JP2008088410A - Surface protective polyester film for molding - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To allow the beauty of the appearance after molding to be maintained, by protecting the surface during the molding of a decorative sheet for molding and a decorative film for molding. <P>SOLUTION: Disclosed is a surface protective film for molding which has stress (an F100 value) of 1-70 MPa as measured when the film is extended by 100% in the longitudinal direction and in the width direction of the film at 150°C and 200°C, and has elongation of 200-800%. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a molding polyester film, and more particularly to a molding protective surface film that can be suitably used for a molding decorative sheet, a surface protective film at the time of molding a molding decorative film, and the like. .

  In recent years, there has been a growing demand for low environmental impacts such as solventless coating and hexavalent chromium replacement in the field of automotive parts, electronic equipment, and building materials, and decoration of molded parts using decorative sheets for molding and decorative films for molding. Introduction of methods is in progress. In these members, the appearance is very important, and it is necessary to finish the surface state of the molded member beautifully.

  As a decorative molding method using a decorative sheet and a decorative film, a method of performing pre-molding such as vacuum molding, vacuum pressure forming, plug assist molding, etc., and then injecting a resin is often used. However, in this case, there is a problem that the surface is scratched or the glossiness of the surface is lowered in a severe molding process such as heating, pushing up the mold, and vacuuming. For this reason, the proposal which laminates | stacks the masking film which can be heat-molded is made (for example, refer patent document 1).

  However, this proposal is a non-oriented urethane film in which the masking film is cast directly on the decorative sheet, the film has too low rigidity, the peelability after molding, and the surface condition of the decorative sheet after molding is insufficient. In addition, after a step of injecting a resin, peeling after molding was very difficult.

Further, as a metallic easy-to-mold decorative sheet, a molding laminate in which a mask layer is laminated has been proposed to prevent scratches during molding (see, for example, Patent Document 2). Here, a highly stretched film made of polyester, nylon, polyurethane or the like is proposed as a mask layer. However, in this proposal, the stress at the time of molding is not sufficiently low, so when molding a laminate for molding, the molding followability is insufficient, and the peelability after molding is poor, so metallic easy molding There was a problem that fragments of the protective film remained on the surface of the decorative sheet.
JP-T-2001-514984 US 06/565955

  An object of the present invention is to eliminate the above-described problems. That is, it aims at maintaining the beauty of the appearance after molding by protecting the surface of the molded sheet during molding.

The present invention has the following configuration. That is,
(1) Surface-protecting polyester film for molding process having a stress at 100% elongation (F100 value) of 1 to 70 MPa and an elongation of 200 to 800% in the film longitudinal direction and the width direction at 150 ° C and 200 ° C,
(2) The surface-protecting polyester film for molding process according to (1), which is a biaxially oriented film.
(3) Polyethylene terephthalate-based resin A and polybutylene terephthalate-based resin and / or polyester-based resin B selected from the group consisting of polytrimethylene terephthalate-based resin, with 100% by mass of the entire film, Surface-protective polyester film for molding process according to (1) or (2), comprising a polyester-based resin composition in which ~ 90% by mass and resin B are mixed at 90 to 10% by mass,
(4) The resin B includes a polybutylene terephthalate resin b1 and a polytrimethylene terephthalate resin b2, and the total amount of the resin b1 and the resin b2 is 100% by mass, and the resin b1 is 10 to 90% by mass. The surface-protecting polyester film for molding according to any one of (1) to (3), wherein b2 is mixed at 90 to 10% by mass,
(5) The surface-protecting polyester film for molding according to any one of (1) to (4), which is used by being laminated on the surface of the decorative sheet for molding,
(6) The surface-protecting polyester film for molding according to any one of (1) to (4), which is used by being laminated on the surface of the decorative film for molding,
(7) A laminate for molding in which the surface-protecting polyester film for molding processing according to any one of (1) to (4) is used by being laminated on the surface of the decorative sheet for molding,
(8) A molded laminate in which the surface-protecting polyester film for molding processing according to (6) is laminated on the surface of the decorative film for molding,
(9) A molding method for a molded member in which the molding laminate according to (7) or (8) is pre-molded and trimmed, and then a resin is injected and the surface-protecting polyester film for molding processing is peeled off,
(10) A molding member obtained by molding the molding laminate according to (7) or (8) and then peeling the surface-protecting polyester film for molding processing, wherein the molding decoration before molding A molded member having an absolute value of the difference in glossiness of the surface between the sheet and the decorative film for molding of less than 10;
It is.

  The protective polyester film for molding according to the present invention protects the surface of the decorative sheet for molding or the decorative film for molding during molding, thereby maintaining the beauty of the appearance after molding and molding with an excellent appearance. A member can be produced.

  The surface protective polyester film for molding in the present invention is a decorative sheet for molding in order to prevent scratches on the surface or a decrease in gloss when molding a decorative sheet for molding or a decorative film for molding. Or the thing of the polyester film laminated | stacked on the surface of the decorative film for shaping | molding is pointed out.

  The surface protective polyester film for molding according to the present invention is 100% stretched in the longitudinal direction and the width direction at 150 ° C. and 200 ° C. from the point of followability during molding of the decorative sheet for molding and the decorative film for molding. The time stress (F100 value) needs to be 1 to 70 MPa.

  The processing step of the decorative sheet for molding and the decorative film for molding includes a step of thermoforming such as vacuum forming, pressure forming, and plug assist forming after a preheating step using an infrared heater or the like. In these steps, the temperature in the molding apparatus is set to 150 ° C. to 200 ° C., but since it is difficult to make the temperature uniform, local deformation due to temperature spots may occur. In order to suppress this local deformation, it is necessary that the deformation stress is sufficiently lowered at 150 ° C., and that the stress level is maintained up to 200 ° C.

  That is, the surface protective polyester film for molding process of the present invention has an F100 value of 1 to 70 MPa in the film longitudinal direction and the width direction at 150 ° C. and 200 ° C., so that it has excellent moldability and local deformation due to temperature spots. It has been found to prevent.

  If the stress at 100% elongation (F100 value) at 150 ° C. and 200 ° C. is less than 1 MPa, the film cannot be withstood in the preheating step in the molding process, and the film is deformed, and sometimes breaks. May not be used as a protective film. On the other hand, if it exceeds 70 MPa, deformation during thermoforming is insufficient, and the follow-up to the decorative sheet for molding and the decorative film for molding is so sweet that it cannot be used as a protective film. From the viewpoint of handleability and molding followability, the 100% elongation stress (F100 value) in the film longitudinal direction and width direction at 150 ° C. and 200 ° C. is preferably 3 to 50 MPa, and most preferably 5 to 30 MPa.

  Moreover, the surface protection polyester film for molding process of the present invention is the elongation in the film longitudinal direction and the width direction at 150 ° C. and 200 ° C. from the viewpoint of moldability during processing of the decorative sheet for molding and the decorative film for molding. Needs to be 200 to 800%. As described above, the processing step of the decorative sheet for molding and the decorative film for molding is difficult to make the temperature uniform, so at 150 ° C. or 200 ° C. to prevent local breakage and deformation of the film during molding. A sufficient elongation of 200 to 800% is also necessary.

  If the elongation is less than 200%, the film may not be able to withstand the molding processing magnification of the molded sheet, and the film may be broken, and may not be used as a protective film. Also, the design of a film exceeding 800% is not preferable because it is not economical and may have poor heat resistance. In terms of formability, heat resistance, and economy, the elongation in the film longitudinal direction and the width direction is preferably 250 to 700%, and most preferably 300 to 600%.

  Here, the stress at 100% elongation (F100 value) and elongation of the film at 150 ° C. and 200 ° C. in the present invention will be described. Stress at 100% elongation when a film sample cut into a rectangular shape with a test length of 50 mm is preheated for 90 seconds in a constant temperature layer set at 150 ° C. or 200 ° C. and then subjected to a tensile test at a strain rate of 300 mm / min. The elongation value was defined as 100% elongation stress (F100 value), and the elongation rate of the film when the film was ruptured.

  In the polyester film of the present invention, the stress and elongation at 100% elongation of the film at 150 ° C. and 200 ° C. are within the above ranges as follows: 2 at a temperature of 90 to 130 ° C. in the longitudinal direction and the width direction of the film. It is preferable that the surface magnification (longitudinal direction draw ratio × width direction draw ratio) is 7 to 11 times. The stretching temperature can be appropriately changed depending on the raw material used, but the higher the stretching temperature, the more preferable the orientation is suppressed. Furthermore, it is preferable to set the heat treatment temperature before stretching to be equal to or higher than the stretching temperature because the orientation is further suppressed. Moreover, in the heat setting process after extending | stretching, it is preferable at the point which relaxes the orientation by extending | stretching by making heat processing temperature high. The preferred temperature range is 200-250 ° C, more preferably 210-245 ° C, most preferably 220-240 ° C. Furthermore, the polyester used preferably comprises a polyethylene terephthalate resin (A) and a polyester resin (B) selected from polybutylene terephthalate resin and / or polytrimethylene terephthalate resin.

  Here, the polyethylene terephthalate resin (A) is a resin having 100 mol% polyethylene terephthalate as a constituent component, or a copolymer component of less than 30 mol%, preferably less than 20 mol%, is copolymerized with polyethylene terephthalate. This resin is composed of polyethylene terephthalate (however, diethylene glycol by-product is excluded as a copolymer component). As the copolymerization component to polyethylene terephthalate, 1,2-propanediol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexane Aliphatic dihydroxy compounds such as diol and neopentyl glycol, polyoxyalkylene glycols such as polyethylene glycol, polypropylene glycol and polytetramethylene glycol, alicyclic dihydroxy compounds such as 1,4-cyclohexanedimethanol, bisphenol A, bisphenol S and the like Aromatic dihydroxy compounds, etc., but 1,3-propanediol, 1,4-butanediol, neopentyl glycol, and 1,4-cyclohexanedimethanol are preferably used in terms of moldability and handleability. It is. Preferred dicarboxylic acid components include aromatic dicarboxylic acids such as 2,6-naphthalenedicarboxylic acid, isophthalic acid, diphenyldicarboxylic acid, diphenylsulfonedicarboxylic acid, diphenoxyethanedicarboxylic acid, 5-sodiumsulfonedicarboxylic acid, and phthalic acid. , Oxalic acid, succinic acid, adipic acid, sebacic acid, dimer acid, maleic acid, fumaric acid and other aliphatic dicarboxylic acids, 1,4-cyclohexanedicarboxylic acid and other alicyclic dicarboxylic acids, paraoxybenzoic acid and other oxycarbons An acid etc. can be mentioned. The dicarboxylic acid ester derivatives include esterified products of the above dicarboxylic acid compounds, such as dimethyl terephthalate, diethyl terephthalate, 2-hydroxyethyl methyl terephthalate, dimethyl 2,6-naphthalenedicarboxylate, dimethyl isophthalate, and dimethyl adipate. In addition, diethyl maleate, dimethyl dimer, and the like can be mentioned, but 2,6-naphthalenedicarboxylic acid and isophthalic acid are preferably used in terms of moldability and handleability. The polyethylene terephthalate resin (A) includes a resin (a1) made of 100 mol% polyethylene terephthalate not containing a copolymer component and a polyethylene terephthalate resin (a2) containing less than 20 mol% of a copolymer component. Further, it may be composed of two or more types of polyethylene terephthalate resins. Further, the polyethylene terephthalate resin (a1) may contain less than 30 mol of a copolymer component, and the polyethylene terephthalate resin (A) may be blended with three or more kinds of polyethylene terephthalate resins.

  The polyester-based resin (B) selected from polybutylene terephthalate resin and polytrimethylene terephthalate resin is a resin and / or 100 mol% polytrimethylene terephthalate containing 100 mol% polybutylene terephthalate as a constituent component. Or a polyester obtained by copolymerizing a polybutylene terephthalate and / or polytrimethylene terephthalate with a copolymer component of less than 20 mol%, preferably less than 10 mol%. Alternatively, a polybutylene terephthalate resin and a polytrimethylene terephthalate resin may be mixed and used. Examples of the copolymer component to the polyester resin (B) include ethylene glycol, 1,2-propanediol, 1,3-butanediol, 1,5-pentanediol, 1,6-hexanediol, neopentyl glycol, and the like. Aliphatic dihydroxy compounds, polyoxyalkylene glycols such as polyethylene glycol, polypropylene glycol and polytetramethylene glycol, alicyclic dihydroxy compounds such as 1,4-cyclohexanedimethanol, aromatic dihydroxy compounds such as bisphenol A and bisphenol S, etc. Is mentioned. Preferred dicarboxylic acid components include aromatic dicarboxylic acids such as 2,6-naphthalenedicarboxylic acid, isophthalic acid, diphenyldicarboxylic acid, diphenylsulfonedicarboxylic acid, diphenoxyethanedicarboxylic acid, 5-sodiumsulfonedicarboxylic acid, and phthalic acid. , Oxalic acid, succinic acid, adipic acid, sebacic acid, dimer acid, maleic acid, fumaric acid and other aliphatic dicarboxylic acids, 1,4-cyclohexanedicarboxylic acid and other alicyclic dicarboxylic acids, paraoxybenzoic acid and other oxycarbons An acid etc. can be mentioned. The dicarboxylic acid ester derivatives include esterified products of the above dicarboxylic acid compounds, such as dimethyl terephthalate, diethyl terephthalate, 2-hydroxyethyl methyl terephthalate, dimethyl 2,6-naphthalenedicarboxylate, dimethyl isophthalate, and dimethyl adipate. , Diethyl maleate, dimethyl dimer, and the like.

  The polyester film of the present invention is selected from a polyethylene terephthalate-based resin (A), a polybutylene terephthalate-based resin, and a polytrimethylene terephthalate-based resin from the viewpoint of molding conformability of the molding decorative sheet or the molding decorative film. The polyester resin (B) is a polyester resin composition in which the resin (A) is mixed in an amount of 10 to 90% by mass and the resin (B) in an amount of 90 to 10% by mass on the basis of the whole film. A film is preferred. When the resin (A) exceeds 90% by mass, the effect of improving moldability that is manifested by mixing with the resin (B) is not recognized. Conversely, when the resin (B) exceeds 90% by mass, the crystallization rate of the resin Becomes too fast, the film-forming property, particularly the stretchability is deteriorated, and whitening due to crystallization becomes remarkable. As a mixing ratio of the resin (A) and the resin (B), film formation stability is obtained if the resin (A) is 40 to 90% by mass and the resin (B) is 60 to 10% by mass, based on the entire film. It is more preferable in terms of heat resistance and moldability, and it is particularly preferable if the resin (A) is 60 to 90% by mass and the resin (B) is 40 to 10% by mass.

  Further, the resin (B) is composed of a mixture containing a polybutylene terephthalate resin (b1) and a polytrimethylene terephthalate resin (b2), and is composed of the resin (A), the resin (b1), and the resin (b2). Since orientation and crystallization during stretching are suppressed, molding followability with a molded sheet is improved, which is very preferable. Here, the mixing ratio of the polybutylene terephthalate resin (b1) and the polytrimethylene terephthalate resin (b2) is 10 to 90 mass of the resin (b1) based on the total amount of the resin (b1) and the resin (b2). % And the resin (b2) are preferably mixed at 90 to 10% by mass. More preferably, the resin (b1) is mixed at 30 to 70% by mass and the resin (b2) at 70 to 30% by mass, the resin (b1) is 40 to 60% by mass and the resin (b2) is 60 to 40% by mass. It is particularly preferable if it is mixed in%.

  The polyester film of the present invention preferably has a melting point of 210 to 270 ° C. from the viewpoints of heat resistance and dimensional stability. When the melting point is less than 210 ° C., the heat resistance is inferior, and when the thermoforming or the like is performed, the film surface becomes rough due to heat loss, and after molding the decorative sheet for molding and the decorative film for molding, When the protective film is peeled off, the glossiness may decrease. On the other hand, if the melting point exceeds 270 ° C., the melting point becomes too high, and the molding followability during thermoforming may be inferior. From the viewpoints of both heat resistance and moldability, the melting point is preferably 220 to 265 ° C, and more preferably 246 to 255 ° C. Here, the melting point of the polyester film is an endothermic peak temperature that is manifested by a melting phenomenon when measured with a differential scanning calorimeter (DSC) at a heating rate of 20 ° C./min. When a polyester resin having a different composition is blended and used as a film, a plurality of endothermic peaks due to melting may appear.In this case, the endothermic peak temperature appearing at the highest temperature is the melting point of the polyester film of the present invention. And

  As a method of setting the temperature range to apply the melting point of the polyester film, it is preferable to set the melting point in the range of 210 to 270 ° C. in the polyester resin stage used when forming the film, and even when using a polyester resin having a different composition. In order to suppress a melting point drop due to a transesterification reaction between resins during melt kneading even when using a polyester resin having a melting point of 210 ° C. or higher and blending a polyester resin having a low melting point In order to deactivate the catalyst remaining in the resin in advance or to reduce the catalytic ability, a phosphorus compound is added. Moreover, melting | fusing point can be made into the range of 210-270 degreeC by preparing the polyester resin with a low residual catalyst amount.

  Since the surface protective polyester film for molding process of the present invention is intended to be used as a decorative sheet for molding or a protective film at the time of molding process of the decorative film for molding, from the point of film shape maintenance at the time of molding, The film thickness before molding is preferably 10 to 250 μm. If the film thickness exceeds 250 μm, no matter how much the deformation stress at the time of thermoforming is reduced, the actual load will increase, so there may be partial deformation, and it takes time to raise the temperature for the forming process. This may reduce productivity. Furthermore, as preferable film thickness, it is 12-100 micrometers, and it is especially preferable in it being 18-50 micrometers.

  The surface-protecting polyester film for molding according to the present invention is intended to improve the appearance of a molded article produced using the decorative sheet for molding after molding and the decorative film for molding. The center line average roughness is preferably 1 to 30 nm. When the center line average roughness is larger than 30 nm, the surface roughness may be transferred to the molded product, which may be undesirable in appearance such as a reduction in glossiness. Further, if the center line average roughness is less than 1 nm, handling properties such as film conveyance and winding processes are deteriorated, and scratches may occur on the film surface. A more preferable range of the center line average roughness is 2 nm to 25 nm, and most preferably 3 nm to 20 nm.

  The method for achieving the above surface condition is not particularly limited, but can be achieved by appropriately controlling the particle size and particle size distribution of the particles contained in the film. The method for containing the particles is not particularly limited. For example, the particles are compounded in advance with a polyester resin, and the particle master is mixed at a predetermined concentration at the time of film formation. And the like. Although it does not specifically limit as particle | grains to be used, Organic particles and inorganic particles can also be used. Examples of the organic particles include crosslinked polystyrene, crosslinked acrylic resin, melamine resin, and benzoguanamine resin. As the inorganic particles, for example, silica, colloidal silica, beaded silica, alumina, alumina sol, kaolin, talc, mica, clay, calcium carbonate, metal oxide (such as tin oxide) and the like are preferably used. These organic particles and inorganic particles preferably have a spherical monodisperse shape in order to achieve both handleability and surface roughness. Further, as the size of the particles, the number average particle diameter is preferably 0.001 to 6 μm, more preferably 0.01 to 3 μm, and most preferably 0.05 to 1.5 μm. In order to prevent the particles from falling off, the particles are preferably contained in the base polyester film.

  Further, the content of the particles is not particularly limited, but the entire polyester film is 100% by mass, 0.001 to 5% by mass, more preferably 0.003 to 3% by mass, and still more preferably 0.005 to 2%. It can be contained by mass%, particularly preferably 0.01 to 1 mass%.

  Next, a specific method for producing the surface-protecting polyester film for molding according to the present invention will be described.

  Regarding the polyester resin used in the present invention, commercially available polyethylene terephthalate resin and polybutylene terephthalate resin and copolymers thereof can be purchased and used. For example, in the case of polyethylene terephthalate resin, as follows: Can be polymerized.

  To a mixture of 100 parts by weight of dimethyl terephthalate and 70 parts by weight of ethylene glycol, 0.09 parts by weight of magnesium acetate and 0.03 parts by weight of antimony trioxide are added, the temperature is gradually raised, and finally Performs transesterification while distilling methanol at 220 ° C. Next, 0.020 parts by mass of an 85% aqueous solution of phosphoric acid is added to the transesterification reaction product, and then the mixture is transferred to a polycondensation reaction kettle. The reaction system is gradually depressurized while heating in the polymerization kettle, and a polycondensation reaction is performed at 290 ° C. under a reduced pressure of 1 hPa to obtain a polyethylene terephthalate resin having a desired intrinsic viscosity, for example, an intrinsic viscosity of 0.65. it can.

  Polybutylene terephthalate and polytrimethylene terephthalate can be similarly polymerized. For example, in the case of polybutylene terephthalate, a mixture of 100 parts by mass of terephthalic acid and 110 parts by mass of 1,4-butanediol is added in a nitrogen atmosphere. Then, the mixture is heated to 140 ° C. to obtain a homogeneous solution, and 0.054 parts by mass of tetra-n-butyl orthotitanate and 0.054 parts by mass of monohydroxybutyltin oxide are added to carry out an esterification reaction. Subsequently, 0.066 parts by mass of tetra-n-butyl orthotitanate is added and a polycondensation reaction is performed under reduced pressure to obtain a polybutylene terephthalate resin having a desired intrinsic viscosity, for example, an intrinsic viscosity of 0.9. it can.

  A preferred method for producing the film of the present invention using the polyester resin obtained as described above will be specifically described.

First, the polyethylene terephthalate resin (A) to be used and the polybutylene terephthalate resin (b1) and / or the polytrimethylene terephthalate resin (b2) are weighed and mixed at a predetermined ratio as necessary. Drying is performed in a nitrogen atmosphere or a vacuum atmosphere before or after mixing. It is preferable that the moisture content in the resin after drying is 50 ppm or less. Then, the mixed polyester resin is supplied to a single screw or twin screw extruder and melt extruded. Next, foreign matter is removed and the amount of extrusion is leveled through a filter and a gear pump, respectively, and discharged from the T die onto a cooling drum in a sheet form. At that time, an electrostatic application method in which a cooling drum and the resin are brought into close contact with each other by static electricity using an electrode applied with a high voltage, a casting method in which a water film is provided between the casting drum and the extruded polymer sheet, and the casting drum temperature is set to be equal to that of the polyester resin. The sheet-like polymer is brought into close contact with the casting drum, cooled and solidified by a method of sticking the extruded polymer at a glass transition point to (glass transition point−20 ° C.) or a combination of these methods, and unstretched. Get a film. Among these casting methods, when using polyester, a method of applying an electrostatic force is preferably used from the viewpoint of productivity and flatness.
Although the film of the present invention exhibits excellent moldability even when used without stretching, it is preferably a biaxially oriented film from the viewpoint of heat resistance because it is used as a protective film during thermoforming. It is preferable to use a biaxially oriented film in order to improve easy peelability when the molded sheet is peeled off after being formed. The biaxially oriented film is obtained by stretching an unstretched film in the longitudinal direction and then stretching in the width direction, or by stretching in the width direction and then stretching in the longitudinal direction, or by the longitudinal direction of the film. It can be obtained by stretching by a simultaneous biaxial stretching method in which the width direction is stretched almost simultaneously.

  As a draw ratio in such a drawing method, preferably 2.5 to 3.5 times, more preferably 2.8 to 3.5 times, and particularly preferably 3 to 3.4 times are employed in each direction. The The stretching speed is preferably 1,000 to 200,000% / min. The stretching temperature is preferably 90 to 130 ° C, more preferably 100 to 120 ° C in the longitudinal direction and 90 to 110 ° C in the width direction. Further, the stretching may be performed a plurality of times in each direction.

  Furthermore, the film is heat-treated after biaxial stretching. The heat treatment can be performed by any conventionally known method such as in an oven or on a heated roll. This heat treatment is performed at a temperature of 120 ° C. or higher and below the melting point of the polyester, but is preferably 200 to 250 ° C. The heat treatment time can be arbitrarily set within a range not deteriorating the characteristics, and is preferably 1 to 60 seconds, more preferably 1 to 30 seconds. Further, the heat treatment may be performed by relaxing the film in the longitudinal direction and / or the width direction. Furthermore, in order to improve the adhesive force with the ink print layer, the adhesive, and the vapor deposition layer, at least one surface can be subjected to corona treatment or a coating layer can be provided.

  The surface-protecting polyester film for molding processing of the present invention may be a single layer film or a laminated film having two or more A / B layers. In the case of a three-layer structure of A / B / C, it is preferable that the polyester constituting the C layer is the same as the polyester constituting the A layer from the viewpoint of economy and productivity. Furthermore, in order to improve economy and productivity, it is preferable to make the laminated thickness of the A layer and the C layer equal.

  Moreover, it is preferable that the surface protection polyester film for shaping | molding processing of this invention is laminated | stacked and used on the surface of the decoration sheet for shaping | molding or the decoration film for shaping | molding. After laminating on the surface of the decorative sheet for molding or the decorative film for molding, forming them as a single body is preferable because it can suppress scratches on the surface after molding and decrease in glossiness.

  Here, the decorative sheet for molding refers to a moldable sheet having a decorative function and having a thickness of 250 μm or more. Generally, it is often composed of a base sheet / decorative layer / surface layer. On the other hand, the decorative film for molding refers to a moldable film of less than 250 μm having a decorative function. In this case, the film itself may have a decorating function as a single film layer, or a layer having a decorating function may be provided on a transparent film so that the thickness is less than 250 μm.

  Although it does not specifically limit as a structure of the decorating sheet for shaping | molding, It is preferable that it is the structure by which the decorating layer was laminated | stacked on the base material sheet. Moreover, it is a preferable aspect to laminate | stack a clear layer on a decoration layer in order to provide a weather resistance, a scratch resistance, etc. In addition, when the base sheet itself has a decoration function such as black, white, or metallic, a structure in which a clear layer is laminated directly on the base sheet is also sufficient as a decorative sheet. This is a preferred configuration because it creates value.

  Although it does not specifically limit as a base material of the decorating sheet for shaping | molding, A resin sheet, a metal plate, paper, wood, etc. are mentioned. Among these, a resin sheet is preferably used in terms of moldability, and a thermoplastic resin sheet is preferably used in terms of high moldability.

  Here, the thermoplastic resin sheet is not particularly limited as long as it is a polymer sheet that can be thermoformed. However, an acrylic sheet, an ABS (acrylonitrile-butadiene-styrene) sheet, a polystyrene sheet, an AS (acrylonitrile-styrene) sheet. , TPO (Thermo Plastic Olefin elastomer) sheet, TPU (Thermo Plastic Urethane elastomer), etc. are preferably used. The thickness of the sheet is 50 μm to 2000 μm, more preferably 100 μm to 1500 μm, and still more preferably 250 to 1000 μm.

  The resin used for the clear layer is not particularly limited as long as it is a highly transparent resin, but a polyester resin, a polyolefin resin, an acrylic resin, a urethane resin, a fluorine resin, or the like is preferably used. Among these, it is preferable that an acrylic resin or a fluorine resin is contained in terms of weather resistance. Also, a mixture of these resins may be used. For example, a polyvinylidene fluoride dispersion dispersed in polymethyl methacrylate is preferably used. Further, the lamination thickness of the clear layer is preferably 10 to 100 μm, more preferably 15 to 80 μm, and most preferably 20 to 60 μm from the viewpoint of weather resistance and handleability.

  The decorative layer used in the decorative sheet for molding is a layer for adding decoration such as coloring, unevenness, pattern, wood grain, metal tone, pearl tone and the like. When the decorative sheet for molding is used and the molded body is finally manufactured, the molded body is decorated. Although the layer which mix | blended the coloring agent with the printed matter and resin, and a metal vapor deposition layer are mentioned, it is not limited to this.

  Moreover, it does not specifically limit as a formation method of a decoration layer, For example, it can form by printing, a coating, transfer, metal vapor deposition, etc. As a particularly preferable method for forming the decorative layer, there is a method in which a carrier film or the like in which a colorant is dispersed in a resin is coated and transferred to a substrate. Examples of the resin used at this time include polyester resins, polyolefin resins, acrylic resins, urethane resins, and fluorine resins. Although it does not specifically limit as a coloring agent to be used, Considering dispersibility etc., it selects suitably from dye, an inorganic pigment, an organic pigment, etc. As the dispersion resin, for example, a polyvinylidene fluoride dispersion dispersed in polymethyl methacrylate is preferably used in the same manner as the clear layer.

  In the case of metal vapor deposition, the method for producing the vapor deposition film is not particularly limited, but vacuum vapor deposition, EB vapor deposition, sputtering, ion plating, and the like can be used. In order to improve the adhesion between the polyester film and the vapor deposition layer, the vapor deposition surface is preferably pretreated by a method such as a corona discharge treatment or an anchor coating agent. As the metal used, it is preferable to deposit a metal compound having a melting point of 150 to 400 ° C. from the viewpoint of molding followability. The use of a metal in the melting point range is preferred because the polyester film can be molded in a temperature range and the deposited metal layer can be molded, and it is easy to suppress the occurrence of a deposited layer defect due to molding. The melting point of a more preferable metal compound is 150 to 300 ° C. Although it does not specifically limit as a metal compound whose melting | fusing point is 150-400 degreeC, Indium (157 degreeC) and tin (232 degreeC) are preferable, and indium can be used especially preferable. The lamination thickness of the decorative layer is preferably 0.001 to 100 μm, more preferably 0.01 to 80 μm, and most preferably 0.02 to 60 μm.

  Moreover, making a clear layer, a decoration layer, and a base material with the same or similar composition as a preferable aspect is also mentioned. Such a configuration is preferable because the decorative sheet can be recovered and used without being separated into respective layers after use. For example, since TPO is preferably used as the base material, if a decorative sheet for molding in which the clear layer and the decorative layer are made of an olefin resin is used, the sheet is pre-molded and the remaining trimmed Since the portion can be recovered as it is and reused, it is a very preferable configuration from the viewpoint of low environmental load.

  The method for setting the clear layer is not particularly limited, but there are a method for directly coating the clear layer on the thermoplastic resin sheet (base material), a method for transferring the clear layer to the thermoplastic resin sheet (base material), and the like. Can be mentioned. After the clear layer resin is laminated on the carrier film and dried, it can be transferred to a thermoplastic resin sheet (base material). Furthermore, when installing a decoration layer, after laminating a decoration layer on a clear layer, a decoration layer / clear layer can be transcribe | transferred to a thermoplastic resin sheet (base material). The carrier film used here is not particularly limited, but when laminating a clear layer or a clear layer / decorative layer, heat may be applied at about 100 to 200 ° C. to dry the film, which is excellent in heat resistance. It is preferable that From the viewpoint of heat resistance and economy, a polyester film such as a polyethylene terephthalate film or a polyethylene naphthalate film, or a copolymer polyester film containing a copolymer component therein is preferably used.

  Moreover, in order to improve adhesiveness with a thermoplastic resin sheet (base material), it is preferable to provide an adhesive layer in a clear layer or a decoration layer. Although it does not specifically limit as an adhesive layer, What added the crosslinking agent to urethane type, acrylic type, and a chlorinated polypropylene type resin is used preferably. As the crosslinking agent, an epoxy system is preferably used from the viewpoint of adhesiveness. Furthermore, it is also preferable to install a primer layer such as an acrylic resin in order to increase the adhesion between the clear layer or the decorative layer and the adhesive layer.

  Although the decorative film for molding in the present invention is not particularly limited, it is preferable in terms of simplifying the number of steps if the film itself has a decorative function. For example, a colored film, a metal tone film, a pearl tone film, etc. are mentioned. In recent years, high value-added films have been developed, and many films having a decorating function have been developed. Although the decorative film for molding is composed of a resin, the resin used is not particularly limited. For example, polyolefin resin, polyester resin, acrylic resin, polycarbonate resin and the like can be mentioned. The colored film mentioned here can be colored by kneading a pigment or dye into the film and coloring it, or by coating a colored layer. In addition, the metallic tone film is made to exhibit a metallic tone by depositing a metal compound by a vacuum deposition method, an EB deposition method, a sputtering method, an ion plating method or the like, or by coating a metallic coating agent in which metal flakes are dispersed. The method etc. are mentioned. Furthermore, it is preferably used also for a metal-less metal tone film that expresses a metal tone by interference reflection in a configuration in which two types of polymers having different refractive indexes are alternately laminated. Specific examples include a reflective film (metal film) described in JP-A-2007-003764. Further, examples of the pearl tone film include a method in which a pearl pigment is kneaded and mixed in the film, or a coating method in which a pearl pigment is dispersed is coated to develop a pearl tone.

  As described above, the surface protective polyester film for molding according to the present invention is preferably used by being laminated on the surface of the decorative sheet for molding or the decorative film for molding. The method for laminating the decorative sheet for molding and the decorative film for molding on the surface is not particularly limited, but an adhesive layer is placed on the surface-protecting polyester film for molding process of the present invention, and the decorative sheet for molding is interposed via the adhesive layer. And it can be laminated only by heating and pressurizing without using a method of laminating on the surface of the decorative film for molding or an adhesive layer. The adhesive layer is not particularly limited, but acrylic, copolyester, modified thermoplastic elastomers and the like are preferably used. In the case where an adhesive layer is provided, the peelability after molding may be lowered, so that it is preferable to use a slightly adhesive layer. The method for installing the adhesive layer is not particularly limited, and examples thereof include a roller coating method, a brush coating method, a spray coating method, a dip coating method, and a method using a die coater, a bar coater, and a knife coater. Next, the conditions of the drying step to be performed may vary depending on the film thickness, the type of the selected solvent, etc., but can be 20 to 60 seconds at 80 to 150 ° C., preferably 100 to 130 ° C. 30 to 50 seconds. Thereby, the contact bonding layer which has a thickness of 1-50 micrometers can be provided on a base material layer.

  Furthermore, as a method of laminating and using the decorative sheet for molding, the present invention is used as a carrier film, and the thermoplastic resin sheet (base material) is “clear layer” or “decorative layer / clear layer”. Is used as a protective film during molding of the decorative sheet for molding (the carrier film becomes a protective film as it is). Since the economic effect by simplification of a process becomes large, it is very preferable.

  A method for producing a molding laminate in which the molding protective surface film of the present invention is laminated on the molding decorative sheet with the above-described configuration will be specifically described. The present invention is not limited to this.

  A polyvinylidene fluoride dispersion liquid dispersed in polymethyl methacrylate is die-coated on a polyethylene terephthalate carrier film by die coating, and a clear layer is laminated and dried. Furthermore, the dispersion of the polyvinylidene fluoride dispersed in polymethyl methacrylate is laminated with a dispersion of the colorant by a die coating method and dried, so that the carrier film / clear layer / decorative layer A construct is made. On the decorative layer of the structure, an acrylic polymer is laminated as a primer layer, and a urethane resin / epoxy crosslinking agent is laminated as an adhesive layer. The carrier film / clear layer / decorative layer / primer layer / adhesive layer structure obtained by such a method is bonded to a TPO sheet having a corona-treated surface via an adhesive layer. Thereafter, the carrier film is peeled off to obtain a decorative sheet for molding having a configuration of TPO sheet / adhesive layer / decorative layer / clear layer. Furthermore, the molding laminate in which the molding protective surface protective film of the present invention is laminated on the molding decorative sheet by thermocompression bonding, and the molding decorative sheet is laminated on the molding decorative sheet. Produced.

  In addition, a method for producing a molding laminate in which the molding protective surface protective polyester film of the present invention is laminated on the molding decorative film is also specifically described. The present invention is not limited to this.

  A modified thermoplastic elastomer is laminated as a slightly adhesive layer on the protective polyester film for molding process of the present invention, and a reflective film (metal-like film) described in JP-A-2007-003764 is applied on the laminator while applying pressure thereto. By laminating a film, a molding laminate having a configuration of a molding decorative film (metal-tone film) / slight adhesion layer / molding surface protective polyester film is produced.

  Next, although the forming method of this forming laminate will be specifically described, the forming method is not limited thereto.

  The molding laminate is heated using a far-infrared heater at 150 to 400 ° C. so that the surface temperature becomes 30 to 200 ° C., the mold is pushed up, and the mold is evacuated to form a desired shape. . In the case of molding with a strict magnification, deeper molding is possible by applying pressure air to the sheet and molding. The molding laminate thus molded is trimmed to obtain a molding in which the surface protective polyester film for molding processing of the present invention is laminated as a protective film. The molded body may be used as it is. However, in order to impart strength as a molded product, TPO, polycarbonate, ABS resin, or the like may be injected into a depressed portion by pressing a mold. In this manner, the molded member is completed by peeling the surface-protecting polyester film for molding from the molded body.

  The molded member thus obtained has a high glossiness, has almost no defects such as scratches, distortions and undulations on the surface, and exhibits a very good appearance. It is preferably used as a part for electric appliances and the like.

  As above-mentioned, the molded member obtained can make the absolute value of the difference of the glossiness with the decorative sheet for shaping | molding before shaping | molding, and the decorative film for shaping | molding less than ten. If the absolute value of the difference in glossiness is less than 10, it is preferable that no significant difference is observed in the gloss determination visually before and after molding, and the glossiness designed before molding can be maintained. More preferably, the absolute value of the difference in glossiness from before molding is less than 5, and most preferably less than 3.

  In addition, the surface protective polyester film for molding process of the present invention may control the surface free energy of the film surface in order to impart releasability after molding. The surface free energy on the film surface is preferably 15 to 47 mN / m because the peelability after molding becomes good. When the surface free energy is less than 15 mN /, it is not preferable because the adhesive force becomes insufficient when laminated on the decorative sheet for molding and the decorative film for molding, and may not follow during molding. Moreover, when surface free energy becomes larger than 47 mN / m on the film surface, since the peelability after shaping | molding may fall, it is unpreferable. As a method for setting the surface free energy on the film surface within the above range, a release layer containing a water repellent compound such as a silicone compound, a fluorine compound, or a wax compound is laminated on the film surface, or these compounds are applied to a polyester resin. The method of kneading is mentioned.

  Further, the surface-protecting polyester film for molding process of the present invention may be recovered after being peeled from the molded body and used again. Furthermore, melting the recovered film, pelletizing it again, and using it as a raw material for film formation as a recovered raw material is very economical and environmentally superior.

 The surface-protecting polyester film for molding according to the present invention has excellent molding processability, and can easily form a molded part that follows the mold in thermoforming such as vacuum and pressure forming. For this reason, since the appearance of a molded part becomes beautiful by using it as a decorative sheet for molding or a surface protective film at the time of molding a decorative film for molding, the finished molded body is a building material, an automobile part. It is preferably used as a component for mobile phones and electric products.

(1) Melting point The melting point was measured using a differential scanning calorimeter (Seiko Denshi Kogyo RDC220). When 5 mg of film is used as a sample and there are multiple endothermic peaks with the endothermic peak temperature at 25 ° C. up to 300 ° C. at 20 ° C./min, the peak temperature of the endothermic peak on the highest temperature side is the melting point. It was.

(2) Intrinsic viscosity of polyester The intrinsic viscosity of the polyester resin and the film was measured at 25 ° C. using an Ostwald viscometer after dissolving the polyester in orthochlorophenol.

(3) Polyester composition Polyester resin and film can be dissolved in hexafluoroisopropanol (HFIP), and the content of each monomer residue and by-product diethylene glycol can be quantified using ¹ H-NMR and ¹³ C-NMR. . In the case of a laminated film, the components constituting each layer can be collected and evaluated by scraping off each layer of the film according to the laminated thickness. In addition, about the film of this invention, the composition was computed by calculation from the mixing ratio at the time of film manufacture.

(4) 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 the longitudinal direction and the width direction to obtain a sample. Using a tensile tester (Orientec Tensilon UCT-100), the tensile test was performed in the longitudinal direction and the width direction of the film at an initial tensile chuck distance of 50 mm and a tensile speed of 300 mm / min. For the measurement, a film sample was set in a constant temperature layer set to 150 ° C. or 200 ° 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 distance between chucks is 100 mm), and divide by the cross-sectional area (film thickness x 10 mm) of the sample before the test. F100 value). In addition, the measurement was performed 5 times for each sample and each direction, and the average value was evaluated.

(5) Elongation In the same manner as in (3), a tensile test was performed in the longitudinal direction and the width direction of the film, and the elongation when the film was broken was defined as the respective elongation. In addition, the measurement was performed 5 times for each sample and each direction, and the average value was evaluated.

(6) Formability
(i) Molding decorative sheet A polyvinylidene fluoride dispersion dispersed in 10% by mass in polymethyl methacrylate is die-coated on a 50 μm polyethylene terephthalate carrier film by die coating, a clear layer is laminated, and 200 ° C. for 10 seconds. Dried. Further, on the clear layer, an acrylic polymer (68070 manufactured by Dupon Co.) as a primer layer was dispersed in 30% by mass in toluene, coated with a gravure coater, and further an adhesive AD503 manufactured by Toyo Morton Co., Ltd. as an adhesive layer. Then, an adhesive mixed with 20: 1: 20 of the curing agent CAT10 and ethyl acetate was applied. After the carrier obtained by such a method is subjected to corona treatment on the surface of the TPO sheet, the carrier is adhered via an adhesive layer, and the carrier film is peeled off to form a TPO sheet / adhesive layer / clear layer. A decorative sheet for molding was obtained. Furthermore, the decorative sheet for molding was laminated by subjecting the surface-protecting polyester film for molding processing of the present invention to thermocompression bonding (150 ° C., 0.3 MPa, 10 m / min) to prepare a molding laminate. The molding laminate was heated using a far-infrared heater at 400 ° C. so that the surface temperature was 150 ° C., and vacuum molding was performed along a mold (bottom diameter 50 mm) heated to 50 ° C. It was. The state of being molded along the mold was evaluated according to the following criteria using the molding degree (drawing ratio: molding height / bottom diameter).
A: Molding was possible with a drawing ratio of 0.5 or more.
○: Molding was possible with a drawing ratio of 0.5 to 0.3.
Δ: Molding was possible with a drawing ratio of 0.3.
×: Low followability and could not be molded into a shape with a drawing ratio of 0.3. XX: Breaking occurred and could not be formed with a drawing ratio of 0.3.

(ii) Decorative film for molding An adhesive layer was placed on the surface-protecting polyester film for molding processing of the present invention. The adhesive layer was prepared by mixing Tuftec M1911 (manufactured by Asahi Kasei), Coronate HL (manufactured by Nippon Polyurethane Industry), Elegan 264WAX (manufactured by Nippon Oil & Fats), and toluene in a mass ratio of 15: 1.4: 0.1: 83.5. In the surface protective polyester film for molding processing of the present invention, it was installed so as to have a thickness of 1.5 μm. On top of that, by applying pressure (room temperature, 0.1 MPa, 10 m / min) using a laminator, 201 layers of polyethylene terephthalate and 20 mol of cyclohexanedimethanol-copolymerized polyethylene terephthalate were alternately laminated (a metallic film). By laminating the film, a laminate for molding having a configuration of decorative film for molding (metallic film) / adhesive layer / surface protective polyester film for molding was produced. The molding laminate is heated using a far-infrared heater at 400 ° C. so that the surface temperature becomes 200 ° C., and is formed by vacuum / compression molding along a mold (bottom diameter 50 mm) heated to 50 ° C. Pressure: 1 MPa). The state of being molded along the mold was evaluated according to the following criteria using the molding degree (drawing ratio: molding height / bottom diameter).
A: Molding was possible with a drawing ratio of 0.3 or more.
○: Molding was possible at a draw ratio of 0.2 to 0.3.
Δ: Molding was possible with a drawing ratio of 0.2.
×: Low followability and could not be molded into a shape with a drawing ratio of 0.3. XX: Breaking occurred and could not be formed with a drawing ratio of 0.3.

(7) Easy peelability
(i) Molding decorative sheet From the molded sheet molded by the method of (6), the protective polyester film for molding according to the present invention is peeled at 25 ° C. and 65% RH atmosphere at a peeling angle of 90 degrees, Evaluation based on the criteria.
(Double-circle): It peeled without resistance at all.
○: Peeled almost without resistance.
Δ: Slight resistance was felt, but peeling was possible without any problem.
X: A strong resistance was felt and it was difficult to peel off.

(ii) The peelability was evaluated in the same manner as in the decorative film for molding (7) (i) (the evaluation criteria were also the same).

(8) Glossiness
(i) Decorative sheet for molding The method defined in JIS-Z-8741 (1997) for the surface of the molded product after peeling the surface-protecting polyester film for molding processing of the present invention by the method of (7). Thus, the 60 ° specular gloss was measured using a digital variable angle gloss meter UGV-5D manufactured by Suga Test Instruments. The measurement was performed at n = 5, and the average value excluding the maximum value and the minimum value was defined as the glossiness, and evaluation was performed according to the following criteria.
A: The absolute value of the difference in glossiness between the decorative sheets before and after molding was less than 3.
(Circle): The absolute value of the difference of the glossiness of the decorating sheet before and behind shaping | molding was 3-5.
(Triangle | delta): The absolute value of the glossiness difference of the decorative sheet before and behind shaping | molding was 5-10.
X: The absolute value of the difference in glossiness between the decorative sheets before and after molding was greater than 10.

(ii) Glossiness was evaluated in the same manner as the decorative decorative film (8) (i) (the evaluation criteria were also the same).

(Manufacture of polyester)
The polyester resin used for film formation was prepared as follows.

(PET)
To a mixture of 100 parts by weight of dimethyl terephthalate and 70 parts by weight of ethylene glycol, 0.09 parts by weight of magnesium acetate and 0.03 parts by weight of antimony trioxide are added, the temperature is gradually raised, and finally Conducted transesterification 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. Polyethylene in which the reaction system is gradually depressurized while being heated in a polymerization kettle and subjected to a polycondensation reaction at 290 ° C. under a reduced pressure of 1 hPa, and an intrinsic viscosity of 0.65 and 2 mol% of diethylene glycol as a by-product are copolymerized. A terephthalate resin was obtained.

(Particle master) * Indicated in the table as particle M When producing the polyester A, after the transesterification reaction, an ethylene glycol slurry of agglomerated silica particles having an average particle size of 2.4 μm is added, and then a polycondensation reaction is carried out to produce a polymer. A particle master having a particle concentration of 2% by mass was produced.

(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. Then, 0.054 parts by mass of monohydroxybutyltin oxide was added to carry out an esterification reaction. Next, 0.066 parts by mass of tetra-n-butyl orthotitanate was added and a polycondensation reaction was performed under reduced pressure to prepare a polybutylene terephthalate resin having an intrinsic viscosity of 0.88. Thereafter, crystallization was 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 a polybutylene terephthalate resin having an intrinsic viscosity of 1.22.

(PTT)
Using 100 parts by weight of dimethyl terephthalate and 80 parts by weight of 1,3-propanediol as a catalyst in a nitrogen atmosphere, the temperature was gradually raised from 140 ° C. to 230 ° C., and the ester exchange reaction was carried out while distilling methanol. went. Further, a polycondensation reaction was carried out for 3 hours under a constant temperature of 250 ° C. to obtain a polytrimethylene terephthalate resin having an intrinsic viscosity [η] of 0.86.

(PET-G)
To a mixture of 100 parts by weight of dimethyl terephthalate, 60 parts by weight of ethylene glycol, and 20 parts by weight of 1,4-cyclohexanedimethanol, 0.04 parts by weight of manganese acetate is added, and the temperature is gradually raised. Transesterification was carried out while distilling methanol at 0 ° C. Next, 0.045 parts by mass of 85% phosphoric acid aqueous solution and 0.01 parts by mass of germanium dioxide were added, and the temperature was gradually raised and reduced. Finally, the temperature was raised to 275 ° C. and 1 hPa, and the intrinsic viscosity was reduced. The polycondensation reaction was carried out until 0.67, and then a strand was discharged, cooled, and cut to obtain a polyethylene terephthalate resin copolymerized with 8 mol% of 1,4-cyclohexanedimethanol. The polymer was cut into cubes having a diameter of 3 mm, and solid phase polymerization was performed using a rotary vacuum polymerization apparatus under a reduced pressure of 1 hPa at 225 ° C. until the intrinsic viscosity was 0.8.

(PET-I)
To a mixture of 82.5 parts by weight of dimethyl terephthalate, 5 parts by weight of dimethyl isophthalate, and 70 parts by weight of ethylene glycol, 0.09 parts by weight of magnesium acetate and 0.03 parts by weight of antimony trioxide are added, The temperature was gradually raised, and finally transesterification was carried out while distilling methanol at 220 ° C. Subsequently, 0.020 parts 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 is gradually depressurized while being heated in the polymerization kettle, and the polycondensation reaction is performed at 287 ° C. under a reduced pressure of 1 hPa, and the intrinsic viscosity is 0.7 and by-product diethylene glycol is copolymerized by 2 mol%. An acid 5 mol% copolymerized polyethylene terephthalate resin was obtained.

(Example 1)
PET, PBT, PTT, and particle master were mixed at a mass ratio of 68: 15: 15: 2, dried at 180 ° C. for 4 hours in a vacuum dryer, and after sufficiently removing moisture, supplied to a single screw extruder. After melting at ℃, removing foreign matter and leveling the amount of extrusion, it was discharged from a T-die onto a cooling drum whose temperature was controlled at 25 ℃. 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.

  Then, before stretching in the longitudinal direction, the film temperature is raised with a heating roll, the preheating temperature is 110 ° C., the stretching temperature is 105 ° C., the stretching is 3.0 times in the longitudinal direction, and the temperature is immediately controlled to 40 ° C. Cooled with a roll. Next, the film was stretched 3.0 times in the width direction at a preheating temperature of 95 ° C. and a stretching temperature of 120 ° C. with a tenter-type transverse stretching machine, and while being relaxed by 4% in the width direction in the tenter, the temperature was maintained at 240 ° C. for 5 seconds. Heat treatment was performed to obtain a biaxially oriented polyester film having a film thickness of 38 μm.

  Then, it laminated | stacked on the decorative sheet for shaping | molding and the decorative film for shaping | molding using the method described in (6) moldability, and thermoformability was evaluated. Since the film has a low F100 value at 150 ° C. and 200 ° C. and a high elongation, it has excellent moldability and excellent peelability. As a surface protective polyester film, it showed very good characteristics.

(Example 2)
A biaxially oriented polyester film having a film thickness of 25 μm was obtained in the same manner as in Example 1 except that PET, PBT, PTT and particle master were mixed at a mass ratio of 78: 15: 5: 2. Compared with Example 1, the film had a slightly lower elongation at 150 ° C., so the moldability was slightly reduced, but it showed excellent properties as a surface protective film for molding.

(Example 3)
PET and PET-I were mixed at a mass ratio of 97: 3, and an unstretched film having a film thickness of 50 μm was obtained in the same manner as in Example 1. Although the film was very excellent in moldability, it was an unstretched film, so it was slightly inferior in heat resistance, whitening occurred during molding, easy peelability, and glossiness slightly deteriorated as a result. As a surface protection film for molding, it was at a level with no problem.

Example 4
A biaxially oriented polyester film having a film thickness of 38 μm was obtained in the same manner as in Example 1 except that PET, PBT, and particle master were mixed at a mass ratio of 68: 30: 2. The film had a slightly higher F100 value in the width direction than Example 1, so that the moldability was slightly lowered, and the easy peelability was slightly inferior in the test of the decorative sheet for molding. Although affected, it showed excellent properties as a surface protective film for molding.

(Example 5)
A biaxially oriented polyester film having a film thickness of 25 μm was obtained in the same manner as in Example 1 except that PET-I and particle master were mixed at a mass ratio of 97: 3. The film had a slightly higher F100 value at 150 ° C. and 200 ° C. compared to Example 1, so that the moldability was slightly lowered, and the film had a low melting point. And transfer to the clear layer, resulting in a slightly low gloss, but it was at a level that was not a problem as a surface protective film for molding.

(Example 6)
A three-layer film of A / B / A was obtained. As polyester A constituting the A layer, PET, PBT, PET-G and particle master were mixed at a mass ratio of 52: 15: 30: 3. As polyester B constituting the B layer, PET, PBT, and PETG were mixed and used at a mass ratio of 55:25:20.

  Each mixed polyester resin was individually dried in a vacuum dryer at 180 ° C. for 4 hours, and after sufficiently removing moisture, supplied to separate single screw extruders, melted at 280 ° C., and filtered through separate paths. After removing the foreign matter and leveling the amount of extrusion through the gear pump, A layer / B layer / A layer (see the table for lamination thickness ratio) in the feed block installed on the top of the T die After the lamination, 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 the cooling drum to obtain an unstretched film.

  Next, before stretching in the longitudinal direction, the film temperature is raised with a heated roll, the preheating temperature is 110 ° C., the stretching temperature is stretched in the longitudinal direction at 105 ° C., and immediately cooled with a metal roll whose temperature is controlled at 40 ° C. did. Next, the film was stretched 3.1 times in the width direction at a preheating temperature of 95 ° C. and a stretching temperature of 120 ° C. with a tenter-type transverse stretching machine, and while being relaxed by 4% in the width direction in the tenter, the temperature was maintained at 240 ° C. for 5 seconds. Heat treatment was performed to obtain a biaxially oriented polyester film having a film thickness of 19 μm. The film had a high gloss after molding, and exhibited very excellent characteristics as a surface protective polyester film for molding.

(Example 7)
A biaxially oriented polyester film having a film thickness of 38 μm, as in Example 1, except that PET, PBT and particle master were mixed at a mass ratio of 88: 10: 2 and the draw ratio in the longitudinal direction was 3.2 times. Got. Compared to Example 1, the film had higher F100 values at 150 ° C. and 200 ° C. and slightly lower elongation, so that the moldability was lowered, but there was no problem as a surface protective film for molding processing. It was a level.

(Example 8)
Using 100% by mass of PET, an unstretched film having a film thickness of 50 μm was obtained in the same manner as in Example 3. The film was very excellent in formability, but because it is an unstretched film, it was slightly inferior in heat resistance, partly whitened during molding, resulting in inferior easy peelability, and slightly glossiness However, it was a level with no problem as a surface protective film for molding.

Example 9
Biaxial orientation with a film thickness of 50 μm in the same manner as in Example 1 except that PET, PET-G and particle master were mixed at a mass ratio of 58: 40: 2 and the draw ratio in the longitudinal direction was changed to 3.3 times. A polyester film was obtained. Compared with Example 1, the film had a high F100 value at 150 ° C. and 200 ° C., so that the moldability was slightly lowered, but exhibited excellent properties as a surface protective film for molding.

(Comparative Example 1)
A film was prepared in the same manner as in Example 1 except that PET and particle master were mixed at a mass ratio of 98: 2, and the longitudinal preheating temperature was 90 ° C., and the stretching temperature was 95 ° C. and the stretching was 3.3 times in the longitudinal direction. A biaxially oriented polyester film having a thickness of 25 μm was obtained. The film has a high F100 value at 150 ° C. and 200 ° C. compared to the examples, and the elongation is low, so the moldability is inferior, and the film is broken, so that the surface is scratched, and the effect And the glossiness was low, and the film had poor properties as a surface protective film for molding.

(Comparative Example 2)
A biaxially oriented polyester film having a film thickness of 38 μm was obtained in the same manner as in Comparative Example 1 except that PET, PBT and particle master were mixed at a mass ratio of 93: 5: 2. Since this film had a high F100 value at 150 ° C. and 200 ° C. compared to the examples, it was inferior in molding followability and inferior in properties as a surface protective film for molding.

(Comparative Example 3)
As polyester A constituting the A layer, PET, PBT and particle master were mixed at a mass ratio of 47: 50: 3 and used. As polyester B constituting the B layer, PET and PET-G were mixed and used at a mass ratio of 90:10. Except that the lamination thickness ratio is as shown in the table, the preheating temperature in the longitudinal direction is 95 ° C., and the stretching temperature is 100 ° C., the same as in Example 6,
A biaxially oriented polyester film having a film thickness of 38 μm was obtained. Compared with the examples, the film has a high F100 value at 150 ° C. and 200 ° C. and a slightly large amount of PBT on the surface layer. The film was inferior in properties as a surface protective film for molding.

(Comparative Example 4)
A biaxially oriented polyester film having a film thickness of 38 μm was obtained in the same manner as in Example 1 except that PET and the particle master were mixed at a mass ratio of 97: 3. The film had a high F100 value at 150 ° C. and a low elongation compared to the Examples, and the film was broken and scratched on the surface. Thus, the film was inferior in properties as a surface protective film for molding.

(Comparative Example 5)
An unstretched film having a film thickness of 50 μm was obtained in the same manner as in Example 3 except that PET and PBT were mixed at a mass ratio of 95: 5. Since the film was an unstretched film and the F100 value at 200 ° C. was very low, the film lost heat during the preheating process at the time of molding, resulting in waviness and a molding test could not be performed. It was a film that could not be used as a surface protective film for molding.

  The present invention relates to a polyester film, and more particularly to a surface protective film when molding a decorative sheet for molding or a decorative film for molding. Low stress, high elongation, and excellent moldability, so it has excellent molding followability after being laminated on the surface of a decorative sheet for molding or decorative film for molding. Degradation can be prevented.

Claims (10)

A surface-protecting polyester film for molding process having a stress at 100% elongation (F100 value) of 1 to 70 MPa and an elongation of 200 to 800% in the film longitudinal direction and the width direction at 150 ° C and 200 ° C. The surface-protecting polyester film for molding according to claim 1, which is a biaxially oriented film. Polyethylene terephthalate resin A and polybutylene terephthalate resin and / or polyester resin B selected from the group consisting of polytrimethylene terephthalate resin are 100% by mass of the entire film, and resin A is 10 to 90% by mass. %, The surface-protective polyester film for molding processing according to claim 1, wherein the polyester-based resin composition is mixed at 90 to 10% by mass. The resin B includes a polybutylene terephthalate resin b1 and a polytrimethylene terephthalate resin b2, and the total amount of the resin b1 and the resin b2 is 100% by mass. The resin b1 is 10 to 90% by mass, and the resin b2 is 90%. The surface-protecting polyester film for molding according to any one of claims 1 to 3, which is mixed at 10 to 10% by mass. The surface-protecting polyester film for molding according to any one of claims 1 to 4, which is used by being laminated on the surface of the molding decorative sheet. The surface-protecting polyester film for molding according to any one of claims 1 to 4, which is used by being laminated on the surface of a decorative film for molding. The molding laminated body which laminated | stacked the surface protection polyester film for shaping | molding processing in any one of Claims 1-4 on the surface of the decoration sheet for shaping | molding. The laminated body for shaping | molding which laminated | stacked the surface protection polyester film for shaping | molding processing in any one of Claims 1-4 on the surface of the decorative film for shaping | molding. A molding method for a molded member, wherein the molding laminate according to claim 7 or 8 is pre-molded and trimmed, then a resin is injected, and the surface-protecting polyester film for molding processing is peeled off. A molded member obtained by peeling off the molding surface-protecting polyester film after molding the molding laminate according to claim 7, wherein the molding decorative sheet or molding additive before molding is formed. The molded member whose absolute value of the difference in glossiness of the surface with the decorative film is less than 10.