WO2007094441A1 - Biaxially oriented polyester film for molding application - Google Patents

Abstract

[PROBLEMS] To provide a biaxially oriented polyester film for molding application, which has excellent mold release property and non-adhesive property and also has a molding processability. [MEANS FOR SOLVING PROBLEMS] The biaxially oriented polyester film comprises a polyester film and a coating layer laminated on at least one surface of the polyester film, wherein the coating film has a surface free energy of 15 to 35 mN/m. The coating layer also has a centerline average roughness of 1 to 50 nm. After the film is stretched in an arbitrary direction by two-fold, the centerline average roughness of the coating layer becomes 1 to 50 nm.

Description

 Specification

 Biaxially oriented polyester film for molding

 Technical field

 [0001] The present invention relates to a biaxially oriented polyester film for molding, and exhibits excellent releasability and non-adhesiveness after repeated use, high-temperature heat treatment, use after retort treatment, and use in a water atmosphere. In addition, the present invention relates to a film exhibiting stable performance with small variations and a method for producing the same. Further, the present invention relates to a film that does not change in surface condition before and after molding and exhibits excellent release properties and non-adhesive properties even after molding. For this reason, when it is pasted to a substrate, etc., and molded or the film itself is molded into a container, the contents are excellent in releasability and non-adhesiveness. It is suitable for food containers. In particular, a form used for the inner surface of a metal can which is molded after being laminated on a metal plate such as steel or aluminum is a very preferable embodiment.

 Background art

 [0002] Polyester films are used in a wide range of fields such as industrial materials, magnetic recording materials, optical materials, information materials, and packaging materials because of their excellent mechanical strength, thermal characteristics, humidity characteristics, and many other excellent characteristics. Used.

[0003] In recent years, polyester films have been widely used as containers or the like by taking advantage of their excellent characteristics and forming them after being bonded to a base material, or forming a polyester film itself. However, polyester has a problem that its molecular skeleton force is poor in releasability, and the contents adhere when used on the inner surface of a container or the like. In order to impart non-adhesiveness to the contents, a polyester film added with wax has been proposed (for example, Patent Document 1). However, in this proposal, since nitrogen is added at the time of polyester polymerization or wax master pellets are used, the nitrogen is not efficiently dispersed on the surface, and the non-adhesive effect is small. In addition, there has been proposed a film in which a polyester film surface is coated with silicone resin, fluorine-based resin, or the like to provide releasability (for example, Patent Document 2). However, since it is inferior in formability, it cannot be used for molding processing applications, and the performance is remarkably deteriorated when retort treatment is applied. There was a problem that when the molding process was performed, defects such as roughness and dents were generated on the surface.

 Patent Document 1: Japanese Patent Laid-Open No. 2001-220453

 Patent Document 2: Japanese Patent Application Laid-Open No. 2004-115566

 Disclosure of the invention

 Problems to be solved by the invention

[0004] An object of the present invention is to eliminate the above-mentioned problems of the prior art, exhibiting excellent non-adhesiveness even after high-temperature heat treatment and retort treatment, and forming biaxially oriented polyester film combined with molding processing Is to provide. Means for solving the problem

[0005] In order to solve the above problems, the biaxially oriented polyester film for molding of the present invention has the following constitution.

 (1) A coating layer having a surface free energy of 15 to 35 mNZ m is laminated on at least one side of the polyester film,

 The coating layer has a center line average roughness of 1 to 50 nm,

 A biaxially oriented polyester film for molding in which the center line average roughness of the coating layer after stretching the film twice in any direction at 23 ° C is 1 to 50 nm.

 (2) The contact angle of the coating layer with water is 90 to 120 °,

 And the contact angle with water after heat treatment at 180 ° C for 120 minutes is 90-120 °

 The biaxially oriented polyester film for molding described in (1).

 (3) The center line average roughness of the coating layer after stretching 1.5 times in any one direction of the film and in a direction perpendicular to the direction at 200 ° C. is 1 to 50 nm (1) or ( A biaxially oriented polyester film for molding as described in 2).

 (4) The biaxial alignment for molding according to any one of (1) to (3), wherein the surface free energy of the coating layer after the film is stretched twice in any direction at 23 ° C is 15 to 35 mNZm Polyester film.

(5) The biaxially oriented polyester film for molding according to any one of (1) to (4), wherein the coating layer is made of a silicone compound. (6) The biaxially oriented polyester film for molding according to (5), wherein the silicone compound strength is obtained by using a main agent and a crosslinking agent.

 (7) The biaxially oriented polyester film for molding according to (6), wherein an organopolysiloxane containing an alkenyl group as a main agent and a hydrodiene polysiloxane as a crosslinking agent are subjected to an addition reaction.

(8) The biaxially oriented polyester film for molding according to any one of (l) to (7), wherein the coating layer has a thickness of 0.01 to 3 _i um.

 (9) The contact angle between the coating layer and water when subjected to retort treatment at 125 ° C, 0.12 MPa and 90 minutes is 90 to 120 °, according to any one of (1) to (8) Biaxially oriented polyester eno refinolem for molding.

 (10) The biaxially oriented polyester oleorenolem for molding according to any one of (1) to (9), which has a melting point of 246 to 270 ° C.

 (11) At 100 ° C, the 100% elongation stress F100 value in any direction (A direction) of the film and the 100% elongation stress F100 value in the direction perpendicular to that direction (B direction)

A B

20 to each: The biaxially oriented polyester film for molding according to any one of (1) to (10), which is LlOMPa.

 (12) The biaxially oriented polyester film for molding according to any one of (1) to (11), which is used for bonding metal plates.

 (13) The biaxially oriented polyester film for molding according to any one of (1) to (12), which is used for container molding.

 (14) A method for producing the biaxially oriented polyester film for molding as described in (1), wherein the surface free energy of the coating surface is set to 47 mNZm or more, and then coated with an emulsion type coating agent. For producing biaxially oriented polyester film.

The invention's effect

Since the biaxially oriented polyester film for molding of the present invention has a large contact angle with water and low surface free energy, it is excellent in releasability and non-adhesiveness and can be used for various applications. In addition, high water contact angle after high temperature heat treatment that changes the surface roughness after molding Therefore, even after the film is formed or heat-treated, excellent release properties and non-adhesiveness can be maintained. Furthermore, it is preferably excellent in moldability and has a high water contact angle even after retort treatment, so that it can be used particularly for container molding applications such as food.

 BEST MODE FOR CARRYING OUT THE INVENTION

 [0007] The biaxially oriented polyester film for molding of the present invention is formed by laminating a coating layer on at least one side of a polyester film. By laminating the coating layer, the characteristics of the film surface can be improved efficiently.

 [0008] The method for laminating the coating layer in the present invention is not particularly limited, and an extrusion lamination method or a melt coating method may be used. For example, gravure coating, reverse coating may be used because a thin film can be coated at high speed. A method of laminating by spray coating, kiss coating, die coating or metering bar coating is preferably used. It is also possible to laminate a coating layer in-line, and if it is applied after longitudinal stretching in the middle of the film production process by the usual sequential biaxial stretching method, drying, heat treatment and lateral stretching are performed in the tenter. Favored ,.

 In the present invention, before the coating of the coating material, the film is subjected to surface activation treatment, such as corona discharge treatment, ozone treatment, ultraviolet treatment, sand mat processing, chemical treatment, etc. The surface free energy is preferably set to 47 mNZm or more, more preferably 50 mNZm or more, because it can improve the adhesion between the coating layer and the polyester film, and can eliminate coating defects. By improving the adhesion between the coating layer and the polyester film, the heat resistance, water resistance and retort resistance of the coating layer can be improved.

[0010] In the present invention, the surface free energy of the coating layer needs to be 15 to 35 mN / m from the viewpoints of releasability, non-adhesiveness, and handleability. If the surface free energy of the coating layer is greater than 35 mNZm, the releasability and non-adhesiveness are poor. Further, if the surface free energy is less than 15 mNZm, the film is not easily cut and processed, and the fulcrum in the case of laminating is not stable. A more preferred range of surface free energy is 17 to 33 mNZm, most preferably 20 to 30 mNZm. [0011] Further, in the biaxially oriented polyester film for molding of the present invention, the surface free energy of the coating layer after extending the film twice in an arbitrary direction at 23 ° C is 15 to 35 mNZm. is necessary. If the surface free energy of the coating layer after stretching the film twice in any direction is 15 to 35 mNZm, it can be molded after the film is bonded to the base material or after the film itself is molded. In addition, excellent properties can be exhibited in releasability and non-adhesiveness. The more preferred range of surface free energy after stretching the film in any direction, 2 times, is 17-33mNZm, most preferably 20-30mNZm! / ,.

 [0012] In the present invention, the contact angle of the coating layer with water is preferably 90 to 120 ° in terms of releasability, non-adhesiveness, and handleability. If the contact angle with water is in the above range, releasability, non-adhesiveness, and handleability can be compatible. If the contact angle with water is less than 90 °, the releasability and non-adhesiveness are poor. Also, if the contact angle with water is greater than 120 °, the film may be poorly cut and processed, and the fulcrum of the laminated sheet may not be stable. A more preferable range of the contact angle of the coating layer with water is 95 to 120 °, and 97 to 120 ° is most preferable.

 [0013] In the present invention, it is preferable that the contact angle between the coating layer and water when the heat treatment is performed at 180 ° C for 120 minutes is 90 to 120 °. If the contact angle between the coating layer and water after heat treatment at 180 ° C for 120 minutes is 90 to 120 °, it can be used for molding and food containers even after thermoforming and dry heat sterilization. Can be used.

 [0014] In order to set the contact angle after heat treatment at 180 ° C for 120 minutes within the above range, a coating compound with high heat resistance is used, or the adhesion between the polyester film and the coating compound is increased. It is preferable to improve or introduce a crosslinked structure into the coating composite.

 [0015] A more preferable range of the contact angle with water after heat treatment at 180 ° C for 120 minutes is 95 to 120 °, and most preferably 97 to 120 °.

[0016] In order to make the surface free energy of the coating layer and the contact angle with water within the above ranges, it is effective to include a water repellent compound in the coating layer. The composition constituting the coating layer may be composed only of a water-repellent compound, but may contain a resin, a solvent, water, a metal and the like as long as the characteristics of the present invention are not impaired. Coat water repellent compound By uniformly dispersing on the surface of the inging layer, the water contact angle and the surface free energy can be within the above ranges.

 [0017] Examples of the water-repellent compound include straight silicones such as dimethyl silicone, methyl phenol silicone, and methyl hydrogen silicone, amino groups, epoxy groups, carboxyl groups, carbinol groups, alkyl groups, poly groups on the side chain and Z or terminal. Silicone compounds such as modified silicone introduced with organic groups such as ether groups, natural waxes such as whale wax, beeswax, lanolin, carnauba wax, canderia wax, montan wax, rice wax, stearyl stearate, paraffin Wax compounds such as wax, microcrystalline wax, oxidized wax, ester wax, synthetic wax such as low molecular weight polyethylene, polytetrafluoroethylene, tetrafluoroethylene z perfluoroalkoxy Fluorine compounds such as a copolymer of ethylene and tetrafluoroethylene Z and ethylene, etc. are mentioned, but a silicone compound is preferred from the viewpoints of handleability, economy, heat resistance, and water repellent effect. Used.

 [0018] In the present invention, the silicone compound preferably used for the coating layer is preferably composed of a main agent and a crosslinking agent in terms of adhesion to a polyester film, water resistance, heat resistance, and the like. As the main agent, the above-mentioned silicone compound can be used. The main agent as used herein refers to a component that is contained most in the silicone compound based on mass.

[0019] The cross-linking agent is not particularly limited as long as it undergoes a cross-linking reaction with the main agent. For example, main agent: alkenyl group-containing Z cross-linking agent: Si-H bond-containing, main agent: silanol group or alkoxy Group-containing Z cross-linking agents: combinations containing alkoxy groups, hydroxyl groups such as acyloxy groups, main agents: hydroxyl group-containing Z cross-linking agents: containing isocyanate groups, etc. are preferably used. Among these, in terms of adhesion, heat resistance, water resistance, and retort resistance, silicone compounds obtained by addition reaction using organopolysiloxane containing alkenyl group as the main agent and hydrogenpolysiloxane as the cross-linking agent. Are preferably used. In this case, as an addition reaction catalyst, platinum compounds such as chloroplatinic acid, alcohol-modified chloroplatinic acid, chloroplatinic acid, vinyl siloxane complex, and rhodium compounds such as RhCl (Ph P) described in JP-A-4 352793 are used. It is preferable to add. [0020] Preferable amounts of the main agent and the crosslinking agent are 100 parts by weight of the main agent and 0.05 to 20 parts by weight of the cross-linking agent. More preferably, it is 0.1 to 15 parts by weight, and most preferably 0.1 to 10 parts by weight. In addition, the addition amount of the addition reaction catalyst is 0.0001 to 1 weight per 100 weight% of the main agent from the viewpoint of economical efficiency and catalytic effect. S preferred <, 0.0002 to 0.8 weight. More preferred is 0.005-0. 5 parts by weight.

 In the present invention, when forming the coating layer, it is preferable to prepare a coating composition containing the water-repellent compound and use this to form the coating layer. The form of the coating composition is not particularly limited, and examples thereof include an oil type, an emulsion type, a solution type, a baking type, a paste type, and a spray type. As used herein, the coating composition refers to a raw material composition when a coating layer is applied, and may include a component that volatilizes in a drying step or the like because of the composition before coating. A preferred coating composition is an emulsion type in terms of workability, economy, and handleability. The emulsion type coating composition can be used by diluting with water depending on the coating property. In addition, in order to further improve the coating properties, polybutyl alcohol polymers or derivatives thereof, cellulose conductors such as carboxymethyl cellulose and hydroxyethyl cellulose, etherified starches, starches such as dextrins, polybutylpyrrolidone, sulfoisophthalate. Water-soluble, such as copolymerized polyesters containing polar groups such as acids, butyl polymers such as polyhydroxyethyl methacrylate or copolymers thereof, acrylic polymers, urethane polymers, ether polymers A polymer compound or the like can be used in combination as a thickener. From the viewpoint of applicability, the preferred viscosity range is 5 to: LOOOmPa's, more preferably 10 to 800 mPa's, and most preferably 20 to 500 mPa's. The viscosity value here is measured based on JIS K-7117 and is at 23 ° C.

[0022] In addition, an organic solvent such as methanol, ethanol, isopropyl alcohol, benzene, hexane, heptane, or acetone is added in order to reduce the surface free energy of the coating composition and improve the coating property to the film. May be used. The surface free energy of the coating composition is preferably 30 to 60 mNZm from the viewpoints of coating properties and handling properties. The surface free energy of the coating composition is greater than 60mNZm In some cases, the coatability is inferior. In addition, if the surface free energy is less than 30 mNZm, it is necessary to add a large amount of an organic solvent having a small surface free energy, which is not preferable because the handling property is lowered. A more preferred range of surface free energy of the coating composition is 30-55 mNZm, with 35-50 mNZm being most preferred.

 [0023] When the viscosity of the coating composition is preferably U, the range is excellent even when the surface free energy is high, and conversely, when the surface free energy of the coating agent is within the preferable range, the viscosity is low. Since the coating property is excellent, the viscosity and surface free energy can be appropriately selected and adjusted according to the explosion-proof equipment in the coating process, the storage environment of the coating composition, and the like. By increasing the coating property, the effect of the water repellent compound is enhanced, and the contact angle with water and the surface free energy are reduced to the above ranges, which is very preferable.

 [0024] When a coating composition is prepared by adding a water-soluble polymer compound, an organic solvent, or the like, the preferred concentration of the water-repellent compound is in terms of uniform dispersibility, coatability, releasability and non-adhesiveness. The total coating composition is 100 to 60% by mass, and is 0.1 to 60% by mass, more preferably 0.5 to 50% by mass, and most preferably 1 to 40% by mass. When the concentration of the water repellent compound is high, the coatability and the uniform dispersibility may be inferior. Further, if the water repellent compound concentration is low, it may be inferior in releasability and non-adhesiveness.

 [0025] By making the concentration of the water repellency compound within the above-mentioned preferable range, it is efficiently dispersed on the surface of the coating layer, the contact angle with water is 90 to 120 °, and the surface free energy is 15 to 35 mNZm. Can be achieved.

 [0026] In the biaxially oriented polyester film for molding of the present invention, the center line average roughness of the coating layer is required to be 1 to 50 nm. Here, the centerline average roughness means a value obtained by folding the roughness curve with the centerline force and dividing the area obtained by the roughness curve and the centerline by the measurement length. In the present invention, five 5 cm × 5 cm samples are sampled in the width direction (250 mm) of the film, and each sample is evaluated.

[0027] As an evaluation method, for example, for each sample with a laser microscope, six points are extracted at equal intervals from the edge of the film, two-dimensional line roughness is measured, and the average value of the data is calculated as the centerline average roughness. (Average of 30 locations in total). In order to reduce the center line average roughness of the coating layer to less than 1 nm, it is necessary to reduce the center line average roughness of the polyester film before coating to less than 1 nm. Absent. That the center line average roughness of the coating layer is larger than 50 nm may mean that the coating layer is not uniformly applied, and the uneven coating after molding is a drawback. Even if the surface roughness after molding is within the preferable range, it may cause a major defect such as a dent, which may cause bad release and non-adhesiveness. Absent.

 In order to make the center line average roughness of the coating layer 1 to 50 nm, it is effective to smooth the coated surface of the polyester film to be coated. If the polyester film surface is not smooth, it is difficult to apply the coating layer uniformly, and the surface of the coating layer, which is a thin film, may also be affected. For this purpose, a method for reducing the particle content of the polyester film and a method for reducing the particle size of the particles to be used can be used within a range without impairing handling and properties. The handling property as used herein refers to film tearability, film transportability during coating, continuous processability during film formation, and the like. Specifically, the center line average roughness of the polyester film is adjusted so that the particle content in the polyester film before coating is less than 5% by mass, preferably less than 4% by mass, based on 100% by mass of the entire polyester film. Is effective because it can be reduced to 50ηm or less. However, if the particle content in the polyester film is less than 0.1% by mass, the center line average roughness of the polyester film may be less than lnm, which may reduce the handling of the film. . It is effective if the particle size used is 4 μm or less, preferably 2.5 μm or less. The particle diameter here means the number average diameter. The number average diameter can be obtained by the following formula.

 D = ∑DiZN (Di: equivalent circle diameter of particles, N: number of particles)

The particle size can be measured by, for example, using a scanning electron microscope or the like on the cross section of the film, observing 100 particles at a magnification of 100000 times, and using the observed image on an image analyzer or the like. Can be measured by capturing and analyzing images [0029] Further, by improving the uniform application property of the coating layer, the center line average roughness of the coating layer can be in the above range. In order to improve the uniform coatability of the coating layer, it is effective to set the surface free energy of the coating surface to 47 mNZm or more.

 [0030] Further, in this case, it is preferable to laminate the coating layer in-line. In this case, the coating composition is applied after the longitudinal stretching, and the coating layer is dried, heat-treated and laterally stretched in the tenter. It is stretched uniformly and is effective in bringing the average roughness of the center line of the coating layer into the above range.

 [0031] A more preferable range of the center line average roughness is 2 to 30 nm, and 3 to 20 nm is most preferable.

 [0032] Further, in the biaxially oriented polyester film for molding of the present invention, the center line average roughness of the coating layer after extending the film twice in an arbitrary direction at 23 ° C is 1 to 50 nm. is required. The center line of the coating layer after stretching the film twice in any direction means that the average roughness is greater than 50 nm, which means that the coating layer is roughened by stretching the film twice. This is not preferable because releasability and non-adhesiveness are lowered. Also, to make it less than lnm, it is necessary to make the center line average roughness of the film before molding less than Inm, which is not preferable because the handleability may be lowered. If the center line average roughness of the coating layer after stretching the film twice in any direction is 1 to 50 nm, the surface free energy of the coating layer after stretching twice can be maintained at 15 to 35 mNZm. This is very preferable because it can be done.

 [0033] A more preferable range of the center line average roughness of the coating layer after extending the film twice in an arbitrary direction at 23 ° C is 2 to 30 nm, and most preferably 3 to 20 nm.

[0034] The center line average roughness of the coating layer after the film was stretched twice was measured by cutting a film into a rectangular shape with a length of 150 mm and a width of 20 mm in one direction and the direction perpendicular to that direction. To make. Sampling is performed in 30 ° increments from any direction, and 6 samples are taken. Using a tensile tester (Orientec's Tensilon UCT-100), the initial tension chuck distance is 50 mm and the tensile speed is 300 mmZ. A tensile test is performed on the sample. For each sample (6 samples), use a sample that is 2 cm long x 1.5 cm wide from the center in the length direction. Is the value of each sample.

 [0035] With respect to six sets of samples sampled in 30 ° increments from one arbitrary direction, if the value of the centerline average roughness after double-stretching is included in the above range, measurement in a certain direction is possible. Even if the center line average roughness is outside the above range, the coating layer after film formation is not rough and can exhibit excellent characteristics.

 [0036] In order to make the center line average roughness of the coating layer after extending the film twice in an arbitrary direction at 23 ° C to 1-50nm, the coating layer has excellent adhesion and molding followability. It is effective. In order to improve the adhesion of the coating layer, it is effective to set the surface free energy of the coating surface of the film to 47 mNZm or more and to introduce a crosslinked structure in the coating layer.

 [0037] Further, in order to improve the molding followability, the thickness of the coating layer is preferably 0.01 to 3 / zm. Here, the thickness of the coating layer refers to the dry thickness after coating. If the coating layer is made 3 m or more, cracks may occur if the coating layer becomes rough during molding. Conversely, if the thickness of the coating layer is less than 0.01 μm, the characteristics of the coating layer may not be sufficiently exhibited, which is not preferable. The layer thickness of the coating layer can be adjusted by adjusting the solid content concentration of the coating composition or stretching the film after coating. For example, in the case of a metering bar coat, the thickness of the coating layer can also be adjusted by the count of the metal ring bar. A more preferable layer thickness of the coating layer is 0.05 to 1.5 m, and most preferably 0.1 to Lm.

[0038] Further, in order to improve the molding followability, it is important to appropriately control the heat treatment conditions after the coating layer is applied. If the heat treatment temperature is too low or the heat treatment time is too short, the adhesion and strength of the coating film may be lowered, resulting in poor molding followability. In addition, if the heat treatment temperature is too high or the heat treatment time is too long, the coating film becomes hard and may have a structure that is difficult to stretch, which may reduce the molding followability. A heat treatment temperature of 50-250 ° C is preferred 8 If it is 0-245 degreeC, in order to shorten the coating process more preferable, it is most preferable if it is 150-240 degreeC. The preferable heat treatment time varies depending on the heat treatment temperature, but is 1 to 120 seconds. If it is 2 to 60 seconds, 3 to 30 seconds is the most preferable from the viewpoint of more preferable economy.

 [0039] As described above, improving the adhesion between the coating layer and the film is also very important from the viewpoint of the molding followability of the coating layer.

 [0040] The biaxially oriented polyester film for molding of the present invention has a center line average roughness of the coating layer after stretching 1.5 times in any one direction of the film and in a direction perpendicular to the direction at 200 ° C. Is preferably 1 to 50 nm. At 200 ° C, the centerline average roughness of the coating layer after stretching 1.5 times in any one direction of the film and in the direction perpendicular to that direction is measured in any one direction and the direction perpendicular thereto. Measure the three combinations as follows: Set a film stretched to a size of 90 x 90 mm in one direction and perpendicular to that direction on a film stretcher heated to 200 ° C (manufactured by Toyo Seiki Seisakusho Co., Ltd.) for 20 seconds. After preheating, samples are prepared by stretching by biaxial stretching at a rate of 2000% Z in both directions at the same time in 1.5 times. Take 3 samples in 30 ° increments from any one direction, and extend for each sample as described above. From each sample (3 samples) central part, (arbitrary direction 10cm) X (direction perpendicular to it 10cm) Sample 10 samples and measure the center line average roughness at 10 locations for each sample to obtain the average value.

 [0041] (Arbitrary direction 10cm) X (In the direction perpendicular to it 10cm) Three samples sampled at 30 ° increments, centerline average roughness after stretching 1.5 X 1.5 times at 200 ° C If the thickness value is included in the above range, even if the centerline average roughness may be outside the above range in the measurement in a certain direction, the coating layer after film formation at high temperature Roughness is not seen, and excellent characteristics can be shown.

[0042] If the center line average roughness of the coating layer after stretching 1.5 times in any one direction of the film and in one direction perpendicular to the direction at 200 ° C is 1 to 50 nm, Even in high-temperature processing and molding, it is very preferable because it can exhibit excellent mold release and non-adhesive properties even after molding into various shapes that are difficult to roughen the coating layer. . When the average roughness of the coating layer after stretching 1.5 times in any one direction of the film and in the direction perpendicular to the direction at 200 ° C is greater than 50 nm, coating is performed during thermoforming. Roughness may occur in the layer, which is not preferable because the releasability and non-adhesiveness are lowered. In addition, in order to make it less than lnm, it is necessary to make the center line average roughness of the film before molding less than lnm.

 [0043] In order to make the center line average roughness of the coating layer after stretching 1.5 times in any one direction of the film and in a direction perpendicular to the direction at 200 ° C within the above range, It is very important to improve the adhesion and molding followability of the coating layer. In addition, it is preferable to use a coating compound having high heat resistance. When the heat resistance of the coating compound is low, the surface may be deformed and roughened by heat during molding at high temperature.

 [0044] Further, since the film is stretched in an arbitrary direction and a direction perpendicular to the direction, it is preferable that the film orientation is balanced. For example, if the film is significantly oriented in a certain direction, the film and the coating layer may be stressed when stretched in the oriented direction, resulting in a rough surface.

 [0045] The biaxially oriented polyester film for molding of the present invention has no problem whether the coating layer is laminated on only one side or laminated on both sides, but a metal plate, a resin sheet, paper, wood, etc. In the case of being used by bonding to the base material, the coating layer which is preferably laminated only on one side is preferably a surface which is not on the substrate side. When the coating layer is on the substrate side, it is not preferable because the adhesiveness to the substrate may be poor. By making the coating layer on the surface side, surface characteristics such as releasability and non-adhesiveness can be exhibited, which is a preferable mode.

[0046] In the present invention, the contact angle between the coating layer and water is preferably 90 to 120 ° when retort treatment is performed at 125 ° C, 0.12 MPa, and 90 minutes. When the retort treatment is performed at 125 ° C, 0.12 MPa for 90 minutes, the contact angle between the coating layer and water is 90-120 °, which means that the surface properties of the coating layer change before and after the retort treatment. It indicates that there is no. If there is no change in the surface properties of the coating layer before and after the retort treatment, for example, when the biaxially oriented polyester film for molding of the present invention is used for food containers. In this case, even after the retort treatment is performed as a sterilization treatment of the contents, the non-adhesiveness can be exhibited, so that the contents can be easily taken out. By exhibiting the resistance to retort treatment, the biaxially oriented polyester film for molding of the present invention is very preferable because applicable applications can be remarkably increased.

 [0047] In order to set the contact angle after the retort treatment in the above range, it is preferable to use a coating agent in combination with a crosslinking agent and introduce a crosslinked structure into the coating layer. .

 [0048] 125 ° C, 0.12 MPa, 90 minutes of retort heat treatment, better contact angle with water! / ヽ $ g¾i¾, 95-120 °, 97-120 ° Women's dress

[0049] The biaxially oriented polyester film for molding according to the present invention preferably has heat resistance, handling of resin, and properties from the viewpoint of power. The melting point is preferably 246 to 270 ° C. If the melting point is less than 246 ° C, the heat resistance is poor, and at 200 ° C, the surface becomes rough when stretched 1.5 times in any direction of the film and in the direction perpendicular to that direction. Since it may occur, it is not preferable. On the other hand, when the temperature is higher than 270 ° C., it may be inferior in adhesion to a base material such as a metal plate, a resin sheet, paper, or wood, which is not preferable. Here, the melting point of the biaxially oriented polyester film for forming of the present invention is the endothermic peak temperature that appears in the melting phenomenon when measured at a heating rate of 20 ° CZ using a differential scanning calorimeter (DSC). It is. When blending polyester rosin with different compositions and using it as a film, multiple endothermic peaks associated with melting may appear. In that case, the endothermic peak temperature that appears at the highest temperature is used as the molding temperature of the present invention. The melting point of the biaxially oriented polyester film. It is even more preferable if the melting point is 250-270 ° C. As a method of setting the temperature range that makes the melting point of the polyester film strong, it is preferable to set the melting point in the range of 246 to 270 ° C in the polyester resin stage used when forming the film. Even when using a resin, a polyester resin having a melting point of 246 ° C or higher is used. When a polyester resin is used with a low melting point, the resin used during melt-kneading is used. In order to suppress the melting point drop due to the transesterification reaction, the catalyst remaining in the resin in advance is deactivated, or a phosphorus compound is added to reduce the catalytic ability. Moreover, the melting point can be adjusted to a range of 246 to 270 ° C. by preparing a polyester resin having a low residual catalyst amount. [0050] From the viewpoint of moldability and handleability, the biaxially oriented polyester film for molding of the present invention has a stress F100 value at 100% elongation in any direction (A direction) of the film at 100 ° C.

 A

 And 100% elongation stress in the direction perpendicular to that direction (B direction)

 B

 ~: L is preferred to be lOMPa! /.

[0051] The polyester film of the present invention is 100. F100 value in C and F100 value that

 A B

 If each is 20 ~: L lOMPa, it is very excellent in moldability such as applying molding force after film is bonded to substrate or molding film itself. Therefore it is preferable.

 [0052] When the F100 value at 100 ° C and the F100 value force becomes larger than 10, the coating layer

 A B

 Even if the molding followability is good, the stress during molding becomes high, and the coating layer may be rough due to strain, which is not preferable. Conversely, with the film alone, the F100 value at 100 ° C and the F100 value are within the above range.

 A B

 Even if the film has good moldability, the F100 value of the biaxially oriented polyester film for molding of the present invention at 100 ° C and F100

 A B

 The value may not fall within the preferred range, and the surface may become rough.

[0053] If the F100 value and the F100 value are less than 20 MPa,

 A B

 The film surface may become rough when heat is applied, or the film may become too low and wrinkles may occur when the film is rolled up, or the handling may soon deteriorate. Therefore, it is not preferable.

 [0054] The biaxially oriented polyester film for molding of the present invention is excellent in the mold following ability of the coating layer in addition to the moldability of the single film, and therefore can be easily molded into various shapes, and the surface after molding. The releasability and non-adhesiveness can be maintained. In addition, because it holds the waist of the film, it is excellent in heat resistance and handling.

[0055] In the polyester film of the present invention, in order to set the stress at 100% elongation at 100 ° C in an arbitrary direction and a direction perpendicular thereto to 20 to: L LOMPa, it is produced by a preferred production method described later. It is preferable to do. In any direction, the FIOO value is most preferably 20 to: L lOMPa. However, in the present invention, the FIOO value is 20 to: L lOMPa. Even when there is a direction not shown, if there is at least one combination satisfying the F 100 value of 20 to: L 1 OMPa, excellent moldability is exhibited.

[0056] F100 value at 100 ° C and F100 value 20 to: L lOMPa

 A B

 As such, a method of controlling the orientation of the film according to the film forming conditions is preferably used. Furthermore, a method of controlling the melting point and glass transition point of the polyester used, and the copolymer composition and copolymerization ratio can also be preferably used. From the viewpoint of productivity, the method controlled by the film forming conditions is preferred, and in particular, it can be achieved by setting the stretching ratio, stretching temperature, and stretching speed during stretching within the preferable ranges in the film production method described later. is there.

 [0057] For example, the F100 value and the F100 value tend to decrease by decreasing the stretching ratio or increasing the preheating temperature and stretching temperature during stretching.

 A B

 [0058] The F100 value at 100 ° C and the F100 value are 30 to: LOOMPa is more preferable.

 A B

 Most preferred is 40 to 90 MPa.

 [0059] The biaxially oriented polyester film for molding of the present invention preferably has a film thickness of 5 to 100 µm in terms of moldability and handling properties. If the film thickness is less than 5 μm, the shape retention may be inferior. Also, if the film thickness exceeds 100 m, even if the deformation stress during thermoforming is reduced, the actual load increases, which may cause partial deformation or Since it takes time to raise the temperature, productivity may be reduced, which is not preferable. A more preferred range of film thickness is 8-50 / ζ πι, and most preferred is 10-30 m.

[0060] Here, the polyester resin constituting the biaxially oriented polyester film for molding of the present invention is a general term for polymer compounds having an ester bond as the main bond in the main chain, and is usually a dicarboxylic acid component. And a glycol component can be obtained by polycondensation reaction. Here, examples of the dicarboxylic acid component include terephthalic acid, isophthalic acid, phthalic acid, 2,6-naphthalenedicarboxylic acid, diphenyldicarboxylic acid, diphenylsulfone dicarboxylic acid, diphenoxyethanedicarboxylic acid, and 5-sodium. Aromatic dicarboxylic acids such as sulfoisophthalic acid, oxalic acid, succinic acid, adipic acid, sebacic acid, dimer acid, maleic acid, fumaric acid and other aliphatic dicarboxylic acids, cyclohexyne dicarboxylic acid, etc. Examples thereof include alicyclic dicarboxylic acids, and oxycarboxylic acids such as Poxybenzoic acid.

 [0061] Examples of the glycol component include ethylene glycol, 1,2 propanediol, 1,3 propanediol, 1,3 butanediol, 1,4 butanediol, 1,5 butanediol, and 1,6 hexanediol. , Aliphatic glycols such as neopentyl glycol, diethylene glycol, polyethylene glycol, polypropylene glycol

And polyoxyalkylene glycols such as polytetramethylene glycol, alicyclic glycols such as 1,4-cyclohexanedimethanol, and aromatic glycols such as bisphenol A and bisphenol S. Two or more of these dicarboxylic acid components and glycol components may be used in combination. The polyester used in the present invention may be a single polyester or a blend of two or more polyesters! /.

[0062] Particularly preferably used polyester is mainly composed of ethylene terephthalate which can be obtained by polycondensation reaction of terephthalic acid or dimethyl terephthalate and ethylene glycol by esterification reaction or transesterification reaction. It is preferable because of its excellent thermal characteristics and humidity characteristics. Note here, saying that main gutter Unowa, ethylene terephthalate component in the polyester is 30 mol _^0/0 or more

[0063] In the production of the polyester resin constituting the polyester film of the present invention, a reaction catalyst and a coloring inhibitor can be used. Examples of the reaction catalyst include alkali metal compounds, alkaline earth metal compounds, zinc compounds, lead compounds, manganese compounds, cobalt compounds, aluminum compounds, antimony compounds, titanium compound germanium compounds, and coloring inhibitors include phosphorus compounds. Although a compound etc. can be used, in this invention, it does not specifically limit to these.

[0064] Normally, it is preferable to add an antimony compound, a germanium compound, and Z or a titanium compound as a polymerization catalyst at any stage before the production of the polyester is completed. As such a method, for example, when a germanium compound is taken as an example, a method of adding a germanium compound powder as it is or a method of dissolving a germanium compound in a glycol component which is a starting material of polyester is used. To do it can.

 [0065] Examples of the germanium compounds that can be used include germanium dioxide, germanium hydroxide hydrate, germanium tetramethoxide, and germanium ethylene glycol oxide.

 Germanium alkoxide compounds, germanium phenoxide compounds, phosphoric acid-containing germanium compounds such as germanium phosphate and germanium phosphite, and germanium acetate can be used. Of these, germanium diacid germanium is preferably used.

 [0066] The antimony compound is not particularly limited. For example, oxides such as antimony trioxide and antimony acetate can be used. Further, the titanium compound is not particularly limited, but titanium tetraalkoxide such as titanium tetraethoxide and titanium tetrabutoxide can be preferably used.

 [0067] The biaxially oriented polyester film for molding of the present invention preferably contains particles having a number average particle diameter of 0.01 to 5 m from the viewpoint of improving handleability and preventing scratches during processing. The number average particle diameter is more preferably 0.05 to 4 μm from the viewpoint of prevention of scratches during heating and prevention of missing particles, and 0.1 to 3 / ζ πι is particularly preferable. As particles to be added, for example, internal particles, inorganic particles, and organic particles can be preferably used. In the biaxially oriented polyester film of the preferred V, embodiment of the present invention, the particles are preferably 0.01 to 5% by mass, more preferably 0.03 to 3% by mass, and still more preferably, with respect to the biaxially oriented polyester film. It can be contained in an amount of 0.05 to 2% by mass, particularly preferably 0.05 to 1% by mass. Further, as described above, when particles are added only to a specific layer as a laminated film, it is preferable that the particle concentration of the layer to which the particles are added is 0.01 to 5% by mass. A mass% is particularly preferred.

[0068] Examples of the method for precipitating the internal particles on the polyester film of the present invention include, for example, JP-A-48-61556, JP-A-51-12860, JP-A-53-41355, and JP-A-53-41355. The technique described in Japanese Patent Laid-Open No. 54-90397 can be employed. Furthermore, other particles described in JP-B-55-20496 and JP-A-59-204617 can be used in combination. [0069] The method for measuring the concentration of the contained particles is not particularly limited! However, for example, a solvent that dissolves the polyester and does not dissolve the inert particles is selected, and the inert particles are separated from the polyester by centrifugation. There is a method in which the mass of particles in the mass is used as the particle concentration. As the solvent, orthoclonal phenol, hexafluoroisopropanol, m-talesol and the like are preferably used.

 [0070] Examples of inorganic particles that can be contained in the polyester film of the present invention include wet and dry silica, colloidal silica, aluminum silicate, titanium oxide, calcium carbonate, calcium phosphate, barium sulfate, aluminum oxide, As organic particles such as My strength, kaolin, and clay, particles containing styrene, silicone, acrylic acid, methacrylic acid, polyester, divinyl compound, etc. as constituent components can be used. Among these, it is preferable to use inorganic particles such as wet and dry silica and alumina, and particles containing styrene, silicone, acrylic acid, methacrylic acid, polyester, divinylbenzene and the like as constituent components. In addition, use a combination of two or more of these internal, inorganic and organic particles.

 [0071] The method for producing the polyester film of the present invention is not particularly limited. For example, polyester resin is dried as necessary, and then supplied to a melt extruder, and a slit die is also extruded into a sheet. There is a method in which the unstretched sheet is stretched after being brought into close contact with a casting drum by cooling, solidifying and obtaining an unstretched sheet by a method such as electrostatic application.

 [0072] As a powerful stretching method, either simultaneous biaxial stretching or sequential biaxial stretching may be used. In other words, a method is employed in which an unstretched sheet is stretched and heat-treated in the longitudinal direction and the width direction of the film to obtain a film having a desired degree of plane orientation. Among these methods, the tenter method is preferred in terms of film quality, and then it is stretched in the longitudinal direction, followed by a sequential biaxial stretching method that extends in the width direction, or in the longitudinal direction and the width direction almost simultaneously. The simultaneous biaxial stretching method of stretching is preferably used to reduce variation in the plane orientation coefficient and to suppress uneven thickness.

[0073] In the intensive drawing method, the draw ratio employed is preferably 1.6 to 4.2 times, more preferably 2.4 to 4.0 times in each direction. In addition, it is desirable that the stretching speed is 100 to 200,000% Z min. Force that can be set to any temperature within a temperature range of + 100 ° C, preferably 80 to 170 ° C, particularly preferably 90 to 150 ° C in the longitudinal stretching temperature and stretching in the width direction. The temperature should be between 100 ° C and 150 ° C. In order to give the film a very good formability, it is particularly preferable to set the stretching temperature in the longitudinal direction to 100 to 130 ° C, particularly at a high temperature of 100 ° C or higher, especially before longitudinal stretching. : It is preferable to stretch after preheating for about LOO seconds in a range where it does not crystallize from the viewpoints of excellent flatness due to uniform stretching and excellent formability due to suppression of uneven orientation. Furthermore, the stretching may be performed a plurality of times in each direction.

 Furthermore, the film can be heat-treated after biaxial stretching. This heat treatment can be performed by any method such as in an oven or on a heated roll. The heat treatment temperature can be any temperature within the range of the stretching temperature to the melting point of the raw material, but is preferably a heat treatment temperature of 160 to 235 ° C. from the viewpoint of molding processability and impact resistance. If the temperature is lower than the temperature at which it is applied, the impact resistance may be poor, and if it is high, the molding cache property may be poor. In addition, the heat treatment time is preferably within 1 to 30 seconds without deteriorating other characteristics and within a range. Furthermore, heat treatment may be performed by relaxing the film in the longitudinal direction and the Z or width direction.

 [0075] Further, when the biaxially oriented polyester film for molding of the present invention is laminated with a coating layer with the inline as described above, in the above production method, after coating before stretching, A method of stretching or a method of stretching after uniaxially stretching in the longitudinal direction and then coating in the width direction can be used.

[0076] In the biaxially oriented polyester film for molding of the present invention, additives such as an antistatic agent, a thermal stabilizer, an antioxidant, a crystal nucleating agent, a weathering agent, and an ultraviolet absorber are impaired. It can be used to the extent that it is not. In addition, surface unevenness processing such as embossing force and sand matting, or surface treatment such as corona discharge treatment, plasma treatment, and alkali treatment may be performed as necessary. Furthermore, the biaxially oriented polyester film for molding of the present invention has an easy-adhesion treatment agent, an antistatic agent, a water vapor 'gas nolia agent (such as polysalt / vinylidene), a release agent, an adhesive, an adhesive, a flame retardant, an ultraviolet ray. Absorbents, matting agents, pigments, dyes, etc. can be coated or printed on aluminum, acid aluminum, silicon oxide, The purpose and method of vacuum deposition of a metal such as radium or a compound thereof for the purpose of light shielding, water vapor 'gas barrier, surface conductivity, infrared reflection and the like are not limited to the above.

 [0077] The biaxially stretched polyester film for molding of the present invention can be suitably used for molding processing. For example, the biaxially stretched polyester film for molding is subjected to molding processing from pasting to a base material, or the film itself is molded and processed. Can be used as In particular, since it is excellent in releasability and non-adhesiveness with respect to the contents, it can be suitably used as a metal plate laminating film strength film for storing food.

 Example

 [0078] (Physical property 'evaluation)

 The physical properties and characteristics of the polymer and film were measured and evaluated by the following methods.

 [0079] (1) Contact angle with water

 Using a contact angle meter (CA-D type manufactured by Kyowa Interface Chemical Co., Ltd.), the static contact angle with water was measured on a sample conditioned at 23 ° C and 65% RH for 24 hours. did. A sample size of lOcmX IOcm was used. The sample was measured 10 times, and the average value was taken as the contact angle of the sample.

 [0080] Further, the contact angle after the heat treatment was also measured in the same manner as described above. The heat treatment was performed by attaching the film to a 12 cm × 12 cm metal frame with double-sided tape and fixing it in a hot air oven at 180 ° C. for 120 minutes. Retort treatment is also fixed to the metal frame in the same way, and sterilized with 125. The test was performed under the conditions of C and 0.12 MPa for 90 minutes.

 [0081] After the heat treatment, the sample after the retort treatment was cut out to a size of 10 cm x 10 cm from the metal frame, measured 10 times each, and the average value was taken as the contact angle of the sample.

 [0082] (2) Surface free energy

In the same manner as in (1), the static contact angles with water, ethylene glycol, formamide, and methylene iodide were measured, and the following cubic equations were established using the surface tension components of each liquid in Table 1. (Measurement solutions for water, ethylene glycol, formamide, and methylene iodide were changed to 1, 2, 3, and 4, and L in Table 1 was replaced with 1, 2, 3, and 4). From this equation, numerical calculation Using software "Mathematica""FindMinimum" (command to find the local minimum value of a function consisting of complex numbers), find the γ ^d , γ °, γ ^h that gives the local minimum value. This was the surface free energy of the measured film surface.

[table 1]

0 θ

1/2 P \ 1/2 1/2 _, \ / n

 \ y 'y) + (y y y) + (y y y) ― y (1 + cos Θ) / 2

 3 3 3 3 3

 1/2 1/2 1/2 _, n \ / o

 (y'y) + (y'y) + (y'y)-y (1 + cos Θ) / 2.

 4 4 4 4 4

 [0085] (3) Double-stretching the film in any direction

 A sample was prepared by cutting a film into a rectangular shape having a length of 150 mm and a width of 20 mm in an arbitrary direction and a direction perpendicular to the direction. Similarly, sampling was performed in 30 ° C increments from any direction, and 6 samples were collected. Using a tensile tester (Orientec Tensilon UCT-100), the initial tensile chuck distance was 50 mm, the tensile speed was 300 mmZ, and each sample was subjected to a tensile test at 23 ° C and stretched 100%. The

[0086] (4) Stretch 1.5 times in any direction of the film and in the direction perpendicular to the direction

 A film stretched at 200 ° C (manufactured by Toyo Seiki Seisakusho Co., Ltd.) is placed in one direction and in a direction perpendicular to that direction, a film cut into a size of 90 X 90 mm is set, and preheating for 20 seconds Later, in both directions, the film was stretched by simultaneous biaxial stretching at a speed of 2000% Z at a time of 1.5 times. In addition, sampling was performed in 30 ° increments from one arbitrary direction, 3 samples were collected, and each sample was elongated.

 [0087] (5) Centerline average roughness

 Using an ultra-deep shape measuring microscope VK-8500 (manufactured by Keyence Corporation), the coating layer side two-dimensional line roughness was measured and calculated from the data. The measurement sample used was a sample of five 5 cm × 5 cm samples in the width direction of the film (250 mm). For each sample, 6 points were extracted at regular intervals from the edge of the film and measured (total of 30 points). The measurement was performed with an objective lens of 100 times, a measurement pitch of 0.01 m, a measurement length of 100 m, and a cutoff of 0.08 mm.

 [0088] The measurement of the center line average roughness of the coating layer after the film was stretched twice in an arbitrary direction was measured from the center in the length direction for each sample (6 samples) prepared in (3). Samples that were sampled to a length of 2 cm x a width of 1.5 cm were used, and each of 6 samples was extracted at 5 locations, and the average value was taken as the value of each sample.

[0089] In addition, the measurement of the centerline average roughness of the coating layer after stretching 1.5 times in any one direction of the film and in a direction perpendicular to the direction at 200 ° C was made in (4) Each sun Samples of (arbitrary direction 10cm) X (direction 10cm perpendicular to it) were sampled from the center of the pull (3 samples), and 10 samples were extracted for each sample, and the average value was taken as the value of each sample.

 [0090] (6) Coating layer thickness

 The cross section of the film was photographed with a transmission electron microscope (TEM H7100, manufactured by Hitachi, Ltd.) by an ultrathin section method, and the thickness of the coating layer was measured. The measurement was performed at an arbitrary 5 locations in the center in the film width direction at a magnification of 20000, and the average value was taken as the thickness of the coating layer.

 [0091] (7) Melting point of film

 Measurement was performed using a differential scanning calorimeter (Seiko Denshi Kogyo RDC220). If 5 mg of the sample is used as the sample and there are multiple endothermic peaks whose melting point is the endothermic peak temperature when the temperature is increased from 25 ° C to 300 ° C in 10 ° CZ minutes, the peak temperature of the endothermic peak on the highest temperature side The degree was taken as the melting point.

 [0092] (8) Stress at 100% elongation

 The film was cut into a rectangular shape with a length of 150 mm and a width of 10 mm in an arbitrary direction and a direction perpendicular thereto. Using a tensile tester (Orientec's Tensilon UCT-100), the initial tensile chuck distance was 50 mm, the tensile speed was 300 mmZ, and tensile tests were performed in the longitudinal and width directions of the film. For the measurement, a film sample was set in a constant temperature layer set to 100 ° C in advance, and a tensile test was performed after 90 seconds of preheating. Read the load applied to the film when the sample is stretched 100% (when the chuck-to-chuck distance is 100 mm), and the value divided by the cross-sectional area of the sample before the test (film thickness x 10 mm) is stretched by 100% Time stress (F100 value). The measurement was performed 5 times for each sample and in each direction, and the average value was evaluated.

 [0093] (9) Releasability

Using the method of (3), an acrylic adhesive tape (Nitto Denko Corporation Knit Polyester Tape 31B) with a width of 19 mm is applied to the coating layer surface of the film sample that has been stretched twice in any direction to a length of 200 mm. In this way, it was pressed with a rubber roller (linear pressure 2 kg / cm). This adhesive tape was peeled off at 25 ° C and 65% RH at a peeling angle of 90 °. Evaluated in quasi.

 Yu: I could peel off without any resistance.

 Good: Peeled almost without resistance.

 OK: I felt some resistance, but I could peel off without any problems.

 Impossible: I felt strong resistance and it was difficult to peel off.

 [0094] (10) Non-adhesive

 A film sample stretched 1.5 times in the longitudinal direction and width direction by the method of (4) is stored on an ABS sheet (200 X 300 mm) stored in a hot air oven at 200 ° C for 2 minutes via an adhesive sheet. After laminating the film with a laminator (180 ° C, lm / min, 0.3 MPa), placing it in a bat filled with commercially available minced meat, curing at 40 ° C and 65RH% for 72 hours, and then laminating the film The ABS sheet was taken out, and the amount (weight) attached to the film surface was judged according to the following criteria. The adhesive sheet was prepared by melt pressing (120 ° C, 4 MPa, lmin) (Nippon Synthetic Chemical Industry Co., Ltd. Polyester SP 170).

 Excellent: 0-10%

 Good: 10-30%

 Acceptable: 30-50%

 Impossible: 50-100%.

 [0095] (11) Formability

 A far-infrared heater heated to 200 ° C was used to heat the surface temperature to 180 ° C, and vacuum forming was performed using a cylindrical mold (bottom diameter 50 mm) to form a film. The state of being molded along the cylindrical mold was evaluated according to the following criteria using the degree of molding (drawing ratio: molding height Z bottom diameter).

 Excellent: Molding was possible at a drawing ratio of 0.5 or more.

 Good: Molding was possible at a drawing ratio of 0.5 to 0.3.

 Good: Molding was possible at a drawing ratio of 0.2 to 0.3.

 Not possible: tearing occurred and molding could not be performed with a drawing ratio of 0.2.

 [0096] (12) Handling

A 250mm wide film at a speed of 20mZmin, a core with a diameter of 100mm and a length of 400mm The ease of winding at that time was evaluated according to the following criteria to make it easy to handle. Yu: Wrinkles and wrinkles did not occur, and I was able to wind up without any problems.

 Good: The film was wrinkled and required immediate attention, but could be wound up without any problem. Good: Wrinkled film The film could be wound up without any problem.

 No A: The film slipped and could not be wound on the core.

 Impossible B: Wrinkles occurred in large quantities, and the film blocked.

 [0097] (Production method of polyester)

 The polyester resin used in the following examples and comparative examples was produced as follows.

 [0098] (PET)

 To a mixture of 100 parts by weight of dimethyl terephthalate and 70 parts by weight of ethylene glycol, 0.09 part by weight of magnesium acetate and 0.03 part by weight of antimony trioxide were added, and the temperature was gradually raised. Specifically, transesterification was performed while distilling methanol at 220 ° C. Subsequently, 0.020 part by mass of an 85% aqueous solution of phosphoric acid was added to the transesterification reaction product, and then transferred to a polycondensation reaction kettle. The reaction system was gradually depressurized while heating in the polymerization kettle, and the polycondensation reaction was carried out at 290 ° C under a reduced pressure of lhPa. The inherent viscosity was 0.65, and 2 mol% of the by-produced diethylene glycol was copolymerized. Polyethylene terephthalate resin was obtained.

[0099] (PBT)

 A mixture of 100 parts by mass of terephthalic acid and 110 parts by mass of 1,4 butanediol was heated to 140 ° C under a nitrogen atmosphere to obtain a homogeneous solution, and then 0.054 parts by mass of tetra-n-butyl orthotitanate, Esterification reaction was performed by adding 0.054 parts by mass of monohydroxybutyltin oxide. Next, 0.066 part by mass of tetra-n-butyl orthotitanate was added, and a polycondensation reaction was performed under reduced pressure to prepare polybutylene terephthalate resin having an intrinsic viscosity of 0.88. Thereafter, crystallization is performed at 140 ° C in a nitrogen atmosphere, followed by solid-phase polymerization at 200 ° C for 6 hours in a nitrogen atmosphere to obtain polybutylene terephthalate resin (PBT) having an intrinsic viscosity of 1.22. It was.

[0100] (PTT) 100 parts by weight of dimethyl terephthalate, 80 parts by weight of 1,3-propanediol using tetrabutyl titanate as a catalyst under nitrogen atmosphere, gradually increasing the temperature from 140 ° C to 230 ° C, while distilling methanol A transesterification reaction was performed. Furthermore, polycondensation resin having an intrinsic viscosity [7?] Of 0.86 was obtained by polycondensation reaction for 3 hours at a constant temperature of 250 ° C.

[0101] (PET— G)

To a mixture of 100 parts by weight of dimethyl terephthalate, 70 parts by weight of ethylene glycol, and 7 parts by weight of 1,4-cyclohexanedimethanol, add 0.04 parts by weight of manganese acetate. Conducted transesterification while distilling 220 ° C methanol. Next, 0.045 parts by mass of 85% aqueous phosphoric acid solution and 0.01 parts by mass of germanium dioxide were added, the temperature was gradually raised and reduced, and finally the temperature was raised to 275 ° C and lhPa, and the pressure was reduced. The polycondensation reaction is carried out until the degree reaches 0.67, and then discharged into a strand, cooled, and cut to obtain polyethylene terephthalate resin copolymerized with 4 mol% of 1,4-cyclohexanedimethanol. It was. The polyester resin was obtained by cutting the polymer into cubes having a diameter of 3 mm and performing solid-phase polymerization using a rotary vacuum polymerization apparatus under a reduced pressure of lhPa at 225 ° C until the intrinsic viscosity was 0.8. This was freeze-pulverized into a powder form, and 1,4-cyclohexanedimethanol 30 mol copolymerized polyethylene terephthalate (Eatster6763 manufactured by Eastman Chemical Co.) was uniformly mixed at 85:15. Then, 2 is supplied to the shaft vented extruder, melt-kneaded, cooled to Stra command shape extrusion, in water, and cut into chips 1, 4 Kisanjimetano Lumpur to Shikuro 7.9 mole _^0/0 both Polymerized PET-G was obtained.

[0102] (Particle Master)

In addition, 0.04 parts by mass of manganese acetate was added to a mixture of 100 parts by mass of dimethyl terephthalate and 70 parts by mass of ethylene glycol, and the temperature was gradually raised. Finally, methanol was distilled at 220 ° C for transesterification. Reaction was performed. Next, 0.025 parts by mass of 85% phosphoric acid aqueous solution and 0.02 parts by mass of germanium dioxide were added. Further, add ethylene glycol slurry of wet silica agglomerated particles with an average particle size of 2.2 m so that the particle concentration becomes 2% by mass, gradually increase and decrease the pressure, and finally 290 ° C, The temperature is raised to lhPa, the pressure is reduced, and the polycondensation reaction is performed until the intrinsic viscosity becomes 0.63, and then discharged into a strand, cooled, and cut To obtain a particle master.

 [0103] (Method for producing coating composition)

 The coating composition used in the following experiments was prepared as follows.

[0104] (Coating composition A)

 Alkenyl group-containing organopolysiloxane / hydrogen polysiloxane-attached silicone-reacted silicone emulsion (X-52-195), 100 parts by weight, catalyst (CAT-PM-10), manufactured by Shin-Etsu Silicone Co., Ltd. 5 parts by mass, 100 parts by mass of isopropyl alcohol, and 400 parts by mass of water were mixed to obtain a coating composition A.

[0105] (Coating composition B)

 Alkal group-containing organopolysiloxane / hydrogen polysiloxane-attached silicone-reacted silicone emulsion (X—52—195), 100 parts by weight, catalyst (CAT—PM—10), manufactured by Shin-Etsu Silicone Co., Ltd. 3 parts by mass, polyvinyl alcohol QP-18) 5 mass% aqueous solution manufactured by Nippon Vinegar Poval Co., Ltd. was mixed with 300 parts by mass to obtain a coating composition B.

[0106] (Coating composition C)

 Alkal group-containing organopolysiloxane / hydrogen polysiloxane-attached silicone-reacted silicone emulsion (X—52—195), 100 parts by weight, catalyst (CAT—PM—10), manufactured by Shin-Etsu Silicone Co., Ltd. 1 part by mass, 200 parts by mass of isopropyl alcohol, and 1000 parts by mass of water were mixed to obtain a coating composition C.

[0107] (Coating composition D)

 100 parts by mass of silicone emulsion (SILCOLEASE902) manufactured by Arakawa Chemical Industries, Ltd., 10 parts by mass of catalyst (CATA903), and 600 parts by mass of water were mixed to obtain a coating composition D.

 [0108] (Coating composition E)

 Alkale group-containing organopolysiloxane manufactured by Toray Dow Cowing Silicone Co., Ltd.

A coating composition E was obtained by mixing 100 parts by mass of Z hydrogendiene polysiloxane-attached silicone reaction purged (LTC750A), 1 part by mass of catalyst (SRX-212) and 500 parts by mass of toluene.

[0109] (Coating composition F) The coating composition F was acrylic emerald (Nifengsol Y-9105) manufactured by Nippon Carbide Industries Co., Ltd.

[0110] (Coating composition G)

 A coating composition G was prepared by mixing 100 parts by mass of Shin-Nakamura's long-chain alkyl acrylate (TR-7) with 60 parts by mass of water.

[0111] (Coating composition H)

 A coating composition H was prepared by mixing 100 parts by mass of Shin-Nakamura's long chain alkyl acrylate (TR-7), 50 parts by mass of water and 20 parts by mass of isopropyl alcohol.

[0112] (Coating composition I)

 A coating composition I was obtained by mixing 100 parts by mass of a wax emulsion (KEK-T) manufactured by Guangei Chemical Industry Co., Ltd., 20 parts by mass of isopropyl alcohol, and 150 parts by mass of water.

[0113] (Coating composition J)

 Wax emulsion (KEK-T) manufactured by Guangei Chemical Industry Co., Ltd. was used as coating composition J.

 [0114] (Coating composition K)

 On the other hand, 100 parts by mass of a non-silicone emulsion type back release agent (Pyroleel 40 6) manufactured by Ogyo Fat Industries Co., Ltd. and 500 parts by mass of water were mixed to obtain a coating composition K.

 [0115] (Example 1)

 PET and particle master were mixed at a mass ratio of 99: 1, dried at 180 ° C for 4 hours in a vacuum dryer, and after sufficiently removing water, supplied to a single screw extruder, melted at 280 ° C, After removal and leveling of the extrusion amount, the sheet was discharged from a T-die onto a cooling drum whose temperature was controlled at 25 ° C. At that time, a wire-like electrode having a diameter of 0.1 mm was applied electrostatically and adhered to a cooling drum to obtain an unstretched film.

[0116] Next, the film temperature was raised with a heating roll before stretching in the longitudinal direction, and finally the film was stretched 3.0 times in the longitudinal direction at a film temperature of 105 ° C, and the temperature was immediately controlled to 40 ° C. Cooled with a metal roll. This uniaxially stretched film was subjected to corona discharge treatment in air, and the surface free energy of the polyester film was set to 52 mNZm. The treated surface was coated with coating composition A using a metalling bar (# 6). Next, the tenter type Stretched 3.0 times in the width direction at a pre-heating temperature of 95 ° C and a stretching temperature of 120 ° C with a horizontal stretching machine, and while maintaining a 4% relaxation in the width direction in the tenter for 5 seconds at a temperature of 210 ° C. Heat treatment was performed to obtain a biaxially oriented polyester film in which a coating layer having a film thickness of 15 μm was laminated.

 [0117] (Example 2)

 Example except that PET and particle master were mixed at a mass ratio of 97: 3, coating composition B was used, and the draw ratio in the longitudinal direction was 3.1 times and the draw ratio in the width direction was 3.1 times. In the same manner as in 1, a biaxially oriented polyester film on which a coating layer having a film thickness of 12 μm was laminated was obtained.

 [0118] (Example 3)

 The same procedure as in Example 2, except that coating composition G was used, the film temperature during stretching in the longitudinal direction was 95 ° C, the stretching ratio was 3.1 times, and the stretching ratio in the width direction was 3.2 times. A biaxially oriented polyester film with a 20 μm thick coating layer

[Example 4]

 PET, PBT, and particle master are mixed at a mass ratio of 77: 20: 3, dried in a vacuum dryer at 180 ° C for 3 hours to sufficiently remove moisture, then supplied to a single screw extruder, melted at 280 ° C After removing foreign substances and leveling the amount of extrusion, the product was discharged in a sheet form from a T-die onto a cooling drum whose temperature was controlled at 25 ° C. At that time, a wire-like electrode having a diameter of 0.1 mm was applied electrostatically and adhered to the cooling drum to obtain an unstretched film.

[0120] Next, before stretching in the longitudinal direction, the film temperature was raised with a heating roll, and finally, the film was stretched 3.0 times in the longitudinal direction at a film temperature of 100 ° C and immediately heated to 40 ° C. Cooled with a controlled metal roll. This uniaxially stretched film was subjected to corona discharge treatment in air, and the surface free energy of the polyester film was set to 52 mNZm. The treated surface was coated with coating composition E using a metalling bar (# 6). Next, it was stretched 3.0 times in the width direction at a preheating temperature of 95 ° C and a stretching temperature of 110 ° C with a tenter-type horizontal stretching machine, and the temperature was maintained at 230 ° C while relaxing 4% in the width direction in the tenter. A biaxially oriented polyester film having a film thickness of 15 μm was obtained by heat treatment at C for 5 seconds. [0121] (Example 5)

 PET, PET-G and particle master are mixed at a mass ratio of 16: 80: 4, dried in a vacuum dryer at 180 ° C for 4 hours, and after sufficiently removing moisture, supplied to a single screw extruder, 280 ° C After being melted at, removal of foreign matter and leveling of the amount of extrusion were performed, and then discharged from a T-die onto a cooling drum whose temperature was controlled at 25 ° C. At that time, electrostatic application was performed using a wire electrode having a diameter of 0.1 mm, and the film was brought into close contact with the cooling drum to obtain an unstretched film.

 [0122] Next, before stretching in the longitudinal direction, the film temperature was raised with a heating roll, and finally, the film was stretched 3.0 times in the longitudinal direction at a film temperature of 100 ° C and immediately heated to 40 ° C. Cooled with a controlled metal roll. This uniaxially stretched film was subjected to corona discharge treatment in air, and the surface free energy of the polyester film was set to 52 mNZm. The treated surface was coated with coating composition I using a metalling bar (# 10). Next, it was stretched 3.0 times in the width direction at a preheating temperature of 95 ° C and a stretching temperature of 110 ° C with a tenter type horizontal stretching machine, and the temperature was 220 ° while relaxing 4% in the width direction in the tenter. Heat treatment was performed at C for 5 seconds to obtain a biaxially oriented polyester film having a film thickness of 12 μm.

 [0123] (Example 6)

 PET and particle master were mixed at a mass ratio of 97: 3, dried in a vacuum dryer at 180 ° C for 4 hours, after sufficiently removing moisture, supplied to a single screw extruder, melted at 280 ° C, After removal and leveling of the extrusion amount, the sheet was discharged from a T-die onto a cooling drum whose temperature was controlled at 25 ° C. At that time, a wire-like electrode having a diameter of 0.1 mm was applied electrostatically and adhered to a cooling drum to obtain an unstretched film.

Next, the film temperature is raised with a heating roll before stretching in the longitudinal direction, and finally the film is stretched 3.1 times in the longitudinal direction at a film temperature of 105 ° C. Then, the preheating temperature is 95 with a tenter type transverse stretching machine. The film is stretched 3.1 times in the width direction at a temperature of 110 ° C and stretched at 110 ° C, and heat treated for 5 seconds at a temperature of 210 ° C while relaxing 4% in the width direction in the tenter. A μm biaxially oriented polyester film was obtained. This biaxially oriented polyester film was subjected to corona discharge treatment in air, the surface free energy was set to 54 mNZm, and coating composition E was coated using a metalling bar (# 8) in a hot air dryer at 120 ° C. The biaxially oriented polyester film is dried for 60 seconds and laminated with a coating layer Got.

 [0124] (Example 7)

 PET and particle master were mixed at a mass ratio of 99.8: 0.2, and coating composition H was used, except that the draw ratio in the longitudinal direction was 3.3 times and the draw ratio in the width direction was 3.2 times. In the same manner as in Example 1, a biaxially oriented polyester film on which a coating layer having a film thickness of 12 m was laminated was obtained.

[0125] (Example 8)

 PET, PBT, PTT, and particle master are mixed at a mass ratio of 67: 15: 15: 3, and coating composition K is used. The stretching temperature in the longitudinal direction is 100 ° C, the stretching temperature in the width direction is 110 ° C, A biaxially oriented polyester film in which a coating layer having a film thickness of 20 m was laminated was obtained in the same manner as in Example 1 except that the heat treatment temperature was 240 ° C.

[0126] (Example 9)

 Biaxially oriented polyester with a coating layer with a film thickness of 15 m laminated in the same manner as in Example 1 except that PET and particle master were mixed at a mass ratio of 99.6: 0.4 and coating composition C was used. A film was obtained.

[Example 10]

 Laminate a coating layer with a film thickness of 15 m in the same manner as in Example 8 except that PET, PBT, PTT, and particle master were mixed at a mass ratio of 69: 20: 10: 1 and coating composition B was used. A biaxially oriented polyester film was obtained.

[0128] (Example 11)

 Biaxially laminated PET / PBT and particle master at a mass ratio of 67: 30: 3 and a coating layer with a film thickness of 12 / zm as in Example 8 except that coating composition D was used. An oriented polyester film was obtained.

[Example 12]

 Biaxial orientation in which PET, PTT, and particle master were mixed at a mass ratio of 68: 30: 2 and a coating layer with a film thickness of 15 m was laminated in the same manner as in Example 8 except that coating composition G was used. A polyester film was obtained.

[0130] (Comparative Example 1) PET frozen in a powder form and carnauba wax are mixed at a mass ratio of 98: 2, mixed uniformly, then fed to a twin-screw vent type extruder, melt-kneaded, extruded into a strand, and extruded in water. After cooling, the wafer was cut into chips to obtain a wax master chip.

 [0131] PET, carnauba wax master, and particle master were mixed at a mass ratio of 47: 50: 3, dried in a vacuum dryer at 180 ° C for 4 hours to remove water sufficiently, and then a single screw extruder. , Melted at 280 ° C, removed foreign matter, and leveled the amount of extrusion, and discharged from a T-die onto a cooling drum controlled at 25 ° C. At that time, a wire-like electrode having a diameter of 0.1 mm was applied electrostatically and adhered to the cooling drum to obtain an unstretched film.

 [0132] Next, before stretching in the longitudinal direction, the film temperature was raised with a heating roll, and finally the film temperature was stretched 3.3 times in the longitudinal direction at 95 ° C and immediately heated to 40 ° C. Cooled with a controlled metal roll. Next, it was stretched 3.3 times in the width direction at a preheating temperature of 90 ° C and a stretching temperature of 100 ° C with a tenter-type transverse stretching machine, and the temperature was maintained at 230 ° C while relaxing 4% in the width direction in the tenter. A heat treatment was carried out at C for 5 seconds to obtain a biaxially oriented polyester resin having a film thickness of 12 μm.

 [0133] (Comparative Example 2)

 PET and particle master were mixed at a mass ratio of 97: 3, dried at 180 ° C for 4 hours in a vacuum dryer to sufficiently remove moisture, then supplied to a single screw extruder, melted at 280 ° C, After removal and leveling of the extrusion amount, the sheet was discharged from a T-die onto a cooling drum whose temperature was controlled at 25 ° C. At that time, a wire-like electrode having a diameter of 0.1 mm was applied electrostatically and adhered to a cooling drum to obtain an unstretched film.

[0134] Next, the film temperature was raised with a heating roll before stretching in the longitudinal direction, and finally the film was stretched 3.3 times in the longitudinal direction at a film temperature of 95 ° C and immediately controlled to 40 ° C. Cooled with a metal roll. Next, it was stretched 3.3 times in the width direction at a preheating temperature of 90 ° C and a stretching temperature of 100 ° C with a tenter-type transverse stretching machine, and the temperature was maintained at 230 ° C while relaxing 4% in the width direction in the tenter. A biaxially oriented polyester film having a film thickness of 15 μm was obtained by heat treatment at C for 5 seconds. This biaxially oriented polyester film was subjected to corona discharge treatment in air, the surface free energy was set to 54 mNZm, the coating composition J was coated using a metalling bar (# 5), and hot air at 120 ° C was applied. Dry in the dryer for 60 seconds, A biaxially oriented polyester film laminated with a single layer was obtained.

 [0135] (Comparative Example 3)

 A biaxially oriented polyester film in which a coating layer having a film thickness of 15 m was laminated was obtained in the same manner as in Example 4 except that the coating composition F was used.

 [0136] (Comparative Example 4)

 PET and particle master are mixed at a mass ratio of 94: 6, and coating composition B is used. The stretching ratio in the longitudinal direction is 3.3 times, the stretching temperature is 100 ° C, and the stretching ratio in the width direction is 3.2 times. A biaxially oriented polyester film in which a coating layer having a film thickness of 15 m was laminated was obtained in the same manner as in Example 1 except that.

 [0137] (Comparative Example 5)

 After PET is dried at 180 ° C for 4 hours in a vacuum dryer to sufficiently remove moisture, it is supplied to a single screw extruder, melted at 280 ° C, foreign matter is removed, and the amount of extrusion is leveled. The sheet was discharged from a T-die onto a cooling drum whose temperature was controlled at 25 ° C. At that time, a non-stretched film was obtained by applying a static electricity using a wire electrode having a diameter of 0.1 mm and closely contacting the cooling drum.

 [0138] Thereafter, Example 1 was used except that the coating composition J was used, except that the stretching ratio in the longitudinal direction was 3.0 times, the stretching temperature was 100 ° C, and the stretching ratio in the width direction was 3.8 times. Similarly, a biaxially oriented polyester film in which a coating layer having a film thickness of 15 m was laminated was obtained.

[0139] [Table 2]

[ε 挲] [owo]

808ZSO / .OOZdf / X3d LZ \ ttt6QILmZ OAV

808ZS0 / .00Zdf / X3d 68 1 60 / M 00 OAV

[0142] * Surface free energy and centerline average roughness after 2 times elongation were measured for 6 samples stretched in any direction, and only the maximum and minimum values were listed. ** 5 X 1.5 Centerline average roughness after stretching by 5 times is measured for three sets of samples stretched in an arbitrary direction and in a direction perpendicular thereto, and only the maximum and minimum values are listed. did.

 * * *: ^ And F100 are three sets of extension in any direction and the direction perpendicular to it.

 A B

 Samples were measured and only the maximum and minimum values were listed. Industrial applicability

[0143] Since the biaxially oriented polyester film for molding of the present invention has a large contact angle with water and low surface free energy, it is excellent in releasability and non-adhesiveness, and should be used for various applications. Can do. In addition, it has excellent moldability and exhibits excellent mold release and non-adhesive properties after molding, high temperature heat treatment, and retort treatment, so it can be used for container molding applications such as foods.

Claims

The scope of the claims

 [1] A coating layer with a surface free energy of 15 to 35 mNZm is laminated on at least one side of the polyester film,

 The coating layer has a center line average roughness of 1 to 50 nm,

 A biaxially oriented polyester film for molding in which the center line average roughness of the coating layer after stretching the film twice in any direction at 23 ° C is 1 to 50 nm.

[2] The contact angle of the coating layer with water is 90 to 120 °,

 And the contact angle with water after heat treatment at 180 ° C for 120 minutes is 90-120 °

 The biaxially oriented polyester film for molding according to claim 1.

[3] The center line average roughness of the coating layer after stretching 1.5 times in any one direction of the film and in a direction perpendicular to the direction at 200 ° C. is 1 to 50 nm. 2. A biaxially oriented polyester film for molding described in 1.

[4] The biaxially oriented polyester phenolic for molding according to claim 1, wherein the surface free energy of the coating layer after stretching the film twice in an arbitrary direction at 23 ° C is 15 to 35 mNZm.

 [5] The biaxially oriented polyester polyester for molding according to claim 1, wherein the coating layer is made of a silicone compound.

 6. The biaxially oriented polyester film for molding according to claim 5, wherein the silicone compound comprises a main agent and a crosslinking agent.

[7] Silicone compound strength Organopolysiloxane containing alkell group as main ingredient

7. The biaxially oriented polyester film for molding according to claim 6, wherein a hydrodiene polysiloxane is subjected to an addition reaction as a crosslinking agent.

[8] The biaxially oriented polyester film for molding according to [1], wherein the coating layer has a thickness of 0.01 to 3 μm.

 [9] The biaxially oriented polyester film for molding according to claim 1, wherein the contact angle between the coating layer and water is 90 to 120 ° when retort treatment is performed at 125 ° C, 0.12 MPa, and 90 minutes. .

[10] The biaxially oriented polyester film for molding according to claim 1, having a melting point of 246 to 270 ° C.

[11] Stress at 100% elongation at 100 ° C in any direction (A direction) FlOO value and

 A

 And 100% elongation stress in the direction perpendicular to that direction (B direction)

 B

 The biaxially oriented polyester film for molding according to claim 1, which is L: LOMPa.

[12] The biaxially oriented polyester phenolic for molding according to claim 1, which is used for bonding metal plates.

 13. The biaxially oriented polyester film for molding according to claim 1, which is used for container molding.

[14] The method for producing a biaxially oriented polyester film for molding according to claim 1, wherein the coating surface is coated with an emulsion type coating agent after the surface free energy of the coating surface is set to 47 mNZm or more. A method for producing a characteristic biaxially oriented polyester film for molding.