KR20060070564A - Recording media - Google Patents

Abstract

To provide a recording media capable of reproducing an information signal by an optical means, which effectively prevents formation of flaws on the light-incident surface thereof and has an excellent storage stability, the recording media includes a support; a recording layer capable of recording the information signal; and a light-transmitting layer capable of transmitting a light in this order, wherein the light- transmitting layer includes a light-transmitting film having a moisture expansion coefficient of 8 ppm/%RH to 62 ppm/%RH; and the light- transmitting layer has a surface having a pencil hardness of 2H or more.

Description

Recording medium {RECORDING MEDIA}

Technical field

The present invention relates to a recording medium capable of recording and reproducing information signals by optical or magnetic means, and more particularly, to a recording medium capable of reproducing information signals by optical means.

Background technology

Recording media called CD-R has been known as an additional recordable optical recording medium, which allows only one recording by laser light. CD-R has the advantage that the information recorded thereon can be reproduced by a commercially available CD player. In recent years, the demand for CD-Rs has increased with the proliferation of personal computers. In addition, as a recording medium allowing a recording capacity larger than CD-R, an additional recordable digital versatile disc (DVD-R), which is configured to record digital high definition images, has been put into practice.

As such a recordable optical recording medium, for example, a light-reflective layer containing gold or the like, a recording layer containing an organic compound, and a light transmitting layer (also called a cover layer) for protecting the recording layer Such a medium has been known, which comprises a disk-shaped support which is provided on top thereof in succession. They allow the recording and reproduction of information by irradiating them with laser light from the light-transmitting layer side. The recording of information on the additional recordable optical recording medium is carried out in such a way that the area to which the laser light of the recording layer is irradiated absorbs the light and generates heat so that deformation (for example, generation of membrane holes) occurs. On the other hand, reproduction of information involves irradiating an additional recordable optical recording medium with laser light having the same wavelength as that of the laser light used for recording, and the thermally deformed area (recorded area) and undeformed area (not recorded) of the recording layer. This is usually done by detecting a difference in reflectance between the regions).

Recently, networks such as the Internet and high-definition TV have been rapidly spreading. In addition, television broadcasting of HDTV (high definition television) has begun. In such a situation, there has been a demand for a large capacity optical recording medium capable of easily recording image information at low cost. At present, the above-described DVD-R sufficiently performs its function as a large capacity recording medium. However, the demand for large-capacity recording with higher recording density is increasing, and therefore, there is a need for the development of a recording medium capable of meeting such demand. Therefore, as an optical recording medium, a large capacity recording medium capable of recording information having a high density using short wavelength light is being developed. In particular, as the use as a medium for storing or backing up a large amount of information for a long time increases, there is a strong demand for the development of an additional recordable optical recording medium that allows recording of information only once.

In general, recording information with higher density on an optical recording medium makes the beam spot smaller through the use of shorter wavelength laser light for recording and reproducing information and the NA (Numerical) of the objective lens used for pickup. Aperture) can be achieved by increasing the oral rate. Recently, red semiconductor laser light having wavelengths of 680 nm, 650 nm and 635 nm and, furthermore, 400 nm to 500 nm of blue violet semiconductor laser light (hereinafter referred to as "blue violet laser light"), which can be recorded at a very high density. The development is rapidly progressing to the level to be used, and the development of the optical recording medium for applying them is being performed. In particular, as blue violet lasers are commercialized, development of optical recording systems using blue violet lasers and high NA pickups has been made, and a rewritable optical recording medium having a recording layer and an optical recording system capable of causing a phase change is a DVR system. Known (see, for example, Hikari Memory Kokusai Shinpozium (ISOM2000) Yokoshu, pp. 210-211). Certainly successful results have been obtained with respect to the problem of recording information on a rewritable optical recording medium having a high density.

In the above-described optical recording medium for an optical recording system, when utilizing a blue violet laser and a high NA pickup, reducing the distance from the laser light incident surface of the recording medium to the recording layer (i.e., reducing the thickness of the light transmitting layer) Is preferred. Therefore, the thickness of the light transmitting layer is specified to be 100 m. Since such an optical recording medium uses a high NA pickup, the distance between the pickup and the light transmitting layer is narrow so that the pickup may contact the light transmitting layer due to the variation of the surface of the optical recording medium, which causes defects on the light transmitting layer. It has included problems that cause forming.

In order to solve this problem, in order to prevent the formation of defects on the light transmitting layer, it has already been proposed to provide a defect preventing layer or a hard coating layer on the light transmitting layer using a spin coating method or a vacuum deposition method (eg See, for example, Japanese Patent No. 11 2,467 or Japanese Laid-Open Patent Publication No. 2000-67468). However, an anti-corrosion layer or a hard coating layer is provided one by one on the light transmitting layer according to the above-mentioned method, thus including the problem of low productivity. In addition, in the case of providing the defect preventing layer or the hard coating layer, the thickness of the outer portion of the layer tends to be large due to the centrifugal force, resulting in insufficient accuracy in the thickness.

On the other hand, there is a method of constructing a light transmitting layer by using a transparent thin film such as a cellulose acylate film and adhering the film to a recording layer having adhesiveness or pressure-sensitive adhesiveness (for example, JP-A-A). 2002-170280 or Japanese Patent Laid-Open No. 2002-197723). The thickness of the light transmitting layer is generally about 100 μm including an adhesive layer or a pressure sensitive adhesive layer formed by curing the adhesive or the pressure sensitive adhesive, and is optimized according to the wavelength of the irradiated laser light and NA. The recording medium constructed by such a method has excellent productivity, but commercially available cellulose acylate membranes contain 15 to 20% by weight of phosphate-based and / or phosphate-based plasticizers and, depending on the result of evaporation or migration of the plasticizer, Due to the reduction, they undergo dimensional changes under conditions of high temperature and high humidity, causing problems of deterioration of adhesion and curling. Thus, the conventional recording medium includes the problem that the recording of the information becomes impossible or the recorded information becomes impossible to read.

Further, Japanese Patent Laid-Open No. 2003-157579 describes an optical recording medium using a film containing a cyclic polyolefin as a light transmitting layer, but this medium does not have sufficient scratch resistance.

Disclosure of the Invention

SUMMARY OF THE INVENTION An object of the present invention is to provide a recording medium capable of reproducing an information signal by optical means, which is excellent in storage stability, especially under conditions of high temperature and high humidity, without generating dimensional changes and curling of the light transmitting layer. Allows excellent recording and playback. It is another object of the present invention to provide a recording medium which effectively prevents the formation of defects on its light incidence surface and has excellent storage stability.

As a result of thorough research, the inventors have found that the above-mentioned problems can be solved by the following configuration.

(1) A recording medium capable of reproducing an information signal by optical means, comprising: a support; A recording layer capable of recording an information signal; And a light transmitting layer capable of transmitting light sequentially.

The light transmitting layer comprises a light transmitting film having a moisture absorption expansion coefficient of 8 ppm /% RH to 62 ppm /% RH; The light transmitting layer includes a surface having a pencil hardness of at least 2H.

(2) The recording medium described in (1), wherein the light transmitting layer includes a hard coating layer on the light transmitting film,

The hard coat layer includes a first curable resin having a molecule having two or more ethylenically unsaturated groups; And a cured film formed from a curable composition comprising a second curable resin having a ring-opening polymerizer.

(3) In the recording medium described in (2), the light transmitting film is a cyclic polyolefin film.

(4) In the recording medium described in (2), the light transmitting film is a polycarbonate film.

(5) A recording medium capable of reproducing information signals by optical means, comprising: a support; A recording layer capable of recording an information signal; And a light transmitting layer capable of transmitting light sequentially.

The light transmissive layer comprises a cellulose acylate membrane comprising at least one deterioration inhibitor selected from the group consisting of (A) peroxide-decomposing agents, (B) radical chain inhibitors, (C) metal-inactive agents, and (D) acid trapping agents. It includes a light transmitting film containing.

(6) A recording medium capable of reproducing information signals by optical means,

support fixture; A recording layer capable of recording an information signal; And a light transmitting layer capable of transmitting light sequentially.

The light transmissive layer comprises a light transmissive membrane comprising a cellulose acylate membrane having an organic chlorine-containing solvent of 10 ppm or less.

(7) A recording medium capable of reproducing an information signal by optical means,

support fixture; A recording layer capable of recording an information signal; And a light transmitting layer capable of transmitting light in this order,

The light transmissive layer comprises a light transmissive membrane comprising a cellulose acylate membrane comprising a polyhydric alcohol ester of an aliphatic polyhydric alcohol and a monocarboxylic acid.

(8) In the recording medium described in (7), the monocarboxylic acid has an aromatic ring or a cycloalkyl ring.

(9) In the recording medium described in (7) or (8), the aliphatic polyhydric alcohol is one of a dihydric to 20-valent alcohol.

(10) The recording medium described in any one of (5) to (9), wherein the light transmitting film has a moisture absorption expansion coefficient of 8 ppm /% RH to 62 ppm /% RH.

 (11) The recording medium described in any one of (5) to (10), wherein the light transmitting layer includes a hard coating layer on the light transmitting film; The hard coat layer includes a cured film formed from the curable composition, and the curable composition includes a curable resin that can be cured with active energy light.

(12) The recording medium described in (11), wherein the curable composition comprises: a first curable resin having a molecule having two or more ethylenically unsaturated groups; And a second curable resin having a ring-opening polymerizer.

(13) In the recording medium described in any one of (1) to (12), the light transmitting layer has a thickness of 50 µm to 300 µm.

The present invention can provide a recording medium having excellent storage stability even under high temperature and high humidity, without suffering from flatness deterioration, and having excellent recording and reproducing performance. In addition, the present invention can provide a recording medium which is prevented from defects or contaminants on the surface of the recording medium and which has excellent storage stability. The recording medium of the present invention is particularly effective for an optical recording system using a blue violet laser and high NA pickup.

Detailed description of the invention

The recording medium of the present invention will be described in more detail below. In addition, the term "(numerical value 1) to (numerical value 2)" in the present specification means "including from (number 1) to (number 2)".

The recording medium (information recording medium) of the present invention is a recording medium capable of reproducing an information signal by optical means. The recording medium of the present invention basically includes a support, a recording layer capable of recording an information signal, and a light transmitting layer formed on the recording layer and capable of transmitting light. The component layers may be interchanged or combined without departing from the scope of the invention. One or more layers are required to be present as each component layer, and each component layer may include a plurality of identical layers, or one component layer may include a plurality of layers different in composition or property. Specifically, providing two recording layers and two light transmission layers on one side of the support, such as support / recording layer / light transmitting layer / recording layer / light transmitting layer or light transmitting layer / recording layer / support / It is possible to provide one recording layer and one light transmitting layer at both ends of the support, such as a recording layer / light transmitting layer. In addition to the above-mentioned configuration, a known antistatic layer, a known lubricating layer, a known protective layer, and a known reflective layer can be provided. Also, the side opposite to the side of the support provided with the recording layer can be label printed.

The recording medium of the present invention can be held within a cartridge. The present medium is not limited as far as its size, and regarding the disc-shaped recording medium, the diameter thereof may be selected, for example, in the range of 30 to 300 mm, and 32, 51, 65, 80, 120 , 130, 220, or 300 mm.

In the recording medium of the present invention, the support to be described below is a base which functions to hold the recording layer and the light transmitting layer mechanically.

The material constituting the support may be any of synthetic resin, ceramic, and metal. Typical examples of the synthetic resins which are preferably used are various thermosetting resins or thermoplastics such as polycarbonate, polymethyl, methacrylate, polystyrene, polycarbonate / polystyrene polymer, polyvinyl chlorine, alicyclic polyolefin, and polymethylpentane Resins and various radiation curable resins (including UV light curable resins and visible light durable resins). These may also be synthetic resins containing mixed metal powders or ceramic powders. General examples of ceramics used include soda lime glass, soda aluminosilicate glass, borosilicate glass, and quartz glass. Examples of metals used include aluminum, copper, and iron.

Among these, polycarbonates and amorphous polyolefins are preferred in view of the stability of the dimensions and the price, and polycarbonate is most preferred.

The thickness of the support is preferably 0.3 to 3 mm, more preferably 0.6 to 2 mm, and most preferably within the range of 1.1 mm ± 0.3 mm.

Pregrooves for displaying or tracking information such as address signals are formed on the surface of the support. Such pregrooves are preferably formed directly on the support during injection molding or extrusion molding of a resin material such as polycarbonate.

In addition, the formation of the pregroove may be performed by providing a pregroove layer. As the material for the pregroove layer, a mixture of one or more monomers (or oligomers) selected from acrylic acid monoesters, diesters, triesters, tetraesters, pentaesters, and hexaesters of polyols and photopolymerization initiators can be used. The formation of the pregroove layer is, for example, by coating a solution of a mixture of the above-mentioned acrylate and polymerization initiator on a correctly formed mother mold (stamper), placing the support thereon, and then fixing the support and the coating layer. Obtained by irradiating the combination through a support or mother mold to harden the coating layer and then removing the support from the mother mold. The thickness of the pregroove layer is generally within the range of 0.01 to 100 μm, preferably 0.05 to 50 μm.

In the present invention, the track pitch of the pregroove on the support is preferably in the range of 200 to 400 nm, more preferably 250 to 350 nm.

In addition, the depth of the pregroove is preferably in the range of 10 to 150 nm, more preferably 20 to 100 nm, even more preferably 30 to 80 nm. The half width of the pregroove depth is preferably in the range from 50 to 250 nm, even more preferably from 100 to 200 nm.

When providing the light reflection layer to be described below on the recording medium of the present invention, it is preferable to form an undercoat layer on the side of the support provided with the light reflection layer for the purpose of flatness and adhesion improvement.

Examples of the material for the undercoat layer are polymethyl methacrylate, acrylic acid / methacrylic acid copolymer, styrene / maleic anhydride copolymer, polyvinyl alcohol, N-methylol acrylamide, styrene / vinyl toluene copolymer, chlorosulfo Polymeric materials such as nated polyethylene, nitrocellulose, polyvinyl chloride, chlorinated polyolefins, polyesters, polyimides, vinyl acetate / vinyl chloride copolymers, ethylene / vinyl acetate copolymers, polyethylene, polypropylene, and polycarbonates; And surface improvers such as silane binders.

The undercoating layer dissolves or diffuses the above-mentioned materials in a suitable solvent in order to prepare a coating solvent, and the coating solvent thus prepared is coated on the surface of the support according to the coating method such as spin coating method, dip coating method or extrusion coating method. It can be formed by coating. The thickness of the undercoat layer is preferably in the range of 0.005 to 20 µm, more preferably 0.01 to 10 µm.

The light reflection layer can be arbitrarily prepared between the support and the recording layer for the purpose of improving the reflectance in the reproduction of the information. The light reflection layer may be formed on the support by ion plating, sputtering, or vacuum deposition of a light reflection material having a high reflectance for laser light. The thickness of the light reflection layer is generally in the range of 10 to 300 nm, preferably 50 to 200 nm. In addition, the reflectance of the light reflection layer is preferably 70% or more.

Examples of light reflecting materials having high reflectance include Mg, Se, Y, Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Mn, Re, Fe, Co, Ni, Ru, Rh, Pd, Semimetals or metals such as Ir, Pt, Cu, Ag, Au, Zn, Cd, Al, Ga, In, Si, Ge, Te, Pb, Po, Sn, and Bi and stainless steel. These light reflection layer materials may be used alone or in combination of two or more thereof. They can also be used as alloys. Among these, Cr, Ni, Pt, Cu, Ag, Au, Al, and stainless steel are preferable. Au, Ag, Al, and their alloys are particularly preferred, Au, Ag, and their alloys are most preferred.

In the recording medium of the present invention, the recording layer has a function of recording or rewriting information by allowing recording of an information signal on the layer via optical or magnetic means, and providing optical reproducing means (for example, laser light). It is a layer that reproduces the information signal from the layer through. When the recording medium is a read-only type recording medium, a material having a high reflectance is used for the recording layer, and when the recording medium is a rewritable recording medium, the recording layer material is a dye recording material, phase change according to the recording or reproduction principle. Recording material, and optical magnetic recording material. The thickness of the recording layer is preferably 2 to 300 nm, particularly preferably 5 to 200 nm.

Examples of the light reflecting material used for the recording layer include gold and silver.

Specific examples of materials used for dye recording include cyanine dyes, phthalocyanine dyes, naphthalocyanine dyes, azo dyes, naphthoquinone dyes, fullgid dyes, polymethine dyes, and acridine dyes.

Examples of materials used for phase change recording are indium, antimonium, tellurium, selenium, germanium, bismuth, vanadium, gallium, platinum, gold, silver, copper, tin and arsenic (oxides, nitrides, carbides, sulfides, and Alloy containing fluoride). In particular, GeSbTe, AgInSbTe, and CuAlTeSb are preferred. It is also possible to use a laminated film of an indium alloy and tellurium alloy as the recording layer.

Examples of materials used for optical magnetic recording include terbium, cobalt, iron, gadolinium, chromium, neodymium, dysprosium, bismuth, platinum, samarium, holmium, praseodymium, manganese, titanium, palladium, erbium, ytterbium, lutetium, and tin ( Oxides, nitrides, carbides, sulfides, and alloys comprising fluorides. In particular, it is preferable that the recording layer is made of an alloy of a rare earth element and a transition metal, which is usually represented by TeFeCo, GdFeCo, or DyFeCo. The recording layer may also be formed using a layer film in which a cobalt film alternates with a platinum film.

In addition, incidental or highly reflective films (eg, aluminum, gold, or silver), such as silicon, tantalum, zinc, magnesium, calcium, aluminum, chromium, zirconium (alloys including oxides, nitrides, and carbides) It may be added in combination on this recording layer.

The recording layer using the recording material for dye recording preferably relates to recording and reproducing information of a dye having a maximum absorption in the wavelength region of the laser light used for recording using laser light having a wavelength of 500 nm or less. One, particularly preferably dyes having a maximum absorption at wavelengths of 500 nm or less. Examples of dyes used include cyanine dyes, oxonol dyes, metal complex dyes, azo dyes, and phthalocyanine dyes. Especially preferred examples thereof are Japanese Patent Application Laid-Open No. 4-74690, Japanese Patent Application Laid-Open No. 8-127174, Japanese Patent Application Laid-Open No. 11-53758, Japanese Patent Application Laid-open No. 11-334204, Japan Japanese Patent Laid-Open No. 11-334205, Japanese Patent Laid-Open No. 11-334206, Japanese Patent Laid-Open No. 11-334207, Japanese Patent Laid-Open No. 2000-43423, Japanese Patent Laid-Open No. 2000 -108513, and the dyes and triazole dyes, triazine dyes, cyanine dyes, merocyanine dyes, aminobutadiene dyes, phthalocyanine dyes, cinnamic acid dyes, and viologen dyes described in JP-A-2000-158818 , Azo dyes, oxonol dyes, benzoxazole dyes, and benzotriazole dyes. Among these, cyanine dyes, aminobutadiene dyes, benzotriazole dyes, and phthalocyanine dyes are preferable.

  In the case of using a recording material for dye recording, the recording layer dissolves the above-described dye and, if necessary, a binder in an appropriate binder to prepare a coating dissolving agent, and the resulting coating dissolving agent is prepared on a pregroove surface or light reflecting layer of the support. It can be formed by coating on the surface of to form a coating film, and drying the film. In addition, depending on the end use, various additives such as antioxidants, UV absorbers, plasticizers and lubricants may be added to the coating solvent as needed.

In addition, examples of methods for dissolving the dye or binder to be added include sonication, homogenizer treatment, dispersion treatment, sand mill treatment, and agitator treatment.

Examples of solvents for coating solubilizers include esters such as butyl acetate and cellulose acetate; Ketones such as methyl ethyl ketone, cyclohexane and methyl isobutyl ketone; Chlorinated hydrocarbons such as dichloromethane, 1,2-dichloroethane, and chloroform; Amides such as dimethylformamide; Hydrocarbons such as cyclohexane; Ethers such as tetrahydrofuran, ethyl ether, and dioxane; Alcohols such as ethanol, n-propanol, isopropanol, n-butanol, and diacetone alcohol; Fluorine-containing solvents such as 2,2,3,3-tetrafluoropropanol; And glycol ethers such as ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, and propylene glycol monoethyl ether. Such solvents may be used independently or in combination of two or more suitable combinations thereof in view of the solubility of the dyes or binders used.

Examples of binders include natural organic polymer materials such as gelatin, cellulose derivatives, dextran, rosin, and rubber; And polyurethanes, hydrocarbon-based resins (eg, polyethylene, polypropylene, polystyrene, and polyisobutylene), vinyl-based resins (eg, polyvinyl chlorine, polyvinylidene chlorine, and polyvinyl chlorine / polyvinyl Acetate, and polymethyl methacrylate), acrylic resins (polymethyl acrylate and polymethyl methacrylate), polyvinyl alcohol, polyethylene chloride, and initial condensates of thermosetting resins (eg, epoxy resins, butyral resins) , Rubber derivatives, and phenol / formaldehyde). When using a binder combined with a dye as the recording layer material, the amount of the binder used is preferably 0.01 to 5-fold (weight ratio), more preferably 0.1 to 5-fold, based on the dye. It is also possible to improve the storage stability of the recording layer by mixing the binder with the recording layer.

The concentration of the dye in the coating solvent thus prepared is generally in the range of 0.01 to 10% by weight, preferably 0.1 to 5% by weight.

Examples of coating methods include spray coating methods, spin coating methods, dip coating methods, roll coating methods, blade coating methods, doctor roll coating methods and screen printing methods. The coating temperature may be 23 to 50 ° C without particular problem, preferably 24 to 40 ° C, more preferably 25 to 37 ° C.

Various anti-fading agents may be mixed in the recording layer to improve the light speed of the recording layer.

As anti-fading agents, singlet oxygen quenchers are generally used. As the singlet oxygen quencher, those known and described in published documents such as patent specifications may be used. Specific examples thereof include Japanese Patent Application Laid-Open No. 58-175693, Japanese Patent Application Laid-Open No. 59-81194, Japanese Patent Application Laid-Open No. 60-18387, Japanese Patent Application Laid-Open No. 60-19586, and Japan Japanese Patent Laid-Open No. 60-19587, Japanese Patent Laid-Open No. 60-35054, Japanese Patent Laid-Open No. 60-36190, Japanese Patent Laid-Open No. 60-36191, Japanese Patent Laid-Open No. 60- 44554, Japanese Patent Laid-Open No. 60-44389, Japanese Patent Laid-Open No. 60-44390, Japanese Patent Laid-Open No. 60-54892, Japanese Patent Laid-Open No. 60-47069, Japanese Laid Open Patent Publication No. 63-209995, Japanese Patent Application Laid-Open No. 4-25492, Japanese Patent Application Publication No. 1-38680, and Japanese Patent Application Publication No. 6-26028, German Patent No. 350399, and Nihon Ka Kakukai-shi, 1992, No. Includes those described on page 10, 1141.

The composition of the anti-fading agent such as the singlet oxygen quencher is generally in the range of 0.1 to 50% by weight, preferably 0.5 to 45% by weight, more preferably 3 to 40% by weight, particularly 5 to 25% by weight. desirable.

The intermediate layer (barrier layer) may be formed on the surface of the recording layer for the purpose of improving the adhesiveness to the light transmitting layer and the storage property of the dye. The barrier layer is a layer comprising a material, such as an oxide, nitride, carbide, or sulfide, containing one or more Zn, Si, Ti, Te, Sm, Mo, and Ge atoms and may be mixed such as ZnS-SiO ₂ . The baler layer may be formed by sputtering, vacuum deposition ion plating, or the like, and the thickness thereof is preferably adjusted to 1 to 100 nm.

In the video recording medium of the present invention, the light transmitting layer serves to guide physically concentrated reproduction light to the recording layer, and at the same time, to protect the recording layer chemically and physically. The light transmitting layer of the present invention is preferably constituted by a film having a thickness thinner than that of the support.

Also, in the present invention, the term "light transmission" is substantially transparent (in transmittance, at least 70%, preferably to light of a wavelength (eg 600 to 800 nm) used for optical means for use in reproduction recording. Make it more than 80%).

The light transmitting layer of the present invention comprises a light transmitting film having a hygroscopic expansion coefficient of 8 ppm /% RH to 62 ppm /% RH. If the hygroscopic expansion coefficient is out of the above-mentioned range, the recording medium can be deformed in accordance with changes in the surroundings. This is due to the large difference in the hygroscopic expansion coefficient between the light transmitting film and the substrate. When the recording medium is deformed, the recording layer is adversely affected so that its adaptability for reproduction recording is degraded, and the stability of reproduction recording is deteriorated. The hygroscopic expansion coefficient is more preferably 8 ppm /% RH to 50 ppm /% RH, and even more preferably 8 ppm /% RH to 40 ppm /% RH.

In the present invention, the term " hygroscopic expansion coefficient " means a dimensional change of the membrane when it is changed to an environment of 25 ° C and 80% RH under an environment of 25 ° C and 20% RH. That is, the hygroscopic expansion coefficient in ppm /% RH is [[(L ₈₀ -L ₂₀ ) / L ₂₀ ] / (80-20)] × 10 ⁶ where L ₂₀ is at 25 ° C. and 20% RH Membrane size, L ₈₀ denotes the membrane size at 25 ° C. and 80% RH). For example, the hygroscopic expansion coefficient of a membrane can be determined by cutting it into rectangles 5 cm wide and 28 cm long and measuring its length in an environment of 25 ° C. and 20% RH and in an environment of 25 ° C. and 80% RH. .

The hygroscopic expansion coefficient of the light transmitting membrane can be adjusted by appropriately selecting the kind and amount of the material and the additive of the membrane. Specifically, as the light transmitting membrane, a cellulose acylate membrane containing a specific deterioration agent, a cellulose acylate membrane containing a reduced amount of chlorine-containing organic solvent, a cellulose acylate membrane including a specific polyhydric alcohol ester, or Preference is given to using polycarbonate membranes.

As the light transmitting film used for the light transmitting layer of the present invention, those produced without stretching are preferable. When produced by applying the stretching technique, the film can exhibit optical anisotropy in the stretching direction. Such a film is not preferable as the light transmitting layer of the recording medium of the present invention. In addition, stretching may cause anisotropy of thermal expansion, which is not preferable in view of long term storage stability.

The light transmitting membrane used for the light transmitting layer of the present invention is preferably a film containing a cellulose derivative (particularly cellulose acylate), a cyclic polyolefin, or a polycarbonate.

Cellulose has a basic molecular structure of six rings, and has three hydroxyl groups (OH) in this basic unit. Cellulose acylates can be synthesized by esterifying hydroxyl groups using glacial acetic acid, propionic acid, butyric acid, acetic anhydride, or propionic acid anhydride. Part or all of the three hydroxyl groups can be esterified depending on the synthetic conditions. The cellulose acylates in which two or more hydroxyl groups are esterified in the ester can be formed into thin sheets by a casting method or a melt extrusion method, and the synthesized cellulose acetate is a permeable material having a refractive index of approximately 1.5, and a small inherent It has birefringence and has little dependence on light incident angle. The cellulose acylate film obtained by applying tension to the cellulose acylate is a rough film and maintains the internal birefringence of the material in which the difference between the birefringence in the longitudinal direction and the birefringence in the transverse direction is reduced. Therefore, the membrane is suitable as the light transmitting membrane of the present invention.

The cellulose acylate is preferably adjusted to be substantially transparent (70% or more, preferably 80% or more in transmittance) for light having λ of 350 to 450 nm by selecting conditions for synthesizing cellulose derivatives. In addition, since the cellulose acylate may be yellow or white depending on the conditions for synthesizing the cellulose derivative, the recording medium constituted by using such a yellow or white material may be used for the reproduction of the signal reproduced due to the decrease in reflectance. It may cause deterioration of the output.

Cellulose acylates have a low tear strength and low folding endurance, and in particular have the drawback that they are severely broken under low humidity conditions and susceptible to rupture. Adding low molecular plasticizers has been conventionally performed for the purpose of giving flexibility. Examples of such plasticizers include phosphate plasticizers such as triphenyl phosphate, tricresyl phosphate, triethyl phosphate, and diphenylbiphenyl phosphate, phthalate plasticizers such as dimethyl phthalate, diethyl phthalate, and dimethoxyethyl phthalate, ethyl phthalate Glycolate plasticizers such as tharyl ethyl glycol. As other plasticizers, toluenesulfonamide-based plasticizers and triacetin (glycerine triacetate) are used.

However, the above mentioned plasticizers are low molecular weight materials and have a boiling point not exceeding 300 ° C. at most. On the other hand, cellulose acylate is known as a polymer having low compatibility with other materials, and a plasticizer having a slight compatibility has a significant drawback that it has only a low boiling point as mentioned above. Therefore, severe migration of the plasticizer occurs as the membrane is formed, resulting in an inhomogeneous distribution of the plasticizer in the depth direction of the membrane. It is known that heterogeneity can cause curling of the membrane or that subsequent processing of the membrane involves problems because plasticizers leak onto the surface of the membrane. Therefore, in order to eliminate the drawbacks, for example, attempts have been made to mix polymeric plasticizers such as cellulose acylates with polyester ethers, polyester-urethanes or polyesters, or combinations of polymeric plasticizers and low molecular plasticizers, for example , Japanese Patent Laid-Open No. 47-760, Japanese Patent Laid-Open No. 43-16305, Japanese Patent Laid-Open No. 44-32672, and Japanese Patent Laid-Open No. 2-292342), the intended purpose This has been almost achieved. However, the use of such supports, when compared to supports containing only low molecular weight plasticizers (e.g. triphenyl phosphate), represents a severely deteriorated safety when stored for long periods of time and may cause coloring and breakage of the molecular rings. It has been found to have possible drawbacks.

In the present invention, in order to obtain long-term storage stability, the cellulose acylate membrane

(A) peroxide decomposers;

(B) radical chain inhibitors:

(C) metal deactivator: and

(D) It is preferable to mix at least one deterioration inhibitor of the acid trapping agent.

Or in order to obtain long term storage stability, the composition of the organic chlorine-containing solvent contained in cellulose acetate is adjusted to a low step of 10 ppm or less, or the polyhydric alcohol ester of aliphatic polyhydric alcohol and one or more mono to the cellulose acylate membrane It is also preferred to mix carboxylic acids.

The deterioration inhibitor used in the present invention is described below. In the present invention, the compounds represented by the following structural formulas (A-I), (A-II), and (A-III) are preferred as peroxide decomposers (A); The compound represented by the following structural formula (B-I) is preferred as a radical chain inhibitor (B); The compound represented by the following structural formulas (C-I), (C-II), and (C-III) is preferably a metal inactive agent (C); Structural Formulas (D-I), (D-II), (D-III), (D-IV), (D-V), (D-VI), (D-VII), and (D-VII) The compound represented by the formula (I) is preferably an acid trapping agent (D).

In the structural formulas (A-I) to (D-VIII), X represents a hydrogen atom, an alkali metal or an alkaline earth metal. R ₁₀ represents an alkyl group, an alkenyl group, or an aryl group. Each of R ₂₀ , R ₂₁ , and R ₂₂ , which may be the same or different, represents an alkyl group, an alkenyl group, an aryl group, an alkoxy group, an alkenoxy group, an aryloxy group, an alkylthio group, an alkenylthio group, or an arylthio group. Each of R ₃₀ and R ₃₁ , which may be the same or different, represents an alkyl group, an alkenyl group, or an aryl group. R ₄₀ represents an alkyl group. R ₄₁ , R ₄₂ and Y, which may be the same or different, each represent a hydrogen atom, an alkyl group, an alkenyl group, an aryl group, a heterocyclic group, an alkoxy group, an alkenoxy group, an aryloxy group, a heterocyclic oxy group, an alkylthio group, Alkenylthio group, arylthio group, hydroxyl group, an amino group which may have a substituent, carbamoyl group, sulfamoyl group, alkoxycarbonyl group, arylsiloxane group carbonyl group, halogen atom, nitro group, cyano group, acyl group, or acyloxy group Indicates. m represents the integer of 0-2. R ₆₉ and R ₆₁ , which may be the same or different, each represent an alkyl group, an alkenyl group, an aryl group, or a heterocyclic group. Z represents a group defined for Y and n represents an integer from 0 to 4. When m represents 2, plural Y's may be the same or different from each other, and when n represents an integer of 2 to 4, plural Z's may be the same or different from each other. R ₂₀ and R ₂₁ or R ₃₀ and R ₃₁ may be bonded to each other to form a 5-ring to 7-ring.

In addition, each of R ₁ , R ₂ , and R ₃ , which may be the same or different, represents a hydrogen atom, an aliphatic group, an aromatic group, a heterocyclic group, or an amino group. Two or more of R ₁ , R ₂ , and R ₃ may be bonded to each other to form a 5-ring to 8-ring. R ₁ And R ₂ may cooperate to form an unsaturated group. If R ₁ , R ₂ , and R ₃ do not simultaneously represent a hydrogen atom, an unsaturated group may be linked to R ₃ to form a 5-ring to 8-ring. . M ₁ represents an alkali metal or an alkaline earth metal, q represents ₁ when M ₁ represents an alkali metal, or 2 when M ₁ represents an alkaline earth metal. Each of R ₈₁ and R ₈₂ , which may be the same or different, represents an alkyl group, an alkenyl group, an aryl group, or a heterocyclic group. M ₂ represents an alkali metal, M ₃ represents an alkali metal or an alkaline earth metal, u is M ₃ 2 represents an alkali metal, or M ₃ 1 is shown when this alkaline earth metal is shown. R ₉₁ , R ₉₂ , R ₉₃ , and R ₉₄ , which may be the same or different, each represent a hydrogen atom, an alkyl group, an alkenyl group, an aryl group, or a heterocyclic group. Two or more of R ₉₁ , R ₉₂ , R ₉₃ , and R ₉₄ may be bonded to each other to form a 5-ring to 8-ring.

The compound represented by (D-VII) in the structural formula (A-I) is explained in more detail below. X represents a hydrogen atom, an alkali metal (eg lithium, sodium, or potassium) or an alkaline earth metal (eg calcium, barium, or magnesium). R ₁₀ , R ₂₀ , R ₂₁ , R ₂₂ , R ₃₀ , R ₃₁ , R ₄₀ , R ₄₁ , R ₄₂ , Y, R ₈₁ , R ₈₂ , R ₉₁ , R ₉₂ , R ₉₃ , R ₉₄ , R ₆₀ , And in the definition of R ₆₁ an alkyl group is a straight, branched, or cyclic alkyl group (eg, methyl, ethyl, propyl, isopropyl, tertbutyl, cyclohexyl, terthexyl, teroctyl, dodecyl, hexadecyl, octadecyl Or benzyl) and R ₁₀ , R ₂₀ , R ₂₁ , R ₂₂ , R ₃₀ , R ₃₁ , R ₄₀ , R ₄₁ , R ₄₂ , Y, R ₈₁ , R ₈₂ , R ₉₁ , R ₉₂ , R ₉₃ Alkenyl groups in the definition of R ₉₄ , R ₆₀ , and R ₆₁ are straight, branched, or cyclic alkenyl groups (eg, vinyl, allyl, 2-pentenyl, cyclohexenyl, hexenyl, dodecenyl, or Octadecenyl) and R ₁₀ , R ₂₀ , R ₂₁ , R ₂₂ , R ₃₀ , R ₃₁ , R ₄₀ , R ₄₁ , R ₄₂ , Y, R ₈₁ , R ₈₂ , R ₉₁ , R ₉₂ , R ₉₃ , In the definition of R ₉₄ , R ₆₀ , and R ₆₁ , an aryl group is a single benzene ring or an aryl group of a polycondensed ring (eg, phenyl, Naphthyl, or anthranyl), and R ₁₀ , R ₂₀ , R ₂₁ , R ₂₂ , R ₃₀ , R ₃₁ , R ₄₀ , R ₄₁ , R ₄₂ , Y, R ₈₁ , R ₈₂ , R ₉₁ , R ₉₂ , In the definition of R ₉₃ , R ₉₄ , R ₆₀ , and R ₆₁ , a heterocyclic group is a 5- to 7-ring (eg, containing at least one of a nitrogen atom, a sulfur atom, and an oxygen atom as a ring structure atom; Peryl, pyrrolyl, imidazolyl, pyridyl, purinyl, chromanyl, pyrrolidyl, or morpholinyl).

R ₁₀ represents an alkyl group, an alkenyl group, or an allyl group. R ₂₀ , R ₂₁ , and R ₂₂ , which may be the same or different, are each an alkyl group, an alkenyl group, an aryl group, an alkoxy group (eg, methoxy, ethoxy, methoxyethoxy, octyloxy, benzyloxy, cyclo Hexyloxy, isopropoxy, tetradecyloxy, or octadecyloxy), alkenoxy groups (eg, vinyloxy, propenyloxy, cyclohexenyloxy, dodecenyloxy, or octadecenyloxy) , Aryloxy groups (e.g., phenoxy or naphthoxy), alkylthio groups (e.g., methylthio, ethylthio, isopropylthio, cyclohexylthio, benzylthio, octylthio, dodecylthio, hexadecyl Thio, or octadecylthio), alkenylthio groups (eg, vinylthio, allylthio, cyclohexenylthio, or hexadecenylthio), or arylthio groups (eg, phenylthio or naphthylthio) ). R ₃₀ and R ₃₁ , which may be the same or different, represent an alkyl group, an alkenyl group, or an aryl group, respectively. R ₄₀ represents an alkyl group. R ₄₁ , R ₄₂ , and Y, which may be the same or different, each represent a hydrogen atom, an alkyl group, an alkenyl group, an aryl group, a heterocyclic group, alkoxy, alkenoxy, allyloxy, alkylthio, alkenyl as in R ₂₀ Thio, or arylthio groups, heterocyclic oxy groups (eg, imidazolidinyloxy, morpholinyloxy, tetrahydropyran-3-yloxy, or 1,3,5-triazine-2-yloxy ), Hydroxyl groups, optionally substituted amino groups (eg, amino, alkylamino, arylamino, dialkylamino, acylamino, sulfoneamino, ureido, or urethane), carbamoyl groups (eg, N -Methylcarbamoyl, N-phenylcarbamoyl, or N, N-dienylcarbamoyl), sulfamoyl groups (e.g., N-ethylsulfamoyl or N-phenylsulfamoyl), alkoxycarbonyl groups (e.g., For example, methoxycarbonyl group, butoxycarbonyl group, cyclohexyloxycarbonyl, octyloxycarbon , Hexyloxycarbonyl, or octadecyloxycarbonyl), aryloxycarbonyl group (eg, phenyloxycarbonyl or naphthyloxycarbonyl), halogen atom (eg, fluorine atom, chlorine atom, or Bromine atom), nitro group, cyano group, acyl group (for example, acetyl, benzoyl, or naphthoyl) or acyloxy group (for example, acetyloxy, benzoyloxy, or naphthoyloxy). m represents an integer of 0 to 2. R ₆₀ and R ₆₁ , which may be the same or different, each represent an alkyl group, an alkenyl group, an aryl group or a heterocyclic group. Z represents the same group defined for Y and n represents an integer from 0 to 4. When m represents 2, plural Y's may be the same or different from each other, and when n represents an integer of 2 to 4, plural Z's may be the same or different from each other. R ₂₀ and R ₂₁ or R ₃₀ and R ₃₁ may be bonded to each other to form a 5-ring to a 7-ring.

R ₁ , R ₂ , and R ₃ , which may be the same or different Each represents a hydrogen atom, an aliphatic group, an aromatic group, a heterocyclic group, or an amino group. Two or more of R ₁ , R ₂ , and R ₃ may be bonded to each other to form a 5-ring to 8-ring. In addition, R ₁ and R ₂ may cooperate to form an unsaturated group. If R ₁ , R ₂ , and R ₃ do not simultaneously represent a hydrogen atom, they may be linked to R ₃ to form a 5- to 8-ring. have. Aliphatic groups used herein are straight, branched, or cyclic alkyl groups (eg, methyl, ethyl, propyl, isopropyl, tertbutyl. Cyclohexyl, terthexyl, teroctyl, dodecyl, hexadecyl, octadecyl, or Benzyl), alkenyl groups (e.g. vinyl, allyl, 2-pentenyl, cyclohexenyl, hexenyl, dodecenyl, or octadecenyl), or alkynyl groups (e.g. propynyl or hexadecynyl) Wherein such group is optionally substituted. Aromatic groups as used herein refer to aryl groups (eg phenyl, naphthyl, or anthranyl) of a single benzene ring or condensed polycyclic ring. Such rings may have substituents. Heterocyclic groups as used herein include 5- to 7-rings (eg, peryl, pyrrolyl, imidazolyl, pyridyl, furinyl, containing one or more of nitrogen, sulfur, and oxygen atoms as ring constituent atoms) , Chromatinyl, pyrrolidyl, or morpholinyl). The amino group as used herein represents an amino group or an N-substituted amino group.

Examples of substituents of the above-mentioned groups may optionally include aliphatic groups, aromatic groups, heterocyclic groups, acyl groups, sulfonyl groups, sulfamoyl groups, and carbamoyl groups.

Two or more of R ₁ , R ₂ , and R ₃ are bonded to each other to form a 5- to 8-ring (eg, a pyrrolidine ring, an imidazole ring, an imidazoline ring, a pyrazolidine ring, a piperazine ring, Piperidine ring, morpholine ring, indolin ring, or quinoclidine ring). R ₁ and R ₂ may cooperate to form an unsaturated group, where the unsaturated group is bonded to R ₃ to form a 5- to 10-ring (eg, a pyridine ring, quinoline ring, putridine ring, or phenanthroline ring) May be formed.

M ₁ represents an alkali metal (eg lithium, sodium, or potassium) or alkaline earth metal (eg calcium, barium, or magnesium). R ₈₁ and R ₈₂ , which may be the same or different, represent an alkyl group, an alkenyl group, an aryl group, or a heterocyclic group, respectively. The alkyl group used here is a straight, branched, or cyclic alkyl group (e.g. methyl, ethyl, propyl, isopropyl, tertbutyl, cyclohexyl, terthexyl, teroctyl, dodecyl, hexadecyl, octadecyl, or benzyl Alkenyl group represents a straight, branched, or cyclic alkenyl group (e.g., vinyl, allyl, 2-pentenyl, cyclohexenyl, hexenyl, dodecenyl, or octadecenyl) The group represents an aryl group (eg phenyl, naphthyl, or anthranyl) of a single benzene ring or condensed polycyclic ring. Heterocycles as used herein are 5- to 7-rings (eg, peryl, pyrrolyl, imidazolyl, pyridyl, furinyl, containing one or more nitrogen atoms, sulfur atoms, and oxygen atoms as ring constituent atoms) , Chromatinyl, pyrrolidyl, or morpholinyl). M ₂ represents an alkali metal (eg lithium, sodium, or potassium). M ₃ represents an alkali metal (eg lithium, sodium, or potassium) or alkaline earth metal (eg calcium, barium, or magnesium).

R ₉₁ , R ₉₂ , R ₉₃ , and R ₉₄ , which may be the same or different, represent an alkyl group, an alkenyl group, an aryl group, or a heterocyclic group, respectively. The alkyl group used here is a straight, branched, or cyclic alkyl group (e.g. methyl, ethyl, propyl, isopropyl, tertbutyl, cyclohexyl, terthexyl, teroctyl, dodecyl, hexadecyl, octadecyl, or benzyl ), Alkenyl groups represent straight, branched, or cyclic alkenyl groups (e.g., vinyl, allyl, 2-pentenyl, cyclohexenyl, hexenyl, dodecenyl, or octadecenyl) Aryl groups (eg, phenyl, naphthyl, or anthranyl) of a single benzene ring or condensed polycyclic ring. Heterocycles as used herein are 5- to 7-rings (eg, peryl, pyrrolyl, imidazolyl, pyridyl, furinyl, containing one or more nitrogen atoms, sulfur atoms, and oxygen atoms as ring constituent atoms) , Chromatinyl, pyrrolidyl, or morpholinyl).

R ₉₁ and R ₉₂ or R ₉₃ and R ₉₄ are bonded to each other to form a 5- to 8-ring (e.g., pyrrolidine ring, imidazoline ring, imidazolidine ring, pyrazolidine ring, pipepe Azine ring, piperidine ring, morpholine ring, indolidine ring, or quinoclidine ring).

Among the compounds represented by the structural formula (A-II), it is preferable that all of R ₂₀ to R ₂₂ are selected from an alkyl group, an aryl group, an alkoxy group, and an aryloxy group. R ₂₂ in all R ₂₀ is more preferably selected from an alkyl group, an aryl group, and an alkoxy group. Among the compounds having an aryloxy group, the benzene ring of the aryloxy group preferably has a substituent on its o-position. Among the compounds in which two or more or R ₂₂ in R ₂₀ are an aryloxy group, it is preferred that the o-position of one benzene ring is linked directly to the o-position of the other benzene ring or through a substituent on the o-position.

Among the compounds represented by the structural formula (B-I), those represented by the following structural formulas (B-I-I) and (B-I-II) are preferable.

In the formula, R _{40 ′} represents a tertiary alkyl group, R _{40 ″} and R _{40 ′ ′} , which may be the same or different, represent an alkyl group, and L represents a single bond or the following bonding group.

In a bonding group, R ₄₃ represents a hydrogen atom, an alkyl group, or an aryl group. R ₄₄ and R ₄₅ , which may be the same or different, each represent a hydrogen atom, an alkyl group, or an aryl group. In the above formula, R ₄₁ , R ₄₂ , Y and m are the same as defined for the formula (B-I), and Y 'is the same as defined for the Y. m 'and m "are the same as defined for m.

Among the compounds represented by the structural formula (D-I), those having 4 or more pKa are preferable, those having 4 to 9 pKa are more preferable, and those having 5 to 8 pKa are even more preferable. Most preferred are compounds having a pKa of 5 to 7. pKa is the dissolution constant of the conjugate acid of the amine compound and is the value determined in a mixed solvent of EtOH / H ₂ O = 4/1 at room temperature. Typically this value is obtained by the teatrimetric method. The amine compound is also preferably an oleophilic compound comprising at least 8 carbon atoms in total, more preferably at least 15 carbon atoms.

The amine compound is preferably a tertiary amine. Among the compounds represented by Structural Formula (D-I), most preferred are oleophilic compounds represented by Structural Formula (D-I-I) and having 4 or more pKa.

In the structural formula (D-I-I), R ₁ and R ₂ are the same as defined for (D-I). R _b1 to R _b5 , which may be the same or different, are each a hydrogen atom, an aliphatic group, an aromatic group, a heterocyclic group, an aliphatic oxy group, an aromatic oxy group, a heterocyclic oxy group, an aliphatic thio group, an aromatic thio group, a heterocyclic tee A group, a hydroxyl group, a halogen atom, a cyano group, a nitro group, an amino group which may have a substituent, a sulfonyl group, an acyl group, an acyloxy group, a sulfamoyl group, a carbamoyl group, or an ester group is shown. R ₁ and R ₂ , R ₁ And R _b5 , R ₂ and R _b1 or R _b1 on o-one of each other represent 2 of R _B5 and may combine with each other to form a 5-ring to 8-ring.

As the preferred acid trapping agent (D) of the present invention, further, an amine compound represented by the structural formula (D-VII) other than the compound described above will be described.

In the formula (D-VII), X represents a single bond or a 2- to 3-valent organic residue, and B ₁ represents an aryl group, provided that X ₁ does not represent -O- and-(CH ₂ ) _4- The amino group which has the allyloxy group or the nitrogen containing heterocyclic group is shown. p represents 2 or 3. Examples of X ₁ are a single bond, a carbon atom, a nitrogen atom or a phosphorus atom and -S-, -SO _2- , -O-Ar-O-, -O-Ar- (CR ₄ R ₅ ) _n -Ar-O -, 2- and trivalent residues which bind to B ₁ via a divalent linking group such as -O-Ar-SO ₂ -Ar-O-, -O-CH ₂ -Y ₁ -CH ₂ -O- Include. Here, Ar represents an aryl group, R ₄ and R ₅ each represents an alkyl group, and Y ₁ represents CR ₄ R ₅ or —CH ₂ OCH ₂ —. B ₁ is an amino group with nitrogen containing an aryl group, an aryloxy group, or a heterocyclic group having 4 or more pKa (value measured in a mixed solvent of ethanol / water = 4/1). The amino group may not be substituted or may have a substituent. Examples of substituents include alkyl groups, cycloalkyl groups, aralkyl groups, aryl groups, and heterocyclic groups. As amino groups, tertiary amino groups are particularly preferable, and cyclic tertiary amino groups are preferably used. Examples of the nitrogen-containing heterocyclic group include a pyrrolidino group, a piperidino group, a morpholino group, a piperazino group, a pyridyl group, a pyrimidyl group, a quinolyl group, an imidazolyl group, a pyrrolyl group, an indolino group, and tetrahydro A quinolyl group, an imidazolinyl group, a thiazolinyl group, an imidazolidinyl group, and a thiazolidinyl group. In addition, the amino group nitrogen-containing heterocyclic group may have another substituent.

Among the amine compounds of the present invention represented by Structural Formula (D-VIII), compounds having a molecular weight of 300 or more and having substantially no evaporation property are more preferable.

Among the amine compounds of the present invention represented by the structural formula (D-VII), compounds having essentially no evaporation properties and having a molecular weight of 200 or less per basic group are most preferred.

Among the compounds represented by the structural formula (B-I), compounds having a pKa of 4 to 9 are more preferable, compounds having a pKa of 5 to 8 are even more preferable, and compounds having a pKa of 5 to 7 are most preferred. desirable.

Specific examples of the compound of the present invention represented by structural formulas (A-I) to (D-X) include the compound described in [0064] of JP-A-5-197073.

Most of these compounds are commercially available and readily available. Other preferred examples of the amine compound represented by the structural formulas (D-I) and (D-VII) and the synthesis process thereof are described in US Patent Nos. 4,483,918, 4,555,479, 4,585,728, 4,639,415, and European US Examination Patent No. 264,730, Japanese Patent Laid-Open No. 58-102231, Japanese Patent Laid-Open No. 59-229557, Japanese Patent Laid-Open No. 61-73152, Japanese Patent Laid-Open No. 63-98662 , Japanese Laid-Open Patent Publication No. 63-115167, and Japanese Laid-Open Patent Publication No. 63-267944.

Next, the cellulose acylate film containing the organic chlorine-containing solvent is as low as 10 ppm or less.

In the membrane, in order to reduce the composition of the organic chlorine-containing solvent (mainly methylene chlorine) immediately after production, it has a core layer comprising cellulose acylate having a degree of substitution of 2.7 or less, and has a thickness of 0.5 μm to 15 μm, 2 It is preferred to form a cellulose acylate layer film having a surface layer on at least one side of the core layer, including cellulose acylate having a degree of substitution of 8 or more. This cellulose acylate layer film has a thickness of 0.5 μm to 15 μm, using dope prepared from a solvent containing methylene chlorine or N-methyl-2-pyrrolidone at a concentration of 70%, and at least 2.8 having a degree of substitution It can be produced by a solubilizer to film the surface layer comprising cellulose acylate having a and a solubilizer to film a core layer containing cellulose acylate having a degree of substitution of 2.7 or less from a solvent containing acetone at a concentration of 60% or more. .

The cellulose acylate layer membrane of the present invention having a layered structure in which the surface layer has cellulose acylate having a degree of substitution of 2.8 or more, and the core layer has cellulose acylate of 2.7 or less at substitution degree, significantly reduces the composition of the solvent contained therein. It allows to provide a film having excellent resistance to moist heat. A membrane formed from cellulose acylate having a degree of substitution of 2.8 or more (hereinafter also referred to as "TAC" in this case of cellulose acetate) is a membrane formed from cellulose acylate having a substitution degree of 2.7 or less (hereinafter also referred to as "DAC" in this case of cellulose acetate). Has excellent water vapor permeability.

An example giving an example of cellulose acetate is given below. TAC (cellulose acylates having a degree of substitution of 2.8 or more), provided on the surface layer of DAC (cellulose acylates having a degree of substitution of 2.7 or less), can prevent the penetration of moisture from outside air, and thus only for moist heat DACs with insufficient resistance can be protected. As a result, the entire membrane has excellent resistance to moisture and heat.

As for the substitution degree of cellulose acylate or TAC whose substitution degree is 2.8 or more, 2.8-3.0 are preferable and 2.9-3.0 are more preferable. As for the substitution degree of the cellulose acylate or DAC whose substitution degree is 2.7 or less, 2.0-2.7 are preferable and 2.5-2.7 are more preferable.

Also, as used herein, "degree of substitution" refers to the proportion of hydroxyl groups esterified with fatty acids based on the hydroxyl groups of cellulose.

The degree of substitution can be determined according to ASTM-D817-96.

First, to determine the degree of acetylation, the dried cellulose acylate is measured and dissolved in a mixed solubilizer of acetone and dimethyl sulfoxide (volume 4: 1). Then, 1 mol / liter of the predetermined sodium hydroxide aqueous solubilizer is added to the solvent, followed by saponification at 25 ° C. for 2 hours. Phenolphthalein was added thereto as an indicator, and titrated with excess sodium hydroxide with 0.5 mol / liter of sulfuric acid. Control experiments were performed in the same manner as described above. The degree of acetylation (%) was calculated according to the following formula.

Acetylation degree (%) = (6.005 × (B-A) × F) / W

In the above formula, A represents the amount (ml) of 0.5 mol / liter sulfuric acid required to titrate the sample, B represents the amount (ml) of 0.5 mol / liter sulfuric acid, and F represents the coefficient of 0.5 mol / liter sulfuric acid. And W represents the weight of the sample. In addition, in the system containing plural kinds of acyl groups, the amount of each acyl group was determined using the difference in pKa. The degree of acetylation was also determined according to the method described in the document (T. Sei, K. Ishitani, R. Suzuki, K. Ikematsu; Polymer Journal 17, 1065, 1985). In addition, the predetermined degree of acetylation or other degree of acylation was converted to the degree of substitution in consideration of the molecular weight. In addition, the degree of acyl substitution of the 2-position, 3-position, and 6-position of cellulose acylate was determined by acylating acyl groups and cellulose acetate not previously used in acylation, followed by Tezuka et al., Carbohydr . Res. 273 (1995), 83-91 was added to 13C-NMR.

In the present invention, the cellulose acylate film having the above-described layer structure has a two-layered cellulose acetate film comprising a surface layer of the TAC and an adjacent layer of the DAC and a surface layer of the TAC provided on both ends thereof, the core of the DAC. A cellulose acetate membrane having a three layer structure comprising a layer. Also included are films comprising three or more layers. In the three-layer film of the present invention, the thicknesses of the two surface layers may not be the same, but from the viewpoint of balancing the mechanical properties of the film, the same is preferable. The two-layered cellulose acetate film of the present invention can achieve the purpose of preventing moisture by providing a functional film such as a polarized film or a photosensitive film on the surface of the DAC constituting the core layer. The problem of moisture-proof storage of a two-layered film can be solved by rolling and wrapping the film in a moisture-proof state. In the present invention, a layer film having three or more layers, with the TAC surface layer provided on both sides of the DAC core layer, is preferred. This structure prevents moisture from penetrating into the membrane under any storage conditions, and maintains good transparency, dimensional stability, and resistance to moist heat of the membrane for a long time.

In addition, since the surface layer with TAC is as thin as 0.5 to 15 [mu] m, the amount of organic solvent used can be significantly reduced, contributing to improving stability in the operating environment and the surrounding environment, and also haze caused by residual solvent. ) Can solve the problem. Here, the thickness of the layer having TAC is preferably 0.5 to 10 m, more preferably 1.0 to 5,0 m.

The above description with reference to cellulose acetate can be applied to other cellulose acylates.

When using an organic chlorine-containing solvent when forming a TAC film, the content of the organic chlorine-containing solvent contained in the membrane immediately after production is 10 ppm or less under conditions substantially the same as those for the conventional cellulose triacetate membrane. Can be reduced. The content of the organic chlorine-containing solvent is preferably 5 ppm or less. Therefore, stability can be more achieved in the operating environment and the surrounding environment, and the problem of haze caused by residual solvent can also be solved remarkably. In the present invention, even when the two surface layers of the three-layer structure are formed from cellulose acylate dissolved in methylene chloride, the content of the organic chlorine-containing solvent (mainly methylene chloride) contained in the membrane immediately after preparation is 10 ppm or less. Can be reduced.

Providing a cellulose acylate film containing an organic chlorine-containing solvent in an amount of 10 ppm or less is a conventional method of forming a film having a thickness of 50 μm or more from a dope containing methylene chloride, unless the severe drying operation is performed. It has been practically impossible because it fails to provide membranes of 10 ppm or less in the content of the containing solvent.

In addition, the boiling point of N-methyl-2-pyrrolidone (NMP) is higher than the boiling point of methylene chloride, resulting in a significant amount of residual solvent. However, in the present invention, since the thickness of the layer with TAC is thin (up to 15 μm), even when two layers are formed in a three-layer film, the amount of residual NMP immediately after production of the film may be reduced to 2000 ppm or less. Can be. The amount of residual NMP is preferably 1500 ppm or less. Therefore, the amount of drying for drying the surface layer is not large, and there is no problem in producing the film. In addition, since the amount of the residual solvent is small and the chlorine-containing solvent is not used for film formation, there is no problem of residual chlorine-containing solvent. In addition, haze that has been generated due to a large amount of residual NMP can be prevented, so that the transparency of the film can be maintained at an appropriate level during storage.

For cellulose acylate membranes prepared using chlorine-free solvents and their preparation, details are given in Hatsumei Kyokai Kokai Giho 2001-1745.

Next, cellulose acylates containing polyhydric alcohol esters of aliphatic polyhydric alcohols and one or more monocarboxylic acids are described below. Aliphatic polyhydric alcohol esters of the present invention are esters of aliphatic polyhydric alcohols having at least two hydroxyl groups and at least one monocarboxylic acid.

Aliphatic polyhydric alcohols used in the present invention are alcohols having two or more hydroxyl groups, represented by the following structural formula (a):

R _11- (OH) _n

In the formula (a), R ₁₁ represents an n-valent aliphatic organic group, n represents a positive integer of 2 or more, and the OH group represents an alcoholic and / or phenolic hydroxyl group.

Examples of n-valent organic groups include alkenyl groups (eg methylene, ethylene, trimethylene, or tetramethylene), alkenylene groups (eg ethenylene), alkynylene groups (eg ethylylene) , Cycloalkylene groups (eg, 1,4-dicyclohexanediyl), and alkanelliylyl groups (eg, 1,2,3-propaneriyl). n-valent aliphatic organic groups include those having substituents (eg, hydroxyl groups, alkyl groups, or halogen atoms). n is preferably 2 to 20, more preferably 2 to 5, particularly preferably 2 or 3.

Examples of preferred polyhydric alcohols are adonitol, arabitol, ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, 1,2-propanediol, 1,3-propanediol, dipropylene glycol, tripropylene Glycol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, dibutylene glycol, 1,2,4-butanetriol, 1,5-pentanediol, 1,6-hexanediol, hexane Triols, galactitol, mannitol, 3-methylpentane-1,3,5-triol, pinacol, sorbitol, trimethylolpropane, and xylitol. In particular, triethylene glycol, tetraethylene glycol, dipropylene glycol, tripropylene glycol, sorbitol, trimethylolpropane and xylitol are preferable.

As the monocarboxylic acid used in the polyhydric alcohol of the present invention, any known aliphatic monocarboxylic acid, alicyclic monocarboxylic acid, and aromatic monocarboxylic acid may be used, but are not particularly limited. The use of alicyclic monocarboxylic acids or aromatic monocarboxylic acids is preferred in view of the water vapor permeability of the final cellulose acylate membrane.

Examples of preferred monocarboxylic acids will be described below, but are not intended to limit the invention.

As the aliphatic monocarboxylic acid, fatty acids having straight or branched chains containing 1 to 32 carbon atoms may be preferably used. The number of carbons is preferably 1 to 20, particularly preferably 1 to 10. The presence of acetic acid is preferred because it increases the compatibility with the cellulose esters, and it is preferable to use a mixture of acetic acid and other monocarboxylic acids.

Examples of preferred aliphatic monocarboxylic acids include acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, enantiic acid, capric acid, pelargonic acid, capric acid, 2-ethyl-hexanecarboxylic acid, Undecylenic acid, lauric acid, tridecylic acid, mystic acid, pentadecylic acid, palmitic acid, heptadecylic acid, stearic acid, nonadecanoic acid, arachidic acid, behenic acid, lignoceric acid, sertic acid, heptacosano Saturated fatty acids such as icic acid, monticic acid, melisic acid, and racemic acid and unsaturated fatty acids such as undecylenic acid, oleic acid, sorbic acid, linoleic acid, linolenic acid, and arachidonic acid.

Preferred examples of alicyclic monocarboxylic acids include cyclopentanecarboxylic acid, cyclohexanecarboxylic acid, cyclooctanecarboxylic acid, and derivatives thereof.

Preferred examples of the aromatic monocarboxylic acid are benzoic acid such as toluic acid, aromatic monocarboxylic acid, wherein the benzoic acid, the alkyl group has two or more benzene rings such as biphenylcarboxylic acid, naphthalenecarboxylic acid, and tetralincarboxylic acid Benzoic acid is especially preferable including what went into this benzene ring, and its derivative (s).

The polyhydric alcohol esters used in the present invention are not particularly limited in terms of molecular weight. However, 300-1500 are preferable and 350-750 are more preferable.

Carboxylic acids in the polyhydric alcohol esters of the present invention may be used alone or in mixture of two or more thereof. In addition, all OH groups of the polyhydric alcohol may be esterified, or some of the OH groups may remain as OH groups. It is preferred to have three or more aromatic or cycloalkyl rings in the molecule for the esters.

Specific examples of the polyhydric alcohol esters used in the present invention are shown below, but do not limit the present invention.

The amount of polyhydric alcohol ester is preferably 3 to 30% by weight, more preferably 5 to 25% by weight, particularly preferably 5 to 20% by weight based on cellulose acylate.

Such polyhydric alcohol esters are preferably used in place of phosphates such as triphenyl phosphate conventionally used by mixing with cellulose acylate. That is, esters are preferably used for cellulose acylate membranes with or without phosphate in a reduced amount of 0.1 g / m ² .

As the polycarbonate membrane used in the present invention, the membrane described in JP-2003-157579 can be preferably used.

Next, the cyclic polyolefin membrane used in the present invention is described below.

As for the cyclic polyolefin membrane used in this invention, Unexamined-Japanese-Patent No. 5-65350, 6-107736, 6-248164, Japan Unexamined-Japanese-Patent No. 10 -60048, Japanese Patent Application Laid-Open No. 11-129399, Japanese Patent Application Laid-Open No. 11-216817, Japanese Patent Application Laid-Open No. 11-217446, Japanese Patent Application Laid-Open No. 11-217491, Japan Japanese Patent Laid-Open No. 2001-9859, Japanese Laid-Open Patent Publication No. 2001-163959, and Japanese Laid-Open Patent Publication No. 2002-249625.

The cyclic polyolefin used in the present invention has an alicyclic structure in the main chain and / or the side chain. From the viewpoint of mechanical strength and heat resistance, it is preferable to have an alicyclic structure in the main chain. Examples of the alicyclic structure of the polymer include a cycloalkane structure and a cycloalkene structure, and in view of mechanical strength and heat resistance, a cycloalkane structure and a cycloalkene structure are preferable. Among them, it is most preferable to have a cycloalkane structure, because it has excellent weather resistance and chemical resistance. The number of carbons constituting the alicyclic structure is not particularly limited, but is generally 4 to 30, preferably 5 to 20, more preferably 5 to 15, and an alicyclic structure having such a carbon atom number. This is because it exhibits balanced high mechanical strength, heat resistance, and formability.

The proportion of repeating units having an alicyclic structure in the cyclic polyolefin used in the present invention may be appropriately selected depending on its end use, but at least 30% by weight is general, at least 50% by weight, and 70% by weight. % Or more is more preferable. If the ratio of repeating units having an alicyclic structure in the cyclic polyolefin is too small, such a ratio is not preferable because a film having inferior heat resistance is brought about. The residual ratio of cyclic olefins which are not repeating units having an alicyclic structure in the cyclic olefin is not particularly limited and may be appropriately selected depending on the end use. As the cyclic polyolefin, thermoplastic olefins are preferred.

Specific examples of the polymer having an alicyclic structure include (1) norbornene-based polymers, (2) monocyclic olefin-based polymers, (3) cyclic conjugated diene-based polymers, and (4) vinyl-alicyclic hydrocarbon polymers. , And hydrogenated products thereof. Among them, norbornene-based polymers and hydrogenated products, cyclic conjugated diene-based polymers and hydrogenated products thereof are preferable, and norbornene-based polymers and hydrogenated products thereof are more preferable.

(1) norbornene-based polymer

The norbornene-based polymer is not particularly limited, but may be, for example, a norbornene-based monomer (norbornene by the procedure disclosed in Japanese Patent Application Laid-Open No. 3-14882 and Japanese Patent Laid-Open No. 3-122137). And those obtained by polymerizing a cyclic olefin monomer having a ring) may be used. Specific examples thereof include ring-opening polymerization products of norbornene-based monomers and hydrogenated products thereof, further polymers of norbornene-based monomers, and further polymerization products between norbornene-based and vinyl compounds.

Among these, hydrogenated products of ring-opening polymerization products of norbornene-based monomers, further polymers of norbornene-based monomers, and further polymerization products between norbornene-based monomers and copolymerizable vinyl compounds are preferred, and ring-opening polymerization of norbornene-based monomers is preferred. Particular preference is given to hydrogenated products of the product. Since the hydrogenated products of the ring-opening polymerization products of norbornene-based monomers have significantly different plasticization temperatures and decomposition temperatures from one another, they are suitable for calendered molding including heat. Therefore, this allows the molding of the film with good mechanical strength and good appearance.

Examples of norbornene-based monomers are described in paragraphs [0010] to [0013] in Japanese Patent Laid-Open No. 2001-9859 such as bicyclo [2.2.1] hept-2-ene (commonly referred to as norbornene). It includes the old ones.

These normonene monomers are used independently or in combination of two or more thereof. Among the norbornene-based monomers, dicyclopentadiene is preferably used at the bond. Examples of the bond include a combination of dicyclopentadiene and tetracyclododecene, a combination of dicyclopentadiene, tetracyclododecene and ethyltetracyclododecene, a combination of dicyclopentadiene and ethyltetracyclododecene, dicyclo Bonds of pentadiene and ethylidenetetracyclododecene, and bonds of dicyclopentadiene and 1,4-methano-1,4,4a, 9a-tetrahydrofluorene.

Examples of vinyl compounds copolymerizable with norbornene-based monomers include ethylene, propylene, 1-butene, 1-pentene, 1-hexene, 3-methyl-1-butene, 3-methyl-1-pentene, 3-ethyl-1 -Pentene, 4-methyl-1-pentene, 4-methyl-1-hexene, 4,4-dimethyl-1-hexene, 4,4-dimethyl-1-pentene, 4-ethyl-1-hexene, 3-ethel Α containing 2 to 20 carbon atoms, such as 1-hexene, 1-octene, 1-decene, 1-dodecene, 1-tetradecene, 1-hexadecene, 1-octadecene, and 1-ecogen -Olefins or ethylene; Cyclobutene, cyclopentene, cyclohexene, 3,4-dimethylcyclopentene, 3-methylcyclohexene, 2- (2-menylbutyl) -1-cyclohexene, cyclooctene and 3a, 5, 6, 7a-tetrahydro Cycloolefins such as -4,7-methano-1H-indene; Non-polymeric dienes such as 1,4-hexadiene, 4-methyl-1,4-hexadiene, 5-methyl-1,4-hexadiene and 1,7-octadiene. Such vinyl compounds may be used independently or in combination of two or more thereof.

Processes for polymerizing norbornene-based monomers or copolymerizing norbornene-based monomers and copolymerizable vinyl compounds and processes for hydrogenating the product are not particularly limited, and may be performed by known methods.

(2) monocyclic olefin polymer

As the monocyclic olefin polymer, further polymerization products of monocyclic olefin monomers such as cyclohexene, cycloheptene, or cyclooctene disclosed in JP-A-66266216 may be used.

(3) cyclic conjugated diene polymer

As cyclic conjugated diene polymers, 1,2 of cyclic conjugated diene monomers such as cyclopentadiene and cyclohexadiene disclosed in JP-A-6-136057 and JP-A-7-258318 are disclosed. Or 1,4-addition polymerization product and hydrogenated product thereof may be used.

(4) a hydrocarbon-based polymer having an alicyclic structure in the side chain

As the hydrocarbon-based polymer, polymers of vinyl-alicyclic hydrocarbon monomers such as vinylcyclohexene or vinylcyclohexane, hydrogenated products thereof, and hydrogenated products of styrene-based polymers may be used.

The molecular weight of the cyclic polyolefin used in the present invention is appropriately selected according to its end use, and measured by gel permeation chromatography in a cyclohexane solution (or a toluene solution when the polymer resin is not dissolved in cyclohexane). Regarding propene, the number average molecular weight is generally 5,000 to 500,000, preferably 8,000 to 200,000, more preferably 10,000 to 100,000, and the weight average molecular weight is generally 10,000 to 1,000,000, preferably 15,000 to 500,000 and , More preferably, it is 20,000-200,000. MWD (weight average molecular weight / number average molecular weight) is generally 1.0-10, Preferably it is 1.0-6, More preferably, it is 1.1-4. The mechanical strength and formability of the membrane are well balanced with each other by adjusting the molecular weight within such range.

The glass transition temperature (Tg) of the cyclic polyolefin used in the present invention may be appropriately selected depending on its end use, preferably 50 to 200 ° C or more, more preferably 70 to 150 ° C or more, most preferably Is 80 to 120 ° C. When the Tg is lowered within this range, yellowing caused by oxidative deterioration of the film on the plasticizer of the resin in calendar molding becomes less likely to occur, and the final film obtains excellent thermal resistance.

Since the cyclic polyolefin used in the present invention has a temperature of 5% weight loss upon heating, the heating (measured under a nitrogen atmosphere in which the temperature increases at a rate of 5 ° C / min) is preferably at least 280 ° C, 350 C or more is particularly preferable. When the temperature of 5% weight loss due to heating of the cyclic polyolefin is within this range, decomposition of the resin is less likely to occur even when the resin temperature rises to a high temperature, and bubbles are formed within the final molding due to the decomposition of the resin. Molding failures such as can be avoided, such polyolefins being preferred.

The melt viscosity at 260 ° C. of the cyclic polyolefin used in the present invention is generally 1 × 10 ¹ to 1 × 10 ⁵ poises, preferably 1 × 10 ² to 1 × 10 ³ poise. If the melt viscosity is within this range, such polyolefin is preferred because the moldability of the membrane is well balanced with the mechanical strength of the membrane.

(additive)

In the cyclic polyolefins used in the present invention, other polymers, antioxidants, antidegradants, lubricants, light stabilizers, UV light absorbers, fillers, colorants, crosslinkers, curing agents, plasticizers, and forming agents, if necessary, may be independently or their It may be added in two or more bonds.

When various additives are added, they may be added in the production step of the cyclic polyolefin resin or in the kneading, mixing, or melting step of the cyclic polyolefin resin after the production of the resin.

When producing a cyclic polyolefin membrane, the cyclic polyolefin is melted by heating to a temperature higher than the glass transition temperature of the polyolefin which is 30 to 150 ° C, preferably 70 to 120 ° C. The method of melting by heating can be carried out according to a known method. For example, it can be carried out using an extruder or a kneader. Among the extruders, a strainer is preferred, which can filter the external components contained in the resin and can feed the compound roll with a constant temperature distribution to the calendar roll. The strainer has the same structure as that provided on the front side of the extruder, except for the wire mesh of approximately 20-mesh or more, preferably 60-mesh or more. As a special strainer, there is a strainer with a miter connected to a super-mixer.

In producing the cyclopolyolefin membrane, the molten resin enters the roll gap between parallelly arranged calender roll sets rotating in the reverse direction and enters the film formation. Two or more calendar rolls are provided and arranged in the same way that it is done with rubber or vinyl chlorine resin.

The method of arrangement includes three basic arrangements of vertical type, horizontal type, and inclined type, which may be connected to construct a Z type, an inverted L type, an I type, a camel bag type, or an M type. In addition, various combinations are possible by varying the number of rolls from 2 rolls to 10 and multiple rolls. In addition, as a device adhered to the calendar roll, a cooling roll, a carrying roll, a pressure roll may be used in combination. Specific examples are three pairs of two vertical rolls, two inclined rolls, three vertical rolls, four vertical coating rolls, two vertical and four reverse L type rolls, two vertical and two horizontal rolls, two Vertical rolls, four reverse L type and one cooling roll, five I type and one cooling roll, four camel bag type and one cooling roll, one pair of three vertical rolls, four reverse L type and two 4 pressure rolls, 4 Z type and 2 pressure rolls, 2 horizontal rolls, 3 reverse L type rolls, 4 vertical rolls, 4 reverse L type rolls, 4 camel bag type rolls, 3 vertical and 1 4 cooling rolls, 4 reverse L type and 1 cooling roll, 4 Z type and 1 cooling roll, 3 vertical and 1 caring roll, 4 Z type and 4 cooling rolls, and 4 reverse L type And five cooling rolls.

The temperature of the calender rolls (a set of rolls into which the molten resin was first introduced) varies somewhat depending on the rotational speed of the rolls, and in order to prevent the production of the yellow film, the upper limit of the temperature is generally 230 ° C., preferably Is 210 ° C., more preferably 200 ° C., while on the other hand, the lower limit of the temperature is generally 100 ° C., preferably 130 ° C., more preferably 160 ° C. in order to discourage the production of films with low flatness. . The temperature of the second and subsequent rolls is not particularly limited, but is generally set to the same degree or slightly lower than the temperature of the roll into which the molten resin was first introduced.

The film drawn through the gap between the calendar rolls has a thickness of several microns to several millimeters. The thickness of the film can be adjusted by selecting the calendar speed, roll temperature, and nip distance of the roll in the roll.

The film drawn through the gap between the calendar rolls is fed to a take-off roll, a cooling draw device, and a wind-up machine, and the final film is a light transmitting film of the present invention. Can be used as The film thus obtained preferably has a yellowing degree of 2 or less, particularly preferably 1 or less. The film obtained by the process of the present invention does not suffer yellowing and can therefore be suitably used for optical applications.

In order to improve the storage stability of the recording medium of the present invention, it is important to adjust the composition of the light transmitting layer and not to change the light transmitting property of the information recording layer or the light transmitting layer due to various external influences. Therefore, the surface of the medium preferably has a pencil hardness of at least 2H.

In order to improve the scratch resistance of the surface, for example, Japanese Laid-Open Patent Publication No. 2003-99982 describes the use of a silicone lubricant, a fluorine-containing lubricant, or a fatty acid ester lubricant in the outermost layer. However, this technique has the drawback that it is effective for the influence input in the direction which is approximately horizontal with respect to the surface, but insufficient for the influence input in the direction perpendicular to the surface.

Therefore, in order to improve the retention of the recording medium, it is necessary to increase the pencil hardness of the surface.

The pencil hardness is determined by the thickness of the pencil which does not form scratches on the surface under a load of 9.8 N using the test pencil specified in JIS-S-6006 according to the method of assessing the pencil hardness specified in JIS-K-5400. Can be.

As required pencil hardness, 2H or more is preferable and 3H or more is more preferable. In view of durability, the higher the pencil strength, the more preferable. When the surface has a pencil hardness of 3H to 4H, the retention of the recording medium is significantly increased. However, too high hardness increases the crazing and cracking tendency at the stage of manufacturing the recording medium, so about 3H to about 4H is preferable.

In order to obtain such a pencil hardness, it is preferable to have a hard coat layer on a light transmission film which contains the cured film formed with the curable composition containing an irradiation curable resin. Hereinafter, the film formed by coating a hard coat layer on the support of the light transmitting film of the present invention is referred to as a hard coat film. Examples of hard coat films used in the present invention include those described below:

(1) As the resin forming component of the layer described in Japanese Patent No. 1,815,116, a multifunctional acylate-based monomer and an inorganic filler of a powder such as alumina, silica or titanium, and a polymerization initiator designed to increase the hardness of the layer Hard coating film formed by coating a coating component on the support.

(2) A hard coating film comprising organic fine particles crosslinked with a photopolymerizable composition containing silica or alumina surface-treated with an alkoxysilane, described in Japanese Patent No. 1,416,240.

(3) The hard coat film described in Japanese Laid-Open Patent Publication No. 2000-52472, wherein the hard coat layer is composed of two layers, and fine silica particles are added to the first layer.

(4) The hard coat layer described in Japanese Patent Laid-Open No. 2000-71392 consists of two layers, the lower layer uses a curable resin layer composed of a mixture of a radical curable resin and a cation curable resin, and the upper layer is a radical Hard coating film containing only curable resin

(5) A hard coat film formed by melt kneading a filler and a resin and extrusion molding a mixture, as described in Japanese Laid-Open Patent Publication No. 2002-248619.

Such hard coatings described in the enumerations mentioned above are not sufficient in some cases to provide sufficient hardness. In this case, the desired hardness can be obtained by the following improvement in each film making technique.

(1) to increase the number of functional groups and the amount of inorganic filler or initiator of the multifunctional alkyl ester monomer.

(2) to increase the amount of the inorganic filler.

(3) to increase the amount of silica in the first layer.

(4) to increase the proportion of the radical curable resin.

(5) to increase the amount of filler.

In the present invention, it is preferable to use a hard coat film obtained by coating the hard coat layer of the following constitution on the light transmitting film of the present invention.

1. Hard coating layer formed by hardening curable composition containing curable resin and providing the hard coating layer which has a pencil hardness of 2H or more.

2. Hard coating layer formed by curing a curable composition comprising a curable resin having at least one fluorine atom and a silicon atom and a polymerizer to add antifouling properties, the surface of which provides a cured hard coat layer having a contact angle of at least 90 degrees with water. .

3. A hard coating layer as described in 1 or 2 above, having a surface elasticity of 4.0 GPa to 10 GPa.

4. The hard coating layer described in any one of 1 to 3 above, wherein the hard coating layer has a thickness of 10 μm to 60 μm.

5. The curable composition as described in any one of 1 to 4 above, wherein the curable composition is curable by irradiation with active energy rays and curable resin having a ring-opening polymerizer and / or two or more ethylenically unsaturated in one molecule. A hard coating layer containing curable resin which has a group.

6. The hard coat layer as described in the above 5, wherein the curable resin having a ring-opening polymerizer is a crosslinkable polymer having a repeating unit represented by the following structural formula (1).

In Structural Formula (1), R ¹ represents a hydrogen atom or an alkyl group containing 1 to 4 carbon atoms, P ¹ represents a monovalent, ring-opening polymerization group, and L ₁ represents a single group or a bonding group having a bivalent or more Indicates.

7. The hard coat layer as described in 5 or 6 above, wherein the ring-opening polymerizer is a cationic polymerizer.

The hard coat layer and the antifouling hard coat layer described in 1 to 7 are described in more detail below.

The layer coated on the hard coating film of the present invention (hereinafter simply referred to as "hard coating layer") is a hard coating layer formed by curing the curable composition. Curing may be caused by active energy ray polymerization or thermal polymerization, but from the viewpoint of productivity, curing by active energy ray is preferred. The surface of the hard coat layer of the present invention preferably has a pencil hardness of 2H or more, more preferably 3H or more. The contact angle of the surface with respect to water is preferably 90 degrees or more, more preferably 97 degrees or more, and the upper limit is preferably 150 degrees or less, and more preferably 130 degrees or less from the viewpoint of antifouling properties.

The contact angle of the surface of the hard coating layer with respect to water can be adjusted within the above-mentioned range by mixing a polymerizer having a curable resin or compound containing a fluorine atom and / or a silicon atom as an antifouling agent. The polymerizer is preferably a group which can be polymerized by irradiation with active energy rays.

Curable resin, containing a known fluorine-containing curable resin or silicone-containing curable resin or fluorine atom containing fluorine atoms and / or silicon atoms, used as antifouling agents, having active energy light and a polymerization group, and polymerizable with active energy light rays Curable resins having both a skeleton structure and a silicon-containing skeleton structure are used.

In addition, active energy ray-polymerized resins having a skeleton structure capable of being well compatible with the metal oxide particles dispersed in the curable resin or resin mainly constituting the hard coating layer and a skeleton structure having fluorine atoms and / or silicon atoms are preferred. .

Fluorine or silicone is allowed to exist on the surface of the hard coating layer by curing such curable resin to form a hard coating layer or an antifouling layer.

In addition, in this specification, the antifouling layer constitutes a part of the antifouling hard coating layer. However, for the sake of convenience of explanation, the antifouling layer is in some cases distinguished from the hard coating layer, but in such a case, the antifouling layer is included in the antifouling hard coating layer.

Specific examples of the curable resin described above, which are used in the hard coating layer as an antifouling agent, include polymers, block copolymers, or fluorine atoms or silicon atoms obtained by introducing monomers and acyl groups containing fluorine atoms or silicon atoms into the copolymer. Graft copolymers of monomers containing.

Examples of fluorine-containing monomers include hexafluoroisopropyl acrylate, heptadecafluorodecyl acylate, and perfluoroalkylsulfonamidoethyl acylate and perfluoroalkylamidoethyl acylate (meth Perfluoroalkyl group having an acylate.

Specific examples thereof include 2-perfluorooctylethyl methacrylate, 2-perfluorooctylethyl acrylate (manufactured by Nippon Mektron, Ltd.), M-3633, M- 3833, M-3633, and M-3833 (manufactured by Daikin Fine Chemical Research Institute): AFC-1000, AFC-2000, and FA-16 (Kyoeisha Chemical Co., Ltd.): and compounds with polymerizers, such as acyl compounds such as Megapack 531 (manufactured by Dainippon Ink and Chemicals Inc.).

As a fluorine-containing copolymer, a main chain contains only a carbon atom, and there exists a copolymer containing the polymer unit which has a fluorine-containing vinyl monomer polymerization unit and a (meth) acrylol group in a side chain. Specific examples thereof include a copolymer represented by the following structural formula (2):

In structural formula (2), Mf represents a chlorine-containing vinyl monomer, L represents a bonding group having 1 to 10 carbon atoms, m represents 0 or 1, X represents a hydrogen atom or a methyl group, and A is a single component Or a polymerization unit of any vinyl monomer composed of a plurality of components, and x. y. And z represent the mole% of the respective structures having 30 ≦ x ≦ 60, 40 ≦ y ≦ 80, and 0 ≦ z ≦ 65, respectively.

As the fluorine-containing vinyl monomer represented by Mf in the formula (2), a fluoro olpin (for example, fluoroethylene vinylidene fluoride, tetrafluoroethylene or hexafluoropropylene), partially or totally fluorinated ( (Meth) alkyl ester derivatives of acrilic acid (e.g., Viscoat 6FM (trade name; manufactured by Oscar Yuki Kagaku) and M-2020 (trade name; manufactured by Daikin)), perfluoroalkylsulphonic acid Methacrylamide and wholly or partially fluorinated vinyl ethers. Among them, perfluoroolefins are preferred, and hexafluoropropylene is particularly preferred in view of solubility, transparency and usability.

The copolymer of this invention has a polymerized unit which has a (meth) acrylol group as an essential component in the side chain. The method for injecting a (meth) acrylol group into the copolymer is not particularly limited, and examples thereof include (1) synthesizing a polymer having a nucleophilic group such as a hydroxyl group or an amino group, and (meth) acryl chlorine, ( Meth) acrylic anhydride or a method of activating a mixed acid of (meth) acrylic acid and methanesulphonic acid on a polymer, (2) (meth) acrylic acid on a catalyst such as sulfuric acid on a polymer having the above-mentioned nucleophilic group Method of activating (3) activating a compound having both an isocyanato group and a (meth) acrylol group, such as methacryloloxypropyl isocyanate, on a polymer having a nucleophilic group described above, (4) having an epoxy group A method of synthesizing a polymer and activating (meth) acryloic acid thereon, (5) an epoxy group, such as glycidyl methacrylate, and (meth A method of activating a compound having both a) acrylol groups on a polymer having a carboxyl group, and (6) polymerizing a vinyl monomer having a portion of 3-chloropropionate and carrying out dehydrochlorination. Among these methods, in the present invention, it is preferable to inject the (meth) acrylol group into the hydroxyl group-containing polymer by the method (1) or (2).

The film strength can be improved by increasing the composition ratio of the (meth) acrylol group-containing polymerized unit. The composition of the (meth) acrylol group-containing polymerized unit is preferably 40 to 80 mol%, more preferably 45 to 75 mol%, particularly preferably 50 to 70 mol%, but this is in accordance with the type of fluorine-containing vinyl monomer polymerized unit. Change accordingly.

In copolymers useful in the present invention, the vinyl monomers represented by A in Structural Formula (2) are fluorine-containing vinyl monomers in various respects such as solubility in solvents, transparency, lubrication properties, and dust- and anti-fouling properties. It may be copolymerized appropriately in addition to the polymerization unit having a (meth) acrylol group in the polymerization unit and the side chain. A plurality of such vinyl monomers may be bonded depending on their purpose, and are preferably entered in a composition of 0 to 65 mol%, more preferably 0 to 30 mol%, based on the copolymer.

The vinyl monomer units used in the bonds are not particularly limited, but examples thereof include olefins (eg, ethylene, propylene, isoprene, vinyl chloride, and vinylidene chloride), acrylates (eg, methyl acrylic Latex, enyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, 2-hydroxyethyl acrylate, glycidyl acrylate, allyl acrylate, and trimethoxysilylpropyl acrylate), methacrylate (example For example, methyl methacrylate, ethyl methacrylate, butyl methacrylate, 2-ethylhexyl methacrylate, 2-hydroxyethyl methacrylate, glycidyl (CH ₂ ) ₂ -NH-**, *-(CH ₂ ) ₄ -O-**, *-(CH ₂ ) ₆ -O-**, *-(CH ₂ ) ₂ -O- (CH ₂ ) ₂ -O-**, * -CONH -(CH ₂ ) ₃ -O-**, * -CH ₂ CH (OH) CH ₂ -0-**, and * -CH ₂ CH ₂ OCONH (CH ₂ ) ₃ -O-** (* is the main Indicates the binding position on the chain side And ** represents a bonding position on the (meth) acrylol group side.) M represents 0 or 1.

In structural formula (2), X represents a hydrogen atom or a methyl group. From the curing reactivity point of view, X preferably represents a hydrogen atom.

x, y, and z represent the mole% of the respective configurations of 30 ≦ x ≦ 60, 40 ≦ y ≦ 80, and 0 ≦ z ≦ 65, respectively. The range is preferably 35 ≦ x ≦ 55, 45 ≦ y ≦ 75, and 0 ≦ z ≦ 20, particularly preferably 40 ≦ x ≦ 55, 50 ≦ y ≦ 70, and 0 ≦ z ≦ 10.

Examples of the silicone-containing monomer include a monomer having a siloxane group obtained by reacting polydimethylsiloxane with (meth) acrylic acid. Specific examples of the siloxane compound having a terminal (meth) acrylate include X-22-164A, X-22-164B, X-22-164C, X-22-2404, X-22-174D, and X-22-8201. , And X22-2426 (manufactured by Shin-Etsu Chemical Company).

Curable composition which contains a compound which has at least one of a fluorine atom and a silicon atom, and has at least one of a fluorine atom and a silicon atom, and does not contain the compound which has an active energy ray polymerizer, and contains a compound which has an active energy ray polymerizer. In the case of a hard coat film which is a layer, the thickness of the curable composition layer containing at least one of a fluorine atom and a silicon atom and containing a compound having an active energy ray polymerizer is preferably 0.05 µm to 2 µm. If the thickness is too small, sufficient film strength and sufficient antifouling effect cannot be obtained. On the other hand, if it is larger than 1 μm, the thickness is preferably 0.1 μm to 1 μm because the technical importance of the multilayer structure is reduced.

The polymerizable group by irradiation of active energy rays may be added by introducing a radical polymerizable double bond such as an acyl group or a cationic polymerizer such as an epoxy group. In the curable composition, the content of the compound having a silicon atom and an active energy ray polymerizer is preferably 0.01 to 20% by weight, more preferably 1 to 15% by weight, based on the curable resin.

In order to obtain good damage resistance of the hard coating layer, the hard coating layer has a constant hardness grade. From the viewpoint of hardness, the surface elastic modulus of the hard coat layer is preferably about 4.0 GPa or more, and more preferably 4.5 GPa or more. Hard coating layers having a surface modulus of less than 4.0 GPa fail to provide sufficient pencil hardness and sufficient damage resistance. In addition, from the standpoint of universal hardness, the surface elastic modulus is preferably about 250 N / mm ² or more, and more preferably 300 N / mm ² or more.

Surface elastic modulus can be increased by adding inorganic fine particles. If too much inorganic fine particles are added, brittleness may become serious, so the upper limit of the surface modulus is 10 Gpa, preferably 9.0 Gpa. Therefore, the surface elastic modulus is preferably within the range of 4.0 to 10 Gpa, particularly preferably within the range of 4.5 to 9.0 Gpa.

As a result of experiments to obtain both sufficient pencil hardness and sufficient brittleness of the hard coating layer, it has been found that it is effective to coat hard coatings that provide a slightly lower hardness but provide improved brittleness.

Surface modulus is a value determined using a micro surface hardness meter (Fischer Instrument; manufactured by Fisher Scope H100VP-HCU). Specifically, the modulus of elasticity is determined using a tetragonal pyramid indenter made of diamond (angle between the indenter nt and the opposite side: 136 °), in which the indentation depth is adjusted under a suitable test rod with an indentation depth of 1 μm or less. Measure and determine the modulus of elasticity from replacement with changes in rod and removal of rod.

   It is also possible to determine the surface hardness as a universal hardness using the micro surface hardness tester described above. Universal hardness is a value obtained by measuring the indentation depth of a tetragonal pyramid indenter under a test rod and dividing the test rod by the surface area of the tread generated under the test rod (the width calculated on the geometric pattern of the tread).

It is known that there is a positive correlation between surface modulus and universal hardness.

10 micrometers or more are preferable and, as for the thickness of the hard coat layer of this invention, 20 micrometers or more are more preferable. When the thickness of the hard coating layer increases too much, it becomes difficult to bend the film thus formed, and cracking tends to occur as the bending occurs. Therefore, 60 micrometers or less are preferable and, as for the thickness of a hard coat layer, 50 micrometers or less are more preferable. Therefore, the thickness of the hard coat layer is preferably 10 to 60 µm, more preferably 20 to 50 µm.

The hard coat layer may consist of a single layer or a plurality of layers, but a single layer is preferred because of the simple and easy operation of the manufacturing step. Here, a single layer means a hard coating layer formed by curing one and the same curable composition, and may be formed by coating the composition a plurality of times as long as the composition exhibits the same formula after coating and drying subsequent to curing. On the other hand, the hard coating layer composed of a plurality of layers means a layer formed by coating and curing a plurality of different curable compositions in the formula.

The hard coating layer of the present invention may be formed by coating a curable composition that can be cured by irradiation with active energy light, and then curing the composition by irradiation with active energy light. The cure shrinkage rate of the curable composition by irradiation with active energy rays is 0 to 15%, preferably 1 to 13%, more preferably 0 to 11%.

The cure shrinkage rate is a value determined by measuring the density of the curable composition before irradiation with active energy light such as UV light and the density of the curable composition after irradiation with active energy light, and calculating it according to numerical formula A using the density. In addition, the density was measured at 25 ° C. with a MULTIVOLUME PYCNOMETER (manufactured by Micrometric Corporation).

Formula A:

Volume reduction = {1- (density before cure / density after cure)} × 100

The curable composition for forming the hard coat layer is a main component and differs from the curable resin which functions as an antifouling agent and contains a curable resin that can be cured by active energy light or heat. The curable composition (also referred to hereinafter simply as the "curable composition") for forming the hard coating layer is a curable resin having a curable resin having a ring-opening polymerizer and / or two or more (more preferably three or more) ethylenically unsaturated groups. It is preferable to include curable resin which has a molecule. It is more preferable to contain both curable resins, whereby the surface hardness of the hard coat layer increases a lot, whereby a hard coat film having excellent damage resistance can be obtained. At the same time, the volume reduction falls within the range described above, the curling after curing is reduced, and cracks due to various handling are less likely to occur. In addition, by adjusting the thickness of the hard coating layer to a limited thickness, the above-described effect is more pronounced.

Curable resin containing a ring-opening polymerization group and preferably used in the present invention is described below.

Curable resin containing a ring-opening polymerizer is curable resin which has a cyclic structure which undergoes ring-opening polymerization by the activity of a cation, an anion, or a radical. Among them, heterocyclic group-containing curable resins are preferable. Examples of such curable resins include cyclic iminoether derivatives such as epoxy derivatives, oxetane derivatives, tetrahydrofuran derivatives, cyclic lactone derivatives, cyclic carbonate derivatives, and oxazoline derivatives, epoxy derivatives, Particular preference is given to oxetane derivatives, and oxazoline derivatives.

In the present invention, the curable resin having a ring-opening polymerizer preferably has two or more, more preferably three or more ring-opening polymerizers in the molecule. Moreover, in this invention, you may use combining two or more types of curable resin which has a ring-opening polymerization group. In this case, the curable resin having one ring-opening polymerizer in the molecule and the curable resin having two or more ring-opening polymerizers in the molecule may be bonded to each other, or two or more curable resins having two or more ring-opening polymerizers in the molecule may be used in combination. It may be.

Curable resin which has a ring-opening polymerization group is not specifically limited as long as it has the above-mentioned cyclic structure. Preferred examples of the curable resins include monofunctional glycidyl ethers, monofunctional alicyclic epoxy derivatives, bifunctional alicyclic epoxy derivatives, diglycidyl ethers (e.g., ethylene glycol diclisidyl ethers and non Phenol A diglycidyl ether), glycidyl ethers having three or more functional groups (eg, trimethylolethane triglycidyl ether, trimethylolpropane triglycidyl ether, glycerol triglycidyl ethyr, and tris (glycyl) Cydyloxyethyl) isocyanurate), glycidyl ethers having four or more functional groups (e.g., sorbitol tetraglycidyl ether, pentaerythritol tetraglycidyl ether, cresol novolac resin polyglycidyl ether , And phenol novolac resin polyglycidyl ether), alicyclic epoxy derivatives (Ceroxide 2021P, Ceroxide 2081, Epolead GT-301, Epolead GT-401 (Diesel) Manufactured by Daicel Chemical Industries, Ltd ,.), EHPE (manufactured by Daicel Chemical Industries, Ltd ,.), and phenol novolak resin polycyclohexylepoxymethyl ether) , And oxetane (OX-SQ and PNOX-1009 manufactured by Toagosei Co., Ltd.). However, the present invention is not limited only to these.

In the present invention, it is particularly preferable that the curable resin having a ring-opening polymerizer include a crosslinkable polymer having a repeating unit represented by Structural Formula (1). Crosslinkable polymers are described below.

In structural formula (1), R ¹ represents a hydrogen atom or an alkyl group containing 1 to 4 carbon atoms, preferably a hydrogen atom or a methyl group. L ¹ is a single bond or a bivalent or more bonding group, preferably a single bond, -O-, an alkylene group, and * -COO-, * -CONH-, * -OCO-, or * -NHCO- (* is Indicates the position of binding to the main chain). P ¹ represents a monovalent group having a monovalent ring-opening polymerizer or a ring-opening polymerizer. Preferred examples of P ¹ include monovalent groups having an iminoether ring such as an epoxy ring, an oxetane ring, a tetrahydrofuran ring, a lactone ring, a carbonate ring, or an oxazoline ring. Among these, the monovalent group which has an epoxy ring, an oxetane ring, or an oxazoline ring is especially preferable.

In the present invention, the crosslinkable polymer containing the repeating unit represented by the structural formula (1) is preferably synthesized by polymerizing the corresponding monomer. As the polymerization reaction employed here, radical polymerization is the simplest and most preferred.

Specific preferred examples of the repeating unit represented by Structural Formula (1) are described below, but do not limit the present invention.

In the present invention, the crosslinkable polymer comprising the repeating unit represented by formula (1) may be a copolymer composed of a plurality of repeating units represented by formula (1), or in formula (1) It may be a copolymer containing other repeating units (for example, repeating units not containing a ring-opening polymerizer) other than the repeating unit represented by the above. In particular, in the case of controlling the hydrophilicity or hydrophobicity of the Tg or the crosslinkable polymer, or for controlling the content of the ring-opening polymerizer in the crosslinkable polymer, other repeating units other than the repeating unit represented by Structural Formula (1) Techniques using a copolymer having The addition of repeating units other than the repeating unit represented by formula (1) is preferably carried out by copolymerizing the corresponding monomers.

In the case where a repeating unit other than the repeating unit represented by the structural formula (1) is added by copolymerization to a corresponding vinyl monomer, examples of the monomers preferably used include acrylic acid or α-alkylacrylic acid (for example, Esters derived from methacrylic acid (eg, methyl acrylate, ethyl acrylate, hydroxyethyl acrylate, n-propyl acrylate, isopropyl acrylate, 2-hydroxypropyl acrylate, 2-methyl 2-nitropropyl acrylate, n-butyl acrylate, isobutyl acrylate, tertbutyl acrylate, tertpentyl acrylate, 2-methoxyethyl acrylate, 2-ethoxyethyl acrylate, 2-methoxymethoxy Methoxyethyl acrylate, 2,2,2-trifluoroethyl acrylate, 2,2-dimethylbutyl acrylate, 3-methoxybutyl acrylate, ethyl Levitol acrylate, phenoxyethyl acrylate, n-pentyl acrylate, 3-pentyl acrylate, octafluoropentyl acrylate, n-hexyl acrylate, cyclohexyl acrylate, cyclopentyl acrylate, cetyl acrylate, Benzyl acrylate, n-octyl acrylate, 2-ethylhexyl acrylate, 4-methyl-2-propylpentyl acrylate, heptadecafluorodecyl acrylate, n-octadecyl acrylate, methyl methacrylate, 2, 2,2-trifluoroethyl methacrylate, tetrafluoropropyl methacrylate, hexafluoropropyl methacrylate, hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, n-butyl methacrylate Isobutyl methacrylate, sec-butyl methacrylate, n-octyl methacrylate, 2-ethylhexyl methacrylate, 2-methoxy Methacrylate, 2-ethoxyethyl methacrylate, benzyl methacrylate, heptadecafluorodecyl methacrylate, n-octadecyl methacrylate, 2-isobornyl methacrylate, 2-norbornylmethyl methacrylate Acrylate, 5-norbornene-2-ylmethyl methacrylate, 3-methyl-2-norbornylmethyl methacrylate, and dimethylaminoethyl methacrylate), acrylic acid or α-alkylacrylic acid (eg For example, amides derived from methacrylic acid (eg, Ni-propylacrylamide, Nn-butylacrylamide, Nt-butylacrylamide, NN-dimethylacrylamide, N-methylmethacrylamide, acrylamide, 2-acrylamido-2-methylpropanesulphonic acid, acrylamidopropyltrimethylammonium chloride, methacrylamide, diacetoneacrylamide, acrylomorpholine, N-methylolacrylamide, and N-methylolmetha Esters derived from krillamide), acrylic acid or α-alkylacrylic acid (eg, acrylic acid, methacrylic acid, and itaconic acid), vinyl esters (eg vinyl acetate), maleic acid or fumaric acid (Eg, dimethyl maleate, dibutyl maleate, and diethyl fumarate), maleimide (eg N-phenylmaleimide), maleic acid, fumaric acid, p-styrenesulphonic acid sodium salt, acrylic Ronitrile, methacrylonitrile, dienes (eg butadiene, cyclopentadiene, and isopropene), aromatic vinyl compounds (eg styrene, p-chlorostyrene, t-butylstyrene, α-methylstyrene , And sodium styrenesulfonate), N-vinylpyrrolidone, N-vinyloxazolidone, N-vinylsuccinimide, N-vinylformamide, N-vinyl-N-methylformamide, N-vinylacetamide , N-vinyl-N-methylacetamide, 1-vinylimidae , 4-vinylpyridine, vinylsulphonic acid, sodium vinylsulfonate, sodium allylsulfonate, sodium metalylsulfonate, vinylidene chloride, vinyl alkyl ethers (eg methyl vinyl ether), ethylene, propylene, 1-butene And isobutene.

These vinyl monomers may be used in combination of two or more. As other vinyl monomers, those described in Survey Specification No. 19551 (1980, July) may be used.

Among these, amides and esters derived from acrylic acid or methacrylic acid, and aromatic vinyl compounds are particularly preferably used.

As a repeating unit other than the repeating unit represented by Structural Formula (1), a repeating unit having a reactor other than the ring-opening polymerizer may be added. In particular, when improving the hardness of the hard coating layer and increasing the adhesion between the hard coating layer and other working layers (provided on the hard coating layer), a technique using a copolymer containing a reactor other than the ring-opening polymerizer is suitable. Do. Putting a repeating unit having a reactor other than the ring-opening polymerizer is preferably carried out by copolymerizing the corresponding vinyl monomer (hereinafter referred to as "reaction monomer").

Specific examples of the reaction monomers are described below, but do not limit the present invention.

Examples thereof include hydroxyl group-containing vinyl monomers (eg, hydroxyethyl acrylate, hydroxyethyl methacrylate, allyl alcohol, hydroxypropyl acrylate, and hydroxypropyl methacrylate), isocyanato groups Containing vinyl monomers (e.g. isocyanatoethyl acrylate and isocyanatoethyl methacrylate), N-methylol group-containing vinyl monomers (e.g., N-methylol acrylamide and N-methylol meta Acrylamide), carboxyl group-containing vinyl monomers (eg, acrylic acid, methacrylic acid, itaconic acid, carboxyethyl acrylate, and vinyl benzoate), alkyl halogen-containing vinyl monomers (eg, chloromethylstyrene and 2-hydroxy-3-chloropropyl methacrylate, acid anhydride containing vinyl monomers (eg maleic anhydride), formyl group containing vinyl Monomers (eg acrolein and methacrolein), sulfonic acid group-containing vinyl monomers (eg potassium styrenesulfinate), active methylene-containing vinyl monomers (eg acetoacetoxyethyl methacrylate), acid chlorides Containing monomers (eg, acrylates and methacrylates), amino group-containing monomers (eg, allylamine), and alkoxysilyl group-containing monomers (eg, methacryloyloxypropyltrimethoxysilane and Acryloyloxypropyltrimethoxysilane).

In the present invention, the proportion of the repeating unit represented by the structural formula (1) in the crosslinkable polymer containing the repeating unit represented by the structural formula (1) is 1% by weight to 100% by weight, and 30% by weight to 100%. Weight percent is preferred, with 50% to 100% by weight being particularly preferred.

The number average molecular weight (measured by gel permeation chromatography with polyethylene glycol) of the crosslinkable polymer containing the repeating unit represented by Structural Formula (1) preferably has a range of 1,000 to 1,000,000, and 3,000 to 200,000 Is more preferable and 5,000-100,000 are the most preferable.

Preferred examples of crosslinkable polymers containing repeating units represented by Structural Formula (1) are shown in Table 1, but do not limit the invention. In addition, the repeating unit represented by the structural formula (1) and described above is represented by the number given above, the repeating unit derived from the copolymerizable monomer is represented by its name, and the copolymerization composition ratio is expressed by weight%.

As described above, the curable composition cured by irradiation with active energy light in order to form a hard coat layer preferably comprises a curable resin having a curable resin comprising a ring-opening curing group and a molecule having two isoethylenically unsaturated groups ( That is, both curable resins having two or more ethylenically unsaturated groups in a molecule) are included.

Curable resins having two or more ethylenically unsaturated groups in a molecule are described in detail below.

Preferable examples of the ethylenically unsaturated group are an acrylol group, a methacrylol group, a styryl group, and a vinyl ethyr group, and an acrylic group is particularly preferable.

In addition, the curable resin (monomer or oligomer) containing one or two ethylenically unsaturated groups may be combined with the curable resin containing two or more ethylenically unsaturated groups in a molecule.

In addition, multifunctional acrylate monomers having 2 to 6 acrylates in the molecule and oligomers having a plurality of acrylate groups in the molecule and having molecular weights of several hundred to thousands, and called urethane acrylates, polyester acrylates, or epoxy acrylates May be preferably used as the curable composition of the present invention.

Specific examples of the curable resin having two or more acrylic groups in the molecule include ethylene glycol diacrylate, 1,6-hexanediol diacrylate, bisphenol A diacrylate, trimethylolpropane triacrylate, and ditrimethylolpropane tetraacrylic. Polyol polyacrylates such as latex, pentaerythritol triacrylate, pentaerythritol tetraacrylate, dipentaerythritol pentaacrylate, and dipentaerythritol hexaacrylate; And urethane acrylates obtained by reaction between polyisocyanates and hydroxyl group-containing acrylates such as hydroxyethyl acrylate. More preferable are curable resins having two or more acrylic groups in the molecule.

In addition, in this invention, the crosslinkable polymer which has a repeating unit represented by Structural formula (3) is also preferably used as curable resin which has two or more ethylenically unsaturated groups in a molecule | numerator. Crosslinkable polymers having repeating units represented by structural formula (3) are specifically described below.

In structural formula (3), R <^2> represents a hydrogen atom or the alkyl group of 1-4 carbon atoms, and a hydrogen atom or a methyl group is preferable.

P ² represents a monovalent group having a monovalent ethylenically unsaturated group or an ethylenically unsaturated group.

L ² is a single bond or a bivalent or more bonding group, preferably a single bond, -O-, an alkylene group, an arylene group, and * -COO-, * -CONH-. * -OCO- or * -NHCO- is represented.

Preferred P ² comprises, for example, an acrylol group, a methacrylol group, a styryl group, or a monovalent group comprising any of these groups, and most preferably a monovalent group containing an acrylol group or the same.

The crosslinkable polymer containing the repeating unit represented by Structural Formula (3) polymerizes a monomer having any functional group by (i) a method of directly inputting by polymerizing a corresponding monomer or (ii) a polymerization reaction. It can also be synthesize | combined by the method of adding an ethylenically unsaturated group to the obtained polymer. In addition, the synthesis may be carried out by a combination of the methods (iii) and (ii). The polymerization reaction may include, for example, radical polymerization, cationic polymerization, and anionic polymerization.

When employing process (iii), the synthesis can be carried out by taking advantage of the difference in degree of polymerization between the ethylenically unsaturated groups consumed in the polymerization reaction and the ethylenically unsaturated groups remaining in the crosslinkable polymer. For example, when P ² of Structural Formula (3) is a monovalent group containing an acrylol group, methacrylol group, or ether thereof, the crosslinkable polymer of the present invention may be prepared by employing cationic polymerization for polymerization reaction. I) can be obtained by On the other hand, when P ² is a monovalent group containing a styryl group or a styryl group, since the gelation tends to proceed by any of radical polymerization, cationic polymerization, and anionic polymerization methods, the crosslinkable polymer of formula (3) is Synthesized generally by the described method (ii).

As explained above, the method (ii) using the polymerization reaction is useful because crosslinkable polymers can be obtained regardless of the type of ethylenically unsaturated groups introduced in the structural formula (3).

The polymerization reaction forms, for example, a polymerizer containing a functional group formed from an ethylenically unsaturated group in a precursor such as separating hydrogen chloride from a 2-chloroethyl group, and then functional group conversion (separation action, oxidation action, and reduction). Functional group and ethylenic group to form a polymer comprising an optional functional group (I) and an optional functional group, and then undergo a bond forming reaction with a functional group to form a covalent bond in the polymer. The method (II) which reacts the reactive monomer which has both unsaturated groups is included. Methods (I) and (II) can be combined.

For the bond formation reactions mentioned herein, among the bond formation reactions generally used in the field of organic synthesis, covalent bond formation reactions can be used without particular reaction. On the other hand, since the ethylenically unsaturated groups contained in the crosslinkable polymer are often thermally polymerized and gelled, it is preferable to proceed with the reaction at the lowest possible temperature (preferably below 60 ° C, particularly preferably below room temperature). In addition, catalysts may also be used for the purpose of promoting the course of the reaction, and polymerization inhibitors may also be used for the purpose of inhibiting gelation.

Examples of the bonding of functional groups undergoing a preferred polymer bond forming reaction are mentioned below, but not limited thereto.

Combinations of functional groups for heating or conducting the reaction at room temperature may be included below.

(Iii) hydroxyl group, epoxy group, isocyanate group, N-methylol group, carboxyl group, alkyl halide, acid anhydride, acid chloride, active ester group (e.g. sulfate ester), formyl group, or acetal group,

(Ii) an isocyanate group, a hydroxyl group, a mercapto group, an amino group, a carboxyl group, or an N-methylol group,

(Iii) a carboxyl group, an epoxy group, an isocyanate group, an amino group, or an N-methylol group,

(Iii) an N-methylol group, an isocyanate group, an N-methylol group, a carboxyl group, an amino group, or a hydroxyl group,

(Iii) an epoxy group, a hydroxyl group, an amino group, a mercapto group, a carboxyl group, or an N-methylol group,

(Iii) a vinyl sulfonic group, a sulfonic acid group, or an amino group,

(Iii) a formyl group, a hydroxyl group, a mercapto group, or an active methylene group,

(Iii) mercapto groups, formyl groups, vinyl groups (allyl groups, acrylic groups, etc.), epoxy groups, isocyanate groups, N-methylol groups, carboxyl groups, alkyl halides, acid anhydrides, acid chlorides, or active ester groups (for example , Sulfate esters)

(Iii) amino groups, formyl groups, vinyl groups (allyl groups, acryl groups, etc.), epoxy groups, isocyanate groups, N-methylol groups, carboxyl groups, alkyl halides, acid anhydrides, acid chlorides, or active ester groups (e.g. Pate ester).

Preferred examples of the reactive monomers are shown below, but the present invention is not limited thereto.

Preferred examples of reactive monomers include, for example, hydroxyl-containing vinyl monomers (eg hydroxyethyl acrylate, hydroxyethyl methacrylate, allyl alcohol, hydroxypropyl acrylate, hydroxypropyl methacrylate, Etc.), isocyanate-containing vinyl monomers (eg, isocyanate ethyl acrylate, isocyanate ethyl methacrylate, etc.), N-methylol-containing vinyl monomers (eg, N-methylol acrylamide, N-methylol meta Krillamide, etc.), epoxy containing vinyl monomers (e.g., glycidyl acrylate, glycidyl methacrylate, allylglycidyl ether, CYCLOMER-M1000, A200 (manufactured by Daicel Chemical)) , Carboxyl-containing vinyl monomers (eg, acrylic acid, methacrylic acid, itaconic acid, carboxyethyl acrylate, and vinyl benzoate) ), Alkyl halide containing vinyl monomers (e.g. chloromethyl styrene and 2-hydroxy-3-chloropropyl methacrylate), acid anhydride containing vinyl monomers (e.g. maleic anhydride), formyl containing vinyl monomers (Eg, acrolein and metagrolane), sulfonic acid-containing vinyl monomers (eg potassium styrene sulfinate), active methylene-containing vinyl monomers (eg acetoacetoxy ethyl methacrylate), vinyl-containing Vinyl monomers (eg allyl methacrylate and allyl acrylate), acid chloride containing monomers (eg acrylate and methacrylate), and amino containing monomers (eg allylamine).

The polymer containing any functional group described in (II) above can be obtained by carrying out polymerization of a reactive monomer having both a reactive functional group and an ethylenically unsaturated group. The polymer can also be obtained by carrying out the polymerization of low reactive precursor monomers such as polyvinyl alcohol obtained by modifying the polyvinyl acetate and subsequently by the conversion of functional groups.

In the case described above, as the polymerization method, radical polymerization is most preferably simple and convenient.

Preferred examples of the repeating unit represented by general structural formula (3) are shown below, but the present invention is not limited thereto.

In the present invention, the crosslinkable polymer containing the repeating unit represented by the structural formula (3) may be a copolymer composed of a plurality of repeating units represented by the structural formula (3), and is represented by the structural formula (3) It may also be a copolymer containing other repeating units (eg, repeating units not containing an ethylenically unsaturated group) other than the repeating units. In particular, in the case of controlling Tg or hydrophobicity or hydrophilicity, or for controlling the composition of ethylenically unsaturated groups in a crosslinkable polymer, air containing other repeating units other than the repeating units represented by formula (3) Preference is given to a method of forming coalescing. As a method for introducing a repeating unit other than the repeating unit represented by the structural formula (3), (a) a method of directly injecting by copolymerizing the corresponding monomer may be used, and (b) a precursor which can be converted into a functional group. Methods of polymerizing monomers and introducing into the polymeric reaction may also be used. In addition, it can combine and input method (a) and (b).

When polymerizing the corresponding vinyl monomer by the method (a), when putting a repeating unit other than the repeating unit represented by Structural formula (3), the monomer used preferably is in the description about the said Structural formula (1) Monomers consistent with those mentioned as being preferably used in the case where a repeating unit other than the repeating unit represented by Structural Formula (1) are put by polymerization of the corresponding vinyl monomer. Two or more such vinyl monomers may be used in combination. As other vinyl monomers not described above, those described in Research Publication No. 19551 (1980, July) can be used. Among them, esters and amides derived from acrylic acid or methacrylic acid, and aromatic vinyl compounds are particularly preferably used.

In addition, when the repeating unit represented by the structural formula (3) is added to the polymer reaction and the reaction described in the above (ii) is not terminated, it is a repeat containing a functional group formed from an ethylenically unsaturated group as a precursor or a reactive group. It forms a copolymer with units, which can be used without particular limitation in the present invention.

Most repeating units that do not contain ethylenically unsaturated groups derived from the vinyl monomers described above can be entered by (b) polymerizing precursor monomers that can be converted into functional groups, and by polymeric reactions. On the other hand, the crosslinkable polymer containing the repeating unit represented by the structural formula (3) in the present invention may also include other repeating units other than the general structural formula (3) which can be introduced only by the polymeric reaction. Typical examples may include polyvinyl alcohol, obtained by modifying vinyl acetate and polyvinyl butyral, obtained by modification of polyvinyl acetate and polyvinyl butyral, obtained by the acetalization reaction of polyvinyl alcohol. Specific examples of repeating units are shown below, but the present invention is not limited thereto.

In the crosslinkable polymer containing the repeating unit represented by the formula (3) in the present invention, the content ratio of the repeating unit represented by the formula (3) is 1% by weight to 100% by weight, preferably 30% by weight. To 100% by weight, particularly preferably 50% to 100% by weight.

The number average molecular weight (measured by gel permeation chromatography in polystyrene glycol) of the crosslinkable polymer containing the repeating unit represented by the formula (3) is preferably 1,000 to 1,000,000, more preferably 3,000 to It is within the range of 200,000. 5,000 to 100,000 are most preferred.

Preferred examples of crosslinkable polymers containing repeating units represented by formula (3) are shown in Table 2. The present invention is not limited thereto. The repeating units mentioned previously as specific examples, such as the repeating units represented by the structural formula (3) and polyvinyl alcohol, are represented by the numbers of the specific examples described above, while the repeating units derived from the copolymerizable monomer are described by the name of the monomer, The copolymer composition ratio is attached in weight percent.

Moreover, curable resin containing the ring-opening polymerization group which can be used by this invention contains the polymer containing both repeating units represented by structural formula (1) and (3). In this case, the preferred repeating units represented by the structural formula (1) or (3) agree with those described above. Furthermore, it is a copolymer containing a repeating unit other than the repeating unit represented by the structural formula (1) or (3), or a copolymer containing a repeating unit having a reactive group other than the ethylenically unsaturated group and the ring-opening polymerizable group. It may be.

The proportion of the repeating unit represented by the structural formula (1) contained in the crosslinkable polymer containing both repeating units represented by the structural formulas (1) and (3) is 1% by weight to 99% by weight, preferably 20 Wt% to 80 wt%, particularly preferably 30 w% to 70 wt%. The proportion of the repeating unit represented by the structural formula (3) contained therein is 1% by weight to 99% by weight, preferably 20% by weight to 80% by weight, particularly preferably 30% by weight to 70% by weight. .

The weight average molecular weight (measured by gel permeation chromatography in polyethylene glycol) of the crosslinkable polymer containing both repeating units represented by the structural formulas (1) and (3) is preferably 1,000 to 1,000,000, more preferably Is in the range of 3,000 to 200,000. 5,000 to 100,000 are most preferred.

Table 3 shows a preferred example of a crosslinkable polymer comprising both repeating units represented by structural formulas (1) and (3), but the present invention is not limited thereto. The repeating units mentioned in the specific examples described above, such as the repeating units represented by the structural formula (1) or (3) and polyvinyl alcohol, are represented by the numbers of the specific examples described previously, and the repeating units derived from the copolymerizable monomers are monomers. Illustrated in the name of, the copolymer composition ratio is attached in weight percent.

The preferred mixing ratio between the curable resin containing two or more ethylenically unsaturated groups in the molecule and the curable resin including the ring-opening polymerizer included in the curable composition to form a hard coat layer may vary depending on the type of curable resin used. Is not particularly limited. It is preferable that the ratio of curable resin containing an ethylenically unsaturated group is 30 weight%-90 weight%, More preferably, it is 50 weight%-80 weight% based on total curable resin.

In the case of curing a curable composition comprising a curable resin containing an ethylenically unsaturated group and a curable resin containing a ring-opening polymerizer ("curable composition" is a composition containing both curable resins unless otherwise stated), a crosslinking reaction. It is preferable to advance with respect to both silver curable resin. Preferred crosslinking reactions for ethylenically unsaturated groups are radical polymerizable reactions, while preferred crosslinking reactions for ring-opening polymerizable groups are cationic polymerization reactions. In each case, the polymerization reaction can proceed by the effect of actinic energy light. In general, the polymerization can proceed by adding a small amount of a radical generator and a cation generator (or acid generator) called a polymerization initiator, and decomposing them into actinic energy light to generate radicals and cations. The radical polymerization and the cationic polymerization may be carried out separately, but preferably proceed simultaneously.

When curing the curable composition by irradiation of actinic energy light, the crosslinking reaction often proceeds preferably at low temperatures.

In the present invention, irradiation light, γ-rays, α-rays, electron beams, or UV-rays are used as actinic energy light. Especially, the method of using UV-ray which adds the polymerization initiator which generate | occur | produces a radical or a cation and hardens the same thing with UV-ray is especially preferable. In addition, the curing may sometimes proceed by heating after irradiation of UV-rays, the method being preferably used. In this case, preferable heating temperature is 140 degrees C or less.

Optical acid generators which generate cations by UV-ray irradiation include curable resins of ions such as triaryl sulfonium salts or diaryl indonium salts and nonionic curable resins such as nitrobenzyl esters of sulfonic acids, for example Various optical acid generators can be used, such as curable resins, edited by the Organic Electronic Materials Study Group, and described in "Organic Material for Imaging" published by Bunshin Co., Ltd. (1997). Of these, sulfonium salts or indonium salts are particularly preferred, and PF ₆ ⁻ , SbF ₆ ⁻ , AsFe ⁻ , and B (C ₆ F ₅ ) ₄ ⁻ are preferred as counterions.

Examples of polymerization initiators for generating radicals with UV-rays include acetophenones, benzophenones, myhilerketones, benzyl benzoates, benzoin, α-acyloxamine esters, tetramethyl thiuram monosulfides, and thioxanthones Known radical generators such as may be used. In addition, since sulfonium salts and indonium salts, which are generally used as optical acid generators, operate as radical generators by irradiation of UV-rays, they may also be used alone in the invention. In addition, a photosensitizer may also be used in addition to the polymerization initiator for the purpose of improving the sensitivity. Examples of photosensitizers include n-butylamine, triethylamine, tri-n-butylphosphine, and thioxanthone derivatives.

The polymerization initiator may be used in combination, for example, when the curable resin generates only radicals and cations, one of them may be used alone. As the addition amount of the polymerization initiator, based on the total weight of the ethylenically unsaturated group-containing curable resin and the ring-opening polymerizer-containing curable resin contained in the curable composition, preferably within the range of 0.1 to 15% by weight, more preferably 1 It is used within the range of 10% by weight.

In the present invention, when using a crosslinkable polymer having a repeating unit represented by the structural formula (1) or a crosslinkable polymer having a repeating unit represented by the structural formula (3) (hereinafter collectively "polymer of the present invention" Because the polymers of the invention are generally solid or highly viscous liquids, they are difficult to be coated alone. If the polymer is water soluble or in an aqueous dispersion, it may be coated in an aqueous system, but is generally dissolved and coated in an organic solvent. As regards the organic solvent, those capable of dissolving the polymer of the present invention can be used without any particular limitation.

Preferred organic solvents include, for example, ketones such as methyl ethyl ketone, alcohols such as isopropanol, and esters such as ethyl acetate. In addition, when the curable resin having a monofunctional or multifunctional vinyl monomer or a monofunctional, bifunctional, trifunctional, or higher functional ring-opening polymerizable group is a low molecular weight curable resin, the viscosity of the curable composition can be adjusted using it together. And may be coated without using a solvent.

In addition, in the present invention, fine particles may be added to the curable composition. Since the amount of hardening reduction in the hard coating layer can be reduced by the addition of the fine particles, it is preferable that the adhesion close to the support can be improved or the curling can be reduced. As the fine particles, any of inorganic fine particles, organic fine particles and organic-inorganic hybrid fine particles can be used. The inorganic fine particles include, for example, silicon dioxide particles, titanium dioxide particles, zirconium oxide particles, and aluminum oxide particles. Such inorganic fine particles are generally hard, and when they are filled into the hard coating layer, not only can the reduction amount during curing be improved, but also the hardness on the surface can be improved.

However, since particulates generally tend to increase haze, filling security is controlled in terms of the balance of the respective desired properties.

In general, since the inorganic fine particles have a low affinity with organic components such as the polymer and multifunctional vinyl groups of the present invention, their simple mixing often tends to form agglomerates and cause cracking of the hard coating layer after curing. In the present invention, in order to increase the affinity between the inorganic fine particles and the organic component, the surface of the inorganic fine particles can be treated with a surface improving agent including organic pieces. The surface modifier preferably has a functional group capable of forming a bond with the fine inorganic particles and capable of absorbing the fine inorganic particles and a functional group having a high affinity with the organic component in one and the same molecule.

As an improving agent having a functional group capable of binding and absorbing inorganic fine particles, it has a surface improving agent of a metal alkoxide such as silane, aluminum, titanium, or zirconium and an anionic group such as a phosphate group, a sulfate group, a sulfonated base group, or a carboxylate. Surface modifiers are preferred.

In addition, as functional groups having high affinity with the organic component, those having hydrophobic or hydrophilic properties may be adopted to be controlled with the organic component. However, functional groups capable of chemically bonding with organic components are preferred, and ethylenically unsaturated groups or ring-opening polymerization groups are particularly preferred.

In the present invention, a preferred surface improving agent for the fine inorganic particles is a curable resin having a metal alkoxide or an anionic group and an ethylenically unsaturated group or a ring-opening polymerization group in the molecule.

Typical examples of surface improvers may include unsaturated double bond-containing binders, organic phosphate-containing organic curable resins, organic sulfate-containing organic curable resins, and organic carboxylate-containing curable resins.

S-1 H ₂ C = C (X) COOC ₃ H ₆ Si (OCH ₃ ) ₃ ,

S-2 H ₂ C = C (X) COOC ₂ H ₄ OTi (OC ₂ H ₅ ) ₃ ,

S-3 H ₂ C = C (X) COOC ₂ H ₄ OCOC ₅ H ₁₀ OPO (OH) ₂ ,

S-4 (H ₂ C = C (X) COOC ₂ H ₄ OCOC ₅ H ₁₀ O) ₂ POOH,

S-5 H ₂ C = C (X) COOH ₂ H ₄ OSO ₃ H,

S-6 H ₂ C = C (X) COO (C ₅ H ₁₀ COO) ₂ H,

S-7 H ₂ C = C (X) COOC ₅ H ₁₀ COOH,

S-8 3- (glycidyloxy group) propyltrimethoxysilane,

X represents a hydrogen atom or CH ₃ here.

Surface modification of the inorganic fine particles is preferably performed in the solvent. In addition, when the inorganic fine particles are mechanically finely dispersed, the surface improver is used together, or after the fine fine dispersion of the inorganic fine particles, the surface improver is added and stirred, or the surface modification is performed before finely dispersing the fine inorganic particles ( Thermal insulation, heating after drying or optionally performing PH change), and then fine dispersion may be used.

As a dissolving agent which melt | dissolves a surface improver, the organic solvent which has big polarity is preferable. Specific examples include known solvents such as alcohols, ketones, and esters.

There is no particular limitation on the organic fine particles, but ethylenically unsaturated groups such as, for example, polymethyl methacrylate, polyethyl methacrylate, polyethyl acrylate, polybutyl acrylate, polyethylene, polypropylene, and polystyrene Polymer particles containing monomers having monomers and polymer particles containing repeating units represented by Structural Formula (1) or (3) in the present invention are preferably used. Furthermore, it is polysiloxane, melamine resin, benzoguanamine resin, polytetrafluoroethylene, polycarbonate nilon, polyvinyl alcohol, polytetrafluoroethylene, polyethylene terephthalate, polyvinyl chloride, acetyl cellulose, nitrocellulose, And resin particles such as gelatin. It is preferred that such particles are crosslinked.

As a dispersing machine for pulverizing the fine particles, it is preferable to use, for example, ultrasonic waves, dispersers, homogenizers, dissolvers, polytrons, paint shakers, sand grinders, kneaders, age mills, dyno mills, coball mills and the like. Do.

The amount of the fine particles to be filled is preferably 2 to 40% by weight, more preferably 3 to 25% by weight and most preferably 5 to 15% by weight based on the volume of the hard coating layer after filling.

The haze of the hard coat layer of the present invention is preferably 7% or less, more preferably 5% or less, and most preferably 3% or less. In the haze evaluation method, a value automatically measured using a turbidity meter "NDH-1001DP" manufactured by Nippon Denshoku Co., Ltd .: haze = (diffuse light / total transmitted light) × 100 (%) was used.

In the hard coat film of the present invention, the value representing curl according to the following numerical formula B is preferably within the range of -15 to +15, more preferably within the range of -10 to +12, and -10 to +10 More preferred. In this case, the direction in which the curl is measured in the specimen depends on the direction of transport of the support when coated in a mesh shape.

Numerical formula B: curl = 1 / R

(R represents the radius of curvature m.)

This is an important property for not causing cracking or film peeling in the product, processing, and handling in the field of the hard coat film. It is preferable that the curl value is within the range described above and the curl is small. Reducing the curl to the above-described range and increasing the surface hardness can be achieved by adjusting the volume reduction amount of the curable composition for forming the hard coating layer to 15% or less.

Curls are measured using the curl measurement forming plate in Method A specified by "Curl Measurement Method for Photographic Films" according to JIS K 7619-1988. Measurement conditions are 25 ° C., 60% relative humidity, and moisture control time for 10 hours.

Plus to curl means curl with the coated side of the hard coat layer on the inside of the curve, while minus means curl with the coated side on the outside of the curve.

In addition, in the hard coating film of the present invention, based on the curl measurement method described above, when only relative humidity changes to 80% and 10%, the absolute value for the difference between the respective curl values is preferably 24 to 0. , 15 to 0 are more preferable, and 8 to 0 are the most preferable. This is a property related to handling, peeling, and cracking when the film is bonded under various humidity.

In the present invention, when the coated side of the hard coat layer is curved outward with respect to the crack resistance of the hard coat film, the radius of curvature causing the crack is preferably 50 mm or less, more preferably 40 mm or less, and 30 mm or less. Is more preferable. For cracks at the edges, it is preferable that there are no cracks or the length of the cracks is 1 mm or less on average. Crack resistance is an important property that does not cause crack bonding during handling such as coating, machining, cutting, and adhesion of hard coating films.

As for the support used for the hard-coat film of this invention, a transparent film, a sheet, or flat plastics is preferable. Specifically, the membrane or sheet can be, for example, polyester such as polyethylene terephthalate and polyethylene naphthalate, cellulose such as triacetyl cellulose and diacetyl cellulose, polycarbonate, polymethyl methacrylate, polycarbonate, polysulfone, Preference is given to polyether sulfone polyallylates, cycloolepicin polymers. 20-300 micrometers is preferable and, as for the thickness of a film | membrane, 80-200 micrometers is more preferable. If the thickness of the substrate is too thin, the strength of the film is weak, while if the thickness is thick, the strength is too large. The thickness of the sheet may be within a range that does not deteriorate transparency, and those having a few millimeters at 300 μm or more may be used.

The active energy photocurable coating solution (coating dissolving agent of the curable composition) is prepared mainly by dissolving the above-mentioned heavy parasitic monomer and polymerization initiator in an organic solvent such as a ketone, an alcohol, or an ester. In addition, solution dispersion of fine inorganic particles with a hard surface modified and solution dispersion of soft fine particles may be added for preparation.

The hard coating layer of the present invention is a known thin film formation such as dipping method, spinner method, spray method, roll coating method, grabber method, wire bar method, slot extrusion coating method (single or multi-layer), or slide coating method It can be prepared by coating the active energy photocurable coating solubilizer on the substrate by the method, and irradiating the active energy light to dry and harden the coated material.

After drying, drying is carried out under conditions in which the concentration of the organic solvent in the coated solution membrane is preferably at most 5% by weight, more preferably at most 2% by weight, even more preferably at most 1% by weight. Drying conditions are affected by thermal strength, rate of transport to the substrate, and length of drying step. Low content organic solvents are desirable to increase the rate of polymerization.

In addition, for the purpose of improving the dense adhesion of the substrate and the hard coating layer, the surface treatment may optionally be applied on the inside or both sides of the surface of the substrate by the oxidation method and the roughening method. Examples of the oxidation method may include a corona discharge method, an incandescent discharge method, a chromic acid treatment (wet), a flamming method, a hot blow treatment, and an ozone / UV-light irradiation treatment.

In addition, one or more undercoat layers may be provided. The material of the undercoat layer comprises, for example, vinyl chloride, vinylidene chloride, latex or copolymer of butadiene, (meth) acrylate or vinyl ester, ester or low molecular weight polyester, gelatin, gelatin. In addition, the undercoat layer may be mixed with an antioxidant, for example, a tin oxide, a mixed oxide of tin oxide / antimony oxide, a mixed oxide of tin oxide / indium oxide, and a metal oxide such as a quaternary ammonium salt.

The hard coat layer may be composed of a plurality of layers, and may be manufactured by appropriately stacking the layers in the order of hardness.

The light transmitting layer of the present invention is preferably bonded with a pressure-sensitive adhesive layer having a substrate including a support or a recording layer. In the step of providing the pressure-sensitive adhesive layer, the pressure-sensitive adhesive layer may be formed after the light transmitting film having the hard coating layer previously formed on the surface and the hard coating layer coated on the surface. The method for providing a pressure-sensitive adhesive layer is generally a method of adhering a previously formed pressure-sensitive adhesive layer (hereinafter sometimes referred to as an indirect method) and a method of directly coating a pressure-sensitive adhesive on the surface of the light transmitting film and drying to form a pressure-sensitive adhesive layer. (Hereinafter sometimes referred to as direct method).

In the indirect method, the "method of a previously formed pressure-sensitive adhesive layer" means that, for example, a pressure-sensitive adhesive is subsequently coated on the surface of the emitting film having the same size as the light transmitting film, and the adhesive is dried to cover the entire area of one surface of the emitting film. It is a method of providing a pressure-sensitive adhesive layer and adhering the pressure-sensitive adhesive layer to the light transmitting film. As a result, a pressure-sensitive adhesive layer having a release film is provided in all regions on the other surface of the light transmitting film.

The direct method transmits the upper end of the rolled up light transmitting film to a predetermined coating area, and then coats the pressure sensitive adhesive from the upper end to the last end on one surface of the light transmitting film to form a coating film, and then continuously The coating film is dried to provide a pressure-sensitive adhesive layer over the entire area on the other surface of the light transmitting film.

In direct and indirect methods, known coating means can be used as coating means for pressure sensitive adhesives. Specifically, it includes, for example, spray roll coating, blade coating, doctor roll coating, and screen printing.

In addition, as the drying means, known means such as thermal drying and wind drying can be used.

As the pressure sensitive adhesive, an acrylic, rubber or silicone adhesive can be used, while a pressure sensitive acrylic adhesive is preferred in view of transparency and durability. As such an acrylic pressure sensitive adhesive, 2-ethylhexyl acrylic as the main component, for example with short chain alkyl acrylates or methacrylates such as methyl acrylate, ethyl acrylate or methyl methacrylate, in order to improve the bonding force It is preferable to use a copolymerized product containing a rate or n-butyl acrylate, and acrylic acid, methacrylic acid, acrylamide derivative, maleic acid, hydroxyethyl acrylate, or glycidyl acrylate may be used as a crosslinking agent. It may be a crosslinkable point. The glass transition temperature (Tg) and the crosslinking concentration can be varied by controlling the mixing ratio and the nature of adjusting the kind of the main component, the short chain and the component for addition of the crosslinking point.

Examples of the crosslinking agent used in bonding with the adhesive include an isocyanate crosslinking agent, an epoxy resin crosslinking agent, a melamine resin crosslinking agent, a urea resin crosslinking agent, and a chelate crosslinking agent, among which an isocyanate crosslinking agent is preferable. As such isocyanate crosslinking agent, tolylene diisocyanate, 4-4'-diphenylmethane diisocyanate, hexamethylene diisocyanate, silylene diisocyanate, naphthylene-1,5-diisocyanate, o-toluidine isocyanate, Isocyanates, such as isophorone diisocyanate, and triphenylmethane triisocyanate, reaction products of such isocyanates and polyalcohols, or polyisocyanates resulting from condensation of isocyanates can be used. Examples of commercially available products of such isocyanates are, for example, Coronate L, Coronate HL, Coronate 2030, Coronate 2031, manufactured by Nippon Polyurethane Industry Co. Ltd. Myrionate MR, myrionate HTL; Takenate D-102, Takenate D-110N, Takenate D-200, Takenate D-202, manufactured by Takeda Pharmaceutical Co. Ltd .; Death module L, death module IL, death module N, and death module HL, manufactured by Sumitomo Bayer Co. Ltd.

The pressure-sensitive adhesive layer is formed of a light transmitting film on the surface rather than the surface provided with the hard coating layer, and the emission film is formed on the surface of the pressure-sensitive adhesive layer to prevent close adhesion between the coating layer and the pressure-sensitive adhesive layer when the film is rolled up in a roll shape in a subsequent step. It is preferable to adhere to. As described above, in an indirect method, the release film may be in a previously bonded state. On the other hand, in the indirect method, it is preferable to add the step of adhering the emitting film to the surface of the pressure-sensitive adhesive layer after forming the pressure-sensitive adhesive layer on the surface of the light transmitting film. The release film adhered to the surface of the pressure-sensitive adhesive layer includes a polyethylene film, a polyethylene terephthalate film, a polyethylene naphthalate film, a polycarbonate film, and a triacetate cellulose film.

The thickness of the light transmitting layer of the recording medium according to the present invention is preferably smaller than the thickness of the support. In view of the increase in deformation when the recording medium is tilted, the thickness is preferably 50 to 300 m, more preferably 60 to 200 m, and still more preferably 70 to 120 m. In addition, the change in thickness at one surface is at most ± 3 μm, preferably at most ± 2 μm. More preferably, it is ± 1 micrometer or less.

The optical recording medium of the present invention performs recording and reproduction of information, for example, as described below. First, while the optical recording medium is rotated at a predetermined linear velocity (0.5 to 10 m / sec) and a predetermined constant angular velocity, at the recording light such as blue violet laser light, for example, at the wavelength of 405 nm, the side of the light transmitting layer Is irradiated from the via lens. In response to light irradiation, the recording layer absorbs light so that the temperature locally increases, for example, holes are created to change its optical properties and record information. The information recorded as described above is reproduced by using a blue-violet laser as the optical means and detecting the light reflection therefrom while the optical recording medium rotates at a predetermined constant linear velocity and irradiates laser light on the side of the light transmitting layer. Can be.

Laser light sources having a vibration wavelength of 500 nm or less as optical means for recording and reproduction include, for example, a blue violet semiconductor laser having a vibration wavelength within a range of 390 to 415 nm and a blue violet laser SHG having a central vibration wavelength of 425 nm. It includes a laser.

In addition, in order to increase the recording density, the NA of the objective lens used for pick-up is preferably 0.7 or more, and more preferably 0.85 or more.

 Example

Although the present invention will be described in more detail below, the present invention is not limited to the embodiments described below.

Preparation of Optical Recording Media

A. Preparation of substrate and recording layer

Extruded polycarbonate resin and 1.1 mm thick, 120 mm diameter polycarbonate (Teijin Chemical) with silver having a helical groove (100 nm deep, 120 nm wide, and 320 nm track pitch) Sputtered on the grooved surface of Panrite AD 5503, manufactured by, to form a 100 nm thick light reflection layer.

Then, 20 g of orazole blue GN (recording material 1: phthalocyanine dye, manufactured by Ciba Specialty Chemicals) was added to 1 liter of 2,2,3,3-tetrafluoropropanol, and the sonication dissolved it. It was applied for 2 hours to prepare a coating dissolving agent to form a recording layer. The prepared coating solvent was coated on the light reflection layer under 23 ° C. and 50% RH conditions while the rotation speed was varied up to 300 to 4000 rpm. The recording layer formed after storage at 23 ° C. and 50% RH for 1 to 4 hours had a thickness of 100 nm. ZnS-SiO ₂ was sputtered on the recording layer so as to have a thickness of 5 nm, thereby forming an intermediate layer (barrier layer).

In addition, as another example of the recording material, in place of orazole blue GN, a laminated film containing AgPdCu / ZnSSiO / AgInSeTe / ZnSSiO (recording material 2) is deposited as a phase change recording layer using a DC and RF sputtering method. Was formed by. Each use of the recording materials 1 and 2 is described in Table 4.

B. Preparation of the light transmitting layer (hard coating film)

The light transmitting layer (hard coating film) provided on the recording layer includes a pressure-sensitive adhesive layer, a light transmitting film, a hard coating layer, and an optional antifouling layer thereon in this order from the side of the substrate. In this case, an embodiment of the preparation of a light transmitting layer comprising a pressure-sensitive adhesive layer, a light transmitting film, a hard coating layer, and an optional antifouling layer is shown, and a method for preparing a light transmitting film (cellulose acylate film or cycloolefin film) is shown. The coating of the hard coating layer, and the coating of the antifouling layer will be described below in this order.

1-1. Preparation of Cellulose Acylate Film (TAC-1)

Dihydrides having an average molecular weight of 2125 or less comprising ethylene glycol and tolylene diisocyanate (TDI) having repeating units of adipic acid and-[O- (CH ₂ ) ₂ -OCO- (CH ₂ ) ₄ CO]- The hydroxyl terminated polyester was treated to synthesize a methyl chloride soluble polyester urethane resin having an average molecular weight of 7300. The compound is called PU-1. Cellulose acetate was added to PU-1 to obtain dope of the composition described below.

100 parts by weight of cellulose triacetate

(Degree of substitution: 2.85, substitution degree of 6-position: 0.90)

PU-1 15 parts by weight

270 parts by weight of methylene chloride

Butanol 7 parts by weight

10 parts by weight of methanol

The composition was filled into a tightly sealed container and bent under pressure while completely maintained at a temperature of 80 ° C to dissolve completely. The dope was then filtered, cooled and cast while kept at 25 ° C. on a 30 cm diameter circulating drum with a lid. The drum consists of Sb material plated with a Ni layer of approximately 50 μm and further has two hard chromium platings of approximately 40 μm each, and the surface affects the highest mirror polishing at 0.01 to 0.05 S. In this case, the surface temperature of the drum was maintained at 0 ° C. by passing cold water through the lid. The casting speed was fixed at 3 m / min, the membrane was peeled by a peeling roll at a position 270 ° rotated in the casting direction from the casting position, the base was raised at a speed of 3.15 m / min, and 5% casting was in the casting direction. Was performed. The filled base was fixed on both sides and dried by hot wind at 70 ° C. to obtain an 80 μm thick membrane. When the humidity changed, the moisture absorption coefficient determined by measuring the length of the membrane was 70 ppm /% RH.

1-2. Preparation of Cellulose Acylate Membrane (TAC-2,3,4,5,6,7) Containing Degradation Agent

TAC-2 (addition of deterioration inhibitor 1), TAC-3 (addition of deterioration inhibitor 2), TAC-4 (addition of deterioration inhibitor 3) with a film thickness of 80 µm. TAC-5 (addition of degradation inhibitor 4) and TAC-6 (addition of degradation inhibitor 5) are the same as in 1-1 except that each of the degradation inhibitors 1 to 5 described below is doped with TAC-1 by 1 part by weight. It was prepared in the same way. Each membrane has a coefficient of hygroscopic expansion of 60, 43, 30, 25 and 35 ppm /% RH.

 1-3. Preparation of the cellulose acylate film (TAC-8) containing an organic chlorine-containing solvent in a composition of 10 ppm or less

(Composition of dope in surface layer)

100 parts by weight of cellulose acetate

(Degree of substitution: 2.9, substitution degree at the 6-position: 0.90)

Triphenyl phosphate 13 parts by weight

0.5 parts by weight of tribenzylamine

314 parts by weight of methylene chloride

44 parts by weight of methanol

12 parts by weight of n-butanol

(The composition of the dope in the core layer)

100 parts by weight of cellulose acetate

(Degree of substitution: 2.5, substitution degree in 6-position: 0.80)

10 parts by weight of triphenyl phosphate

5 parts by weight of diethyl phthalate

0.5 parts by weight of tribenzylamine

Acetone 256 parts by weight

110 parts by weight of methanol

The dope solubilizers, each having the composition described above, were formed on the support by co-casting on both the front and back sides of a 74 μm core layer so that the outer layer (top and bottom surface layers) were each 3 μm thick with a dried film. After filtration and cast on, it was prepared by a known method. In co-casting, each dope was cast on a stainless steel substrate using a feed-block type dye under 35 ° C. The cast product was dried and peeled at 80 ° C. for 3 minutes and further dried at 120 ° C. for 10 minutes to obtain a dried membrane sample. The composition of the chlorine solvent measured by gas chromatography was 4 to 8 ppm. The moisture absorption expansion coefficient of the membrane was 40 ppm /% RH.

1-4. Preparation of cellulose acylate membrane (TAC-9,10,11) comprising polyhydric alcohol ester of aliphatic polyhydric alcohol and at least one monocarboxylic acid

Cellulose triacetate (Linter, acetylation degree: 62.0%) 160 kg

40 kg of dipropylene glymol dibenzoate

Methylene chloride 770 kg

65 kg of ethanol

The material described above was filled into a tightly sealed container, flexed and dissolved to prepare a dope solvent. The dope solubilizer was then cast uniformly on a stainless steel band substrate 1500 mm wide at 33 ° C. using a belt casting device. The temperature of the stainless steel bands was controlled at 25 ° C. The solvent was evaporated until the amount of residual solvent in the film cast on the stainless steel band substrate was reduced by 25%. The membrane was then peeled from a stainless steel band at a peeling tension of 127 N / m. The filled cellulose triacetate membrane was dried while being transported by a number of rolls in the drying zone to obtain a TAC-9 specimen of cellulose triacylate membrane of 80 μm thickness.

TAC-10 was prepared in the same manner as described above, except replacing polyhydric alcohol with compound 16 in dipropylene glycol dibenzoate. In addition, TAC-11 was added in the same manner as in TAC-10, except that 0.8 g of TINUVIN 109, 171, and 326 (benzotriazole UV-light absorbers manufactured by Ciba Specialty Chemicals) were each added. Ready

1-5. Preparation of Cycloolefin Membrane (ZEO)

The cycloolefin resin prepared by hydrogenating the ring-opening copolymer of dicyclopentadiene-tetracyclododecene (glass transition temperature: 98 ° C., 5% heat loss temperature: 360 ° C.) was melted while heating in kneader at 180 ° C. to melt Obtained. Using an 8 inch 4 inverted L type calendering machine, the molten resin passed through the gaps between the rolls continuously while each roll was installed at a temperature of 190 ° C. and finally peeled off and cooled to 80 A microporous cyclopolyolefin membrane was obtained. The moisture absorption coefficient of the film was 9 ppm /% RH.

2. Formation of Hard Coating Layer

2-1. Preparation of Coating Solvents for Hard Coating Layers

(1) Preparation of H-1 Solvent

Glycidyl methacrylate was dissolved in methyl ethyl ketone (MEK), and the reaction was carried out at 80 ° C. for 2 hours while a thermal polymerization initiator (V-65 manufactured by Wako Pure Chemical Co., Ltd.) was added dropwise. The obtained half was dissolved in hexane and the precipitate was dried under reduced pressure to give polyglycidyl methacrylate (molecular weight: 12,000, converted to polystyrene), which was methyl to obtain 50% by weight concentration. Dissolved in ethyl ketone. 150 parts by weight of trimethylol propane triacrylate (biscote # 295; manufactured by Osaka Yuki Kagaku Koyosa), and 6 parts by weight of optical radical polymerization initiator (by Shiba Zeigisa) Produced, Illucure 184), 6 parts by weight of the optically anionic polymerization initiator (Rodzyl 2074, manufactured by Roadia), and 10 parts by weight of Megafax 531A (made by Dainippon Ink and Chemicals, Inc.). ) Was mixed while flexing and dissolved in 30 parts by weight of methyl isobutyl ketone to prepare a coating solvent (H-1) for the hard coating layer.

(2) Preparation of H-2 Solvent

The coating solvent (H-2) for the hard coating layer is the same as that prepared in the coating solvent (H-1), except that Megapack 531A is replaced with X-22-164B (manufactured by Sinechu Chemical Co., Ltd.) of the same weight. Prepared in a way.

(3) Preparation of H-3 Solvent

Of 93 parts by weight of dipentaerythritol hexaacrylate (DPHA, manufactured by Daicel UCB), 5 parts by weight of R-3833 (made by Daikin Fine Chemical Institute), of X-22-164C 2 parts by weight (manufactured by Sinechu Chemical Co., Ltd.), 3 parts by weight of optical radical polymerization initiator (Ilugacure 907), which was prepared by Zeji Inc., and methyl ethyl ketone / methyl isobutyl ketone (1: 1 weight ratio), and dissolved in a solution mixture to prepare a coating solvent (H-3) for a hard coat layer.

(4) Preparation of H-4 Solvent

The coating solvent for hard coat layer (H-4) was prepared in the same manner as in the preparation of the coating solvent for hard coat layer (H-1) except that MegaFax 531A was not added.

(5) Preparation of H-5 Solvent

Coating dissolving agent for hard coating (H-5) is a coating dissolving agent for hard coating layer except for replacing Megapack 531A with a heat-crosslinkable fluorine-containing polymer (JN-7214, manufactured by JSR) of the same weight ( It was prepared in the same manner as in the preparation of H-1).

(6) Preparation of H-6 Soluble

The solvent for the hard coat layer (H-6) was prepared in the same manner as in the preparation of the coating solvent for the hard coat layer (H-3) except that R-3833 was added.

(7) Preparation of Coating Solvent (a-1) for Antifouling Agent

Isopropyl alcohol was added to the thermal crosslinkable chlorine containing polymer (JN-7214, manufactured by JSR) to prepare 0.2% by weight of coarse solution dispersion. The coarse solution dispersion was dispersed at supersonic speed to prepare a coating solvent to prevent contamination.

2-2. Preparation of Hard Coating Film (Coating of Hard Coating Layer)

(1) Preparation of Single Layer Hard Coating Film

Corona treatment was applied to both surfaces of the cellulose acylate film and cyclopolyolefin formed to an 80 μm film thickness, and includes a styrene butadiene copolymer having a 1.55 refractive index and a glass transition temperature of 37 ° C. (manufactured by Nippon Xeon Co., Ltd.). , LX407C5) and tin oxide / antimony oxide hybrid oxide (FS-10D, manufactured by Inshihara Sangyo Co., Ltd.) were mixed at a weight ratio of 5.5 and coated with a dry film thickness of 200 nm on the surface formed of the hard coating layer to form a non-fixed layer. An undercoating layer was formed, and then the coating solvent for hard coating described above was coated by the extrusion method, dried to each thickness described in Table 4, UV-rayed (700 mJ / cm ² ) and the hard coat film of each thickness described in Table 4 were prepared, and it was wound up in each roll shape.

In addition, a polycarbonate film (PC) was used as the light transmitting film, and a hard coating layer was formed on the film as described below. A rolled carbonate film (Teigin Pure Ace: 75 μm thick with a release film on one side and a moisture absorption expansion coefficient of 12 ppm /% RH) was used and sent to the desired coating area. After removing the previously provided emission film, the hard coating solvent was coated to form a coating layer, and irradiation light was continuously irradiated onto the coating layer to cure the irradiation and curable resin (UV-ray curable resin) to form a hard coating layer.

(2) Formation of Hard Coating Film Having Contamination Prevention Layer

For the hard coat film used for the optical recording medium shown in Table 4, after coating the hard coat layer (H-4), the coating solvent for antifouling layer (a-1) was dried with a thickness of 0.1 μm using a wire bar. Was coated and dried, and thermally cured to form an antifouling layer to obtain a hard coat film having an antifouling layer.

C. Adhesion between Hard Coating Film and Substrate

An optical recording medium was prepared as described below by adhering the hard coating film prepared in B to the recording layer provided in the support described in A.

1. Preparation of Pressure Sensitive Adhesive

Acrylic copolymer (solvent: ethyl acetate / toluene = 1/1) and isocyanate crosslinker (solvent: ethyl acetate / toluene = 1/1) were mixed at 100: 1 (weight ratio) to prepare pressure sensitive adhesive coating solvent A. . Using the pressure-sensitive adhesive coating solvent A, a pressure-sensitive adhesive layer is provided on the surface of the release film in an indirect manner.

While transporting the polystyrene release membrane wound around the roll, the pressure sensitive adhesive coating solvent A was coated onto the surface of the release membrane with a dry thickness of 20 μm. Subsequently, it dried at 100 degreeC in the dry area, and obtained the release film | membrane with a pressure-sensitive adhesive tape.

2. Preparation of Transparent Sheet for Optical Recording Media

The release film provided with the pressure-sensitive adhesive layer was adhered to the hard coat film on the surface opposite to the surface provided with the hard coat layer in which the pressure-sensitive adhesive layer was in contact with the film. Then, the hard coat film and the pressure-sensitive adhesive layer with the hard coat layer were wound around the roll shape again, and maintained in this state in an atmosphere of 23 ° C. and 50% RH.

Then, the hard coat film and the pressure-sensitive adhesive layer with the hard coat layer were rolled and knocked in the same shape as the substrate. Thus, a transparent sheet for an optical recording medium having a pressure-sensitive adhesive layer on one surface and a hard coating layer on the other surface of the light transmitting film was obtained.

3. Preparation of the optical recording medium (adhesion of the hard coating film to the support and the recording layer)

The release film on the side of the pressure-sensitive adhesive tape was peeled from the transparent sheet for the disc-shaped recording medium, and the intermediate layer and the pressure-sensitive adhesive layer were attached to each other by roller compression means to prepare an optical recording medium.

D. Preparation of the light transmitting layer by spin coating

As a comparative example, an optical recording medium having a light transmitting layer prepared by the method described below was prepared instead of the light transmitting layers by B and C.

After sputtering ZnS-SiO ₃ to the recording layer to form a light transmitting layer having a thickness of 90 nm, UV-curable resin (trade name, SD-661, manufactured by Dainippon Ink and Chemicals Co., Ltd.) was rotated at 100 rpm. The light transmitting layer was coated by spin coating while varying from to 300 rpm, and UV-rays were irradiated with a UV lamp to cure the resin coating above to prepare an optical recording medium.

E. Measurement

1. Pencil hardness test

After adjusting the humidity under a temperature of 25 ° C. and a relative humidity of 60% for 2 hours with respect to the film of the light transmitting layer for the recording medium, the pencil hardness of which no defects were observed under a load of 9.8 N was JIS-K-5400. It was determined using a test pencil according to JIS-S-6006 consistent with the pencil hardness evaluation method according to FIG.

2. scratch resistance

When rubbing the surface of the recording medium on the side of the light transmitting layer under a load of 1.96 N / cm 2 using a # 0000 steel wool, a measure of the degree of scratching of the scratches (“A” was rubbed for 300 cycles, then no traces were seen) "B" shows traces slightly, "C" shows traces but no traces up to 100 cycles, and "D" shows traces within 100 cycles).

3. Pollution Prevention Properties

Dry oil ink (" MAKKY " manufactured by Zebra Co., (registered trade name)) described on the surface of the light transmissive layer side merchant recording medium was transferred to Toray Co. Assessment of the condition after several rapid wipes using (registered trade name) "TRACY" manufactured by (registered trade name) "A" indicates that the traces described are completely wiped, and "B" shows near wipe But a little left, "C" is partially left without wiping the described trace, and "D" is left without most wiping)

4. Measurement of recording characteristics

The recording medium described above was installed in a recording / reproducing apparatus having a pick-up composed of a blue-violet laser emitting light at λ = 405 nm and an objective lens having an oral ratio of 0.7 NA, and set at the shortest pit length of 0.24 μm. The corrected signal D8-14 was recorded and reproduced to measure signal regeneration jitter. Smaller jitter is more preferable, and 5% or less is particularly preferable. For the jitter increase in Table 4, the signal regeneration jitter was measured in the same way, stored under 80 ° C., 80% RH conditions for 7 days, with the jitter increase representing the difference between the jitter values before and after storage.

Thus, the prepared optical recording medium and various measurement results therefor are shown in Table 4.

In Table 4, in the optical recording media 6 to 15 formed by adhering the hard coat films each having the hard coat layer of the present invention to TAC-2 to TAC-11, the following are found: pencil hardness, scratch resistance, and contamination In addition to improving the protection properties, the jitter increase was reduced to improve the recording characteristics. In the optical recording medium 5 formed by adhering the hard coating layer with the hard coating layer of the present invention to a general cellulose acylate film (TAC-1), only pencil hardness, scratch resistance, and antifouling property were improved, while contamination The recording characteristics of the optical recording media 6 to 11 using a cellulose acylate film having a moisture absorption coefficient of 8 ppm /% RH to 62 ppm /% RH, mixed with an inhibitor or reduced in composition of the organic chlorine solvent to 10 ppm or less, were observed. It was an improvement, which was an unexpected effect. In addition, the optical recording medium formed by adhering the hard coat film having the hard coat layer of the present invention to the cycloolefin film and the polycarbonate film has been improved in pencil hardness, scratch resistance, and antifouling properties, thereby achieving desired performance.

This application is based on Japanese Patent Application Nos. 2003-324185 and 2003-389263, filed September 17, 2003 and November 19, 2003, respectively, the contents of which are hereby incorporated by reference. .

Industrial availability

The present invention is applicable to optical recording systems, and is particularly effective for optical recording systems using blue violet lasers and high NA pick-ups.

Claims (13)

A recording medium capable of reproducing an information signal by optical means, support fixture; A recording layer capable of recording the information signal; And a light transmitting layer capable of transmitting light sequentially. The light transmitting layer comprises a light transmitting film having a moisture absorption expansion coefficient of 8 ppm /% RH to 62 ppm /% RH; And the light transmitting layer has a surface having a pencil hardness of 2H or higher. The method of claim 1, The light transmitting layer includes a hard coating layer on the light transmitting film, The hard coat layer, the first curable resin having a molecule having two or more ethylenically unsaturated groups; And a cured film formed from a curable composition comprising a second curable resin having a ring-opening polymerizer. The method of claim 2, And the light transmitting film is a cyclic polyolefin film.  The method of claim 2, And the light transmitting film is a polycarbonate film. A recording medium capable of reproducing an information signal by optical means, support fixture; A recording layer capable of recording the information signal; And a light transmitting layer capable of transmitting light sequentially. The light-transmitting layer comprises a cellulose acyl comprising at least one deterioration inhibitor selected from the group consisting of (A) a peroxide-decomposing agent, (B) a radical chain inhibitor, (C) a metal-inactive agent, and (D) an acid trapping agent. A recording medium comprising a light transmitting film including a late film. A recording medium capable of reproducing an information signal by optical means, support fixture; A recording layer capable of recording the information signal; And a light transmitting layer capable of transmitting light sequentially. And the light transmitting layer comprises a light transmitting film comprising a cellulose acylate film having an organic chlorine-containing solvent of 10 ppm or less. A recording medium capable of reproducing an information signal by optical means, support fixture; A recording layer capable of recording the information signal; And a light transmitting layer capable of transmitting light sequentially. And the light transmitting layer comprises a light transmitting film comprising a cellulose acylate film comprising a polyhydric alcohol ester of an aliphatic polyhydric alcohol and a monocarboxylic acid. The method of claim 7, wherein Wherein said monocarboxylic acid has an aromatic ring or a cycloalkyl ring. The method according to claim 7 or 8, Wherein said aliphatic polyhydric alcohol is one of a divalent to 20-valent alcohol. The method according to any one of claims 5 to 9, The light transmitting film has a hygroscopic expansion coefficient of 8 ppm /% RH to 62 ppm /% RH. The method according to any one of claims 5 to 10, The light transmitting layer comprises a hard coating layer on the light transmitting film; Wherein said hard coat layer comprises a cured film formed from a curable composition, said curable composition comprising a curable resin that can be cured with active energy light. The method of claim 11, The curable composition includes a first curable resin having a molecule having two or more ethylenically unsaturated groups; And a second curable resin having a ring-opening polymerizer. The method according to any one of claims 1 to 12, And the light transmitting layer has a thickness of 50 µm to 300 µm.