JP2010274646A - Laminated polyester film for molding - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a laminated polyester film for molding excellent in adhesion and suitable for decorative properties even under a wet heat environment. <P>SOLUTION: The laminated polyester film for molding includes a laminated polyester film having an easily adhesive layer at least on one side of a base material film including a copolyester, or a copolyester and a homopolyester. In the laminated polyester film for molding, the easily adhesive layer includes a polyester graft copolymer and a polycarbonate polyurethane, the polyester graft copolymer is grafted with a polymerizable unsaturated monomer containing acid anhydride having at least one kind of double bonds on a hydrophobic copolyester resin, and also a glass transition point (Tig) of the easily adhesive layer is 30°C to 55°C. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a molding polyester film. In particular, the present invention relates to a molding polyester film excellent in decorating properties and processability.

  Conventionally, as a sheet | seat for shaping | molding, a polyvinyl chloride film is typical and has been preferably used at points, such as workability. However, there are problems in terms of environmental suitability, such as generation of toxic gas when the film is burned and bleeding out of the plasticizer.

  Thus, unstretched sheets made of polyester, polycarbonate, or acrylic resin have been used in a wide range of fields as materials having excellent environmental suitability. For example, as in Patent Document 1, a laminated polyester film for molding having a characteristic excellent in moldability has been proposed.

  On the other hand, various proposals have heretofore been made as methods for improving the adhesion of a polyester film. For example, Patent Document 1 discusses a method using a copolyester, and Patent Document 2 uses a copolyester and a water-soluble polyurethane resin as an easy adhesion layer. Further, Patent Document 3 proposes an optically easy-adhesive polyester film having an easy-adhesive layer containing a polyester resin having a glass transition point of 40 to 100 ° C. and a crosslinking agent in order to prevent scratches.

JP 2008-30475 A JP-A-2005-290354 JP 2003-49011 A

  In particular, when the molding film is used as a decorative molding member, the molding film is molded after the easy-adhesion layer provided on the film surface is printed. Such a molded body is used outdoors or indoors as an interior material or exterior material for home appliances, mobile phones, automobiles, or a member for building materials. Under such circumstances, the molded body is expected to be exposed to high temperature and humidity for a long time. Therefore, after molding, it is required to maintain good adhesiveness with the printed layer even in a humid heat environment.

  In general, in order to improve the heat and moisture resistance of the coating film itself, a method of increasing the degree of crosslinking of the coating film and forming an easy-adhesion layer having a high glass transition point is performed. However, the easy-adhesion layer having such a high degree of cross-linking has a hard coating film and the molding followability is lowered, so when used as a molding film, the adhesiveness in a wet and heat environment may decrease as a result. is there. For example, when a biaxially oriented polyester film is formed using a vacuum forming method, the film may locally extend to 100% or more near the corner of the mold. Thus, although a base material has high moldability, in the coating film with a high bridge | crosslinking degree, it cannot follow a deformation | transformation of a base material, and peeling and a crack of a printing layer will arise.

  On the other hand, when an easy-adhesion layer having a low glass transition point is laminated, moldability is improved, and initial adhesion is improved even after molding. However, since the wet heat resistance of the coating film tends to be lowered, the adhesiveness with the printing layer in a wet heat environment is lowered. For this reason, it has been extremely difficult to obtain a laminated polyester film for molding having flexibility that can withstand the molding process and having heat and moisture resistance.

  An object of the present invention is to solve the above problems. That is, it is an object to provide a laminated polyester film for molding suitable for decorating that is excellent in adhesiveness even in a humid heat environment by highly balancing the trade-off characteristics of flexibility and wet heat resistance of an easy adhesion layer. To do.

The laminated polyester film for molding according to the present invention, which can solve the above problems, has the following configuration.
A first invention is a laminated polyester film having an easy-adhesion layer on at least one side of a base film made of copolymerized polyester or copolymer polyester and homopolyester, wherein the easy-adhesion layer is a polyester-based graft copolymer And a polyester-based graft copolymer in which a polymerizable unsaturated monomer containing an acid anhydride having at least one double bond is grafted to a hydrophobic copolymerized polyester resin. And a glass transition point (Tig) of the easy-adhesion layer is 30 ° C. to 55 ° C., and is a laminated polyester film for molding.
In the second invention, the blending ratio of the polyester-based graft copolymer and the polycarbonate-based polyurethane in the easy-adhesion layer is polyester-based graft copolymer / polycarbonate-based polyurethane (mass ratio) = 80/20 to 30/70. And it is the said laminated polyester film for shaping | molding containing 5-40 mass parts crosslinking agent with respect to 100 mass parts of total amounts of a polyester-type graft copolymer and a polycarbonate-type polyurethane.
A third invention is the laminated polyester film for molding, wherein the crosslinking agent is a blocked isocyanate crosslinking agent.
4th invention is the said laminated isocyanate film for shaping | molding whose reproduction | regeneration isocyanate group content of the said block isocyanate type crosslinking agent is 3-15 mass%.
5th invention is the laminated polyester film for shaping | molding characterized by the haze being 1.0% or less.
6th invention is the said laminated polyester film for shaping | molding characterized by the thickness of the said easily bonding layer being 0.01-0.10 micrometer.
7th invention is the molded object which laminated | stacked the printing layer on the easily bonding layer of the said lamination | stacking polyester film for a shaping | molding.
The eighth invention is a molded article in which a printing layer, an adhesive layer, and an acrylic resin sheet are sequentially laminated on the easy-adhesion layer of the molding laminated polyester film, and a metal thin film layer is provided on the opposite surface.

  In the laminated polyester film for molding of the present invention, an easy adhesion layer having a specific resin configuration and a specific glass transition point is laminated. Therefore, it has good molding followability and good adhesion to the printed layer even in a moist heat resistant environment. Therefore, it can be suitably used as a decorative molding member such as a building material member, an interior or exterior decoration material for automobiles, a home appliance membrane switch, and a mobile phone base material.

(Easily adhesive layer)
The easy-adhesion layer of the present invention will be described in detail.
The present inventor has intensively studied how to satisfy the contradictory properties of flexibility and moisture-heat resistance of the easily adhesive layer. As a result, it has been considered to control the glass transition point as an index for prescribing the flexibility of the easy-adhesion layer, but the resin composition constituting the easy-adhesion layer even if it has the same glass transition temperature The inventors have focused on the fact that the heat-and-moisture resistance changes depending on the structure of the present invention, and have reached the present invention. That is, the easy-adhesion layer of the present invention comprises a polyester-based graft copolymer described later and a polycarbonate-based polyurethane, and the glass transition point (Tig) of the easy-adhesion layer is 30 ° C. to 55 ° C.

  The minimum of the glass transition point (Tig) of the easily bonding layer of this invention is 30 degreeC, Preferably it is 35 degreeC, and an upper limit is 55 degreeC, Preferably it is 50 degreeC. If the glass transition point (Tig) of the easy-adhesion layer is less than 35 ° C., sufficient moisture and heat resistance may not be obtained, and the blocking resistance also decreases. If the glass transition point (Tig) of the easy-adhesion layer exceeds 55 ° C., the flexibility of the easy-adhesion layer tends to decrease, and the moisture and heat resistance after molding may decrease. In order to achieve both the heat and moisture resistance and the moldability, it is desirable to set the glass transition point (Tig) of the easy-adhesion layer in such a very narrow specific range. Even if the polyester component and the polyurethane component each have a glass transition point (Tig) within the above range, when an easy-adhesion layer having a crosslinked structure is laminated together with a crosslinking agent in the film forming step, the glass transition point (Tig) May exceed 38 ° C., and sufficient moldability and adhesion in a heat-and-humidity environment cannot be obtained. In order to maintain the glass transition point (Tig) even if it has a crosslinked structure, an appropriate amount of crosslinking agent, an amount of polyurethane and an amount of polyester-based graft copolymer, and a hydrophobic copolymerizable polyester This can be achieved by setting the mass ratio of the resin and the polymerizable unsaturated monomer to a range described later.

  The glass transition point referred to in the present invention is JIS-K7121 in a state where it is laminated as an easy-adhesion layer in a film forming process, that is, in a state where a polyester-based graft copolymer and a polycarbonate-based polyurethane are crosslinked with a crosslinking agent. The extrapolated glass transition start temperature (Tig) measured by a method based on the above.

(Polyester graft copolymer)
In the present invention, the polyester-based graft copolymer is contained in the easy adhesion layer as described above. The polyester-based graft copolymer is necessary for imparting adhesion to the base film and the printing layer. The polyester-based graft copolymer can form a highly self-crosslinking structure and thus has a good effect on moisture and heat resistance. Furthermore, the polyester-based graft copolymer has an adhesive property between the base film and the easy-adhesion layer. Can be improved. If the polyester-based graft copolymer is not included, the micro-adhesive layer is likely to peel off, resulting in not only the printing layer being chipped, but also a decrease in adhesiveness in a moisture and heat resistant environment. Come on. The polyester-based graft copolymer used in the present invention is a polymerizable unsaturated monomer containing an acid anhydride having at least one double bond in a hydrophobic copolymerized polyester resin from the viewpoint of heat and moisture resistance of an easy-adhesion layer. Is used which is grafted. Hereinafter, the polyester-based graft copolymer used in the present invention will be described.

  The polyester-based graft copolymer contained in the easy-adhesion layer is blended in the range of 5 to 90% by mass with respect to the entire solid content of the easy-adhesion layer in order to impart adhesion between the base film and the easy-adhesion layer. Preferably, it is 30 to 80% by mass.

  In the present invention, “grafting” is to introduce a branched polymer composed of a polymer different from the main chain into the main chain of the main polymer. In the present invention, a polymerizable unsaturated monomer containing an acid anhydride having at least one double bond using a radical initiator in a state where a hydrophobic copolymerizable polyester resin is dissolved in an organic solvent It is preferable to carry out graft polymerization by reacting. The reaction product after completion of the grafting reaction is a hydrophobic copolymerizable polyester resin that has not undergone grafting, in addition to the graft copolymer of the desired hydrophobic copolymerizable polyester and polymerizable unsaturated monomer. And a polymer of the above unsaturated monomer that has not been grafted to the hydrophobic copolymerizable polyester. The polyester-based graft copolymer in the present invention includes not only the above-described polyester-based graft copolymer but also an unreacted hydrophobic copolymerizable polyester, a polymer of an unsaturated monomer that has not been grafted, and the like. Also referred to as reaction mixture.

In the present invention, the acid value of the polyester-based graft copolymer obtained by graft polymerization of a polymerizable unsaturated monomer to a hydrophobic copolymerizable polyester resin is preferably 600 eq / 10 ⁶ g or more. More preferably, it is 1200 eq / 10 ⁶ g or more. When the acid value of the graft copolymer is less than 600 eq / 10 ⁶ g, it cannot be said that the adhesion to the substrate film is sufficient.

  The mass ratio of the hydrophobic copolymerizable polyester resin and the polymerizable unsaturated monomer to obtain a desirable graft copolymer suitable for the purpose of the present invention is polyester / polymerizable unsaturated monomer = The range of 40/60 to 95/5 is desirable, more desirably 55/45 to 93/7, and most desirably 60/40 to 90/10. When the mass ratio of the hydrophobic copolymerizable polyester resin is less than 40% by mass, the glass transition point (Tig) of the obtained easy-adhesion layer is increased, the followability at the time of molding is lowered, and in a moisture and heat resistant environment. In some cases, the adhesiveness of the resin may deteriorate. On the other hand, when the mass ratio of the hydrophobic copolymerizable polyester resin is larger than 95% by mass, blocking tends to occur.

  The graft copolymer is in the form of an organic solvent solution or dispersion, or an aqueous solvent solution or dispersion. In particular, a dispersion of an aqueous solvent, that is, a form of a water-dispersed resin is preferable from the viewpoint of working environment and coating properties. Such a water-dispersed resin is usually obtained by graft polymerization of at least one hydrophilic polymerizable unsaturated monomer onto the hydrophobic copolymerizable polyester resin in an organic solvent, followed by water addition and organic It can be obtained by distilling off the solvent.

  The glass transition point (Tig) of the graft copolymer is 70 ° C. or lower, preferably 50 ° C. or lower. By using a graft copolymer having a glass transition point (Tig) of 70 ° C. or less for the graft copolymer-containing layer, it has good followability at the time of molding after the printing layer is laminated, and excellent printing even in a heat and humidity resistant environment. Easy adhesion of layer.

(Hydrophobic copolymerizable polyester resin)
In the present invention, the hydrophobic copolymerizable polyester resin is essentially water-insoluble which does not inherently disperse or dissolve in water. When a polyester resin that is dispersed or dissolved in water is used for graft polymerization, the adhesiveness in a heat-and-moisture resistant environment, which is the object of the present invention, is deteriorated. The composition of the dicarboxylic acid component of this hydrophobic copolymerizable polyester resin is as follows: aromatic dicarboxylic acid 60 to 99.5 mol%, aliphatic dicarboxylic acid and / or alicyclic dicarboxylic acid 0 to 40 mol%, polymerizable unsaturated It is preferable that it is 0.5-10 mol% of dicarboxylic acid containing a double bond. When the aromatic dicarboxylic acid is less than 60 mol%, or when the aliphatic dicarboxylic acid and / or the alicyclic dicarboxylic acid exceeds 40 mol%, the adhesion to the printing layer is lowered.

  Moreover, when the dicarboxylic acid containing a polymerizable unsaturated double bond is less than 0.5 mol%, it becomes difficult to efficiently graft the polymerizable unsaturated monomer to the hydrophobic copolymerizable polyester resin. On the other hand, when the amount exceeds 10 mol%, the viscosity is increased by the grafting reaction, and the uniform progress of the reaction is hindered. More preferably, the aromatic dicarboxylic acid is 70 to 98 mol%, the aliphatic dicarboxylic acid and / or the alicyclic dicarboxylic acid is 0 to 30 mol%, and the dicarboxylic acid containing a polymerizable unsaturated double bond is 2 to 7 mol%. It is.

  Examples of the aromatic dicarboxylic acid include terephthalic acid, isophthalic acid, orthophthalic acid, naphthalenedicarboxylic acid, biphenyldicarboxylic acid and the like. It is preferable not to use a hydrophilic group-containing dicarboxylic acid such as 5-sodium sulfoisophthalic acid because the blocking resistance, which is the object of the present invention, decreases. Examples of the aliphatic dicarboxylic acid include succinic acid, adipic acid, azelaic acid, sebacic acid, dodecanedioic acid, and dimer acid. Examples of the alicyclic dicarboxylic acid include 1,4-cyclohexanedicarboxylic acid, 1, Examples include 3-cyclohexanedicarboxylic acid, 1,2-cyclohexanedicarboxylic acid and acid anhydrides thereof. Examples of dicarboxylic acids containing polymerizable unsaturated double bonds include α, β-unsaturated dicarboxylic acids, fumaric acid, maleic acid, maleic anhydride, itaconic acid, citraconic acid, unsaturated double bonds Examples of the alicyclic dicarboxylic acid to be used include 2,5-norbornene dicarboxylic acid anhydride and tetrahydrophthalic anhydride. Of these, fumaric acid, maleic acid, and 2,5-norbornene dicarboxylic acid are preferred from the viewpoint of polymerizability.

  On the other hand, examples of the glycol component include aliphatic glycols having 2 to 10 carbon atoms and / or alicyclic glycols having 6 to 12 carbon atoms and / or ether bond-containing glycols. Examples of the aliphatic glycol having 2 to 10 carbon atoms include ethylene glycol, 1,2-propylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, neopentyl glycol, 1,6 -Hexanediol, 3-methyl-1,5-pentanediol, 1,9-nonanediol, 2-ethyl-2-butylpropanediol, and the like. Examples of the alicyclic glycol having 6 to 12 carbon atoms include 1,4-cyclohexanedimethanol.

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

  In the hydrophobic copolymerizable polyester resin, 0 to 5 mol% of a trifunctional or higher polycarboxylic acid and / or polyol can be copolymerized. As the trifunctional or higher polycarboxylic acid, (anhydrous) Trimellitic acid, (anhydrous) pyromellitic acid, (anhydrous) benzophenone tetracarboxylic acid, trimesic acid, ethylene glycol bis (anhydro trimellitate), glycerol tris (anhydro trimellitate) and the like are used. On the other hand, glycerin, trimethylolethane, trimethylolpropane, pentaerythritol and the like are used as the trifunctional or higher functional polyol. The tri- or higher functional polycarboxylic acid and / or polyol is copolymerized in the range of 0 to 5 mol%, preferably 0 to 3 mol% with respect to the total acid component or the total glycol component. Gelation during polymerization tends to occur, which is not preferable. The molecular weight of the hydrophobic copolymerizable polyester resin is preferably in the range of 5000 to 50000 on a weight average. If the molecular weight is less than 5,000, the adhesiveness of the printed layer may be lowered. Conversely, if it exceeds 50,000, problems such as gelation during polymerization may occur.

(Graft site of polyester graft copolymer)
The polymerizable unsaturated monomer to be grafted to the hydrophobic copolymerizable polyester resin is a hydrophilic radical polymerizable monomer, and is a radical polymerization having a hydrophilic group or a group that can be changed to a hydrophilic group later. It is a possible monomer. Examples of the hydrophilic group include a carboxyl group, a hydroxyl group, a phosphoric acid group, a phosphorous acid group, a sulfonic acid group, an amide group, and a quaternary ammonium base. On the other hand, examples of the group that can be changed to a hydrophilic group include an acid anhydride group, a glycidyl group, and a chloro group. Among these groups, a carboxyl group is preferable from the viewpoint of increasing the water dispersibility and the acid value of the graft copolymer. Accordingly, it is desirable to include at least one acid anhydride having a double bond as the polymerizable unsaturated monomer.

  Examples of the polymerizable unsaturated monomer include fumaric acid, monoethyl fumarate, diethyl fumarate, diester of fumaric acid such as dibutyl fumarate; maleic acid and its anhydride, monoethyl maleate, diethyl maleate Monoester or diester of maleic acid such as dibutyl maleate; itaconic acid and its anhydride, monoester or diester of itaconic acid; maleimide such as phenylmaleimide; styrene, α-methylstyrene, t-butylstyrene, chloromethyl Styrene derivatives such as styrene; vinyltoluene, divinylbenzene and the like. Acrylic polymerizable monomers that are one of polymerizable unsaturated monomers include, for example, alkyl acrylate, alkyl methacrylate (the alkyl group is methyl, ethyl, n-propyl, isopropyl, n-butyl). Group, isobutyl group, t-butyl group, 2-ethylhexyl group, cyclohexyl group, phenyl group, benzyl group, phenylethyl group, etc.): 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl acrylate, 2- Hydroxypropyl methacrylate-containing acrylic monomer: acrylamide, methacrylamide, N-methyl methacrylamide, N-methyl acrylamide, N-methylol acrylamide, N-methylol methacrylamide, N, N-dimethylol acrylamide N-methoxymethylacrylamide, N-methoxymethylmethacrylamide, amide group-containing acrylic monomer of N-phenylacrylamide: N, N-diethylaminoethyl acrylate, amino group-containing acrylic monomer of N, N-diethylaminoethyl methacrylate : Glycidyl acrylate, epoxy group-containing acrylic monomer of glycidyl methacrylate: Acrylic monomers containing carboxyl groups or salts thereof such as acrylic acid, methacrylic acid and their salts (sodium salt, potassium salt, ammonium salt) It is done. However, acrylic polymerizable monomers are less preferred for use in the present invention because they are less effective in reducing the surface energy hydrogen bond strength component term (γsh) of the present invention. The polymerizable unsaturated monomer can be copolymerized using one or more kinds, but it is preferable that the polymerizable unsaturated monomer contains at least one acid anhydride having a double bond. Among the above monomers, maleic anhydride is preferably used as the acid anhydride having a double bond. Styrene is preferred as another polymerizable unsaturated monomer to be combined with maleic anhydride. These acid anhydride esters may also be included.

(Polymerization initiator and other additives)
As the graft polymerization initiator that can be used in the present invention, organic peroxides and organic azo compounds known to those skilled in the art can be used. Benzoyl peroxide, t-butylperoxypivalate as organic peroxide, 2,2′-azobisisobutyronitrile, 2,2′-azobis (2,4-dimethylvaleronitrile) as organic azo compound Etc. The amount of the polymerization initiator used for the graft polymerization is at least 0.2% by mass, preferably 0.5% by mass or more, based on the polymerizable unsaturated monomer. In addition to the polymerization initiator, a chain transfer agent for adjusting the chain length of the branched polymer, for example, octyl mercaptan, mercaptoethanol, 3-t-butyl-4-hydroxyanisole and the like may be used as necessary. In this case, it is desirable to add in the range of 0 to 5% by mass with respect to the polymerizable unsaturated monomer.

  The copolymer polyester preferably has water solubility or water dispersibility from the viewpoint of coatability. As such a copolyester, a copolyester having at least one group selected from the group consisting of sulfonic acid groups or alkali metal bases thereof (hereinafter referred to as sulfonic acid group-containing copolyester) is used. Is preferred.

  Here, the sulfonic acid group-containing copolymer polyester means a polyester in which at least one group selected from the group consisting of a sulfonic acid group or an alkali metal base thereof is bonded to a part of a dicarboxylic acid component or a glycol component. However, a co-polymer prepared by using an aromatic dicarboxylic acid component containing at least one group selected from the group consisting of a sulfonic acid group or an alkali metal base thereof in a ratio of 2 to 10 mol% with respect to the total acid component. Polymerized polyester is preferred.

  As an example of such a dicarboxylic acid, 5-sodium sulfoisophthalic acid is suitable. In this case, as other dicarboxylic acid components, terephthalic acid, isophthalic acid, phthalic acid, p-β-oxyethoxybenzoic acid, 2,6-naphthalenedicarboxylic acid, 4,4′-dicarboxydiphenyl, 4,4 ′ -Dicarboxybenzophenone, bis (4-carboxyphenyl) ethane, adipic acid, sebacic acid, cyclohexane-1,4-dicarboxylic acid and the like.

  In order to increase the surface hardness and maintain good blocking resistance, 96 to 90 mol% of the total acid content is preferably an aromatic dicarboxylic acid such as terephthalic acid or isophthalic acid. More preferably, 4 to 10 mol% of the aromatic dicarboxylic acid contains at least one group selected from the group consisting of the sulfonic acid groups or alkali metal bases thereof.

  As the glycol component for producing the sulfonic acid group-containing copolymer polyester, ethylene glycol is mainly used. In addition, addition of propylene glycol, butanediol, neopentyl glycol, diethylene glycol, cyclohexanedimethanol, bisphenol A ethylene oxide addition Products, polyethylene glycol, polypropylene glycol, polytetramethylene glycol, and the like can be used. Among them, it is preferable to use ethylene glycol, propylene glycol, butanediol, neopentyl glycol, diethylene glycol, cyclohexane dimethanol or the like as a copolymerization component in terms of improving compatibility with polystyrene sulfonate.

  In addition, a dicarboxylic acid component or glycol component containing a small amount of an amide bond, a urethane bond, an ether bond, a carbonate bond, or the like may be included as a copolymer component of the copolymer polyester. Furthermore, in order to improve the surface hardness of the resulting coating film, a monomer containing a multi-carboxyl group such as trimellitic acid, trimesic acid, pyromellitic acid, trimellitic anhydride, pyromellitic anhydride is contained in a proportion of 5 mol% or less. It can also be used as a copolymerization component of the polyester. When these multi-carboxyl group-containing monomers exceed 5 mol%, the resulting sulfonic acid group-containing copolymer polyester becomes thermally unstable and is unfavorably easily gelled.

  The sulfonic acid group-containing copolymer polyester is obtained, for example, by esterification, transesterification, polycondensation reaction, etc. by a conventional method using the dicarboxylic acid component, the glycol component, and, if necessary, a multi-carboxyl group-containing monomer. be able to. The obtained sulfonic acid group-containing copolymer polyester is heated and stirred together with a solvent such as n-butyl cellosolve, and can be used as an aqueous solution or aqueous dispersion by gradually adding water while stirring.

(Polycarbonate polyurethane)
In the present invention, polyurethane imparts the flexibility of the easily adhesive layer and is added for excellent moldability. However, when the flexibility due to polyurethane is increased, blocking resistance and heat-and-moisture resistance in high-speed processing under heating conditions may further decrease. Therefore, in the present invention, polycarbonate polyurethane is used as the polyurethane.

  Polyurethane resins are broadly classified into polyester-based polyurethane resins, polyether-based polyurethane resins, and polycarbonate-based polyurethane resins. Polyester-based polyurethane resins are easily hydrolyzed in a humid heat environment, and polyether-based polyurethane resins are highly hygroscopic. The film strength of the easy-adhesion layer tends to decrease and the adhesiveness is insufficient. On the other hand, the polycarbonate-based urethane resin has excellent moisture and heat resistance because it has a polycarbonate structure as a hard segment. This is the reason why the polycarbonate-based polyurethane is used in the present invention.

  As the polycarbonate-based polyurethane resin, a polycarbonate diol, an aliphatic and / or alicyclic diisocyanate, and a polymer to which a chain extender is added as necessary can be used. Note that these urethane constituents can be identified by nuclear magnetic resonance analysis or the like.

  The polycarbonate diol is represented by the following general formula.

HO — [— R—O—COO—] _n —R—OH
(R is an aliphatic or alicyclic substituent)

  The polycarbonate diol is obtained, for example, by reacting one or more compounds selected from the group consisting of alkylene carbonate, diaryl carbonate, and dialkyl carbonate with diols and / or polyether polyols.

  Examples of the alkylene carbonate include ethylene carbonate, 1,2-propylene carbonate, 1,2-butylene carbonate and the like.

  Examples of diaryl carbonates include diphenyl carbonate, phenyl-naphthyl carbonate, dinaphthyl carbonate, 4-methyl diphenyl carbonate, 4-ethyl diphenyl carbonate, 4-propyl diphenyl carbonate, 4,4'-dimethyl-diphenyl carbonate, 4,4 Examples include '-diethyl-diphenyl carbonate and 4,4'-dipropyl-diphenyl carbonate.

  Examples of dialkyl carbonates include dimethyl carbonate, diethyl carbonate, di-n-propyl carbonate, diisopropyl carbonate, di-n-butyl carbonate, diisobutyl carbonate, di-t-butyl carbonate, di-n-amyl carbonate, diisoamyl carbonate. Etc.

  As a co-reactant for these carbonates, as examples of diols, ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, 2- Methyl-1,3-propanediol, neopentyl glycol, 2-methyl-pentanediol, 3-methyl-pentanediol, 2,2,4-trimethyl-1,6-hexanediol, 2,3,5-trimethylpentane Diol etc. are mentioned.

  Examples of polyether polyols include polytetramethylene glycol obtained by ring-opening polymerization of tetrahydrofuran and alkylene oxide adducts of diols. Examples of diols used herein include, for example, ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, isomer pentanediols, and isomer hexane. Diols or octanediols such as 2-ethyl-1,3-hexanediol, 1,2-bis (hydroxymethyl) -cyclohexanone, 1,3-bis (hydroxymethyl) -cyclohexanone, 1,4-bis (hydroxymethyl) ) -Cyclohexanone, trimethylolpropane, glycerin and the like. Examples of alkylene oxides include ethylene oxide, propylene oxide, 1,2-butylene oxide, 1,3-butylene oxide, 2,3-butylene oxide, and tetrahydrofuran. , Styrene oxide and epichlorohydrin and the like, which are also possible to use a mixture of two or more.

  The diols and polyether polyols described above may be used alone or in combination of two or more. Any of these can react with one or more compounds selected from the group consisting of the aforementioned alkylene carbonates, diaryl carbonates, and dialkyl carbonates by known methods to form polycarbonate diols.

  In the present invention, the composition molar ratio of the polycarbonate polyol, which is a constituent component of urethane, is preferably 3 to 100 mol%, and preferably 5 to 50 mol% when the total polyisocyanate component of urethane is 100 mol%. It is more preferable that the content is 6 to 20 mol%. When the composition molar ratio is low, the heat and moisture resistance effect of the polycarbonate polyol may not be obtained. Moreover, when the said composition molar ratio is high, adhesiveness may fall.

  Examples of the polyisocyanate that is a component of the urethane of the present invention include, for example, isomers of toluylene diisocyanate, aromatic diisocyanates such as 4,4-diphenylmethane diisocyanate, aromatic aliphatic diisocyanates such as xylylene diisocyanate, and isophorone. Diisocyanates and alicyclic diisocyanates such as 4,4-dicyclohexylmethane diisocyanate, 1,3-bis (isocyanatomethyl) cyclohexane, hexamethylene diisocyanate, and aliphatic diisocyanates such as 2,2,4-trimethylhexamethylene diisocyanate, Alternatively, polyisocyanates obtained by adding one or more of these compounds with trimethylolpropane or the like in advance may be mentioned.

  Chain extenders include glycols such as ethylene glycol, diethylene glycol, 1,4-butanediol, neopentyl glycol and 1,6-hexanediol, polyhydric alcohols such as glycerin, trimethylolpropane, and pentaerythritol, ethylenediamine Diamines such as hexamethylenediamine and piperazine, aminoalcohols such as monoethanolamine and diethanolamine, thiodiglycols such as thiodiethylene glycol, and water.

  The easy-adhesion layer of the present invention is preferably provided by an in-line coating method described later using an aqueous coating solution. Therefore, it is desirable that the urethane resin of the present invention is water-soluble. The “water-soluble” means that it dissolves in water or an aqueous solution containing less than 50% by mass of a water-soluble organic solvent.

  In order to impart water solubility to the urethane resin, a sulfonic acid (salt) group or a carboxylic acid (salt) group can be introduced (copolymerized) into the urethane molecular skeleton. Since the sulfonic acid (salt) group is strongly acidic and it may be difficult to maintain moisture resistance due to its hygroscopic performance, it is preferable to introduce a weakly acidic carboxylic acid (salt) group.

  In order to introduce a carboxylic acid (salt) group into a urethane resin, for example, as a polyol component, a polyol compound having a carboxylic acid group such as dimethylolpropionic acid or dimethylolbutanoic acid is introduced as a copolymer component to form a salt. Neutralize with an agent. Specific examples of the salt forming agent include trialkylamines such as ammonia, trimethylamine, triethylamine, triisopropylamine, tri-n-propylamine, tri-n-butylamine, N such as N-methylmorpholine and N-ethylmorpholine. -N-dialkylalkanolamines such as alkylmorpholines, N-dimethylethanolamine, N-diethylethanolamine and the like. These can be used alone or in combination of two or more.

  In order to impart water solubility, when a polyol compound having a carboxylic acid (salt) group is used as a copolymerization component, the composition molar ratio of the polyol compound having a carboxylic acid (salt) group in the urethane resin is the same as that of the urethane resin. When the total polyisocyanate component is 100 mol%, it is preferably 3 to 60 mol%, more preferably 10 to 40 mol%. If the composition molar ratio is less than 3 mol%, water dispersibility may be difficult.

  In the present invention, the glass transition point (Tig) of the polycarbonate-based polyurethane is preferably controlled within a specific range. That is, the glass transition point (Tig) of the polyurethane of the present invention has a lower limit of 40 ° C., preferably 50 ° C., and an upper limit of 100 ° C., preferably 90 ° C. When the glass transition point (Tig) of the polyurethane resin is less than 40 ° C., the blocking resistance may be lowered. On the other hand, when the temperature exceeds 100 ° C., the flexibility and adhesiveness of the easy-adhesion layer may decrease. In order to control the glass transition point (Tig) of the polyurethane within the above range, the following polyol component or molecular weight of the polyurethane can be appropriately selected and adjusted.

  In the present invention, the blending ratio of the copolymer polyester and the polyurethane is such that the polyester / polyurethane (mass ratio) = 80 / 20-30 / 70 is preferable. The blending ratio is more preferably 75/25 to 40/60. When the copolyester / polyurethane (mass ratio) = 100/0 to 90/10, the flexibility of the easy-adhesion layer may be lowered, and when 20/80 to 0/100, the blocking resistance and the adhesion may be lowered.

  The easy-adhesion layer of the present invention is mainly composed of a polyester that exhibits suitable adhesion to a base film made of polyester and polyurethane that is highly compatible with printing inks, and therefore has excellent initial adhesion. Indicates. Furthermore, a polyester-based graft copolymer capable of forming a high degree of self-crosslinking property is used as the polyester, and a polycarbonate-based polyurethane that is hardly hydrolyzed is used as the polyurethane. Therefore, it is possible to maintain not only initial adhesion but also excellent adhesion (moisture heat resistance) even in a wet heat environment. The present inventor considers that the combination of the polyester-based graft copolymer and the polycarbonate-based polyurethane is particularly suitable for imparting wet heat resistance as follows. That is, the polyester-based graft copolymer of the present invention has an acid anhydride as a constituent component as a side chain. On the other hand, the polyurethane of the present invention has a carbonate group. These side chains and carbonate groups exhibit a hydrogen bond-like interaction, and it is considered that the durability as an easy adhesion layer is exhibited to a higher degree. In any case, in the present invention, by using a polyester-based graft copolymer and a polycarbonate-based polyurethane as the easy-adhesion layer, the characteristics excellent in adhesion and heat-and-moisture resistance are exhibited.

(Crosslinking agent)
From the viewpoint of blocking resistance, the easy-adhesion layer of the present invention preferably contains a crosslinking agent. Thereby, an appropriate cross-linked structure is formed in the easy-adhesion layer, and therefore the addition of a cross-linking agent is suitable for imparting moisture heat resistance. The blending ratio of the crosslinking agent is preferably 5 to 40 parts by mass, more preferably 8 to 25 parts by mass with respect to 100 parts by mass of the total amount of the copolyester and polyurethane. If the blending ratio of the crosslinking agent is less than 5 parts by mass with respect to 100 parts by mass of the total amount of the copolymerized polyester and polyurethane, the blocking resistance may be lowered or the adhesiveness may be lowered. Conversely, when it exceeds 40 parts by mass, the flexibility for following the moldability may be reduced.

  Examples of the cross-linking agent include phenol formaldehyde resins of condensates with formaldehyde such as alkylated phenols and cresols; adducts of urea, melamine, benzoguanamine, and the like with formaldehyde, and the adducts having 1 to 6 carbon atoms. An amino resin such as an alkyl ether compound composed of alcohol; a polyfunctional epoxy compound; a polyfunctional isocyanate compound; a blocked isocyanate compound; a polyfunctional aziridine compound;

  Examples of the phenol formaldehyde resin include alkylated (methyl, ethyl, propyl, isopropyl or butyl) phenol, p-tert-amylphenol, 4,4′-sec-butylidenephenol, p-tert-butylphenol, o-, m-, p-cresol, p-cyclohexylphenol, 4,4'-isopropylidenephenol, p-nonylphenol, p-octylphenol, 3-pentadecylphenol, phenol, phenyl-o-cresol, p-phenylphenol, xylenol, etc. And the condensates of phenols and formaldehyde.

  Examples of amino resins include methoxylated methylol urea, methoxylated methylol N, N-ethyleneurea, methoxylated methylol dicyandiamide, methoxylated methylol melamine, methoxylated methylol benzoguanamine, butoxylated methylol melamine, butoxylated methylol benzoguanamine, and the like. Are preferably methoxylated methylol melamine, butoxylated methylol melamine, methylolated benzoguanamine, and the like.

  Examples of the polyfunctional epoxy compound include diglycidyl ether of bisphenol A and oligomer thereof, diglycidyl ether of hydrogenated bisphenol A and oligomer thereof, orthophthalic acid diglycidyl ester, isophthalic acid diglycidyl ester, terephthalic acid diglycidyl ester, p-oxybenzoic acid diglycidyl ester, tetrahydrophthalic acid diglycidyl ester, hexahydrophthalic acid diglycidyl ester, succinic acid diglycidyl ester, adipic acid diglycidyl ester, sebacic acid diglycidyl ester, ethylene glycol diglycidyl ether, propylene Glycol diglycidyl ether, 1,4-butanediol diglycidyl ether, 1,6-hexanediol diglycidyl ether and Polyalkylene glycol diglycidyl ethers, trimellitic acid triglycidyl ester, triglycidyl isocyanurate, 1,4-diglycidyloxybenzene, diglycidyl propylene urea, glycerol triglycidyl ether, trimethylolpropane triglycidyl ether, pentaerythritol triglycidyl Examples include ether, triglycidyl ether of glycerol alkylene oxide adduct, and the like.

  As the polyfunctional isocyanate compound, a low-molecular or high-molecular aromatic or aliphatic diisocyanate or a trivalent or higher polyisocyanate can be used. Examples of the polyisocyanate include tetramethylene diisocyanate, hexamethylene diisocyanate, toluene diisocyanate, diphenylmethane diisocyanate, hydrogenated diphenylmethane diisocyanate, xylylene diisocyanate, hydrogenated xylylene diisocyanate, isophorone diisocyanate, and trimers of these isocyanate compounds. Furthermore, an excess amount of these isocyanate compounds and low molecular active hydrogen compounds such as ethylene glycol, propylene glycol, trimethylolpropane, glycerin, sorbitol, ethylenediamine, monoethanolamine, diethanolamine, triethanolamine, or polyester polyols, poly The terminal isocyanate group containing compound obtained by making it react with polymer active hydrogen compounds, such as ether polyols and polyamides, can be mentioned.

  Among the crosslinking agents, a blocked isocyanate crosslinking agent is preferable as the crosslinking agent used in the present invention. By adding a blocked isocyanate-based crosslinking agent, it becomes possible to achieve both high adhesiveness and blocking resistance.

  The blocked isocyanate crosslinking agent can be prepared by subjecting the isocyanate compound and the blocking agent to an addition reaction by a conventionally known appropriate method. Examples of the isocyanate blocking agent include phenols such as phenol, cresol, xylenol, resorcinol, nitrophenol, and chlorophenol; thiophenols such as thiophenol and methylthiophenol; oximes such as acetoxime, methyl etiketooxime, and cyclohexanone oxime. Alcohols such as methanol, ethanol, propanol and butanol; halogen-substituted alcohols such as ethylene chlorohydrin and 1,3-dichloro-2-propanol; tertiary alcohols such as t-butanol and t-pentanol ; Lactams such as ε-caprolactam, δ-valerolactam, γ-butyrolactam, β-propyllactam; aromatic amines; imides; acetylacetone, acetoacetate Active methylene compounds such as malonic acid ethyl ester; mercaptans; imines; ureas; diaryl compounds; and sodium bisulfite and the like.

  It is preferable that isocyanate group content in a block isocyanate type crosslinking agent is 3.0-15.0 mass%. The isocyanate group content in the blocked isocyanate crosslinking agent is more preferably 4.0 to 10.0% by mass, further preferably 4.5 to 9.0% by mass, and 5.0 to 8. More preferably, it is 0 mass%. If the isocyanate group content in the blocked isocyanate crosslinking agent is less than 3.0% by mass, the ink adhesion deteriorates, which is not preferable. On the other hand, if it exceeds 15.0% by mass, the adhesiveness deteriorates, which is not preferable.

  In addition, when using the said block isocyanate type crosslinking agent, it evaluates as a reproduction | regeneration isocyanate group (reproduction | regeneration NCO) content which reproduces | regenerates and evaluates by the below-mentioned method.

(particle)
In this invention, in order to improve the blocking resistance of an easily bonding layer, it is also a preferable aspect to add particle | grains to an easily bonding layer. Examples of the particles contained in the easy-adhesion layer in the present invention include titanium oxide, barium sulfate, calcium carbonate, calcium sulfate, silica, alumina, talc, kaolin, clay and the like, or a mixture thereof. Inorganic particles such as calcium phosphate, mica, hectorite, zirconia, tungsten oxide, lithium fluoride, calcium fluoride and other inorganic particles, styrene, acrylic, melamine, benzoguanamine, silicone, etc. Examples include organic polymer particles.

  The average particle size of the sex particles in the easy-adhesion layer (number-based average particle size by SEM; the same applies hereinafter) is preferably 0.04 to 2.0 μm, more preferably 0.1 to 1.0 μm. If the average particle size of the inert particles is less than 0.04 μm, the formation of irregularities on the film surface becomes insufficient, so that the handling properties such as the slipping property and the winding property of the film are lowered, and the molding is performed. May also decrease. On the other hand, if it exceeds 2.0 μm, the haze of the film deteriorates, which is not preferable. In order to obtain high transparency, the particle concentration in the easy-adhesion layer is preferably 0.01 to 1.0% by mass, more preferably 0.05 to 0.5% by mass in the solid component. .

  In the present invention, the thickness of the easy-adhesion layer can be appropriately set in the range of 0.001 to 1.00 μm, but in order to achieve both high transparency and adhesiveness, the range of 0.01 to 0.10 μm. Is more preferably 0.02 to 0.09 μm, and still more preferably 0.03 to 0.08 μm. Adhesiveness will become inadequate that the thickness of an easily bonding layer is less than 0.01 micrometer. If the thickness of the easy-adhesion layer exceeds 0.10 μm, when the easy-adhesion layer contains particles, the haze of the film is deteriorated, and high transparency may not be obtained.

  In the coating liquid of the present invention, known additives, for example, antioxidants, heat stabilizers, weathering stabilizers, UV absorbers, organic lubricants, pigments, dyes, organics, as long as the effects of the present invention are not impaired. Alternatively, inorganic particles, an antistatic agent, a nucleating agent, or the like may be added.

(Base film)
(Copolymerized polyester)
As the base film of the present invention, a copolymer polyester is used as a constituent component from the viewpoint of high moldability. Examples of the copolyester include (a) a copolyester composed of an aromatic dicarboxylic acid component, ethylene glycol, and a glycol component containing a branched aliphatic glycol or alicyclic glycol, or (b) terephthalic acid and isophthalic acid. A copolyester composed of an aromatic dicarboxylic acid component containing an acid and a glycol component containing ethylene glycol is preferred. Moreover, it is preferable from the point which improves the moldability that the polyester which comprises a biaxially-oriented polyester film contains a 1, 3- propanediol unit or a 1, 4- butanediol unit as a glycol component further. In the case of (a) above, the copolymerization polyester used in the present invention is preferably added with a copolymerization component so that the proportion of ethylene glycol in the total glycol component is 20 mol% to 95 mol%. The lower limit of the proportion of ethylene glycol in the total glycol component is preferably 30 mol%, more preferably 40 mol%, and the upper limit is preferably 90 mol%, more preferably 80 mol%, still more preferably. Is 70 mol%. In the case of the above (b), the copolymerized polyester used in the present invention is added with a copolymer component such that the proportion of terephthalic acid in the total aromatic dicarboxylic acid component is 50 mol% to 95 mol%. It is preferable. The lower limit of the proportion of terephthalic acid in the total aromatic dicarboxylic acid component is preferably 60 mol%, more preferably 70 mol%, and the upper limit is preferably 90 mol%.

  In the present invention, as the film raw material, any method of copolymerized polyester alone, one or more homopolyesters or a blend of copolymerized polyesters, or a combination of homopolyester and copolymerized polyester is possible. Among these, the blending method is preferable from the viewpoint of suppressing the lowering of the melting point.

  When using a copolymer polyester composed of an aromatic dicarboxylic acid component, ethylene glycol, and a glycol component containing a branched aliphatic glycol or alicyclic glycol as the copolymer polyester, the aromatic dicarboxylic acid component is Terephthalic acid, isophthalic acid, naphthalenedicarboxylic acid or ester-forming derivatives thereof are suitable, and the amount of terephthalic acid and / or naphthalenedicarboxylic acid component relative to the total dicarboxylic acid component is 70 mol% or more, preferably 85 mol% or more. Particularly preferred is 95 mol% or more, and particularly preferred is 100 mol%.

  Examples of branched aliphatic glycols include neopentyl glycol, 1,2-propanediol, 1,3-propanediol, 1,4-butanediol, and the like. Examples of the alicyclic glycol include 1,4-cyclohexanedimethanol and tricyclodecane dimethylol.

  Among these, neopentyl glycol and 1,4-cyclohexanedimethanol are particularly preferable. Furthermore, in the present invention, it is a more preferable embodiment that 1,3-propanediol or 1,4-butanediol is used as a copolymerization component in addition to the glycol component. Use of these glycols as a copolymerization component is suitable for imparting the above-mentioned properties, and is also excellent in transparency and heat resistance, and from the viewpoint of improving the adhesion with the adhesion modified layer. Is also preferable.

  When the copolymer polyester is composed of an aromatic dicarboxylic acid component containing terephthalic acid and isophthalic acid and a glycol component containing ethylene glycol, the amount of ethylene glycol is based on the total glycol component. It is 70 mol% or more, preferably 85 mol% or more, particularly preferably 95 mol% or more, and particularly preferably 100 mol%. As the glycol component other than ethylene glycol, the above-mentioned branched aliphatic glycol, alicyclic glycol, or diethylene glycol is preferable.

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

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

  The copolyester preferably has an intrinsic viscosity of 0.50 dl / g or more, more preferably 0.55 dl / g or more, and particularly preferably 0.00 from the viewpoint of moldability, adhesiveness, and film formation stability. 60 dl / g or more. If the intrinsic viscosity is less than 0.50 dl / g, the moldability tends to decrease. In addition, when a filter for removing foreign substances is provided in the melt line, the upper limit of the intrinsic viscosity is preferably 1.0 dl / g from the viewpoint of ejection stability during extrusion of the molten resin.

(Polyester resin used as film raw material)
In the present invention, one or more homopolyesters or copolymerized polyesters are used as film raw materials, and these are blended to form a film, thereby maintaining the same flexibility as when only the copolymerized polyester is used. However, transparency and high melting point (heat resistance) can be realized. In addition, when only a high melting point homopolyester (for example, polyethylene terephthalate) is used, it is possible to realize a melting point (heat resistance) having no flexibility and practical problem while maintaining high transparency.

  In addition, blending at least one or more of the above copolyester and a homopolyester other than polyethylene terephthalate (for example, polytetramethylene terephthalate or polybutylene terephthalate) and using it as a raw material for the polyester-based resin film roll of the present invention Further, it is further preferable from the viewpoint of moldability.

  In the present invention, the film raw material is a polyester resin obtained by blending a copolyester alone or one or more homopolyesters or copolyesters. It is preferable that the polyester-type resin used for this invention contains 5-50 mass% of copolymerization components.

  The melting point of the polyester resin is preferably 180 to 250 ° C. from the viewpoint of heat resistance and moldability. By controlling the type and composition of the polymer to be used and the film forming conditions within the range of the melting point, a balance between moldability and finish can be achieved, and a high-quality molded product can be produced economically. Here, the melting point is an endothermic peak temperature at the time of melting, which is detected at the time of primary temperature rise in so-called differential scanning calorimetry (DSC). The melting point was determined by measuring at a heating rate of 20 ° C./min using a differential scanning calorimeter (DSC6200, manufactured by Seiko Instruments Inc.). The lower limit of the melting point is more preferably 190 ° C, further preferably 200 ° C, and particularly preferably 210 ° C or higher. If the melting point is less than 180 ° C, the heat resistance tends to deteriorate. Therefore, it may become a problem when exposed to high temperature during molding or use of a molded product.

  The upper limit of the melting point is preferably higher from the viewpoint of heat resistance, but when the polyethylene terephthalate unit is the main component, the film having a melting point exceeding 250 ° C. tends to deteriorate moldability. In addition, transparency tends to deteriorate. Furthermore, in order to obtain high moldability and transparency, it is preferable to control the upper limit of the melting point to 250 ° C.

  It is important that the polyester resin film of the present invention is a biaxially stretched film. In the present invention, solvent resistance and dimensional stability, which are disadvantages of an unstretched sheet, are improved by molecular orientation by biaxial stretching. That is, it is possible to improve the solvent resistance and heat resistance, which are disadvantages of the unstretched sheet, while maintaining good moldability of the unstretched sheet.

  What is necessary is just to set the thickness of the film of this invention suitably in the range of 10-500 micrometers according to a use. When using for the decoration use which provided the printing layer in the easily bonding layer, it is preferable that the thickness of the film of this invention is 15-200 micrometers, and it is more preferable that it is 25-125 micrometers.

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

  However, since the particles contained in the base film generally have a refractive index different from that of polyester, it causes a decrease in the transparency of the film. In order to improve the design of molded products, printing is often performed on the surface of the easy-adhesion layer before the film is molded. Therefore, it is preferable that the transparency of the film is high from the viewpoint of print clarity. Therefore, in applications where high transparency is required to provide a printed layer, the haze of the laminated polyester film for molding of the present invention is preferably 1.0% or less, more preferably 0.8% or less. Preferably, it is 0.5% or less.

  Therefore, in the present invention, in order to improve transparency, it is desirable that an easy-adhesion layer containing particles is provided on at least one surface of the base film, and that the base film does not substantially contain particles. Note that “substantially no particles are contained in the substrate film” means, for example, in the case of inorganic particles, a content that is below the detection limit when inorganic elements are quantified by fluorescent X-ray analysis. This is because contaminants derived from foreign substances may be mixed without intentionally adding particles to the base film.

  Further, as a preferred embodiment of the present invention, in order to obtain good transparency and stable workability (particularly surface friction characteristics), a polyester layer that is a film having a multilayer structure and contains fine particles only in the surface layer is used. It can also be used. Such a base film has a multilayer structure (a / b / a) in which a surface layer (a layer) containing inert particles is laminated on both sides of a central layer (b layer) by a coextrusion method. It is preferable to use a polyester film. The layers constituting the front and back surface layers may be the same or different, but in order to maintain the flatness of the base film, the polyester resin of the front and back surface layers should have the same configuration. Is desirable.

(Production method)
The laminated polyester film for molding of the present invention is preferably a biaxially oriented laminated polyester obtained by sequential biaxial stretching or simultaneous biaxial stretching. Hereinafter, the most preferred sequential biaxial stretching method will be described.

  First, the raw material pellets are sufficiently vacuum-dried. Next, the polyester sheet is melted at a temperature equal to or higher than the melting point using an extruder, the polyester sheet is extruded from a die by a co-extrusion method, and is closely adhered to a rotary cooling roll to obtain an unstretched polyester film. As a method of closely contacting the rotary cooling roll, a known electrostatic contact method, air knife method, air chamber method, or the like can be used. Moreover, you may cool by blowing air from the opposite surface of a rotary cooling roll as needed. The unstretched polyester film is guided to a roll-type longitudinal stretching machine and heated to 80 to 125 ° C., and then stretched 2.5 to 5.0 times in the longitudinal direction due to the peripheral speed difference of the roll to obtain a uniaxially stretched film. Longitudinal stretching may be carried out in one stage or in multiple stages.

  Thereafter, the uniaxially stretched polyester film was guided to a grip-type lateral stretching machine, heated to 80 to 180 ° C., stretched 2.5 to 5.0 times in the lateral direction, and then heat-set at 200 to 240 ° C. Then, if necessary, it is relaxed by 1 to 10% in the longitudinal direction and / or the transverse direction, and then wound up with a film winder to obtain a biaxially stretched polyester film.

As the step of applying the easy-adhesion layer, any method such as a method of applying before stretching of the film, a method of applying after longitudinal stretching, or a method of applying to the film surface after the orientation treatment is possible. The in-line coating method, which is applied before the completion of the crystal orientation of the material polyester film and then stretched in at least one direction and then completes the crystal orientation of the polyester film, can exhibit the effects of the present invention more remarkably. So is the preferred method

  As a method for providing an easy adhesion layer, a gravure coating method, a kiss coating method, a dip method, a spray coating method, a curtain coating method, an air knife coating method, a blade coating method, a reverse roll coating method and the like can be applied.

(Molded body)
The laminated polyester film for molding of the present invention has good moldability and adhesiveness. Therefore, it can use suitably as a molded object which carried out the shaping | molding process after giving a printing layer to the easily bonding layer surface. Thus, the molded object which laminated | stacked the printing layer on the easily bonding layer is suitable as a member for decorative molding, such as a member for building materials, and a base material for mobile phones. Also, a printing layer is applied to the easy-adhesion layer of the film, and an adhesive layer made of acrylic resin and an acrylic resin sheet having a thickness of about 0.1 to 5 mm are sequentially laminated, and a metal thin film layer is formed on the opposite surface. After being laminated, it can also be suitably used as a molded product obtained by molding.

  Such molded bodies include, for example, interior decorations and exterior decoration materials for automobiles, televisions, refrigerators, washing machines, stereos, home appliances such as portable devices, mirror products such as cosmetic compact mirrors, vehicles such as automobiles, It is suitable as a nameplate (including a display board and a panel) used for ships, aircrafts, buildings, play equipment (ski goggles, etc.), amusement devices, and other various mechanical devices. In particular, it is more suitable for uses under high-temperature and humid heat (bathrooms such as bathtubs, washstands, kitchens, sanitary, outdoor materials such as building materials, exteriors, solar panels, automobile interiors, and attics.

  Next, examples and comparative examples of the present invention will be shown. First, the measurement / evaluation method used in the present invention is shown below.

(1) Glass transition point (Tig)
The glass transition point (Tig) of the easy-adhesion layer was measured by scraping only the easy-adhesion layer from the easy-adhesion film.
The measurement was based on JIS K7121 and the glass transition start temperature (Tig) was calculated | required from the DSC curve using the differential scanning calorimeter (The Seiko Instruments Inc. make, DSC6200).
Measurement conditions (a) Measurement temperature range: 0 to 200 ° C
(B) Temperature increase rate: 20 ° C./min
(C) With nitrogen gas flow

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

(3) Haze Based on JIS-K7105, it evaluated using the integrating-sphere type light transmittance measuring apparatus (made by Nippon Denshoku Industries Co., Ltd.).

(4) Thickness of easy adhesion layer A film cross section is cut at right angles to the film surface with a microtome, a cross-sectional photograph of the film is taken with a transmission electron microscope (TEM), and the thickness of the resin component is measured on the photograph. The same measurement was performed 10 times at different locations, and the average of the measured values was taken as the resin component thickness (μm).

(5) Adhesive UV curable ink (manufactured by Seiko Advance Co., Ltd., UVA710 Black) is printed on the film surface (the surface of the easy-adhesion layer if an easy-adhesion layer is provided) with a Tetron screen (# 300 mesh). Then, UV exposure was performed at 500 mJ / cm ² .
Put a cross cut surface of 2 mm square 100 squares on the cured printed layer with a cutter knife, and paste cello tape (registered trademark) (manufactured by Nichiban Co., Ltd., CT-24) on it so that no air bubbles enter. Rub on it to make sure it adheres well. Thereafter, both ends of the ink surface before and after the adhesive tape (registered trademark) were not adhered to each other were pressed by hand and rapidly peeled in the 90 ° direction.
The ink surface after peeling was observed, and the adhesiveness was evaluated on the basis of the following four steps based on the ink residual ratio (treated as the number of pieces peeled even at a part of the square) in 100 squares. ○ was accepted. The easy adhesion referred to in the present invention is defined as having an ink residual ratio of 90% or more when the above evaluation is performed.
A: Residual rate 100% (no peeling at all)
○: Residual rate 90% or more and less than 100% (can be used practically without problems)
Δ: Residual rate of 70% or more and less than 90% (adhesion is slightly weak, and there is a possibility that problems may occur in practice)
X: Residual rate less than 70% (adhesion failure)

(6) Adhesiveness after moist heat Oxidized polymerization ink (manufactured by Jujo Kako Co., Ltd., black) and diluent solvent (manufactured by Jujo Kako Co., Ltd., Tetron) are diluted with ink: diluting solvent = 4: 1, and the film surface (easy When an adhesive layer was provided, the surface was printed on a surface of the easy adhesive layer) using a Tetron screen (# 250 mesh) and then dried in a gear oven at 65 ° C. for 15 minutes.
Next, the ink-printed film is placed in 80 ° C. hot water for 2 minutes. After taking out and wiping away moisture, it is air-dried for 3 hours or more. Subsequently, a crosscut surface of 100 mm square of 2 mm is put on the printing surface with a cutter knife, and cello tape (registered trademark) (manufactured by Nichiban Co., Ltd., CT-24) is pasted on the printed surface so that no air bubbles enter. Rub the top to make sure it is in close contact. Thereafter, both ends of the ink surface before and after the cellophane tape (registered trademark) were not adhered were pressed by hand, and the cross-cut surface was rapidly peeled in the 90 ° direction.
The ink surface after peeling was observed, and the adhesiveness was evaluated on the basis of the following four steps based on the ink residual ratio (treated as the number of pieces peeled even at a part of the square) in 100 squares. ○ was accepted. The easy adhesion referred to in the present invention is defined as having an ink residual ratio of 90% or more when the above evaluation is performed.
A: Residual rate 100% (no peeling at all)
○: Residual rate 90% or more and less than 100% (can be used practically without problems)
Δ: Residual rate of 70% or more and less than 90% (adhesion is slightly weak, and there is a possibility that problems may occur in practice)
X: Residual rate less than 70% (There is a problem with adhesiveness)

(7) Formability (elongation measurement)
The coating liquids A to W having a solid content of 11% by mass are applied to the unstretched laminated polyester film for molding with a Mayer bar # 10 and dried in a gear oven at 100 ° C. for 2 minutes. Further, heat is applied for 30 seconds in a gear oven at 200 ° C. to produce a coated film sample. Subsequently, the film is cut into strips having a length of 25 mm and a width of 80 mm, and squares having a length and width of 10 mm are written. A strip-shaped film sample is placed on a tensile tester, and the film sample piece is pulled at a speed of 90 mm / second by grasping both ends of the film while visually observing the appearance under an environment where the actual temperature of the film sample piece is 110 ° C. The length of the square when the occurrence of the problem was measured.
When the length of the film sample piece after the test was a, the elongation was calculated according to the following formula. (The length of the square of the film before the test is 10 mm)
Elongation (%) = (a−10) × 100/10
Here, those having an elongation of 300% or more are considered excellent in moldability, those having 200% or more and less than 300% are considered to have no problem in moldability, and those having an elongation of 100% or more and less than 200% have problems in moldability. It was judged that there was a problem in moldability if it was less than 100%.
A: Elongation is 300% or more (excellent moldability)
○: Elongation is 200% or more and less than 300% (no problem in moldability)
(Triangle | delta): Elongation is 100% or more and less than 200% (A problem may occur in moldability)
X: Elongation is less than 100% (there is a problem in moldability)

(8) NCO content (regenerated NCO content)
5-100 mg of a sample (adhesive layer) whose NCO content (regenerated NCO content) is to be measured is precisely weighed into an Erlenmeyer flask having a “sliding” opening. To the above Erlenmeyer flask, 25 ml of a 0.5 mol / l dibutylamine-monochlorobenzene solution is added, and ortho-dichlorobenzene and zeolite are added. Then, a “sliding” bulb condenser that fits the opening of the flask is attached. The above Erlenmeyer flask is placed on a previously prepared heating plate and reacted for 30 minutes after the solvent in the flask starts to boil. Then, after removing the Erlenmeyer flask from the heating plate and cooling to room temperature, 20 to 30 ml of methanol is poured from above the sliding ball tube cooler, and the inner wall of the cooler is washed away with the methanol. After removing the condenser from the Erlenmeyer flask, 100 ml of methanol and one drop of bromophenol blue indicator were put into the Erlenmeyer flask, and 0.5 mol / l hydrochloric acid standard solution was used for the contents of the flask. Perform back titration. At this time, the titer of the hydrochloric acid standard solution required for the titration of the sample is A (ml). A “blank” sample is obtained by performing the same operation as above except that the above heating is not performed. The blank is titrated as above. At this time, the titer of the hydrochloric acid standard solution required for the blank titration is defined as B (ml). The end point of the titration is the point at which the indigo color of the bromophenol blue indicator turns yellow. From the obtained results, the NCO content (regenerated NCO content) is calculated using the following formula.
Effective isocyanate content (mass%) = {(BA) × 42 × 0.5 × f} × 100 / (S × 1000)

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

(Preparation of water-dispersed polyester-based graft copolymer)
In a reactor equipped with a stirrer, thermometer, refluxing device and quantitative dropping device, 75 parts by mass of hydrophobic copolymer polyester, 56 parts by mass of methyl ethyl ketone and 19 parts by mass of isopropyl alcohol are heated and stirred at 65 ° C. Dissolved. After the resin was completely dissolved, 15 parts by mass of maleic anhydride was added to the polyester solution. Subsequently, a solution prepared by dissolving 10 parts by mass of styrene and 1.5 parts by mass of azobisdimethylvaleronitrile in 12 parts by mass of methyl ethyl ketone was dropped into the polyester solution at 0.1 ml / min, and stirring was further continued for 2 hours. After sampling for analysis from the reaction solution, 5 parts by mass of methanol was added. Next, 300 parts by mass of ion-exchanged water and 15 parts by mass of triethylamine were added to the reaction solution and stirred for 1.5 hours. Thereafter, the internal temperature of the reactor was raised to 100 ° C., and methyl ethyl ketone, isopropyl alcohol and excess triethylamine were distilled off to obtain a water-dispersed polyester graft copolymer. The obtained polyester-based graft copolymer was light yellow and transparent, and the glass transition point was 40 ° C. This resin was designated as a polyester-based graft copolymer (a1).

(Synthesis of polycarbonate urethane resin)
In a four-necked flask equipped with a reflux condenser, a nitrogen inlet tube, a thermometer, and a stirrer, 73.0 parts by mass of 1,3-cyclohexanebis (methyl isocyanate) as polyisocyanate and polyhexane having a number average molecular weight of 2000 Diol carbonate 112.7 parts by mass, neopentyl glycol 11.7 parts by mass, dimethylolpropionic acid 12.6 parts by mass, and as an organic solvent, acetonitrile 60 parts by mass, N-methylpyrrolidone 30 parts by mass, Under a nitrogen atmosphere, the temperature of the reaction solution was adjusted to 75 to 78 ° C., and 0.06 part by mass of stannous octylate was added as a reaction catalyst, and the reaction rate was reacted to 99% or more in 7 hours. Subsequently, this was cooled to 30 degreeC and the isocyanate group terminal prepolymer was obtained. Next, 450 g of water was added to a reaction vessel equipped with a homodisper capable of high-speed stirring, adjusted to 25 ° C., and added with an isocyanate group-terminated prepolymer while stirring and mixing at 2000 min ⁻¹ to disperse in water. did. Thereafter, an aqueous solution (b1) of a water-dispersible polycarbonate-based urethane resin having a solid content of 35% was prepared by removing a portion of acetonitrile and water under reduced pressure. The glass transition point (Tig) was 86 ° C.

(Preparation of coating solution A)
The ratio of the solid content of the polyester-based graft copolymer (a1) and water-dispersible polycarbonate-based urethane resin (b1) obtained above is polyester-based graft copolymer / polyurethane resin (mass ratio) = 95/5. In addition, the block isocyanate compound having an isocyanate group content (regenerated NCO) of 5.4% by mass is mixed to 20 parts by mass with respect to 100 parts by mass of the total amount of the polyester-based graft copolymer and the polyurethane resin. The total resin solids concentration is 3.8% by mass, and the silica particles having an average particle size of 1.0 μm are 0.44% by mass with respect to the total resin and the silica particles having an average particle size of 0.1 μm are based on the total resin. In order to contain 10% by mass, it was diluted with a mixed solvent of water / isopropyl alcohol (= 65/35; mass ratio) to obtain an aqueous coating agent.

(Manufacture of film raw materials)
Copolymer polyester chip having an intrinsic viscosity of 0.69 dl / g, comprising 100 mol% of terephthalic acid units as aromatic dicarboxylic acid components, 40 mol% of ethylene glycol units and 60 mol% of neopentyl glycol units as diol components. (A) and a polyethylene terephthalate chip (B) containing 0.04% by mass of silica having an intrinsic viscosity of 0.69 dl / g and an average particle diameter (SEM method, the same applies hereinafter) of 2.7 μm, respectively. I let you. Furthermore, the chip (A) and the chip (B) were mixed so as to have a mass ratio of 25:75.

(Manufacture of laminated film)
Subsequently, these chip mixtures were melt-extruded from the slit of the T die at 270 ° C. with an extruder, rapidly cooled and solidified on a chill roll having a surface temperature of 40 ° C., and at the same time, the amorphous mixture was adhered to the chill roll using an electrostatic application method. A stretched sheet was obtained.

  The obtained unstretched sheet was stretched 3.3 times at 90 ° C. in the longitudinal direction between the heating roll and the cooling roll.

  Subsequently, the aqueous coating liquid A shown above was applied to one side of the film by roll coating on the obtained uniaxially stretched film, and dried at 130 ° C. for 3 seconds to remove moisture.

  Thereafter, the end portion is continuously held by a clip and guided to a tenter, heated at a setting of 100 ° C., stretched 3.8 times, heat-treated at 230 ° C. for 5 seconds while being fixed in width, and further 205 By relaxing 5% in the width direction at 0 ° C., a laminated polyester film for molding having an easily adhesive layer coating thickness of 0.07 μm was obtained.

  The evaluation results of the obtained laminated polyester film are shown in Table 1.

(Preparation of coating solution B)
The ratio of the solid content of the polyester graft copolymer (a1) and the water dispersible polycarbonate urethane resin (b1) obtained above is polyester graft copolymer / polyurethane resin (mass ratio) = 80/20. In addition, the block isocyanate compound having an isocyanate group content (regenerated NCO) of 5.4% by mass with respect to 100 parts by mass of the total amount of the polyester-based graft copolymer and the polyurethane resin is mixed so as to be 20 parts by mass. The total resin solids concentration is 3.8% by mass, and the silica particles having an average particle size of 1.0 μm are 0.44% by mass with respect to the total resin and the silica particles having an average particle size of 0.1 μm are based on the total resin. In order to contain 10% by mass, it was diluted with a mixed solvent of water / isopropyl alcohol (= 65/35; mass ratio) to obtain an aqueous coating agent.

Example 2
In Example 1, a laminated polyester film having a coating thickness of 0.07 μm was obtained in the same manner as in Example 1 except that the coating liquid A was replaced with the coating liquid B. The characteristics and evaluation results of the obtained film are shown in Table 1.

(Preparation of coating solution C)
The ratio of the solid content of the copolyester resin liquid (a1) and polyurethane resin (b1) obtained above is copolyester resin / polyurethane resin (mass ratio) = 70/30, and the copolyester resin and It is mixed so that the isocyanate group content (regenerated NCO) is 5.4% by mass with respect to 100 parts by mass of the total amount of the polyurethane resin, and the mixed resin solid content concentration is 3.8% by mass. %, Particles having an average particle diameter of 1.0 μm as 0.44% by mass with respect to the total resin and 10% by mass of silica particles with an average particle diameter of 0.1 μm with respect to the total resin as water / It was diluted with a mixed solvent of isopropyl alcohol (= 65/35; mass ratio) to obtain an aqueous coating agent.

Example 3
A laminated polyester film in which the coating thickness of the easy adhesion layer was 0.07 μm was obtained in the same manner as in Example 2 except that the coating liquid B was replaced with the coating liquid C in Example 2. The characteristics and evaluation results of the obtained film are shown in Table 1.

(Preparation of coating solution D)
The ratio of the solid content of the copolyester resin liquid (a1) and polyurethane resin (b1) obtained above is copolyester resin / polyurethane resin (mass ratio) = 40/60, and the copolyester resin and It is mixed so that the isocyanate group content (regenerated NCO) is 5.4% by mass with respect to 100 parts by mass of the total amount of the polyurethane resin, and the mixed resin solid content concentration is 3.8% by mass. %, Particles having an average particle diameter of 1.0 μm as 0.44% by mass with respect to the total resin and 10% by mass of silica particles with an average particle diameter of 0.1 μm with respect to the total resin as water / It was diluted with a mixed solvent of isopropyl alcohol (= 65/35; mass ratio) to obtain an aqueous coating agent.

Example 4
In Example 2, except that the coating liquid B was replaced with the coating liquid D, a laminated polyester film having an easily adhesive layer with a coating thickness of 0.07 μm was obtained in the same manner as in Example 2. The characteristics and evaluation results of the obtained film are shown in Table 1.

(Preparation of coating solution E)
The ratio of the solid content of the copolyester resin liquid (a1) and polyurethane resin (b1) obtained above is copolyester resin / polyurethane resin (mass ratio) = 30/70, and the copolyester resin and It is mixed so that the isocyanate group content (regenerated NCO) is 5.4% by mass with respect to 100 parts by mass of the total amount of the polyurethane resin, and the mixed resin solid content concentration is 3.8% by mass. %, Particles having an average particle diameter of 1.0 μm as 0.44% by mass with respect to the total resin and 10% by mass of silica particles with an average particle diameter of 0.1 μm with respect to the total resin as water / It was diluted with a mixed solvent of isopropyl alcohol (= 65/35; mass ratio) to obtain an aqueous coating agent.

Example 5
In Example 2, except that the coating liquid B was replaced with the coating liquid E, the same procedure as in Example 2 was carried out to obtain a laminated polyester film having a coating thickness of the easy adhesion layer of 0.07 μm. The characteristics and evaluation results of the obtained film are shown in Table 1.

(Preparation of coating solution F)
The ratio of the solid content of the copolymerized polyester resin liquid (a1) and polyurethane resin (b1) obtained above is copolymerized polyester resin / polyurethane resin (mass ratio) = 10/90, and the copolymerized polyester resin and It is mixed so that the isocyanate group content (regenerated NCO) is 5.4% by mass with respect to 100 parts by mass of the total amount of the polyurethane resin, and the mixed resin solid content concentration is 3.8% by mass. %, Particles having an average particle diameter of 1.0 μm as 0.44% by mass with respect to the total resin and 10% by mass of silica particles with an average particle diameter of 0.1 μm with respect to the total resin as water / It was diluted with a mixed solvent of isopropyl alcohol (= 65/35; mass ratio) to obtain an aqueous coating agent.

Example 6
In Example 2, a laminated polyester film having a coating thickness of 0.07 μm was obtained in the same manner as in Example 2 except that the coating liquid B was replaced with the coating liquid F. The characteristics and evaluation results of the obtained film are shown in Table 1.

(Preparation of coating solution G)
The ratio of the solid content of the copolyester resin liquid (a1) obtained above and a polyurethane resin having a glass transition point of 85 ° C. (catalog value) (trade name Takelac W615, manufactured by Mitsui Takeda Chemical Co., Ltd.) is a copolyester resin. / Block polyurethane resin (mass ratio) = 80/20 and the isocyanate group content (regenerated NCO) is 5.4% by mass with respect to 100 parts by mass of the total amount of the copolyester resin and polyurethane resin A compound having a total resin solid content concentration of 3.8% by mass and silica particles having an average particle size of 1.0 μm as a particle is 0.44% by mass and the average particle size is 0. Diluted with a mixed solvent of water / isopropyl alcohol (= 65/35; mass ratio) so as to contain 10% by mass of 1 μm silica particles with respect to the total resin Thus, an aqueous coating agent was obtained.

Example 7
In Example 2, a laminated polyester film having an easy-adhesion layer applied thickness of 0.07 μm was obtained in the same manner as Example 2 except that the coating liquid B was replaced with the coating liquid G. The characteristics and evaluation results of the obtained film are shown in Table 1.

(Preparation of coating solution H)
The ratio of the solid content of the copolyester resin liquid (a1) obtained above and a polyurethane resin having a glass transition point of 85 ° C. (catalog value) (trade name Takelac W615, manufactured by Mitsui Takeda Chemical Co., Ltd.) is a copolyester resin. / Polyurethane resin (mass ratio) = 80/20 and 20 parts by mass of a polyisocyanate compound having an isocyanate group content of 12.4% by mass based on 100 parts by mass of the total amount of the copolyester resin and the polyurethane resin Silica having a total resin solids concentration of 3.8% by mass and silica particles having an average particle size of 1.0 μm as a particle and 0.44% by mass with respect to the total resin and an average particle size of 0.1 μm. Diluted with a mixed solvent of water / isopropyl alcohol (= 65/35; mass ratio) so as to contain 10% by mass of the particles with respect to the total resin. An agent was used.

Example 8
In Example 2, a laminated polyester film having a coating thickness of 0.07 μm was obtained in the same manner as in Example 2 except that the coating liquid B was replaced with the coating liquid H. The characteristics and evaluation results of the obtained film are shown in Table 1.

(Preparation of coating liquid I)
The ratio of the solid content of the copolyester resin liquid (a1) obtained above and a polyurethane resin having a glass transition point of 85 ° C. (catalog value) (trade name Takelac W615, manufactured by Mitsui Takeda Chemical Co., Ltd.) is a copolyester resin. / Polyurethane resin (mass ratio) = 80/20, and the isocyanate group content (regenerated NCO) is 7% by mass with respect to 100 parts by mass of the total amount of the copolyester resin and the polyurethane resin. The total resin solid content concentration is 3.8% by mass, silica particles having an average particle size of 1.0 μm are 0.44% by mass with respect to the total resin, and the average particle size is 0.1 μm. The silica particles were diluted with a mixed solvent of water / isopropyl alcohol (= 65/35; mass ratio) so as to contain 10% by mass of silica particles based on the total resin. An aqueous coating agent was obtained.

Example 9
In Example 2, a laminated polyester film having a coating thickness of 0.07 μm was obtained in the same manner as in Example 2 except that the coating liquid B was replaced with the coating liquid I. The characteristics and evaluation results of the obtained film are shown in Table 1.

(Preparation of coating solution J)
The ratio of the solid content of the copolyester resin liquid (a1) obtained above and a polyurethane resin having a glass transition point of 85 ° C. (catalog value) (trade name Takelac W615, manufactured by Mitsui Takeda Chemical Co., Ltd.) is a copolyester resin. / Block polyurethane resin (mass ratio) = 80/20, and the isocyanate group content (regenerated NCO) is 4.5 mass% with respect to 100 mass parts of the total amount of the copolyester resin and polyurethane resin A compound having a total resin solid content concentration of 3.8% by mass and silica particles having an average particle size of 1.0 μm as a particle is 0.44% by mass and the average particle size is 0. Diluted with a mixed solvent of water / isopropyl alcohol (= 65/35; mass ratio) so as to contain 10% by mass of 1 μm silica particles with respect to the total resin Thus, an aqueous coating agent was obtained.

Example 10
In Example 2, a laminated polyester film having a coating thickness of 0.07 μm was obtained in the same manner as in Example 2 except that the coating liquid B was replaced with the coating liquid J. The characteristics and evaluation results of the obtained film are shown in Table 1.

(Preparation of coating solution K)
The ratio of the solid content of the copolyester resin liquid (a1) obtained above and a polyurethane resin having a glass transition point of 85 ° C. (catalog value) (trade name Takelac W615, manufactured by Mitsui Takeda Chemical Co., Ltd.) is a copolyester resin. / Block polyurethane resin (mass ratio) = 80/20 and the isocyanate group content (regenerated NCO) is 3.0% by mass with respect to 100 parts by mass of the total amount of the copolyester resin and the polyurethane resin. A compound having a total resin solid content concentration of 3.8% by mass and silica particles having an average particle size of 1.0 μm as a particle is 0.44% by mass and the average particle size is 0. Diluted with a mixed solvent of water / isopropyl alcohol (= 65/35; mass ratio) so as to contain 10% by mass of 1 μm silica particles with respect to the total resin Thus, an aqueous coating agent was obtained.

Example 11
In Example 2, a laminated polyester film having an easy-adhesion layer applied thickness of 0.07 μm was obtained in the same manner as Example 2 except that the coating liquid B was replaced with the coating liquid K. The characteristics and evaluation results of the obtained film are shown in Table 1.

(Preparation of coating liquid L)
The ratio of the solid content of the copolyester resin liquid (a1) and polyurethane resin (b1) obtained above is copolyester resin / polyurethane resin (mass ratio) = 80/20, and the copolyester resin and Mixing so that the isocyanate group content is 5.4% by mass with respect to 100 parts by mass of the total amount of the polyurethane resin, and mixing the block isocyanate compound 40 parts by mass, the total resin solid content concentration is 3.8% by mass, as particles Water / isopropyl alcohol so that silica particles having an average particle diameter of 1.0 μm are contained in an amount of 0.44% by mass based on the total resin and silica particles having an average particle diameter of 0.1 μm are included in the total resin by 10% by mass. Was diluted with a mixed solvent (= 65/35; mass ratio) to obtain an aqueous coating agent.

Example 12
In Example 2, a laminated polyester film having an easily adhesive layer applied thickness of 0.07 μm was obtained in the same manner as Example 2 except that the coating liquid B was replaced with the coating liquid L. The characteristics and evaluation results of the obtained film are shown in Table 1.

(Preparation of coating solution M)
The ratio of the solid content of the copolyester resin liquid (a1) and polyurethane resin (b1) obtained above is copolyester resin / polyurethane resin (mass ratio) = 80/20, and the copolyester resin and Mixing so that the isocyanate group content is 5.4% by mass with respect to a total amount of 100 parts by mass of the polyurethane resin and 25 parts by mass of the blocked isocyanate compound, the total resin solid content concentration is 3.8% by mass, as particles Water / isopropyl alcohol so that silica particles having an average particle diameter of 1.0 μm are contained in an amount of 0.44% by mass based on the total resin and silica particles having an average particle diameter of 0.1 μm are included in the total resin by 10% by mass. Was diluted with a mixed solvent (= 65/35; mass ratio) to obtain an aqueous coating agent.

Example 13
In Example 2, a laminated polyester film having an easy-adhesion layer applied thickness of 0.07 μm was obtained in the same manner as Example 2 except that the coating liquid B was replaced with the coating liquid M. Table 2 shows the properties and evaluation results of the obtained film.

(Preparation of coating solution N)
The ratio of the solid content of the copolyester resin liquid (a1) and polyurethane resin (b1) obtained above is copolyester resin / polyurethane resin (mass ratio) = 80/20, and the copolyester resin and Mixing so that the isocyanate group content is 8 parts by mass with respect to 100 parts by mass of the total amount of the polyurethane resin, and the total resin solid content concentration is 3.8% by mass as particles. Water / isopropyl alcohol so that silica particles having an average particle diameter of 1.0 μm are contained in an amount of 0.44% by mass based on the total resin and silica particles having an average particle diameter of 0.1 μm are included in the total resin by 10% by mass. Was diluted with a mixed solvent (= 65/35; mass ratio) to obtain an aqueous coating agent.

Example 14
In Example 2, except that the coating liquid B was replaced with the coating liquid N, a laminated polyester film having an easily adhesive layer with a coating thickness of 0.07 μm was obtained in the same manner as in Example 2. The characteristics and evaluation results of the obtained film are shown in Table 1.

(Preparation of coating solution O)
The ratio of the solid content of the copolyester resin liquid (a1) and polyurethane resin (b1) obtained above is copolyester resin / polyurethane resin (mass ratio) = 80/20, and the copolyester resin and Mixing so that the isocyanate group content is 5 parts by mass with respect to 100 parts by mass of the total amount of the polyurethane resin, and the total resin solid content concentration is 3.8% by mass as particles. Water / isopropyl alcohol so that silica particles having an average particle diameter of 1.0 μm are contained in an amount of 0.44% by mass based on the total resin and silica particles having an average particle diameter of 0.1 μm are included in the total resin by 10% by mass. Was diluted with a mixed solvent (= 65/35; mass ratio) to obtain an aqueous coating agent.

Example 15
In Example 2, a laminated polyester film having an easy-adhesion layer applied thickness of 0.07 μm was obtained in the same manner as Example 2 except that the coating liquid B was replaced with the coating liquid O. The characteristics and evaluation results of the obtained film are shown in Table 1.

(Preparation of coating solution P)
The ratio of the solid content of the copolyester resin liquid (a1) and polyurethane resin (b1) obtained above is copolyester resin / polyurethane resin (mass ratio) = 80/20, and the copolyester resin and Mixing so that the isocyanate group content is 20 parts by mass with respect to 100 parts by mass of the total amount of polyurethane resin, and the total resin solid content concentration is 3.8% by mass as particles. Water / Isople so that silica particles having an average particle diameter of 1.4 μm are contained in an amount of 3.0% by mass with respect to the total resin and silica particles having an average particle diameter of 0.2 μm in an amount of 0.02% by mass with respect to the total resin. It was diluted with a mixed solvent of pill alcohol (= 65/35; mass ratio) to obtain an aqueous coating agent.

Example 16
In Example 2, except that the coating liquid B was replaced with the coating liquid P, the same procedure as in Example 2 was carried out to obtain a laminated polyester film having a coating thickness of the easy adhesion layer of 0.07 μm. The characteristics and evaluation results of the obtained film are shown in Table 1.

Example 17
A laminated polyester film similar to Example 1 was obtained except that the coating thickness of the easy adhesion layer was 0.2 μm. The characteristics and evaluation results of the obtained film are shown in Table 1.

Example 18
A laminated polyester film similar to Example 1 was obtained except that the coating thickness of the easy adhesion layer was 0.09 μm. The characteristics and evaluation results of the obtained film are shown in Table 1.

Example 19
A laminated polyester film similar to Example 1 was obtained except that the coating thickness of the easy adhesion layer was 0.04 μm. The characteristics and evaluation results of the obtained film are shown in Table 1.

Example 20
A laminated polyester film similar to Example 1 was obtained except that the coating thickness of the easy adhesion layer was 0.02 μm. Table 2 shows the properties and evaluation results of the obtained film.

(Coating solution Q preparation)
The ratio of the solid content of the copolyester resin liquid (a1) and polyurethane resin (b1) obtained above is copolyester resin / polyurethane resin (mass ratio) = 100/0, and copolyester resin 100 It is mixed so that the isocyanate group content is 5.4% by mass based on 20 parts by mass of the blocked isocyanate compound, and the total resin solid content concentration is 3.8% by mass. A mixed solvent of water / isopropyl alcohol (= 65) so as to contain 0.4 .mu.m of 0.0.mu.m and 10% by mass of silica particles having an average particle size of 0.1 .mu.m with respect to the total resin. / 35; mass ratio) to obtain an aqueous coating agent.

Comparative Example 1
In Example 2, except that the coating liquid B was replaced with the coating liquid Q, a laminated polyester film having a coating thickness of 0.07 μm was obtained in the same manner as in Example 2. The characteristics and evaluation results of the obtained film are shown in Table 1.

(Preparation of coating solution R)
The ratio of the solid content of the copolyester resin liquid (a1) and polyurethane resin (b1) obtained above is copolyester resin / polyurethane resin (mass ratio) = 0/100, and copolyester resin 100 It is mixed so that the isocyanate group content is 5.4% by mass based on 20 parts by mass of the blocked isocyanate compound, and the total resin solid content concentration is 3.8% by mass. A mixed solvent of water / isopropyl alcohol (= 65) so as to contain 0.4 .mu.m of 0.0.mu.m and 10% by mass of silica particles having an average particle size of 0.1 .mu.m with respect to the total resin. / 35; mass ratio) to obtain an aqueous coating agent.

Comparative Example 2
In Example 2, a laminated polyester film having an easy-adhesion layer applied thickness of 0.07 μm was obtained in the same manner as in Example 2 except that the coating liquid B was replaced with the coating liquid R. The characteristics and evaluation results of the obtained film are shown in Table 1.

(Preparation of coating solution S)
The ratio of the solid content of the copolymerized polyester resin liquid (a1) and polyurethane resin (b1) obtained above is copolymerized polyester resin / polyurethane resin (mass ratio) = 80/20, and the total resin solid content concentration is 3. 0.84% by mass, 0.44% by mass of silica particles having an average particle size of 1.0 μm as particles and 10% by mass of silica particles having an average particle size of 0.1 μm with respect to all resins The mixture was diluted with a mixed solvent of water / isopropyl alcohol (= 65/35; mass ratio) to obtain an aqueous coating agent.

Comparative Example 3
In Example 2, except that the coating liquid B was replaced with the coating liquid S, a laminated polyester film having a coating thickness of 0.07 μm was obtained in the same manner as in Example 2. Table 2 shows the properties and evaluation results of the obtained film.

(Preparation of coating solution T)
The proportion of the copolymerized polyester resin liquid (a1) obtained above and the temperature of 35 ° C. (catalog value) polyurethane resin (manufactured by Mitsui Takeda Chemicals Co., Ltd .: trade name Takelac W511) is a copolymerized polyester resin / polyurethane resin (mass Ratio) = 80/20, and mixed so that the isocyanate group content is 5.4% by mass and the blocked isocyanate compound is 20 parts by mass with respect to 100 parts by mass of the total amount of the copolyester resin and the polyurethane resin. The total resin solids concentration of 3.8% by mass and the silica particles having an average particle size of 1.0 μm as the particles are 0.44% by mass relative to the total resin, and the silica particles having an average particle size of 0.1 μm are used as the total resin. On the other hand, it was diluted with a mixed solvent of water / isopropyl alcohol (= 65/35; mass ratio) so as to contain 10% by mass to obtain an aqueous coating agent.

Comparative Example 4
In Example 2, a laminated polyester film having an easy-adhesion layer applied thickness of 0.07 μm was obtained in the same manner as in Example 2 except that the coating liquid B was replaced with the coating liquid T. The characteristics and evaluation results of the obtained film are shown in Table 1.

(Preparation of coating solution U)
Preparation of Copolyester Resin Coating solution U was prepared according to the following method. A reaction vessel was charged with 95 parts by weight of dimethyl terephthalate, 95 parts by weight of dimethyl isophthalate, 35 parts by weight of ethylene glycol, 145 parts by weight of neopentyl glycol, 0.1 part by weight of zinc acetate and 0.1 part by weight of antimony trioxide. The transesterification was carried out over 3 hours. Next, 6.0 parts by mass of 5-sodium sulfoisophthalic acid was added, and esterification was performed at 240 ° C. over 1 hour, and then at 250 ° C. under reduced pressure (10 to 0.2 mmHg) over 2 hours. A polycondensation reaction was performed to obtain a copolymerized polyester resin (a2) having a number average molecular weight of 19,500.
Preparation of polyurethane resin aqueous solution 100 parts by mass of polyester diol (OHV: 2000 eq / ton) having a composition of adipic acid // 1.6-hexanediol / neopentyl glycol (molar ratio: 4 // 2/3), After 41.4 parts by mass of diisocyanate was mixed and reacted at 80 to 90 ° C. for 1 hour under a nitrogen stream, the mixture was cooled to 60 ° C., 70 parts by mass of tetrahydrofuran was added and dissolved, and a urethane prepolymer solution (NCO / OH ratio: 2.2, free isocyanate group: theoretical value 3.56% by mass, measured value 3.30% by mass). Subsequently, the urethane prepolymer solution was brought to 40 ° C., then, 45.5 parts by mass of a 20% by mass aqueous sodium bisulfite solution was added, and the mixture was reacted at 40-50 ° C. for 30 minutes while vigorously stirring. After confirming the disappearance of the free isocyanate group content (in terms of solid content), it was diluted with emulsified water to obtain a polyurethane resin aqueous solution (b2) having a solid content of 20% by mass.
7.5 parts by mass of a 30% by mass aqueous dispersion of the obtained copolyester resin (a2), 11.3 parts by mass of the polyurethane resin aqueous solution (b2), and 0.03 of the catalyst (dibutyltin laurate). 39.8 parts by mass of water, 39.8 parts by mass of water, and 37.4 parts by mass of isopropyl alcohol were mixed. Further, 0.6 part by mass of a 10% by mass aqueous solution of a nonionic surfactant, 2.3 parts by mass of a 20% by mass aqueous dispersion of colloidal silica (average particle size 0.04 μm) as particles, and then 5% by mass The pH of the coating solution was adjusted to 6.2 with an aqueous sodium bicarbonate solution, and the solution was precisely filtered through a felt-type polypropylene filter having a filtration particle size (initial filtration efficiency: 95%) of 10 μm to prepare coating solution U.

Comparative Example 5
In Example 2, a laminated polyester film in which the coating thickness of the easy adhesion layer was 0.07 μm was obtained in the same manner as in Example 2 except that the coating liquid B was replaced with the coating liquid U. Table 1 shows the properties and evaluation results of the obtained single-layer film.

(Preparation of coating solution V)
The polyester-based graft copolymer (a1) obtained above has a solid content ratio of an ether-based polyurethane resin (trade name Takelac W6020, manufactured by Mitsui Takeda Chemical Co., Ltd.) having a glass transition point of 90 ° C. (catalog value). System graft copolymer / polyurethane resin (mass ratio) = 80/20, and the isocyanate group content (regenerated NCO) is 5. with respect to 100 parts by mass of the total amount of the polyester system graft copolymer and polyurethane resin. The block isocyanate compound of 4% by mass is mixed so as to be 20 parts by mass, the total resin solid content concentration is 3.8% by mass, and the silica particles have an average particle diameter of 1.0 μm as the total resin. Water / isopropyl alcohol so as to contain 44% by mass and 10% by mass of silica particles having an average particle size of 0.1 μm with respect to the total resin. And an aqueous coating agent was diluted with; (weight ratio = 65/35) mixed solvent.

Comparative Example 6
In Example 2, a laminated polyester film having a coating thickness of 0.07 μm was obtained in the same manner as in Example 2 except that the coating liquid B was replaced with the coating liquid V. Table 1 shows the properties and evaluation results of the obtained single-layer film.

(Preparation of coating liquid W)
The polyester-based graft copolymer (a1) obtained above and the solid content of the ester-based polyurethane resin (trade name Takelac W5030, manufactured by Mitsui Takeda Chemical Co., Ltd.) having a glass transition point of 85 ° C. (catalog value) are polyester. System graft copolymer / polyurethane resin (mass ratio) = 80/20, and the isocyanate group content (regenerated NCO) is 5. with respect to 100 parts by mass of the total amount of the polyester system graft copolymer and polyurethane resin. The block isocyanate compound of 4% by mass is mixed so as to be 20 parts by mass, the total resin solid content concentration is 3.8% by mass, and the silica particles have an average particle diameter of 1.0 μm as the total resin. Water / isopropyl alcohol so as to contain 44% by mass and 10% by mass of silica particles having an average particle size of 0.1 μm with respect to the total resin. And an aqueous coating agent was diluted with; (weight ratio = 65/35) mixed solvent.

Comparative Example 7
In Example 2, a laminated polyester film having an easy-adhesion layer applied thickness of 0.07 μm was obtained in the same manner as in Example 2 except that the coating liquid B was replaced with the coating liquid W. Table 1 shows the properties and evaluation results of the obtained single-layer film.

Example 21
In the preparation of the coating liquid A, a coating liquid (Y) in which a melamine compound (Beccamin M-3 solid content concentration 60% manufactured by DIC) was changed to 16.7% by mass in the solid content instead of the blocked isocyanate compound was used. Except for the above, a laminated polyester film in which the coating thickness of the easy adhesion layer was 0.07 μm was obtained in the same manner as in Example 1. Table 1 shows the properties and evaluation results of the obtained single-layer film.

  The laminated polyester film for molding according to the present invention is excellent in adhesiveness, particularly adhesiveness under moisture and heat resistance, and therefore can be applied to a wide range of uses. Therefore, decorative molding materials such as building materials and mobile phone base materials, interior and exterior decoration materials for automobiles, home appliances such as TVs, refrigerators, washing machines, stereos and portable devices, and compacts for makeup Suitable as nameplates (including display plates and panels) used for mirror products such as mirrors, vehicles such as automobiles, ships, aircraft, buildings, play equipment (ski goggles, etc.), amusement devices, and other various mechanical devices It is. In particular, it is more suitable for uses under high-temperature and humid heat (bathrooms such as bathtubs, washstands, kitchens, sanitary, outdoor materials such as building materials, exteriors, solar panels, automobile interiors, and attics.

Claims (8)

A laminated polyester film having an easy-adhesion layer on at least one side of a base film made of a copolyester or a copolyester and a homopolyester,
The easy-adhesion layer includes a polyester-based graft copolymer and a polycarbonate-based polyurethane,
The polyester-based graft copolymer is obtained by grafting a polymerizable unsaturated monomer containing an acid anhydride having at least one double bond to a hydrophobic copolymerized polyester resin.
And the glass transition point (Tig) of an easily bonding layer is 30 to 55 degreeC,
Laminated polyester film for molding. The blending ratio of the polyester-based graft copolymer and the polycarbonate-based polyurethane in the easy-adhesion layer is polyester-based graft copolymer / polycarbonate-based polyurethane (mass ratio) = 80/20 to 30/70,
And the lamination polyester film for shaping | molding of Claim 1 containing 5-40 mass parts crosslinking agent with respect to 100 mass parts of total amounts of a polyester-type graft copolymer and a polycarbonate-type polyurethane.   The laminated polyester film for molding according to claim 1 or 2, wherein the crosslinking agent is a blocked isocyanate crosslinking agent.   The laminated polyester film for molding according to Claims 1 to 3, wherein the content of regenerated isocyanate groups in the blocked isocyanate crosslinking agent is 3.0 to 15.0% by mass.   The laminated polyester film for molding according to claim 1, wherein the haze is 1.0% or less.   The laminated polyester film for molding according to claim 1, wherein the easy adhesion layer has a thickness of 0.01 to 0.10 μm.   The molded object which laminated | stacked the printing layer on the easily bonding layer of the lamination | stacking polyester film for shaping | molding of Claims 1-6.   A molded body in which a printing layer, an adhesive layer, and an acrylic resin sheet are sequentially laminated on the easy adhesion layer of the laminated polyester film for molding according to claim 1 and a metal thin film layer is provided on the opposite surface.