WO2016009663A1 - Procédé de production d'un stratifié - Google Patents

Procédé de production d'un stratifié Download PDF

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Publication number
WO2016009663A1
WO2016009663A1 PCT/JP2015/053071 JP2015053071W WO2016009663A1 WO 2016009663 A1 WO2016009663 A1 WO 2016009663A1 JP 2015053071 W JP2015053071 W JP 2015053071W WO 2016009663 A1 WO2016009663 A1 WO 2016009663A1
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WIPO (PCT)
Prior art keywords
base material
resin base
resin
manufacturing
heating
Prior art date
Application number
PCT/JP2015/053071
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English (en)
Japanese (ja)
Inventor
竜弥 荒木
章仁 阿部
近藤　誠司
敏広 菅野
山下　裕司
裕紀 松山
浩明 川西
Original Assignee
日東電工株式会社
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Application filed by 日東電工株式会社 filed Critical 日東電工株式会社
Priority to KR1020177004312A priority Critical patent/KR102450433B1/ko
Priority to KR1020227020960A priority patent/KR20220092637A/ko
Priority to KR1020217007420A priority patent/KR102450442B1/ko
Priority to KR1020227020962A priority patent/KR102580445B1/ko
Priority to CN201580038875.3A priority patent/CN106537196B/zh
Publication of WO2016009663A1 publication Critical patent/WO2016009663A1/fr

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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B37/00—Methods or apparatus for laminating, e.g. by curing or by ultrasonic bonding
    • B32B37/06—Methods or apparatus for laminating, e.g. by curing or by ultrasonic bonding characterised by the heating method
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B27/00—Layered products comprising a layer of synthetic resin
    • B32B27/30—Layered products comprising a layer of synthetic resin comprising vinyl (co)polymers; comprising acrylic (co)polymers
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B27/00—Layered products comprising a layer of synthetic resin
    • B32B27/06—Layered products comprising a layer of synthetic resin as the main or only constituent of a layer, which is next to another layer of the same or of a different material
    • B32B27/08—Layered products comprising a layer of synthetic resin as the main or only constituent of a layer, which is next to another layer of the same or of a different material of synthetic resin
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B27/00—Layered products comprising a layer of synthetic resin
    • B32B27/30—Layered products comprising a layer of synthetic resin comprising vinyl (co)polymers; comprising acrylic (co)polymers
    • B32B27/306—Layered products comprising a layer of synthetic resin comprising vinyl (co)polymers; comprising acrylic (co)polymers comprising vinyl acetate or vinyl alcohol (co)polymers
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B27/00—Layered products comprising a layer of synthetic resin
    • B32B27/32—Layered products comprising a layer of synthetic resin comprising polyolefins
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B37/00—Methods or apparatus for laminating, e.g. by curing or by ultrasonic bonding
    • B32B37/14—Methods or apparatus for laminating, e.g. by curing or by ultrasonic bonding characterised by the properties of the layers
    • B32B37/24—Methods or apparatus for laminating, e.g. by curing or by ultrasonic bonding characterised by the properties of the layers with at least one layer not being coherent before laminating, e.g. made up from granular material sprinkled onto a substrate
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B7/00—Layered products characterised by the relation between layers; Layered products characterised by the relative orientation of features between layers, or by the relative values of a measurable parameter between layers, i.e. products comprising layers having different physical, chemical or physicochemical properties; Layered products characterised by the interconnection of layers
    • B32B7/03—Layered products characterised by the relation between layers; Layered products characterised by the relative orientation of features between layers, or by the relative values of a measurable parameter between layers, i.e. products comprising layers having different physical, chemical or physicochemical properties; Layered products characterised by the interconnection of layers with respect to the orientation of features
    • B32B7/035—Layered products characterised by the relation between layers; Layered products characterised by the relative orientation of features between layers, or by the relative values of a measurable parameter between layers, i.e. products comprising layers having different physical, chemical or physicochemical properties; Layered products characterised by the interconnection of layers with respect to the orientation of features using arrangements of stretched films, e.g. of mono-axially stretched films arranged alternately
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B5/00—Optical elements other than lenses
    • G02B5/30—Polarising elements
    • G—PHYSICS
    • G02—OPTICS
    • G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
    • G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
    • G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour 
    • G02F1/13—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour  based on liquid crystals, e.g. single liquid crystal display cells
    • G02F1/133—Constructional arrangements; Operation of liquid crystal cells; Circuit arrangements
    • G02F1/1333—Constructional arrangements; Manufacturing methods
    • G02F1/1335—Structural association of cells with optical devices, e.g. polarisers or reflectors
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B37/00—Methods or apparatus for laminating, e.g. by curing or by ultrasonic bonding
    • B32B37/14—Methods or apparatus for laminating, e.g. by curing or by ultrasonic bonding characterised by the properties of the layers
    • B32B37/24—Methods or apparatus for laminating, e.g. by curing or by ultrasonic bonding characterised by the properties of the layers with at least one layer not being coherent before laminating, e.g. made up from granular material sprinkled onto a substrate
    • B32B2037/243—Coating
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B38/00—Ancillary operations in connection with laminating processes
    • B32B38/0012—Mechanical treatment, e.g. roughening, deforming, stretching
    • B32B2038/0028—Stretching, elongating
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B2307/00—Properties of the layers or laminate
    • B32B2307/40—Properties of the layers or laminate having particular optical properties
    • B32B2307/42—Polarizing, birefringent, filtering
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B2309/00—Parameters for the laminating or treatment process; Apparatus details
    • B32B2309/02—Temperature

Definitions

  • the present invention relates to a method for manufacturing a laminate. Specifically, it is related with the manufacturing method of the laminated body which has a resin base material and the polyvinyl alcohol (PVA) type-resin layer formed on this resin base material.
  • PVA polyvinyl alcohol
  • a method has been proposed in which a polarizing film is obtained by coating and forming a PVA-based resin layer on a resin substrate, and stretching and dyeing the laminate (for example, Patent Document 1 and Patent Document 2).
  • a polarizing film with a small thickness can be obtained, and thus, for example, it has been attracting attention as being able to contribute to a reduction in the thickness of an image display device.
  • unevenness is likely to occur in the performance (specifically, film thickness, optical characteristics, appearance) of the obtained polarizing film.
  • the present invention has been made to solve the above-described conventional problems, and a main object thereof is to provide a laminate capable of producing a polarizing film having uniform performance.
  • the method for producing a laminate of the present invention includes a step of heating a resin base material to a glass transition temperature (Tg) of the resin base material of ⁇ 15 ° C. or higher, and a step of forming a polyvinyl alcohol resin layer on the resin base material And in this order.
  • Tg glass transition temperature
  • the said resin base material is unwound from the resin base material roll by which the elongate resin base material was wound by roll shape, and the said heating process is performed.
  • the above heating step is performed after storing in the wound state.
  • the unwinding step, the heating step, and the polyvinyl alcohol-based resin layer forming step are continuously performed.
  • the heating step is performed at a glass transition temperature (Tg) of the resin base material of + 15 ° C. or lower. In one embodiment, the heating step is performed while transporting the resin base material with a transport roll installed in a heating furnace. In one embodiment, the holding angle of the conveyance roll in the said heating furnace is 90 degrees or more. In one embodiment, the distance between the centers of the conveyance rolls in the heating furnace is 2 m or less. In one embodiment, the heating step is performed while conveying the resin base material with a tenter. In one embodiment, the shrinkage rate of the resin base material by the said heating is 3% or less. In one embodiment, the resin base material is formed of a polyethylene terephthalate resin. In one embodiment, the resin substrate is stretched in advance.
  • Tg glass transition temperature
  • the said polyvinyl alcohol-type resin layer is formed by apply
  • the manufacturing method of a polarizing film is provided. The manufacturing method of this polarizing film uses the laminated body obtained by the said manufacturing method. In one embodiment, the process of extending the above-mentioned layered product is included.
  • the manufacturing method of a polarizing plate is provided. The manufacturing method of this polarizing plate includes the process of laminating
  • a stretched laminate is provided.
  • This stretched laminate has a resin substrate and a polyvinyl alcohol-based resin layer formed on the resin substrate.
  • the film thickness unevenness within the size of 200 mm (MD) ⁇ 200 mm (TD) of the polyvinyl alcohol resin layer is 0.25 ⁇ m or less, and the size of 200 mm (MD) ⁇ 200 mm (TD) of the polyvinyl alcohol resin layer.
  • the slow axis unevenness is 0.50 ° or less.
  • the manufacturing apparatus of a laminated body includes unwinding means for unwinding the resin base material from a resin base material roll in which the long resin base material is wound into a roll, and the long resin material.
  • a transporting roll for transporting the base material a heating furnace for heating the resin base material to a glass transition temperature (Tg) of the resin base material of ⁇ 15 ° C. or higher, and a polyvinyl alcohol resin on the heated resin base material.
  • the manufacturing apparatus includes unwinding means for unwinding the resin base material from a resin base material roll in which the long resin base material is wound into a roll, and the long resin material.
  • a tenter that grips and conveys both ends of the base material and heats the resin base material gripped at both ends with the clip of the tenter to a glass transition temperature (Tg) of ⁇ 15 ° C. or higher.
  • the resin substrate is subjected to heat treatment at a predetermined temperature or more to reduce (homogenize) the surface unevenness of the resin substrate (for example, a gauge band generated when the resin substrate is wound). )can do.
  • a PVA-based resin layer having excellent thickness uniformity can be formed on the resin substrate.
  • a polarizing film for example, sufficiently satisfying the quality required for a liquid crystal television
  • FIG. 1 is a schematic cross-sectional view of a laminate according to one embodiment of the present invention.
  • the laminate 10 is obtained by forming a polyvinyl alcohol (PVA) resin layer 12 on the resin substrate 11.
  • PVA polyvinyl alcohol
  • the resin base material is typically long.
  • the thickness of the resin substrate is preferably 20 ⁇ m to 300 ⁇ m, more preferably 50 ⁇ m to 200 ⁇ m.
  • the resin base material examples include ester resins such as polyethylene terephthalate resins, cycloolefin resins, olefin resins such as polypropylene, (meth) acrylic resins, polyamide resins, polycarbonate resins, and the like.
  • Examples include copolymer resins.
  • a polyethylene terephthalate resin is used.
  • amorphous polyethylene terephthalate resin is preferably used.
  • Specific examples of the amorphous polyethylene terephthalate resin include a copolymer further containing isophthalic acid as a dicarboxylic acid, and a copolymer further containing cyclohexanedimethanol as a glycol.
  • the glass transition temperature (Tg) of the resin base material is preferably 170 ° C. or lower.
  • the laminate can be stretched at a temperature at which the crystallization of the PVA resin does not proceed rapidly, and defects due to the crystallization (for example, the orientation of the PVA resin layer due to the stretching) Hindering) can be suppressed.
  • the glass transition temperature of the resin substrate is preferably 60 ° C. or higher.
  • the glass transition temperature (Tg) is a value determined according to JIS K 7121.
  • the resin base material is molded by any appropriate method.
  • the molding method include a melt extrusion method, a solution casting method (solution casting method), a calendar method, and a compression molding method.
  • the melt extrusion method is preferable.
  • the surface of the resin substrate may be subjected to surface modification treatment (for example, corona treatment) or an easy adhesion layer may be formed. According to such a process, the adhesiveness of a resin base material and a PVA-type resin layer can be improved.
  • the surface modification treatment and / or the formation of the easy-adhesion layer may be performed before the heat treatment described below or after the heat treatment. Moreover, when performing the extending
  • the resin substrate is stretched before the heat treatment described below.
  • Arbitrary appropriate methods can be employ
  • the stretching of the resin base material may be performed in one stage or in multiple stages. When performed in multiple stages, the stretch ratio of the resin base material described later is the product of the stretch ratios of the respective stages.
  • the stretching method is not particularly limited, and may be an air stretching method or an underwater stretching method.
  • the stretching direction of the resin base material can be set as appropriate.
  • a long resin base is stretched in the width direction.
  • the resin base material is transported in the longitudinal direction and stretched in a direction (TD) orthogonal to the transport direction (MD).
  • TD direction
  • orthogonal includes a case of being substantially orthogonal.
  • substantially orthogonal includes the case of 90 ° ⁇ 5.0 °, preferably 90 ° ⁇ 3.0 °, more preferably 90 ° ⁇ 1.0 °.
  • the stretching temperature of the resin base material can be set to any appropriate value depending on the forming material of the resin base material, the stretching method, and the like.
  • the stretching temperature is typically Tg ⁇ 10 ° C. to Tg + 80 ° C. with respect to the glass transition temperature (Tg) of the resin substrate.
  • Tg glass transition temperature
  • the stretching temperature is preferably 70 ° C. to 150 ° C., more preferably 90 ° C. to 130 ° C.
  • the draw ratio of the resin base material is preferably 1.5 times or more with respect to the original length of the resin base material. By setting it as such a range, the below-mentioned partial film thickness nonuniformity can be suppressed favorably. On the other hand, the draw ratio of the resin base material is preferably 3.0 times or less with respect to the original length of the resin base material. By setting it as such a range, generation
  • the long resin base is wound into a roll.
  • the resin base material When the resin base material is molded, partial film thickness unevenness occurs. By winding in this state, the resin base material may be uneven.
  • the winding tension is typically 60 N / m to 150 N / m (unit: N / m is the tension per unit width length).
  • the wound resin base material (resin base material roll) can be stored (leaved) in a wound state for any appropriate period until it is used for the next step. For example, after the molding of the resin base material, when the PVA resin layer is not continuously formed (cannot be performed), the resin base material is stored in a wound state.
  • the resin base roll can be stored in any appropriate atmosphere.
  • the storage temperature is, for example, 15 ° C. to 35 ° C.
  • the relative humidity is, for example, 40% RH to 80% RH.
  • the resin base material is heated. Specifically, the resin substrate is heated with hot air, an infrared heater, a roll heater, or the like.
  • the heating temperature is a glass transition temperature (Tg) of the resin base material of ⁇ 15 ° C. or higher, preferably Tg ⁇ 10 ° C. or higher, more preferably Tg ⁇ 5 ° C. or higher.
  • Tg glass transition temperature
  • the heating temperature is preferably 68 ° C. or higher.
  • the heating temperature is preferably (Tg) + 15 ° C. or less, more preferably Tg + 10 ° C. or less.
  • the heating temperature is preferably 80 ° C. or lower.
  • the heating time is preferably 70 seconds to 150 seconds, more preferably 75 seconds to 100 seconds.
  • the resin base material can shrink by heating.
  • the resin substrate when the resin substrate is stretched in the width direction before heating, the resin substrate can be contracted in the width direction (TD contraction) by heating.
  • the shrinkage rate (TD shrinkage rate) of the resin base material is preferably 3% or less, more preferably 2% or less, and particularly preferably 1.5% or less. If it is such a range, generation
  • the TD shrinkage rate is calculated by the following formula.
  • TD shrinkage (%) ⁇ 1- (resin substrate width after heating (W 1 ) / resin substrate width before heating (W 0 )) ⁇ ⁇ 100
  • the resin base material is heated while being conveyed.
  • the heating method include a method of transporting a resin base material with a transport roll installed in a heating furnace, and a method of heating while transporting a resin base material with a tenter. According to the former, the enlargement of equipment can be suppressed. According to the latter, generation
  • FIGS. 2 (a) and 2 (b) Specific examples in the case of using a transport roll are shown in FIGS. 2 (a) and 2 (b).
  • the resin base material 11 is heated by conveying the resin base material 11 in the longitudinal direction by the free rolls R2 to R5 installed in the oven furnace A. From the viewpoint of production speed, it is preferable to install four or more free rolls in the oven furnace as in the illustrated example.
  • the angle of hold of the free roll in the oven furnace is preferably 90 ° or more.
  • the holding angle ⁇ of the free rolls R2 and R5 is 90 °
  • the holding angle ⁇ of the free rolls R3 and R4 is 180 °.
  • the holding angle ⁇ of the free rolls R2 to R5 is 90 °.
  • the holding angle is a straight line connecting the center point of the free roll and the contact start point of the resin substrate and the free roll when the free roll is viewed from a cross section perpendicular to the axial direction, and the center of the free roll. It is an angle formed by a straight line connecting the point and the contact end point of the resin base material and the free roll.
  • the interval between the free rolls in the oven furnace (the distance between the centers of the rolls) is preferably 2 m or less. Further, the distance between the two free rolls installed so as to straddle the entrance / exit of the oven furnace (between R1 and R2 and between R5 and R6 in the illustrated example) is also preferably 2 m or less.
  • the shrinkage of the resin base material may be related to the stretching ratio of the resin base material, the heating temperature, and the like.
  • FIG. 1 A specific example of using a tenter is shown in FIG.
  • the left and right clips 21, 21 of the tenter respectively hold both ends of the resin base material 11 (on a line orthogonal to the transport direction) and transport the heating zone at a predetermined speed in the longitudinal direction.
  • the resin substrate 11 is heated.
  • the distance between clips in the transport direction (distance between adjacent clip ends) is preferably 20 mm or less, and more preferably 10 mm or less.
  • the clip width is preferably 20 mm or more, more preferably 30 mm or more.
  • the TD shrinkage of the resin base material can be controlled by adjusting the distance between the left and right clips, for example.
  • the TD shrinkage rate is substantially 0%.
  • the resin substrate can be TD-stretched by increasing the distance between the left and right clips.
  • the TD change rate of the resin base material is preferably 1.00 times or more, more preferably 1.00 times to 1.10 times.
  • PVA-type resin layer Arbitrary appropriate resin may be employ
  • examples thereof include polyvinyl alcohol and ethylene-vinyl alcohol copolymer.
  • Polyvinyl alcohol is obtained by saponifying polyvinyl acetate.
  • the ethylene-vinyl alcohol copolymer can be obtained by saponifying an ethylene-vinyl acetate copolymer.
  • the degree of saponification of the PVA-based resin is usually 85 mol% to 100 mol%, preferably 95.0 mol% to 99.95 mol%, more preferably 99.0 mol% to 99.93 mol%. .
  • the degree of saponification can be determined according to JIS K 6726-1994. By using a PVA-based resin having such a saponification degree, a polarizing film having excellent durability can be obtained. If the degree of saponification is too high, there is a risk of gelation.
  • the average degree of polymerization of the PVA resin can be appropriately selected according to the purpose.
  • the average degree of polymerization is usually 1000 to 10,000, preferably 1200 to 4500, and more preferably 1500 to 4300.
  • the average degree of polymerization can be determined according to JIS K 6726-1994.
  • the PVA-based resin layer is preferably formed by applying a coating solution containing a PVA-based resin on a resin base material and drying it.
  • the coating solution is typically a solution obtained by dissolving the PVA resin in a solvent.
  • the solvent include water, dimethyl sulfoxide, dimethylformamide, dimethylacetamide, N-methylpyrrolidone, various glycols, polyhydric alcohols such as trimethylolpropane, and amines such as ethylenediamine and diethylenetriamine. These may be used alone or in combination of two or more. Among these, water is preferable.
  • the concentration of the PVA resin in the solution is preferably 3 to 20 parts by weight with respect to 100 parts by weight of the solvent. With such a resin concentration, a uniform coating film in close contact with the resin substrate can be formed.
  • the additive may be contained in the coating liquid.
  • the additive include a plasticizer and a surfactant.
  • the plasticizer include polyhydric alcohols such as ethylene glycol and glycerin.
  • the surfactant include nonionic surfactants. These can be used for the purpose of further improving the uniformity, dyeability and stretchability of the resulting PVA-based resin layer.
  • an easily bonding component is mentioned, for example. By using the easy-adhesion component, the adhesion between the resin base material and the PVA-based resin layer can be improved. As a result, for example, problems such as peeling of the PVA resin layer from the resin base material can be suppressed, and dyeing and underwater stretching described later can be performed satisfactorily.
  • modified PVA such as acetoacetyl-modified PVA is used.
  • any appropriate method can be adopted as a coating method of the coating solution. Examples thereof include a roll coating method, a spin coating method, a wire bar coating method, a dip coating method, a die coating method, a curtain coating method, a spray coating method, a knife coating method (comma coating method, etc.).
  • a die coating method is employed.
  • the coating liquid is applied with the gap between the resin base material and the die (for example, fountain die, slot die) constant, a coating film having extremely excellent thickness uniformity can be obtained.
  • the resin substrate is uneven, the distance between the resin substrate and the die lip is not uniform, and it may be difficult to form a uniform coating film. Therefore, when the die coating method is employed, the effect of the heat treatment can be significantly obtained.
  • the coating solution is applied so that the thickness of the PVA resin layer after drying is preferably 3 ⁇ m to 40 ⁇ m, more preferably 3 ⁇ m to 20 ⁇ m.
  • the coating / drying temperature of the coating solution is preferably 50 ° C. or higher.
  • a PVA resin layer is formed continuously after the heating.
  • the PVA resin layer is formed on the resin substrate without winding the resin substrate after heating. It is because the effect by the said heating can be acquired favorably.
  • the material constituting the primer layer is not particularly limited as long as the material exhibits a certain degree of strong adhesion to both the resin base material and the PVA resin layer.
  • a thermoplastic resin excellent in transparency, heat stability, stretchability, etc. is used.
  • the thermoplastic resin include an acrylic resin, a polyolefin resin, a polyester resin, a polyvinyl alcohol resin, or a mixture thereof.
  • the effect by the said heat processing can be acquired favorably.
  • FIG. 4 there is a mode in which unwinding, heating, and PVA-based resin layer forming steps are sequentially performed by a series of lines that convey a long resin base material.
  • the laminated body manufacturing apparatus 100 includes a plurality of transport rolls 90.
  • the stretched laminate of the present invention is produced by stretching the laminate.
  • the stretched laminate is produced by stretching the laminate at a stretch ratio of 1.5 times or more and 3.0 times or less by an air stretching method. Details of the method of stretching the laminate are as described below.
  • the film thickness unevenness within the size of 200 mm (MD) ⁇ 200 mm (TD) of the PVA resin layer is preferably 0.25 ⁇ m or less, more preferably 0.20 ⁇ m or less.
  • the slow axis unevenness within the size of 200 mm (MD) ⁇ 200 mm (TD) of the PVA resin layer in the stretched laminate is preferably 0.50 ° or less, more preferably 0.30 ° or less, and particularly preferably 0.8. It is 25 degrees or less.
  • the polarizing film of the present invention is produced by performing a treatment for using the PVA resin layer of the laminate as a polarizing film.
  • Examples of the treatment for forming the polarizing film include dyeing treatment, stretching treatment, insolubilization treatment, crosslinking treatment, washing treatment, and drying treatment. These processes can be appropriately selected depending on the purpose. Further, the processing order, the processing timing, the number of processings, and the like can be set as appropriate. Each process will be described below.
  • the dyeing process is typically performed by dyeing the PVA resin layer with a dichroic substance. Preferably, it is performed by adsorbing a dichroic substance to the PVA resin layer.
  • the adsorption method include a method of immersing a PVA resin layer (laminated body) in a staining solution containing a dichroic substance, a method of applying the staining solution to a PVA resin layer, and a method of applying the staining solution to a PVA system.
  • Examples include a method of spraying on the resin layer. Preferably, it is a method of immersing the laminate in the staining solution. It is because a dichroic substance can adsorb
  • the dichroic substance examples include iodine and organic dyes. These may be used alone or in combination of two or more.
  • the dichroic material is preferably iodine.
  • the staining solution is preferably an iodine aqueous solution.
  • the blending amount of iodine is preferably 0.05 to 5.0 parts by weight with respect to 100 parts by weight of water. In order to increase the solubility of iodine in water, it is preferable to add an iodide to the aqueous iodine solution.
  • Examples of the iodide include potassium iodide, lithium iodide, sodium iodide, zinc iodide, aluminum iodide, lead iodide, copper iodide, barium iodide, calcium iodide, tin iodide, and titanium iodide. Etc. Among these, potassium iodide is preferable.
  • the blending amount of iodide is preferably 0.3 to 15 parts by weight with respect to 100 parts by weight of water.
  • the liquid temperature during staining of the staining liquid is preferably 20 ° C. to 40 ° C.
  • the immersion time is preferably 10 seconds to 300 seconds. Under such conditions, the dichroic substance can be sufficiently adsorbed to the PVA resin layer.
  • the staining conditions concentration, liquid temperature, immersion time
  • immersion time is set so that the polarization degree of the polarizing film obtained may be 99.98% or more.
  • the immersion time is set so that the single transmittance of the obtained polarizing film is about 40%.
  • Extension process Any appropriate method can be adopted as a method for stretching the laminate. Specifically, it may be fixed end stretching (for example, a method using a tenter stretching machine) or free end stretching (for example, a method of uniaxial stretching through a laminate between rolls having different peripheral speeds). Moreover, simultaneous biaxial stretching (for example, a method using a simultaneous biaxial stretching machine) or sequential biaxial stretching may be used.
  • the stretching of the laminate may be performed in one stage or in multiple stages. When performed in multiple stages, the draw ratio (maximum draw ratio) of the laminate described later is the product of the draw ratios of the respective stages.
  • the stretching treatment may be an underwater stretching method performed by immersing the laminate in a stretching bath, or an air stretching method.
  • the underwater stretching treatment is performed at least once, and more preferably, the underwater stretching treatment and the air stretching treatment are combined.
  • the PVA resin layer can be stretched at a temperature lower than the glass transition temperature (typically about 80 ° C.) of the resin base material and the PVA resin layer while suppressing the crystallization. It can be stretched at a high magnification. As a result, a polarizing film having excellent optical characteristics (for example, the degree of polarization) can be manufactured.
  • any appropriate direction can be selected as the stretching direction of the laminate. In one embodiment, it extends
  • the stretching temperature of the laminate can be set to any appropriate value depending on the resin base material, the stretching method, and the like.
  • the stretching temperature is preferably equal to or higher than the glass transition temperature (Tg) of the resin substrate, more preferably the glass transition temperature (Tg) of the resin substrate + 10 ° C., and particularly preferably Tg + 15 ° C. That's it.
  • the stretching temperature of the laminate is preferably 170 ° C. or lower.
  • the liquid temperature of the stretching bath is preferably 40 ° C. to 85 ° C., more preferably 50 ° C. to 85 ° C. If it is such temperature, it can extend
  • the glass transition temperature (Tg) of the resin base material is preferably 60 ° C. or higher in relation to the formation of the PVA-based resin layer. In this case, when the stretching temperature is lower than 40 ° C., there is a possibility that the stretching cannot be satisfactorily performed even in consideration of plasticization of the resin base material with water.
  • the higher the temperature of the stretching bath the higher the solubility of the PVA-based resin layer, and there is a possibility that excellent optical properties cannot be obtained.
  • the laminate When employing an underwater stretching method, it is preferable to stretch the laminate by immersing it in an aqueous boric acid solution (stretching in boric acid in water).
  • an aqueous boric acid solution as the stretching bath, the PVA resin layer can be provided with rigidity that can withstand the tension applied during stretching and water resistance that does not dissolve in water.
  • boric acid can form a tetrahydroxyborate anion in an aqueous solution and crosslink with a PVA resin by hydrogen bonding.
  • rigidity and water resistance can be imparted to the PVA-based resin layer, the film can be stretched satisfactorily, and a polarizing film having excellent optical properties can be produced.
  • the boric acid aqueous solution is preferably obtained by dissolving boric acid and / or borate in water as a solvent.
  • the boric acid concentration is preferably 1 to 10 parts by weight with respect to 100 parts by weight of water. By setting the boric acid concentration to 1 part by weight or more, dissolution of the PVA resin layer can be effectively suppressed, and a polarizing film having higher characteristics can be produced.
  • an aqueous solution obtained by dissolving a boron compound such as borax, glyoxal, glutaraldehyde, or the like in a solvent can also be used.
  • iodide is blended in the stretching bath (boric acid aqueous solution).
  • the stretching bath boric acid aqueous solution
  • concentration of iodide is preferably 0.05 to 15 parts by weight, more preferably 0.5 to 8 parts by weight with respect to 100 parts by weight of water.
  • the immersion time of the laminate in the stretching bath is preferably 15 seconds to 5 minutes.
  • the draw ratio (maximum draw ratio) of the laminate is typically 4.0 times or more, preferably 5.0 times or more, with respect to the original length of the laminate. Such a high draw ratio can be achieved, for example, by employing an underwater drawing method (boric acid underwater drawing).
  • the “maximum stretch ratio” refers to a stretch ratio immediately before the laminate is ruptured. Separately, a stretch ratio at which the laminate is ruptured is confirmed, and a value that is 0.2 lower than that value. .
  • the underwater stretching process is performed after the dyeing process.
  • the insolubilization treatment is typically performed by immersing the PVA resin layer in a boric acid aqueous solution.
  • a boric acid aqueous solution When an underwater stretching method is employed, water resistance can be imparted to the PVA-based resin layer by performing insolubilization treatment.
  • the concentration of the boric acid aqueous solution is preferably 1 to 4 parts by weight with respect to 100 parts by weight of water.
  • the liquid temperature of the insolubilizing bath (boric acid aqueous solution) is preferably 20 ° C. to 50 ° C.
  • the insolubilization process is performed after the laminate is manufactured and before the dyeing process or the underwater stretching process.
  • the crosslinking treatment is typically performed by immersing the PVA resin layer in a boric acid aqueous solution. By performing the crosslinking treatment, water resistance can be imparted to the PVA resin layer.
  • the concentration of the boric acid aqueous solution is preferably 1 to 4 parts by weight with respect to 100 parts by weight of water.
  • blend an iodide by performing a crosslinking process after the said dyeing
  • the blending amount of iodide is preferably 1 to 5 parts by weight with respect to 100 parts by weight of water.
  • the liquid temperature of the crosslinking bath is preferably 20 ° C. to 50 ° C.
  • the crosslinking treatment is performed before the underwater stretching treatment.
  • the dyeing process, the crosslinking process and the underwater stretching process are performed in this order.
  • the cleaning treatment is typically performed by immersing the PVA resin layer in an aqueous potassium iodide solution.
  • the drying temperature in the drying treatment is preferably 30 ° C. to 100 ° C.
  • the obtained polarizing film is substantially a PVA resin film in which a dichroic substance is adsorbed and oriented.
  • the thickness of the polarizing film is preferably 15 ⁇ m or less, more preferably 10 ⁇ m or less, further preferably 7 ⁇ m or less, and particularly preferably 5 ⁇ m or less.
  • Such a polarizing film can suppress the occurrence of cracks and the like in an environmental test (for example, an 80 ° C. environmental test).
  • the thickness of the polarizing film is preferably 0.5 ⁇ m or more, more preferably 1.0 ⁇ m or more.
  • Such a polarizing film can be extremely excellent in transportability during production.
  • the polarizing film preferably exhibits absorption dichroism at any wavelength between 380 nm and 780 nm.
  • the polarizing film preferably has a degree of polarization of 99.9% or more at a single transmittance of 42% or more.
  • the polarizing plate of the present invention has the polarizing film.
  • the polarizing plate includes the polarizing film and a protective film disposed on at least one side of the polarizing film.
  • the resin base material may be used as it is, or a film different from the resin base material may be used.
  • the material for forming the protective film include (meth) acrylic resins, cellulose resins such as diacetyl cellulose and triacetyl cellulose, cycloolefin resins, olefin resins such as polypropylene, and ester resins such as polyethylene terephthalate resins. , Polyamide resins, polycarbonate resins, and copolymer resins thereof.
  • the thickness of the protective film is preferably 10 ⁇ m to 100 ⁇ m.
  • the resin base material is used as it is as a protective film without being peeled off from the polarizing film.
  • the resin base material is peeled from the polarizing film, and another film is laminated.
  • the protective film may be laminated on the polarizing film via an adhesive layer, or may be laminated in close contact (without an adhesive layer).
  • the adhesive layer is typically formed of an adhesive or a pressure-sensitive adhesive. According to the present invention, since a polarizing film having extremely excellent thickness uniformity can be obtained, the protective film can be favorably laminated on the polarizing film.
  • Example 1-1 (Production of laminate) It is composed of amorphous isophthalic acid copolymerized polyethylene terephthalate (IPA copolymerized PET) having a water absorption rate of 0.75% and a glass transition temperature (Tg) of 75 ° C., and TD-stretched 2.0 times at 115 ° C. in advance.
  • An elongated resin substrate having a thickness of 100 ⁇ m was wound into a roll with a tension of 100 N / m to form a resin substrate roll, and stored in an environment of 25 ° C. and a relative humidity of 60% RH for 30 days. Thereafter, the resin base material was unwound from the resin base material roll and subjected to heat treatment at 70 ° C.
  • IPA copolymerized PET amorphous isophthalic acid copolymerized polyethylene terephthalate
  • Tg glass transition temperature
  • the obtained laminate was uniaxially stretched at a free end 2.0 times in the longitudinal direction between rolls having different peripheral speeds in an oven at 115 ° C. (in-air stretching).
  • the laminate was immersed in an insolubilization bath (a boric acid aqueous solution obtained by blending 3 parts by weight of boric acid with respect to 100 parts by weight of water) for 30 seconds (insolubilization treatment).
  • the single transmittance (Ts) of the obtained polarizing film is 40% in a dyeing bath (iodine aqueous solution obtained by mixing iodine and potassium iodide in water at a weight ratio of 1: 7) at a liquid temperature of 30 ° C.
  • Example 1-2 A polarizing film was formed on the resin substrate in the same manner as in Example 1-1 except that the temperature of the heat treatment was set to 75 ° C. when the laminate was produced.
  • Example 1-3 A polarizing film was formed on the resin substrate in the same manner as in Example 1-1 except that the temperature of the heat treatment was set to 80 ° C. when the laminate was produced.
  • Example 1-4 A polarizing film was formed on the resin substrate in the same manner as in Example 1-1 except that the temperature of the heat treatment was set to 90 ° C. when the laminate was produced.
  • Example 1-5 A polarizing film was formed on the resin substrate in the same manner as in Example 1-1 except that the temperature of the heat treatment was set to 100 ° C. when the laminate was produced.
  • Example 2-1 (Production of laminate) A laminate was produced in the same manner as in Example 1-1.
  • the obtained laminate was stretched 4.0 times in the width direction by free end uniaxial stretching using a tenter stretching machine under heating at 115 ° C. (stretching treatment).
  • the laminate was immersed in an insolubilization bath (a boric acid aqueous solution obtained by blending 3 parts by weight of boric acid with respect to 100 parts by weight of water) for 30 seconds (insolubilization treatment).
  • the single transmittance (Ts) of the obtained polarizing film is 40% in a dyeing bath (iodine aqueous solution obtained by mixing iodine and potassium iodide in water at a weight ratio of 1: 7) at a liquid temperature of 30 ° C.
  • Example 2-2 A polarizing film was formed on the resin substrate in the same manner as in Example 2-1, except that the temperature of the heat treatment was set to 75 ° C. when the laminate was produced.
  • Example 2-3 A polarizing film was formed on the resin substrate in the same manner as in Example 2-1, except that the temperature of the heat treatment was set to 100 ° C. when the laminate was produced.
  • Example 1-1 A polarizing film was formed on the resin substrate in the same manner as in Example 1-1, except that no heat treatment was performed when the laminate was produced.
  • Example 1-2 A polarizing film was formed on the resin substrate in the same manner as in Example 1-1 except that the temperature of the heat treatment was set to 50 ° C. when the laminate was produced.
  • Example 1-3 A polarizing film was formed on the resin substrate in the same manner as in Example 1-1 except that the temperature of the heat treatment was set to 55 ° C. when the laminate was produced.
  • Example 2-1 A polarizing film was formed on the resin substrate in the same manner as in Example 2-1, except that the temperature of the heat treatment was set to 55 ° C. when the laminate was produced.
  • the two polarizing plates were arranged so that the absorption axes thereof were orthogonal to each other, and the extending direction of the laminate was arranged to be orthogonal to the absorption axis of the lower polarizing plate.
  • (III) as shown in FIG. 5 (b), light was irradiated from below with a commercially available polarizing plate superimposed on the laminate (sample) and observed visually from above. In that case, it arrange
  • the evaluation criteria shown in Table 1 are as follows.
  • the film thickness unevenness, slow axis unevenness and absorption axis unevenness of the PVA resin layer were suppressed at all time points. Also, the appearance was excellent. In Examples 1-5 and 2-3, the occurrence of wrinkles was visually confirmed. This is considered to be due to heat wrinkles generated in the resin base material by the heat treatment.
  • the polarizing film of the present invention is suitably used for an image display device, for example.
  • LCD TVs, LCDs, mobile phones, digital cameras, video cameras, portable game machines, car navigation systems, copy machines, printers, fax machines, watches, microwave ovens, etc., anti-reflection plates for organic EL devices Etc. are suitably used.

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  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Optics & Photonics (AREA)
  • Nonlinear Science (AREA)
  • Mathematical Physics (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Chemical & Material Sciences (AREA)
  • Shaping By String And By Release Of Stress In Plastics And The Like (AREA)
  • Polarising Elements (AREA)
  • Laminated Bodies (AREA)
  • Application Of Or Painting With Fluid Materials (AREA)
  • Coating Of Shaped Articles Made Of Macromolecular Substances (AREA)
  • Engineering & Computer Science (AREA)
  • Plasma & Fusion (AREA)
  • Thermal Sciences (AREA)

Abstract

L'invention concerne un stratifié qui permet la formation d'un film polarisant présentant une performance uniforme. Un procédé de production d'un stratifié selon la présente invention comprend, dans l'ordre suivant, une étape de chauffage d'une base de résine (11) à une température qui est inférieure à la température de transition vitreuse (Tg) de la base de résine (11) de 15 °C ou plus et une étape de formation d'une couche de résine d'alcool polyvinylique (12) sur la base de résine (11).
PCT/JP2015/053071 2014-07-16 2015-02-04 Procédé de production d'un stratifié WO2016009663A1 (fr)

Priority Applications (5)

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KR1020177004312A KR102450433B1 (ko) 2014-07-16 2015-02-04 적층체의 제조 방법
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KR1020217007420A KR102450442B1 (ko) 2014-07-16 2015-02-04 적층체의 제조 방법
KR1020227020962A KR102580445B1 (ko) 2014-07-16 2015-02-04 적층체의 제조 방법
CN201580038875.3A CN106537196B (zh) 2014-07-16 2015-02-04 层叠体的制造方法

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CN105729962B (zh) * 2014-12-24 2018-01-05 住友化学株式会社 偏振膜、偏振片和偏振膜的制造方法
CN105223639B (zh) * 2015-11-16 2019-06-25 云南云天化股份有限公司 薄型聚乙烯醇偏光膜的制备方法
CN107219583B (zh) * 2016-03-22 2021-12-03 住友化学株式会社 偏振片、偏振膜以及偏振片的制造方法
JP2017173793A (ja) * 2016-03-22 2017-09-28 住友化学株式会社 偏光子、偏光フィルム、および偏光子の製造方法

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JP2012058383A (ja) * 2010-09-07 2012-03-22 Nitto Denko Corp 薄型偏光膜の製造方法
JP2014074786A (ja) * 2012-10-04 2014-04-24 Nitto Denko Corp 延伸積層体の製造方法

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JP4661504B2 (ja) * 2005-09-29 2011-03-30 富士フイルム株式会社 熱可塑性樹脂フィルム及びその製造方法
JP2008122502A (ja) * 2006-11-09 2008-05-29 Sumitomo Chemical Co Ltd 偏光板の製造方法
JP4651054B2 (ja) * 2008-04-11 2011-03-16 日東電工株式会社 偏光子の製造方法およびそれに用いる湿式延伸装置
JP4868266B2 (ja) * 2010-03-31 2012-02-01 住友化学株式会社 積層フィルムの製造方法および偏光板の製造方法
JP2012003173A (ja) * 2010-06-21 2012-01-05 Sumitomo Chemical Co Ltd 偏光フィルム及び偏光板の製造方法
JP6045826B2 (ja) * 2012-07-09 2016-12-14 住友化学株式会社 偏光板の製造方法

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JP2012058381A (ja) * 2010-09-07 2012-03-22 Nitto Denko Corp 薄型偏光膜の製造方法
JP2012058383A (ja) * 2010-09-07 2012-03-22 Nitto Denko Corp 薄型偏光膜の製造方法
JP2014074786A (ja) * 2012-10-04 2014-04-24 Nitto Denko Corp 延伸積層体の製造方法

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KR102450442B1 (ko) 2022-10-06
CN109910410A (zh) 2019-06-21
JP2016028875A (ja) 2016-03-03
KR20220093005A (ko) 2022-07-04
TW201919909A (zh) 2019-06-01
CN109910410B (zh) 2021-01-08
KR20220092637A (ko) 2022-07-01
KR102450433B1 (ko) 2022-10-05
CN106537196B (zh) 2020-02-07
KR20170039191A (ko) 2017-04-10
CN106537196A (zh) 2017-03-22
KR20210031544A (ko) 2021-03-19
TWI693156B (zh) 2020-05-11
KR102580445B1 (ko) 2023-09-21

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