition, as polyfunctional monomer, can enumerate ethylene glycol dimethacrylate, The how unsaturated carboxylate of the polyalcohols such as butanediol dimethylacrylate and trimethylolpropane trimethacrylate；Acrylic acid alkene The alkenyl ester of the unsaturated carboxylic acids such as propyl ester, allyl methacrylate and allyl cinnamate；Diallyl phthalate, The polyalkenes base ester of the polyacids such as diallyl maleate, triallylcyanurate and Triallyl isocyanurate；And Aromatic series polyalkenyl compound such as divinylbenzene etc..

Methacrylate, alkyl acrylate and the monomer other than these illustrated herein can use individually, Two or more can also be applied in combination.

Resin layer (a) can also contain lubrication prescription.Contain lubrication prescription by resin layer (a), thus it can be prevented that by this film roll Being closely wound when at web-like (volume I forms ま り), after thus winding in the state of container dimensions (severe appearance) improved.Lubrication prescription As long as having the function of that improving this film surface slickness both may be used.As the compound with this function, fatty acid can be enumerated Based compound, acrylic compounds, ester based compound etc..Preferably carbon atom number be 16~20 fatty acid series compound, Wherein preferred stearic acid based compound.

As stearic acid based compound, stearic acid can be enumerated；Methyl stearate, ethyl stearte, stearic acid list glycerol The stearates such as ester；Stearmide；The stearic acid such as odium stearate, calcium stearate, zinc stearate, lithium stearate, magnesium stearate gold Belong to salt；12- hydroxy stearic acid, 12- hydroxyl sodium stearate, 12- hydroxy stearic acid zinc, 12- hydroxy stearic acid calcium, 12- hydroxyl are hard The 12- hydroxy stearic acids and its metal salt etc. such as resin acid lithium, 12- hydroxy stearic acid magnesium.Preferably stearic acid.

The content of lubrication prescription in resin layer (a) is relative to the total of poly- (methyl) acrylate and rubber elastomer particle 100 mass parts are usually 0.15 below the mass, preferably 0.1 below the mass, further preferably 0.07 below the mass. When the content of lubrication prescription is excessive, lubrication prescription oozes out from resin layer (a) or makes the transparency decline of this film sometimes.

In addition, resin layer (a) can also be inhaled containing fluorescent whitening agent, dispersing agent, heat stabilizer, light stabilizer, ultraviolet light Receive the additives such as agent, infrared absorbent, antistatic agent and antioxidant.

Ultraviolet absorbing agent is the compound of absorbing wavelength 400nm ultraviolet light below.It, can be with as ultraviolet absorbing agent Enumerate benzophenone series ultraviolet absorbing agent, enumerate BTA system ultraviolet absorbing agent and acrylic ultraviolet absorbing agent etc..If Concrete example is enumerated, then has 2,2 '-di-2-ethylhexylphosphine oxides [4- (1,1,3,3- tetramethyl butyl) -6- (2H- benzotriazole -2- base) benzene Phenol], 2- (2 '--3 '-tert-butyls -5 of hydroxyl '-aminomethyl phenyl) -5- chlorobenzotriazole, (5- chlorobenzene is simultaneously by 2,4- di-t-butyl -6- Triazole -2- base) phenol, 2,2 '--4,4 '-dimethoxy-benzophenones and 2,2 ' of dihydroxy, 4,4 '-tetrahydroxybenzophenones etc.. Among these, preferably 2,2 '-di-2-ethylhexylphosphine oxides [4- (1,1,3,3- tetramethyl butyl) -6- (2H- benzotriazole -2- base) phenol]. The content of ultraviolet absorbing agent is preferably 10% or less, more preferably 5% in wavelength 370nm transmissivity below make this film It below, is more preferably to be selected in 3% range below.

Resin layer (a) is usually formed by the resin combination containing resin.As contain resin and rubber elastomer particle Resin combination manufacturing method, can enumerate: by the monomer as resin raw material in the presence of rubber elastomer particle It is polymerize, the method for thus obtaining being mixed with the composition of resin and rubber elastomer particle；And by rubber elastomer grain Son and resin carry out melting mixing, the method etc. for thus obtaining being mixed with the composition of resin and rubber elastomer particle.Lubrication prescription It can be mixed at any time with other additives.

[resin layer (b)]

Polycarbonate contained by preferred resin layer (b) can obtain by the following method: using interface polycondensation or The method that melt transesterification process etc. reacts dihydric phenol and carbonyl agent；Make polycarbonate prepolymer using solid phase ester-interchange method etc. The method that object is polymerize；Alternatively, the method etc. for polymerizeing cyclic carbonate compound using ring-opening polymerisation method.

As dihydric phenol, quinhydrones, resorcinol, 4 can be enumerated, 4 '-dihydroxybiphenyls, bis- (4- hydroxy phenyl) methane, Bis- { (4- hydroxyl -3,5- dimethyl) phenyl } methane, bis- (4- hydroxy phenyl) ethane of 1,1-, bis- (4- the hydroxy phenyl) -1- of 1,1- Bis- (4- hydroxy phenyl) propane (hereinafter sometimes referred to as bisphenol-A) of diphenylphosphino ethane, 2,2-, bis- { (4- hydroxy-3-methyl) benzene of 2,2- Base } propane, bis- { (4- hydroxyl -3,5- dimethyl) phenyl } propane of 2,2-, bis- { (4- hydroxyl -3,5- dibromo) phenyl } third of 2,2- Bis- { (3- isopropyl -4- hydroxyl) phenyl } propane of alkane, 2,2-, bis- { (4- hydroxyl -3- phenyl) phenyl } propane of 2,2-, 2,2- are bis- Bis- (4- the hydroxy phenyl) -3- methybutanes of (4- hydroxy phenyl) butane, 2,2-, bis- (4- the hydroxy phenyl) -3,3- dimethyl of 2,2- Bis- (4- the hydroxy phenyl) -2- methybutanes of butane, 2,4-, bis- (4- hydroxy phenyl) pentanes of 2,2-, 2,2- bis- (4- hydroxy phenyls) - Bis- (4- the hydroxy phenyl) -4- isopropyl cyclohexanes of 4- methylpentane, 1,1-bis(4-hydroxyphenyl)-cyclohexane, 1,1-, 1,1- are bis- (4- hydroxy phenyl) -3, bis- (4- hydroxy phenyl) fluorenes of 3,5- trimethyl-cyclohexanes, 9,9-, bis- { (4- hydroxy-3-methyl) benzene of 9,9- Base } fluorenes, α, α '-bis- (4- hydroxy phenyls) neighbour diisopropyl benzene, α, diisopropyl benzene, α between α '-bis- (4- hydroxy phenyls), α '-is bis- (4- hydroxy phenyl) bis- to diisopropyl benzene, 1,3- (4- hydroxy phenyl) -5,7- dimethyladamantanes, 4,4 '-dihydroxy hexichol Sulfone, 4,4 '-dihydroxy diphenyl sulfoxides, 4,4 '-dihydroxy diphenyl sulfides, 4,4 '-dihydroxydiphenyl ketone, 4,4 '-dihydroxy two Phenyl ether and 4,4 '-dihydroxydiphenyl esters etc..These may be used singly or in combination of two or more.

Preferred dihydric phenol is bisphenol-A, bis- { (4- hydroxy-3-methyl) phenyl } propane of 2,2-, bis- (the 4- hydroxy benzenes of 2,2- Base) butane, bis- (4- the hydroxy phenyl) -3- methybutanes of 2,2-, 2,2- bis- (4- hydroxy phenyl) -3,3- dimethylbutanes, 2,2- Bis- (4- hydroxy phenyl) -4- methylpentanes, bis- (4- the hydroxy phenyl) -3,3,5- trimethyl-cyclohexanes of 1,1- and bis- (the 4- hydroxyls of α, α ' - Base phenyl)-diisopropyl benzene.

More preferably be used alone bisphenol-A or share bis- (4- the hydroxy phenyl) -3,3,5- trimethyl-cyclohexanes of 1,1- with Between bis- { (4- hydroxy-3-methyl) phenyl } propane of bisphenol-A, 2,2- and α, α '-bis- (4- hydroxy phenyls) in diisopropyl benzene It is at least one kind of.

As carbonyl agent, the dihalo- first of the carbonic esters such as the carbonyl halides such as phosgene, diphenyl carbonate and dihydric phenol can be enumerated Haloformates such as acid esters etc..These may be used singly or in combination of two or more.

In addition, resin layer (b) can also be containing lubrication prescription, fluorescent whitening agent, dispersing agent, heat stabilizer, light stabilizer, ultraviolet The additives such as light absorbers, infrared absorbent, antistatic agent and antioxidant.The preferred type and content of these additives It is identical as the preferred embodiment in resin layer (a).

Resin layer (b) is usually formed by the resin combination containing resin.The resin combination can be by with any side Lubrication prescription and other additive of the method by resin, when necessary are obtained by mixing.

[phase difference film of the invention]

This film preferably has the optical characteristics indicated by formula (1).It is special that this film is more preferably the optics for having and being indicated by formula (2) Property phase difference film (hereinafter sometimes referred to as quarter wave plate) or there is the phase difference film of optical characteristics indicated by formula (3) (to have below When referred to as 1/2 wave plate), particularly preferably quarter wave plate.

70 < Re (590) < 320 (1)

70 < Re (590) < 160 (2)

200 < Re (590) < 320 (3)

Re (590) indicates to define phase difference value in the face of wavelength 590nm light by formula (I).

Re (590)=(n_x-n_y)×d(I)

n_xIndicate the refractive index of slow-axis direction in the face of film.n_y(in the face side orthogonal with slow axis of fast axis direction in expression face To) refractive index.D indicates thickness.

The phase difference of this film can be controlled by adjusting the stretching ratio of resin layer (b) and resin layer (a).

This film can have 2 layers or more resin layers (b), it is possible to have 2 layers or more resin layers (a), but at least 1 layer tree Rouge layer (a) is located at the outside of resin layer (b).In the case where the display surface of display device has this film, by making light exit side Face be resin layer (a), refractive index when from this film emergent light reduces, and light transmittance improves, therefore the brightness of display device Do not allow to tend to decrease.This film is preferably the phase difference that bilayer made of resin layer (b) and resin layer (a) are laminated one layer respectively is constituted Film (hereinafter sometimes referred to as phase difference film A) or it is sequentially laminated with three layers of resin layer (a), resin layer (b) and resin layer (a) The phase difference film (hereinafter sometimes referred to as phase difference film B) of composition, more preferably phase difference film B.One be bonded with other components When face is resin layer (a), tend to be excellent with the cementability of other components such as polarizing film.

It, can be in the resin existing for the viewing side in order to assign desired optical characteristics or other feature in this film There is surface-treated layer (coating layer) on the surface of layer (a).As surface-treated layer, can enumerate for preventing exterior light in table The anti-reflection layer of reflected image on face, the low antiglare layer of the flashing for preventing surface, to prevent Liquid Crystal Module in assembling procedure In galled spots for the purpose of hard conating, for improving surface waterproofing or antifouling stain-proofing layer etc..Furthermore it is possible to be resisted The processing of the functional surfaces such as electrostatic treatment.The method for forming surface-treated layer is not particularly limited, and well known method can be used.

Phase difference film B etc. has in this film of multilayer resin layer (a), can make rubber elastomer particle and above-mentioned additive Content in layers is different in layers.For example, if reduce rubber elastomer particle content, can be improved heat resistance, It is advantageous in terms of reducing change in size.In addition, if increase rubber elastomer particle content, improve impact resistance, Batching property, with the cementabilities of other components such as polarizing film in terms of be advantageous.

The thickness of this film is usually 3~100 μm, preferably 5~80 μm, more preferably 10~60 μm.

The thickness of resin layer (a) is usually 1~70 μm, preferably 2~40 μm.The thickness of resin layer (b) is usually 1~97 μm, preferably 2~30 μm.

The ratio of the thickness of resin layer (b) on the basis of total film thickness of this film is preferably 30~97%.Resin layer (b) Film thickness ratio shared in total film thickness of this film be preferably 40% or more, more preferably 55% or more.Also, preferably 95% or less, it is more preferably 90% or less.When the film thickness of resin layer (b) ratio shared in total film thickness of this film is very few, The elasticity modulus of this film declines, such as durability in the case where after elliptical polarization plate has the tendency that variation.On the other hand, When the film thickness of resin layer (b) ratio shared in total film thickness of this film is excessive, there is the insufficient trend of the surface hardness of film.This In the case that film has multilayer resin layer (b), these layers add up to above range, in addition, the thickness of each layer can phase It is same to can also be different.

The volume fraction of resin layer (b) on the basis of total volume of this film is preferably 30~97%.Resin layer (b) Volume ratio shared in total volume of this film is preferably 40% or more, more preferably 55% or more.Also, preferably 95% or less.When the volume of resin layer (b) ratio shared in total volume of this film is very few, under the elasticity modulus of this film Drop, for example, after elliptical polarization plate in the case where durability have the tendency that variation.On the other hand, the volume of resin layer (b) exists When shared ratio is excessive in total volume of this film, there is the insufficient trend of the surface hardness of film.This film has multilayer resin layer (b) in the case where, these layers add up to above range, in addition, the volume of each layer can be the same or different.

The ratio of the thickness of resin layer (a) on the basis of total film thickness of this film is preferably 3~70%.Resin layer (a) Film thickness ratio shared in total film thickness of this film be preferably 5% or more, more preferably 10% or more.Also, preferably 60% or less, it is more preferably 45% or less.In the case that this film has multilayer resin layer (a), these layers add up to above-mentioned model It encloses, in addition, the thickness of each layer can be the same or different.In the case that this film is phase difference film B, from inhibition phase difference From the perspective of the curling of film B, the thickness of preferably two layers of resin layer (a) is identical.

The volume fraction of resin layer (a) on the basis of total volume of this film is preferably 3~70%.Resin layer (a) Volume ratio shared in total volume of this film is preferably 5% or more.Also, preferably 60% or less, more preferably 45% or less.In the case that this film has multilayer resin layer (a), these layers add up to above range, in addition, each layer Volume can be the same or different.In the case that this film is phase difference film B, go out from the viewpoint for the curling for inhibiting phase difference film B Hair, the volume of preferably 2 layers resin layer (a) are identical.

This film preferably with 100 DEG C heat 10 minutes when the long direction さ of roller length direction (ロ ー Le in film) contraction Rate is that 2.0% mode below is formed.It is sudden and violent in the state of by this film and polarization plates fitting when shrinking percentage is greater than 2.0% When being exposed to high temperature, the contraction of polarization plates becomes larger, and the polarizing film contained in the polarization plates ruptures sometimes, therefore is undesirable. The shrinking percentage is preferably 1.5% or less, more preferably 1.0% or less.

This film is preferably set as the internal haze according to JIS K 7105-1981 " the optical characteristics test methods of plastics " measurement It is 5% or less.When internal mist is both greater than 5%, this film is assembled into white luminance decline when display device, picture is dimmed.It is internal Mist degree is more preferably 3% or less.

This film can be obtained by stretching to the film manufactured by the following method: will form resin layer (b) respectively After resin combination and the resin combination for forming resin layer (a) melt in an extruder, use supply head (feed block) The co-extrusion modling method that method or more material paths (multi manifold) method are laminated；Alternatively, will tree by extrusion moulding etc. After rouge layer (b) membranization, the resin combination for forming resin layer (a) is dissolved in the surface that the film is coated on after solvent as needed Method；Deng.The preferred manufacturing method of this film is to the method stretched through the obtained film of co-extrusion modling method.

In co-extrusion modling method, resin combination and roller after making melting or band (belt) is closely sealed carries out film molding.This When roller or radical, configuration or the material of band be not particularly limited, from improving the face precision of film surface, improve surface treatment property From the aspect of, the resin clip after preferably making melting contacts and passes through between 2 metallic rolls or with metallic roll and metal tape, by roller Or the method for the transferring surface shape of band.Alternatively, molten resin composition is clipped using metallic roll and flexible metallic roll, Keep the strain and reduction of molten resin composition and the two progress face contact and the method passed through when being reduced molding strong It is suitable in terms of the anisotropy of degree, the anisotropic film of heat-shrinkable.As metallic elastic roller, can lift as an example Out for example: the cylindrical metal system contacted with molten resin for having beaming roller and being configured in a manner of covering the beaming roller outer peripheral surface Film is sealed with the metallic elastic roller of the fluids temperature controlled such as water, oil between these beaming rollers and metal made membrane；In rubber The surface of rubber roller is wound with the metallic elastic roller of metal tape.

As drawing process, it can enumerate and be uniaxially stretched, is biaxial stretch-formed etc..As draw direction, can enumerate non-stretched The machine stream direction (MD) of film, the direction orthogonal with the machine stream direction (TD), with the direction of machine stream direction (MD) oblique etc..Twin shaft is drawn Stretch it is biaxial stretch-formed while can be along 2 draw directions while being stretched, be also possible to after being stretched along prescribed direction to Other directions stretch gradually biaxial stretch-formed.

Being uniaxially stretched can for example carry out as follows: 2 pairs or more of niproll for increasing the peripheral speed of outlet side is used, (machine stream direction: MD) carries out the two side ends and edge for stretching or utilizing chuck to hold unstretching film and machine stream direction along its length Orthogonal direction (TD) is extended.The two side ends of unstretching film are held preferably by chuck and are tilted along relative to machine stream direction The method that is stretched of direction.

The stretching ratio of stretch processing can be selected in a manner of obtaining desired phase difference.It is wherein preferably 30 ~500%, 50~300% are more preferably.When stretching ratio is lower than 30%, it is not easy to obtain desired phase difference, stretch again When rate is greater than 300%, film thickness is become too thin, and is easily broken or treatability declines.Stretching ratio is according to following formula:

Stretching ratio (%)=100 × { (length after stretching)-(length before stretching) }/(length before stretching) is asked Out.

Carry out it is biaxial stretch-formed in the case where, by stretching ratio M1 biggish among the stretching ratio in the direction MD and the direction TD and The M1/M2 that lesser stretching ratio M2 is found out is preferably 3 or more, more preferably 5 or more.When less than 3, it is difficult to obtain desired Phase difference.

Draft temperature is set as the temperature for showing the mobility of the degree of stretchable film entirety or more, preferably resin layer (b) in the range of -40 DEG C of glass transition temperature~+40 DEG C, the more preferably glass transition temperature of resin layer (b) - 25 DEG C~+25 DEG C in the range of, further preferably -15 DEG C of the glass transition temperature of resin layer (b)~+15 DEG C In the range of.

[elliptical polarization plate]

Elliptical polarization plate is obtained and this film to be fitted in a face of polarization plates.At this point, according to this film and polarization The face of the opposite side in the face of plate fitting is that the mode of resin layer (a) is laminated.Having in the display surface of display device has this In the case where the elliptical polarization plate (hereinafter sometimes referred to as this elliptical polarization plate) of film, by making the opposite of the face for being fitted with polarization plates The face of side is resin layer (a), and refractive index when by this elliptical polarization plate emergent light reduces, and light transmittance improves, therefore shows The brightness of device is not allowed to tend to decrease.In addition, if making the face resin layer (a) of the opposite side in the face for being fitted with polarization plates, aobvious Show that face has the surface hardness of the display device of the resin layer (a) sufficiently high, display surface tends to be not easily damaged.

Usually according to being about 45 ° between the axis of homology of polarization plates and the slow axis (optical axis) of this film between polarization plates and this film Mode is bonded.Usually 45 ± 20 ° of range.Alternatively, it is also possible to by making the optical axis of polarization plates and the optical axis one of this film It causes or orthogonal obtains the optical film functioned as optical compensation films.

As the polarization plates being bonded with this film, the successively polarization plates with protective film, polarizing film and protective film can be enumerated； Polarization plates with polarizing film and protective film；The polarization plates etc. being only made of polarizing film.Preferably there is polarizing film and protective film Polarization plates, preferably close this film in the polarizing film face paste of the polarization plates.

Fitting between this film and polarization plates is carried out usually using adhesive.Adhesive is preferably curability adhesive or pressure Quick property adhesive, more preferably curability adhesive, further preferably active energy ray-curable adhesive.

Be laminated with the elliptical polarization plate of phase difference film A and polarization plates layer constitute example in Fig. 1 with schematic cross-section It indicates.In addition, the example that the layer for being laminated with the elliptical polarization plate of phase difference film B and polarization plates is constituted is illustrated in Fig. 2 with section Figure indicates.

It is fitted in elliptical polarization plate 10 shown in FIG. 1: resin layer (a) 21 has been laminated in the single side of resin layer (b) 25 This film 20 and polarization plates 31 with polarizing film 30 and protective film 40.In the resin layer that the single side of resin layer (b) 25 is laminated (a) 21 sometimes referred to as the first resin layer (a).It is successively fitted in elliptical polarization plate 10 shown in Fig. 2: in resin layer (b) 25 Two-sided this film 20 for being laminated with the first resin layer (a) 21 and the second resin layer (a) 22 and have polarizing film 30 and protective film 40 polarization plates 31.

In above-mentioned figure, polarizing film 30 and this film 20 are bonded by gluing oxidant layer 51, polarizing film 30 and protective film 40 by Gluing oxidant layer 52 is bonded.Gluing oxidant layer is formed by adhesive, and preferred gluing oxidant layer is the solidification of curability adhesive Object, the more preferably solidfied material of active energy ray-curable adhesive.

[polarization plates]

The polarizing film 30 for constituting elliptical polarization plate 10 can be according to well known method by following process manufacture: to poly- The process that vinyl alcohol resin film is uniaxially stretched；Thus being dyed with dichroism pigment to polyvinyl alcohol resin film makes The process of dichroism pigment absorption；The polyvinyl alcohol resin film for being adsorbed with dichroism pigment is carried out using boric acid aqueous solution The process of processing；And the process washed after the processing using boric acid aqueous solution.The obtained polarizing film is above-mentioned The direction being uniaxially stretched have absorption axiss.

As polyvinyl alcohol resin, used after polyvinyl acetate system resin being saponified.As polyvinyl acetate Ester system resin can also enumerate vinyl acetate and can be with other than the polyvinyl acetate as leifa The copolymer etc. of its other monomer being copolymerized.As can with other monomers of vinyl acetate copolymerization, it can be cited for example that insatiable hunger With carboxylic acids, olefines, vinyl ethers, unsaturated sulfonic acid class, the acrylic amide with ammonium etc..

The saponification degree of polyvinyl alcohol resin is usually 85~100 moles of %, preferably 98 moles of % or more.The polyethylene Alcohol system resin can be modified, and can be used for example with the modified polyvinyl formal of aldehydes, polyvinyl acetal etc.. In addition, the degree of polymerization of polyvinyl alcohol resin is usually 1,000~10,000 or so, preferably 1,500~5,000 or so.

It will can be used as polarizing film former material film after this polyvinyl alcohol resin film.To by polyvinyl alcohol resin system The method of film is not particularly limited, and melting extrusion film can be used, solution casting applies method well known to film etc..To polyethenol series The film thickness of former material film is not particularly limited, and for example, 10~150 μm or so.

Polyvinyl alcohol resin film be uniaxially stretched can using dichroism pigment dyeing before, dyeing while or dye It is carried out after color.In the case where being uniaxially stretched after dyeing, this be uniaxially stretched can boric acid processing before or boric acid It is carried out in processing.Alternatively, it is also possible to be uniaxially stretched in above-mentioned multiple stages.Furthermore it is possible to be carried out together with support membrane Above-mentioned multiple processes.

Hot-rolling folder can also be can use by carrying out between the different roller spaced apart of peripheral speed by being uniaxially stretched It holds to carry out.In addition, this, which is uniaxially stretched, can be the dry type stretching stretched in an atmosphere, be also possible to using water, have Solvent equal solvent makes the wet tensile stretched in the state of polyvinyl alcohol resin membrane swelling.Stretching ratio is usually 3 ~8 times or so.

Polyvinyl alcohol resin film for example can be by containing dichroism pigment using the dyeing of dichroism pigment The method of polyvinyl alcohol resin film is impregnated in aqueous solution to carry out.As dichroism pigment, iodine, dichroism can be used to have engine dyeing Material.It should be noted that polyvinyl alcohol resin film preferably implements impregnation in water in advance before dyeing processing.

Use iodine as in the case where dichroism pigment, be typically employed in the aqueous solution containing iodine and potassium iodide impregnate it is poly- The method that vinyl alcohol resin film is dyed.The content of iodine in the aqueous solution is usually relative to every 100 mass parts water 0.01~1 mass parts or so.The content of potassium iodide is usually 0.5~20 mass parts or so relative to every 100 mass parts water.For The temperature of the aqueous solution of dyeing is usually 20~40 DEG C or so.In addition, dip time (dyeing time) in the aqueous solution is logical It is often 20~1,800 seconds or so.

On the other hand, use dichroic organic dye as in the case where dichroism pigment, be typically employed in containing water-soluble Property dichroic organic dye aqueous solution in the method that is dyed of dipping polyvinyl alcohol resin film.Two in the aqueous solution The content of color organic dyestuff is usually 1 × 10 relative to every 100 mass parts water^-4~10 mass parts or so, preferably 1 × 10^-3 ~1 mass parts or so.The aqueous solution can contain the inorganic salts such as sodium sulphate as dyeing assistant.Dichroic dye for dyeing The temperature of aqueous solution is usually 20~80 DEG C or so.In addition, dip time (dyeing time) in the aqueous solution is usually 10 ~1,800 seconds or so.

It can be existed by the polyvinyl alcohol resin film after dyeing using the boric acid processing after the dyeing of dichroism pigment The method impregnated in the aqueous solution of boronic acid containing carries out.The amount of boric acid in the aqueous solution of boronic acid containing is relative to every 100 mass parts Water is usually 2~15 mass parts or so, preferably 5~12 mass parts.Use iodine as in the case where dichroism pigment, the boracic The aqueous solution of acid preferably comprises potassium iodide.The amount of potassium iodide in the aqueous solution of boronic acid containing is usual relative to every 100 mass parts water For 0.1~15 mass parts or so, preferably 5~12 mass parts.Dip time in the aqueous solution of boronic acid containing is usually 60~ 1,200 seconds or so, preferably 150~600 seconds, further preferably 200~400 seconds.The temperature of the aqueous solution of boronic acid containing is usual It is 50 DEG C or more, preferably 50~85 DEG C, further preferably 60~80 DEG C.

By carrying out washing process to boric acid treated polyvinyl alcohol resin film.Washing process is for example by by boric acid Treated polyvinyl alcohol resin film immersion is carried out in water.The temperature of water in washing process is usually 5~40 DEG C or so. In addition, dip time is usually 1~120 second or so.

Implement to be dried after washing, polarizing film can be obtained.Air drier can be used in drying process, far infrared adds Hot device carries out.The temperature of drying process is usually 30~100 DEG C or so, preferably 50~80 DEG C.The time of drying process is usual It is 60~600 seconds or so, preferably 120~600 seconds.

The moisture content of polarizing film is reduced to practical level by being dried.The moisture content be usually 5~20 mass %, Preferably 8~15 mass %.When moisture content is less than 5 mass %, polarizing coating loses flexibility, and polarizing film generates sometimes after the drying Damage or rupture.On the other hand, when moisture content is greater than 20 mass %, there is the insufficient trend of the thermal stability of polarizing film.

The thickness that thus obtained gas absorption quantity has the polarizing film of dichroism pigment is usually 2~40 μm.

[protective film]

The driving method for the liquid crystal cells that protective film 40 can have according to the display device uses any protective film.Example Such as, the liquid crystal cells for transverse electric field (IPS) mode are, it is preferable to use having 30nm or less, preferably 20nm or less, being more preferably The protective film of phase difference value functioned as low phase difference film in the face below 10nm.On the other hand, for vertical orientation (VA) protective film functioned as phase difference film can be used in the liquid crystal cells of mode.

It, can be by cellulose-based resin, olefin-based resin, polyethylene terephthalate system tree for protective film 40 The membranizations such as rouge, polycarbonate-based resin, acrylic resin and constitute protective film 40.

These resin forming film-like can be regard as protective film after implementing stretch processing.It can be by along MD at this point, stretching What (direction of transfer) or TD (direction orthogonal with direction of transfer in face) were stretched is uniaxially stretched, along the two sides of MD and TD To the biaxial stretch-formed, edge stretched neither any method such as oblique extension that the direction that MD is also not TD is stretched into Row.By implementing the stretched operation, the protective film of available high mechanical strength.

Cellulose-based resin refers to be obtained from raw celluloses such as velveteen, wood pulps (broad leaf tree paper pulp, coniferous tree paper pulp) To cellulose hydroxyl in hydrogen atom part or all by the acyl group of acetyl group, propiono and/or bytyry etc Cellulose organic ester or cellulose mixed organic acid ester after substitution.It can be cited for example that wrapping cellulose-containing acetic acid esters, third Acid esters, butyrate, these mixed ester etc. film.Wherein, preferably tri cellulose acetate membrane, cellulose diacetate film, acetic acid third Acid cellulose film, cellulose acetate-butyrate film etc..

Olefin-based resin refers to the chain olefin monomer or drop using catalyst for polymerization to such as ethylene, propylene etc Resin obtained from the cyclic olefin monomers of bornylene, other cyclopentadiene derivants etc are polymerize.

As the olefin-based resin obtained by chain olefin monomer, polyethylene-based resin, polypropylene-based resin can be enumerated. Wherein, preferably as the polypropylene-based resin of Noblen.In addition, it is also preferred that based on propylene, usually with 1~20 matter It measures the ratio of %, preferably have the polypropylene-based copolymerization for the comonomer that can be copolymerized with propylene with the ratio copolymerization of 3~10 mass % Resin.

As the comonomer that can be copolymerized with propylene, preferably ethylene, 1- butylene or 1- hexene.Wherein, for the transparency, Stretch process is relatively excellent, it is preferable to use ethylene, has ethylene with the ratio copolymerization of 1~20 mass %, especially 3~10 mass % Polypropylene-based copolymer resins be one of preferred.By making the 1 mass % of copolymerization ratios or more of ethylene, raising is thus shown The transparency, the effect of stretch process.On the other hand, when which is greater than 20 mass %, the fusing point decline of resin, to protective film Or heat resistance required by phase difference film is damaged sometimes.

Polypropylene-based resin can be readily available commercially available product, can be enumerated for example with trade name respectively: by Prime " Prime Polypro (registered trademark) " of Polymer sale is sold by Japan Polypropylene Corporation " NOVATEC (registered trademark) " and " WINTEC (registered trademark) ", by Sumitomo Chemical Co sell " Sumitomo Noblen (registered trademark) ", by Sun Allomer " Sun Allomer (registered trademark) " sold etc..

The olefin-based resin for making cyclic olefin monomers be polymerized generally also is referred to as annular ethylene series resin, ester ring type alkene Hydrocarbon system resin or norbornene resin.Referred to herein as annular ethylene series resin.

As annular ethylene series resin, it can be cited for example that: diels-Alder will be passed through by cyclopentadiene and olefines Norbornene or derivatives thereof obtained from (Diels-Alder) reaction carries out ring opening metathesis polymerization as monomer, by with Afterwards plus hydrogen obtained from resin；Diels-A Er will be passed through by dicyclopentadiene and olefines or (methyl) esters of acrylic acid Tetracyclododecane obtained from moral reaction or derivatives thereof carries out ring opening metathesis polymerization as monomer, is added by subsequent Resin obtained from hydrogen；Use 2 in norbornene, tetracyclododecen, their derivative species or other cyclic olefin monomers Kind or more be carried out similarly ring-opening methathesis copolymerization, the resin as obtained from subsequent plus hydrogen；Make selected from above-mentioned norbornene, At least one kind of cyclic olefin in tetracyclododecen and their derivatives and aliphatic or aromatic compound with vinyl Carry out resin obtained from addition copolymerization etc..

Annular ethylene series resin can also be readily available commercially available product, can be enumerated for example with trade name by Germany respectively " TOPAS " (ト ー パ that TOPAS ADVANCED POLYMERS GmbH is produced, sold in Japan by Polyplastics company ス) (registered trademark), " Arton " (registered trademark) that is manufactured and sold by JSR company, Nippon Zeon Co., Ltd. manufacture and sell " ZEONOR " (registered trademark) and " ZEONEX (registered trademark) ", " APEL " for being manufactured and being sold by Mitsui Chemicals, Inc (registered trademark) etc..

It is filmed and membranization by by above-mentioned chain olefin system resin or annular ethylene series resin, protection can be formed Film 40.The method of membranization is not particularly limited, it is preferred to use melting extrusion is film-made method.

Olefin-based resin film can be respectively with quotient if capable of being also readily available commercially available product, such as polypropylene-based resin film The name of an article enumerates " the FILMAX CPP film " sold by FILMAX company, " the SUNTOX " (registrar sold by Suntox company Mark), " Tohcello " (registered trademark) sold by Tohcello the company, " TOYOBO sold by Toyo Boseki K.K PYLEN (registered trademark) film ", You Dongli film process " TORAYFAN (registered trademark) " etc. of Co., Ltd.'s sale.In addition, cyclic annular If olefin-based resin film can respectively with trade name enumerate by Nippon Zeon Co., Ltd. sale " ZEONOR film " (registered trademark), " Arton (registered trademark) film " etc. sold by JSR company.

Polyethylene terephthalate system resin refers to 80 moles of % or more of repetitive unit by ethylene terephthalate The resin of composition can also contain the structural unit from other copolymer compositions.As other copolymer compositions, isophthalic can be enumerated Dioctyl phthalate, 4,4 '-dicarboxylate biphenyls, 4,4 '-benzophenonedicarboxylic acids, bis- (4- carboxyl phenyl) ethane, adipic acid, decanedioic acid, The dicarboxylic acid component of 5-sodium sulfo isophthalate and 1,4- dicarboxyl butylcyclohexane etc；Propylene glycol, butanediol, neopentyl glycol, The glycol of diethylene glycol, cyclohexanediol, the ethylene oxide adduct of bisphenol-A, polyethylene glycol, polypropylene glycol and polytetramethylene glycol etc Ingredient.Two or more can be applied in combination in these dicarboxylic acid components, diol component as needed.In addition, also can be with above-mentioned dicarboxyl Sour component, diol component share P-hydroxybenzoic acid, to the hydroxycarboxylic acid of beta-hydroxy ethoxybenzoic acid etc together.As it Its copolymer composition, also can be used just the dicarboxylic acid component for having a small amount of amido bond, ammonia ester bond, ehter bond, carbonic acid ester bond etc. and/or Diol component.

Polycarbonate-based resin and acrylic resin can be to be gathered with what is illustrated as resin used in this film 20 Carbonic ester and the same substance of poly- (methyl) acrylate.Also the layer of polycarbonate-based resin and acrylic resin can be used Folded film is as protective film 40, at this point, acrylic resin preferably comprises rubber bullet in the same manner as the resin layer (a) for constituting this film 20 Property body particle.

For protective film 40, optical functional film or coating optical functional layer can be laminated on its surface.As this Optical functional film and optical functional layer, it can be cited for example that adhesive layer, conductive layer etc..

If it is form shown in FIG. 1, then 25 side of resin layer (b) of this film 20 is fitted in into polarizing film 30, in polarizing film The face paste of the opposite side in the face of 30 fitting this film 20 closes protective film 40, and polarization plates 10 are made.If it is form shown in Fig. 2, 22 side of the second resin layer (a) of this film is then fitted in into polarizing film 30, the opposite side in the face of fitting this film 20 of polarizing film 30 Face paste close protective film 40, polarization plates 10 are made.In Fig. 1 and Fig. 2, respectively, this film 20 fits in partially via gluing oxidant layer 51 Shake piece 30, in addition, protective film 40 fits in polarizing film 30 via gluing oxidant layer 52.In being bonded of this film 20 and polarizing film 30, only Glue is coated in 25 side of resin layer (b) of this film 20 or 22 side of the second resin layer (a) and any place of the bonding plane of polarizing film 30 The two is bonded after stick, in being bonded of protective film 40 and polarizing film 30, as long as in the viscous of protective film 40 and polarizing film 30 The two is bonded after any place's coating binder of junction.

[bonding]

In the polarizing film 30 or protective film that 22 pairs of polarization plates of resin layer (b) 25 or the second resin layer (a) of this film 20 have In being bonded of the polarizing film 30 that 40 fitting and polarization plates have and protective film 40, adhesive is used as described above.It is being bonded Before, preferably in advance to each film binding face at least one of implement Corona discharge Treatment, plasma irradiating processing, electronics Radiation exposure processing, the processing of other surface activations.

Bonding force can be shown to each component by being used to form Fig. 1 and the adhesive shown in Fig. 2 for connecing oxidant layer 51,52 Arbitrarily selection uses in adhesive.Typically, it can enumerate: even if water system adhesive, glue as one of curability adhesive Stick ingredient be dissolved in water or adhesive component made to be scattered in water after water system adhesive；And containing because of active energy beam It irradiates and the active energy ray-curable adhesive of cured ingredient., it is preferable to use active energy from the viewpoint of productivity Measure ray-curable adhesive.

As preferred water system adhesive, it can enumerate and contain polyvinyl alcohol resin or carbamate resins as master Want the composition of ingredient.

Use polyvinyl alcohol resin as in the case where water system adhesive main component, the polyvinyl alcohol resin is in portion Divide other than the pure and mild fully saponified polyvinyl alcohol of saponified polyvinyl and can also be that carboxy-modified polyvinyl alcohol, levulinic ketone group are modified poly- The modified polyvinyl alcohol resin of vinyl alcohol, methylol-modified polyvinyl alcohol, amino modified polyvinyl alcohol etc.Using poly- In the case that vinyl alcohol resin is as adhesive component, adhesive system mostly in the form of polyvinyl alcohol resin aqueous solution It is standby.The concentration of polyvinyl alcohol resin in adhesive aqueous solution is usually 1~10 mass parts left side relative to 100 mass parts of water Right, preferably 1~5 mass parts.

To improve cementability, second two preferably is added in polyvinyl alcohol resin water system adhesive as main component The curability compositions such as aldehyde, water-soluble epoxy resin or crosslinking agent.As water-soluble epoxy resin, can enumerate for example: by two The polyalkylene polyamine of ethylenetriamine, trien etc is gathered with the reacting for dicarboxylic acids of adipic acid etc Amide polyamine, polyamide polyamine epoxy resin obtained from reacting epichlorohydrin with obtained polyamide polyamine.Make For the commercially available product of the polyamide polyamine epoxy resin, there is " the Sumirez for example sold by Taoka Chemical Industries Co. Ltd. What (registered trademark) Resin 650 " was sold with " Sumirez (registered trademark) Resin 675 ", by Nippon PMC K. K. " WS-525 " etc., can be properly used them.The additive amount of these curability compositions or crosslinking agent is relative to polyethenol series tree 100 mass parts of rouge are usually 1~100 mass parts, preferably 1~50 mass parts.When its additive amount is few, the effect of cementability is improved Reduce, on the other hand, when additive amount is more, gluing oxidant layer tends to tender.

Carbamate resins are used as in the case where the main component of water system adhesive, as adhesive group appropriate The example for closing object can enumerate mixing of the Polyester from aggressiveness type carbamate resins and the compound with glycidoxy Object.Signified Polyester refers in the carbamate resins with polyester backbone from aggressiveness type carbamate resins herein Carbamate resins after importing a small amount of ionic ingredient (hydrophilic component).It can not used from aggressiveness type carbamate resins Emulsifier and directly emulsification forms lotion in water, therefore be suitable as water-based adhesive.According to such as Japanese Unexamined Patent Publication 2005- No. 70139 bulletins, Japanese Unexamined Patent Publication 2005-70140 bulletin, Japanese Unexamined Patent Publication 2005-181817 bulletin etc., by Polyester from poly- Figure carbamate resins are well known for bonding between polarizing coating and protective film.

On the other hand, use activation energy ray-curable adhesive in the case where, constitute the adhesive because of activity The irradiation of energy-ray and cured ingredient (hereinafter sometimes referred to simply as " curability composition ") is epoxide, oxetanes Compound, acrylic compounds etc..Use the change of the cationically polymerizable of epoxide, oxetane compound etc In the case where closing object, mixed cationic polymerization initiators.In addition, using free-radical polymerisedization of acrylic compounds etc Mixed radical polymerization initiator in the case where conjunction object.Wherein, preferably using epoxide as the glue of one of curability composition Stick, particularly preferably using saturation hydrocarbon ring on Direct Bonding have the cycloaliphatic epoxy of epoxy group as curability composition it One adhesive.In addition, it is also effective for sharing oxetane compound to it.

Epoxide can also be readily available commercially available product, for example have with respective trade name by Mitsubishi chemical Co., Ltd Sale " JER (registered trademark) epoxy resin " series, by Dainippon Ink Chemicals sale " EPICLON (registered trademark) " series, By " EPOTOHTO (registered trademark) " series of Nippon Steel & Sumitomo Metal Corporation's sale, by Asahi Denka Co., Ltd.'s sale " ADEKA (registered trademark) Resin " series, by Nagase Chemtex company sale " Denacol (registered trademark) " series, It is sold by " D.E.R. (registered trademark) epoxy resin " series of Dow Chemical's sale, by Nissan Chemical Ind Ltd " TEPIC (registered trademark) " etc..

Direct Bonding has the cycloaliphatic epoxy of epoxy group that can also be readily available commercially available product in saturation hydrocarbon ring, For example have with trade name respectively by Daicel chemical industry Co., Ltd. sale " CELLOXIDE (registered trademark) " series and " CYCLOMER (registered trademark) " series, " Cyracure (the registered trademark) " series sold by Dow Chemical etc..

Oxetane compound can also be readily available commercially available product, for example have with trade name synthesize strain by East Asia respectively " the ETERNACOLL that " ARONE OXETANE (registered trademark) " of formula commercial firm sale is serial, is sold by Ube Industries, Ltd (registered trademark) " series etc..

Cationic polymerization initiators can also be readily available commercially available product.For example have with trade name respectively by Japanese chemical drug strain " Cyracure (registered trademark) " that " KAYACURE (registered trademark) " of formula commercial firm sale is serial, is sold by Dow Chemical Series, the photoacid generator photoacid generator " CPI " sold by Sanapro company series, sold by green Chemical Co., Ltd. " TAZ ", " BBI " and " DTS ", " ADEKA (registered trademark) OPTMER " sold by ADEKA company series, by Rhodia company " RHODORSIL (registered trademark) " series etc. of sale.

Active energy ray-curable adhesive can according to need containing photosensitizer.By using photosensitizer, reactivity It improves, can be further improved mechanical strength, the adhesive strength of solidified material layer.As photosensitizer, it can be cited for example that carbonylation Close object, organosulfur compound, persulfide, redox based compound, azo-compound and diazonium compound, anthracene system chemical combination Object, halide, photo-reduction pigment etc..

In addition, mixture various can add in the range of not damaging its cementability in active energy ray-curable adhesive Add agent.As additive, it can be cited for example that ion capturing agent, antioxidant, chain-transferring agent, tackifier, thermoplastic resin, filling out Fill agent, flowing regulator, plasticizer, defoaming agent etc..Furthermore, it is possible in the range of not damaging its cementability containing with sun from Son polymerize different reaction mechanisms and carries out cured curability composition.

Active energy ray-curable adhesive described above is applied to the binding face or polarizing film 30 of this film 20 Binding face irradiates active energy beam to it and solidifies, formed 30 He of polarizing film by the coating layer by after the fitting of two films The gluing oxidant layer 51 that this film 20 engages.In addition, the binding face of polarizing film 30 or the binding face of protective film 40 are coated on, by this After two films are bonded by coating layer, active energy beam is irradiated to it and is solidified, formation engages polarizing film 30 and protective film 40 Gluing oxidant layer 52.The adhesive for being used to form the adhesive of gluing oxidant layer 51 and being used to form gluing oxidant layer 52 can be phase It is also possible to different compositions with composition, but for making the irradiation of the cured active energy beam of the two preferably while carrying out.

Active energy beam used in the solidification of active energy ray-curable adhesive can be for example wavelength be 1~ The visible light etc. that ultraviolet light that the X-ray of 10nm, wavelength are 10~400nm, wavelength are 400~800nm.Wherein, from Yi Liyong From the aspect of property and the easy preparative of active energy ray-curable adhesive, stability and curing performance, it is preferable to use Ultraviolet light.Low pressure mercury lamp, the middle pressure mercury for example below wavelength 400nm with the distribution that shines can be used in the light source of ultraviolet light Lamp, high-pressure sodium lamp, ultrahigh pressure mercury lamp, chemistry, black light lamp, microwave-excited mercury lamp, metal halide lamp, electrodeless lamp etc..

The thickness of the gluing oxidant layer obtained using active energy ray-curable adhesive is usually 0.1~50 μm or so, But particularly preferably it is in 0.2~10 μm of range.

[purposes of elliptical polarization plate]

The display surface of liquid crystal cells can be fitted in Fig. 1 and the elliptical polarization plate 10 shown in Fig. 2 for being configured to typical case Side (viewing side) and the liquid crystal display panel for liquid crystal display device is made.Since the light being emitted from the light source of liquid crystal display device is saturating It crosses elliptical polarization plate and is emitted to viewing side, thus even if viewer observes the display device through polarized sunglasses, it can also be with Display picture is observed well.Such as by the outside of the protective film 40 having in elliptical polarization plate 10, i.e. with polarizing coating 30 Pressure-sensitive adhesive oxidant layer is arranged in the opposite side of binding face, it is possible thereby to easily be bonded with liquid crystal cells.The pressure-sensitive adhesive Layer generally formed by acrylic pressure sensitive adhesive, the acrylic pressure sensitive adhesive using acrylate as mainly at Divide, have the acrylic resin of the acrylic monomer containing functional group as pressure-sensitive adhesive ingredient using copolymerization.It needs to illustrate , the liquid crystal cells for constituting liquid crystal display panel can be the various liquid crystal cells used in the field.

[embodiment]

Embodiment described below is further elaborated with the present invention.In example, as long as indicating % and part of content and usage amount Not having special declaration is exactly quality criteria.

Examples 1 to 4

[rubber elastomer particle]

Rubber elastomer particle is using innermost layer by methyl methacrylate and a small amount of allyl methacrylate to polymerize Made of rigid polymer is constituted, middle layer be by that will make butyl acrylate, styrene and a small amount of metering system as main component Soft rubber elastomer that allyl propionate is polymerized constitutes, outermost layer is by by methyl methacrylate and a small amount of ethyl acrylate The rubber elastomer particle A for the three-decker that the rigid polymer being polymerized is constituted.In the extremely conduct of rubber elastomer particle A Number average bead diameter until the rubber elastomer of interbed is 240nm, in addition, total quality of innermost layer and middle layer is that particle is whole 70%.

[resin combination (a) for being used to form resin layer (a)]

By the methyl methacrylate system resin (" SUMIPEX (registered trademark) MH ") of Sumitomo Chemical Co and rubber Glue elastomer particle A is obtained by mixing resin combination (a).At this point, according to make rubber elastomer particle A relative to resin combination The content of object (a) total amount is that 30 mass % are mixed.It should be noted that the quality of rubber elastomer particle A is rubber bullet Total quality of innermost layer and middle layer in property body particle A.

[resin combination (b) for being used to form resin layer (b)]

Resin combination (b) uses " CALIBRE (registrar of Sumika Styron Polycarbonate corporation Mark) 301-15 ".

Respectively, resin combination (a) is put intoSingle screw extrusion machine melted, by resin combination (b) it puts intoSingle screw extrusion machine melted, supplied with distribution needle (distribution ピ Application) to more material paths using 2 kinds 3 layers It gives, melting stacking integration is carried out, via 260 DEG C of set temperature of T-type die extrusion.By the way that obtained membranoid substance is sandwiched in It is formed between a pair of of metal roll of smooth surface, is made and is sequentially laminated with the first resin layer (a), resin layer (b) and the Film A~D (non-stretched) of two resin layers (a).At this point, by the extrusion output for adjusting extruder, to integral thickness, the first resin layer (a) thickness of thickness, resin layer (b) and the thickness of the second resin layer (a) are adjusted.Film A obtained in Examples 1 to 4 The respective thickness of~D is shown in table 1.In addition, manufacturing the film E (comparative example being only made of resin combination (b) by the same method 1) the film F (comparative example 2) and being only made of resin combination (a).

[table 1]

[embodiment 5]

Horizontal stretching is carried out to film A using stenter and obtains phase difference film A.Specifically, the pre-heat treatment is carried out to film A Afterwards, it is carried out later to cross by stretching the horizontal stretching that progress is 2.8 times relative to the multiplying power of the film of unstretched state between chuck The heat fixation processing that film after stretching is heat-treated.The temperature condition of each process is shown in table 2.

[embodiment 6~8, comparative example 3,4]

Film A is set as film B~F, the temperature condition of each process is set as temperature shown in table 2, in addition to this with embodiment 5 Phase difference film B~F is got similarly.

[table 2]

Following physical property are measured to phase difference film A~F.As a result it is shown in table 3.

[total light transmittance]

It uses " HAZEMETER HM-150 ", measures transmissivity using light source D65, optical condition JIS K 7361.

[(590) phase difference value Re in face]

The measuring difference of phases device " KOBRA-WR " of machine Co. Ltd. system is measured using prince, is measured in wavelength 590nm Face in phase difference value Re (590).

[tensile modulus of elasticity measurement]

Elasticity modulus is measured to draw direction (TD) and the direction orthogonal with the direction (MD) in the following manner.Manufacture width Strip (short volume shape) resin sample of 2.5cm, length 15cm use Autograph (society, Shimadzu Seisakusho Ltd. system, AG-I) measurement 85 DEG C elongation and stress of the strip resin sample in length direction, calculate elasticity modulus.Experimental condition is set to distance between chuck It is 10mm/ minutes for 5cm, tensile speed.

[refractive index]

It is measured under conditions of 23 DEG C of temperature in 590nm wavelength using Abbe refractometer (" DR-M2 " of Atago corporation) The refractive index at place.

[intrinsic birefringent]

Using the refractive index obtained in detecting refractive index, the measuring difference of phases of machine Co. Ltd. system is measured using prince Device " KOBRA-WR " is calculated.

[table 3]

The refractive index and total light transmittance of the resin layer (a) that phase difference film A~D has with resin layer (a) monomer The refractive index and total light transmittance of phase difference film F made of form is same.In addition, the resin layer that phase difference film A~D has (b) refractive index, intrinsic birefringent and total light transmittance in the form of resin layer (b) monomer made of phase difference film E Refractive index, intrinsic birefringent and total light transmittance are same.

It is found that the total light transmittance of phase difference film A~D is high, it is not easy to make the brightness of display device to decline.In addition, phase 85 DEG C of elasticity modulus of poor film A~D are sufficiently high, therefore for example when elliptical polarization plate is made using these films, elliptical polarization plate Durability improve.

Industrial availability

According to the present invention it is possible to obtain the phase difference film for being difficult to make the brightness of display device to decline.

Symbol description

10 elliptical polarization plates

20 films

21 first resin layers (a)

22 second resin layers (a)

25 resin layers (b)

30 polarizing films

31 polarization plates

40 protective films

51,52 gluing oxidant layer

Claims (12)

1. a kind of phase difference film, it is laminated in the phase difference film:

The resin layer a that refractive index is 1.50 or less, total light transmittance is 80% or more；With

Refractive index is 1.55 or more, it is intrinsic it is birefringent be 0.07 or more, the resin layer b that total light transmittance is 80% or more,

At least one layer of resin layer a is located at the outside of resin layer b.

2. phase difference film as described in claim 1, wherein

Resin layer b is Polycarbonate Layer.

3. phase difference film as claimed in claim 1 or 2, wherein

Resin layer a is poly- (methyl) acrylate layer.

4. phase difference film as claimed in claim 1 or 2 has the optical characteristics indicated by following formula (1),

70 < Re (590) < 320 (1),

Re (590) is indicated for phase difference value in the face of wavelength 590nm light.

5. phase difference film as claimed in claim 1 or 2, wherein

The volume fraction of resin layer b is 30%~95%.

6. phase difference film as claimed in claim 1 or 2, wherein

Resin layer a contains poly- (methyl) acrylate and rubber elastomer particle.

7. phase difference film as claimed in claim 6, wherein

The number average bead diameter of rubber elastomer particle is 10nm~350nm.

8. phase difference film as claimed in claim 6, wherein

The content of rubber elastomer particle in resin layer a is 3 mass % or more and 60 mass % or less.

9. phase difference film as claimed in claim 1 or 2, wherein being sequentially laminated with resin layer a, resin layer b and resin layer a.

10. phase difference film as claimed in claim 1 or 2 is the film after resin layer a and resin layer b is stretched.

11. a kind of elliptical polarization plate, wherein being sequentially laminated with described in any item phase difference films, the adhesive of claim 1~7 Layer and polarizing film.

12. elliptical polarization plate as claimed in claim 11, wherein

Gluing oxidant layer is the solidfied material of active energy ray-curable adhesive.