KR20210074319A - laminate - Google Patents

Abstract

According to the present invention, the substrate, the transfer layer, and the adhesive layer are included in this order, the transfer layer and the adhesive layer are adjacent to each other, the area of the transfer layer is larger than the area of the adhesive layer, and the film thickness of the transfer layer has an in-plane distribution, the adhesive layer A laminate is provided, wherein the film thickness t1 of the transfer layer at the position P1 where the end of the transfer layer is in contact with the transfer layer is smaller than the film thickness t2 of the transfer layer at the position P2 inside it.

Description

laminate

The present invention relates to a laminate comprising a transfer layer and an adhesive layer. More specifically, the present invention relates to a laminate comprising, for example, a transfer layer useful as an optical film that can be suitably used in a liquid crystal display device and the like and an adhesive layer.

DESCRIPTION OF RELATED ART In recent years, display apparatuses, such as a liquid crystal display device, have progressed rapidly in thickness reduction and enlargement, and thickness reduction of members including an optical film is progressing for the purpose of securing designability and suppressing the optical non-uniformity malfunction of a display apparatus according to environmental change. is becoming

For example, in a polarizing plate, which is an essential member of a liquid crystal display device, when the polarizing plate is stretched and contracted due to a change in environmental humidity, the liquid crystal panel to which the polarizing plate is bonded is bent, and light non-uniformity occurs due to contact between the panel and the backlight member is becoming

In order to solve this problem, the system (patent document 1) of using a low moisture permeability optical film, the system (patent document 2, patent document 3) etc. which suppress the force which generate|occur|produces by the dimensional change of an optical film are proposed.

Moreover, the method (patent document 4) etc. which reduce the curvature of a panel by thinning using a transferable optical film are proposed.

On the other hand, for the purpose of improving the quality of the transfer layer, a method of multi-layering the non-transfer region (Patent Document 5), a transfer method of peeling the substrate after bending the transfer material in advance (Patent Document 6), and the like have been proposed.

Patent Document 1: Japanese Patent Application Laid-Open No. 2015-007768 Patent Document 2: Japanese Patent Application Laid-Open No. 2014-095880 Patent Document 3: International Publication No. 2017/138551 Patent Document 4: Japanese Patent Application Laid-Open No. 2017-215562 Patent Document 5: Japanese Patent Application Laid-Open No. 2003-103997 Patent Document 6: Japanese Patent Application Laid-Open No. 10-067199

The transferable optical film disclosed in Patent Document 4 exhibits an excellent effect, but in recent years, further improvement in performance has been demanded, and in particular, substrate releasability (performance capable of stably peeling the transfer layer from the substrate) and There is room for consideration regarding the reduction of defects.

Moreover, in the method disclosed by patent document 5, when producing a long laminated body, a conveyance position shift and the position shift resulting from the dimensional change of each material in a wide laminated body generate|occur|produce, and base material peelability is improved I found out that there are cases where it doesn't work. Moreover, it turned out that the method disclosed by patent document 6 may not be applicable due to the structural limitation of a production apparatus.

An object to be solved by the present invention is to provide a laminate including a transfer layer and an adhesive layer having good substrate releasability and fewer defects.

In order to improve the base material releasability, an in-plane distribution is provided in the film thickness of the transfer layer, and the film thickness of the transfer layer at the position (P1) in contact with the end of the adhesive layer is set at a position (P2) inside it. By making it thinner than the film thickness of the transfer layer in ), it discovered that the said subject could be solved, and came to complete this invention.

Accordingly, the present invention, which is a specific means for solving the above problems, is as follows.

<1>

A substrate, a transfer layer, and an adhesive layer are included in this order, the transfer layer and the adhesive layer are adjacent to each other, the area of the transfer layer is larger than the area of the adhesive layer, and the film thickness of the transfer layer has an in-plane distribution, so that the end of the adhesive layer and the transfer layer A laminate characterized in that a film thickness (t1) of the transfer layer at this contacting position (P1) is smaller than a film thickness (t2) of the transfer layer at a position (P2) inside it.

<2>

The laminate according to <1>, wherein a difference between the adhesive force (fa1) between the transfer layer and the substrate in P1 and the adhesion force (fa2) between the transfer layer and the substrate in P2 is less than 3 N/25 mm.

<3>

The laminate according to <1> or <2>, wherein the main material of the transfer layer is a thermoplastic resin.

<4>

The laminate according to any one of <1> to <3>, wherein the laminate is a long laminate.

<5>

The laminate according to <3>, wherein the main material of the transfer layer is a vinyl aromatic resin or a cyclic olefin resin.

<6>

The laminate according to any one of <1> to <4>, wherein the main material of the transfer layer is a curable composition.

<7>

The laminate according to any one of <1> to <6>, wherein an optical film is adjacent to a surface of the adhesive layer opposite to the transfer layer.

<8>

The laminate according to <7>, wherein the optical film is a polarizing film or a protective film of the polarizing film.

<9>

The laminate according to <7>, wherein the optical film is a retardation film.

<10>

A liquid crystal display device comprising a liquid crystal cell and the laminate according to any one of <1> to <9>.

<11>

An organic electroluminescent display device comprising an organic electroluminescent element and the laminate according to any one of <1> to <9>.

ADVANTAGE OF THE INVENTION According to this invention, the laminated body containing the transfer layer with few defects and the adhesive layer with favorable base material peelability can be provided.

BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic diagram which shows an example of the laminated body of this invention, and an example of a to-be-transferred body.
It is a schematic diagram which shows the edge part vicinity of the adhesive layer of an example of the laminated body of this invention.

The content of the present invention will be described in detail. Although description of the structural requirements described below may be made based on the typical embodiment of this invention, this invention is not limited to such an embodiment. However, in the present specification, "~" is used in the meaning including the numerical value described before and after it as a lower limit and an upper limit.

<<Warrior Layer>>

The transfer layer in this invention is demonstrated.

In the laminate of the present invention, the transfer layer is adjacent to the adhesive layer, and typically, the adhesive layer of the laminate of the present invention is adhered to another article (transfer object), or the transfer object and the transfer layer of the present invention are adhered to each other. By laminating the substrate with an adhesive (adhesive layer) interposed therebetween (see Fig. 1) and peeling the substrate of the laminate of the present invention, the transfer layer is peeled from the substrate and transferred onto another article together with the adhesive layer.

At this time, if the force required to tear the transfer layer is less than the force required to peel the transfer layer from the substrate, the inner side of P1 is peeled between the transfer layer and the substrate, and the outer side of P1 is that the transfer layer is on the substrate side. Since it remains in the state, for example, a problem such as breakage of the transfer layer in a subsequent step does not occur, and defects can be reduced, which is preferable.

<Thickness>

The transfer layer of the present invention has an in-plane distribution of film thickness, and when the transfer layer and the adhesive layer are laminated, the film thickness (t1) of the transfer layer at the position (P1) where the end of the adhesive layer and the transfer layer can be in contact is , which is thinner than the film thickness t2 of the transfer layer at the position P2 inside it. Here, the "inside position (P2)" is typically a position where the adhesive layer and the transfer layer are in contact, and indicates a position closer to the center of the adhesive layer than P1 (see Figs. 1 and 2).

Base material peelability can be improved by reducing the film thickness of P1 vicinity and making a transfer layer easy to tear. Specifically, the ratio (t1/t2) of t1 to t2 is less than 1, preferably 0.9 or less, more preferably 0.8 or less, still more preferably 0.7 or less, and most preferably 0.6 or less. By making t1/t2 small, the frequency of tearing from an unexpected position can be reduced, base material peelability becomes favorable, and the defect of a laminated body can be reduced.

t1 is set within the range satisfying the above t1/t2 ratio, preferably 0.05 to 7.0 μm, more preferably 0.2 to 4.5 μm, still more preferably 0.5 to 4.0 μm, and most preferably 0.7 to 3.5 μm Do. If t1 is 0.05 µm or more, it is preferable because the frequency of occurrence of defects such as perforation in the transfer layer near P1 is suppressed.

Further, the transfer layer in the laminate of the present invention has a region having a film thickness of t1 from the position P1 in contact with the end portion of the adhesive layer to the end portion of the transfer layer (also referred to as a “P1 region”; see Fig. 2). it is preferable The P1 region may include a region to be transferred (a region in contact with the adhesive layer (also referred to as a “transfer region”)) and a non-transfer region as shown in Fig. 1, but the transfer region in the P1 region is, for example, When it does not have the film thickness for exhibiting desired performance as an optical film as a product, it may be handled as a non-product part. From such a viewpoint, the width of the region (region P1) in which the film thickness is t1 (region P1) is preferably narrow from the viewpoint of increasing the product yield. It is preferable to set in consideration of the dimensional change of the to-be-transferred object. For example, when the laminate of the present invention is a long laminate, P1 is in the vicinity of both ends in the width direction, and the width of t1 is usually 3 to 50 mm on one side in consideration of the conveyance position accuracy in the width direction of the web. And, 5-30 mm is more preferable, and 10-20 mm is more preferable. In the case where the dimensional change due to temperature or humidity of the transfer layer or the transfer target layer has a dominant influence on the positional accuracy, it is preferable to add the width due to the dimensional change of the material to the width of t1 considering the conveying positional accuracy ( In this case, it is preferable to determine the additional amount of the width of t1 in consideration of the dimensional change rate, and it is preferable to increase or decrease the additional amount according to the width of the material).

It is preferable that the transfer layer in the laminate of the present invention has a region having a film thickness of t2 (also referred to as a "P2 region"; see Fig. 2). t2 is typically, as shown in Fig. 1, the film thickness of the transfer region serving as the product portion, preferably satisfying other performance such as, for example, mechanical strength, preferably 0.1 to 10 μm, 0.5 to 7.0 micrometers is more preferable, 1.0-6.0 micrometers is still more preferable, and 1.5-5.5 micrometers is the most preferable. If t2 is 0.1 μm or more, it is preferable from the viewpoint of ensuring other performance of the transfer region used as a product, and if it is 10 μm or less, it is preferable from the viewpoint of substrate releasability and thickness reduction of the laminate.

As a specific method for partially thinning t1, when the transfer layer is a coating film, before the drying of the coating film is finished, a method of scraping by providing a plate-shaped jig for removing the coating film in the vicinity of P1, or a wire bar and a wire bar on the coating film in the vicinity of P1 It can be carried out by pressing the same jig to make it thin. When the jig|tool like a wire bar is pressed, the nonuniformity of a film thickness may generate|occur|produce in the width direction, In that case, t1 is evaluated by the thinnest part. Moreover, there exists a method of realizing by forming a transfer layer by multilayer coating, and changing the application|coating width of the 1st layer and 2nd layer. In this case, the material of the wide layer and the narrow layer may be changed, and the wide layer may be made of a material prone to tearing.

As another method of partially thinning t1, when the transfer layer is an amorphous polymer, the temperature applied to the region near P1 is less than the Tg of the transfer layer, and the temperature applied to the region P2 is higher than the Tg of the transfer layer. Thus, there is a method in which the plane orientation of the region near P1 is advanced and the plane orientation of the region P2 is suppressed. Further, when the transfer layer is a crystalline polymer, there is a method in which the region near P1 is partially heated to a crystallization temperature or higher.

<Adhesive force between the transfer layer and the substrate>

In the multilayer film of the transfer layer and the substrate of the present invention, in order to stably peel the substrate, the in-plane distribution of the adhesive force between the transfer layer and the substrate is preferably small, and the difference between the adhesive force in P1 and the adhesive force in P2 is , It is preferable that it is less than 3N/25mm, It is more preferable that it is less than 1N/25mm, It is more preferable that it is less than 0.5N/25mm.

0.001-5N/25mm is preferable, as for the adhesive force in P1, 0.01-3N/25mm is more preferable, 0.1-1N/25mm is still more preferable, 0.15-0.8N/25mm is the most preferable. If it is 0.001 N/25 mm or more, an unexpected peeling failure in other than the peeling process of the base material can be prevented, and if it is 5 N/25 mm or less, peeling failure in the peeling process (for example, zipping or cracking of the transfer layer) can prevent

In addition, the higher the adhesive force at P2, the better the substrate releasability, but if the in-plane distribution of the adhesive force is large, wrinkles or tugging may occur on the substrate or the transfer target, and the substrate peelability may sporadically deteriorate. It is preferable that P2 is set so that the in-plane distribution of adhesive force may fall within the above-mentioned range. That is, when the base material of the transfer layer is peeled off, the in-plane distribution of the adhesive force between the transfer layer and the base material is preferably small in order to avoid wrinkling or pulling on the base material or the transfer target, and for stable peeling.

When the transfer layer of the present invention is formed by a coating method, the adhesive force between the transfer layer and the substrate can be controlled by adjusting the material of the transfer layer, the material of the substrate, internal distortion of the transfer layer, and the like.

In the present specification, the adhesive force of the transfer layer and the substrate is, after bonding and fixing the transfer layer of the multilayer film cut to a width of 25 mm and a length of 80 mm to a glass substrate through an acrylic adhesive sheet, a tensile tester (A and Co., Ltd.) · Using a DJ RTF-1210), hold the substrate at one end (one side of 25 mm in width) in the longitudinal direction of the test piece, in an atmosphere with a temperature of 23°C and a relative humidity of 60%, crosshead speed (chuck movement speed) 300 mm/min and evaluated by a 90° peel test based on JIS K 6854-1: 1999 "Adhesive - Peel Adhesive Strength Test Method - Part 1: 90 Degree Peel".

<Breaking Discipleship>

Although the breaking elongation of the transfer layer of this invention is not specifically limited, It is preferable that it is 0.1 to 10 %, 0.3 to 7 % is more preferable, 0.5 to 5 % is still more preferable. If the elongation at break of the transfer layer is 0.1% or more, it is preferable because cracks are less likely to occur in the transfer layer, and if it is 10% or less, since the base material peelability is improved, it is preferable. The elongation at break of the transfer layer is in the state of a multilayer film of the transfer layer and the substrate, and the transfer layer is arranged on the outside of the bending, and cracks do not occur by the cylindrical mandrel method according to JIS K5600-5-1, from the diameter of the transfer layer. It is obtained by calculating the distortion.

<modulus of elasticity>

Although the elastic modulus of the transfer layer of this invention is not specifically limited, 0.5-6.0 GPa is preferable, 1.5-4.5 GPa is more preferable, 2.0-3.5 GPa is still more preferable. If the elastic modulus of a transfer layer is 0.5 GPa or more, since base material peelability improves, it is preferable.

In this specification, the elastic modulus (tensile elastic modulus) of a transfer layer can be measured using the film which made the film thickness thick so that self-support can be maintained as needed. For the elastic modulus of the film, the measurement direction is the film longitudinal direction, the film is cut so that the measurement portion has a size of 10 cm x 1 cm, and the humidity is controlled at 25 ° C. and 60% relative humidity for 24 hours, and Toyo Baldwin Co., Ltd. universal tension Using a testing machine "STM T50BP", the stress at 0.1% elongation and 0.5% elongation at a tensile rate of 10%/min is measured, and the elastic modulus is calculated from the inclination.

<Glass transition temperature (Tg)>

The glass transition temperature (Tg) of the transfer layer of the present invention or the resin used for the transfer layer is not particularly limited. Tg is, for example, after humidity control at 25°C and 10% relative humidity for 24 hours, the sample is sealed in a measurement pan, and using a differential scanning calorimeter "DSC6200" manufactured by Seiko Instruments Co., Ltd., at 20°C/min. From the thermogram obtained by heating up, it can obtain|require as the intersection temperature of the tangent at a baseline and an inflection point.

<Other characteristics>

The characteristic values other than the above of the transfer layer of the present invention are not particularly limited, and performance equivalent to that of a general known transfer film can be appropriately mounted, and it is preferable that the performance required for a general optical film is appropriately mounted. . Specific characteristic values include haze, light transmittance, spectral characteristics, retardation, and wet-heat durability of retardation for display characteristics, and dimensional change rate due to humidity, temperature, and wet-heat thermostat related to mechanical characteristics and processing aptitude, Equilibrium moisture absorption, moisture permeability, contact angle, etc. are mentioned.

<Layer composition>

A single layer may be sufficient as the transfer layer of this invention, and it may have a laminated structure of two or more layers. In the case of a laminated structure of two or more layers, the width of each layer constituting the transfer layer may be different, for example, in order to provide a film thickness difference between t1 and t2, a laminated structure of two or more layers may be adopted. Moreover, it is also possible to laminate other functions by laminating functional layers.

<Main ingredient>

The main material constituting the transfer layer of the present invention is not particularly limited, and a cured composition of a thermoplastic resin or a composition containing a reactive monomer, etc. can be suitably used.

Note that the main material constituting the transfer layer is a component with the highest content (based on mass) among the components contained in the transfer layer.

・Thermoplastic resin

The thermoplastic resin constituting the transfer layer of the present invention is not particularly limited, but from the viewpoint of improving brittleness and elastic modulus, it is preferable to include a polar structure, for example, to strengthen the interaction between polymer molecules, and crystal A polymer may be sufficient, an amorphous polymer may be sufficient, and a liquid crystalline polymer may be sufficient. Specific examples include known vinyl aromatic resins (styrene-based resins, divinylbenzene-based resins, vinylpyridine-based resins, etc.), cyclic olefin-based resins, cellulose-based resins (cellulose acylate resins, cellulose ether resins, etc.), poly Vinyl resins other than ester-type resin, polycarbonate-type resin, vinyl aromatic resin, polyimide-type resin, polyarylate-type resin, etc. are mentioned. Among these, styrene resin and cyclic olefin resin are preferable from a hydrophobic viewpoint of a material, and a cellulose acylate resin is preferable from a brittle viewpoint.

Regarding the vinyl aromatic resin, specifically, paragraphs [0035] to [0041] of Japanese Patent Application Laid-Open No. 2017-167514 describe a vinyl aromatic resin and a styrene-based resin, and can be appropriately used.

About cyclic olefin resin, there exists description in Paragraph [0047] of Unexamined-Japanese-Patent No. 2017-215562 - [0049] specifically, It can use suitably.

Cellulose acetate, cellulose acetate propionate, cellulose propionate, cellulose acetate butyrate, cellulose acetate propionate butyrate, cellulose acetate benzoate etc. are mentioned as an example of cellulose acylate resin. Among them, cellulose acetate and cellulose acetate propionate having microcrystalline properties and excellent in mechanical strength and thermal dimensional stability are preferable.

Examples of the polycarbonate resin include a polycarbonate, a polycarbonate containing a structural unit in which bisphenol A is modified with fluorene, and a polycarbonate containing a structural unit in which bisphenol A is modified with 1,3-cyclohexylidene.

Polyethylene, polypropylene, polystyrene, polyvinylidene chloride, polyvinyl alcohol etc. are mentioned as an example of a vinyl resin.

The number of thermoplastic resins which comprise the transfer layer of this invention may be one, and may contain two or more types. Moreover, when a transfer layer is formed in multilayer, the thermoplastic resin of each layer may be different.

・Curable composition

As another aspect of the transfer layer of the present invention, a known curable composition can be used. A curable composition is not specifically limited, A well-known acrylic monomer, an epoxy monomer, etc. are included. Moreover, you may mix and implement a curable composition with the thermoplastic resin mentioned above suitably.

With respect to the reactive monomer, specifically, a compound having a cyclic aliphatic hydrocarbon group and an unsaturated double bond group described in paragraphs [0016] to [0044] of JP 2014-170130 A, a compound having a fluorene ring and an unsaturated double bond group, Japan The polyfunctional monomers described in Paragraphs [0109] to [0133] of Unexamined-Japanese-Patent No. 2013-231955, etc. can be used suitably. Moreover, in order to provide water glue adhesiveness with a polarizing film, the boronic acid monomer described in WO2015/053359 can also be used together.

・Polymerization initiator

Said curable composition can contain a well-known polymerization initiator, and a photoinitiator is preferable.

Examples of the photopolymerization initiator include acetophenones, benzoins, benzophenones, phosphine oxides, ketals, anthraquinones, thioxanthones, azo compounds, peroxides, 2,3-dialkyldione compounds, disulfides compounds, fluoroamine compounds, aromatic sulfoniums, loffin dimers, onium salts, borate salts, active esters, active halogens, inorganic complexes, coumarins, and the like. The specific example of a photoinitiator, a preferable aspect, a commercial item, etc. have description in paragraphs [0133] - [0151] of Unexamined-Japanese-Patent No. 2009-098658, and can be used suitably.

"Advanced UV curing technology" {Kijutsu Joho Kyokai Co., Ltd.} (1991), p. 159, and "Ultraviolet curing system" by Kiyomi Kato (Heisei 1st year, published by Sogo Kijutsu Center), p. Various examples are also described in 65-148 and are useful in the present invention.

<Additives>

A well-known additive can be mixed suitably with the transfer layer of this invention. As known additives, low molecular weight plasticizers, leveling agents, oligomer-based additives, polyester-based additives, retardation regulators, microparticles, ultraviolet absorbers, deterioration inhibitors, peeling accelerators, visible light absorbers (pigments), infrared absorbers, antioxidants, fillers, compatibilizers agent, a polarization degree improver, a discoloration inhibitor, etc. are mentioned.

Generally, when an addition amount increases, these additives become easy to tear a transfer layer in many cases, and can also be used for the purpose of controlling the tearing easiness of a transfer layer. Moreover, it can also be used for the purpose of controlling the adhesive force of a transfer layer and a base material.

When the transfer layer is formed in multiple layers, the type and amount of the additive in each layer may be different.

・fine particles

Fine particles can be added to the transfer layer of the present invention for the purpose of controlling the easiness of tearing, slipping properties, preventing blocking, and the like. It is preferable that the addition amount of microparticles|fine-particles is added in the range which does not impair the transparency of a transfer layer. As the fine particles, the surface is covered with small number of groups, a silica (silicon dioxide, SiO ₂₎ which takes the aspect of secondary particles is preferably used. In addition, in fine particles, with or instead of silica, titanium dioxide, aluminum oxide, zirconium oxide, calcium carbonate, talc, clay, calcined kaolin, calcined calcium silicate, hydrated calcium silicate, aluminum silicate, magnesium silicate, calcium phosphate, etc. of fine particles may be used. As a commercial product, the microparticles|fine-particles are mentioned a brand name R972, NX90S (all are Nippon Aerosil Co., Ltd. product), etc. are mentioned.

・Polyester Additives

A known polyester-based additive may be appropriately mixed with the transfer layer of the present invention for the purpose of controlling the adhesive force between the transfer layer and the substrate. The effect of increasing the adhesion between the transfer layer and the substrate by adding a compound such that the difference in surface energy between the transfer layer and the substrate is small, a compound containing a component having a glass transition temperature lower than room temperature, or a compound having permeability to the substrate there is

The polyester-based additive is specifically described in paragraphs [0075] to [0082] of JP2013-231955A, and can be appropriately used.

・Leveling agent

A well-known leveling agent (surfactant) can be mixed suitably with the transfer layer of this invention. Although a conventionally well-known compound is mentioned as a leveling agent, A fluorine-containing surfactant is especially preferable. Specifically, for example, the compounds described in Paragraph Nos. [0028] to [0056] in Japanese Patent Application Laid-Open No. 2001-330725 are exemplified.

・Pigment

A dye can be suitably added to the transfer layer of this invention. The optimal absorption wavelength band of the dye is suitably changed depending on the design of the display device, but for example, a dye having a main absorption wavelength band at a wavelength of 460 to 520 nm (hereinafter referred to as dye A), or a main absorption at a wavelength of 560 to 620 nm. A dye having an absorption wavelength band (hereinafter referred to as dye B) is preferable. Further, the transfer layer of the present invention may contain a dye other than the dye A and the dye B.

The dye A is not particularly limited as long as it has a main absorption wavelength band at a wavelength of 460 to 520 nm, and various dyes can be used. This dye A exhibits fluorescence in many cases.

In the present invention, having a main absorption wavelength band at a wavelength of XX to YY nm means that a wavelength showing a maximum absorption wavelength in a visible light absorption spectrum (wavelength range 380 to 750 nm) exists in a wavelength range of XX to YY nm. . Therefore, if this wavelength is within the wavelength region, the entire absorption band including this wavelength may be within the wavelength region, or may be spread out of the wavelength region. Moreover, when two or more maximum absorption wavelengths exist, the maximum absorption wavelength which shows the absorbance which is not the highest may exist outside the wavelength range XX-YYnm. In addition, when a plurality of wavelengths exhibiting the maximum absorption wavelength exist, one of them may exist in the wavelength region.

Specific examples of the dye A include, for example, pyrrole methine (PM), rhodamine (RH), boron dipyrromethene (BODIPY), and squarine (SQ). of each dye. For example, commercial items, such as FDB-007 (a brand name, merocyanine type dye, Yamada Chemical Co., Ltd. make), can also be used suitably as dye A.

The dye B is not particularly limited as long as it has a main absorption wavelength band at a wavelength of 560 to 620 nm, and various dyes can be used. This dye B has weaker fluorescence than dye A, or does not show fluorescence in many cases.

Specific examples of the dye B include dyes of tetraaza porphyrin (TAP), squarin, and cyanine (CY). In addition, commercially available products such as PD-311S (trade name, tetraazaporphyrin-based dye, manufactured by Yamamoto Chemical Co., Ltd.) and FDG-006 (trade name, tetraazaporphyrin-based dye, manufactured by Yamada Chemical Industries, Ltd.) can also be preferably used as dye B. .

・Fade inhibitor

To the transfer film of the present invention, an anti-fading agent can be added as appropriate. As the fading inhibitor used in the present invention, the antioxidant described in paragraphs [0143] to [0165] of International Publication No. 2015/005398, the radical scavenger described in [0166] to [0199], and [0205] to [ 0206] can be used.

<<Report>>

It is preferable that the film thickness of the base material used in order to form a transfer layer by a coating method is 5-100 micrometers, 10-75 micrometers is more preferable, 15-55 micrometers is still more preferable. A film thickness of 5 µm or more is preferable because it is easy to ensure sufficient mechanical strength, and failures such as curling, wrinkling, and buckling are unlikely to occur. Moreover, there exists a tendency for base material peelability to become favorable that a film thickness is 100 micrometers or less, and it is preferable. Although the mechanism for which the film thickness of a base material becomes the thin film thickness of a base material favorable is unknown, since the peeling angle of a base material approaches an acute angle, it is thought that it is because a transfer layer becomes easy to tear.

The surface energy of the substrate is not particularly limited, but by adjusting the relationship between the surface energy of the material of the transfer layer or the coating solution and the surface energy of the surface of the substrate on which the transfer layer is formed, the transfer layer and the substrate are Adhesion between the two can be adjusted. When the surface energy difference is made small, the adhesive force tends to rise, and when the surface energy difference is enlarged, the adhesive force tends to fall, and it can set suitably.

The surface energy of the substrate can be calculated using the Owens method from the contact angle values of water and methylene iodide. For the measurement of the contact angle, for example, DM901 (manufactured by Kyowa Chemical Co., Ltd., contact angle meter) can be used.

Although the surface energy of the side which forms the transfer layer of a base material is not specifically limited, It is preferable that it is 41.0-48.0 mN/m, and it is more preferable that it is 42.0-48.0 mN/m. If the surface energy is 41.0 mN/m or more, it is preferable because the uniformity of the film thickness of the transfer layer can be improved, and if it is 48.0 mN/m or less, it is preferable because it is easy to control the peeling force between the transfer layer and the substrate in an appropriate range. Do.

Further, the surface asperity of the substrate is not particularly limited, but the relationship between the surface energy, hardness, and surface unevenness of the transfer layer surface and the surface energy and hardness of the surface opposite to the side on which the transfer layer of the substrate is formed Depending on the properties, for example, it can be adjusted for the purpose of preventing adhesion failure in the case of storing the multilayer film of the present invention in the form of a long roll. When the surface unevenness is increased, adhesion failure tends to be suppressed. When the surface unevenness is decreased, the surface unevenness of the transfer layer tends to decrease and the haze of the transfer layer tends to be small, which can be appropriately set.

As such a base material, a well-known raw material and a film can be used suitably. Specific examples of the material include a polyester-based polymer, an olefin-based polymer, a cycloolefin-based polymer, a (meth)acrylic-based polymer, a cellulose-based polymer, and a polyamide-based polymer. Moreover, in order to adjust the surface property of a base material, it can surface-treat suitably. In order to decrease the surface energy, for example, corona treatment, room temperature plasma treatment, saponification treatment, etc. can be performed, and in order to increase the surface energy, silicon treatment, fluorine treatment, olefin treatment, etc. can be performed.

<<Production of the Warrior Layer>>

The transfer layer of the present invention can be produced by a method of forming a coating layer on a substrate by a known method, and when the main material of the transfer layer is a thermoplastic resin, according to the known solution film forming method and melt extrusion method, co-cast (共流延), co-extrusion, stretching, etc. may be combined as appropriate.

In the coating method, a material for a transfer layer is applied to a film, which is a substrate, and a coating layer is formed. In order to control the adhesiveness with a coating layer to the base material surface, you may apply|coat a mold release agent etc. in advance suitably. After the coating layer is laminated with the polarizing layer through an adhesive or pressure-sensitive adhesive in a post-process, the base material may be peeled for use. In addition, in a state in which a polymer solution or a coating layer is laminated on a substrate, the optical properties and mechanical properties can be adjusted by appropriately stretching each substrate.

The solution film forming method prepares a solution in which the material of the transfer layer is dissolved in an organic solvent or water, and after appropriately performing a concentration step, a filtration step, and the like, it is uniformly cast on a support. Next, the semi-dried film|membrane is peeled from the support body, the both ends of the web are properly clamped with a clip etc., and the solvent is dried in a drying zone. Moreover, extending|stretching can also be performed separately during drying of a film, or after drying is complete|finished.

The solvent used for the solution of the transfer layer material is one capable of dissolving or dispersing the transfer layer material, one that tends to form a uniform planar shape in the application process and the drying process, one that can ensure liquid retention, and one having an appropriate saturated vapor pressure. It can be suitably selected from a viewpoint of things etc.

The melt extrusion method is specifically described in paragraphs [0085] to [0090] of Japanese Patent Application Laid-Open No. 2017-215562, and can be used appropriately.

The transfer layer is preferably subjected to a hydrophilization treatment by a known glow discharge treatment, corona discharge treatment, or alkali saponification treatment, and corona discharge treatment is most preferably used. It is also preferable to apply the method or the like disclosed in Japanese Patent Application Laid-Open No. 6-094915 or 6-118232.

Moreover, to the obtained film, a heat treatment process, a superheated steam contact process, an organic solvent contact process, etc. can be implemented as needed. Moreover, it can surface-treat and can also apply as a hard-coat film, an anti-glare film, and an antireflection film.

<<Adhesive layer>>

The material used as the adhesive layer of the present invention is not particularly limited, and a known adhesive or pressure-sensitive adhesive composition can be used.

・Curable adhesive

As the curable adhesive, an ultraviolet curable adhesive can be preferably used. Although it does not specifically limit as a kind of ultraviolet curing adhesive, It is preferable to use the epoxy-type ultraviolet curing adhesive of Unexamined-Japanese-Patent No. 2015-187744, and the acrylate type ultraviolet curing adhesive of Unexamined-Japanese-Patent No. 2015-11094. Do.

・Water-based adhesive

As the water-based adhesive, an aqueous solution of polyvinyl alcohol or polyvinyl acetal (eg, polyvinyl butyral) or latex of a vinyl-based polymer (eg, polybutyl acrylate) can be used.

・Adhesive composition

As the pressure-sensitive adhesive (adhesive), a pressure-sensitive adhesive composition can be used. Regarding the pressure-sensitive adhesive composition, specifically, the pressure-sensitive adhesive composition described in paragraphs [0106] to [0111] of JP 2017-215562 A, and the crosslinking agent described in paragraph [0124] can be appropriately used.

<Film thickness of adhesive layer>

The film thickness of the adhesive layer of the present invention is not particularly limited, but in the case of a curable adhesive, from the viewpoint of reconciling adhesiveness with a transfer target and sclerosis of adhesion, 0.1 to 10 μm, more preferably 0.5 to 5 μm, , more preferably 1 to 3 µm. Moreover, in the case of a water-based adhesive, from a viewpoint of making adhesiveness with a transfer object and drying property of an adhesive compatible, 1-1000 nm is preferable, 10-500 nm is more preferable, 30-300 nm is still more preferable.

<<Laminate>>

The transfer layer of the present invention includes a substrate, a transfer layer, and an adhesive layer in this order. The laminate of the present invention can be produced by a known method, and is laminated so that the transfer layer and the adhesive layer are adjacent to each other, and the transfer layer is wider than the adhesive layer. That is, in the laminate of the present invention, the area of the transfer layer is larger than the area of the adhesive layer. Typically, the laminate of the present invention is rectangular (it may be in the shape of a long picture) (in addition, the substrate, the transfer layer, and the adhesive layer are rectangular), and the adhesive layer can be laminated such that the end of the transfer layer in the width direction is exposed ( 1 and 2).

When the laminated body of this invention is a long laminated body, it is preferable that both the to-be-transferred object laminated|stacked through an adhesive agent, and the base material containing a transfer layer are elongate, and can be bonded together by roll-to-roll. As an example of a laminated body in FIG. 1, the schematic diagram in case the laminated body of this invention is a long laminated body is shown.

The laminate of this invention is excellent from a viewpoint of base material peelability and a defect. Therefore, by using the laminated body of this invention, the laminated|multilayer film of the transfer layer and adhesive layer useful as an optical film used, for example for a liquid crystal display device etc. can be provided with favorable yield. Moreover, by using the laminated body of this invention, light nonuniformity is hard to generate|occur|produce and it becomes possible to provide the liquid crystal display device excellent in reliability.

<Polarizing film>

A polarizing film can also be arrange|positioned on the opposite side to the transfer layer of the adhesive layer of this invention. As a polarizing film used preferably, the thing etc. which immersed and extended|stretched a polyvinyl alcohol film in iodine solution can be used, for example. The transfer layer of this invention can be bonded together with respect to the single side|surface or both surfaces of a polarizing film via the adhesive layer mentioned above.

<Peeling of base material of transfer layer>

The process after producing the laminated body of this invention WHEREIN: It has the process of peeling and removing a base material from a transfer layer. Peeling and removal of the base material can be carried out, for example, in the same manner as in the peeling step of a separator (release film) used for a normal pressure-sensitive adhesive, and the timing of peeling is the following step or a separate step after being wound up in a roll shape, etc. , can be performed at any time.

<Antistatic layer>

An antistatic layer may be further laminated on the laminate including the transfer layer of the present invention. The antistatic layer is not particularly limited as long as it contains an antistatic agent, but from the viewpoint of obtaining good antistatic performance, the elastic modulus of the layer is preferably less than 1 GPa, more preferably 0.1 GPa or less, and still more preferably 0.05 GPa or less.

Specific examples thereof include a pressure-sensitive adhesive composition containing an antistatic agent, and for example, the antistatic agent described in paragraphs [0112] to [0122] of JP 2017-215562 A, and an antistatic agent-containing pressure-sensitive adhesive composition , can be used appropriately. The antistatic layer may be formed by, for example, applying an antistatic agent-added pressure-sensitive adhesive composition to a substrate such as a release film or an optical film to have a surface resistance value of ^{about 1×10 8} to 1×10 ¹¹ Ω/cm ^{2 .} have.

<<Display device>>

The laminate of the present invention can be used for a known liquid crystal display device or an organic electroluminescent display device.

Example

Hereinafter, the present invention will be described in more detail by way of Examples. Materials, usage amounts, ratios, processing contents, processing procedures, etc. shown in the following examples can be appropriately changed without departing from the spirit of the present invention. Therefore, the scope of the present invention is not limited to the specific examples shown below.

<<Production of multilayer film>>

<Multilayer film A1>

By the method shown below, the peelable multilayer film was produced.

1) Preparation of coating solution

With the composition shown below, the coating liquid 1 for multilayer film formation was prepared.

2) Composition of Coating Solution 1

SGP-10 50.0 parts by mass

Epocross RPS-1005 48.7 parts by mass

Byron 550 1.0 parts by mass

A-19-1 0.3 parts by mass

ethyl acetate 600.0 parts by mass

The obtained coating liquid was filtered with the filter of 1 micrometer of absolute filtration precision, and the coating liquid 1S was obtained.

The materials used are shown below.

・SGP-10: polystyrene [manufactured by PS Japan]

・Epocross RPS-1005: Styrene-oxazoline copolymer [manufactured by Nippon Shokubai]

・Byron 550 [manufactured by Toyobo Co., Ltd.]

· Fluorinated copolymer (A-19-1): A polymer having the following structure. It was prepared in the same manner as in Synthesis Example 22 ([0183] to [0185]) of Japanese Patent Application Laid-Open No. 2018-005215.

[Formula 1]

3) Application of multilayer film

A commercially available polyethylene terephthalate film, Emblet S38 (film thickness 38 µm, width 1340 mm, manufactured by Unitica Corporation) was used as a base material (coating base material), and the coating liquid 1S was used. 1320 mm of coating-film width produced it so that the film thickness (t2) of width center vicinity after drying might become the value of Table 1, and multilayer film A1 was obtained. Specifically, it is a die coating method using a slot die described in JP-A-2006-122889 Example 1, and the coating is carried out under the conditions of a conveying speed of 30 m/min, and the portion at both ends 20 mm from the edge of the coating film is immediately after application. The coating film was scraped off, and the film thickness (t1) after drying was made to become the value shown in Table 1, and it dried at 105 degreeC for 30 second. After that, it was wound up.

<Multilayer film A2>

Except having changed the coating liquid of the said multilayer film A1 into the following coating liquid 2, it carried out similarly to multilayer film A1, the film was produced, and the multilayer film A2 was obtained.

2) Composition of coating solution 2

AS-70 100.0 parts by mass

SMA2000P 5.0 parts by mass

Byron 500 0.9 parts by mass

Surfactant 1 0.1 parts by mass

methyl acetate 250.0 parts by mass

acetonitrile 225.0 parts by mass

ethanol 25.0 parts by mass

The obtained coating liquid was filtered with a filter with an absolute filtration accuracy of 1 µm.

The materials used are shown below.

·AS-70: acrylonitrile-styrene copolymer resin [manufactured by Shin-Nittetsu Sumikin Chemical Co., Ltd.]

・SMA2000P [Kawahara Yuka Co., Ltd.]

・Byron 500 [manufactured by Toyobo Co., Ltd.]

- Surfactant 1: The surfactant of the following structure was used.

[Formula 2]

<Multilayer film A3>

In the coating liquid of the multilayer film A1, the addition amount of Byron 550 was changed from 1.0 parts by mass to 3.0 parts by mass, and the substrate was changed to a polyethylene terephthalate film in which 30 mm of both ends were corona-treated. was produced to obtain a multilayer film A3.

<Multilayer film A4>

The coating solution of the multi-layer film A1 is changed to the coating solution 4 below, and the coating substrate is changed to a commercially available polyethylene terephthalate film, Emblem SK50 (film thickness 50 μm, width 1340 mm, manufactured by Unitica Co., Ltd.) Moreover, except having changed the drying temperature of a coating film into 120 degreeC, it carried out similarly to multilayer film A1, the film was produced, and multilayer film A4 was obtained.

2) Composition of coating solution 4

SGP-10 85.6 parts by mass

Zyron S201A 10.0 parts by mass

Byron 550 0.10 parts by mass

pigment 1 0.33 parts by mass

Anti-Fade 1 4.0 parts by mass

Surfactant 2 0.1 parts by mass

mat agent 1 0.002 parts by mass

toluene 767.3 parts by mass

The obtained coating liquid was filtered with a filter with an absolute filtration accuracy of 1 µm.

The materials used are shown below.

・SGP-10: polystyrene [manufactured by PS Japan]

-Xylon S201A: polyphenylene ether resin [manufactured by Asahi Kasei Co., Ltd.]

・Byron 550 [manufactured by Toyobo Co., Ltd.]

- Dye 1: A dye having the following structure was used.

[Formula 3]

- Fade inhibitor 1: Surfactant of the following structure was used.

[Formula 4]

- Surfactant 2: The surfactant of the following structure was used. In the following structural formula, t-Bu means a tert-butyl group.

[Formula 5]

・Matte agent 1: Silicon dioxide fine particles, NX90S [manufactured by Nippon Aerosil Co., Ltd.]

<<Production of Polarizer>>

A polarizing plate as a laminate was produced using the multilayer film, the adhesive, and the polarizer and the opposing film.

1) Preparation of adhesive

By the method shown below, the polymeric compound, an initiator, and a sensitizer were mixed, and the adhesive composition was prepared.

2) Composition of the adhesive composition

Epiol EH-N 10.0 parts by mass

Rika Resin DME-100 20.0 parts by mass

Celoxide 2021P 70.0 parts by mass

CPI-100P 1.0 parts by mass

IRGACURE290 4.0 parts by mass

DarocurITX 0.5 parts by mass

The materials used are shown below.

・Epiol EH-N (manufactured by Nichiyu Co., Ltd.)

・Rika Resin DME-100 [made by Shin-Nippon Rika Co., Ltd.]

・Celoxide 2021P [manufactured by Daicel Co., Ltd.]

・CPI-100P [manufactured by San Apro Co., Ltd.]

・IRGACURE290 [manufactured by BASF]

・DarocurITX [manufactured by BASF]

3) Fabrication of the counter film

According to Example 1 of Unexamined-Japanese-Patent No. 2015-227458, the 60-micrometer-thick polymethyl methacrylate film was produced, and it was set as the opposing film A1.

4) Surface treatment of multilayer film

Corona-treated to the surface on the opposite side to the interface by the side of the base material of the produced multilayer film, and opposing film A1.

5) Fabrication of polarizer

According to Example 1 of Unexamined-Japanese-Patent No. 2001-141926, the circumferential speed difference was provided between two pairs of nip rolls, it extended|stretched in the longitudinal direction, and produced the polarizer with a film thickness of 15 micrometers.

6) bonding

The said surface-treated multilayer film, a polarizer, and opposing film A1 were laminated|stacked in this order, and the polarizing plate was obtained. At this time, it arrange|positions so that the surface-treated surface of the film may become a polarizer side, and the said adhesive composition was used for adhesion|attachment. Moreover, it laminated|stacked by roll-to-roll so that the absorption axis of a polarizer, a multilayer film, and the longitudinal direction of opposing film A1 might become parallel. At this time, the application width of the adhesive composition was 1300 mm, and it was laminated so that both ends of the adhesive composition came to the P1 area|region of a transfer layer. Then, using an air-cooled metal halide lamp (manufactured by Eye Graphics Co., Ltd.), it was cured by irradiating ultraviolet rays with an irradiation ^{amount of 300 mJ/cm 2 .} The obtained polarizing plate was cut and the cross section was observed with the optical microscope, and both the multilayer film side and the opposing film side confirmed that the thickness of the adhesive agent (adhesive layer) was 2.5 micrometers.

7) Peeling of the substrate

From the polarizing plate, which is the produced laminate, the substrate of the multilayer film is continuously peeled using the same device as the separation device of the separator, and with respect to the laminate after peeling the substrate, the cut state of the transfer layer in the vicinity of P1 is visually confirmed did. The result (substrate peelability) was judged as follows, and was shown in Table 1.

<Evaluation of base material peelability>

A: The substrate immediately after peeling could be stably peeled without pulling or wrinkling, and the transfer layer after peeling the substrate had no defects and was good.

B: Although pulling and wrinkling occurred sporadically in the base material immediately after peeling, the transfer layer after peeling the base material had no defects and was good.

C: The substrate immediately after peeling may have sporadically pulling or wrinkling, causing slight dust in the transfer layer after peeling the substrate, or slight cracking in the transfer layer.

D: Constant pulling or wrinkling was observed on the substrate immediately after peeling, and dust was generated in the transfer layer after peeling the substrate, or cracks occurred in the transfer layer, so the next step, the pressure-sensitive adhesive could not be applied. .

8) Coating of adhesive

The acrylic adhesive containing the antistatic agent coated on the separator was transcribe|transferred to the surface from which the base material of the produced said polarizing plate was peeled, and the process of a polarizing plate was completed.

[Table 1]

Moreover, in the comparative example 3, constant pulling was confirmed by the base material immediately after peeling, and it peeled, giving a noise.

From said Table 1, the transfer film (laminated body) of this invention was excellent in base material peelability, and was a thing with few defects. Thereby, when the laminated body of this invention was used, it turned out that products, such as a polarizing plate, can be produced with a favorable yield.

Industrial Applicability

ADVANTAGE OF THE INVENTION According to this invention, the laminated body containing the transfer layer with few defects and the adhesive layer with favorable base material peelability can be provided.

Although this invention was detailed also demonstrated with reference to the specific embodiment, it is clear for those skilled in the art that various changes and correction can be added without departing from the mind and range of this invention.

This application is based on the Japanese Patent Application (Japanese Patent Application No. 2018-243277) of an application on December 26, 2018, The content is taken in here as a reference.

Claims (4)

A substrate, a transfer layer, and an adhesive layer are included in this order, wherein the transfer layer and the adhesive layer are adjacent to each other, the area of the transfer layer is larger than the area of the adhesive layer, and there is an in-plane distribution in the film thickness of the transfer layer, A laminate characterized in that a film thickness t1 of the transfer layer at a position P1 where an end of the adhesive layer and the transfer layer are in contact is smaller than a film thickness t2 of the transfer layer at a position P2 inside it. The method according to claim 1,
The difference between the adhesive force fa1 between the transfer layer and the substrate in P1 and the adhesive force fa2 between the transfer layer and the substrate in P2 is less than 3 N/25 mm. The method according to claim 1 or 2,
A laminate in which the main material of the transfer layer is a thermoplastic resin. 4. The method according to any one of claims 1 to 3,
The laminated body is a long laminated body.

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