CN1967294A - Stacked retardation plate, stacked polarizing plate including the same and image display - Google Patents

Abstract

The present invention provides a stacked phase shift sheet that, when used in a liquid crystal display, exhibits excellent viewing angle characteristics and enables realizing a thickness reduction. The stacked phase shift sheet is formed by stacking together an optically anisotropic layer of polymer (A) exhibiting an in-plane phase shift of 20 to 300 nm and a ratio between thickness-direction phase shift and in-plane phase shift of 1.0 or greater and an optically anisotropic layer of non-liquid-crystal polymer such as a polyimide (B) exhibiting an in-plane phase shift of 3 nm or greater and a ratio between thickness-direction phase shift and in-plane phase shift of 1.0 or greater. This stacked phase shift sheet exhibits such excellent optical characteristics that the in-plane phase shift (Re) is 10 nm or greater while the difference between thickness-direction phase shift and in-plane phase shift is 50 nm or greater.

Description

The lamination retardation plate, use the lamination polaroid and the image display of this lamination retardation plate

The application is that international filing date is February 18, international application no in 2003 the dividing an application for the patented claim of " lamination retardation plate, use the lamination polaroid and the image display of this lamination retardation plate " that be PCT/JP03/01682 (Chinese application number is 03804185.5), denomination of invention.

Technical field

The present invention relates to the lamination retardation plate, use the lamination polaroid and the various image display of this lamination retardation plate.

Background technology

Usually, in order to realize good display level on all directions, various image displays need have the retardation plate of control refractive index, and wait according to the display packing of LCD and to select type.Should particularly point out VA (homeotropic alignment) type or OCB (optical compensation curved) type LCD and need provide on three axial (X-axis, Y-axis and Z axles) that ' refractive index of nx＞ny＞nz ' promptly shows the retardation plate of optical negative biaxiality (optically negative biaxiality).Satisfy that ' well known examples of the retardation plate of nx＞ny＞nz ' comprises the lamination retardation plate that forms by two stretching polymer films of lamination (the free end uniaxial tension of described thin polymer film to be to provide ' nx＞ny=nz ', and wherein the slow axis in two stretching polymer film planes intersects mutually with the right angle); And by making thin polymer film stand stenter cross directional stretch or biaxial stretch-formed refractive index ' the individual layer retardation plate of nx＞ny＞nz ' of controlling.

Summary of the invention

Although the lamination retardation plate has the advantage of the wide region length of delay that the combination by oriented film obtains, it also has film laminating further to increase the shortcoming of film thickness.On the other hand, ' optical property of nx＞ny＞nz ' but favourable, shortcoming are that it is thick and the length of delay of close limit is provided although the individual layer retardation plate that has only one deck is because of it has.Therefore, the scope of length of delay must enlarge by the additional retardation films of lamination.In addition, when this individual layer retardation plate be used to obtain the thickness direction retardation value obviously greater than face in during the length of delay of length of delay, as the situation of lamination retardation plate, the further additional retardation films of lamination, this will further increase thickness.

Use non-liquid crystal polymer (for example polyimide) to produce thin and satisfy that ' method of the individual layer retardation films of nx＞ny＞nz ' is open (for example consulting JP 2000-190385A) also.But when the length of delay of thickness direction is set as when big, because not clear, this individual layer retardation films of being made up of polyimide has color, and this can reduce display quality.

Therefore, target of the present invention provides the laminated-type retardation plate that has good viewing angle characteristic and show high-contrast when being used for LCD, and it has the big thickness retardation and the thickness of reduction, prevents painted simultaneously.

In order to realize above-mentioned target, the invention provides the lamination retardation plate that comprises at least two optical anisotropic layers, it comprises the optical anisotropic layer (A) made by polymkeric substance and at least by being selected from polyamide, polyimide, polyester, polyaryletherketone, polyetherketone, the optical anisotropic layer (B) that at least a non-liquid crystal polymer in polyamidoimide and the polyester-imide is made, wherein postponing (Re) in the face of being represented by equation is 10 nanometers or bigger, and the difference (Rth-Re) between the delay (Re) is 50 nanometers or bigger in the thickness direction retardation of being represented by equation (Rth) and the face.

Re＝(nx-ny)·d

Rth＝(nx-nz)·d

In the superincumbent equation, nx, ny, nz represent the refractive index on X-direction, Y direction and the Z-direction in the lamination retardation plate; X-direction be in the lamination retardation plate plane refractive index maximum axially, Y direction be in this plane perpendicular to X-axis axially, and Z-direction is perpendicular to the thickness direction of X-axis and Y-axis; The d presentation layer is pressed the thickness of retardation plate.

The inventor has been found that optical anisotropic layer of being made by polymkeric substance by lamination (A) and the optical anisotropic layer of being made by non-liquid crystal polymer (for example polyimide) (B), the lamination retardation plate of can obtain having good optical property (for example postponing (Re) and 50 nanometers or bigger difference (Rth-Re) in 10 nanometers or the bigger face) and less thickness.In addition, this lamination retardation plate can prevent painted, and when using separately Kapton that big length of delay is provided on thickness direction in routine techniques, may take place painted.Therefore, lamination retardation plate of the present invention is useful, because for instance, when being used for various image displays (for example LCD), lamination retardation plate of the present invention shows good display characteristic, and wide viewing angle characteristics for example can reduce the thickness of device self in addition.

Description of drawings

Fig. 1 is the cut-open view of an example of lamination polaroid according to embodiments of the present invention.

Fig. 2 is the cut-open view according to an example of the lamination polaroid of another embodiment of the invention.

Fig. 3 is the cut-open view according to an example of the lamination polaroid of another embodiment of the present invention.

Fig. 4 is the cut-open view according to an example of the lamination polaroid of another embodiment of the present invention.

Fig. 5 is the cut-open view according to an example of the lamination polaroid of another embodiment of the present invention.

Fig. 6 is the cut-open view according to an example of the lamination polaroid of another embodiment of the present invention.

Fig. 7 is the cut-open view according to an example of the lamination polaroid of another embodiment of the present invention.

Fig. 8 is the cut-open view according to an example of the lamination polaroid of another embodiment of the present invention.

Embodiment

As mentioned above, lamination retardation plate of the present invention comprises optical anisotropic layer of being made by polymkeric substance (A) and the optical anisotropic layer of being made by at least a non-liquid crystal polymer that is selected from polyamide, polyimide, polyester, polyaryletherketone, polyetherketone, polyamidoimide and the polyester-imide (B) at least, it is characterized in that postponing (Re) in the face is 10 nanometers or bigger, and the difference (Rth-Re) that postpones between (Re) in thickness direction retardation (Rth) and the face is 50 nanometers or bigger.

In the lamination retardation plate of the present invention that passes through laminated optical anisotropic band (A) and (B) form, refractive index on X-axis, Y-axis and the Z axle totally satisfies ' the relation of nx＞ny＞nz ', in addition, the Re value is 10 nanometers or bigger, and the difference between Rth and the Re (Rth-Re) is 50 nanometers or bigger.Therefore for instance, in above-mentioned VA mode LCD or ocb mode liquid crystal display, can compensate the birefringence of liquid crystal display cells fully, thereby provide extraordinary effect aspect the expansion visual angle.When the Re value is lower than 10 nanometers or Rth-Re and is lower than 50 nanometers, can not obtain the effect at above-mentioned expansion visual angle.

The value of preferred Re is in the scope of 10 to 500 nanometers, more preferably in the scope of 20 to 300 nanometers.The value of also preferred (Rth-Re) is in the scope of 50 to 1000 nanometers, more preferably in the scope of 50 to 900 nanometers, and in the scope particularly preferably in 50 to 800 nanometers.

Rth is 60 nanometers or bigger, and preferred in the scope of 60 to 1500 nanometers, more preferably in the scope of 60 to 1400 nanometers, and in the scope particularly preferably in 60 to 1300 nanometers.For lamination retardation plate of the present invention, Rth/Re is 1 or bigger.

In the present invention, for restriction especially of optical anisotropic layer (A), as long as with optical anisotropic layer (B) when combining, can satisfy above-mentioned Re and condition (Rth-Re) on the whole.But for instance, preferably postponing [Re (A)] in the face of being represented by equation is 20 to 300 nanometers, and ratio [Rth (A)]/[Re (A)] that postpones [Re (A)] in the thickness direction retardation of being represented by equation [Rth (A)] and the face is 1.0 or bigger.For instance, in thickness direction retardation [Rth (A)] and face ratio [Rth (A)]/[Re (A)] of delay [Re (A)] less than 1.0 situation under, therefore this layer length of delay on the compensation thickness direction fully reduced angular field of view when being used for LCD.When postponing less than 20 nanometers or greater than 300 nanometers face to face, the visual angle also will narrow down.More preferably, Rth (A)/Re (A) is 1.2 or bigger, and is preferably 1.2 to 40 especially.

Re(A)＝(nx(A)-ny(A))·d(A)

Rth(A)＝(nx(A)-nz(A))·d(A)

In the superincumbent equation, nx (A), ny (A), nz (A) represent the refractive index on X-direction, Y direction and the Z-direction in the optical anisotropic layer (A); X-direction be in anisotropic band (A) plane refractive index maximum axially, Y direction be in this plane perpendicular to X-axis axially, and Z-direction is perpendicular to the thickness direction of X-axis and Y-axis; D represents the thickness (being equally applicable to hereinafter) of anisotropic band (A).

Refractive index for optical anisotropic layer (B) has no particular limits, as long as it is the above-mentioned optical anisotropic layer of being made by non-liquid crystal polymer.Refractive index on X-axis, Y-axis and Z axle satisfies ' relation of nx (B)＞ny (B)＞nz (B) ', the perhaps satisfied ' relation of nx (B) ≈ ny (B)＞nz (B) ' but for instance.Nx (B), ny (B), nz (B) represent the refractive index on X-direction, Y direction and the Z-direction in the optical anisotropic layer (B) respectively.X-direction be in anisotropic band (B) plane refractive index maximum axially, Y direction be in this plane perpendicular to X-axis axially, and Z-direction is perpendicular to the thickness direction (being equally applicable to hereinafter) of X-axis and Y-axis.

When optical anisotropic layer (B) shows ' during the concerning of nx (B)＞ny (B)＞nz (B) ', preferably postponing [Re (B)] in the face of being represented by equation is 3 nanometers or bigger, and ratio [Rth (B)]/[Re (B)] that postpones [Re (A)] in the thickness direction retardation of being represented by equation [Rth (B)] and the face is 1.0 or bigger.For instance, in thickness direction retardation [Rth (B)] and face ratio [Rth (B)]/[Re (B)] of delay [Re (B)] less than 1.0 situation under, this plate length of delay on the compensation thickness direction fully causes narrower angular field of view when being used for LCD.Re (B) is 3 to 800 nanometers more preferably, and are preferably especially in 5 to 500 nanometers.Rth (B)/Re (B) more preferably 1.2 or bigger, and are preferably 1.2 to 160 especially.Equation below, the thickness (being equally applicable to hereinafter) of d (B) expression anisotropic band (B).

Re(B)＝(nx(B)-ny(B))·d(B)

Rth(B)＝(nx(B)-nz(B))·d(B)

Even if show at optical anisotropic layer (B) ' under the situation of nx (B) ≈ ny (B)＞nz (B) ' relation, postpone [Re (B)] in that is to say face to face when being essentially 0 nanometer, for instance, by being set in the above-mentioned scope with postponing Re (A) in the face of optical anisotropic layer (A), the Re of lamination retardation plate of the present invention and (Rth-Re) still can satisfy above-mentioned condition.

The instantiation of optical anisotropic layer (A) and optical anisotropic layer (B) combination comprise for instance that to postpone [Re (A)] in the face be 20 to 300 nanometers and thickness direction retardation [Rth (A)] with face in postpone [Re (A)] ratio [Rth (A)]/[Re (A)] be 1.0 or bigger optical anisotropic layer (A), with to postpone [Re (B)] in the face be 3 nanometers or bigger and thickness direction retardation [Rth (B)] with face in postpone [Re (A)] ratio [Rth (B)]/[Re (B)] be 1.0 or the combination of bigger optical anisotropic layer (B).

Lamination retardation plate of the present invention has 1 millimeter or littler integral thickness usually, therefore compares with above-mentioned conventional lamination retardation plate, and thickness is reduced fully.Preferred its thickness range is 1 to 500 micron, and particularly preferred scope is 5 to 300 microns.Half of the thickness that the thickness of lamination retardation plate of the present invention can be reduced to for instance is above-mentioned " the lamination retardation plate that forms by two stretching polymer films of lamination (the free end uniaxial tension of described thin polymer film to be to provide ' nx＞ny=nz ', and wherein the slow axis in two stretching polymer film planes intersects mutually with the right angle) ".

Optical anisotropic layer (A) has from 1 to 800 micron, and perhaps preferably from 5 to 500 microns, more preferably from 10 to 400 microns, and preferred from 50 to 400 microns thickness especially.Optical anisotropic layer (B) has from 1 to 50 micron for instance, and perhaps preferably from 2 to 30 microns, and preferred from 1 to 20 micron thickness especially.Because the thickness of optical anisotropic layer (B) can be reduced fully, so the integral thickness of lamination retardation plate of the present invention also can be lowered, and the lamination retardation plate will have the optical property of improving by laminated optical anisotropic band (A).

Although for not restriction especially of the material that forms optical anisotropic layer (A), for instance, the polymkeric substance that shows positive birefringence is preferred.By selective polymer, can increase interior the delay and thickness direction retardation of face of optical anisotropic layer (A).In the present invention, " polymkeric substance of performance positive birefringence " means the polymkeric substance that shows refraction maximization feature when oriented film on draw direction.The optical anisotropic layer of being made by this polymkeric substance (A) can be oriented film or non-stretching film (being equally applicable to hereinafter).

Because oriented film can be an embodiment of optical anisotropic layer (A), so the thermoplastic polymer that preferably is stretched easily of polymkeric substance for instance.The example of thermoplastic polymer comprises polyolefin (for example tygon and polypropylene), the polymkeric substance based on polynorbornene, polyester, Polyvinylchloride, polyacrylonitrile, polysulfones, polyacrylate, polyvinyl alcohol (PVA), polymethacrylate, polyacrylic ester, cellulose esters, and their multipolymer.These polymkeric substance can use separately, and perhaps two or more combination of polymers are used.The thin polymer film of describing among the JP2001-343529A (WO01/37007) also can be used for optical anisotropic layer (A).An example of polymeric material is to comprise side chain to have the thermoplastic resin of replacement or unsubstituted imide and the resin combination that side chain has the thermoplastic resin of replacement or unsubstituted phenyl and cyano group.The example is to comprise to comprise isobutylene and the alternating copolymer of N-methylene maleimide and the resin combination of styrene-acrylonitrile copolymer.Described thin polymer film forms by the extrusion resin composition for instance.Preferred described thin polymer film has good transparency.

Optical anisotropic layer (B) is formed by the non-liquid crystal polymer in aspect excellences such as thermotolerance, chemical resistance, transparencies, and the example is polyamide, polyimide, polyester, polyaryletherketone, polyetherketone, polyamidoimide and polyester-imide.Different with liquid crystal material, for instance, no matter how substrate is orientated, because the characteristic of himself, this non-liquid crystal material all can form the film of the optics uniaxiality that shows ' nx＞nz ' and ' ny＞nz '.Therefore for instance, the substrate that uses when forming anisotropic band (B) is not limited to orientation substrate, for instance even can directly use the substrate that does not stretch.

These polymkeric substance can use separately, perhaps have different multi-functional polymeric blends as at least two kinds and use, for example the potpourri of polyaryletherketone and polyamide.In these polymkeric substance, especially preferred polyimide is because it has the high grade of transparency, high orientation and high stretch matter.

Although the molecular weight to polymkeric substance is not particularly limited, for instance, weight-average molecular weight (Mw) is preferably 1,000 to 1,000, in 000 the scope, and more preferably in 2,000 to 500,000 scope.For instance, use polyethylene oxide as standard model, and DMF (N, dinethylformamide) is as solvent, (GPC) measures weight-average molecular weight by gel permeation chromatography.

As polyimide, preferably use the polyimide that has the interior orientation of high face and be dissolved in organic solvent.For instance, can use 9, the polycondensation polymer of fragrant four carboxylic acid's dianhydride of describing among two (ammonia aryl) fluorenes of 9-and the JP2000-511296 A, more specifically saying so comprises at least one polymkeric substance by the repetitive of following chemical formula (1) expression.

In the superincumbent chemical formula (1), R ³To R ⁶Be to be independently selected from hydrogen, halogen, phenyl, to be substituted with 1 to 4 halogen atom or a C ₁To C ₁₀The phenyl of alkyl, and C ₁To C ₁₀At least one substituting group in the alkyl.Preferably, R ³To R ⁶At least be to be independently selected from halogen, phenyl, to be substituted with 1 to 4 halogen atom or a C ₁To C ₁₀The phenyl of alkyl, and C ₁To C ₁₀A substituting group in the alkyl.

In the superincumbent chemical formula (1), for instance, Z is C _6-20The tetravalence aromatic group, and preferably pyromellitic acid group (pyromellitic group), the aromatic group of many rings, the derivant of many cyclophanes perfume base are by the group of following chemical formula (2) expression.

In the superincumbent chemical formula (2), Z ' is covalent bond, C (R for instance ⁷) ₂Group, CO group, O atom, S atom, SO ₂Group, Si (C ₂H ₅) ₂Group, perhaps NR ⁸Group.When a plurality of Z ', they can be identical or different.Equally, w is from 1 to 10 integer.R ⁷Be hydrogen or C (R independently ⁹) ₃R ⁸Be hydrogen, have 1 alkyl, perhaps a C to about 20 carbon atoms _6-20Aromatic group, and as a plurality of R ⁸The time, they can be identical or different.R ⁹Be hydrogen, fluorine or chlorine independently.

For instance, above-mentioned many cyclophanes perfume base group can be the quaternary groups derived from naphthalene, fluorenes, benzofluorene or anthracene.In addition, the substitutive derivative of above-mentioned many cyclophanes perfume base group can be for example to be substituted with to be selected from C _1-10Above-mentioned many cyclophanes perfume base group of at least one group in alkyl, their fluoro derivatives and the halogen (for example F and Cl).

In addition, for instance, can use the homopolymer of repetitive, perhaps the polyimide that disclosed repetitive is represented by following general formula (5) among JP 8 (1996)-511812 A by following general formula (3) or (4) expression.Polyimide by following general formula (5) expression is the preference pattern of the homopolymer of general formula (3) expression.

Superincumbent chemical formula (3) is in (5), and G and G ' are and for example are independently selected from covalent bond, CH ₂Group, C (CH ₃) ₂Group, C (CF ₃) ₂Group, C (CX ₃) ₂Group (wherein X is a halogen), CO group, O atom, S atom, SO ₂Group, Si (C ₂H ₅) ₂Group and N (CH ₃) group in the group, and G can be identical or different with G '.

In superincumbent chemical formula (3) and (5), L is a substituting group, and d and e represent substituent quantity herein.For instance, L is halogen, C _1-3Alkyl, halo C _1-3Alkyl, phenyl, the perhaps phenyl of Qu Daiing, and when a plurality of L, they can be identical or different.Above-mentioned substituted-phenyl can be to have the halogen of being selected from, C for instance _1-3Alkyl, halo C _1-3The substituent substituted-phenyl of in the alkyl at least one.In addition, above-mentioned halogen can be fluorine, chlorine, bromine or iodine for instance.D is from 0 to 2 integer, and e is from 0 to 3 integer.

Superincumbent chemical formula (3) is in (5), and Q is a substituting group, and f represents substituent quantity herein.For instance, Q can be atom or be selected from group in hydrogen, halogen, alkyl, substituted alkyl, nitro, cyano group, sulfane base, alkoxy, aryl, substituted aryl, carbalkoxy and the replacement carbalkoxy that when a plurality of Q, they can be identical or different.Above-mentioned halogen can be fluorine, chlorine, bromine or iodine for instance.Above-mentioned substituted alkyl for example can be a haloalkyl.F is from 0 to 4 integer, and g and h are respectively from 0 to 3 integer and from 1 to 3 integer.In addition, preferred g and h are greater than 1.

In the superincumbent chemical formula (4), R ¹⁰And R ¹¹It is the group that is independently selected from hydrogen, halogen, phenyl, substituted-phenyl, alkyl and the substituted alkyl.Particularly preferably, R ¹⁰And R ¹¹Be haloalkyl independently.

In the superincumbent chemical formula (5), M ¹And M ²Can be identical or different, and be halogen, C for instance _1-3Alkyl, halo C _1-3Alkyl, phenyl, the perhaps phenyl of Qu Daiing.Above-mentioned halogen can be fluorine, chlorine, bromine or iodine for instance.Above-mentioned substituted-phenyl can be to have the halogen of being selected from, C for instance _1-3Alkyl, halo C _1-3The substituent substituted-phenyl of in the alkyl at least one.

Comprise polyimide by the instantiation of the polyimide of chemical formula (3) expression by following chemical formula (6) expression.

In addition, except the multipolymer with above-mentioned skeleton (repetitive), described polyimide can also be other multipolymer that obtains by suitably copolymerization acid anhydrides and diamines for instance.

Above-mentioned acid anhydrides can be fragrant four carboxylic acid's dianhydride for instance.Fragrant four carboxylic acid's dianhydride can be pyromellitic dianhydride, benzophenone tetracarboxylic dianhydride, naphthalene tetracarboxylic acid dianhydride, heteroaromatic tetracarboxylic dianhydride for instance, perhaps the diphenyl tetracarboxylic dianhydride of 2,2 '-replacement.

Pyromellitic dianhydride can be the equal tetracarboxylic acid dianhydride of benzene, 3 for instance, the equal tetracarboxylic acid dianhydride of 6-diphenyl benzene, 3, the two equal tetracarboxylic acid dianhydrides of (trifluoromethyl) benzene, 3 of 6-, the equal tetracarboxylic acid dianhydride of 6-dibromobenzene, perhaps 3, the equal tetracarboxylic acid dianhydride of 6-dichloro-benzenes.Benzophenone tetracarboxylic dianhydride can be 3,3 ', 4 for instance, 4 '-benzophenone tetracarboxylic dianhydride, 2,3,3 ', 4 '-benzophenone tetracarboxylic dianhydride or 2,2 ', 3,3 '-benzophenone tetracarboxylic dianhydride.The naphthalene tetracarboxylic acid dianhydride can be 2,3,6 for instance, 7-naphthalene tetracarboxylic acid dianhydride, 1,2,5,6-naphthalene tetracarboxylic acid dianhydride or 2,6-two chloro-1,4,5,8-naphthalene tetracarboxylic acid dianhydride.The heteroaromatic tetracarboxylic dianhydride can be thiophene-2,3,4 for instance, 5-tetracarboxylic dianhydride, pyrazine-2,3,5,6-tetracarboxylic dianhydride or pyridine-2,3,5,6-tetracarboxylic dianhydride.The diphenyl tetracarboxylic dianhydride of 2,2 '-replacement can be 2,2 '-two bromo-4,4 ', 5 for instance, 5 '-diphenyl tetracarboxylic dianhydride, 2,2 '-two chloro-4,4 ', 5,5 '-diphenyl tetracarboxylic dianhydride or 2,2 '-two (trifluoromethyl)-4,4 ', 5,5 '-diphenyl tetracarboxylic dianhydride.

Other example of fragrant four carboxylic acid's dianhydride comprises 3,3 ', 4,4 '-diphenyl tetracarboxylic dianhydride, two (2,3-dicarboxyl phenyl) methane dianhydride, two (2,5,6-three fluoro-3,4-dicarboxyl phenyl) the methane dianhydride, 2,2 '-two (3,4-dicarboxyl phenyl)-1,1,1,3,3, the 3-hexafluoropropane dianhydride, 4,4 '-(3,4-dicarboxyl phenyl)-2,2-diphenyl propane dianhydride, two (3,4-dicarboxyl phenyl) ether dianhydride, 4,4 '-oxygen phthalic acid dianhydride, two (3,4-dicarboxyl phenyl) sulfonic acid dianhydride, (3,3 ', 4,4 '-diphenyl sulfone tetracarboxylic dianhydride), 4,4 '-[4,4 '-isopropylidene-two (p-phenylene oxygen)] two (phthalic anhydrides), N, N '-(3,4-dicarboxyl phenyl)-N-methylamine dianhydride and two (3,4-dicarboxyl phenyl) diethylsilane dianhydride.

Wherein, fragrant four carboxylic acid's dianhydride is the diphenyl tetracarboxylic dianhydride of 2,2 '-replacement preferably, is more preferably 2,2 '-two (trihalomethyl)-4,4 ', 5,5 '-diphenyl tetracarboxylic dianhydride, and be more preferably 2,2 '-two (trifluoromethyl)-4,4 ', 5,5 '-diphenyl tetracarboxylic dianhydride.

Above-mentioned diamines can be aromatic diamines for instance.Their example comprises phenylenediamine, diaminobenzophenone, naphthylenediamine, heteroaromatic diamines, and other aromatic diamines.

Phenylenediamine can be to be selected from for example phenylenediamine, 2 of o-, m-and p-phenyl diamines, 4-diaminotoluene, 1,4-diamido-2-methoxybenzene, 1,4-diamido-2-phenyl benzene and 1,3-diamido-4-chlorobenzene for instance.The example of diaminobenzophenone comprises 2,2 '-diaminobenzophenone and 3,3 '-diaminobenzophenone.Naphthylenediamine can be 1 for instance, 8-diaminonaphthalene or 1,5-diaminonaphthalene.The example of heteroaromatic diamines comprises 2,6-diamino-pyridine, 2,4-diamino-pyridine and 2,4-diamido-S-triazine.

In addition, except above-claimed cpd, aromatic diamines can be 4,4 '-benzidine, 4,4 '-diaminodiphenylmethane, 4,4 '-(9-fluorenylidene)-diphenylamine, 2,2 '-two (trifluoromethyl)-4,4 '-benzidine, 3,3 '-two chloro-4,4 '-diaminodiphenylmethane, 2,2 '-two chloro-4,4 '-benzidine, 2,2 ', 5,5 '-tetrachloro benzidine, 2, two (the 4-di (amino-phenoxy) benzene base) propane of 2-, 2, two (4-aminophenyl) propane of 2-, 2, two (the 4-aminophenyls)-1,1,1 of 2-, 3,3, the 3-HFC-236fa, 4,4 '-diaminodiphenyl ether, 3,4 '-diaminodiphenyl ether, 1, two (3-amino-benzene oxygen) benzene of 3-, 1, two (4-amino-benzene oxygen) benzene of 3-, 1, two (4-amino-benzene oxygen) benzene of 4-, 4,4 '-two (4-amino-benzene oxygen) biphenyl, 4,4 '-two (3-amino-benzene oxygen) biphenyl, 2, two [4-(4-amino-benzene oxygen) phenyl] propane of 2-, 2, two [4-(4-amino-benzene oxygen) phenyl]-1 of 2-, 1,1,3,3, the 3-HFC-236fa, 4,4 '-diamino-diphenyl thioether, perhaps 4,4 '-diamino-diphenyl sulfone.

Polyetherketone as the form dielectric grid layer material can be disclosed polyaryletherketone by following general formula (7) expression among the JP 2001-49110A for instance.

In the superincumbent chemical formula (7), X is a substituting group, and q represents substituent quantity herein.For instance, X be halogen atom, low alkyl group, haloalkyl, lower alkoxy or, perhaps halogenated alkoxy, and when a plurality of X, they can be identical or different.

Above-mentioned halogen atom can be fluorine atom, bromine atoms, chlorine atom or iodine atom for instance, and wherein fluorine atom is preferred.For instance, low alkyl group C preferably _1-6Lower straight alkyl or C _1-6Rudimentary branched alkyl, and be more preferably C _1-4The straight or branched alkyl.More particularly, it is methyl, ethyl, propyl group, isopropyl, butyl, isobutyl, sec-butyl or the tert-butyl group preferably, and especially preferably methyl and ethyl.Haloalkyl can be the halides of above-mentioned low alkyl group, for example trifluoromethyl for instance.For instance, lower alkoxy C preferably _1-6The straight or branched alkoxy, and be more preferably C _1-4The straight or branched alkoxy.More particularly, it is methoxyl, ethoxy, propoxyl group, isopropoxy, butoxy, isobutoxy, sec-butoxy or tert-butoxy preferably, and especially preferably methoxyl and ethoxy.Halogenated alkoxy can be the halides of above-mentioned lower alkoxy, for example trifluoromethoxy for instance.

In the superincumbent chemical formula (7), q is from 0 to 4 integer.In chemical formula (7), preferred q=0, and have carbonyl and the ether oxygen atom that is connected with the phenyl ring two ends in contraposition.

In addition, in the superincumbent chemical formula (7), R ¹Be group, and m is 0 to 1 integer by following chemical formula (8) expression.

In the superincumbent chemical formula (8), X ' is a substituting group, and for instance with chemical formula (7) in identical.In chemical formula (8), when a plurality of X ', they can be identical or different.Q ' represents substituent quantity among the X ', and is from 0 to 4 integer, preferably q '=0.In addition, p is 0 or 1 integer.

In chemical formula (8), R ²It is the aromatic group of divalence.This divalence aromatic group is o-, m-or p-phenylene or derived from the divalent group of naphthalene, biphenyl, anthracene, o-, m-or p-triphenyl, phenanthrene, dibenzofurans, diphenyl ether or diphenylsulphone for instance.In these divalence aromatic groups, hydrogen direct and the aromatic group bonding can use halogen atom, low alkyl group or lower alkoxy to replace.Wherein, R ²Preferably be selected from the aromatic group in the following chemical formula (9) to (15).

In the superincumbent chemical formula (7), R ¹Preferably by the group of following chemical formula (16) expression, R wherein ²With identical in p and the above-mentioned chemical formula (8).

In addition, in chemical formula (7), n represents the degree of polymerization, and scope from 2 to 5000 for instance, preferably from 5 to 500.Polymerization can be made up of the repetitive with same structure or different structure.In latter instance, the polymerized form of repetitive can be block polymerization or polymerization at random.

In addition, preferably, be fluorine by the end of the right-tetrafluoro benzoylene side of the polyaryletherketone of chemical formula (7) expression, and the end of its oxyalkylene side is a hydrogen atom.Such polyaryletherketone can be represented by following general formula (17).In the chemical formula below, the n and the same degree of polymerization of representing in chemical formula (7).

The instantiation of the polyaryletherketone of chemical formula (7) expression comprises those compounds by following chemical formula (18) to (21) expression, wherein, and the n and the same degree of polymerization of representing in chemical formula (7).

Except above-claimed cpd, can be polyamide or the polyester that JP 10 (1998)-508048 A describe for instance as the polyamide of form dielectric grid layer material or polyester, and their repetitive can be represented by following general formula (22).

In the superincumbent chemical formula (22), Y is O or NH.E is selected from covalent bond, C ₂Thiazolinyl, halo C ₂Thiazolinyl, CH ₂Group, C (CX ₃) ₂Group (wherein X is halogen or hydrogen), CO group, O atom, S atom, SO ₂Group, Si (R) ₂At least one group in group and N (R) group, and E can be identical or different.In above-mentioned E, R is C _1-3Alkyl and halo C _1-3In the alkyl one of at least, and be positioned at carbonyl functional group or Y group between position or contraposition.

In addition, in the superincumbent chemical formula (22), A and A ' are substituting groups, and t and z represent substituting group quantity herein respectively.In addition, p is from 0 to 3 integer, and q is from 1 to 3 integer, and r is from 0 to 3 integer.

Above-mentioned A is selected from hydrogen, halogen, C for instance _1-3Alkyl, halo C _1-3Alkyl, with alkoxy, aryl, halogenated aryl, the C of OR (wherein R is as group defined above) expression _1-9Alkoxy carbonyl, C _1-9Alkyl carbonyl oxy, C _1-12Aryloxycarbonyl, C _1-12Aryl-carbonyl oxygen and substitutive derivative thereof, C _1-12Aryl-amino-carbonyl, and C _1-12Aryl carbonyl amino and derivant thereof.When a plurality of A, they can be identical or different.Above-mentioned A ' is selected from halogen, C for instance _1-3Alkyl, halo C _1-3The phenyl of alkyl, phenyl and replacement, and when a plurality of A ', they can be identical or different.Substituting group on the phenyl ring of substituted-phenyl can be halogen, C for instance _1-3Alkyl, halo C _1-3Alkyl or their combination.T is from 0 to 4 integer, and z is from 0 to 3 integer.

In the polyamide of chemical formula (22) expression in the above or the repetitive of polyester, the repetitive of being represented by following general formula (23) is preferred.

In formula (23), definition is identical in A, A ' and Y and the chemical formula (22), and v is from 0 to 3 integer, preferably from 0 to 2 integer.Although each x and y are 0 or 1, both are not 0 entirely.

Then, lamination retardation plate of the present invention can be produced by following mode.

At first, prepare the optical anisotropic layer of making by polymkeric substance (A).As mentioned above, this optical anisotropic layer (A) is not particularly limited, as long as it have postpone in the face of 20 to 300 nanometers [Re (A)] and 1.0 or bigger thickness direction retardation [Rth (A)] and face in ratio [Rth (A)]/[Re (A)] of delay [Re (A)].This thin polymer film can be aforesaid non-stretching film or oriented film.For instance, it can sprawl the thin polymer film that forms and obtain by stretching by extruding or flowing.Oriented film can be single axle drawn membrane or biaxially oriented film.

Similarly, drawing process is not particularly limited, and can use conventional known drawing process for instance, for example uniaxial tension (as the roll shaft longitudinal stretching) and biaxial stretch-formed (as the stenter cross directional stretch).The roll shaft longitudinal stretching uses the roll shaft of heating to implement, and perhaps implements in the atmosphere of heating.These methods can be used together.Biaxial stretch-formed can be that order biaxial stretch-formed or use roll shaft and stenter is biaxial stretch-formed when only using stenter.Draw ratio is not particularly limited, determines but can wait suitably according to drawing process, material for instance.As for characteristic, preferred optical anisotropic layer (A) has excellent surface flatness, uniform birefringence, the transparency and thermotolerance.

Stretching prepolymer film is generally 10 to 800 microns, and is preferably 10 to 700 microns.And, the thin polymer film after the stretching, promptly optical anisotropic layer (A) has above-mentioned thickness.

On the other hand, (B) is not particularly limited to optical anisotropic layer, as long as it have postpone in 3 nanometers or the bigger face [Re (A)] and 1.0 or bigger thickness direction retardation [Rth (A)] and face in ratio [Rth (A)]/[Re (A)] of delay [Re (A)].For instance, it can prepare by following mode.

For instance, form film by the non-liquid crystal polymer of coating on substrate, and by the non-liquid crystal polymer of curing in coating, thereby optical anisotropic layer (B) on substrate, formed.No matter the arrangement of substrate how, non-liquid crystal polymer (for example polyimide) itself shows ' nx＞nz ', ' ny＞nz ' (optical characteristics of nx＞ny=nz).Therefore, can form the optical anisotropic layer that shows the optics uniaxiality, promptly only on thickness direction, postpone.Optical anisotropic layer (B) can use with the state that separates with substrate, perhaps uses with the state that forms in substrate.

At this moment, preferred optical anisotropic layer (A) is used as substrate.When this optical anisotropic layer (A) when being used as substrate, can directly be coated with non-liquid crystal polymer in the above, do not need to use pressure-sensitive bonding agent to come laminated optical anisotropic band (A) and (B), thereby can reduce the quantity of the layer that needs lamination, thereby further reduce the thickness of laminate.

As mentioned above, because non-liquid crystal polymer has the optics uniaxiality, so do not need to use substrate to be orientated.Therefore, orientation substrate and non-orientation substrate can be used as substrate.In addition, substrate can have the delay that is caused by birefringence for instance, does not perhaps have this delay that is caused by birefringence.The transparent substrates that produces delay owing to birefringence can be oriented film etc. for instance, and this film has the birefringence of controlling on thickness direction.For instance, can be by with heat-schrinkable film mucoadhesive polymers film, and further heat and the method that stretches is controlled birefringence.

Although the method for the non-liquid crystal polymer of coating in substrate is not particularly limited, but their example comprises the non-liquid crystal polymer of heat fused, Tu Bu method is perhaps dissolved non-liquid crystal polymer in solvent again, thereby prepares the method for polymer solution and coating.Because good operability, so the method for coated polymeric solution is particularly preferred.

Polymer concentration in the polymer solution is not particularly limited, but for instance with respect to 100 parts by weight solvent, non-liquid crystal polymer is preferably at 5 to 50 weight portions, and more preferably in the scope of 10 to 40 weight portions, thereby the viscosity of being convenient to be coated with is provided.

Solvent to polymer solution is not particularly limited, as long as the material of its energy solution such as non-liquid crystal polymer, and can suitably select according to the kind of polymkeric substance.Their instantiation comprises halogenated hydrocarbons, for example chloroform, methylene chloride, phenixin, ethylene dichloride, tetrachloroethane, triclene, zellon, chlorobenzene and o-dichlorobenzene; Phenol, for example phenol and parachlorophenol; Aromatic hydrocarbon, for example benzene,toluene,xylene, methoxybenzene and 1,2-dimethoxy benzene; Ketone-based solvent, for example acetone, MEK, methyl isobutyl ketone, cyclohexanone, cyclopentanone, 2-Pyrrolidone and N-N-methyl-2-2-pyrrolidone N-; Ester group solvent, for example ethyl acetate and butyl acetate; Alcohol-based solvent, for example tert-butyl alcohol, glycerine, ethylene glycol, triethylene glycol, glycol monomethyl ether, diethylene glycol dimethyl ether, propylene glycol, dipropylene glycol and 2-methyl-2,4-pentanediol; Amide group solvent, for example dimethyl formamide and dimethyl acetamide; Itrile group solvent, for example acetonitrile and butyronitrile; Ether solvent, for example diethyl ether, dibutyl ethers and tetrahydrofuran; Perhaps carbon disulphide, ethyl cellosolve or butyl cellosolve.These solvents can use separately, and perhaps two or more are used in combination.

In polymer solution, can further mix different adjuvants, for example stabilizing agent, plastifier, metal etc. when needing.

In addition, polymer solution can comprise other resin, as long as the characteristics such as orientation of material descend not significantly.These resins can be resin, engineering plastics, thermoplastic resin and the thermoset resin that is used for purpose commonly used for instance.

The resin of purpose commonly used can be tygon (PE), polypropylene (PP), polystyrene (PS), polymethylmethacrylate (PMMA), ABS resin, AS resin etc. for instance.Nylon), polyethylene terephthalate (PET), polybutylene terephthalate (PBT) etc. engineering plastics can be poly-ethyl acetate (POM), polycarbonate (PC), polyamide (PA: for instance.Thermoplastic resin can be for instance polyphenylene sulfide (PPS), polyethersulfone (PES), polyketone (PK), polyimide (PI), poly terephthalic acid cyclohexanedimethanoester ester (polycyclohexanedimethanol terephthalate) (PCT), polyacrylate (PAR), liquid crystal polymer (LCP) etc.Thermoset resin can be epoxy resin, linear phenol-aldehyde resin etc. for instance.

When above-mentioned other resin is mixed in the above-mentioned polymer solution, for instance, potpourri with respect to the content range of polymkeric substance from 0 weight % to 50 weight %, preferably from 0 weight % to 30 weight %.

For instance, the method for coated polymeric solution be selected from spin-coating method, rolling method, flow coat method, printing, dip coating, flow sprawl (flow-expanding), rod is coated with method and intaglio plate rubbing method.In the coating, can use the method for stack polymeric layer when needing.

The non-liquid crystal polymer that forms coating can be solidified by the method for dry coating for instance.Drying means is not particularly limited, but can be air drying or heat drying for instance.Its condition can suitably be determined according to the type and the solvent of non-liquid crystal polymer for instance.For example, temperature is usually at 40 ℃ to 300 ℃, and preferably 50 ℃ to 250 ℃, and more preferably 60 ℃ to 200 ℃.The surface of coating can be under constant temperature or heat up gradually or cooling under dry.Also be not particularly limited drying time, but be generally 10 seconds to 30 minutes, is preferably 30 seconds to 25 minutes, and more preferably 1 minute to 20 minutes.

Because the solvent that is retained in the polymer solution in the optical anisotropic layer (B) may change the optical property of lamination retardation plate along with the time, be directly proportional with its amount, so the amount of solvent is preferably 5% or lower for instance, more preferably 2% or lower, and be preferably 0.2% or lower again.

In addition, show the optics biaxiality, promptly ' optical anisotropic layer of nx＞ny＞nz ' (B) can prepare by using the substrate that shows shrinkage character on the direction planar.Particularly for instance, non-liquid crystal polymer directly is coated in the substrate with shrinkage character, and forms coating in above-mentioned mode, and substrate is shunk then.Because suprabasil coating is shunk on in-plane along with the contraction of substrate,, thereby show optics biaxiality (nx＞ny＞nz) so coating planar will have refraction difference.Then, the non-liquid crystal polymer that forms coating is cured, thereby forms biaxiality optical anisotropic layer (B).

In order planar to provide shrinkage character on a direction, on the preferred direction planar substrate is stretched in advance.Stretch in advance by aforesaid, on the direction opposite, produce convergent force with draw direction.The difference of shrinking in the basal surface is used to provide the difference of the refraction in the face to the non-liquid crystal polymer of coating.Although be not particularly limited, from 10 to 200 microns for instance of the thickness ranges of substrate before stretching, preferably from 20 to 150 microns, and especially preferably from 30 to 100 microns.Draw ratio is not particularly limited.

Substrate can be shunk by heating after the formation coating in substrate in the above described manner.Although the condition of heating is not particularly limited, and can waits suitably according to type of material and determine that Jia Re temperature is preferably 50 ℃ to 200 ℃ at 25 ℃ to 300 ℃ for instance, and more preferably in 60 ℃ to 180 ℃ the scope.Although shrinkage degree is not particularly limited, when base length was 100% before shrinking for instance, shrinkage factor was higher than 0 and be not higher than 10%.

In addition, can also be by in substrate, forming coating as mentioned above, and with the coating transparent substrates that stretches, thus in substrate, form the optical anisotropic layer (B) that shows optics biaxiality (promptly ' nx＞ny＞nz ').According to this method,, will make coating planar have refraction difference, thereby show the optics biaxiality by the laminate of elongate substrate and coating together on the direction planar.Drawing process by substrate and coat composed laminate is not particularly limited.The example of drawing process comprises uniaxial tension (free end longitudinal stretching) in a longitudinal direction; When film is fixed in a longitudinal direction, uniaxial tension (stiff end cross directional stretch) in a lateral direction; And on the vertical and horizontal both direction oriented film (successively or simultaneously biaxial stretch-formed).Although can come the tensile layer compressing tablet by while elongate substrate and coating, because below, preferred elongate substrate.When elongate substrate, substrate is produced pulling force owing to stretching, thus the coating indirectly on the elongate substrate.Compare with the tensile layer compressing tablet, such stretching makes the coating individual layer obtain more uniform stretching, so the transparent substrates that only stretches can make coating be stretched uniformly.

Stretching condition is not particularly limited, determines but can wait according to the type of substrate and non-liquid crystal polymer for instance suitably.Although the temperature during stretching waits suitably and selects according to type, glass transition point (Tg), the additive types of substrate and non-liquid crystal polymer, but temperature range is from 80 ℃ to 250 ℃ for instance, preferably from 120 ℃ to 220 ℃, and more preferably from 140 ℃ to 200 ℃.Especially, temperature is substantially equal to or is higher than the Tg of base material.

By for example contact adhesive or bonding agent, optical anisotropic layer (A) and optical anisotropic layer (B) by lamination so obtains can form lamination retardation plate of the present invention.In addition, also can the optical anisotropic layer (B) that forms be gone up in substrate (first substrate) and be laminated on the optical anisotropic layer (A), therefrom peel off first substrate then by contact adhesive etc.

Be not particularly limited for bonding agent and contact adhesive, and can use for instance conventional known clear binder and contact adhesive based on acrylic substance, silicone, polyester, polyurethane, polyethers and rubber etc.Wherein, postpone the variation aspect of optical properties of materials from preventing lamination, preferred especially material therefor does not need pyroprocess to solidify or drying.Specifically, it is preferred not needing the acrylic pressure-sensitive adhesive of curing for a long time and dried.Adhesive bonding method is not limited to above-mentioned description, but as mentioned above, directly forms optical anisotropic layer (B) by using optical anisotropic layer (A) in the above as substrate, can form lamination retardation plate of the present invention.In this embodiment, for instance because can save pressure-sensitive adhesive layer and/or bonding coat, can reduce the quantity of the layer of wanting lamination, so reduced the thickness of lamination retardation plate.In addition, can also use optical anisotropic layer (A) as substrate, laminated optical anisotropic band (B) in the above, and the laminate of the gained that further stretches as mentioned above as mentioned above, and/or shrink optical anisotropic layer (A), so that optical anisotropic layer (B) also is retracted.

In addition, preferred lamination retardation plate of the present invention also has pressure-sensitive adhesive layer or bonding coat on outermost layer.This bonding coat or pressure-sensitive adhesive layer are convenient to that lamination retardation plate of the present invention is adhered to other optical layers or for example on other element of liquid crystal cell, and can also prevent peeling off of lamination retardation plate of the present invention.Pressure-sensitive adhesive layer can be one of outermost layer of lamination retardation plate, perhaps is in turn laminated on two outermost layers.

Material to pressure-sensitive adhesive layer is not particularly limited, and it can be conventional material known, for example acrylate copolymer.In addition, from preventing bending because of absorbing foaming that moisture causes or the deterioration of peeling off, prevent optical property and causing because of the difference of thermal expansivity, and the angle that forms the image display with high-quality and excellent durability considers that the pressure-sensitive adhesive layer with low humidity aspiration receipts coefficient and excellent heat resistance is preferred.Fine grained can also be added in the contact adhesive, show the pressure-sensitive adhesive layer of light diffusion character with formation.In order on the surface of lamination retardation plate, to form pressure-sensitive adhesive layer, the solution or the molten mass of jointing material can be applied directly on the predetermined surface of polaroid by extended method (for example flow and sprawl and coating process) for instance.In addition, also can on following liner, form pressure-sensitive adhesive layer in an identical manner, it be transferred on the predetermined surface of lamination retardation plate then.

Be arranged in exposure under the situation of the pressure-sensitive adhesion laminar surface on the lamination retardation plate, preferably use the liner covering surfaces.This can prevent that pressure-sensitive adhesive layer from being polluted before use.Can by being provided, the suitable film (for example above-mentioned transparent membrane) that has release coating (for example silicone base remover, chain alkyl remover, fluorocarbon remover or molybdenum sulfide) form described liner as required for instance.

Pressure-sensitive adhesive layer can be individual layer or laminate.Laminate can comprise the individual layer that type or composition differ from one another.Two lip-deep pressure-sensitive adhesive layers that are arranged into polaroid can be mutually the same or different on type or composition.

The thickness of pressure-sensitive adhesive layer can wait suitably according to the component of polaroid to be determined.Usually, its thickness is from 1 to 500 micron.

Preferred pressure-sensitive adhesive layer is by having good optical property and for example contact adhesive of wettable, cohesiveness and fusible appropriate characteristics is formed.Contact adhesive suitably prepares based on following polymers: for example acrylate copolymer, silicone-based polymer, polyester, polyurethane, polyethers, and synthetic rubber.

The cohesive of pressure-sensitive adhesive layer can be controlled by conventional known method.For instance, can be based on the content ratio of the composition of the raw polymer that forms contact adhesive or molecular weight, cross-linking method, crosslinkable functionality, and the ratio of the crosslinking chemical that mixes, regulate degree of crosslinking and molecular weight.

Lamination retardation plate of the present invention can use separately as mentioned above, perhaps as required with any other optical element combination, be formed for the laminate that different optical is used.Specifically, it can be used as optical compensatory element.Although be not particularly limited, described for instance optical element can be polarizer of mentioning below etc.

Lamination polaroid of the present invention is the lamination polaroid that comprises optical thin film and polarizer, and wherein said optical thin film is a lamination retardation plate of the present invention.

Structure for polaroid is not particularly limited, as long as it has lamination retardation plate of the present invention, example is as follows.Polaroid of the present invention is not limited to following structure, as long as it has lamination retardation plate of the present invention and polarizer, but it can also comprise additional optics etc.Alternatively, also can be not with any additional optical element.

An example of lamination polaroid of the present invention has lamination retardation plate of the present invention, polarizer and two transparent protective seams for instance; wherein protective clear layer is laminated on two surfaces of polarizer by bonding coat, and the lamination retardation plate further is laminated on the protective clear layer by bonding coat.As the laminate of aforesaid optical anisotropic layer (A) and optical anisotropic layer (B), any one side of lamination retardation plate can be faced protective clear layer.

Protective clear layer can be in turn laminated on two surfaces of aforesaid polarizer, perhaps only is in turn laminated on the one surface.Be disposed under two lip-deep situations of polarizer at protective clear layer, each layer can be identical or different.Although the method for bonding each layer is not particularly limited, contact adhesive and bonding agent can be used for bonding coat, in addition, when each layer during by contact laminating, can save this bonding coat.

Another example of lamination polaroid has lamination retardation plate of the present invention, polarizer and protective clear layer; wherein protective clear layer is in turn laminated on the surface of polarizer by bonding coat, and the lamination retardation plate is in turn laminated on another surface of polarizer by bonding coat.

The laminate that forms because the lamination retardation plate is by bonding coat laminated optical anisotropic band (A) and optical anisotropic layer (B), its any one side is all towards polarizer.But for instance, preferably the lamination retardation plate is arranged, so that optical anisotropic layer (A) is towards polarizer.According to this structure, optical anisotropic layer of the present invention (A) can also be as the protective clear layer in the lamination polaroid.That is to say; two protective clear layers of lamination on two surfaces of polarizer not; but protective clear layer is laminated on the side surface of polarizer; and the lamination retardation plate is laminated on the opposite side surface; so that optical anisotropic layer (A) is towards the polarizer face, thereby optical anisotropic layer (A) also plays a part protective clear layer on polarizer.The polaroid thickness that makes is thus further reduced.

Polaroid is not particularly limited, and it can be that for example the dichroic material by for example iodine or dichroic dye is adsorbed onto on the various films by the film of conventional known method preparation, the colouring method then crosslinked, that stretching is also dry.Especially preferably the film of radiotransparency polarized light when incidence natural lights also preferably has the good light transmission and the film of degree of polarization.The example of the film of various absorption dichroic material comprises the hydrophilic polymer film, for example polyvinyl alcohol (PVA) (PVA) base film, the formalized PVA base film of part, based on the partly-hydrolysed film of vinyl-vinyl acetate copolymer, and cellulose base film.Except above-mentioned film, for instance, can use the polyenoid alignment films of for example dewater PVA and dehydrochlorination Polyvinylchloride.Wherein, the PVA base film is preferred.In addition, from 1 to 80 micron usually of the thickness of polaroid is although be not limited to this.

Protective seam is not particularly limited, and it can be conventional known transparent membrane.For instance, it is preferred having excellent transparency, physical strength, thermal stability, moisture shielding properties and isotropic transparent protective film.The instantiation that is used for the material of this protective clear layer comprises the cellulose base resin, for example tri acetyl cellulose and based on the transparent resin of following compounds: polyester, polycarbonate, polyamide, polyimide, polyethersulfone, polysulfones, polystyrene, polynorbornene, polyolefin, acrylic substance, acetic acid esters etc.Can also use thermoset resin or ultraviolet curable resin based on acrylic substance, urethane, acrylic acid urethane, epoxy, silicone etc.Wherein, from polarization properties and durability angle, the TAC film that has with the surface of saponification such as alkali is preferred.

In addition, can also use the thin polymer film of describing among the JP 2001-343529A (WO 01/37007).Used polymeric material can be to comprise side chain to have and replace or the not thermoplastic resin of substituted imido and the resin combination that side chain has the thermoplastic resin of replacement or unsubstituted phenyl and itrile group, for example comprises the resin combination of isobutylene and N-methylene maleimide alternating copolymer and acrylonitritrile-styrene resin.Alternatively, thin polymer film can form by the extrusion resin composition.

Preferred described protective seam is colourless.More particularly, the length of delay (Rth) on the film thickness direction of being represented by equation is preferably from-90 nanometers to+75 nanometers, more preferably from-80 nanometers to+60 nanometers, and especially preferably from-70 nanometers to+45 nanometers.When length of delay when-90 nanometers are to the scope of+75 nanometers, painted (optical clouration) of the polaroid that is caused by protective film can be solved fully.In the equation below, nx, ny and nz are all to recited above similar, and d represents the thickness of film.

Rth＝[{(nx+ny)/2}-nz]·d

Protective clear layer also has optical compensation function.As protective clear layer, can use for instance to be used for preventing perhaps being used to widen the known layer at preferred visual angle because of the visible angle that postpones based on liquid crystal cell changes painted known layer with optical compensation function.Concrete example comprises the oriented film of the various films that obtain by single shaft or biaxial stretch-formed above-mentioned transparent resin, liquid crystal polymer etc., and the laminate by providing the liquid crystal polymer oriented layer to obtain on transparent substrates.Wherein, the liquid crystal polymer oriented film is preferred, because it can be realized wide visual angle and have good visuality.The special preferably optical compensation retardation plate by obtaining with above-mentioned tri acetyl cellulose film even load optical compensating layer, wherein optical compensating layer is made by the tilted alignment layer of plate-like or nematic crystal polymkeric substance.This optical compensation retardation plate can be to be purchased product, for example by Fuji Photo Film Co., and " the WV film " that Ltd. produces.Alternatively, the optical compensation retardation plate can methods two-layer by lamination or thin-film carriers such as multilayer retardation films and tri acetyl cellulose film prepare, to control various optical properties (for example postponing).

Thickness to protective clear layer is not particularly limited, but for instance can be according to postponing or protecting intensity to come suitably to determine.Usually, its thickness is being not more than 500 microns, and preferably from 1 to 300 micron, and more preferably in from 5 to 150 microns the scope.

Protective clear layer can suitably form by conventional known method; for example be coated with the method for polarizing coatings with above-mentioned various transparent resins; perhaps the method for lamination transparent resin film, optical compensation laminate etc. on polarizing coating perhaps can be the product that is purchased.

For instance, can also carry out the processing of hard conating processing, anti-reflex treated, anti-stick, diffusion and anti-dazzle etc. to protective clear layer.Hard conating is handled and is intended to prevent the surface of polaroid of swiping, and is a kind of processing of being formed and being had the hard coat of excellent stiffness and smoothness by curable resin that provides on the surface of protective clear layer for instance.Curable resin can be silicone base, urethane groups, acrylic acid and epoxy radicals ultraviolet curable resin for instance.Described processing can be implemented by conventional known method.Anti-stick processing is intended to prevent that adjacent layer is adhering to each other.Anti-reflex treated is intended to prevent extraneous light in the lip-deep reflection of polaroid, and can wait and implement by forming conventional known anti-reflecting layer.

Anti-dazzle is handled and is intended to prevent that extraneous light is in the visuality of the lip-deep reflections affect light of polaroid by the polaroid propagation.For instance, anti-dazzle is handled can provide microscopic roughness to implement on the surface of protective clear layer by using conventional known method.This microscopic roughness for instance can be by sandblast or embossing and roughened surface perhaps provides by sneak into transparent fine grain method in above-mentioned transparent resin when forming protective clear layer.

Above-mentioned transparent fine grained can be silicon dioxide, aluminium oxide, titanium dioxide, zirconia, tin ash, indium oxide, calcium oxide, antimony oxide etc.In addition, can also use fine inorganic particles, perhaps comprise organic fine grained of crosslinked or no cross-linked polymer particle for instance with electric conductivity.Although be not particularly limited, from 0.5 to 20 micron for instance of transparent fine grain mean grain size.Usually, although be not particularly limited, the above-mentioned transparent resin of relative 100 parts of weight, transparent fine grain blending ratio is from 2 to 70 weight portions preferably, and more preferably from 5 to 50 weight portions.

Be mixed with transparent fine grain anti-dazzle photosphere itself and can be used as protective clear layer, perhaps as being applied to the lip-deep coating of protective clear layer.In addition, anti-dazzle photosphere also play a part diffusion see through polaroid light disperse layer, thereby widened visual angle (being the vision compensate function).

Except with protective clear layer is used in combination, above-mentioned anti-reflecting layer, anti-sticking layer, diffusing layer and anti-dazzle photosphere also can be in turn laminated to separately on the polaroid, make the laminate that comprises these optical layers.

The lamination of each assembly (optical anisotropic layer (A), optical anisotropic layer (B), lamination retardation plate, polarizer and protective clear layer) can be implemented by conventional known method, and is not particularly limited.Usually, can use above-mentioned contact adhesive, bonding agent etc., and can wait according to the type of each assembly and suitably select bonding agent or contact adhesive.Described bonding agent can be selected from the polymeric binder based on acrylic substance, vinyl alcohol, silicone, polyester, polyurethane, polyethers etc., and rubber-based adhesive.Even if these contact adhesives and bonding agent also are difficult to peel off under the influence of humidity or heat, and they are being excellent aspect optical clarity and the degree of polarization.Specifically, from the adhesion stability equal angles, preferably the PVA based adhesive is used for PVA base film polarizer.This bonding agent or contact adhesive can be applied directly on the surface of polarizer or protective clear layer.Alternatively, do to become band or the bonding agent or the pressure sensitive adhesive layer of sheet can be arranged from the teeth outwards.When bonding agent or contact adhesive are made into aqueous solution, can add other adjuvant or catalyzer as required, for example acid.Although the thickness to bonding coat is not particularly limited, thickness is from 1 nanometer to 500 nanometer for instance, preferably from 10 nanometer to 300 nanometers, and more preferably from 20 nanometer to 100 nanometers.Can use the conventional known method of the bonding agent of any use such as acrylate copolymer or vinyl alcohol based polyalcohol, and be not particularly limited.Alternatively, bonding agent can comprise water-solubility PVA based polyalcohol crosslinking chemical, for example glutaraldehyde, melamine and oxalic acid.Even if these bonding agents also are difficult to peel off under the influence of humidity or heat, and they are being excellent aspect optical clarity and the degree of polarization.For instance, these bonding agents can be used as aqueous solution and are applied on the surface of each assembly, and dry before use.In aqueous solution, can add other adjuvant or catalyzer when needing for instance, for example acid.Wherein, for bonding agent, from the cohesive of PVA film excellence, the PVA based adhesive is preferred.

Except above-mentioned polarizer, lamination retardation plate of the present invention can also use with the known optical element combination of routine, for example various retardation plates, diffusion control film, and brightness enhancing films.For instance, can be by single shaft or biaxial stretch-formed polymkeric substance, make polymkeric substance accept Z axle orientation, perhaps the coating of liquid crystalline polymkeric substance prepares retardation films in substrate.Diffusion control film can use diffusion, scattering and refraction to control the visual angle, perhaps controls dazzle and the scattered beam that influences sharpness.Brightness enhancing films can comprise the selective reflecting mirror of quarter wave plate (λ/4 plates) and cholesteric crystal, and the scattering film that the different polarization direction is had anisotropic scattering.In addition, optical thin film can combine with wire-grid polarizer for instance.

Lamination polaroid according to the present invention can also comprise additional optical layers except comprising lamination retardation plate of the present invention and polarizer.The example of described optical layers comprises conventional known and is used to form the various optical layers of LCD etc., for example polaroid, catoptron, half-mirror, and brightness enhancing films as described below.These optical layers can be used separately, perhaps two-layer at least being used in combination.This optical layers provides with individual layer, and perhaps at least two optical layers are by lamination.The lamination polaroid that preferably will comprise this optical layers is as the integrated polarizing sheet with optical compensation function, and it can be disposed on the surface of liquid crystal cell for instance, to be used for various image displays.

The integrated polarizing sheet is described below.

At first, will the example of reflection type polarizer or semitransparent reflector type polaroid be described.Reflection type polarizer by on the polaroid with optical compensation function according to the present invention again the lamination catoptron prepare, semitransparent reflector type polaroid then by on the polaroid with optical compensation function according to the present invention further the translucent catoptron of lamination prepare.

Usually, in order to make LCD (reflection LCD) from viewable side (demonstration side) reflection incident ray, this reflection type polarizer is disposed in the back side of liquid crystal cell.Reflection type polarizer has some advantages, for example can save the assembling of light source (for example back light source), and LCD is by further attenuation.

Reflection type polarizer can form in any known mode, for example forms the catoptron of being made by metal etc. on a surface of the polaroid with certain elasticity modulus.More particularly; an one example is by being delustered in a surface (surface of exposure) of polaroid protective clear layer as required; and deposit film is provided on this surface or comprises the metal forming of reflective metals (for example aluminium), and the reflection type polarizer that forms.

Another example of preparation reflection type polarizer is that described microscopic roughness obtains by comprise microparticle in different transparent resins by formation is corresponding to the catoptron of microscopic roughness on the protective clear layer that has microscopic roughness on the surface.Catoptron with microscopic roughness surface is the diffusion incident ray brokenly, to such an extent as to can prevent directivity and dazzle, and can control the irregularity of tone.Catoptron can by with any routine and suitable method on the rough surface of protective clear layer directly adhesion metal paper tinsel or metal deposited-film form, these methods comprise deposition (for example vacuum moulding machine) and evaporation (for example ion plating and sputter).

As mentioned above, catoptron can directly form on the protective clear layer of polaroid.Alternatively, also the reflector plate that forms by cremasteric reflex layer on the suitable film similar to protective clear layer can be used as catoptron.Because being used for the typical reflection horizon of catoptron is to be made of metal, thus preferably use the surface of film coated catoptron in use, to avoid because the reduction of the reflectivity that oxidation causes.In addition, initial reflectance is held for a long time, and avoids forming separately protective clear layer.

Provide translucent polaroid by the catoptron that replaces in the above-mentioned reflection type polarizer with translucent catoptron, the example comprises by the half-reflecting mirror at reflective layer reflects and transmitted ray.

Usually, this translucent polaroid is disposed in the back side of liquid crystal cell.In the LCD that comprises semitransparent reflector type polaroid, when under brighter environment, using LCD, its reflection is from the incident ray of viewable side (demonstration side), thereby display image, and in darker environment, come display image by using the built-in light source (for example back light source) on the semitransparent reflector type polaroid back side.In other words, the LCD that can use translucent polaroid to be formed on to save the energy of light source (for example back light source) under the bright light environments, and in darker environment, it can use built-in light source.

Describe below by a further example of the lamination polaroid for preparing of lamination brightness enhancing films on the polaroid with optical compensation function according to the present invention.

Suitable example to brightness enhancing films is not particularly limited, and it can be dielectric multilayer film; Or the multi-layer laminated films (for example, by " D-BEF " of 3M company production) with refraction ansiotropy of variation, its can linear propagation have the polarized light of predetermined polarisation axle, and reflects other light; Or cholesteric, more particularly, be (for example to be fixed to the oriented film of the cholesteric liquid crystal polymer on the support film substrate or aligned liquid-crystal layer, " PCF 350 " by Nitto Denki Corparation production, by Merck and Co., Inc. " Transmax " of Sheng Chaning), its clockwise or counterclockwise circularly polarized light of reflection and other light of transmission.

Above-mentioned various polaroids of the present invention can be to go back the optical element that lamination has additional optical layers on it for instance.

The optical element that comprises the laminate of at least two optical layers for instance can be by forming the method that each layer carries out lamination separately with the particular order of production LCD etc.But, because the optical element of lamination has excellent quality stability and assembling operability in advance, so can improve the efficient of production LCD.Suitable adhesive, for example pressure-sensitive adhesive layer can be used for lamination.

In addition, various polaroids preferably according to the present invention also have pressure-sensitive adhesive layer or bonding coat, it more easily is laminated on other element (for example liquid crystal cell).They can be disposed on the surface or two surfaces of polaroid.Material to pressure-sensitive adhesive layer is not particularly limited, and it can be conventional material known, for example acrylate copolymer.In addition, from preventing bending because of absorbing foaming that moisture causes or the deterioration of peeling off, prevent optical property and causing because of the difference of thermal expansivity, and the angle that forms the image display with high-quality and excellent durability considers that the pressure-sensitive adhesive layer with low humidity aspiration receipts coefficient and excellent heat resistance is preferred.Fine grained can also be added in the contact adhesive, show the pressure-sensitive adhesive layer of light diffusion characteristic with formation.In order on the surface of lamination retardation plate, to form pressure-sensitive adhesive layer, the solution or the molten mass of jointing material can be applied directly on the predetermined surface of polaroid by extended method (for example flow and sprawl and coating process) for instance.In addition, also can on following separation layer, form pressure-sensitive adhesive layer in an identical manner, it be transferred on the predetermined surface of polaroid then.This layer can form on any one side of polaroid.For instance, it can form on an exposure of the optical compensating layer of polaroid.

When needs expose the bonding coat be arranged on the polaroid or pressure-sensitive adhesive layer surperficial, preferably cover the surface of pressure-sensitive adhesive layer with separation layer, this can prevent that pressure-sensitive adhesive layer from being polluted before use.Can form separation layer by upward being coated with the peel ply that comprises remover (for example silicone base remover, chain alkyl remover, fluorocarbon remover or molybdenum sulfide) as required at suitable film (for example transparent membrane).

Pressure-sensitive adhesive layers etc. can be individual layer or laminate.Described laminate can comprise the individual layer that type or composition differ from one another.Two lip-deep pressure-sensitive adhesive layers that are arranged into polaroid can be mutually the same or different on type or composition.

The thickness of pressure-sensitive adhesive layer can wait suitably according to the component of polaroid to be determined.Usually, its thickness is from 1 to 500 micron.

Preferred pressure-sensitive adhesive layer is made by the contact adhesive with good optical property and adhesion characteristic (for example wettable, cohesiveness and cohesive).Contact adhesive can suitably prepare based on following polymers: for example acrylate copolymer, silicone-based polymer, polyester, polyurethane, polyethers, and synthetic rubber.

The cohesive of pressure-sensitive adhesive layer can be controlled by conventional known method.For instance, can be based on the content ratio of the composition of the raw polymer that forms contact adhesive or molecular weight, crosslink type, crosslinkable functionality, and the combined amount of crosslinking chemical, regulate degree of crosslinking and molecular weight.

As with ultraviolet absorber (for example salicylate compound, benzophenone cpd, benzotriazole cpd, alpha-cyanoacrylate ester compounds; and nickel complex salt compound) result of Chu Liing; lamination retardation plate of the present invention and lamination polaroid, and each element (for example optical anisotropic layer (A), optical anisotropic layer (B), polarizer, protective clear layer, optical layers and pressure-sensitive adhesive layer) of forming these plates all has ultraviolet absorption ability.

As mentioned above, lamination retardation plate of the present invention and lamination polaroid can be preferably used for forming various devices, for example LCD.For instance, lamination retardation plate of the present invention and lamination polaroid are positioned at least one surface of liquid crystal cell, thereby are formed on the liquid crystal board that uses in the LCD (for example transmission-type, reflection-type, perhaps transmission-reflection LCD).

The liquid crystal cell of forming LCD can be selected from following suitable element: for example be the active matrix driving (active matrix driving type) of representative with the thin film transistor (TFT), be the simple matrix driving (simple matrix driving type) of representative with twisted-nematic (twist nematic) type and supertwist to row (super twist nematic) type.Because the polaroid that has optical compensation function according to the present invention is being excellent especially aspect the optical compensation of VA (homeotropic alignment) element, so they particularly preferably are applicable to the compensation film for angular field of view of VA mode LCD.

Usually, typical liquid crystal cell is made up of relative liquid crystal cell substrate and the liquid crystal that is injected in the substrate gaps.The liquid crystal cell substrate can be made up of glass, plastics etc., and this is not particularly limited.The plastic material can be selected from conventional material known, and this is not particularly limited.

When polaroid or optical element were positioned on two surfaces of liquid crystal board, lamination retardation plate of the present invention and lamination polaroid were disposed at least one surface, and lamination retardation plate and lamination polaroid can be same types or dissimilar.In addition, when forming LCD, can go up in position and arrange one or more layers suitable element, for example prism array sheet, lens array plate, optical diffuser device and back light source.

LCD according to the present invention is not particularly limited, as long as it comprises liquid crystal board and uses liquid crystal board of the present invention.When it comprises light source,, be the dull light source (flatlight source) that can send polarized light in order to use luminous energy, preferred light source effectively although be not particularly limited.Comprise liquid crystal cell, lamination retardation plate of the present invention, polarizer and protective clear layer for instance according to liquid crystal board of the present invention; wherein; the lamination retardation plate is in turn laminated on the surface of liquid crystal cell, and polarizer and protective clear layer are laminated on another surface of lamination retardation plate successively.Liquid crystal is sandwiched between two liquid crystal cell substrates in described liquid crystal cell.The lamination retardation plate is the laminate of aforesaid optical anisotropic layer (A) and optical anisotropic layer (B), and its any side all can be faced polarizer.

LCD of the present invention can comprise add ons on the optical thin film (lamination polaroid) of viewable side.For instance, described element can be selected from diffusing panel, anti-dazzle tabula rasa, anti-reflective film, protective seam, and fender.Alternatively, compensating delay sheet etc. can suitably be placed between the liquid crystal cell and polaroid of liquid crystal board.

The polaroid that has optical compensation function according to the present invention not only can be used for above-mentioned LCD, and can be used for self-emitting display for instance, for example organic electroluminescent (EL) display, PDP and FED.When it was used for self-emitting display, in order to obtain circularly polarized light, length of delay Δ nd was set to λ/4 in the face of lamination retardation plate of the present invention and lamination polaroid, so it can be used for the antireflection filtrator for instance.

Be to comprise specifying of electroluminescence (EL) display that has the polaroid of optical compensation function according to the present invention below.EL display of the present invention is the display with lamination retardation plate of the present invention or lamination polaroid, and can be OLED display or inorganic EL display.

In present EL display,, advised using optical thin film (for example polarizer, polaroid and λ/4 plates) in order to prevent the reflection of electrode under dark state in the EL display.When sending linearly polarized photon, circularly polarized light or elliptic polarization light time from the EL layer, lamination retardation plate of the present invention and lamination polaroid are particularly useful.Even when under the situation of sending natural light on the frontal, and the oblique fire light beam is during by partial polarization, the polaroid that has optical compensation function according to the present invention also is particularly useful.

Explain typical OLED display at first, below.Usually, this OLED display has luminophor (organic EL luminophor), and it is by lamination of transparent electrode, organic luminorphor layer and metal electrode prepare successively on transparent substrates.At this, the organic luminorphor layer is the laminate of various organic films.Their example comprises various combinations, for example the laminate of hole injection layer of being made by triphenylamine derivative etc. and the emitter made by luminous organic solid (for example anthracene); The laminate of the electron injecting layer that emitter He You perylene derivant etc. is made; And the laminate of hole injection layer, emitter and electron injecting layer.

Usually, OLED display is luminous according to following principle: anode and negative electrode apply voltage, so that organic emitter is injected in hole and electronics, the energy excitation luminescent substance that produces by the recombination of these holes and electronics, and the luminescent substance that excites is luminous when returning ground state.To similar at general-purpose diode, these holes and electronics is compound again during this process.This shows that the relative voltage table that applies with luminous intensity of electric current reveals very big non-linearly, promptly is accompanied by rectification.

For OLED display, preferably at least one electrode is transparent, to obtain luminous at the organic luminorphor layer.Usually, the transparency electrode of being made by transparent conductive material (for example tin indium oxide (ITO)) is used to anode.Negative electrode helps electronics with the material with little work content and injects, thus and raising luminescence efficiency.Usually, can use metal electrode such as Mg-Ag and Al-Li as negative electrode.

In the OLED display of configuration as mentioned above, preferred organic emitter is made by the film of (for example about 10 nanometers) as thin as a wafer usually, so that the organic luminorphor layer can be basically with the whole light of the same transmission of transparency electrode.As a result, when this layer was not luminous, light beam was injected from transparent substrates, and passed transparency electrode and organic luminorphor layer, was spread out of once more on the surface of transparent substrates by metal layer reflection then.Thereby from the outside, the display surface of OLED display looks that to look like mirror the same.

The OLED display of organic EL luminophor that comprises according to the present invention has transparency electrode for instance on the surface of organic luminorphor layer, and has metal electrode at the organic luminorphor layer back side.In OLED display, preferably on the surface of transparency electrode, arrange lamination retardation plate of the present invention or lamination polaroid, in addition, between polaroid and EL element, arrange λ/4 plates.As mentioned above, by arranging that the OLED display that lamination retardation plate of the present invention and lamination polaroid obtain can suppress external reflection and improve its visuality.Further preferred retardation plate is positioned between transparency electrode and the optical thin film.

Retardation plate and polaroid etc. make the light generation polarization that enters from the outside and reflected by metal electrode for instance, therefore make that by polarization the minute surface with metal electrode can not seen from the outside.Especially, the minute surface of metal electrode can have the retardation plate of quarter wave plate by formation, and to regulate the angle that the polarization direction by retardation plate and polaroid forms be that cover fully π/4.That is to say that polaroid only spreads into the linear polarization light component in the extraneous light of OLED display.Usually, linearly polarized photon is delayed sheet and is transformed into elliptically polarized light.When retardation plate is quarter wave plate and angle when being π/4, light is transformed into circularly polarized light.

This circularly polarized light is for instance by transparent substrates, transparency electrode, and organic film.After by the metal electrode reflection, light passes through organic film, transparency electrode and transparent substrates once more, and is transformed into linearly polarized photon on retardation plate.In addition, because linearly polarized photon passes the polarization direction of polaroid with the right angle, so it can not pass through polaroid.Therefore, as mentioned above, the minute surface of metal electrode is covered fully.

(embodiment)

Further describe the present invention below with reference to embodiment and comparing embodiment.Should be understood that the present invention is not confined to these embodiment.Optical property and thickness are measured according to following mode.

(measurement of length of delay)

According to parallel-nicol (Nicol) rotary process, use postpones meter and (is produced trade name by Oji ScientificInstruments: KOBRA21-ADH) measure length of delay (measurement wavelength: 610 nanometers).

(film thickness measuring)

The DIGITAL MICROMETER-K-351C (trade name) that uses Anritsu to produce measures thickness.

(embodiment A-1)

At 175 ℃, stenter cross directional stretch thickness is 100 microns norborene film.Draw ratio is length before 1.4 times of stretchings on draw direction.Thus, acquisition thickness is 69 microns optical anisotropic layer (A), Re (A)=67 nanometer, Rth (A)=136 nanometer.By 2,2 '-two (3,4-dicarboxyl diphenyl) HFC-236fa and 2,2 '-two (trifluoromethyl)-4, the synthetic polyimide of 4 '-benzidine (weight-average molecular weight: 59,000) be dissolved in the cyclohexane, thereby prepare the polyimide solution of 15 weight %.After this polyimide solution being applied on the biaxial stretch-formed PET film, dry coating (temperature: 150 ℃, time: 5 minutes) is 3 microns a optical anisotropic layer (B) thereby form thickness on the PET of this stretching film.This optical anisotropic layer (B) has Re (B)=3 nanometer, Rth (B)=110 nanometer, and the optical property of Rth (B)/Re (B)=32.7.Then,, the optical anisotropic layer (B) on the stretching PET film is adhered to after optical anisotropic layer (A) goes up, peel off the PET film of stretching, obtain the lamination retardation plate at the acrylic pressure-sensitive layer that by thickness is 15 microns.

(embodiment A-2)

At 160 ℃, longitudinal stretching thickness is 70 microns mylar.Draw ratio is length before 1.1 times of stretchings on draw direction.Thus obtained optical anisotropic layer (A) thickness is 64 microns, Re (A)=65 nanometer, Rth (A)=70 nanometer, and Rth (A)/Re (A)=1.1.Then, go up directly coating by the polyimide solution of the preparation of the method in the embodiment A-1 at this optical anisotropic layer (A), and dry coating (temperature: 150 ℃, time: 5 minutes), form optical anisotropic layer (B) to go up, thereby produce the lamination retardation plate at optical anisotropic layer (A).Optical anisotropic layer (B) thickness is 5 microns, and optical property is: Re (B)=5 nanometer, Rth (B)=180 nanometer, and Rth (B)/Re (B)=36.0.After peeling off, measure the optical property of optical anisotropic layer (B) from optical anisotropic layer (A).

(embodiment A-3)

It is on 80 microns tri acetyl cellulose (TAC) film that the polyimide solution of preparation in the embodiment A-1 is applied to thickness, and accepts the stenter cross directional stretch, and under 180 ℃ temperature dry 5 minutes.Draw ratio is length before 2.0 times of stretchings on draw direction.As the result of this stretching, go up the optical anisotropic layer (B) that formation is made by polyimide at the TAC film (optical anisotropic layer (A)) that stretches, thereby obtain the lamination retardation plate.Optical anisotropic layer (A) thickness is 67 microns, and optical property is: Re (A)=30 nanometer, Rth (A)=55 nanometer, and Rth (A)/Re (A)=1.8.Optical anisotropic layer (B) thickness is 5 microns, and optical property is: Re (B)=40 nanometer, Rth (B)=198 nanometer, and Rth (B)/Re (B)=5.

(embodiment A-4)

By 4,4 '-two (3,4-dicarboxyl phenyl)-2,2-diphenyl propane dianhydride and 2,2 '-two chloro-4, the polyimide (weight-average molecular weight: 60 that 4 '-benzidine is synthetic, 000) is dissolved in the cyclopentanone, thereby prepares the polyimide solution of 20 weight %.It is on 80 microns the TAC film, to accept the stenter cross directional stretch that this polyimide solution is applied to thickness, and under 180 ℃ temperature dry 5 minutes.Draw ratio is length before 1.1 times of stretchings on draw direction.As the result of this stretching, go up the optical anisotropic layer (B) that formation is made by polyimide at the TAC film (optical anisotropic layer (A)) that stretches, thereby obtain the lamination retardation plate.Optical anisotropic layer (A) thickness is 74 microns, and optical property is: Re (A)=25 nanometer, Rth (A)=50 nanometer, and Rth (A)/Re (A)=2.Optical anisotropic layer (B) thickness is 6 microns, and optical property is: Re (B)=38 nanometer, Rth (B)=220 nanometer, and Rth (B)/Re (B)=44.

(Comparative Example A An-1)

At 175 ℃, stenter cross directional stretch thickness is 100 microns norborene film.Draw ratio is length before 1.8 times of stretchings on draw direction.Thus obtained optical anisotropic layer (A) thickness is 88 microns, Re (A)=252 nanometer, Rth (A)=252 nanometer and Rth (A)/Re (A)=1.0.Similarly, thickness be 100 microns norborene film be stretched to stretch before 1.5 times of length, be 95 microns optical anisotropic layer (B) to obtain thickness, Re (B)=180 nanometer, Rth (B)=181 nanometer, and Rth (B)/Re (B)=1.0.Then, on optical anisotropic layer (A), use thickness and be 15 microns acrylic pressure-sensitive layer, and optical anisotropic layer (A) and optical anisotropic layer (B) be bonded to each other, and made that slow axis intersects mutually with the right angle in separately the face.Thus, produce lamination retardation plate (nx＞ny＞nz).

For the lamination retardation plate that obtains to A-4 and the Comparative Example A An-1 in embodiment A-1, measure length of delay (Re) and thickness direction retardation value (Rth) in thickness, the face.The results are shown in Table 1.

Table 1

	Optical anisotropic layer (A)				Optical anisotropic layer (B)				The lamination retardation plate
														d(A) μm	Re(A) nm	Rth(A) nm	Rth(A) /Re(A)	d(B) μm	Re(B) nm	Rth(B) nm	Rth(B) /Re(B)	d μm	Re nm	Rth nm	Rth-Re nm
A-1 A-2 A-3 A-4	69 64 67 74	67 65 30 25	136 70 55 50	2.9 1.1 1.8 2.0	3 5 5 6	3 5 40 38	110 180 198 220	32.7 36.0 5.0 44.0	87 69 72 80	71 68 70 63	248 252 253 270	177 184 183 207
													A-1 *	88	252	252	1.0	95	180	181	1.0	183	72	252	180

Annotate: A-1, A-2, A-3, A-4=embodiment A-1 are to A-4; A-1 ^*=Comparative Example A An-1

As shown in table 1, for the lamination retardation plate that uses the norborene film as the comparing embodiment 1 of optical anisotropic layer (B), in order to obtain the optical property comparable with other embodiment, thickness must be increased to 183 microns.On the other hand, the lamination retardation plate for each embodiment that polyimide is used for optical anisotropic layer (B) has not only obtained enough optical properties, and film thickness be reduced to thickness in the Comparative Example A An-1 pact half.

(Embodiment B)

The lamination polaroid of production shown in Fig. 1-8.In these figure, components identical is represented with identical mark.

(Embodiment B-1)

In the present embodiment, production lamination polaroid 10 as shown in Figure 1.At first, at 180 ℃ of following longitudinal stretching thickness be 100 microns norborene film.Draw ratio is length before 1.2 times of stretchings on draw direction.Thus, acquisition thickness is 90 microns optical anisotropic layer (A) 11a.By 2,2 '-two (3,4-dicarboxyl diphenyl) HFC-236fa and 2,2 '-two (trifluoromethyl)-4, the synthetic polyimide of 4 '-benzidine (weight-average molecular weight: 59,000) be dissolved in the cyclohexane, thereby prepare the polyimide solution of 15 weight %.After this polyimide solution being applied on the biaxial stretch-formed PET film, dry coating (temperature: 150 ℃, time: 5 minutes) is 5 microns optical anisotropic layer (B) 11b thereby form thickness on the PET of this stretching film.Then, at the acrylic pressure-sensitive layer 14 that by thickness is 15 microns, with optical anisotropic layer (B) 11b on the stretching PET film adhere to optical anisotropic layer (A) 11a last after, peel off the PET film of stretching, be 110 microns lamination retardation plate 11 thereby obtain thickness.

In addition, in the aqueous solution of iodine, be 5 times that 80 microns polyvinyl alcohol (PVA) (PVA) film is stretched to original length with thickness, drying obtains polarization layer 13 then.Then, it by thickness 15 microns acrylic pressure-sensitive layer 14, with thickness is that 80 microns TAC film 12 adheres on the surface of polarization layer 13, and lamination retardation plate 11 is adhered on another surface, and make optical anisotropic layer (A) 11a towards polarization layer 13, thereby acquisition thickness is 240 microns wide visual angle lamination polaroid 10.

(Embodiment B-2)

In the present embodiment, production lamination polaroid 20 as shown in Figure 2.Except lamination retardation plate 11 is adhered on the polarization layer, and make optical anisotropic layer (B) 11b beyond polarization layer 13,, obtain thickness and be 240 microns wide visual angle lamination polaroid 20 according to the mode identical with Embodiment B-1.

(Embodiment B-3)

In the present embodiment, production lamination polaroid 30 as shown in Figure 3.Under 180 ℃, stenter stretching thickness is 70 microns mylar (draw ratio: 1.2), thereby obtain optical anisotropic layer (A) 11a of 59 microns of thickness on draw direction.Then, will according to Embodiment B-1 in the polyimide solution of same way as preparation be applied on optical anisotropic layer (A) 11a, dry then (temperature: 150 ℃, time: 5 minutes) is 3 microns optical anisotropic layer (B) 11b thereby form thickness.Make thickness as the laminate of optical anisotropic layer (A) 11a and optical anisotropic layer (B) 11b thus and be 62 microns lamination retardation plate 31.Then, it by thickness 15 microns acrylic pressure-sensitive layer 14, with thickness is that 80 microns TAC film 12 adheres on the surface as the polarization layer 13 that obtains among the embodiment 1, and lamination retardation plate 31 is adhered on another surface, and make optical anisotropic layer (A) 11a towards polarization layer 13, thereby acquisition thickness is 192 microns wide visual angle lamination polaroid 30.

(Embodiment B-4)

In the present embodiment, production lamination polaroid 40 as shown in Figure 4.Except lamination retardation plate 31 is adhered on the polarization layer 13, and make optical anisotropic layer (B) 11b beyond polarization layer 13, according to the mode identical with Embodiment B-3, acquisition thickness is 192 microns wide visual angle lamination polaroid 40.

(Embodiment B-5)

In the present embodiment, production lamination polaroid 50 as shown in Figure 5.Will by with Embodiment B-1 in the polyimide solution of same way as preparation to be applied to thickness be on 80 microns the TAC film, then it is stood the stenter cross directional stretch, draw ratio is 1.3, and under 190 ℃ temperature dry 5 minutes.The gross thickness of thus obtained lamination retardation plate 31 is 66 microns, and it comprises that thickness on the stretching TAC film (optical anisotropic layer (A) 11a) that is laminated to 60 microns of thickness is 6 microns Kapton (optical anisotropic layer (B) 11b).Then, it by thickness 5 microns PVA base bonding coat 15, with thickness is that 80 microns TAC film 12 adheres on the surface as the polarization layer 13 that obtains among the embodiment 1, and lamination retardation plate 31 is adhered on another surface, and make optical anisotropic layer (A) 11a towards polarization layer 13, thereby acquisition thickness is 183 microns wide visual angle lamination polaroid 176.

(Embodiment B-6)

In the present embodiment, production lamination polaroid 60 as shown in Figure 6.Except lamination retardation plate 31 is adhered on the polarization layer 13, and make optical anisotropic layer (B) 11b beyond polarization layer 13,, obtain thickness and be 176 microns wide visual angle lamination polaroid 60 according to the mode identical with Embodiment B-5.

(Embodiment B-7)

In the present embodiment, production lamination polaroid 70 as shown in Figure 7.Under 190 ℃, stenter stretching TAC film, draw ratio is 1.4, thereby obtains optical anisotropic layer (A) 11a of 69 microns of thickness.Then, it by thickness 5 microns PVA base bonding coat 15, be respectively that 80 microns TAC film 12 adheres on the surface as the polarization layer 13 that obtains among the embodiment B-1 with thickness, optical anisotropic layer (A) 11a is adhered on polarization layer 13 another surfaces.In addition, by thickness is 15 microns acrylic pressure-sensitive layer 14, will be laminated to as optical anisotropic layer (B) 11b that obtains among the embodiment B-1 on optical anisotropic layer (A) 11a, subsequently, peel off the PET film of stretching, acquisition thickness is 199 microns wide visual angle lamination polaroid 70.

(Embodiment B-8)

In the present embodiment, production lamination polaroid 80 as shown in Figure 8.Will be by 4,4 '-two (3,4-dicarboxyl phenyl)-2,2-diphenyl propane dianhydride and 2,2 '-two chloro-4, the polyimide (weight-average molecular weight: 65 that 4 '-benzidine is synthetic, 000) is dissolved in the cyclopentanone, thereby prepares the polyimide solution of 20 weight %.It is on 80 microns the TAC film, to accept the stenter cross directional stretch that this polyimide solution is applied to thickness, and under 200 ℃ temperature dry 5 minutes.Draw ratio is length before 1.5 times of stretchings on draw direction.Thus obtained lamination retardation plate integral thickness is 60 microns, and it comprises that thickness on the stretching TAC film (optical anisotropic layer (A)) that is laminated to 54 microns of thickness is 6 microns Kapton (optical anisotropic layer (B)).Then, by the basic pressure-sensitive adhesive layer 15 of polyvinyl alcohol (PVA) (PVA), the lamination retardation plate is adhered on the surface as the polarization layer that obtains among the embodiment B-1, and make optical anisotropic layer (A) towards polarization layer, relending and helping PVA base bonding coat is that 80 microns TAC film 12 adheres on another surface of polarization layer with thickness.Thereby acquisition thickness is 170 microns wide visual angle lamination polaroid.

(Comparative Examples B-1)

With thickness is 60 microns, Re (A)=0.9 nanometer, and the TAC film of Rth (A)=59 nanometer and Rth (A)/Re (A)=66 is as optical anisotropic layer (A).Coating in the above is as the polyimide solution among the embodiment B-1, and 130 ℃ dry 5 minutes down, go up formation optical anisotropic layer (B) at optical anisotropic layer (A), thereby to produce thickness be 85 microns and show the lamination retardation plate of nz ≈ ny＞nz.In addition, it by thickness 5 microns the basic pressure-sensitive adhesive layer of polyvinyl alcohol (PVA) (PVA), the lamination retardation plate is adhered on the surface as the polarization layer that obtains among the embodiment B-1, and make optical anisotropic layer (A) towards polarization layer, relending and helping PVA base bonding coat (thickness: 5 microns) is that 80 microns TAC film adheres on another surface of polarization layer with thickness.Thereby acquisition thickness is 170 microns wide visual angle lamination polaroid.

(Comparative Examples B-2)

To be applied on the mylar as the polyimide solution among the embodiment B-1, and 130 ℃ dry 5 minutes down, again at the draw ratio of 160 ℃ of following stenter cross directional stretchs to 1.1.Remove mylar, obtain the optical anisotropic layer of making by polyimide (B).This optical anisotropic layer (B) has 6 microns thickness, Re (B)=55 nanometer, Rth (B)=240 nanometer and Rth (B)/Re (B)=4.4.It by thickness 5 microns the basic pressure-sensitive adhesive layer 15 of polyvinyl alcohol (PVA) (PVA), adhere to optical anisotropic layer (A) on the surface of the polarization layer that in as embodiment B-1, obtains, relending and help acrylic pressure-sensitive adhesive (thickness: 15 microns), is that 80 microns TAC film adheres on another surface of polarization layer with thickness.Thereby acquisition does not comprise the wide visual angle lamination polaroid of optical anisotropic layer (A).

(Comparative Examples B-3)

Under 190 ℃, thickness is that 80 microns TAC film is accepted stenter cross directional stretch to 1.4 times, thereby obtains to have 58 microns thickness, Re (A)=40 nanometer, the optical anisotropic layer (A) of Rth (A)=46 nanometer and Rth (A)/Re (A)=1.2.To be applied to as the polyimide solution of embodiment B-1 on the mylar, and it is following dry 5 minutes at 130 ℃, under 160 ℃, accept free end again and be longitudinally stretched to 1.2 times of initial length, thereby on mylar, form the optical anisotropic layer of making by polyimide (B).This optical anisotropic layer (B) has 6 microns thickness, Re (B)=170 nanometer, Rth (B)=200 nanometer and Rth (B)/Re (B)=1.2.By thickness is 15 microns acrylic pressure-sensitive adhesive, goes up at optical anisotropic layer (B) and adheres to optical anisotropic layer (A), and these layers are faced with each other, and removes mylar then, obtains the lamination retardation plate.It is 210 nanometers that this lamination retardation plate has 64 microns thickness, Re, and Rth is 246 nanometers, and Rth/Re is 1.2, and (Rth-Re) is 36 nanometers.The lamination retardation plate is adhered on the surface as the polarization layer that obtains among the embodiment B-1, and make optical anisotropic layer (A) towards polarization layer, relending and helping PVA base bonding coat (thickness: 5 microns) is that 80 microns TAC film adheres on another surface of polarization layer with thickness.Thereby acquisition thickness is 189 microns wide visual angle lamination polaroid.

(Comparative Examples B-4)

According to the mode identical, obtain polarization layer with Embodiment B-1.

To the optical anisotropic layer (A), optical anisotropic layer (B) and the lamination retardation plate that obtain in to B-8 and Comparative Examples B-1 to B-3 in Embodiment B-1, method is measured length of delay, thickness direction retardation value etc. in the face respectively as described above.The results are shown in the following table 2.

Table 2

	Optical anisotropic layer (A)				Optical anisotropic layer (B)				The lamination retardation plate
														d(A) μm	Re(A) nm	Rth(A) nm	Rth(A) /Re(A)	d(B) μm	Re(B) nm	Rth(B) nm	Rth(B) /Re(B)	d μm	Re nm	Rth nm	Rth-Re nm
B-1 B-2 B-3 B-4 B-5 B-6 B-7 B-8	90 90 59 59 60 60 58 54	50 50 50 50 30 30 40 33	52 52 144 144 38 38 46 36	1.0 1.0 2.9 2.9 1.3 1.3 1.2 1.1	5 5 3 3 6 6 5 6	5 5 4 4 22 22 5 25	180 180 91 91 200 200 180 205	36.0 36.0 22.8 22.8 9.1 9.1 36.0 8.2	95 95 72 72 66 66 78 60	55 55 54 54 52 52 45 59	232 232 235 235 238 238 226 240	177 177 181 181 186 186 181 181
													B-1 * B-2 * B-3 *	80 - 58	0.9 - 10	59 - 46	66 - 1.2	5 6 6	0.3 55 170	170 240 200	567 4.4 1.2	85 - 64	1 55 210	229 240 246	228 185 36

Annotate: B-1 ... B-8=Embodiment B-1 is to B-8; B-1 ^*B-3 ^*=Comparative Examples B-1 is to B-3

The wide visual angle lamination polaroid that Embodiment B-1 is obtained in to B-8 and Comparative Examples B-1 to B-3, and the viewing angle characteristic of the polaroid that obtains in the Comparative Examples B-4 is estimated.Polaroid is disposed on two surfaces of VA type liquid crystal cell, and the axis of homology that makes them is each other with right angle intersection.Arrange the wide visual angle polaroid among each embodiment, make the lamination retardation plate towards liquid crystal cell.In this state, measure viewing angle characteristic, it provides 10 or bigger Co (contrast) on the display screen of LCD.

Contrast is calculated in the following manner.Display white image and black image on LCD, thereby use instrument (" Ez contrast 160D " (trade name) that ELDIM SA produces) in the front of display, vertical, level, 45 ° to-225 ° diagonal line, and Y, x and the y value of measured X YZ display system on 135 ° to-315 ° the diagonal.Y value (Y based on white image _W) and the Y value (Y of black image _B), calculate the contrast ratio (Y at each visual angle _W/ Y _B).Similarly, measure the visual angle contrast ratio of the LCD (wherein do not use the lamination retardation plate, and only encapsulate polaroid) in the Comparative Examples B-1.Below table 3 expression provide 10 or the angular field of view of bigger contrast.In addition, the display screen of each LCD of visual inspection, thus estimate the painted of lamination retardation plate.The result also lists in the following table 3.

Table 3

	The visual angle (°)				Painted
						Vertically	Level	Diagonal angle (45-225)	Diagonal angle (135-315)
	Embodiment B-1 Embodiment B-2 Embodiment B-3 Embodiment B-4 Embodiment B-5 Embodiment B-6 Embodiment B-7 Comparative Examples B-1 Comparative Examples B-2 Comparative Examples B-3 Comparative Examples B-4	±80 ±80 ±80 ±80 ±80 ±80 ±80 ±80 ±80 ±80 ±80	±80 ±80 ±80 ±80 ±80 ±80 ±80 ±80 ±80 ±80 ±80	±65 ±65 ±60 ±60 ±65 ±65 ±60 ±40 ±55 ±40 ±35	±65 ±65 ±60 ±60 ±65 ±65 ±60 ±40 ±55 ±40 ±35						Whether no is

The lamination polaroid that comprises lamination retardation plate of the present invention shown in the use table 2 obtains the LCD that each comparing embodiment is wider than at the visual angle, and is as shown in table 3.In comparing embodiment 1, because optical anisotropic layer (A) postpones in the complementary area fully, so postpone (Re) in the face less than 10 nanometers.In Comparative Examples B-3, because (Rth-Re) less than 50 nanometers, so the viewing angle characteristic variation at diagonal angle.In Comparative Examples B-3, can see painted.Only using in the Comparative Examples B-2 of the optical anisotropic layer of being made by polyimide (B), the viewing angle characteristic at diagonal angle is not as good in the embodiment of the invention.In addition, increased thickness direction retardation because only using optical anisotropic layer (B), so can see painted.These facts show that use can provide the high definition LCD of and visual excellence thinner than traditional devices according to wide visual angle of the present invention lamination polaroid.

Industrial applicability

As mentioned above, because have excellent wide angle viewing angle characteristic, and when being used for various image display, reduced thickness, so Re is 10 nanometers and (Rth-Re) is that 50 nanometers or bigger lamination retardation plate of the present invention are very useful.

Claims (5)

1, a kind of manufacture method that comprises the lamination retardation plate of two-layer at least optical anisotropic layer, described lamination retardation plate comprises optical anisotropic layer of being made by polymkeric substance (A) and the optical anisotropic layer of being made by at least a non-liquid crystal polymer that is selected from polyamide, polyimide, polyester, polyaryletherketone, polyetherketone, polyamidoimide and the polyester-imide (B)

Wherein postpone (Re) in the face of representing by equation and be not less than 10nm, and

Thickness direction retardation (Rth) and the interior difference (Rth-Re) that postpones between (Re) of face represented by equation are 50 nanometers or bigger,

The manufacture method of described lamination retardation plate is characterised in that, on the described optical anisotropic layer of making by polymkeric substance (A), be coated with described non-liquid-crystalline polymer solution and form coating, dry described coating, described optical anisotropic layer (A) and the described coating that stretches indirectly only stretch simultaneously, form described optical anisotropic layer (B) thus

Re＝(nx-ny)·d

Rth＝(nx-nz)·d

In the formula, nx, ny, nz represent the refractive index on X-direction, Y direction and the Z-direction in the described lamination retardation plate respectively; Described X-direction be in the described lamination retardation plate plane refractive index maximum axially, described Y direction be in this plane perpendicular to described X-axis axially, and described Z-direction is perpendicular to the thickness direction of described X-axis and Y-axis; And d represents the thickness of described lamination retardation plate.

2, according to the manufacture method of the lamination retardation plate of claim 1, use substrate to replace described optical anisotropic layer (A), in described substrate, be coated with described non-liquid-crystalline polymer solution and form coating, dry described coating, simultaneously only stretch described substrate and the described coating that stretches indirectly forms described optical anisotropic layer (B) thus, described optical anisotropic layer (B) is adhered on the described optical anisotropic layer (A), then, peel off described substrate.

3, according to the manufacture method of the lamination retardation plate of claim 1, the formation material of described optical anisotropic layer (A) is made by the polymkeric substance that shows positive birefringence.

4, according to the manufacture method of the lamination retardation plate of claim 1, described lamination retardation plate satisfies nx＞ny＞nz.

5, the manufacture method of the lamination retardation plate of putting down in writing according to claim 1, in described lamination retardation plate, further lamination pressure-sensitive adhesive layer at least one outermost layer.

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