JP2005187566A - Polyester film for molding and molded member obtained from the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a polyester film for molding which is excellent in moldability at the time of heat molding and gives a molded item exhibiting excellent rigidity and shape stability (heat shrinkage characteristics and thickness unevenness), and good printability, printing durability and printing operability when used in an ordinary temperature atmosphere, and a molded member obtained by molding the same. <P>SOLUTION: The polyester film for molding comprises a copolyester composed of an aromatic dicarboxylic acid component and a glycol component comprising ethylene glycol, and a branched aliphatic glycol and/or an alicyclic glycol, where the film has stress at 100% elongation, each in the longitudinal direction and in the width direction, of 180-1,000 MPa at 25°C and 1-100 MPa at 100°C and intrinsic viscosity of at least 0.58 dL/g and has a printability-improving layer comprising an adhesive property-improving resin formed at least on one surface. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention is excellent in moldability such as insert moldability and emboss moldability, particularly moldability in mold molding and insert molding, and further excellent in printability, transparency and heat resistance, for home appliances, automobile nameplates or building materials. The present invention relates to a molding polyester film suitable as a member and a molding member using the same.

  Conventionally, as a sheet for processing, a polyvinyl chloride film is typical and has been preferably used in terms of workability. On the other hand, the film has problems such as generation of toxic gas when the film burns due to fire and the like, and problems such as bleed out of the plasticizer, and new materials have been demanded according to recent needs for environmental resistance.

  Conventionally, by using a copolymer polyester containing a long-chain linear aliphatic dicarboxylic acid component having 3 or more carbon atoms and / or a long-chain linear aliphatic glycol component as a film raw material, moldability is improved. There are many technical disclosures to be improved. However, the polyester resin is softened by these copolymer components, and has the disadvantages that it has poor strength and rigidity when it is actually used as a molded product, as well as poor stability. In order to increase the stability, if the copolymer composition ratio of the above components is decreased, the moldability is lowered, and it is difficult to achieve both moldability, strength and rigidity.

For example, a polyester film for molding made of polyester containing neopentyl glycol as a copolymerization component is known as the copolymer polyester (see, for example, Patent Documents 1 and 2). Since the polyester film for copolymer molding described in these conventional techniques has a thickness of 50 μm or less, it is relatively easy to form a film.
JP-A-1-252658 Japanese Unexamined Patent Publication No. 1-445699

  However, when the thickness exceeds 50 μm, the co-polyester inherently has a tendency of insufficient control of molecular orientation from the viewpoint of stress reduction during stretching and crystallinity. Stability may be insufficient. Therefore, there has been a demand for a molding polyester film that is excellent in rigidity and shape stability (heat shrinkage characteristics, thickness unevenness) when using a molded body in a room temperature atmosphere while maintaining moldability.

The present inventors have already proposed an invention relating to a molding polyester film having a specific range of 100% elongation stress at 25 ° C. and 100 ° C. in the longitudinal direction and the width direction of the film (see Patent Document 3). . According to the invention, the problems of the prior art are solved, the moldability at the time of heat molding is excellent, and the rigidity and form stability (heat shrinkage characteristics, thickness unevenness) when used in a room temperature atmosphere as a molded body. An excellent polyester film for molding can be obtained.
Japanese Patent Application No. 2002-233694

  However, there is room for further improvement in terms of productivity reduction due to breakage of the base film, especially when molding is performed by a molding method that has a high degree of deformation during molding and a high molding speed, such as mold molding and insert molding. was there. There is also room for further improvement in printability, printing durability, printing operability, and the like.

  The object of the present invention is to solve the problems of the prior art, have excellent moldability at the time of heat molding, and when used as a molded body in a room temperature atmosphere, rigidity and shape stability (heat shrinkage characteristics, thickness unevenness) The present invention provides a molding polyester film suitable for molding applications and a molded member using the same, which is excellent in printing properties, printing durability, and printing operability.

  That is, the present invention is a polyester film for molding containing a copolymerized polyester composed of an aromatic dicarboxylic acid component and ethylene glycol and a glycol component containing a branched aliphatic glycol and / or an alicyclic glycol. The film has a 100% elongation stress in the longitudinal and width directions of 180 to 1000 MPa at 25 ° C. and 1 to 100 MPa at 100 ° C., and an intrinsic viscosity of 0.58 dl / g or more, and at least on one side. It is a polyester film for molding characterized by providing a printability improving layer containing an adhesive modification resin.

  Moreover, this invention is a polyester film for shaping | molding characterized by using the said polyester film for shaping | molding as a shaping | molding member. Furthermore, the present invention is a molded member using the molding polyester film.

  In the polyester film for molding of the present invention, the stress at 100% elongation in the longitudinal direction and the width direction of the film is independently controlled at 25 ° C. and 100 ° C., and the intrinsic viscosity of the polyester film for molding is in a specific range. Therefore, it is excellent in moldability at the time of heating, rigidity and shape stability (thickness unevenness, heat shrinkage characteristics) at the time of use as a molded body. Moreover, it is excellent in moldability in molding methods such as mold molding and insert molding, and also has good printability, printing durability, and printing operation.

  The polyester film for molding according to the present invention includes a copolyester composed of an aromatic dicarboxylic acid component and a glycol component containing ethylene glycol and a branched aliphatic glycol and / or alicyclic glycol. The branched aliphatic glycol and / or alicyclic glycol has a side chain or cyclic structure that suppresses mobility such as free rotation of the molecule, and glass is obtained by copolymerizing such monomers. The melting point (Tm) can be lowered and the elongation at break can be increased without lowering the transition temperature (Tg).

  The polyester film for molding of the present invention using such a copolymerized polyester as a film raw material has excellent moldability in a high temperature atmosphere during molding, and rigidity and shape stability in a normal temperature atmosphere used as a molded body ( The polyester film for molding has a feature that it is excellent in heat shrink characteristics and thickness unevenness, and is particularly suitable for molding applications.

  The above-mentioned features can be expressed by physical properties of stress at 100% elongation in the longitudinal direction and width direction of 180 to 1000 MPa at 25 ° C. and 1 to 100 MPa at 100 ° C.

  The stress at 100% elongation in a 25 ° C. atmosphere in the longitudinal direction and the width direction of the film is 180 to 1000 MPa from the viewpoint of achieving both rigidity and form stability (thickness unevenness, thermal shrinkage at 150 ° C.) and moldability. It is important that

  The lower limit of the stress at 100% elongation at 25 ° C. is preferably 210 MPa, particularly preferably 220 MPa, from the viewpoint of rigidity and thickness unevenness in a normal temperature atmosphere when using a molded body.

  On the other hand, in a film having a high rigidity such that the stress at 100% elongation in the 25 ° C. atmosphere exceeds 1000 MPa, the moldability at the time of heat molding tends to deteriorate.

  It is important that the stress at 100% elongation in an atmosphere of 100 ° C. in the longitudinal direction and the width direction of the film is 1 to 100 MPa from the viewpoint of moldability.

  The lower limit value of the stress at 100% elongation in the 100 ° C. atmosphere is preferably 5 MPa, particularly preferably 10 MPa. In a field where high deformability is required, a small stress at 100% elongation in an atmosphere of 100 ° C. is a desirable direction from the viewpoint of moldability. However, if the stress at 100% elongation in a 100 ° C. atmosphere decreases, the stress at 100% elongation at 25 ° C. also decreases, and the rigidity and thickness unevenness in a normal temperature atmosphere tend to deteriorate.

  On the other hand, the stress at 100% elongation at 100 ° C. is preferably 90 MPa, particularly preferably 80 MPa, from the viewpoint of moldability during heat molding.

  From the viewpoint of moldability, the breaking elongation at 100 ° C. is preferably 150% or more, more preferably 170% or more, and particularly preferably 200% or more.

  From the viewpoint of shape stability, the elongation at break at 25 ° C. is preferably 130% or more, more preferably 150% or more, and particularly preferably 170% or more.

  In the present invention, the change rate of the stress at 100% elongation in the longitudinal direction and the width direction at 100 ° C. as the temporal stability of workability ((after 1 month of film formation-immediately after film formation) × 100 / immediately after film formation) However, it is preferable that both are ± 20% or less. More preferably, it is ± 10% or less, and particularly preferably ± 5% or less.

  The thickness of the polyester film for molding of the present invention is 50 to 500 μm from the viewpoints of moldability, covering properties when a printed layer is provided to enhance the design properties of the film, film surface protection properties, and design properties. preferable. The lower limit of the film thickness is preferably 60 μm, particularly preferably 70 μm. On the other hand, the upper limit value of the film thickness is preferably 300 μm, particularly preferably 200 μm.

  The film thickness unevenness is preferably 5.5% or less. If the thickness unevenness exceeds 5.5%, the printability and dimensional stability tend to deteriorate.

  Furthermore, the fact that the thermal shrinkage rate in the longitudinal direction and the width direction at 150 ° C. of the film is 6.0% or less reduces printing misalignment after providing a printing layer on the molding polyester film in order to enhance the design. To preferred.

  The film preferably has a haze H (%) ratio (H / d) to a thickness d (μm) of 0.030 or less from the viewpoint of transparency and print sharpness. The H / d is more than 0 and preferably 0.025 or less, particularly preferably 0.015 or less.

  The lower limit of the H / d is preferably closer to zero, but if the necessary minimum unevenness is not formed on the film surface, handling properties such as slipperiness and rollability will deteriorate, the film surface will be scratched or produced. Sex is likely to deteriorate. In the case of a translucent nameplate using a backlight or the like, a high degree of transparency is required. Therefore, the H / d is preferably closer to zero.

  Since the intrinsic viscosity of the polyester film for molding of the present invention is 0.58 dl / g or more, the degree of deformation is particularly high during molding, such as a mold molding method and insert molding method, and the molding speed is high. Even if the film is molded by the molding method, the film can be beautifully and withstand high-speed molding without breaking.

  The molding polyester film of the present invention preferably has a melting point of 220 to 245 ° C. By controlling the melting point of the film within the above range, in addition to the above characteristics, even if the molding method or insert molding method is used, the pattern of the molded product may be distorted or the surface of the molded product may be rough. It is possible to suppress deterioration of so-called finish properties, such as causing appearance defects. The melting point is more preferably 220 to 240 ° C.

  Furthermore, since the polyester film for molding of the present invention is provided with an easy-printability improving layer containing an adhesive modification resin on one side of the base film, high-quality printing is possible. In particular, since the water resistance of the printability improving layer is improved, it can be suitably used in the field of molded articles used under high humidity conditions.

  In the molding film of the present invention, since the slipperiness improving layer containing particles and / or wax is laminated on the opposite surface of the printability improving layer, the operability during printing is improved.

  By controlling the light transmittance at a wavelength of 380 nm to 50% or less in the molding film of the present invention, for example, the light resistance of the printing polyester film of the present invention, particularly for printing applied for decoration, is improved. Do

Hereinafter, preferred embodiments of the present invention will be described in detail.
The polyester in the present invention means a general term for high molecular weight substances constituted by ester bonds.

  In the polyester film for molding of the present invention, a copolymer polyester composed of an aromatic dicarboxylic acid component and ethylene glycol and a glycol component containing a branched aliphatic glycol and / or an alicyclic glycol is used as part of the film raw material. Or 100% used.

  In the copolymerized polyester, the aromatic dicarboxylic acid component is mainly composed of terephthalic acid or an ester-forming derivative thereof. The amount of the terephthalic acid component with respect to the total dicarboxylic acid component is 70 mol% or more, preferably 85 mol% or more, particularly preferably. Is 95 mol% or more, and particularly preferably 100 mol%.

  Examples of the branched aliphatic glycol include neopentyl glycol, 1,2-propanediol, and 1,2-butanediol. Examples of the alicyclic glycol include 1,4-cyclohexanedimethanol and tricyclodecane dimethylol.

  Among these, neopentyl glycol and 1,4-cyclohexanedimethanol are particularly preferable, and the stress at 100% elongation in the longitudinal direction and the width direction of the film defined in the present invention is 180 to 1000 MPa at 25 ° C. and 100 ° C. It is effective for satisfying 1 to 100 MPa. Furthermore, it is not only excellent in moldability and transparency, but also excellent in heat resistance, and is preferable from the viewpoint of improving adhesion to a coating layer such as a printing layer.

  Furthermore, you may use together the following dicarboxylic acid component and / or glycol component as a copolymerization component in the said copolyester as needed, if necessary.

  Other dicarboxylic acid components that can be used in combination with terephthalic acid or its ester-forming derivatives include (1) isophthalic acid, 2,6-naphthalenedicarboxylic acid, diphenyl-4,4′-dicarboxylic acid, diphenoxyethanedicarboxylic acid Aromatic dicarboxylic acids such as acid, diphenylsulfone dicarboxylic acid, 5-sodium sulfoisophthalic acid, phthalic acid or their ester-forming derivatives, (2) oxalic acid, succinic acid, adipic acid, sebacic acid, dimer acid, maleic acid Aliphatic dicarboxylic acids such as fumaric acid and glutaric acid or ester-forming derivatives thereof; (3) alicyclic dicarboxylic acids such as cyclohexanedicarboxylic acid or ester-forming derivatives thereof; (4) p-oxybenzoic acid; Oxycarboxylic acids such as oxycaproic acid or their esthetics Forming derivatives, and the like.

  On the other hand, as other glycol components that can be used together with ethylene glycol and branched aliphatic glycol and / or alicyclic glycol, for example, 1,3-propanediol, 1,4-butanediol, pentanediol, hexane Examples include aliphatic glycols such as diols, aromatic glycols such as bisphenol A and bisphenol S, and ethylene oxide adducts thereof, diethylene glycol, and triethylene glycol.

  Furthermore, a polyfunctional compound such as trimellitic acid, trimesic acid, and trimethylolpropane can be further copolymerized with the copolymerized polyester as necessary.

  Examples of the catalyst used for producing the copolymer polyester include alkaline earth metal compounds, manganese compounds, cobalt compounds, aluminum compounds, antimony compounds, titanium compounds, titanium / silicon composite oxides, and germanium compounds. . Among these, titanium compounds, antimony compounds, and germanium compounds are preferable from the viewpoint of catalytic activity.

  When producing the copolymer polyester, it is preferable to add a phosphorus compound as a heat stabilizer. As said phosphorus compound, phosphoric acid, phosphorous acid, etc. are preferable, for example.

  In the molding polyester film of the present invention, the copolymerized polyester may be used as a film raw material as it is, or a copolymerized polyester having a large amount of copolymerized components may be blended with a homopolyester to adjust the amount of copolymerized components. Absent. The latter method is preferable from the viewpoint of heat resistance.

  Moreover, it is preferable from the point of a moldability to blend 2 or more types of the said copolyester, and to use as a raw material of the polyester film for shaping | molding of this invention. Among these, a mixed polymer obtained by blending polyneopentene terephthalate and / or polycyclohexanedimethylene terephthalate with polyethylene terephthalate is particularly preferable from the viewpoint of flexibility and moldability.

  The melting point of the polyester base film is preferably 220 to 245 ° C. from the viewpoint of heat resistance and moldability. Here, the melting point is an endothermic peak temperature at the time of melting, which is detected at the time of primary temperature rise in so-called differential scanning calorimetry (DSC). The DSC was measured using a differential scanning calorimeter (DuPont, V4.OB2000 type) at a heating rate of 20 ° C./min. The lower limit of the melting point is more preferably 225 ° C, particularly preferably 230 ° C. If the melting point is less than 220 ° C, the heat resistance tends to deteriorate. Therefore, it may become a problem when exposed to high temperature during molding or use of a molded product.

  The melting point should be higher from the viewpoint of heat resistance, but when a polyethylene terephthalate unit is the main component, it is difficult to ensure transparency with a film having a melting point exceeding 245 ° C. in order to ensure high transparency and flexibility. . Therefore, it is important to lower the melting point by adjusting the ratio of the copolymer component of the copolymer polyester, and the upper limit of the melting point of the copolymer polyester is preferably 245 ° C. Furthermore, when it is necessary to increase transparency, the upper limit of the melting point of the copolyester is set to 240 ° C.

  In order to satisfy these, for example, it is preferable to melt and mix a high melting point polyester (such as PET) and a low melting point copolymer polyester. By forming a film using the melt blending method, it achieves transparency and high melting point (heat resistance) while maintaining the same level of rigidity as when only copolyester is used. When used, it is possible to achieve moderate rigidity and a practically no melting point (heat resistance) while maintaining high transparency.

  Further, it is preferable to form irregularities on the film surface in order to improve handling properties such as slipperiness and winding property of the film. As a method for forming irregularities on the film surface, a method of incorporating particles in the film is generally used.

  Examples of the particles include known internal particles having an average particle diameter of 0.01 to 10 μm, external particles such as inorganic particles and / or organic particles. When particles having an average particle diameter exceeding 10 μm are used, defects in the film are liable to occur and the design properties tend to deteriorate. On the other hand, in the case of particles having an average particle diameter of less than 0.01 μm, handling properties such as film slipperiness and winding property tend to be lowered.

  The average particle size of the particles is taken by taking a plurality of photographs of at least 200 particles by electron microscopy, tracing the outline of the particles on an OHP film, and converting the trace image to an equivalent circle diameter with an image analyzer. To calculate. When the particles are contained in the coating layer, the average particle diameter of the particles is measured by the same method.

  Examples of the external particles include inorganic particles such as wet and dry silica, colloidal silica, aluminum silicate, titanium oxide, calcium carbonate, calcium phosphate, barium sulfate, alumina, mica, kaolin, clay, hydroxyapatite, and styrene, silicone, acrylic acids. The organic particle etc. which use these as a structural component can be used. Among these, inorganic particles such as dry, wet and dry colloidal silica and alumina, and organic particles containing styrene, silicone, acrylic acid, methacrylic acid, polyester, divinylbenzene and the like as constituent components are preferably used. Two or more of these internal particles, inorganic particles and / or organic particles may be used in combination as long as the properties are not impaired.

  Furthermore, the content of the particles in the film is preferably in the range of 0.001 to 10% by mass. When the amount is less than 0.001% by mass, the handling property is likely to be deteriorated, for example, the slipperiness of the film is deteriorated or winding becomes difficult. On the other hand, if it exceeds 10% by mass, it tends to cause coarse protrusions and deterioration of film forming properties.

  The polyester film for molding of the present invention is preferably an unstretched film for applications that require severe moldability. From the viewpoint of heat resistance and dimensional stability, a biaxially stretched polyester film is preferred. Such a biaxial stretching method may be either simultaneous biaxial stretching or sequential biaxial stretching.

  The polyester film for molding of the present invention can be made into a laminated structure by a known method using different types of polyester. The form of such a laminated film is not particularly limited. For example, a laminated form of a two-layer structure of A / B, a three-layer structure of B / A / B, and a three-layer structure of C / A / B. Is mentioned.

  The method for producing the polyester film for molding of the present invention is not particularly limited. For example, after drying the polyester as necessary, the polyester film is supplied to a known melt extruder, extruded from a slit-shaped die into a sheet, An example is a method in which the unstretched sheet is biaxially stretched after being brought into close contact with the casting drum by a method such as application, solidified by cooling and obtaining an unstretched sheet.

  Such a stretching method may be either simultaneous biaxial stretching or sequential biaxial stretching. In short, the unstretched sheet is stretched and heat-treated in the longitudinal direction (MD) and the width direction (TD) of the film, and the intended surface. A method of obtaining a biaxially stretched film having an internal orientation degree is employed. Among these methods, in terms of film quality, the MD / TD method in which the film is stretched in the longitudinal direction and then stretched in the width direction, or the TD / MD method in which the film is stretched in the width direction and then stretched in the longitudinal direction. An axial stretching method and a simultaneous biaxial stretching method in which the longitudinal direction and the width direction are stretched almost simultaneously are desirable. Furthermore, if necessary, a multistage stretching method in which stretching in the same direction is performed in multiple stages may be used.

  The film stretching ratio when biaxially stretching is preferably 1.6 to 4.2 times in the longitudinal direction and the width direction, particularly preferably 1.7 to 4.0 times. In this case, the stretching ratio in the longitudinal direction and the width direction may be either larger or the same ratio.

  In the molding polyester film of the present invention, (1) a copolymer polyester composed of terephthalic acid, ethylene glycol and neopentyl glycol, or (2) a copolymer polyester composed of terephthalic acid, ethylene glycol and 1,4-cyclohexanedimethanol. When used, in order that the stress at 100% elongation in the longitudinal direction and the width direction is 180 to 1000 MPa at 25 ° C. and 1 to 100 MPa at 100 ° C., the stretching ratio in the longitudinal direction is 2.8 to 4.0 times. The stretching ratio in the width direction is preferably 3.0 to 4.5 times.

  The stretching conditions for producing the molding polyester film of the present invention are not particularly limited. However, in order to satisfy the range of stress at 100% elongation at 25 ° C. and 100 ° C. defined in the present invention, it is preferable to adopt the following conditions, for example.

  In the longitudinal stretching, the stretching temperature is preferably 50 to 110 ° C. and the stretching ratio is preferably 1.5 to 4.0 times so that the subsequent lateral stretching can be performed smoothly.

  In transverse stretching, stress at 100% elongation in the longitudinal direction and the width direction is particularly important because the stress at 25 ° C. is 180 to 1000 MPa and 100 ° C. is 1 to 100 MPa.

  Usually, when stretching the polyethylene terephthalate, if the stretching temperature is lower than the appropriate conditions, the yield stress increases rapidly at the beginning of the lateral stretching, and therefore stretching cannot be performed. Moreover, even if it can extend | stretch, since thickness and a draw ratio become easy to become nonuniform, it is unpreferable.

  In addition, when the stretching temperature is higher than appropriate conditions, the initial stress is low, but the stress does not increase even when the stretch ratio is high. Therefore, the film has a small stress at 100% elongation at 25 ° C. Therefore, by taking the optimum stretching temperature, a highly oriented film can be obtained while ensuring stretchability.

  However, when the copolymerized polyester contains 1 to 40 mol% of a copolymer component, the stretching stress rapidly decreases as the stretching temperature is increased so as to eliminate the yield stress. In particular, since the stress does not increase even in the latter half of the stretching, the orientation does not increase and the stress at 100% elongation at 25 ° C. decreases.

  Such a phenomenon is likely to occur when the thickness of the film is 60 to 500 μm, and is particularly noticeable in a film having a thickness of 100 to 300 μm. Therefore, for example, in the case of a film using polyester copolymerized with neopentyl glycol or 1,4-cyclohexanedimethanol, the stretching temperature in the transverse direction is preferably set as follows.

  First, the preheating temperature is 90 to 120 ° C., the stretching temperature in the first half of the transverse stretching is 5 to 25 ° C. higher than the preheating temperature, and the stretching temperature in the latter half of the transverse stretching is 15 than the stretching temperature in the first half. It is preferable to lower by -40 ° C. By adopting such conditions, the first half of the transverse stretching is easy to stretch because the yield stress is small, and the second half is easily oriented. In addition, it is preferable that the draw ratio of a horizontal direction shall be 2.5 to 5.0 times. As a result, it is possible to obtain a film in which the stress at 100% elongation in the longitudinal direction and the width direction satisfies 180 to 1000 MPa at 25 ° C. and 1 to 100 MPa at 100 ° C.

  Furthermore, the film is heat-treated after biaxial stretching, and this heat treatment can be performed by a conventionally known method such as in an oven or on a heated roll. Further, the heat treatment temperature and the heat treatment time can be arbitrarily set according to the required level of heat shrinkage. The heat treatment temperature is preferably in the range of 120 to 245 ° C, particularly preferably 150 to 230 ° C. The heat treatment time is preferably 1 to 60 seconds. In addition, you may perform this heat processing, relaxing a film to the longitudinal direction and / or the width direction.

  In order to reduce the thermal shrinkage in the longitudinal direction and the transverse direction at 150 ° C. of the film, it is preferable to increase the heat treatment temperature, lengthen the heat treatment time, and perform relaxation treatment. However, the method of lengthening the heat treatment time by lengthening the line is difficult due to equipment limitations. Further, the method of slowing the film feed rate and lengthening the heat treatment time has a problem that the productivity is lowered.

  In order to set the heat shrinkage rate in the longitudinal direction and the width direction at 150 ° C. to 6.0% or less, the heat treatment temperature is preferably 200 to 220 ° C. and relaxed at a relaxation rate of 1 to 8%. Furthermore, re-stretching may be performed once or more in each direction, and then heat treatment may be performed.

  In the present invention, it is important that the intrinsic viscosity of the molding polyester film is 0.58 dl / g or more, and more preferably 0.60 dl / g or more. When the intrinsic viscosity is less than 0.58 dl / g, the degree of deformation at the time of molding is high, and when the molding speed is increased, the breaking frequency of the base film for molding tends to increase. The upper limit of the intrinsic viscosity is preferably 1.0 dl / g or less from the viewpoint of discharge stability during melt extrusion.

  The means for achieving the value of the intrinsic viscosity is arbitrary without limitation, but measures are taken to increase the intrinsic viscosity of the polyester resin as a raw material, to suppress the degradation of the polyester in the film production process, and to reduce the intrinsic viscosity in the process. For example, the reduction can be suppressed.

  In order to suppress the lowering of the intrinsic viscosity in the latter film production process, the moisture content in the raw material polyester resin is lowered, the extrusion temperature in the melt extrusion process is lowered, the oxygen concentration and the moisture content in the atmosphere of the melt extrusion process It is possible to list means for reducing the above. Further, as described in claim 6, it is preferable to add 0.05 to 5% by mass of an antioxidant to the raw material polyester resin to suppress the oxidative deterioration of the polyester resin in the film production process or the like. is there.

  The type of the above-mentioned antioxidant is not limited, and examples thereof include radical trap type antioxidants such as hindered phenols, secondary aromatic amines and hindered amines, phosphonites, trialkyl phosphites, dilauryl dipropionates and the like. Peroxide decomposition type antioxidant etc. are mentioned. Of these, the use of hindered phenolic antioxidants is particularly preferred.

  Examples of the hindered phenol antioxidant include 3,5-di-t-butyl-4-hydroxy-toluene, n-octadecyl-β- (4′-hydroxy-3 ′, 5′-di-t- Butylphenyl) propionate, tetrakis [methylene-3- (3 ′, 5′-di-t-butyl-4′-hydroxyphenyl) propionate] methane, 1,3,5-trimethyl-2,4,6 ′ Tris (3,5-di-t-butyl-4-hydroxybenzyl) benzene, calcium (3,5-di-t-butyl-4-hydroxy-benzyl-monoethyl phosphate), triethylene glycol Bis [3- (3-t-butyl-5-methyl-4-hydroxyphenyl) propionate], penterisrityl-tetrakis [3- (3,5-di-t-butylanilino -1,3,5-triazine, 3,9-bis [1,1-dimethyl-2- {β- (3-tert-butyl-4-hydroxy-5-methylphenyl) propionyloxy} ethyl] 2,4 , 8,10-Tetraoxaspiro [5,5] undecane, bis [3,3-bis (4′-hydroxy-3′-t-butylphenyl) butyric acid] glycol ester, triferrol, 2,2 ′ -Ethylidenebis (4,6-di-t-butylphenol), N, N'-bis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionyl] hydrazine, 2,2'-oxamidobis [Ethyl-3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate], 1,1,3-tris (3 ′, 5′-di-t-butyl-4′-hydroxy Benzyl) -S-triazi -2,4,6 (1H, 3H, 5H) -trione, 1,3,5-tris (4-tert-butyl-3-hydroxy-2,6-dimethylbenzyl) isocyanurate, 3,5-di -T-butyl-4-hydroxyhydrocinnamic ahydr triester with-1,3,5-tris (2-hydroxyethyl) -S-triazine-2,4,6 (1H, 3H, 5H), N, N-hexamethylene bis (3,5-di-t-butyl-4-hydroxy-hydrocinnamide) and the like can be mentioned.

  The hindered phenol-based antioxidant is preferably contained in an amount of 0.05 to 5% by mass with respect to the polyester resin composition. The lower limit of the content of the antioxidant is particularly preferably 0.1% by mass from the viewpoint of thermal deterioration and heat aging resistance. On the other hand, the upper limit of the antioxidant is particularly preferably 4% by mass from the viewpoint of deterioration of the product appearance accompanying bleeding out. When the amount of the hindered phenol-based antioxidant exceeds 5% by mass, the antioxidant is bled out on the film surface, so that the appearance of the product tends to be impaired. On the other hand, when the antioxidant is less than 0.05% by mass, thermal deterioration such as foaming and heat aging resistance tend to be reduced during extrusion or molding.

  In addition, the said hindered phenolic antioxidant may be one type, and may be used together 2 or more types. Furthermore, by using the hindered phenol-based antioxidant in combination with another antioxidant, the heat aging resistance, the residence stability, and the product appearance can be further improved. Examples of other antioxidants include sulfur-based antioxidants, phosphorus-based antioxidants, and amine-based antioxidants.

  The polyester film for molding of the present invention needs to be formed by laminating a printability improving layer containing an adhesive property modifying resin on at least one surface of the base material. As a result, the adhesion to UV ink and solvent ink can be improved, and the finish and durability of printing can be improved.

  In the present invention, the composition and the laminating method thereof are not limited as long as the printing improvement layer has a function of improving the adhesion between the polyester film for molding the base material and the printing ink. However, the printability improving layer is made of at least one resin selected from the group consisting of polyester resin, polyurethane resin, acrylic resin, amino resin, epoxy resin, and oxazoline resin, and is formed by an in-line coating method. It is a preferred embodiment. The structure of the resin is not limited, but is preferably non-crystalline or low-crystalline, and may be either a commercially available product or a custom-made product having a specific composition. In addition, there is no problem with the classification of non-crosslinked products or crosslinked products. There is no problem with the type of crosslinking agent.

  The printability improving layer containing the above-mentioned adhesive property-modified resin is improved by the in-line coating method to improve the adhesion property with ink and the adhesion durability between ink and film. Moreover, it is excellent in economic efficiency and is suitable.

  In the present invention, it is a preferred embodiment that the water resistance value of the printability improving layer is 90% or more. 95% or more is more preferable. When the water resistance is less than 90%, the adhesion under wet conditions becomes poor when an ink layer is formed on the surface of the printability improving layer. The method for imparting the properties is not limited, but a preferred embodiment is made of a resin obtained by graft-modifying a hydrophobic copolymerized polyester resin with an unsaturated bond-containing monomer.

  The resin (polyester-based graft copolymer) obtained by graft-modifying the hydrophobic copolymerized polyester resin with an unsaturated bond-containing monomer will be described in detail.

  The “grafting” of the polyester-based graft copolymer in the present invention is to introduce a branched polymer composed of a polymer different from the main chain into the main chain of the main polymer. Graft polymerization is generally carried out by reacting at least one radical polymerizable monomer using a radical initiator in a state where a hydrophobic copolyester resin is dissolved in an organic solvent.

  The reaction product after completion of the grafting reaction includes a graft copolymer of a desired hydrophobic copolymerized polyester resin and a radically polymerizable monomer, a hydrophobic copolymerized polyester resin not subjected to grafting, and a hydrophobic polymer. It also contains a radical polymerizable monomer that has not been grafted to the copolymerizable polyester resin. The polyester-based graft copolymer in the present invention is not limited to the above-mentioned polyester-based graft copolymer, and in addition to this, a hydrophobic copolymerized polyester resin that has not been grafted, and a radically polymerizable monomer that has not been grafted. A reaction mixture including a monomer and the like is also included.

In the present invention, the acid value of a reaction product obtained by graft polymerization of a radically polymerizable monomer to a hydrophobic copolyester resin is preferably 600 eq / 10 ⁶ g or more. More preferably, the acid value of the reactant is 1200 eq / 10 ⁶ g or more. When the acid value of the reaction product is less than 600 eq / 10 ⁶ g, it cannot be said that the adhesion with the print layer applied to the printability improving layer is sufficient.

  The mass ratio of the desired hydrophobic copolymerized polyester resin and the radical polymerizable monomer suitable for the purpose of the present invention is preferably in the range of polyester / radical polymerizable monomer = 40/60 to 95/5, The range is desirably 55/45 to 93/7, and most desirably 60/40 to 90/10.

  When the mass ratio of the hydrophobic copolymerized polyester resin is less than 40% by mass, the excellent adhesion of the polyester resin cannot be exhibited. On the other hand, when the mass ratio of the hydrophobic copolyester resin is larger than 95% by mass, blocking, which is a defect of the polyester resin, easily occurs.

  The graft polymerization reaction product of the present invention is in the form of an organic solvent solution or dispersion or an aqueous solvent solution or dispersion. In particular, a dispersion of an aqueous solvent, that is, a form of a water-dispersed resin is preferable in terms of working environment and applicability. In order to obtain such a water-dispersed resin, a radically polymerizable monomer containing a hydrophilic radically polymerizable monomer is usually graft-polymerized to the hydrophobic copolymerized polyester resin in an organic solvent. This is achieved by adding water and distilling off the organic solvent.

  The water-dispersed resin in the present invention has an average particle diameter measured by a laser light scattering method of 500 nm or less and exhibits a translucent or milky white appearance. By adjusting the polymerization method, water-dispersed resins with various particle sizes can be obtained. The particle size is suitably 10 to 500 nm, and is preferably 400 nm or less, more preferably 300 nm or less in terms of dispersion stability. . When the average particle diameter exceeds 500 nm, the gloss of the coating film surface is lowered, the transparency of the coating is lowered, and when it is less than 10 nm, the water resistance which is the object of the present invention is lowered, which is not preferable.

  The hydrophilic radical polymerizable monomer used for the polymerization of the water-dispersed resin in the present invention means a radical polymerizable monomer having a hydrophilic group or a group that can be changed to a hydrophilic group later. Examples of the radical polymerizable monomer having a hydrophilic group include a radical polymerizable monomer containing a carboxyl group, a hydroxyl group, a phosphoric acid group, a phosphorous acid group, a sulfonic acid group, an amide group, a quaternary ammonium base and the like. be able to.

  On the other hand, examples of the radical polymerizable monomer having a group that can be changed to a hydrophilic group include radical polymerizable monomers containing an acid anhydride group, a glycidyl group, a chloro group, and the like. Among these, from the viewpoint of water dispersibility, a carboxyl group is preferable, and a radical polymerizable monomer having a carboxyl group or a group capable of generating a carboxyl group is preferable.

  The glass transition temperature of the graft copolymer is not particularly limited, but is preferably 20 ° C. or higher, more preferably 40 ° C. or higher, from the viewpoint of adhesion (high heat and humidity resistance) in a high temperature and high humidity environment.

  In the present invention, the hydrophobic copolyester resin needs to be essentially water-insoluble which does not inherently disperse or dissolve in water. When a polyester resin that is dispersed or dissolved in water is used for graft polymerization, adhesion and water resistance deteriorate.

  The composition of the dicarboxylic acid component of this hydrophobic copolyester resin is as follows: aromatic dicarboxylic acid 60 to 99.5 mol%, aliphatic dicarboxylic acid and / or alicyclic dicarboxylic acid 0 to 40 mol%, polymerizable unsaturated dicarboxylic acid. It is preferable that it is 0.5-10 mol% of dicarboxylic acid containing a heavy bond. When the aromatic dicarboxylic acid is less than 60 mol%, or when the aliphatic dicarboxylic acid and / or alicyclic dicarboxylic acid exceeds 40 mol%, the adhesive strength is lowered.

  Moreover, when the dicarboxylic acid containing a polymerizable unsaturated double bond is less than 0.5 mol%, it becomes difficult to carry out efficient grafting of the radical polymerizable monomer to the polyester resin. In the case of exceeding the viscosity, the viscosity is increased too much in the later stage of the grafting reaction, and the uniform progress of the reaction is hindered. More preferably, the aromatic dicarboxylic acid is 70 to 98 mol%, the aliphatic dicarboxylic acid and / or the alicyclic dicarboxylic acid is 0 to 30 mol%, and the dicarboxylic acid containing a polymerizable unsaturated double bond is 2 to 7 mol%. It is.

  Examples of the aromatic dicarboxylic acid include terephthalic acid, isophthalic acid, orthophthalic acid, naphthalene dicarboxylic acid, and biphenyl dicarboxylic acid. It is preferable not to use a hydrophilic group-containing dicarboxylic acid such as 5-sodium sulfoisophthalic acid from the viewpoint that the water resistance which is the object of the present invention is lowered.

  Examples of the aliphatic dicarboxylic acid include succinic acid, adipic acid, azelaic acid, sebacic acid, dodecanedioic acid, and dimer acid. Examples of the alicyclic dicarboxylic acid include 1,4-cyclohexanedicarboxylic acid. 1,3-cyclohexanedicarboxylic acid, 1,2-cyclohexanedicarboxylic acid and acid anhydrides thereof.

  Examples of dicarboxylic acids containing polymerizable unsaturated double bonds include α, β-unsaturated dicarboxylic acids such as fumaric acid, maleic acid, maleic anhydride, itaconic acid, citraconic acid, unsaturated double bonds As examples of the alicyclic dicarboxylic acid containing 2,5-norbornene dicarboxylic acid anhydride and tetrahydrophthalic anhydride can be given. Of these, fumaric acid, maleic acid and 2,5-norbornene dicarboxylic acid are preferred from the viewpoint of polymerizability.

  On the other hand, the glycol component is composed of an aliphatic glycol having 2 to 10 carbon atoms and / or an alicyclic glycol having 6 to 12 carbon atoms and / or an ether bond-containing glycol. For example, ethylene glycol, 1,2-propylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, neopentyl glycol, 1,6-hexanediol, 3-methyl-1 , 5-pentanediol, 1,9-nonanediol, 2-ethyl-2-butylpropanediol, and examples of the alicyclic glycol having 6 to 12 carbon atoms include 1,4-cyclohexanedimethanol. Can be mentioned.

  Examples of the ether bond-containing glycol include diethylene glycol, triethylene glycol, dipropylene glycol, and glycols obtained by adding ethylene oxide or propylene oxide to two phenolic hydroxyl groups of bisphenols, such as 2,2- Bis (4-hydroxyethoxyphenyl) propane can be mentioned. Polyethylene glycol, polypropylene glycol, and polytetramethylene glycol can also be used as necessary.

  In the copolymerized polyester resin used in the present invention, 0 to 5 mol% of a tri- or higher functional polycarboxylic acid and / or polyol can be copolymerized. Trimellitic anhydride, pyromellitic anhydride, benzophenone tetracarboxylic anhydride, trimesic acid, ethylene glycol bis (anhydro trimellitate), glycerol tris (anhydro trimellitate) are used. On the other hand, as the trifunctional or higher functional polyol, for example, glycerin, trimethylolethane, trimethylolpropane, and pentaerythritol are used. The tri- or higher functional polycarboxylic acid and / or polyol is copolymerized in the range of 0 to 5 mol%, preferably 0 to 3 mol%, more than 5 mol% with respect to the total acid component or the total glycol component. And gelation during polymerization tends to occur, which is not preferable.

  The hydrophobic copolyester resin preferably has a weight average molecular weight in the range of 5,000 to 50,000. When the weight average molecular weight is less than 5,000, the adhesive strength is lowered. On the contrary, when the weight average molecular weight exceeds 50,000, problems such as gelation at the time of polymerization occur.

  Examples of the polymerizable unsaturated monomer used in the present invention include (1) fumaric acid, monoethyl fumarate, diethyl fumarate, monoester or diester of fumaric acid such as dibutyl fumarate, and (2) maleic acid and its Anhydrides, monoesters or diesters of maleic acid such as monoethyl maleate, diethyl maleate, dibutyl maleate, (3) Itaconic acid and its anhydride, monoesters or diesters of itaconic acid, (4) maleimides such as phenylmaleimide (5) Styrene derivatives such as styrene, α-methyl styrene, t-butyl styrene, chloromethyl styrene, and other examples include vinyl toluene and divinyl benzene.

  Examples of the acrylic polymerizable monomer include alkyl acrylate and alkyl methacrylate (wherein the alkyl group is methyl group, ethyl group, N-propyl group, isopropyl group, N-butyl group, isobutyl group, t- Butyl group, 2-ethylhexyl group, cyclohexyl group, phenyl group, benzyl group, phenylethyl group, etc.); hydroxy-containing such as 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl acrylate, 2-hydroxypropyl methacrylate Acrylic monomer; acrylamide, methacrylamide, N-methyl methacrylamide, N-methyl acrylamide, N-methylol acrylamide, N-methylol methacrylamide, N, N-dimethylol acrylamide, N-meth Amide group-containing acrylic monomers such as cymethylacrylamide, N-methoxymethylmethacrylamide and N-phenylacrylamide; Amino group-containing acrylic monomers such as N, N-diethylaminoethyl acrylate and N, N-diethylaminoethyl methacrylate; Epoxy group-containing acrylic monomers such as glycidyl acrylate and glycidyl methacrylate; acrylic monomers containing carboxyl groups such as acrylic acid, methacrylic acid and their salts (sodium salt, potassium salt, ammonium salt) or salts thereof It is done. Preferred are maleic anhydride and esters thereof. The said monomer can be copolymerized using 1 type, or 2 or more types.

  The graft polymerization of the present invention is generally carried out by reacting a radical initiator and a radical polymerizable monomer mixture in a state where a hydrophobic copolyester resin is dissolved in an organic solvent. The reaction product after completion of the grafting reaction includes a graft copolymer between the hydrophobic copolymerized polyester resin and the radical polymerizable monomer mixture, a hydrophobic copolymerized polyester resin that has not undergone grafting, and a hydrophobic polymer. Although the radical polymer which was not grafted to the copolyester resin is also contained, the graft polymer in the present invention includes all of them.

  Examples of the graft polymerization initiator used in the present invention include organic peroxides and organic azo compounds known to those skilled in the art.

  Examples of the organic peroxide include benzoyl peroxide, t-butyl peroxypivalate, and examples of the organic azo compound include 2,2′-azobisisobutyronitrile, 2,2′-azobis (2, 4-dimethyl pareronitrile).

  The amount of the polymerization initiator used for graft polymerization is at least 0.2% by mass, preferably 0.5% by mass or more, based on the radical polymerizable monomer.

  In addition to the polymerization initiator, a chain transfer agent for adjusting the chain length of the branched polymer, for example, octyl mercaptan, mercaptoethanol, 3-t-butyl-4-hydroxyanisole may be used as necessary. In this case, it is desirable to add in the range of 0 to 5% by mass with respect to the polymerizable monomer.

  The grafting reaction solvent used in the present invention is preferably composed of an aqueous organic solvent having a boiling point of 50 to 250 ° C. The aqueous organic solvent means a solvent having a solubility in water at 20 ° C. of at least 10 g / L or more, desirably 20 g / L or more. Those having a boiling point exceeding 250 ° C. are not suitable because the evaporation rate is extremely slow and it is difficult to sufficiently remove even by high-temperature baking of the coating film.

  Further, when the boiling point of the aqueous organic solvent is less than 50 ° C., when the grafting reaction is carried out using the solvent as a solvent, it is necessary to use an initiator that cleaves into radicals at a temperature of less than 50 ° C. Increased and undesirable.

  As the first group of aqueous organic solvents that can dissolve the copolymer polyester resin well and can dissolve the polymerizable monomer mixture containing the carboxyl group-containing polymerizable monomer and the polymer thereof relatively well, For example, esters such as ethyl acetate; ketones such as methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone; cyclic ethers such as tetrahydrofuran, dioxane and 1,3-dioxolane; ethylene glycol dimethyl ether, propylene glycol methyl ether, propylene glycol propyl ether, Glycol ethers such as ethylene glycol ethyl ether and ethylene glycol butyl ether; Carbitols such as methyl carbitol, ethyl carbitol and butyl carbitol; Tate, such as ethylene glycol ethyl ether acetate, lower esters of glycols or glycol ethers, ketones alcohols such as diacetone alcohol; dimethylformamide, dimethylacetamide, substituted amides such as N- methylpyrrolidone.

  On the other hand, a second group of aqueous organic solvents that hardly dissolve the copolyester resin but can dissolve the polymer monomer mixture containing the carboxyl group-containing polymerizable monomer and the polymer relatively well. Examples include water, lower alcohols, lower carboxylic acids, and lower amines, with alcohols having 1 to 4 carbon atoms and glycols being particularly preferred.

  When the grafting reaction is performed with a single solvent, only one kind of the first group of aqueous organic solvents can be selected. When using a mixed solvent, there are a case where a plurality of types are selected only from the first group of aqueous organic solvents, and a case where at least one type is selected from the first group of aqueous organic solvents and at least one type is added thereto from the second group of aqueous organic solvents.

  Graft polymerization reaction in both cases where the graft polymerization reaction solvent is a single solvent from the first group of aqueous organic solvents and when it is a mixed solvent consisting of each of the first group and the second group of aqueous organic solvents Can be performed.

  However, there are differences in the progress of the grafting reaction, the appearance and properties of the grafting reaction product and the aqueous dispersion derived therefrom, and a mixed solvent composed of each of the first group and the second group of aqueous organic solvents. Is preferred.

  In the solvent of the first group, the copolyester molecular chain is in a state where the chain having a large spread is extended, while in the mixed solvent of the first group / second group, it is in a state of being entangled in a string of small spread. It can be confirmed by measuring the viscosity of the copolyester in these solutions.

  It is effective for preventing gelation to adjust the dissolved state of the copolyester and to make it difficult for intermolecular crosslinking to occur. Coexistence of highly efficient grafting and gelation suppression is achieved in the latter mixed solvent system. The mass ratio of the mixed solvent of the first group / second group is more desirably in the range of 95/5 to 10/90, further desirably 90/10 to 20/80, most desirably 85/15 to 30/70. is there. The optimum mixing ratio is determined according to the solubility of the polyester used.

  The grafting reaction product according to the present invention is preferably neutralized with a basic compound, and can be easily dispersed in water by neutralization.

  As the basic compound, a compound that volatilizes at the time of forming a coating film or baking and curing with a curing agent is desirable, and ammonia, organic amines, and the like are preferable. Desirable compounds include, for example, triethylamine, N, N-diethylethanolamine, N, N-dimethylethanolamine, aminoethanolamine, N-methyl-N, N-diethanolamine, isopropylamine, iminobispropylamine, ethylamine, diethylamine , 3-ethoxypropylamine, 3-diethylaminopropylamine, sec-butylamine, propylamine, methylaminopropylamine, dimethylaminopropylamine, methyliminobispropylamine, 3-methoxypropylamine, monoethanolamine, diethanolamine, triethanol Mention may be made of amines.

  The basic compound has a pH value of the aqueous dispersion in the range of 5.0 to 9.0 by at least partial neutralization or complete neutralization, depending on the carboxyl group content contained in the grafting reaction product. It is desirable to use it. If a basic compound having a boiling point of 100 ° C. or less is used, there are few residual basic compounds in the coating film after drying, adhesion of metals and inorganic deposited films, water resistance when laminated with other materials, Excellent adhesion to hot water.

  In addition, when a basic compound of 100 ° C. or higher is used or the drying conditions are controlled, and the basic compound remains in the coated film after drying by 500 ppm or more, the transfer property of the printing ink is improved.

  In the aqueous dispersion produced according to the present invention, the weight average molecular weight of the polymer of the radical polymerizable monomer is preferably 500 to 50,000.

  Generally, it is difficult to control the weight average molecular weight of the polymer of the radical polymerizable monomer to be less than 500, the grafting efficiency is lowered, and there is a tendency that hydrophilic groups are not sufficiently imparted to the copolymer polyester. is there. In addition, the graft polymer of the radical polymerizable monomer forms a hydrated layer of dispersed particles. In order to obtain a stable dispersion by providing a sufficiently thick hydrated layer, The weight average molecular weight of the graft polymer is desirably 500 or more.

  The upper limit of the weight average molecular weight of the graft polymer of the radical polymerizable monomer is preferably 50,000 from the viewpoint of polymerizability in solution polymerization. In order to set the weight average molecular weight of the graft polymer of the radical polymerizable monomer within the range of 500 to 50,000, the initiator amount, the monomer dropping time, the polymerization time, the reaction solvent, the monomer composition, or as required The chain transfer agent and the polymerization inhibitor are preferably combined appropriately.

  In the present invention, a reaction product obtained by graft polymerization of a radically polymerizable monomer to a hydrophobic copolyester resin has a self-crosslinking property, and thus exhibits a high degree of solvent resistance. Although it does not crosslink at room temperature, it undergoes intermolecular reactions such as hydrogen abstraction by thermal radicals with heat during drying, and crosslinks without a crosslinking agent. This makes it possible for the first time to exhibit the adhesion and water resistance, which are the objects of the present invention. The crosslinkability of the coating film can be evaluated by various methods, and examples thereof include a method of measuring the insoluble fraction in a chloroform solvent that dissolves both the hydrophobic copolyester resin and the radical polymer.

  The insoluble fraction of the coating film obtained by drying at 80 ° C. or lower and heat-treating at 120 ° C. for 5 minutes is preferably 50% by mass or more, more preferably 70% by mass or more. When the insoluble content of the coating film is less than 50% by mass, not only the adhesion and water resistance are not sufficient, but also blocking occurs.

  In the present invention, the above-mentioned slipperiness improving layer is not particularly limited as long as it has a function of improving the slipperiness of the above-mentioned polyester film for molding the base material, and is optional. A preferred embodiment comprising a composition comprising a polymerized polyester resin, (d) a compound having a sulfonate group, (e) particles having an average particle size of 1.0 to 5.0 μm, and (f) a polymer wax. It is.

  The copolyester resin forming the slipperiness improving layer of the present invention is a copolyester polycondensate comprising at least one dicarboxylic acid component, at least one diol component, and an ester-forming component as constituent units. The same kind of polyester resin as the above-described printability improving layer (hereinafter sometimes referred to as a layer to be printed) may be used, or a commonly used copolyester resin may be used.

  Examples of the dicarboxylic acid component that is a constituent component of the copolyester resin include (1) terephthalic acid, isophthalic acid, 2,6-naphthalenedicarboxylic acid, 4,4′-biphenylenedicarboxylic acid, 5-sodium sulfoisophthalic acid, and the like. (2) Aliphatic dicarboxylic acids such as succinic acid, adipic acid, azelaic acid and sebacic acid, (3) Alicyclics such as 1,4-cyclohexanedicarboxylic acid and 1,2-cyclohexanedicarboxylic acid Mention may be made of unsaturated dicarboxylic acids such as dicarboxylic acids, (4) maleic acid, fumaric acid and tetrahydrophthalic acid. Of these, terephthalic acid and isophthalic acid are preferable, and other dicarboxylic acids may be added in other small amounts.

  Examples of the diol component that is the other component of the copolyester resin include (1) ethylene glycol, diethylene glycol, propylene glycol, 1,3-propanediol, 1,4-butanediol, neopentyl glycol, 1, Aliphatic diols such as 6-hexanediol and polyethylene glycol, (2) alicyclic diols such as 1,4-cyclohexanedimethal, and (3) aromatic diols such as 4,4′-bis (hydroxyethyl) bisphenol A Furthermore, bis (polyoxyethylene glycol) bisphenol ether can be mentioned. Of these, ethylene glycol and diethylene glycol are most preferable, and a small amount of other diol components may be used.

  In addition to the dicarboxylic acid component, 5-sodium sulfoisophthalic acid is preferably used in the range of 1 to 10 mol% in order to impart water dispersibility to the copolyester resin. -Sulfoisophthalic acid, 4-sulfonaphthalene-2,6 dicarboxylic acid, 5- (4-sulfophenoxy) isophthalic acid and the like can be used.

  The resin component is preferably contained in the coating layer in the range of 30 to 95% by mass. When the amount is less than 30% by mass, the film strength is insufficient, and the film easily falls off when an external force such as friction is applied. Furthermore, the particles are likely to fall off. On the other hand, when it exceeds 95% by mass, the strength as a film is improved, but the intended performance such as antistatic performance and slipperiness is hardly exhibited. Preferably it is 50-90 mass%.

The compound having a sulfonate group is a compound used for the purpose of imparting antistatic properties. For example, an unsaturated monomer having a sulfonate group (for example, sodium vinyl sulfonate, sodium methallyl sulfonate, A polymer antistatic agent comprising one or more polymers of sodium styrene sulfonate, ammonium vinyl sulfonate, potassium methacryl sulfonate, lithium styrene sulfonate, etc., and R-SO ₃ X (where R is an alkyl) A low molecular weight antistatic agent of an aromatic group having a group, an aryl group or an alkyl group, wherein X represents a metal ion (for example, Li, Na, K, etc.), an ammonium ion, an amine ion, or a phosphate ester ion) And its dimer, etc., but it has a sulfonate group with excellent heat resistance and exhibits antistatic properties. As long as the functions are not limited to the above compounds.

  Examples of the alkyl sulfonate include sodium pentane sulfonate, sodium octane sulfonate, lithium octane sulfonate, potassium octane sulfonate, and sodium tetradecyl sulfonate.

  Examples of the aryl sulfonate include sodium benzyl sulfonate, sodium toluyl sulfonate, and sodium naphthyl sulfonate. Furthermore, examples of the aromatic sulfonate having an alkyl group include alkyl (carbon number: 8 to 20) benzenesulfonic acid metal salts (for example, Li, K, Na salts) such as sodium dodecylbenzenesulfonate, and alkylnaphthalene. Examples include sodium sulfonate and sodium alkylphenyl ether disulfonate.

  The polymer antistatic agent comprising a polymer of an unsaturated monomer having a sulfonate group uses, for example, a styrene resin containing a sulfonate group component in the molecule such as polystyrene sulfonate. It is preferable.

  This polymer antistatic agent is characterized by the high hydrophilicity of its sulfonic acid component. Examples of the styrene resin containing a sulfonate group component in the molecule include homopolymers such as sodium salt, potassium salt, lithium salt, ammonium salt, and phosphonium salt of polystyrene sulfonic acid, acrylic acid ester, and methacrylic acid ester. Examples thereof include a copolymer of an acrylic monomer and a styrene sulfonic acid monomer.

  The weight average molecular weight of the polystyrene sulfonate used in the present invention is 1,000 to 150,000, preferably 10,000 to 70,000. When the molecular weight is less than 1,000, it becomes difficult to obtain water resistance of the coating film, and when it exceeds 150,000, uniform mixing with the copolymerized polyester tends to be difficult.

When the compound having a sulfonate group used in the present invention is a low molecule, the mixing ratio in each layer is preferably 0.5 to 15% by mass, particularly preferably 2 to 10% by mass. Moreover, when the compound which has a sulfonate group is a polymer | macromolecule, 5 to 50% of weight is preferable, Most preferably, it is 10 to 30 mass%. A mixture of the low molecular compound and the high molecular compound may be used. When the surface specific resistance value of the coating layer containing the compound having a sulfonate group exceeds 10 ¹³ Ω / □ under the conditions of 23 ° C. and 50% RH, when the sheet is used as a single-wafer film, Therefore, the slipperiness becomes insufficient, and the transportability such as double feeding in a high-speed printing machine tends to deteriorate.

  Furthermore, examples of the aromatic sulfonate having an alkyl group include alkyl (carbon number: 8 to 20) benzenesulfonic acid metal salts (for example, Li, K, Na salts) such as sodium dodecylbenzenesulfonate, and alkylnaphthalene. Examples include sodium sulfonate and sodium alkylphenyl ether disulfonate.

  The polymer antistatic agent comprising a polymer of an unsaturated monomer having a sulfonate group uses, for example, a styrene resin containing a sulfonate group component in the molecule such as polystyrene sulfonate. It is preferable.

  This polymer antistatic agent is characterized by the high hydrophilicity of its sulfonic acid component. Examples of the styrene resin containing a sulfonate group component in the molecule include homopolymers such as sodium salt, potassium salt, lithium salt, ammonium salt, and phosphonium salt of polystyrene sulfonic acid, acrylic acid ester, and methacrylic acid ester. Examples thereof include a copolymer of an acrylic monomer and a styrene sulfonic acid monomer.

  The weight average molecular weight of the polystyrene sulfonate used in the present invention is 1,000 to 150,000, preferably 10,000 to 70,000. When the molecular weight is less than 1,000, it becomes difficult to obtain water resistance of the coating film, and when it exceeds 150,000, uniform mixing with the copolymerized polyester tends to be difficult.

When the compound having a sulfonate group used in the present invention is a low molecule, the mixing ratio in each layer is preferably 0.5 to 15% by mass, particularly preferably 2 to 10% by mass. Moreover, when the compound which has a sulfonate group is a polymer | macromolecule, 5 to 50% of weight is preferable, Most preferably, it is 10 to 30 mass%. A mixture of the low molecular compound and the high molecular compound may be used. When the surface specific resistance value of the coating layer containing the compound having a sulfonate group exceeds 10 ¹³ Ω / □ under the conditions of 23 ° C. and 50% RH, when the sheet is used as a single-wafer film, Therefore, the slipperiness becomes insufficient, and the transportability such as double feeding in a high-speed printing machine tends to deteriorate.

  Commercially available inorganic particles and / or organic particles can be used as the particles having an average particle diameter of 1 to 5 μm. The average particle diameter is more preferably in the range of 1 to 3 μm. Examples of the inorganic particles include silica, calcium carbonate, and alumina, and examples of the organic particles include, but are not limited to, polyolefin, acrylic, styrene, urethane, polyamide, and polyester.

  Moreover, content with respect to the resin component of the said particle | grain in an improvement layer is 0.3-10 mass%, Preferably it is 0.7-5 mass%. When the average particle size is less than 1 μm or the particle content is less than 0.3% by mass, it is difficult to form appropriate irregularities on the surface of the improved layer. As a result, when it is a sheet-fed film, it is difficult for an air layer to accumulate between the films, the friction immediately after releasing the load cannot be reduced, and it becomes difficult to increase the printing speed. When the average particle diameter exceeds 10 μm, or when the particle content is 10% by mass or more, the haze of the film becomes high, the transparency is deteriorated, or the problem of the printing quality is deteriorated due to particle dropping. The machine stand is likely to be contaminated.

  It is a preferred embodiment that the above-mentioned particles are also contained in the above-mentioned printability improving layer from the viewpoint of making the improvement effect of slipperiness more remarkable.

  The polymer wax component is not particularly limited as long as it does not impair transparency, and conventionally known wax components can be used. For example, a polyethylene type, a polypropylene type, and a fatty acid type are mentioned. The weight average molecular weight of these wax components is preferably 1,000 to 10,000, more preferably 1,500 to 6,000. When the molecular weight is less than 1,000, oozing from the inside of the coating layer to the surface tends to cause transfer contamination to the printing surface, which adversely affects the ink adhesion.

  When the molecular weight exceeds 10,000, the effect of improving slipperiness becomes insufficient. Content with respect to the resin component of the wax component in a coating layer is 1-10 mass%, Preferably it is 2-8 mass%. When the content of the wax component in the coating layer with respect to the resin component is less than 1% by mass, the friction coefficient cannot be lowered sufficiently and the printing speed cannot be increased. When the content of the wax component with respect to the resin component in the coating layer exceeds 10% by mass, the loss of the wax component causes contamination of the printed surface, and further deterioration of transparency and haze.

  In the present invention, it is preferable that both the static friction coefficient and the dynamic friction coefficient when the printability improving layer and the slipperiness improving layer are overlapped are 0.5 or less.

  In a state where the coefficient of dynamic friction exceeds 0.5, the slipperiness is insufficient, and for example, a conveyance failure occurs when paper is fed on a sheet-fed printing press. Generally, the static friction coefficient shows a maximum value when the film is rubbed, and is higher than the dynamic friction coefficient. However, when the lubricant is included in at least one of the improvement layers, the coefficient of friction rises gently as the friction travels, so that the value of the static friction coefficient becomes equal to or lower than the dynamic friction coefficient. A low coefficient of static friction makes the beginning of movement during sheeting smoother. As a result, the sheet-fed printing press can improve the printing speed.

  When producing the molding polyester film of the present invention, the method of forming the above-mentioned improved layer on both sides of the polyester base film is not limited and is arbitrary, but a method carried out by a coating method is suitable. As the step of applying the coating solution in this method, a method of coating on an unstretched film and then stretching in at least one direction, a method of coating after longitudinal stretching, a method of coating on the film surface after the orientation treatment, etc. Either method is possible. Among them, when producing a polyester base film, there is a so-called in-line coating method in which the film is applied before the crystal orientation of the film is completed and then stretched in at least one direction, and then the crystal orientation of the molding polyester film is completed. This is a preferred method that can manifest the effects of the present invention more remarkably.

  The copolymer polyester resin and the compound having a sulfonate group have a difference in hydrophilicity and are easily separated, so that the coating solution is 2 seconds immediately after applying a shear rate of 1000 (1 / second) or more immediately before coating. It is preferable to carry out by a method in which the coating is applied to the substrate within 2 seconds, followed by preliminary drying at 70 ° C. or less, humidity 50% RH, and wind speed of 10 to 20 m / second for 1 to 3 seconds and then drying at 90 ° C. or more. By coating by this method, the copolymer polyester resin and the compound having a sulfonate group are uniformly dispersed, and a good surface resistance value can be obtained.

  There are no particular limitations on the heat setting conditions after coating and drying and stretching after the application and drying in the case of the in-line coating method, but the polyester-based graft copolymer that is a constituent component of the easily printable coating layer has a self-crosslinking property. In order to express the above, it is preferable to adopt a condition for increasing the amount of heat within a range in which the base film and the graft copolymer do not undergo thermal degradation. Specifically, it is 200 ° C to 250 ° C, preferably 220 ° C to 250 ° C. However, by increasing the heat setting time, sufficient self-crosslinking property can be exhibited even at a relatively low temperature.

  As a method for providing the coating layer, a conventionally used method such as a gravure coating method, a kiss coating method, a dip method, a spray coating method, a curtain coating method, an air knife coating method, a blade coating method, or a reverse roll coating method is applied. be able to

The thicknesses of the two coating layers are not particularly limited, but in the present invention, the final thickness after drying is preferably 0.05 to 1.0 μm, more preferably 0.07 to 0.5 μm, particularly preferably. Is 0.09 to 0.3 μm.
In the coating liquid of the present invention, known additives such as surfactants, antioxidants, heat stabilizers, weather stabilizers, ultraviolet absorbers, and organic lubricants are added to the extent that the effects of the present invention are not impaired. You may make it contain.

  A laminated film having a normal coating layer has inert particles in order to form irregularities on the film surface for the purpose of improving handling properties (e.g., slipperiness, winding property, blocking resistance) and scratch resistance. Contained. However, it is preferable that the polyester film for laminated molding of the present invention contains particles in the coating layer to reduce transparency, and the content of particles in the base film is preferably reduced. It is particularly preferred not to contain particles. “Substantially no particles” means that the content of main component atoms constituting the particles in the base film is below the detection limit of the fluorescent X-ray analysis method.

  In the polyester film for lamination molding of the present invention, high transparency can be obtained while having a coating layer on both sides by using a base film substantially containing no particles inside. Therefore, the brightness at the time of illumination by transmitted light is excellent, and the sharpness of characters and images when the printed surface is viewed through the film from the easy smooth surface (coating layer B / non-printed surface) side is extremely excellent.

  Further, in the present invention, the adhesion strength with the coating layer A for commonly used UV curable printing inks and solvent-based printing inks is 1 mm square in cross-cut evaluation with a grid according to JIS-K5400. The number of eyes is preferably 90% or more, more preferably 96% or more.

  If the adhesion is less than 90%, ink dropout occurs after printing, leading to deterioration in appearance and transportability. In general, offset printing makes it difficult for ink to drop off because the ink thickness is 1 μm to several μm. However, screen printing may be several μm to 10 μm or more, and the printing performance has adhesion that can be applied to screen printing ink. Necessary for transparent molding polyester film.

  The polyester film for molding of the present invention is a preferred embodiment in which the base film has a melting point of 220 to 245 ° C. Even if it is used for mold molding or insert molding in addition to the above characteristics by making the melting point range, such as when the pattern of the molded product is distorted, the surface of the molded product is rough and causes poor appearance, etc. It can suppress that what is called finishing property deteriorates. Furthermore, the melting point is more preferably 220 to 240 ° C.

  In the present invention, the light transmittance at a wavelength of 380 nm is preferably 50% or less, more preferably 35% or less, and particularly preferably 20% or less. If the light transmittance at a wavelength of 380 nm is less than 50%, the light resistance of the polyester film for molding, particularly when the printed layer is printed, may deteriorate.

  The method for reducing the light transmittance at a wavelength of 380 nm to 50% or less is arbitrary, and an ultraviolet absorber is added to at least one of the substrate, the printability improving layer, and the slipperiness improving layer in the molding polyester film. It is preferable to contain.

  The ultraviolet absorber used in the above method may be appropriately selected without limitation as long as it can impart the above-mentioned characteristics. Either inorganic or organic may be used. Examples of organic ultraviolet absorbers include benzotoazole, benzophenone, cyclic imino ester, and combinations thereof. From the viewpoint of durability, benzotoazole and cyclic imino ester are particularly preferable. When two or more kinds of ultraviolet absorbers are used in combination, ultraviolet rays having different wavelengths can be absorbed simultaneously, so that the ultraviolet absorption effect can be further improved.

  Examples of the benzotriazole ultraviolet absorber include 2- [2′-hydroxy-5 ′-(methacryloyloxymethyl) phenyl] -2H-benzotriazole, 2- [2′-hydroxy-5 ′-(methacryloyloxyethyl). ) Phenyl] -2H-benzotriazole, 2- [2'-hydroxy-5 '-(methacryloyloxypropyl) phenyl] -2H-benzotriazole, 2- [2'-hydroxy-5'-(methacryloyloxyhexyl) phenyl ] -2H-benzotriazole, 2- [2'-hydroxy-3'-tert-butyl-5 '-(methacryloyloxyethyl) phenyl] -2H-benzotriazole, 2- [2'-hydroxy-5'-tert -Butyl-3 '-(methacryloyloxyethyl) phenyl] -2 -Benzotriazole, 2- [2'-hydroxy-5 '-(methacryloyloxyethyl) phenyl] -5-chloro-2H-benzotriazole, 2- [2'-hydroxy-5'-(methacryloyloxyethyl) phenyl] -5-methoxy-2H-benzotriazole, 2- [2'-hydroxy-5 '-(methacryloyloxyethyl) phenyl] -5-cyano-2H-benzotriazole, 2- [2'-hydroxy-5'-( Methacryloyloxyethyl) phenyl] -5-tert-butyl-2H-benzotriazole, 2- [2'-hydroxy-5 '-(methacryloyloxyethyl) phenyl] -5-nitro-2H-benzotriazole, and the like. However, it is not particularly limited to these.

  Examples of the cyclic imino ester ultraviolet absorber include 2,2 ′-(1,4-phenylene) bis (4H-3,1-benzoxazinon-4-one), 2-methyl-3,1-benzo. Oxazin-4-one, 2-butyl-3,1-benzoxazin-4-one, 2-phenyl-3,1-benzoxazin-4-one, 2- (1- or 2-naphthyl) -3,1 -Benzoxazin-4-one, 2- (4-biphenyl) -3,1-benzoxazin-4-one, 2-p-nitrophenyl-3,1-benzoxazin-4-one, 2-m-nitro Phenyl-3,1-benzoxazin-4-one, 2-p-benzoylphenyl-3,1-benzoxazin-4-one, 2-p-methoxyphenyl-3,1-benzoxazin-4-one, 2 -O-metoki Phenyl-3,1-benzoxazin-4-one, 2-cyclohexyl-3,1-benzoxazin-4-one, 2-p- (or m-) phthalimidophenyl-3,1-benzoxazin-4-one 2,2 '-(1,4-phenylene) bis (4H-3,1-benzoxazinon-4-one) 2,2'-bis (3,1-benzoxazin-4-one), 2, 2'-ethylenebis (3,1-benzoxazin-4-one), 2,2'-tetramethylenebis (3,1-benzoxazin-4-one), 2,2'-decamethylenebis (3 1-benzoxazin-4-one), 2,2′-p-phenylenebis (3,1-benzoxazin-4-one), 2,2′-m-phenylenebis (3,1-benzoxazine-4 -On), 2,2 '-(4 4'-diphenylene) bis (3,1-benzoxazin-4-one), 2,2 '-(2,6- or 1,5-naphthalene) bis (3,1-benzoxazin-4-one), 2,2 '-(2-methyl-p-phenylene) bis (3,1-benzoxazin-4-one), 2,2'-(2-nitro-p-phenylene) bis (3,1-benzoxazine -4-one), 2,2 '-(2-chloro-p-phenylene) bis (3,1-benzoxazin-4-one), 2,2'-(1,4-cyclohexylene) bis (3 , 1-Benzoxazin-4-one) 1,3,5-tri (3,1-benzoxazin-4-one-2-yl) benzene, 1,3,5-tri (3,1-benzoxazine- 4-On-2-yl) naphthalene and 2,4,6-tri (3,1- Nzookisajin-4-one-2-yl) naphthalene. 2,8-dimethyl-4H, 6H-benzo (1,2-d; 5,4-d ') bis- (1,3) -oxazine-4,6-dione, 2,7-dimethyl-4H, 9H -Benzo (1,2-d; 5,4-d ') bis- (1,3) -oxazine-4,9-dione, 2,8-diphenyl-4H, 8H-benzo (1,2-d; 5,4-d ') bis- (1,3) -oxazine-4,6-dione, 2,7-diphenyl-4H, 9H-benzo (1,2-d; 5,4-d') bis- (1,3) -Oxazine-4,6-dione, 6,6'-bis (2-methyl-4H, 3,1-benzoxazin-4-one), 6,6'-bis (2-ethyl- 4H, 3,1-benzoxazin-4-one), 6,6′-bis (2-phenyl-4H, 3,1-benzoxazin-4-one), 6, '-Methylenebis (2-methyl-4H, 3,1-benzoxazin-4-one), 6,6'-methylenebis (2-phenyl-4H, 3,1-benzoxazin-4-one), 6,6 '-Ethylenebis (2-methyl-4H, 3,1-benzoxazin-4-one), 6,6'-ethylenebis (2-phenyl-4H, 3,1-benzoxazin-4-one), 6 , 6'-Butylenebis (2-methyl-4H, 3,1-benzoxazin-4-one), 6,6'-Butylenebis (2-phenyl-4H, 3,1-benzoxazin-4-one), 6 , 6'-oxybis (2-methyl-4H, 3,1-benzoxazin-4-one), 6,6'-oxybis (2-phenyl-4H, 3,1-benzoxazin-4-one), 6 , 6'-sulfonylbis ( -Methyl-4H, 3,1-benzoxazin-4-one), 6,6'-sulfonylbis (2-phenyl-4H, 3,1-benzoxazin-4-one), 6,6'-carbonylbis (2-methyl-4H, 3,1-benzoxazin-4-one), 6,6'-carbonylbis (2-phenyl-4H, 3,1-benzoxazin-4-one), 7,7'- Methylenebis (2-methyl-4H, 3,1-benzoxazin-4-one), 7,7'-methylenebis (2-phenyl-4H, 3,1-benzoxazin-4-one), 7,7'- Bis (2-methyl-4H, 3,1-benzoxazin-4-one), 7,7'-ethylenebis (2-methyl-4H, 3,1-benzoxazin-4-one), 7,7 ' -Oxybis (2-methyl-4H, 3,1- Benzoxazin-4-one), 7,7'-sulfonylbis (2-methyl-4H, 3,1-benzoxazin-4-one), 7,7'-carbonylbis (2-methyl-4H, 3 1-benzoxazin-4-one), 6,7'-bis (2-methyl-4H, 3,1-benzoxazin-4-one), 6,7'-bis (2-phenyl-4H, 3 1-benzoxazin-4-one), 6,7'-methylenebis (2-methyl-4H, 3,1-benzoxazin-4-one), and 6,7'-methylenebis (2-phenyl-4H, 3 , 1-benzoxazin-4-one) and the like, but is not particularly limited thereto.

  When blending the organic ultraviolet absorber in the base film, it is exposed to a high temperature in the extrusion process, so the ultraviolet absorber uses a UV absorber having a decomposition start temperature of 290 ° C. or more at the time of film formation. It is preferable in order to reduce contamination. If an ultraviolet absorber having a decomposition start temperature of 290 ° C. or lower is used, the decomposed product of the ultraviolet absorber adheres to the roll group of the manufacturing apparatus during film formation, and may reattach to the film or be damaged. Since it becomes an optical fault, it is not preferable.

  Examples of inorganic ultraviolet absorbers include ultrafine particles of metal oxides such as cerium oxide, zinc oxide, and titanium oxide.

  As another method for reducing the light transmittance at a wavelength of 380 nm to 50% or less, a method of using a compound which forms a polyester, such as naphthalenedicarboxylic acid, having absorption in this wavelength region, as a copolymerization component of the polyester is given. be able to.

  The molding polyester film of the present invention is particularly preferably used for molding applications. The polyester film for molding is used by applying heat or pressure to deform it. As the molding means, a mold molding method and an insert molding method are particularly suitable. The molded body thus molded is used for molded members such as household nameplates, automobile nameplates, dummy cans, building materials, decorative plates, decorative steel plates, transfer sheets and the like.

  Hereinafter, the present invention will be described in detail by way of examples. The film properties obtained in each example were measured and evaluated by the following methods.

(1) Intrinsic viscosity 0.1 g of the chip sample was precisely weighed and dissolved in 25 ml of a mixed solvent of phenol / tetrachloroethane = 6/4 (mass ratio), and measured at 30 ° C. using an Ostwald viscometer. In addition, the measurement was performed 3 times and the average value was calculated | required.

(2) Thickness unevenness A continuous tape-like sample having a length of 3 m in the transverse stretching direction and a length of 5 cm in the longitudinal stretching direction is taken up, and the thickness of the film is measured with a continuous film thickness measuring machine (manufactured by Anritsu Corporation). To record. From the chart, the maximum value (dmax), minimum value (dmin), and average value (d) of the thickness were obtained, and the thickness unevenness (%) was calculated by the following formula. In addition, the measurement was performed 3 times and the average value was calculated | required. Moreover, when the length of a horizontal extending direction is less than 3 m, it joins and performs. The connecting part is deleted from the data.
Unevenness of thickness (%) = ((dmax−dmin) / d) × 100

(3) Haze Based on JIS-K7136, it measured using the haze meter (Nippon Denshoku Industries Co., Ltd. make, 300A). In addition, the measurement was performed twice and the average value was calculated | required.

(4) Film Thickness Using a millitron, a total of 15 points were measured, 5 points per sheet, and the average value was determined.

(5) Stress at 100% elongation, elongation at break With respect to the longitudinal direction and width direction of the biaxially stretched film, a sample was cut into a strip shape having a length of 180 mm and a width of 10 mm, respectively, with a single-blade razor, and the sample was pulled. The sample was pulled using Toyo Seiki Co., Ltd., and the stress at 100% elongation (MPa) and elongation at break (%) in each direction were determined from the obtained load-strain curve.

  The measurement was performed in an atmosphere of 25 ° C. under the conditions of an initial length of 40 mm, a distance between chucks of 100 mm, a crosshead speed of 100 mm / min, a recorder chart speed of 200 mm / min, and a load cell of 25 kgf. The measurement was performed 10 times and the average value was used.

  In addition, a tensile test was performed under the same conditions as described above even in an atmosphere at 100 ° C. At this time, the sample was held for 30 seconds in an atmosphere at 100 ° C. and then measured. The measurement was performed 10 times and the average value was used.

(6) Thermal contraction rate at 150 ° C. A strip sample having a length of 250 mm and a width of 20 mm is cut out in the longitudinal direction and the width direction of the film, respectively. Two marks are marked at intervals of 200 mm in the length direction of each sample, and the distance A between the two marks is measured under a constant tension (tension in the length direction) of 5 gf. Subsequently, one side of each strip-shaped sample is hung with a clip on a basket under no load, and placed in a gear oven under an atmosphere of 150 ° C., and time is taken. After 30 minutes, the basket is removed from the gear oven and left at room temperature for 30 minutes. Next, for each sample, the distance B between the two marks is read with a gold finger in units of 0.25 mm under a constant tension of 5 gf (longitudinal tension). From the read intervals A and B, the thermal shrinkage rate at 150 ° C. of each sample is calculated by the following formula.
Thermal contraction rate (%) = ((A−B) / A) × 100

(7) Formability After printing on the film, it was heated at 130 ° C. for 5 seconds, and then press-molded at a mold temperature of 80 ° C. and a pressure holding time of 5 seconds. The obtained press-molded product was subjected to insert molding in which an ABS resin having a resin temperature of 210 ° C. was poured with an injection molding machine, and a key top having a height of 3.0 mm covered with a film was produced. Printing deviations were measured for the 10 created, and the molding state was visually observed and ranked according to the following criteria. In addition, (double-circle) and (circle) were set as the pass, and x was set as the disqualification.

A: Printing deviation is 0.1 mm or less, and the appearance is very good.
◯: The printing misalignment is 0.1 mm or more and 0.2 mm or less, and some wrinkles are seen, but it is a level that causes no problem in practical use.
X: Printing deviation exceeds 0.2 mm. Or, the film is broken. Or a big wrinkle enters and the appearance is remarkably bad.

(8) Molding operability The following mold molding was carried out, molding was performed 50 times, the ratio that could be molded without any trouble such as perforation was calculated, and ○ was passed based on the following criteria.
<Mold molding conditions>
(A) Mold shape
(a-1) Cup shape, (a-2) Diameter: 50 mmΦ, (a-3) Height: 20 mm,
(a-4) Chamfering with a radius of 0.5 mm for all surfaces,
(a-5) Clearance between male and female molds: 0.5mm
(B) Molding conditions
(b-1) Film temperature: 130 ° C. (b-2) Mold temperature: 80 ° C.
(b-3) Stroke: 50 mm, (b-4) Clamping speed: 10 cm / second,
(b-5) Holding time: 5 seconds <Criteria>
○: 95% or more △: 50% or more and less than 95% ×: less than 50%

(9) Static friction coefficient μs and dynamic friction coefficient μd
Based on JIS-C2151, the following conditions evaluated.
-Test piece for flat plate: 130mm in width and 250mm in length, using non-printing surface side-Test piece for warping: 120mm in width, using printing surface side in length of 120mm-Measuring atmosphere: 23 ° C, 50% RH
-Sled mass: 200 gf
・ Test speed: 150mm / min

(10) Surface resistivity The surface resistivity of the antistatic layer of the polyester film for molding in an atmosphere of 23 ° C. and 50% RH using a surface resistance meter (HIRESUTA MCP HT-260, manufactured by Mitsubishi Yuka Co., Ltd.) Ω / □) was measured under the following conditions.
Applied voltage: 500V
Measurement time: 10 seconds Probe used: Type HRS

(11) Ink adhesion strength In accordance with the cross-cut evaluation described in JIS-K5400, after printing the following ink on the surface to be printed (printability improving layer in the present invention), a 1 mm square is printed using a cross-cut guide. After making 100 pieces with a cutter blade, the adhesive force of the grid portion was evaluated using an adhesive tape (manufactured by Nichiban Co., Ltd., cellophane tape).

  Adhesion strength with UV curable ink is UV curable ink (manufactured by Toka Dye Co., Ltd., Best Cure 161), and 100mJ UV is applied to the coating layer surface of the film (printability improving layer in the present invention) after printing with an RI tester. Irradiated and evaluated according to the method described above. Also, using another UV curable ink (Seiko Advance Co., Ltd., UVA), the surface of the coating layer (printability improving layer in the present invention) was irradiated with 500 mJ of UV after # 300 screen printing, and according to the above method. Evaluation was performed in the same manner.

  The adhesive strength with the solvent-type ink is solvent-type ink (Toyo Ink Co., Ltd., TSP-400G), which is left to dry for 24 hours after printing on the coating layer surface of the film (printability improving layer in the present invention) with an RI tester, Evaluation was performed according to the above method. Also, using another solvent-based ink (Tetron, manufactured by Jujo Ink Co., Ltd.), the coating layer surface of the film (printability improving layer of the present invention) was left to dry for 24 hours after screen printing of # 250, and the above method was applied. Therefore, it evaluated similarly.

(12) Water resistance value An offset ink (Tea and Kei Toka Co., Ltd., Best Cure 161) was transferred onto the surface of the film with a printability improving layer by an RI tester (Meiji Seisakusho, RI-3). Next, an ink layer having a thickness of 1 μm was formed using a high-pressure mercury lamp under the conditions of an irradiation energy of 200 mJ / cm ² and an irradiation distance of 15 cm while running the film at a feeding speed of 5 m / min.

  The obtained film was placed in an autoclave containing water (Tomy Seiko Co., Ltd., SR-240), and pressure boiled at 120 ° C. for 1 hour. After the boil treatment, the autoclave was returned to normal pressure, and the film was taken out from the autoclave. The water adhering to the film surface was removed and left at room temperature for 12 hours.

The adhesion of the ink layer of the film after the boil treatment was determined by a test method according to the description in 8.5.1 of JIS-K5400. Specifically, 100 grid-like cuts reaching the base film are made using a cutter guide with a gap interval of 2 mm. Next, a cellophane adhesive tape (manufactured by Nichiban Co., Ltd., No. 405, 24 mm width) is attached to the grid-shaped cut surface and rubbed with an eraser to completely adhere. Thereafter, the cellophane adhesive tape is peeled off vertically from the film, the number of squares peeled off from the film is visually counted, and the adhesion is obtained from the following formula. In addition, what was partly peeling among the squares was also regarded as peeling, and was ranked according to the following criteria.
Adhesiveness (%) = (1−number of peeled squares / 100) × 100
<Rank of adhesion>
A: 100%, O: 99-96%, Δ: 95-80%, x: 79-0%

(13) Suitability for fountain solution Before printing with the ink, when printing on the coating layer surface (printability improving layer in the present invention) of the film with an RI tester using a solvent-type offset printing ink (manufactured by Toyo Ink Co., Ltd., TSP-400G) The film printed surface was pressed with a Molton roller dipped and moistened with 0.2 ml, 0.4 ml, and 0.6 ml of ion-exchanged water using a spoid, and then the ink was developed and checked for ink transfer failure. confirmed.

(14) Feeding stability Using a sheet-fed offset printing machine (Heidelberg, Speedmaster, 8-color printing machine), stacking sheet-size films with a size of Kikuzen (636 x 939 mm) in size, when printing speed is low The sheet feeding stability was evaluated when feeding and printing at (4,000 sheets / hour) and at high speed (8,000 sheets / hour).

(15) Print quality The print appearance of the print sample used in the feed stability evaluation was judged visually. At this time, the appearance was visually judged through the film from the back side, not from the printed surface. Judgment criteria are as follows.
(A) Clear feeling: The printed design is clear without being blocked by the base film or coating layer
To see.
(B) Printability: Color unevenness and missing due to poor transfer of printing ink

(16) Ultraviolet transmittance The light transmittance at a wavelength of 380 nm was measured using a double beam type spectrophotometer (manufactured by Hitachi, Ltd., U-2001).

(17) Light resistance Using the printing sample used in the paper feeding stability evaluation, the printing surface is on the back side at a position 3 cm directly below the fluorescent lamp lamp (Matsushita Electric Co., Ltd., U-type fluorescent lamp FUL9EX) in a dark box. Was installed. Subsequently, irradiation was continuously performed for 2000 hours, and the color difference (ΔE) before and after irradiation on the printed surface side was measured according to JIS-Z8730, and a case where ΔE was 0.5 or less was regarded as acceptable.

Example 1
(Preparation of hydrophobic copolyester resin)
In a stainless steel autoclave equipped with a stirrer, thermometer and partial reflux condenser, 218 parts by mass of dimethyl terephthalate, 194 parts by mass of dimethyl isophthalate, 488 parts by mass of ethylene glycol, 200 parts by mass of neopentyl glycol and tetra-N-butyl titanate 0.5 parts by mass was charged, and a transesterification reaction was performed from 160 ° C. to 220 ° C. over 4 hours. Next, 13 parts by mass of fumaric acid and 51 parts by mass of sebacic acid were added, and the temperature was raised from 200 ° C. to 220 ° C. over 1 hour to carry out an esterification reaction. Next, the temperature was raised to 255 ° C., and the reaction system was gradually depressurized, and then reacted for 1 hour 30 minutes under a reduced pressure of 0.22 mmHg to obtain a hydrophobic copolyester resin. The obtained hydrophobic copolyester was light yellow and transparent.

(Preparation of water-dispersed polyester-based graft copolymer)
In a reactor equipped with a stirrer, thermometer, refluxing device and quantitative dropping device, 75 parts by mass of hydrophobic copolymer polyester, 56 parts by mass of methyl ethyl ketone and 19 parts by mass of isopropyl alcohol are heated and stirred at 65 ° C. Dissolved. After the resin was completely dissolved, 15 parts by mass of maleic anhydride was added to the polyester solution. Subsequently, a solution prepared by dissolving 10 parts by mass of styrene and 1.5 parts by mass of azobisdimethylvaleronitrile in 12 parts by mass of methyl ethyl ketone was dropped into the polyester solution at 0.1 ml / min, and stirring was further continued for 2 hours. After sampling for analysis from the reaction solution, 5 parts by mass of methanol was added. Next, 300 parts by mass of ion-exchanged water and 15 parts by mass of triethylamine were added to the reaction solution and stirred for 1.5 hours. Thereafter, the reactor internal temperature was raised to 100 ° C., and methyl ethyl ketone, isopropyl alcohol, and excess triethylamine were distilled off to obtain a water-dispersed polyester graft copolymer. The obtained polyester-based graft copolymer was light yellow and transparent, and the glass transition temperature was 40 ° C.

(Preparation of coating solution A for printability improving layer)
A polyester graft copolymer dispersed in water so that the total solid concentration is 5% by mass in a mixed solvent of ion-exchanged water and isopropyl alcohol (mass ratio: 60/40), and the average particle size as particles 2.2 μm styrene-benzoguanamine-based spherical organic particles (manufactured by Nippon Shokubai Kogyo Co., Ltd.) and colloidal silica having an average particle size of 0.02 μm (manufactured by Catalyst Kasei Co., Ltd.) are mixed so that the solids mass ratio is 50/1/3. Then, a coating solution A was prepared.

(Preparation of coating solution B for easy slipperiness improving layer)
In a mixed solvent of ion-exchanged water and isopropyl alcohol (mass ratio: 60/40), a water-dispersible polyester copolymer (manufactured by Toyobo Co., Ltd. MD-16), sodium dodecyl diphenyloxide disulfonate (manufactured by Matsumoto Yushi Co., Ltd., an anionic antistatic agent) as a metal salt of sulfonic acid, polyethylene emulsion wax (manufactured by Toho Chemical Co., Ltd.) as a polymer wax agent, and particles Styrene-benzoguanamine-based spherical organic particles (manufactured by Nippon Shokubai Kogyo Co., Ltd.) having an average particle size of 2.2 μm and colloidal silica (manufactured by Nissan Chemical Co., Ltd.) having an average particle size of 0.04 μm in a solid content mass ratio of 50 / 2.5 / The mixture was mixed to 2.5 / 0.5 / 5 to prepare coating solution B.

(Preparation of polyester film for laminate molding)
100 mol% terephthalic acid unit as the aromatic dicarboxylic acid component, 92 mol% ethylene glycol unit and 8 mol% neopentylglycol unit as the diol component, 400 ppm amorphous silica with an average particle size of 1.5 μm and antioxidant 1 part by weight of hindered phenolic antioxidant (Ciba Geigy, Irganox 1010) as an additive with respect to 100 parts by weight of polyester, and benzotriazole UV absorber (Ciba Specialty Chemicals, Inc., Tinuvin 326) A copolyester composition having an intrinsic viscosity of 0.69 dl / g and containing 0.5 parts by mass with respect to 100 parts by mass of polyester was prepared. This copolyester composition was pre-crystallized and then dried, melt-extruded at 290 ° C. using an extruder having a T die, and rapidly cooled and solidified on a drum having a surface temperature of 40 ° C. to obtain an amorphous sheet.

  Next, this cast film was stretched 3.5 times at 80 ° C. in the longitudinal direction between a heating roll and a cooling roll to obtain a uniaxially oriented polyester film.

Next, the coating liquid A was applied to one side of the polyester film for uniaxial orientation molding, and the coating liquid B was applied to the other side by a reverse coating method so that the coating amount was 6 g / m ² . In addition, each coating liquid applied a shear rate of 1000 (1 / second) or more between the roll gaps, applied to the substrate film within 2 seconds, and in an environment of 65 ° C., 60% RH, and wind speed of 15 m / second, Dry for 2 seconds. Further, it was dried for 3 seconds in an environment of 130 ° C. and a wind speed of 20 m / second to remove moisture.

  Next, the film edge is continuously held by a clip and guided to a tenter, preheated at 100 ° C. for 15 seconds, the first half of transverse stretching is stretched 3.6 times at 115 ° C. and the latter half is 95 ° C., 7% Then, heat treatment was performed at 205 ° C. while relaxing in the transverse direction to obtain a biaxially stretched polyester film having a thickness of 188 μm. The obtained film had a melting point of 232 ° C. and an intrinsic viscosity of 0.61 dl / g. The characteristics and evaluation results of the obtained film are shown in Tables 1 and 2.

Example 2
In Example 1, a biaxially stretched polyester film was obtained in the same manner as in Example 1 except that the thickness of the film was 100 μm. The characteristics and evaluation results of the obtained film are shown in Tables 1 and 2.

Example 3
In the method of Example 1, the polyester resin is composed of 100 mol% terephthalic acid unit as the aromatic dicarboxylic acid component, 90 mol% ethylene glycol unit and 10 mol% 1,4-cyclohexanedimethanol unit as the diol component, An amorphous sheet was obtained in the same manner as in Example 1 except for changing to a copolymer polyester having an intrinsic viscosity of 0.71 dl / g.

  The obtained sheet was stretched 3.0 times at 75 ° C. in the longitudinal direction between the heating roll and the cooling roll, and then the uniaxially stretched sheet was led to a tenter. Next, preheating at 105 ° C. for 15 seconds, the first half of the transverse stretching is 125 ° C., the latter half is stretched 3.6 times at 98 ° C., and heat treatment is performed at 205 ° C. while relaxing 7% in the transverse direction. A biaxially stretched polyester film having a thickness of 188 μm was obtained. The obtained film had a melting point of 228 ° C. and an intrinsic viscosity of 0.62 dl / g. The characteristics and evaluation results of the obtained film are shown in Tables 1 and 2.

Comparative Example 1
In Example 1, the polyester resin was changed to polyethylene terephthalate, longitudinally stretched 3.7 times at 90 ° C, and then stretched 4.0 times at 120 ° C, and then relaxed by 10% in the transverse direction. A biaxially stretched polyester film was obtained in the same manner as in Example 1 except that heat treatment was performed at ° C. The obtained film had a melting point of 265 ° C. and an intrinsic viscosity of 0.61 dl / g. The characteristics and evaluation results of the obtained film are shown in Tables 1 and 2.

Comparative Example 2
In Example 1, the film was longitudinally stretched 3.5 times at 125 ° C., then transversely stretched 3.5 times at 130 ° C., and then heat treated at 230 ° C. An axially stretched polyester film was obtained. The characteristics and evaluation results of the obtained film are shown in Tables 1 and 2.

Comparative Example 3
In Example 1, the composition ratio of ethylene glycol and neopentyl glycol in the polyester composition is 85 mol% and 15 mol%, respectively, the blending of the hindered phenol antioxidant is stopped, and the melt extrusion temperature is 280 ° C. Except for this, a biaxially stretched polyester film was obtained in the same manner as in Example 1. The obtained film had a melting point of 205 ° C. and an intrinsic viscosity of 0.57 dl / g. The characteristics and evaluation results of the obtained film are shown in Tables 1 and 2.

Comparative Example 4
In the method of Example 3, except that the composition ratio of the ethylene glycol unit and the 1,4-cyclohexanedimethanol unit in the polyester composition is 75 mol% and 25 mol%, respectively, and the blending of the hindered phenol antioxidant is stopped. In the same manner as in Example 3, a biaxially stretched polyester film was obtained. The obtained film had an intrinsic viscosity of 0.55 dl / g. The characteristics and evaluation results of the obtained film are shown in Tables 1 and 2.

Comparative Example 5
Intrinsic viscosity containing 90 mol% of terephthalic acid unit and 10 mol% of adipic acid as dicarboxylic acid components and 100 mol% of ethylene glycol units as diol components and 800 ppm of amorphous silica having an average particle size of 1.4 μm A copolyester of 0.71 dl / g was used. However, the addition of a hindered phenolic antioxidant and an ultraviolet absorber (Tinuvin 326) was stopped. Furthermore, a biaxially stretched polyester film was obtained in the same manner as in Comparative Example 3 except that the lamination of the coating layer by the inline coating method was stopped. The obtained film had a melting point of 230 ° C. and an intrinsic viscosity of 0.55 dl / g. The characteristics and evaluation results of the obtained film are shown in Tables 1 and 2.

Comparative Example 6
The terephthalic acid unit is 100 mol% as the aromatic dicarboxylic acid component, the ethylene glycol unit is 95 mol%, the 1,4-cyclohexanedimethanol unit is 3 mol%, and the diethylene glycol unit is 2 mol% as the diol component. A copolyester composition having an intrinsic viscosity of 0.67 dl / g and containing 2000 ppm of 6 μm aluminum silicate was prepared. This copolyester composition was pre-crystallized and then dried, melt-extruded at 280 ° C. using an extruder having a T die, and rapidly cooled and solidified on a drum having a surface temperature of 40 ° C. to obtain an amorphous sheet. The characteristics and evaluation results of the obtained film are shown in Tables 1 and 2.

  The obtained sheet was stretched 3.4 times at 96 ° C. in the longitudinal direction between the heating roll and the cooling roll, and then the uniaxially stretched sheet was led to a tenter. Next, the film is preheated at 100 ° C. for 15 seconds, stretched 3.3 times in the transverse direction at 115 ° C., heat-treated at 180 ° C. while relaxing 5% in the transverse direction, and has a thickness of 188 μm. Got. The intrinsic viscosity of the obtained film was 0.55 dl / g. The characteristics and evaluation results of the obtained film are shown in Tables 1 and 2.

  The film obtained in Examples 1 to 3 was a film having good moldability with little printing displacement at the time of molding and less trouble with perforation at the time of molding the mold.

Example 4
The design was printed on the surface of the biaxially stretched polyester film obtained in Examples 1 to 3 by offset printing using UV ink. Next, the printed body was press-molded at a mold temperature of 100 ° C., and a name plate for a switch having an indentation depth of 2.0 mm was produced. There was no occurrence of perforation problems during molding, the operability of the molding work was good, and the appearance of the nameplate obtained was good. Moreover, the printing property of printing, the durability of the printing layer, and the printing operability were good, and the light resistance of the obtained nameplate was good.

Comparative Example 7
The polyester film for biaxial stretching molding obtained in Comparative Examples 1 to 5 was press-molded in the same manner as in Example 4. The films of Comparative Examples 1, 2, 5 and 6 were inferior in moldability, and the films of Comparative Examples 1, 3, 4, 5 and 6 were inferior in operability of the molding operation. In addition, the films obtained in Comparative Examples 5 and 6 were inferior in printability of printing, durability of the printed layer, and print operability, and inferior in light resistance of the nameplates obtained.

  The molding polyester film of the present invention is excellent in moldability at the time of heating, rigidity at the time of use as a molded body, and shape stability (thickness unevenness, heat shrinkage characteristics). In addition, it has excellent moldability such as in-mold moldability, emboss moldability, and vacuum moldability, particularly moldability in mold molding and insert molding, and has good printability, printing durability, and printing operation. It can be suitably used as a molded member in fields such as home appliances, automobiles, and building materials.

Claims (18)

  A molding polyester film comprising a copolyester composed of an aromatic dicarboxylic acid component and a glycol component containing ethylene glycol and a branched aliphatic glycol and / or alicyclic glycol, wherein the film is in the longitudinal direction And the stress at 100% elongation in the width direction is 180 to 1000 MPa at 25 ° C. and 1 to 100 MPa at 100 ° C., and the intrinsic viscosity is 0.58 dl / g or more. A polyester film for molding, comprising a printability improving layer.   The polyester film for molding according to claim 1, wherein the branched aliphatic glycol is neopentyl glycol.   The polyester film for molding according to claim 1 or 2, wherein the alicyclic glycol is 1,4-cyclohexanedimethanol.   The polyester film for molding according to any one of claims 1 to 3, wherein the aromatic dicarboxylic acid component is terephthalic acid, naphthalenedicarboxylic acid, or an ester-forming derivative thereof.   The said film contains 0.05-5 mass% of antioxidant with respect to copolyester, The polyester film for shaping | molding in any one of Claims 1-4 characterized by the above-mentioned.   The molding film according to claim 1, wherein the film has a melting point of 220 to 245 ° C.   The adhesive modification resin is made of at least one resin selected from the group consisting of polyester resin, polyurethane resin, acrylic resin, amino resin, epoxy resin, and oxazoline resin, and a printability improving layer is provided. The polyester film for molding according to any one of claims 1 to 6, which is formed by an in-line coating method.   The polyester film for molding according to any one of claims 1 to 7, wherein a water resistance value of the printability improving layer is 90% or more.   9. The molding polyester film according to claim 8, wherein the adhesive property modifying resin is made of a resin obtained by graft-modifying a hydrophobic copolymerized polyester resin with an unsaturated bond-containing monomer.   The polyester film for molding according to any one of claims 1 to 9, wherein a slipperiness improving layer containing particles and / or wax is laminated on the opposite surface of the printability improving layer.   The slipperiness improving layer comprises (a) a copolymer polyester resin, (b) a compound having a sulfonate group, (c) particles having an average particle diameter of 1.0 to 5.0 μm, and (d) a polymer wax. The molding polyester film according to claim 1, comprising a composition comprising   The polyester film for molding according to any one of claims 1 to 11, wherein both the static friction coefficient and the dynamic friction coefficient when the printability improving layer and the slipperiness improving layer are overlapped are 0.5 or less.   The polyester film for molding according to any one of claims 1 to 12, wherein the film has a thickness of 60 to 500 µm.   The polyester film for molding according to any one of claims 1 to 13, wherein the film has a thickness unevenness of 5.5% or less.   The polyester film for molding according to any one of claims 1 to 14, wherein the film has a heat shrinkage in the longitudinal direction and the width direction at 150 ° C of 6.0% or less.   The molding polyester film according to claim 1, wherein the film has a ratio (H / d) of haze H (%) to thickness d (μm) of 0.030 or less.   The polyester film for molding according to any one of claims 1 to 16, wherein the film has a light transmittance at a wavelength of 380 nm of 50% or less.   A molded member obtained by molding the molding polyester film according to claim 1 by a mold molding method or an insert molding method.