JP2007219022A - Roll-shaped retardation film and elliptically polarizing plate, and method for manufacturing them - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a roll-shaped continuously laminated retardation film which is manufactured with a simple method, has excellent productivity and causes little loss of an optical film, and a method for manufacturing it, and also to provide an elliptically polarizing plate using the same, and a method for manufacturing the elliptically polarizing plate. <P>SOLUTION: The roll-shaped continuously laminated retardation film includes sheets continuously taken out from a roll-shaped retardation film of which the slow axis is substantially parallel to its longitudinal direction, and which is cut in such a way that at least an edge of a quadrangle forms a predetermined angle with the slow axis of the film, and continuously laminated to a roll-shaped adhesive film for transportation in such a way that the slow axes of the sheets form a predetermined angle with the longitudinal direction of the film. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a roll-like retardation film continuous laminated film, a production method thereof, an elliptically polarizing plate using the same, and a production method thereof.

  An elliptically polarizing plate used for a liquid crystal display device or the like is configured by laminating a polarizing plate and a retardation film. That is, the polarizing plate and the retardation film are bonded using an adhesive or an adhesive so that the absorption axis of the polarizing plate and the slow axis of the retardation film form a predetermined angle.

  In recent years, liquid crystal display devices are widely used not only in word processors and personal computer screens but also in small electronic devices such as automobile navigation systems, mobile phones, and PDAs. The market demand for downsizing, thinning, and weight reduction is increasing year by year, and accompanying this, there is an increasing demand for making the elliptically polarizing plate thinner than before. In addition, the reduction in thickness is advantageous in that the flexibility is considerably improved.

  From the background as described above, proposals have conventionally been made to make the polarizing plate thinner. For example, a protective film used for a polarizing plate is thinned, and Patent Document 1 proposes a polarizing plate having a structure in which a protective film for a polarizing plate is attached to only one side. Further, not only the polarizing plate but also the elliptical polarizing plate can be thinned by reducing the thickness of the adhesive layer.

  However, the thinning of the polarizing plate deteriorates the dimensional stability, and there is a problem that the dimensional change due to expansion and contraction becomes large particularly under heat or wet heat conditions. Therefore, foaming, film floating, peeling, and the like are likely to occur in the adhesive layer. Further, foaming, floating, peeling and the like are likely to occur even when the adhesive layer is thinned. This is particularly noticeable in the case of lamination with an adhesive.

  As described above, there is a demand from the market for thin polarizing plates that can meet the demands for thin elliptical polarizing plates, and adhesives or adhesives that can be thinned that are unlikely to foam, float, and peel. .

  On the other hand, the demand for quality improvement and price reduction from the market is increasing year by year. Therefore, when manufacturing an elliptically polarizing plate, there are major issues such as improving the accuracy of the lamination angle, continuation of the lamination process, improving the yield, and reducing material loss.

  Patent Document 2 discloses a method in which a polarizing plate and a sheet of retardation film are bonded by adjusting the angle so as to be a predetermined angle, and an edge of the obtained laminate is cut to form an elliptically polarizing plate. Has been proposed.

  However, in the above method, it is necessary to separately perform the three steps of the polarizing plate cutting step, the retardation film cutting step, and the polarizing plate and retardation film bonding step, which complicates the work steps and increases the work steps. There was also a lot of loss that led to increased costs.

  In Patent Document 3, a long sheet of either a polarizing plate or a retardation film is cut so as to have a predetermined angle with respect to the optical axis to obtain a sheet, There has been proposed a method of manufacturing an elliptically polarizing plate by continuously laminating the optical axes so as to form a predetermined angle θ.

  However, the above-described method has a problem that the production capacity does not increase because it is necessary to bond the sheet of the other optical film to the roll-shaped optical film with accurate angle control. Further, when the angle is shifted, both the polarizing plate and the retardation film are defective, leading to a significant cost increase. Furthermore, in the case of the above production method, lamination with a pressure-sensitive adhesive is possible, but lamination with an adhesive has a problem in that the optical film sheet is displaced because the adhesive before curing is liquid.

  In Patent Document 4, a retardation film stretched in a cylindrical shape is continuously cut at a predetermined angle with respect to the stretching direction to obtain a long retardation film, and a transparent film obtained by stretching it in the longitudinal direction A manufacturing method has been proposed in which layers are laminated and bonded together.

  However, the above method requires a cylindrical film manufacturing machine (blow molding machine), and continuous cutting of a cylindrical stretched film at a predetermined angle makes it difficult to accurately cut the roll film. The process is more complicated than the retardation film produced by stretching, and the cost is considerably increased, which is not practical.

  In Patent Document 5, a long polarizing plate is cut into a bias shape so as to be at a predetermined angle with respect to the longitudinal direction (optical axis), and the bias cutting plate is replaced so that the cutting edge is a vertical line. A method of joining in state has been proposed.

  However, the above method requires a step of joining the biased cutting plates, and the production capacity does not increase, and when laminated with a retardation film, the angle control accuracy is low and the yield is low, leading to a significant cost increase. In addition, since the parts to be joined are joined with, for example, an adhesive tape, a problem that the part is lost at the time of product, a step due to the adhesive tape occurs at the joint part, and causes of poor bonding with the polarizing plate There was a problem of becoming.

  In Patent Document 6, from either one of the elongated material of the polarizing plate and the retardation film, the rectangular adjacent material is cut so that each of the two adjacent sides of the rectangle has a predetermined angle with the stretching axis, The rectangular object is continuously fixed to a long carrier film, and the long object of the other film is bonded to the rectangular object on the carrier film and cut into a predetermined shape. A method of manufacturing an elliptically polarizing plate has been proposed.

  However, in the above method, each of the two adjacent sides of the rectangle is cut so as to have a predetermined angle with respect to the extending axis, and the rectangular sheet is taken out. As a result, it is a loss of an expensive optical film, which leads to a considerable cost increase.

JP 2001-108830 A JP 4-123008 A Japanese Patent Laid-Open No. 10-206631 JP-A-55-59407 JP-A-6-289221 JP-A-6-300918

  The present invention has been achieved as a result of studying the solution of the above-described problems in the prior art as a subject, a highly efficient roll-like retardation film continuous laminated film, a production method thereof, and an elliptically polarizing plate using the same, and It aims at providing the manufacturing method.

  Accordingly, the present inventors have conducted extensive research to solve such problems, and as a result, a roll-like retardation film whose slow axis or fast axis (hereinafter simply referred to as slow axis) is substantially parallel to the longitudinal direction. To cut out at least one side of the parallelogram or trapezoid so that at least one side of the parallelogram or trapezoid has a predetermined angle (0 ° <θ <180 °) with respect to the slow axis of the film. Is bonded to a roll-like pressure-sensitive adhesive film continuously so that the slow axis of the sheet body becomes a predetermined angle (0 ° <θ <180 °) with respect to the longitudinal direction of the film. A roll-like retardation film continuous bonding film having a phase axis having a predetermined angle (0 ° <θ <180 °) with respect to the longitudinal direction is manufactured, and the retardation film continuous bonding film and an absorption axis or transmission axis A roll whose (hereinafter simply referred to as absorption axis) is substantially parallel to the longitudinal direction. It is found that a roll-shaped elliptically polarizing plate can be manufactured by bonding the linearly polarizing plates so that their longitudinal directions are substantially parallel to each other. The present inventors have found that a polarizing plate can be produced relatively easily in the process with little material loss, and the present invention has been completed.

  Further, according to the examination results of the inventors, in the production of the elliptically polarizing plate by the above method, a curable adhesive that is cured and bonded by irradiation of heat or active energy rays when the polarizing plate and the retardation film are bonded. It has been found that it is effective to use. That is, the polarizing plate and the retardation film are fixed by a curable adhesive that adheres firmly, and the dimensional change under heat or wet heat conditions is suppressed to prevent foaming, floating, peeling, and the like.

  According to the present invention, as will be described below, it is possible to manufacture a laminated body laminated at a bonding angle other than 0 degrees with high accuracy, at high speed, simply and continuously with high productivity.

  According to the present invention, at least one side of a quadrilateral has a predetermined angle (0 ° <θ <180 °) with respect to the slow axis of the film from a roll-like retardation film whose slow axis is substantially parallel to the longitudinal direction. The sheet is continuously taken out, and the sheet is taken into a roll-like adhesive film for conveyance, and the slow axis of the sheet is relative to the longitudinal direction of the film at a predetermined angle (0 ° <θ By laminating continuously such that <180 °), a roll-like retardation film having a slow axis or a fast axis having a predetermined angle (0 ° <θ <180 °) with respect to the longitudinal direction is obtained. The present invention relates to a retardation film continuous bonding film (hereinafter referred to as a first invention), which is a film bonded continuously, and in which the rectangular sheet is a parallelogram or trapezoid.

Various types of retardation films can be used. Optical films that have been processed such as uniaxial or biaxial stretching, or liquid crystal compounds are applied to a substrate and processed for orientation and fixation. An optical film or the like is used, and the magnitude relationship (refractive index ellipsoid) of the three-dimensional refractive index is controlled in accordance with the use conditions. It is mainly used to compensate for coloration of the liquid crystal layer of a liquid crystal display and to compensate for changes in phase difference due to viewing angle.
As a specific example of the retardation film, as an optical film material subjected to processing such as stretching, polyolefin such as polyethylene, polypropylene, cyclic polyolefin, polycarbonate, polyvinyl alcohol, polystyrene, polymethyl methacrylate, polyarylate, Examples thereof include polyamide. In addition, “WV film” (manufactured by Fuji Photo Film Co., Ltd.), “LC film”, “NH film” can be used as optical films that are prepared by applying a liquid crystalline compound or the like to a substrate and then processing the alignment and fixation. (Both made by Nippon Oil Corporation).

One embodiment of the first invention will be described with reference to FIGS.
First, as shown in FIG. 1, a roll-like retardation film (11) whose slow axis (12) is substantially parallel to the longitudinal direction is cut into a rectangular sheet (13) and continuously taken out.
This rectangular sheet has parallel sides ad and bc and non-parallel sides ab and cd with respect to the slow axis (12), and at least one side of the sides ab and cd is on the slow axis of the film. On the other hand, it has a predetermined angle (0 ° <θ <180 °). The rectangular sheet (13) is a parallelogram or trapezoid.

  Next, as shown in FIG. 2, the obtained retardation film sheet (22) is transferred to a roll-like pressure-sensitive adhesive film (21) for the slow phase of the sheet relative to the longitudinal direction of the film. The slow axis (23) has a predetermined angle (0 ° <θ <180) with respect to the longitudinal direction by continuously bonding the axis (23) so as to be a predetermined angle (0 ° <θ <180 °). A roll-like retardation film continuous laminated film (24) having (°) is obtained. At this time, at least one side of the retardation film sheet (22) is substantially parallel to the long side of the roll-shaped transport adhesive film (21).

As a conveyance adhesive film, it is a film which has a releasable adhesion layer in the one side or both sides of a film, and is also called a carrier film, a tape for conveyance, etc.
Examples of the film include olefinic films such as polyethylene and polypropylene, and polyester films such as polyethylene terephthalate.
Although there is no limitation in particular in the adhesive film for conveyance used by this invention, you have to select suitably by adhesive strength with retardation film, the presence or absence of the adhesive residue when peeling a retardation film, etc.

The retardation film continuous laminated film obtained by 1st invention can be preferably used for manufacture of an elliptically polarizing plate.
The elliptically polarizing plate is usually configured by laminating a polarizing plate and a retardation film. That is, the polarizing plate and the retardation film are bonded using an adhesive or an adhesive so that the absorption axis of the polarizing plate and the slow axis of the retardation film form a predetermined angle.

  In the second invention of the present invention, the roll-shaped linearly polarizing plate whose absorption axis is substantially parallel to the longitudinal direction, and the roll-shaped retardation film continuous laminated film obtained in the first invention, the mutual longitudinal directions are The present invention relates to a roll-shaped elliptically polarizing plate bonded to be substantially parallel to form a roll-shaped elliptically polarizing plate.

As the polarizing plate, various types of polarizing plates can be used as long as they have a function of selectively transmitting a certain direction of linearly polarized light from a non-polarized light beam.
For example, an iodine polarizing film in which iodine is adsorbed and oriented on a polyvinyl alcohol film, a dye polarizing film in which a dichroic dye is adsorbed and oriented on a polyvinyl alcohol film, a vinyl alcohol / polyene polarizing film, ( (Lyotropic) Coating type polarizers coated with a dichroic dye in a liquid crystal state, oriented and fixed.
These iodine-based polarizing films, dye-based polarizing films, vinyl alcohol / polyene-based polarizing films, and coated polarizing plates selectively transmit one direction of linearly polarized light from natural light and absorb the other direction of linearly polarized light. It has a function to perform, and is called an absorption type polarizing plate.
The iodine-based polarizing film and the dye-based polarizing film are usually formed as a polarizing plate by providing a protective layer on one or both sides. In a polarizing plate provided with a protective layer only on one side, the surface to be bonded to the surface light source element may be a surface with a protective layer or a surface without a protective layer.
Examples of the protective layer include cellulose acetate resin films such as triacetyl cellulose and diacetyl cellulose, acrylic resin films, polyester resin films, polyarylate resin films, polyether sulfone resin films, and cyclic olefins such as norbornene as monomers. The thing which bonded the cyclic polyolefin resin film etc. to do is mentioned. The protective layer is not limited to a film. For example, it may be a protective layer formed by coating.
The polarizing plate used in the present invention is not limited to the absorptive polarizing plate described above, but is also a reflective polarized light having a function of selectively transmitting one direction of linearly polarized light from natural light and reflecting or scattering the other direction of linearly polarized light. What is called a board and a scattering type polarizing plate may be used. Moreover, the polarizing plate specifically mentioned above is not necessarily limited by these, What is necessary is just to have a function which selectively permeate | transmits one direction of linearly polarized light from natural light.
Among these polarizers, the polarizing plate used for the elliptically polarizing plate is preferably an absorptive polarizing plate that is excellent in visibility, and among them, iodine-based polarized light having excellent polarization degree and transmittance. Most preferably, a plate is used.

Any adhesive may be used as long as it is excellent in adhesiveness and does not adversely affect the optical characteristics of the elliptically polarizing plate.
Specifically, (meth) acrylate type, oxetane type monomer / oligomer type adhesives, urea resin type, melamine resin type, phenol resin type, resorcinol resin type, epoxy type, polyurethane resin type, vinyl acetate resin type, Resin adhesives such as polyvinyl alcohol resin, acrylic resin, cellulose resin, chloroprene, nitrile rubber, styrene butadiene rubber, styrene block copolymer thermoplastic elastomer, butyl rubber, natural rubber, recycled rubber , Rubber adhesives such as chlorinated rubber and silicone rubber, and natural adhesives such as glue and starch.

  The adhesive can be cured by irradiation with active energy rays, heating, or both to firmly bond the polarizing plate and the retardation film.

When curing is performed by irradiation with active energy rays, the light source used is not particularly limited. For example, a low pressure mercury lamp, a medium pressure mercury lamp, a high pressure mercury lamp, an ultrahigh pressure mercury lamp, a metal halide lamp, or the like can be used.
The light irradiation intensity is not particularly limited, but the irradiation intensity peak at the absorption wavelength of the photopolymerization initiator contained in the adhesive is preferably 10 to 10,000 mW / cm ² . If the light irradiation intensity is less than 10 mW / cm ² , the reaction time becomes too long, and if it exceeds 10,000 mW / cm ² , the polarizing plate may be deteriorated by radiant heat from the lamp. The light irradiation time is also not particularly limited, but is preferably set so that the integrated light amount expressed as the product of the irradiation intensity and the irradiation time is 10 to 10,000 mJ / cm ² . If the integrated light quantity is less than 10 mJ / cm ² , the curing of the adhesive may not proceed sufficiently. On the other hand, if the integrated light quantity exceeds 10,000 mJ / cm ² , the polarizing plate may be deteriorated. is there.

  When curing by heat, it can be heated by a generally known method, and the conditions are not particularly limited. However, heating at a high temperature causes deterioration of the polarizing plate. Implemented.

  Even in the case of curing under the conditions of irradiation with active energy rays or heating, it is preferable to cure in the range where various functions of the polarizing plate such as the degree of polarization, the transmittance and the hue of the polarizing plate do not deteriorate.

An adhesive can also be used for bonding the polarizing plate and the retardation film. The pressure-sensitive adhesive is a kind of adhesive generally called a pressure-sensitive adhesive.
Specific examples include (meth) acrylate, oxetane, styrene butadiene rubber, butyl rubber, natural rubber, silicone rubber, polyisoprene, polybutene, polyvinyl ether, acrylic resin, and polyester. It is done.

  Among these adhesives or pressure-sensitive adhesives, (meth) acrylate-based, oxetane-based, acrylic resin-based, polyester-based, epoxy-based, and polyurethane resin-based adhesives or pressure-sensitive adhesives are preferable. These adhesives or pressure-sensitive adhesives are also preferable because of their high transparency and good weather resistance. Further, when using a thin polarizing plate, it is particularly preferable to use a (meth) acrylate, acrylic resin, or polyester adhesive.

  The example of the bonding process using a curable adhesive is demonstrated. As shown in FIG. 3, it rolls out from a roll-shaped linearly-polarizing plate (31), and a curable adhesive (34) is applied with a coating device (33). Examples of the coating apparatus at this time include a roll coater, a gravure coater, a knife coater, a rod coater, a slot orifice coater, an air doctor coater, a kiss coater, a blade coater, a die coater, and a comma coater.

A roll-like retardation film continuous laminated film (35) is unwound and both films are laminated by a laminating roll (36) so that foreign matter, air, etc. are not mixed. If necessary, a roll-like elliptically polarizing plate (38) can be obtained by curing and winding the adhesive by irradiation with heat or active energy rays (37). It is also possible to wind up while peeling the adhesive film for conveyance used for the retardation film continuous bonding film (35) after adhesive hardening.
Before the lamination, in order to improve the adhesion between the linear polarizing plate and the retardation film, the bonding surface of the roll-shaped linear polarizing plate (31) or the lamination of the retardation film continuous bonding film (35). At least one or both of the surfaces (retardation film surface) may be subjected to easy adhesion treatment with an easy adhesion treatment device (32) such as corona treatment or plasma treatment.

  The example of the bonding process using an adhesive is demonstrated. As shown in FIG. 4, it rolls out from a roll-like retardation film continuous bonding film (41), and applies an adhesive (44) with a coating apparatus (43). Examples of the coating apparatus at this time are the same as those described above.

If necessary, after irradiation with heat or active energy rays (45), the release film (46) is laminated with a laminating roll (47), and wound to form a roll-like adhesive processed retardation film continuously. A pasting film (48) can be obtained.
Before this lamination, in order to improve the adhesiveness between the pressure-sensitive adhesive and the retardation film, the bonding surface (retardation film surface) of the retardation film continuous bonding film (41) is subjected to corona treatment, plasma treatment, etc. You may perform an easy adhesion process with an easy adhesion processing apparatus (42).

FIG. 5 shows an example of a process for obtaining an adhesive processed retardation film continuous laminated film by transferring a film having a structure in which both sides of an adhesive are sandwiched between release films, generally called a supportless adhesive. Indicates. By unwinding the roll-like retardation film continuous bonding film (51) and laminating the supportless pressure-sensitive adhesive sheet (53) from which the release film has been peeled off by the release film take-up roll (54) with the laminating roll (55). An adhesive processed retardation film continuous laminated film (56) can be obtained.
Before this lamination, in order to improve the adhesiveness between the pressure-sensitive adhesive and the retardation film, on the bonding surface (retardation film surface) of the retardation film continuous bonding film (51), corona treatment, plasma treatment, etc. You may perform an easy adhesion process with an easy adhesion processing apparatus (52).

  In FIGS. 4 and 5, the roll-like retardation film continuous laminated film was adhesively processed and then the release film was laminated and wound. However, the release film was not laminated and continuously rolled as shown in FIG. 6. It is also possible to perform the steps after the laminating roll (65).

  Next, as shown in FIG. 6, it rolls out from a roll-shaped adhesion-processed retardation film continuous bonding film (61), peels the release film with a release film winding roll (62), and then rolls. The linear polarizing plate (64) is unwound and both films are laminated by a laminating roll (65) so that no foreign matter, air, etc. are mixed. If necessary, a roll-like elliptically polarizing plate (67) can be obtained by performing irradiation (66) with heat or active energy rays and winding. When winding up, it is also possible to wind up while peeling the adhesive film for conveyance used for the adhesive-processed retardation film continuous bonding film (61). Before this lamination, in order to improve the adhesiveness between the linear polarizing plate and the retardation film, an easy-adhesion processing device (63 such as corona treatment or plasma treatment) is applied to the bonding surface of the roll-shaped linear polarizing plate (64). ) May be performed.

  Rolled elliptically polarizing plates are manufactured by the above-described manufacturing method, but optical properties such as improving wavelength dispersion (making elliptical polarizing plates function equally and highly over the entire wavelength of visible light). In order to improve the quality, two or more retardation films may be bonded to the polarizing plate to form an elliptical polarizing plate. In that case, when the roll-like retardation film continuous pasting film after the second sheet is pasted, the target is a roll-shaped elliptical polarizing plate (rolled linear polarizing plate + retardation film). Is manufactured by the linear polarizing plate in the elliptically polarizing plate and the above-described manufacturing method through the already-laminated retardation film.

  The sheet-like body of the elliptically polarizing plate can be obtained by cutting the rolled elliptically polarizing plate obtained as described above into a predetermined shape. In addition, this cutting process can also be performed before winding up as a roll-like elliptically polarizing plate.

  The sheet of the elliptically polarizing plate obtained above can be used as an optical film for a liquid crystal display device. The elliptically polarizing plate can also be used as an optical film for preventing reflection of internal electrodes of a display device using organic electroluminescence.

Hereinafter, the present invention will be described more specifically with reference to examples and comparative examples.
The measurement method of physical properties and the evaluation method of effects in the present invention were performed according to the following methods.

(1) Ellipticity The ellipticity was measured using an automatic birefringence meter KOBRA-21ADH manufactured by Oji Scientific Instruments. The phase difference at 550 nm was approximated using Cauchy's equation.

(2) Effective usage rate c sheets of a sheet-like retardation film are cut out from a roll-shaped retardation film having an effective width of amm and an effective length of bmm, and all are bonded to a roll-shaped polarizing plate. At this time, when an area that can function effectively as an elliptically polarizing plate is obtained by laminating one sheet-like retardation film with a polarizing plate, the following equation (1) is elliptical: The effective usage rate R of the polarizing plate was defined.

Example 1
A roll-like retardation film (retardation value: 138 nm, slow axis: film longitudinal direction, effective width: 300 mm × effective length: 10,000 mm) manufactured by Sumitomo Chemical Co., Ltd. is used as the slow axis using the cutting step shown in FIG. On the other hand, the sheet was cut in a direction of 45 ° to obtain 22 rhombus-shaped retardation film sheets having a side of 300√2 mm.
Next, using the bonding process shown in FIG. 2, the roll-shaped retardation film “Slimliner SRL-0754AS” (hereinafter referred to as SRL) manufactured by Lintec Co., Ltd. All were bonded together to obtain a roll-like retardation film continuous bonded film (effective width 300 mm).
A microgravure so that a visible light curable adhesive “Aronix UV-3600” manufactured by Toagosei Co., Ltd. has a film thickness of 10 μm using the process shown in FIG. Coating was performed at a coating temperature of 25 ° C. using a coater. Next, it is bonded to a roll-shaped (linear) polarizing plate (effective width 300 mm × effective length 10000 mm) manufactured by Sumitomo Chemical Co., Ltd. with a laminate roll, and ultraviolet irradiation is performed using an ultraviolet irradiation device to which a metal halide lamp is attached. Gluing was performed. The integrated light amount was 1,200 mJ / cm ² (365 nm).
In this way, a roll-shaped elliptically polarizing plate having 22 rhombic retardation film sheets bonded together was obtained. None of the rolled elliptical polarizing plates had defects such as wrinkles, and all exhibited good appearance. At this time, the effective usage rate R of the elliptically polarizing plate was 93.3%. Moreover, when the obtained roll-shaped elliptical polarizing plate was cut and a part of the ellipticity was measured, the ellipticity at a light wavelength of 550 nm was 99.4%.

(Example 2)
A roll-like retardation film continuous laminated film (effective width 300 mm) was obtained in the same manner as in Example 1.
Using the process shown in FIG. 4 for this roll-like retardation film continuous laminated film, an acrylic adhesive “Arontack S-1511 (X)” (hereinafter referred to as S-1511) manufactured by Toagosei Co., Ltd. Was coated at a coating temperature of 25 ° C. with a comma coater so as to have a film thickness of 25 μm, and dried at 100 ° C. for 3 minutes.
Next, the same (linear) polarizing plate as in Example 1 was laminated with a laminating roll and laminated.
In this way, a roll-shaped elliptically polarizing plate having 22 rhombic retardation film sheets bonded together was obtained. None of the rolled elliptical polarizing plates had defects such as wrinkles, and all exhibited good appearance. At this time, the effective usage rate R of the elliptically polarizing plate was 93.3%. Moreover, when the obtained roll-shaped elliptical polarizing plate was cut and a part of the ellipticity was measured, the ellipticity at a light wavelength of 550 nm was 99.4%.

(Example 3)
A roll-like retardation film continuous laminated film (effective width 300 mm) was obtained in the same manner as in Example 1.
Using the process shown in FIG. 5, a supportless adhesive “SK-2057” (film thickness: 25 μm) manufactured by Soken Chemical Co., Ltd. was transferred at a temperature of 25 ° C. to this roll-like retardation film continuous laminated film. .
Next, the same (linear) polarizing plate as in Example 1 was laminated with a laminating roll and laminated.
In this way, a roll-shaped elliptically polarizing plate having 22 rhombic retardation film sheets bonded together was obtained. None of the rolled elliptical polarizing plates had defects such as wrinkles, and all exhibited good appearance. At this time, the effective usage rate R of the elliptically polarizing plate was 93.3%. Moreover, when the obtained roll-shaped elliptical polarizing plate was cut and a part of the ellipticity was measured, the ellipticity at a light wavelength of 550 nm was 99.4%.

(Comparative Example 1)
A roll-like retardation film similar to that in Example 1 was cut in a direction of 45 ° with respect to the slow axis by the method described in FIG. 1 of Patent Document 6, and a rectangular shape with one side of 150√2 mm ( (Square) 33 sheets of retardation film were obtained.
Next, 33 sheets of this rectangular retardation film sheet are all bonded to the roll-shaped transport film SRL using the fixing method shown in FIG. 2 of Patent Document 6, and a roll-shaped retardation film is continuously bonded. A film (effective width 150√2 mm) was obtained.
In this roll-like phase difference film continuous pasting film, using the process shown in Drawing 4 of patent documents 6, acrylic adhesive S-1511 is applied at 25 ° C with a comma coater so that film thickness may be 25 micrometers. It was coated and dried at 100 ° C. for 3 minutes.
Subsequently, it was bonded to a roll-shaped (linear) polarizing plate (effective width 150√2 mm × effective length 10,000 mm) manufactured by Sumitomo Chemical Co., Ltd. with a laminate roll, and 33 sheets of rectangular retardation film sheets were bonded. A roll-shaped elliptically polarizing plate was obtained. None of the rolled elliptical polarizing plates had defects such as wrinkles, and all exhibited good appearance. At this time, the effective usage rate R of the elliptically polarizing plate was 49.5%. Moreover, when the obtained roll-shaped elliptical polarizing plate was cut and a part of the ellipticity was measured, the ellipticity at a light wavelength of 550 nm was 99.4%.

  The present invention relates to a roll-like retardation film continuous laminated film and a production method thereof, and an elliptically polarizing plate using the same and a production method thereof, and relates to the fields of retardation film, elliptically polarizing plate and liquid crystal display device, and the use thereof It can be used in the field to do.

An example of a step of cutting a roll-like retardation film into a rectangular sheet. The example of the process of bonding a retardation film sheet to the adhesive film for conveyance of a roll form. The example of the lamination | stacking process of retardation film continuous bonding film and roll-shaped linearly-polarizing plate using a curable adhesive. The example of the adhesive coating process to a roll-like phase difference film continuous pasting film. The example of the supportless adhesive transfer process to a roll-like phase difference film continuous pasting film. The example of the lamination process of a roll-shaped adhesion-processed retardation film continuous bonding film and a roll-shaped linearly-polarizing plate.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 Roll-like phase difference film 12 Slow axis 13 Quadrilateral sheet 21 Roll-shaped conveyance adhesive roll 22 Retardation film sheet 23 Slow axis 24 Roll-like retardation film continuous bonding film 31 Roll shape Linear polarizing plate 32 Easy adhesion processing device 33 Coating device 34 Curing adhesive 35 Roll-like retardation film continuous laminating film 36 Laminating roll 37 Thermal oven or active energy ray irradiation device 38 Roll-like elliptical polarizing plate 41 Roll Retardation film continuous laminating film 42 Easy adhesion processing device 43 Coating device 44 Adhesive 45 Thermal oven or active energy ray irradiation device 46 Release film 47 Laminating roll 48 Roll-like adhesive processed retardation film continuous laminating Film 51 Roll-like retardation film continuous bonding film 52 Easy adhesion processing device 53 Roll-shaped supportless adhesive 54 Release film winding roll 55 Laminating roll 56 Roll-shaped adhesive processed retardation film continuous bonding film 61 Roll-shaped adhesive processed retardation film continuous bonding film 62 Release film winding Take-up roll 63 Easy adhesion treatment device 64 Roll-shaped linearly polarizing plate 65 Laminating roll 66 Thermal or active energy ray irradiation device 67 Roll-shaped elliptically polarizing plate

Claims (10)

From a roll-shaped retardation film having a slow axis or a fast axis (hereinafter simply referred to as a slow axis) substantially parallel to the longitudinal direction, at least one side of a square is a predetermined angle (0 ° with respect to the slow axis of the film). <Θ <180 °) The sheet is continuously cut and taken out, and the sheet is taken as a roll-like adhesive film for conveyance in the longitudinal direction of the film. A roll shape in which the slow axis has a predetermined angle (0 ° <θ <180 °) with respect to the longitudinal direction by continuous bonding so that the shaft has a predetermined angle (0 ° <θ <180 °). A roll-like retardation film continuous laminated film, wherein the retardation film is continuously laminated, and the rectangular sheet is a parallelogram or trapezoid. The roll-shaped linear polarizing plate whose absorption axis or transmission axis (hereinafter simply referred to as absorption axis) is substantially parallel to the longitudinal direction, and the roll-shaped retardation film continuous laminated film according to claim 1, A roll-shaped elliptically polarizing plate bonded and rolled so that the longitudinal direction is substantially parallel. The adhesive of a roll-shaped linearly polarizing plate and a roll-shaped retardation film continuous bonding film uses the curable adhesive which hardens | cures and adhere | attaches by the irradiation of a heat | fever or an active energy ray. Roll elliptical polarizing plate. The elliptically polarizing plate which consists of a sheet body obtained by cutting the roll-shaped elliptically polarizing plate of Claim 2 or 3 in a predetermined shape. A liquid crystal display device using the elliptically polarizing plate according to claim 2. A display device using organic electroluminescence, wherein the elliptically polarizing plate according to claim 2 is used. Cut from a roll-like retardation film whose slow axis is substantially parallel to the longitudinal direction so that at least one side of the square has a predetermined angle (0 ° <θ <180 °) with respect to the slow axis of the film. The single sheet is continuously taken out, and the single sheet is placed on a roll-shaped adhesive film for conveyance, with the slow axis of the single sheet being a predetermined angle (0 ° <θ <180 °) with respect to the longitudinal direction of the film. By continuously laminating so as to become, a slow axis has a predetermined angle (0 ° <θ <180 °) with respect to the longitudinal direction, and a roll-shaped retardation film is continuously laminated. A method for producing a film, wherein the rectangular sheet is a parallelogram or trapezoid, and a method for producing a roll-like retardation film continuous laminated film. The roll-shaped linearly polarizing plate whose absorption axis is substantially parallel to the longitudinal direction, and the roll-shaped retardation film continuous laminated film obtained by the production method according to claim 7, wherein the longitudinal directions of the roll-shaped retardation film are substantially parallel to each other. A method for producing a roll-shaped elliptically polarizing plate, characterized in that it is bonded to form a roll. 9. A curable adhesive that is cured and bonded by irradiation of heat or active energy rays is used when bonding a roll-shaped linearly polarizing plate and a roll-shaped retardation film continuous laminated film. The manufacturing method of the elliptical polarizing plate of roll shape as described in 2. A method for producing an elliptically polarizing plate, wherein the roll-like elliptically polarizing plate according to claim 8 or 9 is cut into a predetermined shape.

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