CN102532850A - Method for making makrolon serial resin film for optics and makrolon serial resin film for optics - Google Patents

Abstract

Provided is a method for making Makrolon serial resin film for optics which is capable of inhibiting fuming amid forming process. The method comprises the step of extruding Makrolon series resin composite in a melt manner and is characterized in that: corresponding to 100 parts of Makrolon series resin by weight, the Makrolon series resin composite comprises less than 0.05 parts of the release agent by weight.

Description

Method for producing polycarbonate-based resin film for optics, and polycarbonate-based resin film for optics

technical field

This invention relates to the manufacturing method of the polycarbonate-type resin film for optics. Furthermore, this invention relates to the polycarbonate-type resin film for optics obtained by this manufacturing method. the

Background technique

Optical films such as light guide films, retardation films, light diffusion films, and protective films for polarized light separators are required to have excellent transparency, heat resistance, and the like. Films made of polycarbonate-based resins are excellent in transparency, heat resistance, impact resistance, and rigidity, and thus are useful as optical films. the

Patent Document 1 discloses a polycarbonate-based resin composition containing a mold release agent and a thermal stabilizer, and discloses that a molded article obtained by injection molding the resin composition has excellent moldability (release property). the

Patent Document 1: JP2008-274007A

Contents of the invention

However, when the release agent-containing polycarbonate resin composition described in Patent Document 1 is melt-extruded to form a film, fumes may be generated. the

Therefore, the subject of this invention is providing the manufacturing method of the polycarbonate-type resin film for optics which can suppress the fuming at the time of molding. Moreover, the polycarbonate-type resin film for optics obtained by this manufacturing method is provided. the

The inventors of the present invention have made intensive studies in order to solve the above-mentioned problems, and as a result, have found a solution including the following configurations. the

(1) A method for producing a polycarbonate-based resin film for optics, comprising melt-extruding a polycarbonate-based resin composition, characterized in that, with respect to 100 parts by weight of the polycarbonate-based resin, the polycarbonate-based resin is combined The product contains less than 0.05 parts by weight of release agent. the

(2) The method for producing an optical polycarbonate-based resin film according to (1) above, wherein the release agent is an ester of an alcohol and a fatty acid. the

(3) The method for producing an optical polycarbonate-based resin film according to (2) above, wherein the release agent is an ester of a polyhydric alcohol and a fatty acid. the

(4) The method for producing an optical polycarbonate-based resin film according to (3) above, wherein the release agent is a partial ester of a polyhydric alcohol and a fatty acid. the

(5) The method for producing an optical polycarbonate-based resin film according to any one of the above (1) to (4), wherein the thickness of the optical polycarbonate-based resin film is 30 to 300 nm, and the total light rays The transmittance is above 85%. the

(6) The method for producing an optical polycarbonate-based resin film according to any one of (1) to (5) above, wherein the optical polycarbonate-based resin film has a haze of 50% or more. the

(7) The method for producing an optical polycarbonate-based resin film according to any one of (1) to (6) above, wherein the optical polycarbonate-based resin film has a surface gloss of 50% or less. the

(8) The method for producing an optical polycarbonate-based resin film according to any one of (1) to (7) above, wherein when the wavelength of incident light is 590 nm, the optical polycarbonate-based resin film The retardation of the resin film was 30 nm or less. the

(9) The method for producing an optical polycarbonate-based resin film according to any one of (1) to (8), wherein at least one surface of the optical polycarbonate-based resin film is a matte surface. the

(10) The method for producing an optical polycarbonate-based resin film according to (9) above, which includes forming a mat surface using a mat roller. the

(11) An optical polycarbonate-based resin film obtained by the production method described in any one of (1) to (10) above. the

(12) The optical polycarbonate-based resin film according to the above (11), which is used for a liquid crystal display device. the

(13) The polycarbonate-based resin film for optics as described in (12) above, which is used to protect the polarized light separator in the liquid crystal display device. the

According to the present invention, it is possible to provide a method for producing a polycarbonate-based resin film for optics, which can suppress (or reduce) smoke generation during film molding. Moreover, the polycarbonate-type resin film for optics obtained by this manufacturing method can be provided. the

Description of drawings

FIG. 1 is a schematic diagram illustrating an example of a production process of the polycarbonate-based resin film for optics of the present invention. the

2 is a schematic diagram illustrating an example of using the optical polycarbonate resin film of the present invention as a protective film for a polarized light separator of a liquid crystal display device. the

FIG. 3 is a schematic view showing the position of a suction probe (suction probe) for measuring the number of evaporatives generated from the outlet of the die 3. FIG. the

Symbol Description

1 melt extruder

2 polymer filter

3 die head

4 1st cooling roll

5 2nd cooling roller

6 3rd cooling roller

7 Polycarbonate-based resin films for optics

8 backlight unit

9 polarized light separator

10 Protective film for polarized light separator

11 LCD panel

Detailed ways

Next, the present invention will be described in detail. The manufacturing method of the polycarbonate-type resin film for optics of this invention comprises melt-extruding the polycarbonate-type resin composition containing a predetermined amount or less of a mold release agent. Thereby, smoke generation can be suppressed, and the polycarbonate-type resin film for optics can be manufactured. the

<Polycarbonate resin composition>

The polycarbonate-based resin composition contains a polycarbonate-based resin and contains a release agent in a predetermined amount or less (it may not contain a release agent in some cases). the

The polycarbonate-based resin is not particularly limited as long as it is a resin that is generally recognized as a polycarbonate-based resin, and is a resin that can manufacture the target resin film of the present invention. For example, heat resistance, mechanical strength, and transparency can be preferably used. Aromatic polycarbonate resin with excellent properties. the

Aromatic polycarbonate resins generally include resins obtained by reacting dihydric phenols with carbonate precursors by interfacial polycondensation or melt transesterification, and resins obtained by polymerizing carbonate prepolymers by solid-phase transesterification. , and resins polymerized by ring-opening polymerization of cyclic carbonate compounds, and the like. the

The above-mentioned dihydric phenol is not particularly limited as long as it is a compound recognized as a dihydric phenol, and is a dihydric phenol that can be used to manufacture polycarbonate-based resins and can manufacture the target resin film of the present invention. For example, : Hydroquinone, resorcinol, 4,4'-dihydroxybiphenyl, bis(4-hydroxyphenyl)methane, bis{(4-hydroxy-3,5-dimethyl)phenyl}methane, 1 , 1-bis(4-hydroxyphenyl)ethane, 1,1-bis(4-hydroxyphenyl)-1-phenylethane, 2,2-bis(4-hydroxyphenyl)propane (commonly known as bis Phenol A), 2,2-bis{(4-hydroxy-3-methyl)phenyl}propane, 2,2-bis{(4-hydroxy-3,5-dimethyl)phenyl}propane, 2 , 2-bis{(4-hydroxy-3,5-dibromo)phenyl}propane, 2,2-bis{(3-isopropyl-4-hydroxy)phenyl}propane, 2,2-bis{ (4-Hydroxy-3-phenyl)phenyl}propane, 2,2-bis(4-hydroxyphenyl)butane, 2,2-bis(4-hydroxyphenyl)-3-methylbutane, 2,2-bis(4-hydroxyphenyl)-3,3-dimethylbutane, 2,4-bis(4-hydroxyphenyl)-2-methylbutane, 2,2-bis(4 -Hydroxyphenyl) pentane, 2,2-bis(4-hydroxyphenyl)-4-methylpentane, 1,1-bis(4-hydroxyphenyl)cyclohexane, 1,1-bis( 4-hydroxyphenyl)-4-isopropylcyclohexane, 1,1-bis(4-hydroxyphenyl)-3,3,5-trimethylcyclohexane, 9,9-bis(4- hydroxyphenyl)fluorene, 9,9-bis{(4-hydroxy-3-methyl)phenyl}fluorene, α,α'-bis(4-hydroxyphenyl)-o-diisopropylbenzene, α, α'-bis(4-hydroxyphenyl)-m-diisopropylbenzene, α,α'-bis(4-hydroxyphenyl)-p-diisopropylbenzene, 1,3-bis(4-hydroxyphenyl) base)-5,7-dimethyladamantane, 4,4'-dihydroxydiphenylsulfone, 4,4'-dihydroxydiphenylsulfoxide, 4,4'-dihydroxydiphenylsulfide, 4,4 '-Dihydroxybenzophenone, 4,4'-dihydroxydiphenyl ether and 4,4'-dihydroxydiphenyl ester, etc. Dihydric phenol can be used individually or in combination of 2 or more types. the

Among them, preferably selected from bisphenol A, 2,2-bis{(4-hydroxy-3-methyl)phenyl}propane, 2,2-bis(4-hydroxyphenyl)butane, 2,2- Bis(4-hydroxyphenyl)-3-methylbutane, 2,2-bis(4-hydroxyphenyl)-3,3-dimethylbutane, 2,2-bis(4-hydroxyphenyl )-4-methylpentane, 1,1-bis(4-hydroxyphenyl)-3,3,5-trimethylcyclohexane and α,α'-bis(4-hydroxyphenyl)-m Dihydric phenols in diisopropylbenzene are used alone or in combination of two or more, particularly preferably bisphenol A alone, or particularly preferably selected from bisphenol A, 2,2-bis{(4-hydroxyl-3-methyl Base) phenyl} propane and α, α'-bis(4-hydroxyphenyl)-m-diisopropylbenzene, one or more dihydric phenols and 1,1-bis(4-hydroxyphenyl)-3 , 3,5-trimethylcyclohexane used in combination. the

The above-mentioned carbonate precursor is not particularly limited as long as it is generally considered to be a compound of a carbonate precursor, and is a carbonate precursor that can be used to manufacture polycarbonate resins and can manufacture the target resin film of the present invention. Examples include carbonyl halides, carbonates, and haloformates. More specifically, examples of the carbonate precursor include phosgene, diphenyl carbonate, dihaloformate of dihydric phenol, and the like. the

The melt volume flow rate (MVR) of the polycarbonate resin at 300°C under a load of 1.2 kg is preferably 11 to 35 cm ³ /10 min, more preferably 12 to 30 cm ³ /10 min, and even more preferably 12 to 25 cm ³ /10 min . When MVR is within a predetermined range, the appearance of the polycarbonate-based resin film for optics can be improved. In addition, MVR is measured based on ISO1133.

The viscosity average molecular weight of the polycarbonate resin is preferably 17,000 to 21,500, more preferably 18,000 to 21,000, and still more preferably 19,000 to 21,000. When the viscosity-average molecular weight is within a predetermined range, the appearance of the polycarbonate-based resin film for optics can be improved. In addition, the viscosity average molecular weight was calculated|required as follows. A 0.5% by weight solution of polycarbonate-based resin using dichloromethane as a solvent was prepared. After measuring the specific viscosity η _sp of the solution at a temperature of 20° C. using a Cannon Finske type viscosity tube, the intrinsic viscosity η was obtained by converting the concentration, and calculated using the following SCHNELL formula (I).

η=1.23×10 ^-4 M ^0.83 (I)

The mold release agent is not particularly limited as long as it is an additive generally recognized as a mold release agent, can be used in the production of polycarbonate-based resins, and can produce the target resin film of the present invention. Generally, the mold release agent may be used as long as it can improve the affinity between the resin and the cooling roll during melt extrusion molding, improve the transfer of the roll surface, or facilitate the release of the resin from the cooling roll. As a mold release agent, alcohol, fatty acid, ester of alcohol and fatty acid, wax, etc. are mentioned, for example. Esters of alcohols and fatty acids are preferred, esters of monohydric alcohols and fatty acids are more preferred, partial or full esters of polyhydric alcohols and fatty acids are more preferred, partial esters of polyhydric alcohols and fatty acids are further preferred. Esters of alcohols and fatty acids may be used alone or in combination of two or more, and partial esters and full esters may be used in combination. It should be noted that a partial ester refers to a compound in which a part of hydroxyl groups of a polyhydric alcohol does not form an ester bond with a carboxyl group of a fatty acid and remains as it is, and a full ester refers to a compound in which all hydroxyl groups of a polyol form an ester bond with a carboxyl group of a fatty acid and does not remain as it is. . Preferred fatty acids are saturated fatty acids. the

Examples of the ester of a monohydric alcohol and a saturated fatty acid include stearyl stearate, palmityl palmitate, butyl stearate, and methyl laurate. the

As partial or full esters of polyhydric alcohols and saturated fatty acids, for example: glycerol monopalmitate, glyceryl dipalmitate, glycerol tripalmitate, glycerol monostearate, glycerol distearate, glycerin Tristearate, Stearinic Acid Monosolbite, Glyceryl Monobehenate, Pentaerythritol Monostearate, Pentaerythritol Distearate, Pentaerythritol Tetrastearate, Pentaerythritol Tetranonanoate, Propylene Glycol Mono Dipentaerythritol such as stearate, biphenylbiphenolate, sorbitan monostearate, 2-ethylhexyl stearate, and dipentaerythritol hexastearate Full ester or partial ester, etc. the

Esters of alcohols and fatty acids are more preferably glyceryl monopalmitate, glyceryl dipalmitate, glyceryl monostearate, glyceryl distearate, stearinic acid monosolbite, glyceryl monobehenate, pentaerythritol Partial esters such as monostearate, pentaerythritol distearate, propylene glycol monostearate, sorbitan monostearate, particularly preferably glycerol monopalmitate, glycerol monostearate, dehydrated Partial esters such as sorbitol monostearate, pentaerythritol monostearate, pentaerythritol distearate, most preferably glycerol monopalmitate and glycerol monostearate. A mold release agent can be used individually or in combination of 2 or more types. the

The content of the release agent in the polycarbonate resin composition is 0.05 parts by weight or less, preferably 0.04 parts by weight or less, more preferably 0.02 parts by weight or less, and particularly preferably 0.008 parts by weight or less. When the content of the mold release agent is more than 0.05 parts by weight, the generation of smoke from the outlet of the die increases during melt extrusion molding. The reason for this is considered to be as follows. the

It is considered that the smoke is not so much generated by the resin in the polycarbonate-based resin composition that is melt-extruded from the die outlet, but rather that the release agent in the resin composition passes through particles with a particle diameter of 0.5 μm or more ( hereinafter referred to as evapotranspiration) in the form of evaporation. This is because it can be seen from the examples described later that the greater the content of the release agent in the polycarbonate resin composition, the greater the generation of evaporatives and the greater the amount of smoke generated. Therefore, evaporative matter adheres to the cover provided on the upper part of the die and condenses, and then, such condensed matter forms liquid droplets and drops on the cooling roll or film, or the evaporated mold release agent directly adheres to the cooling roll or film. on possibility. the

The content of the release agent may be 0.05 parts by weight or less, or 0 parts by weight, based on 100 parts by weight of the polycarbonate-based resin. the

It should be noted that in the polycarbonate resin composition, other components can also be mixed as needed, such as: light diffusing agent, ultraviolet absorber, organic dye, inorganic dye, pigment, antioxidant, antistatic agent and Surfactant etc. the

<Polycarbonate resin film for optics>

The polycarbonate-based resin film for optics of the present invention preferably has at least one surface that is a matte surface (or a matte-treated surface). the

The thickness of the polycarbonate-based resin film for optics is preferably 30 to 300 μm, more preferably 40 to 270 μm, and still more preferably 50 to 250 μm. When the thickness of the polycarbonate-based resin film for optics is too thin, the rigidity of the film itself is reduced, and wrinkles are likely to be generated on the surface of the film. For example, when such a film is bonded to a polarized light separator, the rigidity of the bonded polarized light separator is insufficient, and when such a polarized light separator is used in a liquid crystal display device, it may easily cause Undulating or bending etc. On the other hand, when the thickness of the polycarbonate resin film for optics is too thick, the production cost of the film will be increased, and when the film is bonded to the polarized light separation sheet, the polarized light after bonding will be separated. The thickness of the sheet is thickened, and as a result, the thickness of the liquid crystal panel is thickened. the

The polycarbonate resin film for optics preferably has a total light transmittance of 85% or more as measured in accordance with JIS K7361-1. When the total light transmittance of the film is too low, the ratio of the amount of light emitted from the film to the amount of light incident on the film decreases, resulting in a decrease in light utilization efficiency. the

The haze of the polycarbonate resin film for optics is preferably 50% or more, more preferably 55% or more, and still more preferably 60% or more. When the haze is too low, sufficient light diffusion effect may not be expressed. the

The 60-degree specular gloss of at least one surface of the polycarbonate resin film for optics is preferably 50% or less, more preferably 45% or less, and still more preferably 35% or less. When the 60-degree specular gloss is too large, for example, when the optical film is in contact with a liquid crystal panel, a rainbow pattern will be generated due to interference fringes. the

The in-plane retardation value of the polycarbonate resin film for optics is preferably 30 nm or less, more preferably 20 nm or less, in the case of incident light having a wavelength of 590 nm. the

For example, when the polycarbonate resin film for optics of the present invention is used in a liquid crystal display device, since light used for liquid crystal display is polarized light, a film with small optical strain is required, preferably with a retardation value of 30 nm or less. Especially when the polycarbonate resin film for optics of the present invention is used as a polarized light separator protective film for protecting a polarized light separator for a liquid crystal display device, due to the reasons described later, in order not to disturb as much as possible from the The polarization direction of the polarized light emitted from the polarized light separation sheet preferably has a low retardation value, and more preferably has a retardation value of 20 nm or less. the

As shown in FIG. 2 , the liquid crystal display device is configured such that a liquid crystal panel 11 is provided on a backlight unit 8 so that light emitted from the backlight unit 8 enters the liquid crystal panel 11 . The polarized light separator 9 is usually disposed between the backlight unit 8 and the liquid crystal panel 11 . The polarized light separator 9 separates the non-polarized light (unpolarized light) emitted from the backlight unit 8 into two kinds of polarized light (polarized light) perpendicular to each other, selectively passes only one polarized light, and emits On the liquid crystal panel 11 side, another polarized light returns to the backlight unit 8 side. After the returned polarized light is reflected in the backlight unit, it is incident on the polarized light separating sheet 9 again and reused. Therefore, using the polarized light separating sheet 9 can improve the utilization efficiency of light. Therefore, in order to not disturb the polarized light emitted from the sheet 9 as much as possible for the polarized light separating sheet protective film 10 that is laminated or bonded on both sides or one side of the sheet 9 in order to protect the polarized light separating sheet 9 In the polarization direction, the retardation value is preferably low, and the retardation value is more preferably 20 nrn or less. the

<Manufacturing process of polycarbonate resin film for optics>

The polycarbonate-based resin film for optics of the present invention is preferably produced from the above-mentioned polycarbonate-based resin composition, and at least one side thereof is a matte surface. the

Examples of a method for producing an optical polycarbonate-based resin film include a method of melt-extruding the above-mentioned polycarbonate-based resin composition, a method of forming a film from a solution of the resin composition, and the like. Among them, the method of melt extrusion can suppress the generation of smoke from the outlet of the die when molding the polycarbonate resin film for optics, so it is preferred. the

As a method of forming the matte surface, examples can be given: when melt-extruding a resin film, use a metal roller (so-called matte roller) with a concave-convex shape formed on the outer peripheral surface, and transfer the unevenness of the metal roller; A method of melt-extruding a polycarbonate-based resin of transparent particles of an agent to form irregularities on the surface of a resin film, etc. the

The polycarbonate resin film for optics only needs to mainly contain polycarbonate resin, and other resins may also be mixed. In addition, it may be a two-layer multilayer film obtained by multilayer melt extrusion molding with other resins. , It can also be two kinds of three-layer multilayer films. In the case of a multilayer film, additives such as light diffusing agents, ultraviolet absorbers, organic dyes, inorganic dyes, pigments, antioxidants, antistatic agents, and surfactants can be added to either layer or over two floors. the

<Method of forming a matte surface using a roller>

The method of forming a matte surface using a so-called matte roll is to use a metal roll with a concave-convex shape formed on the outer peripheral surface to transfer the concave-convex shape to the resin film when melt-extruding a resin film, for example: JP2009- 196327A, the method described in JP2009-202382A, etc. the

FIG. 1 is an explanatory schematic diagram showing an example of a production process of the polycarbonate resin film for optics of the present invention (hereinafter, referred to as the production process of the present invention). the

As shown in the figure, the manufacturing process is to prepare a melt extruder 1, melt knead the polycarbonate-based resin composition put into the extruder, pass through a polymer filter 2, and pass through a die 3 (T die). ), the resin is spread out and extruded as a film from the die outlet. the

The polymer filter 2 is not particularly limited as long as it is a polymer filter capable of producing the target resin film of the present invention. For example, it is preferable to stack about 10 to 80 leaf disk filters of about 3 to 12 inches. A commercially available polymer filter can be used to form the polymer filter. As the filter pore size of the polymer filter 2, any aggregates of rubber-like polymers can be filtered. Specifically, the filter pore diameter of the polymer filter 2 is preferably 5 to 20 μm, more preferably 5 to 15 μm, from the viewpoint of suppressing occurrence of surface defects in the resulting membrane. the

The die 3 is not particularly limited as long as it is a die that can obtain the target resin film of the present invention, and a T-type die is usually used. As for the die 3, when the polycarbonate-based resin film for optics is a single-layer film, it is preferable to extrude a single-layer die of one resin in a single layer, a multi-layer film of two types or two layers. In the case of a three-layer multilayer film, etc., a multilayer die in which two or more resins independently pressure-fed from an extruder are laminated and co-extruded is preferably used as a multilayer die, preferably a feed block die. head (feed block die) or multi-channel die (multi manifold die). the

Next, the resin extruded from the die head 3 is sandwiched between the first cooling roll 4 and the second cooling roll 5 arranged to face each other in a substantially horizontal direction. Preferably, at least one surface is formed into a matte surface, and the polycarbonate-based resin film 7 for optics can be obtained by gradually cooling with the third cooling roll 6 . the

The first cooling roll 4 is not particularly limited as long as the target resin film of the present invention can be obtained, and ordinary metal rolls or the like currently used in extrusion molding can be used. Generally, a rubber roller or a metal elastic roller with a diameter of about 25 to 100 cm is preferred. By setting the first cooling roller 4 as a rubber roller or a metal elastic roller, the retardation value of the obtained polycarbonate resin film for optics can be made to be 30 nm or less. the

Examples of the rubber roller include silicone rubber rollers and fluororubber rollers, and sand-mixed rollers may be used in order to improve releasability. The hardness of the rubber roller is preferably within the range of A60° to A90° measured in accordance with JIS K6253. In order to make the hardness of a rubber roller into the said range, it can arbitrarily perform, for example by adjusting the degree of crosslinking and composition of the rubber which comprises a rubber roller. the

The above-mentioned metal elastic roller is generally made of rubber or fluid inside the roller, and its outer peripheral part is made of a flexible metal thin film. More specifically, examples include: a roll in which the inside of the roll is made of a silicone rubber roll, and a cylindrical stainless steel film with a thickness of about 0.2 to 1 mm covering the outer periphery of the roll; a roll with a thickness of about 2 to 5 mm. A cylindrical film made of stainless steel is fixed to the end of the roll, and a roll such as water or oil is sealed inside. the

As such a first cooling roll 4, it is preferable to use a cooling roll made of a metal material or an elastic body and processed into a mirror-like surface by gold plating or the like. It should be noted that the metal thin film of the metal elastic roll or the surface of the rubber roll does not necessarily have to be smooth, and unevenness may be provided on the surface like the second cooling roll 5 described later. the

The second cooling roll 5 is not particularly limited, and common metal rolls currently used in extrusion molding can be used, and metal rolls with a diameter of about 25 to 100 cm are generally preferred. the

In order to form a matte surface on the resin film, it is preferable to form concavo-convex shapes on the outer peripheral surface of such a metal roller. More specifically, examples include metals that can control the temperature of the roll surface by allowing fluid, steam, etc. Roller etc. Rolls in which the desired unevenness is formed on the outer peripheral surface of these metal rolls by sandblasting, engraving, or the like can be used. the

As the concave-convex shape formed on the outer peripheral surface of the second cooling roll 5, there can be exemplified: a mat-shaped (mat shape) having a specific pitch and height in terms of arithmetic mean roughness (Ra) of about 0.1 to 10 μm. shape etc. The above arithmetic average roughness (Ra) is a value measured with a surface roughness meter in accordance with JIS B0601-2001. the

In addition, what is necessary is just to insert this resin between the cooling rolls which formed the said uneven|corrugated shape on the outer peripheral surface, when forming the matte layer on both surfaces of a film. the

The polycarbonate-based resin film for optics capable of transferring the concavo-convex shape is wound up on the second cooling roll 5, and then taken up by a take-up roll. In this case, the third cooling roll 6 may be provided after the second cooling roll 5 . Thus, the polycarbonate resin film for optics can be cooled slowly, so the optical strain of the film can be reduced, and the contact time with the second cooling roller 5 can be stably ensured, so that the transfer can be performed stably. Concavo-convex shape formed on the second cooling roll 5 . the

The third cooling roll 6 is not particularly limited as long as the target resin film of the present invention can be obtained, and ordinary metal rolls or the like currently used in extrusion molding can be used. Specific examples include drilled press rolls, spiral rolls, and the like. The surface state of the third cooling roll 6 is preferably a mirror surface. the

The resin film wound on the second cooling roll 5 is wound on the third cooling roll 6 by passing between the second cooling roll 5 and the third cooling roll 6 . A predetermined gap may be provided between the second cooling roll 5 and the third cooling roll 6 to be in a released state, or both rolls may be inserted. It should be noted that, in order to cool the resin film more slowly, the fourth cooling roll, the fifth cooling roll ... a plurality of cooling rolls may be installed after the third cooling roll 6, and the The resin film (preferably matte film) is wound on the next cooling roll in turn. the

<Method of forming matte surface using matting agent>

In addition, as another method of forming the matte surface, it is possible to use a resin blended with transparent fine particles as a matting agent to form irregularities on the surface by melt extrusion molding. In particular, in the case of using a matting agent, it is preferable to use a method of forming roughness on the surface by blending particles of the matting agent only in the resin forming the surface layer in multilayer melt extrusion molding. Usually, when adding a matting agent to obtain surface roughness, it is necessary to add a certain amount of matting agent. From the viewpoint of cost, generally, in the multilayer melt extrusion molding, only the resin forming the surface layer contains the matting agent. method. As the multilayer extrusion molding method at this time, the methods described in the aforementioned JP2009-196327A and JP2009-202382A can be exemplified. In this case, since the unevenness of the surface is formed by the effect of the matting agent, the second cooling roll 5 may be a metal roll whose surface state is usually a mirror surface. the

In addition, the matting agent used at this time generally uses what is called a light-diffusion agent particle|grains. As the light diffusing agent, for example: organic particles such as methyl methacrylate polymer particles, styrene polymer particles, and siloxane polymer particles; calcium carbonate, barium sulfate, titanium oxide, aluminum hydroxide , silica (silicon oxide), inorganic glass, talc, mica, white carbon black, magnesium oxide, zinc oxide and other inorganic particles. It should be noted that the inorganic particles may be surface-treated with a surface treatment agent such as fatty acid so as to be uniformly dispersed in the thermoplastic resin. the

The polycarbonate-based resin film for optics of the present invention is often required to have a high total light transmittance as an optical characteristic, and therefore, particles having good transparency can be preferably used as a matting agent. In addition, from the viewpoint of adding a matting agent to the extent that the unevenness of the surface can be ensured and maintaining a high total light transmittance, it is preferable that the difference between the refractive index of the base resin and the refractive index of the matting agent is not too large, Usually, it is preferable that the difference in refractive index is within about 0.1. In multilayer melt extrusion molding, it is preferable to select particles that do not have a large difference in refractive index from the resin forming the surface layer. In addition, the matting agent used can be used individually or in combination of 2 or more types. the

The methyl methacrylate polymer particles used as the above-mentioned matting agent are polymer particles mainly composed of methyl methacrylate, and the polymer preferably has one polymerizable polymer particle in the molecule other than methyl methacrylate. A cross-linked polymer formed by copolymerization of monofunctional monomers with double bonds and multifunctional monomers with more than two polymerizable double bonds in the molecule. the

Examples of monofunctional monomers other than methyl methacrylate in the above-mentioned methyl methacrylate-based polymer particles include methyl methacrylate, which was mentioned above as an example of a monomer for methyl methacrylate-based resins. As (meth)acrylates other than esters, styrene-based monomers, and polymerizable monofunctional monomers other than (meth)acrylates and styrene-based monomers, styrene is preferably used. the

Examples of the polyfunctional monomer in the above-mentioned methyl methacrylate polymer particles include 1,4-butanediol dimethacrylate, neopentyl glycol dimethacrylate, ethylene glycol dimethyl Acrylate, diethylene glycol dimethacrylate, tetraethylene glycol dimethacrylate, propylene glycol dimethacrylate Methacrylates of polyhydric alcohols such as ethylene glycol dimethacrylate (Tetra propilen etileng ricol jimetacrylet), trimethylolpropane trimethacrylate, pentaerythritol tetramethacrylate; 1,4 - Butylene glycol diacrylate, neopentyl glycol diacrylate, ethylene glycol diacrylate, diethylene glycol diacrylate, tetraethylene glycol diacrylate, propylene glycol diacrylate (Propilen Acrylates of polyalcohols such as Echinelene Glycol Jiacrylite, Tetrapropylene Glycol Diacrylate, Trimethylolpropane Triacrylate, Pentaerythritol Tetraacrylate Classes; aromatic polyfunctional compounds such as divinylbenzene, diallyl phthalate, etc. Such polyfunctional monomers can be used alone or in combination of two or more. the

The refractive index of such methyl methacrylate polymer particles is generally about 1.46 to 1.55, and the larger the content of benzene skeleton or halogen atom, the larger the refractive index tends to be. For the methyl methacrylate polymer particles, for example, methods such as suspension polymerization, microsuspension polymerization, emulsion polymerization, and dispersion polymerization can be used to manufacture,

The styrene-based polymer particles used as the above-mentioned matting agent are polymer particles mainly composed of styrene, and the polymer is preferably a monofunctional monomer having a polymerizable double bond in a molecule other than styrene, A cross-linked polymer obtained by copolymerizing multifunctional monomers with two or more polymerizable double bonds in the molecule. the

As the monofunctional monomer other than styrene in the above-mentioned styrene-based polymer particles, for example, in addition to methyl methacrylate, the aforementioned examples of monomers for methyl methacrylate-based resins can also be exemplified. (meth)acrylates other than methyl methacrylate, styrene-based monomers, and polymerizable monofunctional monomers other than (meth)acrylates and styrene-based monomers, preferably methyl methacrylate ester. the

As the polyfunctional monomer in the above-mentioned styrene-based polymer particles, for example, the polymerizable polyfunctional monomers mentioned above as examples of the polyfunctional monomer of the methyl methacrylate-based polymer particles can also be exemplified, It can be used individually or in combination of 2 or more types, respectively. the

The refractive index of such styrene-based polymer particles is generally about 1.53 to 1.61, and the larger the content of benzene skeletons or halogen atoms, the larger the refractive index tends to be. The styrene-based polymer particles can be produced, for example, by methods such as suspension polymerization, microsuspension polymerization, emulsion polymerization, and dispersion polymerization. the

The ratio of the polyfunctional monomer used in the methyl methacrylate polymer particles and styrene polymer particles used as the matting agent is usually about 0.05 to 15% by mass, preferably about 0.05% to 15% by mass, based on all monomers. 0.1 to 10% by mass. When the amount of the polyfunctional monomer is too small, the degree of crosslinking of the particles is insufficient, and the particles are easily deformed significantly when heat or shear is applied during extrusion molding, and as a result, it is difficult to obtain the desired light diffusion effect. In addition, when the amount of the polyfunctional monomer is too large, poor appearance is likely to occur during extrusion molding. the

The siloxane-based polymer particles used as the matting agent are polymer particles produced by, for example, hydrolyzing and condensing chlorosilanes. the

As the chlorosilanes, for example, dimethyldichlorosilane, diphenyldichlorosilane, phenylmethyldichlorosilane, methyltrichlorosilane, phenyltrichlorosilane, and the like may, for example, be mentioned. Silicone polymers can be crosslinked. For crosslinking, for example, benzoyl peroxide, 2,4-dichlorobenzoyl peroxide, p-chlorobenzoyl peroxide, dicumyl peroxide, di-tert-butyl peroxide , Peroxides such as 5-dimethyl-2,5-(t-butylperoxy)hexane act on silicone-based polymers. Moreover, when it has a terminal silanol group, condensation crosslinking with alkoxysilanes is also possible. The crosslinked polymer preferably has a structure in which about 2 to 3 organic residues are bonded to each silicon atom. the

As such a siloxane-based polymer, it is preferable to use a siloxane-based polymer that is solid at normal temperature and is also called a polymer of silicone rubber or a silicone resin. Silicone polymer particles can be obtained by pulverizing such a silicone polymer. Granular particles can also be formed by curing a curable polymer having a linear organosiloxane block or a composition thereof in a spray state. In addition, it can also be obtained in the form of granular particles by subjecting alkyltrialkoxysilane or its partial hydrolysis-condensation product to hydrolysis-condensation in an aqueous solution of ammonia or amines. the

The refractive index of such siloxane-based polymer particles is usually about 1.40 to 1.47. the

The weight-average particle diameter of the particles used as a matting agent may be appropriately selected according to the desired surface unevenness, but in order to have the desired surface unevenness and excellent optical properties, it is preferably 0.5 to 50 μm, more preferably It is 1 to 40 μm, more preferably 2 to 30 μm. In addition, the particles are generally spherical, but particles having shapes such as rectangles, scales, needles, and plates can also be used. the

The compounding ratio of the particles serving as a matting agent in the surface layer during multilayer extrusion is preferably 35% by weight or less, more preferably 30% by weight or less, based on 100% by weight of the total amount of resin and particles. When the blending ratio of the particles exceeds 35% by weight, it may be difficult to melt-extrude the resin blended with the particles. the

The polycarbonate resin film for optics of the present invention is used for various purposes such as diffusion action, angle change action, prevention of adhesion with other parts, and protection of the surface of the film by contact with other parts. For example, in liquid crystal display devices Among them, it can be used to insert the light diffusion film of the backlight unit, the protective film of the polarizer, the retardation film, the brightness enhancement film, etc., the protective film of the polarized light separator, the reflective film, and the light guide film. Moreover, it can also be applied to an optical disc, a film for lighting, etc., and this invention is not limited to these uses. In particular, it can be preferably used as a protective film of a polarized light separator in a liquid crystal display device. the

Example

Examples of the present invention are shown below, but the present invention is not limited to these Examples. It should be noted that, in the following examples, unless otherwise specified, the parts indicating content and usage are parts by weight. the

The configurations of the extruders used in the following examples and comparative examples are as follows. the

Melting extruder 1: Single-screw extruder (manufactured by Toshiba Machine Co., Ltd.) with a screw diameter of 115 mm and a vent port

Polymer filter 2: filter pore size is 10μm

Die 3: T-shaped die (single-layer die)

As shown in FIG. 1 , a melt extruder 1 , a polymer filter 2 , a die 3 , and first to third cooling rolls 4 to 6 are arranged, and the first to third cooling rolls 4 to 6 are configured as follows. the

<Roll Composition> 

The first cooling roll 4, the second cooling roll 5, and the third cooling roll 6 are configured as follows. the

The first cooling roll 4: the outer diameter is Silicone rubber roller with hardness A70°

The second cooling roll 5: the outer diameter is A stainless steel metal roll (drilled press roll) with an arithmetic average roughness (Ra) of 3.5 μm formed by sandblasting

镜面加工了的不锈钢制的金属辊(钻孔压辊)  3rd cooling roll 6: the outer diameter is

Mirror-finished stainless steel metal roll (drilled press roll)

The polycarbonate-based resins and release agents used in the following examples and comparative examples are as follows. the

As the polycarbonate resin, "Caliba-301-15" (trade name) manufactured by Sumitomo Dou Co., Ltd. having an MVR of 14 cm ³ /10 min under a load of 1.2 kg at 300° C. and a viscosity average molecular weight of 20,200 was used.

As the release agent, glyceryl monopalmitate and glyceryl monostearate were used. the

(Examples 1-4, Comparative Example 1)

的单螺杆熔融挤出机1，使其通过设置在模头3的前面的过滤器孔径为10μm的高分子过滤器2之后，从模头3(模头温度：255℃)以300kg/hr的吐出量挤出膜状的树脂。将挤出的膜状的树脂夹入第1冷却辊4(设定温度：34℃)和第2冷却辊5(设定温度：130℃)之间，卷绕在第2冷却辊5上，接着，通过第2冷却辊5和第3冷却辊6(设定温度：135℃)之间，进而卷绕在第3冷却辊上，连续成型24小时一面转印有第2冷却辊的凹凸形状的厚度为130μm的光学用聚碳酸酯系树脂膜7。实施例1～4以及比较例1的各光学用聚碳酸酯系树脂膜7的从第2冷却辊的脱模性均良好。需要说明的是，膜的厚度使用测微计(Mitutoyo公司制，MDC-25MJ)进行测定。  The polycarbonate-based resin compositions of Examples 1 to 4 and Comparative Example 1 containing a polycarbonate-based resin and a mold release agent in the ratio shown in Table 1 were prepared. Each polycarbonate resin composition is supplied

The single-screw melt extruder 1 made it pass through the polymer filter 2 with a filter pore size of 10 μm arranged in front of the die 3, and then from the die 3 (die temperature: 255° C.) at a rate of 300 kg/hr The amount of discharge extrudes the film-like resin. The extruded film-like resin is sandwiched between the first cooling roll 4 (set temperature: 34°C) and the second cooling roll 5 (set temperature: 130°C), and wound on the second cooling roll 5, Next, it passes between the second cooling roll 5 and the third cooling roll 6 (set temperature: 135°C), and then is wound on the third cooling roll, and continuously molded for 24 hours while the uneven shape of the second cooling roll is transferred. Optical polycarbonate-based resin film 7 with a thickness of 130 μm. The releasability from the 2nd cooling roll of each polycarbonate-type resin film 7 for optics of Examples 1-4 and Comparative Example 1 was favorable. In addition, the thickness of a film was measured using the micrometer (Mitutoyo company make, MDC-25MJ).

Table 1

＊1: Total amount = Glyceryl monopalmitate content + Glyceryl monostearate content

The following evaluations were performed on each optical polycarbonate-based resin film (Examples 1 to 4 and Comparative Example 1) obtained after continuous molding for 24 hours. The results are shown in Table 2 and Table 3. the

<Total light transmittance (Tt) and haze (H)>

According to JIS K7361-1, the total light transmittance (Tt) of the polycarbonate resin film for optics was measured. the

According to JIS K7136, the haze (H) of the polycarbonate resin film for optics was measured. the

<delay value>

A test piece with a size of 50 mm square was cut out from the obtained polycarbonate resin film for optics, and was measured using a micro-area birefringence meter ("KOBRA-CCO/X" (trade name) manufactured by Oji Scientific Instruments Co., Ltd.). The retardation value of the resin film when incident light with a wavelength of 590nm is used. 

<surface gloss>

According to JIS Z8741, the 60-degree glossiness of the matte surface (the surface which contacts with the 2nd cooling roll, that is, the surface which carried out the matte treatment) of the polycarbonate resin film for optics obtained was measured. the

<smoke>

During melt extrusion molding of the polycarbonate-based resin film for optics, fume from the outlet of the die 3 was visually observed. When almost no smoke was generated, it was judged as "⊚", when there was little smoke, it was judged as "◯", and when there was much smoke, it was judged as "×". the

<Number of evapotranspiration>

During melt extrusion molding of the polycarbonate-based resin film for optics, the number of objects of evaporated matter generated from the outlet of the die 3 was measured with a particle counter (manufactured by MetOne). the

First, the measurement was performed with 1 liter of air around the extruder as a blank, and the gas present in the particle counter was replaced with the air around the extruder. Next, on the die head 3 of the shape shown in FIG. 1. Set up a suction probe at a position 10 cm high from the exit of the die head 3 . Then, the air was sucked with the suction probe for about 10 seconds, and the number of evaporatives in each particle size range existing in the sucked air equivalent to 1 liter was measured. the

Table 2

the Total light transmittance (%) Haze (%) Delay (nm) Surface gloss (%) smoke Example 1 89 78 8 13 ◎ Example 2 89 76 9 14 ◎ Example 3 89 77 7 13 ◎ Example 4 89 78 10 14 ○ Comparative example 1 89 77 9 14 ×

table 3

The optical polycarbonate-based resin films of Examples 1 to 4 can be used as protective films of polarized light separators in liquid crystal display devices. the

Claims (13)

1. A method for producing a polycarbonate-based resin film for optics, comprising melt-extruding a polycarbonate-based resin composition, characterized in that, The polycarbonate-based resin composition contains 0.05 parts by weight or less of a mold release agent with respect to 100 parts by weight of the polycarbonate-based resin. 2. The method for producing an optical polycarbonate-based resin film according to claim 1, wherein the release agent is an ester of an alcohol and a fatty acid. 3. The method for producing an optical polycarbonate-based resin film according to claim 2, wherein the release agent is an ester of a polyhydric alcohol and a fatty acid. 4. The method for producing an optical polycarbonate resin film according to claim 3, wherein the release agent is a partial ester of a polyhydric alcohol and a fatty acid. 5. The method for producing an optical polycarbonate resin film according to any one of claims 1 to 4, wherein the thickness of the optical polycarbonate resin film is 30 to 300 nm, and the total light transmittance is More than 85%. 6 . The method for producing an optical polycarbonate-based resin film according to claim 1 , wherein the optical polycarbonate-based resin film has a haze of 50% or more. 7 . The method for producing an optical polycarbonate-based resin film according to claim 1 , wherein the optical polycarbonate-based resin film has a surface gloss of 50% or less. 8. The manufacturing method of a polycarbonate resin film for optics according to any one of claims 1 to 7, wherein the retardation of the polycarbonate resin film for optics is lower when the wavelength of incident light is 590 nm. below 30nm. 9 . The method for producing an optical polycarbonate-based resin film according to claim 1 , wherein at least one surface of the optical polycarbonate-based resin film is a mat surface. 10 . The method for producing an optical polycarbonate-based resin film according to claim 9 , comprising forming a mat surface using a mat roller. 11 . The polycarbonate-type resin film for optics obtained by the manufacturing method in any one of Claims 1-10. 12. The polycarbonate-based resin film for optics according to claim 11, which is used for liquid crystal display transposition. 13. The polycarbonate-based resin film for optics according to claim 12, which is used to protect a polarized light separator in the liquid crystal display device.

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