JP2005066939A - Molding polyester film and dummy container obtained therefrom - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a molding polyester film excellent in moldability at the time of heating molding, excellent in elasticity and form stability (heat shrinkage characteristics and thickness irregularity) at the time of use as a molded object under a normal temperature atmosphere, excellent in paper feed stability, ink adhesion and damping water aptitude in a multicolor printing high speed UV offset press and susceptible to high speed/high grade printing. <P>SOLUTION: The molding polyester film is obtained by using a polyester film as a base material and laminating an easily printable coating layer on one side of the base material while laminating an easy slip coating layer on the other surface thereof. The base material comprises a polyester film containing a copolyester synthesized from an aromatic dicarboxylic acid component and a glycol component containing EG and a branched aliphatic glycol and/or an alicyclic glycol and is constituted so that the stress at the time of 100% elongation in the longitudinal and lateral directions thereof is 180-1,000 MPa at 25°C and 1-100 MPa at 100°C. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention is excellent in in-mold moldability, emboss moldability, printability, transparency and the like, and excellent in heat resistance, and is obtained from the polyester film for molding suitable as a member for home appliances, automobile nameplates or building materials. It relates to a dummy container.

  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 is poor in stability and poor in strength and elasticity not only at the time of molding but also when actually used as a molded body. If the copolymer composition ratio of the above components is decreased in order to increase the stability, the moldability is lowered, and it is difficult to achieve both moldability, strength and elasticity.

For example, a polyester film 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 copolymer polyester films described in these conventional techniques have a thickness of 50 μm or less, film formation is relatively easy.
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, and elasticity and morphology. Stability may be insufficient. Therefore, there has been a demand for a polyester film that is excellent in elasticity and shape stability (heat shrinkage characteristics, thickness unevenness) when using a molded body in a room temperature atmosphere while maintaining moldability.

On the other hand, in a vending machine for beverages in bottles and cans, dummy containers are displayed instead of actual containers as sample products. Conventionally, a plastic container that faithfully copies the actual product has been used. As these dummy container films, a heat-shrinkable polyester film intended for surface decoration of a container having a complicated shape is disclosed (for example, see Patent Document 3).
JP-A-4-199397

  However, in recent years, in response to demands for space saving and the like of vending machines, the dummy container is also being switched from a fully imitated type to a partially imitated type. That is, in the case of the dummy container, it is only necessary to understand the contents of the product when viewed from substantially the front. The partially-shaped dummy container is produced by, for example, molding a printed polyester film into a substantially half shape by press molding or the like. Therefore, the display subspace can be reduced by the correspondence, and the economy is greatly improved. However, in recent years, beverage containers have become more sophisticated, the container shape has become more complex, and the printing on the surface layer has become more demanding for complicated and fine prints. With conventional polyester films, moldability and printability have increased. In this respect, it has become impossible to meet market demands sufficiently.

  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 have elasticity and shape stability (heat shrinkage characteristics, thickness unevenness when used in a room temperature atmosphere as a molded body. And a dummy container obtained therefrom. In particular, in addition to easy moldability, to provide a polyester film for molding that is excellent in sheet feeding stability, ink adhesion, dampening water suitability, etc. in a high-speed UV offset printing press for multicolor printing and capable of high-quality printing. is there.

  That is, the present invention uses a polyester film as a base material, and an easy-printing coating layer containing an adhesion-modifying resin is laminated on one side of the base material, and an easy-sliding coating layer containing particles and / or wax is laminated on the other side. A polyester film for molding, wherein the base material is a copolymer synthesized from an aromatic dicarboxylic acid component and a glycol component containing ethylene glycol and a branched aliphatic glycol and / or alicyclic glycol It is a polyester film for molding, comprising a polyester film containing polyester and having a stress at 100% elongation in the longitudinal and width directions of 180 to 1000 MPa at 25 ° C. and 1 to 100 MPa at 100 ° C. Moreover, this invention is the dummy container obtained from the said polyester film for a shaping | molding.

  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 moldability during heating and when used as a molded body Is excellent in elasticity and shape stability (thickness unevenness, heat shrinkage characteristics). Furthermore, since an easy-printing coating layer is laminated on one side of the base film and an easy-slipping coating layer is laminated on the other side, in addition to the above-mentioned easy moldability, feeding in a high-speed UV offset printing machine for multicolor printing It is excellent in stability, ink adhesion, dampening water suitability, etc., and can perform high-quality printing at high speed.

(Function)
The molding polyester film of 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 molding polyester film of the present invention using such a copolyester as a film raw material has excellent moldability in a high temperature atmosphere during molding, and elasticity and shape stability in a normal temperature atmosphere used as a molded body ( It is a polyester film that has a feature of excellent heat shrinkage characteristics and uneven thickness) and is 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 the longitudinal direction and the width direction of the film under an atmosphere of 25 ° C. is 180 to 1000 MPa from the viewpoint of achieving both elasticity and shape stability (thickness variation, thermal shrinkage at 150 ° C.) and moldability. It is important that

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

  On the other hand, in the case of a highly elastic film having a stress at 100% elongation in the 25 ° C. atmosphere exceeding 1000 MPa, the moldability during 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, when the stress at 100% elongation in a 100 ° C. atmosphere decreases, the stress at 100% elongation at 25 ° C. also decreases, and the elasticity 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.

  Furthermore, from the point of balance of moldability in the vertical direction and the horizontal direction, the stress ratio at 100% elongation in the longitudinal direction and the width direction at 100 ° C. (the higher numerical value / the lower numerical value) is 1.05-1. .60 is preferred. The upper limit is particularly preferably 1.40. When the upper limit value exceeds 1.60, dimensional stability at the time of molding, printing deviation, and the like are likely to deteriorate.

  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 more than 50 μm and 500 μm or less from the viewpoints of moldability, covering property when providing a printed layer to enhance the design of the film, film surface protection, and design. It is 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 3.0% or less reduces printing deviation after providing a printing layer on the molding polyester film in order to enhance the design. To preferred.

  In addition, the molding film preferably has a haze H (%) ratio (H / d) of 0.030 or less to a thickness d (μm) 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 from the viewpoint of transparency and print sharpness, but if the necessary minimum unevenness is not formed on the film surface, handling properties such as slipperiness and rollability deteriorate, Since the film surface may be scratched or productivity may deteriorate, the lower limit value of H / d is preferably set to 0.001, particularly preferably 0.005. 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 polyester film of the present invention is formed by laminating an easy-printing coating layer containing an adhesive modification resin on one side of the above-mentioned base film and an easy-sliding coating layer containing particles and / or wax on the other side. In addition, it is excellent in sheet feeding stability, ink adhesion, suitability for fountain solution, etc. in a high-speed UV offset printing machine for multicolor printing, and enables high-quality printing.

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

  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 with 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, examples of other glycol components that can be used together with ethylene glycol and branched aliphatic glycol and / or alicyclic glycol include 1,3-propanediol, 1,4-butanediol, pentanediol, and 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.

  The copolyester preferably has an intrinsic viscosity of 0.50 dl / g or more, more preferably 0.55 dl / g or more, and particularly preferably 0.00 from the viewpoint of moldability, adhesiveness, and film formation stability. 60 dl / g or more. If the intrinsic viscosity is less than 0.50 dl / g, the moldability tends to decrease.

  In the polyester film of the present invention, the copolymer polyester may be used as a film raw material as it is, or a copolymer polyester having a large amount of copolymer components may be blended with a homopolyester to adjust the amount of copolymer components.

  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 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 film in the present invention is preferably 230 to 270 ° C. from the viewpoint of heat resistance and moldability. The lower limit of the melting point is more preferably 235 ° C, particularly preferably 240 ° C. If the melting point is less than 230 ° C, the heat resistance tends to deteriorate. Therefore, it may become a problem when exposed to high temperatures during molding or use of the molded body. Here, the melting point of the polyester film is an endothermic peak temperature at the time of melting detected at the time of primary temperature rise in so-called differential scanning calorimetry (DSC).

  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.

  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, the frequency of coarse protrusions and deterioration of film forming property tends to increase.

  The polyester film of the present invention is preferably an unstretched film for applications that require moldability with large deformation. 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 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.

  Although it does not specifically limit as a manufacturing method of the polyester film of this invention, For example, after drying polyester as needed, it supplies to a well-known melt extruder, it extrudes in a sheet form from a slit-shaped die, an electrostatic application etc. The method of sticking to a casting drum by this method, cooling and solidifying to obtain an unstretched sheet, and then biaxially stretching the unstretched sheet is exemplified.

  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 polyester film of the present invention, (1) a copolymer polyester comprising terephthalic acid and ethylene glycol or neopentyl glycol, or (2) a copolymer polyester comprising terephthalic acid, ethylene glycol or 1,4-cyclohexanedimethanol is used. In this case, in order for the stress at 100% elongation in the longitudinal direction and the width direction to be 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 width The stretching ratio in the direction is preferably 3.0 to 4.5 times.

  The stretching conditions for producing the 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., and the preheating temperature is preferably +5 to 25 ° C. in the first half of the transverse stretching, and the first half is preferably −15 to −40 ° C. in the second half of the transverse stretching. 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 22.5-5.0 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.

  Further, the film is subjected to heat treatment 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 lateral direction at 150 ° C., it is preferable to increase the heat treatment temperature, lengthen the heat treatment time, and perform relaxation treatment. It is difficult to lengthen the line and increase the heat treatment time due to equipment limitations. Further, when the film feeding speed is slowed, productivity is lowered.

  In order to set the thermal shrinkage rate in the longitudinal direction and the width direction at 150 ° C. to 3.0% 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.

  The polyester film for molding of the present invention is formed by laminating an easy-printing coating layer containing an adhesive property-modifying resin on one side of the base material and an easy-sliding coating layer containing particles and / or wax on the other side. There is a need. This configuration is excellent in sheet feeding stability, ink adhesion, dampening water suitability, etc. in a high-speed UV offset printing press for multicolor printing, and enables high-quality printing. For example, high-quality printing and printing for dummy containers, etc. It is possible to meet market demands in fields where economic efficiency is required.

  In the present invention, the easy-printing coating layer is not particularly limited as long as it has a function of improving the printability of the polyester film for molding the base material. (A) a polyester-based graft copolymer obtained by grafting an acid anhydride having at least one double bond to a hydrophobic copolyester resin; (b) particles having an average particle size of 1.0 to 5.0 μm In a preferred embodiment, the composition comprises

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

  A polyester-based graft copolymer obtained by grafting an acid anhydride having at least one double bond to the hydrophobic copolymerized polyester resin 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, the adhesion with the printing layer applied to the primer layer (coating layer A in the present invention) tends to be insufficient.

  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, and the transparency of the coating is lowered. When the average particle diameter is less than 10 nm, the water-resistant adhesion tends to be lowered.

  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.

  In view of increasing the acid value of the present invention, it is preferable that a radical polymerizable monomer containing a carboxyl group or having a group capable of generating a carboxyl group is contained.

  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 in relation to adhesion 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-resistant adhesion 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 tends to decrease.

  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. If it exceeds 1, the viscosity will increase too late in the grafting reaction, which tends to hinder the uniform progress of the reaction. 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-sodiumsulfoisophthalic acid from the viewpoint that the water-resistant adhesion decreases.

  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. If the weight average molecular weight is less than 5,000, the adhesive strength tends to decrease, and conversely if it exceeds 50,000, problems such as gelation during polymerization tend to 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 carried out with a single solvent, only one 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 from only 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 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 with a boiling point of 100 ° C. or lower is used, there are few residual basic compounds in the coating film after drying, adhesion of metals and inorganic deposited films, and water resistance adhesion when laminated with other materials Excellent heat and water resistance.

  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. For the first time, adhesion and water-resistant adhesion can be exhibited. 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.

  Specifically, the insoluble fraction of the coating film obtained by drying at 80 ° C. or less 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 fraction of the coating film is less than 50% by mass, not only the adhesion and water-resistant adhesion are not sufficient, but also the frequency of causing blocking increases.

  The copolyester resin forming the slippery coating layer of the present invention is a copolyester polycondensate comprising at least one dicarboxylic acid component, at least one diol component, and their ester-forming components as constituent units. The same kind of polyester resin as the coating layer A (hereinafter sometimes referred to as a printing layer) 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.

  It is preferable that the resin component of these easy-printing coating layers and easy-sliding coating layers is 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 used in the present invention 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, methallyl sulfonic acid). A polymer antistatic agent comprising one or more polymers of sodium, sodium styrenesulfonate, ammonium vinylsulfonate, potassium methacrylsulfonate, lithium styrenesulfonate, etc., and R-SO ₃ X (where R Is an alkyl group, an aryl group, or an aromatic group having an alkyl group, and X is a low molecular charge of a metal ion (for example, Li, Na, K, etc.), ammonium ion, amine ion, or phosphate ester ion) Antibacterial agent and its dimer are listed, but it has a sulfonate group with excellent heat resistance and antistatic properties. It has a function that expresses, but is not limited to the compound.

  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 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-resistant adhesion 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, 5-50 mass% is preferable, Most preferably, it is 10-30 mass%. A mixture of the low molecular compound and the high molecular compound may be used. Further, the surface specific resistance value of the coating layer containing the compound having a sulfonate group should be not more than 10 ¹³ Ω / □ under the conditions of 23 ° C. and 50% RH. The slipperiness becomes insufficient under a low load, and the transportability such as double feeding in a high-speed printer tends to deteriorate. On the other hand, when the content of the compound having a sulfonate group is too large, the printed surface is likely to be contaminated due to set-off or particle dropout.

  Commercially available inorganic particles and / or organic particles can be used as the particles having an average particle diameter of 1 to 5 μm that can be used in the present invention. 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. 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.

  Moreover, content with respect to the resin component of the said particle | grain in a coating 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 coating 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 5 μm, or when the particle content exceeds 10% by mass, the haze of the film increases, the transparency is deteriorated, or the particles are dropped, resulting in a print surface stain, a problem of print quality, The frequency of machine stand contamination increases.

  The polymer wax component used in the present invention is not particularly limited as long as it does not impair the transparency, and conventionally known ones 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 may adversely affect the ink adhesion.

  When the molecular weight exceeds 10,000, the effect of improving slipperiness may be 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 it becomes difficult to increase the printing speed. When the content of the wax component in the coating layer with respect to the resin component exceeds 10% by mass, the wax component is easily removed, which easily causes contamination of the printed surface, and further deterioration of transparency and haze.

  In the present invention, the slipperiness of the molding polyester film in which the coating layers are formed on both sides may be, for example, as long as the sheet feeding stability in the high-speed UV offset printing machine, which is the feature of the present invention, can be given. The static friction coefficient and the dynamic friction coefficient when the easy-printing coating layer and the slippery coating layer are overlaid are preferably 0.5 or less.

  In a state where the dynamic friction coefficient exceeds 0.5, the slipperiness is insufficient, and a conveyance failure occurs when feeding with 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 coating layers, the coefficient of friction rises gently with friction running, 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-described coating layer on both sides of the polyester base film is not limited and is arbitrary, but a method of carrying 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. In particular, when producing a polyester base film, a so-called in-line coating method is applied 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 polyester film is completed. This is a preferable method that can exhibit the effect of the above.

  The above-mentioned copolymerized 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, wind speed 10-20 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 restrictions on the heat setting conditions after stretching after coating and drying in the case of the in-line coating method described above, but the self-crosslinking property of the polyester-based graft copolymer, which is a constituent component of the easy-printing coating layer, in particular. 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, and 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.

  In the present invention, the slipperiness between the easily printable coating layer and the slippery coating layer on the opposite side is very good as compared with a conventionally known method. This remarkable improvement in slipperiness when films are stacked in sheet form is as follows: (1) Air retention effect between films due to surface irregularities caused by particles having an average particle diameter of 1 to 10 μm contained in the coating layers on both sides (2) The effect of preventing electrostatic adhesion due to the sulfonic acid metal salt contained in the slippery coating layer, and (3) the reduction in the static friction coefficient due to the polymer wax component contained in the slippery coating layer. If these three effects are not all available, the cut film will not be smooth enough when it starts to move from a stationary state, the transportability from a stack of sheets in a sheet-like state, and the biting stability during feeding will be inferior. The printing speed cannot be increased.

  A laminated film having a normal coating layer has inert particles for forming irregularities on the film surface for the purpose of improving handling properties (e.g., slipperiness, winding property, blocking resistance) and scratch resistance. Contained. However, the laminated polyester film of the present invention preferably contains particles in the coating layer to improve transparency, and the content of particles in the base film is preferably reduced. It is particularly preferable not to contain it. “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 laminated polyester film 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. As a result, the brightness when illuminated 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 obtained. It is done.

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

  If the adhesion force (remaining ratio of the number of squares) is less than 90%, ink dropout after printing occurs, 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 polyester film.

  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 polyester film.

  The molding polyester film of the present invention is used by applying heat, pressure, or the like to be deformed. Examples of the molding means include pressure molding, press molding, laminate molding, vacuum molding, vacuum / pressure molding, in-mold molding, drawing molding, and bending molding. The molded body molded in this way is used for molding members such as home appliance nameplates, automobile nameplates, dummy containers, building materials, decorative boards, decorative steel plates, transfer sheets, etc., but it is used as a dummy container member. Since the effects of the present invention can be suitably expressed, this is a preferred embodiment.

  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 kg. 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 g. 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, under a constant tension of 5 g (tension in the length direction), the interval B between the two marks is read with a gold finger in units of 0.25 mm. 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, after heating at 130 ° C. for 5 seconds, press molding was performed at a mold temperature of 80 ° C. and a pressure holding time of 5 seconds. ABS resin was poured into the molding material at 210 ° C. (injection molding), and a key top having a height of 3.0 mm, the surface of which was covered with a film, was created. The printing misalignment at this time was measured, and the molding state was visually observed and ranked according to the following criteria. In addition, ◎ and ○ were accepted and x was rejected.

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

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

(10) Ink Adhesion Strength According to the cross-cut evaluation method described in 8.5.1 of JIS-K5400, the ink adhesion strength of the printed surface of the film (easily printable coating layer in the present invention) was evaluated. Specifically, after printing the following ink on the printing surface of the film, using a crosscut guide, 100 pieces of 1 mm squares were created on the printing surface with a cutter blade, and then an adhesive tape (product name cellophane tape, manufactured by Nichiban Co., Ltd.). ) Was affixed to the printed surface and completely adhered so that no air remained. Next, after the adhesive tape was peeled off vertically, the remaining number of squares on the printed surface was evaluated as the adhesion (remaining number / 100).

  The adhesive strength with the UV curable ink was UV curable ink (manufactured by Toka Dye Co., Ltd., Best Cure 161), and the film was coated with a RI tester on the coating layer surface (easily printable coating layer of the present invention). Were evaluated according to the above method. Also, using another UV curable ink (Seiko Advance, UVA), the surface of the coating layer (easily printable coating layer of the present invention) was irradiated with 500 mJ of UV after # 300 screen printing, and the above method was applied. Therefore, it evaluated similarly.

  Adhesive strength with solvent-type ink is solvent-type ink (TSP-400G, manufactured by Toyo Ink Co., Ltd.). It is left to dry for 24 hours after printing on the coating layer surface (easily printable coating layer of the present invention) with an RI tester. Evaluation was made according to the above method. Also, using other solvent-based ink (Tetron, manufactured by Jujo Ink Co., Ltd.), the coating layer surface of the film (the easy-printing coating layer of the present invention) was left to dry for 24 hours after screen printing of # 250, and the same procedure was followed according to the above method. Evaluated.

(11) Suitability for fountain solution When using a solvent-type offset printing ink (manufactured by Toyo Ink Co., Ltd., TSP-400G) and printing on the coating layer surface (easily printable coating layer of the present invention) with an RI tester, ink color development After the previous film printing surface was pressure-bonded with a Molton roller moistened with 0.2 ml, 0.4 ml, and 0.6 ml of ion-exchanged water using a dropper, the ink was developed, and there was no ink transfer failure. Were evaluated comprehensively and judged by ○ and х.

(12) Feeding stability Using a sheet-fed offset printing machine (Heidelberg, Speedmaster, 8-color printing machine), stacking sheets of Kikuzen size (636 x 939 mm) size sheets at low printing speed The sheet feeding stability was evaluated when feeding and printing at (4,000 sheets / hour) and at high speed (8,000 sheets / hour). ◯ when the paper could be fed stably, and х when troubles such as double feeding and clogging occurred during feeding.

(13) Print quality The print appearance of the print sample used in the feed stability evaluation was visually determined. At this time, the appearance was visually judged through the film from the back side, not from the printed surface. A sample having a clear feeling and printability satisfying the following criteria was evaluated as “Good”.
(Clear feeling)
The printed design looks clear without being blocked by the base film or coating layer (printability)
Color unevenness and missing due to poor transfer of printing ink

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. Next, 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 liquid A for easy-printing coating 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 (manufactured by Catalyst Kasei Co., Ltd.) having an average particle size of 0.02 μm are mixed so that the solids mass ratio is 50/3. Then, a coating solution A was prepared.

(Preparation of coating liquid B for slippery coating 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., Bayroner) so that the total solid content concentration is 5% by mass. MD-16), sodium dodecyl diphenyl oxide disulfonate (manufactured by Matsumoto Yushi Co., Ltd., an anionic antistatic agent) as a sulfonic acid metal salt, 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 Industries, 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 laminated polyester film)
Containing 100 mol% of terephthalic acid units as aromatic dicarboxylic acid components, 85 mol% of ethylene glycol units and 15 mol% of neopentylglycol units as diol components, and containing 400 ppm of amorphous silica having an average particle size of 1.5 μm, A copolyester having an intrinsic viscosity of 0.69 dl / g is 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 be amorphous. A sheet was obtained.

  Next, this cast film was stretched 3.4 times at 80 ° C. in the longitudinal direction between a heating roll and a cooling roll to obtain a uniaxially oriented polyester film.

  Subsequently, said coating liquid A was apply | coated to the one surface of the uniaxially-oriented polyester film, and the coating liquid B was apply | coated to the other surface by the reverse coat method. 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 with a clip and guided to a tenter, preheated at 105 ° C. for 15 seconds, the first half of the 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.

Comparative Example 1
In Example 1, the film was longitudinally stretched 3.0 times at 98 ° C., and then pre-heated at 140 ° C. for 15 seconds, and then the entire stretched portion was stretched 4.0 times at 140 ° C. Thereafter, a biaxially stretched polyester film was obtained in the same manner as in Example 1 except that heat treatment was performed at 200 ° C. while relaxing 10% in the lateral direction.

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.

Comparative Example 3
In the method of Example 1, a biaxially stretched polyester film was obtained in the same manner as in Example 1 except that the application of the coating solution for forming the easily printable coating layer and the slippery coating layer on the uniaxially oriented polyester film was stopped. It was.

Example 2
Copolyester having an intrinsic viscosity of 0.71 dl / g, comprising 100 mol% of terephthalic acid units as the aromatic dicarboxylic acid component and 90 mol% of ethylene glycol units and 10 mol% of 1,4-cyclohexanedimethanol units as the diol component. After preliminary crystallization, this was 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.

  After the obtained sheet was stretched 3.0 times at 75 ° C. in the longitudinal direction between the heating roll and the cooling roll, the coating liquid A and The coating liquid B was applied, and the uniaxially stretched sheet was guided to a tenter. Next, preheating at 107 ° 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 250 μm was obtained.

Example 3
In Example 1, the amorphous dicarboxylic acid component consists of 100 mol% of terephthalic acid units, the diol component consists of 80 mol% of ethylene glycol units and 20 mol% of neopentylglycol units, and has an average particle size of 1.4 μm. Except that the copolyester having an intrinsic viscosity of 0.69 dl / g and the polyethylene terephthalate having an intrinsic viscosity of 0.70 dl / g were dried and pre-crystallized and then mixed at 1: 1 (mass ratio). In the same manner as in Example 1, a biaxially stretched polyester film was obtained.

Comparative Example 4
Intrinsic viscosity of 90 mol% terephthalic acid unit and 10 mol% of adipic acid as dicarboxylic acid component, 100 mol% of ethylene glycol unit as diol component, and 800 ppm of amorphous silica having an average particle size of 1.4 μm. A biaxially stretched polyester film was obtained in the same manner as in Example 1 except that a copolyester of .71 dl / g was used.

Comparative Example 5
The aromatic dicarboxylic acid component is composed of 100 mol% of terephthalic acid units, the diol component is composed of 95 mol% of ethylene glycol units, 3 mol% of 1,4-cyclohexanedimethanol units, and 2 mol% of diethylene glycol units. A copolyester having an intrinsic viscosity of 0.67 dl / g containing 2000 ppm of 6 μm aluminum silicate was pre-crystallized, then fully dried, and melt-extruded at 280 ° C. using an extruder having a T-die, and a surface temperature of 40 An amorphous sheet was obtained by rapid solidification on a ℃ drum.

  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 evaluation results of the films obtained in each Example and Comparative Example are shown in Tables 1 and 2.

Example 4
The film obtained in Examples 1 to 3 is a sheet of offset size printing machine (manufactured by Heidelberg, Speedmaster, 8-color printing machine) using UV curable ink and having a size of Kikuzen (636 × 939 mm) size. The leaf films were stacked, fed at a printing speed of 8,000 sheets / hour, and printed on the easily printable coating layer surface. The printing operability and the printing characteristics of the printed product were good. The obtained polyester film for molding was press-molded at a mold temperature of 100 ° C. to produce a constricted dummy beverage bottle (a shape obtained by half-cutting an actual bottle). Molding operability and the appearance of the obtained dummy beverage bottle were good.

  The molding polyester film of the present invention is excellent in moldability at the time of heating and elasticity and shape stability (thickness unevenness, heat shrinkage characteristics) when used in a room temperature atmosphere as a molded body. It is suitable as a film for various types of molding such as embossing and vacuum forming. Furthermore, easy molding, which is a feature of the base material, is made by stacking the easy-printing coating layer A on one side of the base material and the easy-sliding coating layer B on the other side. In addition to the properties and light resistance, it is excellent in paper feeding stability, ink adhesion, dampening water suitability, etc. in a high-speed UV offset printing machine for multicolor printing, and can perform high-quality printing at high speed, so it is a member of a dummy container It is suitable as. Furthermore, it is also suitable as a member for nameplates of home appliances and automobiles, or a member for building materials.

Claims (11)

  Polyester for molding comprising a polyester film as a base material, and an easy-printing coating layer containing an adhesive property-modifying resin on one side of the base material and an easy-sliding coating layer containing particles and / or waxes on the other side. The base material is a polyester film comprising a copolymer polyester synthesized from an aromatic dicarboxylic acid component and ethylene glycol and a glycol component containing a branched aliphatic glycol and / or an alicyclic glycol. And a stress at 100% elongation in the longitudinal and width directions is 180 to 1000 MPa at 25 ° C. and 1 to 100 MPa at 100 ° C.   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 film has a 100% elongation stress ratio in the longitudinal direction and the width direction at 100 ° C (higher numerical value / lower numerical value) of 1.05 to 1.60. 4. The molding polyester film according to any one of 4 above.   The polyester film for molding according to any one of claims 1 to 5, wherein the film has a thickness unevenness of 5.5% or less.   The film for molding according to any one of claims 1 to 6, wherein the film has a thermal shrinkage in the longitudinal direction and the width direction at 150 ° C of 3.0% or less.   The easily printable coating layer is (a) a polyester-based graft copolymer obtained by grafting an acid anhydride having at least one double bond to a hydrophobic copolymer polyester resin, and (b) an average particle size of 1.0. The molding polyester film according to claim 1, comprising a composition containing particles having a particle diameter of ˜5.0 μm.   The slippery coating layer is (c) a copolymer polyester resin, (d) a compound having a sulfonate group, (e) particles having an average particle size of 1.0 to 5.0 μm, (f) a polymer wax, The molding polyester film according to claim 1, comprising a composition containing   The polyester film for molding according to any one of claims 1 to 9, wherein the static friction coefficient and the dynamic friction coefficient when the easy-printing coating layer and the easy-sliding coating layer are superimposed are both 0.5 or less. .   A dummy container obtained from the molding polyester film according to claim 1.