JP2006233092A - Polyester-based resin composition, and thermally shrinkable film using the composition, thermally shrinkable label, and container having the label attached thereto - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a polyester-based resin composition suitably used for polyester-based thermally shrinkable films which exhibit good shrinkage characteristics, give good shrinkage finishes, when shrunk, have excellent heat resistance, and are little deteriorated with the passage of time, to provide a thermally shrinkable film, to provide a thermally shrinkable label, and to provide a container. <P>SOLUTION: This polyester-based resin composition comprises the following prescribed polyester-based resin (A) and the following prescribed polyester-based resin (B) in prescribed amounts, respectively. (A) The polyester-based resin comprising a dicarboxylic acid residue component containing a prescribed amount of an alicyclic dicarboxylic acid residue, and a diol residue component consisting mainly of ethylene glycol residue. (B) The polyester-based resin comprising a dicarboxylic acid residue component consisting mainly of an aromatic dicarboxylic acid residue except isophthalic acid residue and a diol residue component consisting mainly of a prescribed aliphatic diol residue and, if necessary, an alicyclic diol residue. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a polyester resin composition, a polyester heat shrinkable film composed of the composition, a heat shrinkable label, and a container provided with the label. More specifically, the present invention, when formed into a heat-shrinkable film, does not cause defects such as shrinkage spots, wrinkles, distortion, etc. after heat-shrinking processing, has good shrinkage finish, excellent heat resistance, and formed on the film The film can be easily cut and peeled along the perforated lines, and the elongation at break in the direction perpendicular to the main shrinkage direction of the heat-shrinkable film is large. Polyester resin composition suitably used for shrinkage labels and food packaging that can be processed at high speed with almost no breakage trouble of the shrinkable film, and a polyester heat shrinkable film composed of the composition, heat The present invention relates to a shrinkable label and a container provided with the label.

  Conventionally, stretch films made of polyvinyl chloride or polystyrene have been mainly used as shrink labels used for glass bottles and polyethylene terephthalate bottles (PET bottles) and shrink films for food packaging. On the other hand, in recent years, a heat-shrinkable film using a polyester resin excellent in safety and hygiene and chemical resistance has been demanded, and the use of a stretched film made of a polyester resin is increasing.

  However, since the shrinkage rate of polyester-based heat-shrinkable films that are currently used increases rapidly as the temperature rises, when coated on PET PET bottles, wrinkles, etc. occur on the film, causing shrinkage finish defects. There was a problem such as.

  Further, in recent years, with the recycling of PET bottles, perforations are applied to heat-shrinkable labels, and good perforation of the perforations is an important physical property of heat-shrinkable labels. . However, currently used polyester heat-shrinkable films have problems such as poor perforation.

  In addition, the film easily breaks in the direction perpendicular to the main film shrinkage direction during film formation (the flow direction in the heat shrinkable film production / processing process), and the film breaks in the printing process, the tubing process, or the labeling process. There was a problem such as. Furthermore, when the container etc. which carried out the film | membrane shrinking | contraction of the film received the impact etc. from the outside, there existed problems, such as a film fracture | rupture.

  The breaking phenomenon tends to become more prominent as the elapsed time and the storage time after film production become longer, particularly as the storage environment temperature becomes higher. In recent years, from the viewpoint of economy, there is an increasing demand for thinning and high-speed processing of heat-shrinkable films, and the improvement in rupture resistance to make the above-mentioned breakage difficult is important in polyester-based heat-shrinkable films. It has become a challenge.

  For the above various problems, by blending 5% by mass to 10% by mass of an aromatic polycarbonate resin with a polyethylene terephthalate polymer having a glass transition temperature (Tg) of 40 ° C. or higher and 80 ° C. or lower, A method of slowing heat shrinkage and extending the range of shrinkage temperature has been proposed (see, for example, Patent Document 1). Furthermore, a method of mixing 1 part by mass or more and 50 parts by mass or less of a resin having a glass transition temperature (Tg) of 20 ° C. or more with respect to 100 parts by mass of a polyester resin having a glass transition temperature (Tg) of 40 ° C. or more (for example, Patent Documents) 2) has been proposed. Further, the polyester resin is about 50% by weight or more and about 99% by weight or less, and is essentially a linear random aliphatic-aromatic copolyester or branched and / or chain extended copolyester of about 1% by weight to about 50% by weight. A method using the following has been proposed (see, for example, Patent Document 3).

  Further, a method of molding a composition comprising a polybutylene terephthalate copolymer and a polyethylene terephthalate copolymer obtained by copolymerizing a specific modified species so as to obtain a good appearance without going through a preheating step (for example, Patent Document 4). And a method of blending and molding a polybutylene terephthalate-modified product and a polyethylene terephthalate-modified product (see, for example, Patent Document 5) in order to obtain good shrinkability in the high-temperature shrinkage process.

  Further, the number of test pieces having a breaking elongation of 5% or less when stored in a 30 ° C. and 85% relative humidity environment for 2 weeks and performing a tensile test under specific conditions is 10% or less of the total number of test pieces. A polyester-based heat-shrinkable film excellent in fracture resistance in a direction perpendicular to the main shrinkage direction of the film has been proposed (see, for example, Patent Document 6).

Japanese Patent Laid-Open No. 5-25294 JP-A-4-50238 Special table 2004-536192 gazette JP 2001-151908 A JP 2002-212405 A JP 2003-41028 A

  However, each of the heat-shrinkable films described in Patent Documents 1 to 3 has a problem that the shrinkage finish is still insufficient and the cut performance of the perforated label is inferior. Further, the heat-shrinkable films described in Patent Document 4 and Patent Document 5 have problems that the shrinkage finish is still insufficient and the brittleness after stretching is inferior. Furthermore, the film described in Patent Document 6 is only limited in the rate at which a test piece having a very small breaking elongation occurs after a storage test, and the breaking elongation of a test piece having a breaking elongation of 5% or more. No mention is made of the size, and it cannot be said that the tear resistance is necessarily excellent. Therefore, this film has not been able to sufficiently cope with the problem of deterioration in brittleness over time such as film breakage in the various situations described above.

  The present invention has been made in order to solve the above-described problems of the prior art, and the object of the present invention is that when formed into a heat-shrinkable film, the film has a good shrinkage finish, and the brittleness deterioration with time. It is composed of a polyester-based heat-shrinkable film that is excellent in heat resistance and rupture resistance, and that can be easily cut and peeled along perforations formed in the film, and the composition. A polyester heat-shrinkable film, a heat-shrinkable label, and a container equipped with the label are provided.

  As a result of intensive studies to solve the above-mentioned problems, the present inventors have found that a copolyester resin (A) containing a predetermined amount of an alicyclic dicarboxylic acid component and an aromatic dicarboxylic acid component other than the isophthalic acid component And a polyester-based heat formed by molding a resin composition containing a polyester resin (B) composed of a predetermined aliphatic diol component and / or a diol component mainly composed of an alicyclic diol component. The present inventors have found that a shrinkable film can solve the above-mentioned problems and have completed the present invention.

That is, the subject of this invention is the following polyester resin (A) and the following polyester resin (B), 100 mass parts of polyester resin (B) with respect to 100 mass parts of polyester resin (A). More than 1900 mass parts or less, The polyester-type resin composition characterized by the above-mentioned.
(A) a dicarboxylic acid residue component containing an alicyclic dicarboxylic acid residue and a diol residue component mainly composed of an ethylene glycol residue, wherein the alicyclic dicarboxylic acid residue A polyester resin containing 5 mol% or more and 50 mol% or less of the base component.
(B) a dicarboxylic acid residue component mainly composed of an aromatic dicarboxylic acid residue other than an isophthalic acid residue, an aliphatic diol residue having 2 to 12 carbon atoms, or an aliphatic group having 2 to 12 carbon atoms A polyester resin comprising a diol residue component mainly composed of a diol residue and an alicyclic diol residue.

(2) The polyester resin composition according to (1), wherein the polyester resin (A) is a polyester resin not containing an isophthalic acid residue component.
(3) The polyester-type resin composition as described in (1) or (2) whose glass transition temperature of the said polyester-type resin (A) is 60 degreeC or more and 80 degrees C or less.

(4) The polyester resin composition according to any one of (1) to (3), wherein the alicyclic dicarboxylic acid residue is a 1,4-cyclohexanedicarboxylic acid residue.
(5) The polyester resin composition according to any one of (1) to (4), wherein the alicyclic diol residue is a 1,4-cyclohexanedimethanol residue.
(6) Heat in the main shrinkage direction when the polyester-based resin composition according to any one of (1) to (5) is formed, and is stretched at least in a uniaxial direction and immersed in water at 80 ° C. for 10 seconds. A polyester heat-shrinkable film having a shrinkage rate of 20% or more.

(7) A polyester heat-shrinkable multilayer film having at least one layer of the polyester heat-shrinkable film according to (6).
(8) A heat-shrinkable label using the polyester-based heat-shrinkable film according to (6) or the polyester-based heat-shrinkable multilayer film according to (7).
(9) A container equipped with the heat-shrinkable label according to (8).

  Since the polyester-based resin composition of the present invention contains at least two kinds of predetermined polyester-based resins, when it is formed into a heat-shrinkable film, it can impart good shrinkage characteristics to the film. Therefore, according to the present invention, the shrink finish is good, the heat resistance and the rupture resistance are excellent, and after heat shrink processing, the film can be easily cut along a perforation formed in advance and the film can be easily peeled off. A heat shrinkable film can be provided. In addition, according to the present invention, it is possible to provide a heat-shrinkable label having both good shrinkage characteristics, perforation cutability, heat resistance, and breakage resistance, and a container provided with the label.

  Hereinafter, the polyester resin composition of the present invention (hereinafter also referred to as “the composition of the present invention”), a polyester heat shrinkable film comprising the composition (hereinafter also referred to as “the film of the present invention”), and a heat shrinkable label. (Hereinafter also referred to as “label of the present invention”) and a container equipped with the label (hereinafter also referred to as “container of the present invention”) will be described.

[Polyester resin composition]
In the composition of the present invention, the polyester resin (A) and the polyester resin (B) below are 100 parts by mass of the polyester resin (B) with respect to 100 parts by mass of the polyester resin (A). It is a composition containing 1900 parts by mass or less.
(A) a dicarboxylic acid residue component containing an alicyclic dicarboxylic acid residue and a diol residue component mainly composed of an ethylene glycol residue, wherein the alicyclic dicarboxylic acid residue A polyester resin containing 5 mol% or more and 50 mol% or less of the base component.
(B) a dicarboxylic acid residue component whose main component is an aromatic dicarboxylic acid residue other than an isophthalic acid residue, and a diol residue component whose main component is an aliphatic diol residue having 2 to 12 carbon atoms, or A polyester resin comprising a diol residue component mainly composed of an aliphatic diol residue having 2 to 12 carbon atoms and an alicyclic diol residue.

  In the present specification, the “main component” refers to a component having a content ratio of 50 mol% or more. Specifically, the “based on ethylene glycol residue” in the polyester-based resin (A) means that the content ratio of ethylene glycol residue is 50 when all diol residue components are 100 mol%. It means that it is at least mol%. Furthermore, “the main component is an aromatic dicarboxylic acid residue other than isophthalic acid” in the polyester-based resin (B) means that an aromatic other than isophthalic acid is used when the total dicarboxylic acid residue component is 100 mol%. The content ratio of the group dicarboxylic acid residue is 50 mol% or more. In the polyester-based resin (B), “mainly an aliphatic diol residue having 2 to 12 carbon atoms” means 2 to 12 carbon atoms when the total diol residues are 100 mol%. The content ratio of the following aliphatic diol residues means 50 mol% or more. Furthermore, “having an aliphatic diol residue having 2 to 12 carbon atoms and an alicyclic diol residue as main components” in the polyester-based resin (B) means that all diol residue components are 100 mol%. The content ratio of the aliphatic diol residue having 2 to 12 carbon atoms and the alicyclic diol residue is 50 mol% or more.

<Polyester resin (A)>
The polyester resin (A) is composed of a dicarboxylic acid residue component containing an alicyclic dicarboxylic acid residue and a diol residue component mainly composed of an ethylene glycol residue.

  The alicyclic dicarboxylic acid residue contained in the dicarboxylic acid residue component of the polyester resin (A) is not particularly limited. For example, 1,2-dichlorohexanedicarboxylic acid, 1,3-cyclohexanedicarboxylic acid, 1,4 Mention may be made of residues derived from cyclohexanedicarboxylic acids or their ester derivatives. Cyclohexanedicarboxylic acid has a cis configuration and a trans configuration, but may have any configuration from cis isomer 100% to trans isomer 100%, and all combinations of cis isomer and trans isomer are possible. included. Among these, from the viewpoint of heat shrinkability and heat resistance, it is preferable that the trans isomer is a 1,4-cyclohexanedicarboxylic acid residue or an ester derivative residue thereof that is 20% or more and 100% or less.

  The dicarboxylic acid residue component other than the alicyclic dicarboxylic acid residue contained in the dicarboxylic acid residue component of the polyester resin (A) is preferably an aromatic dicarboxylic acid residue, and an isophthalic acid residue. An aromatic dicarboxylic acid residue other than is particularly preferred. By using a polyester-based resin containing an aromatic dicarboxylic acid residue other than isophthalic acid residues, when formed into a heat-shrinkable film, the film is prevented from brittle deterioration with time and imparts rupture resistance to the film. be able to. Examples of the aromatic dicarboxylic acid residue include terephthalic acid, orthophthalic acid, phenylenedioxydiacetic acid, 4,4′-diphenyldicarboxylic acid, 4,4′-diphenoxyethanedicarboxylic acid, and 4,4′-diphenylether. Residues derived from dicarboxylic acid, 4,4′-diphenylsulfone dicarboxylic acid, 1,5-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, or ester derivatives thereof can be exemplified, among which terephthalic acid residue Or the ester derivative residue is especially preferable.

  The alicyclic dicarboxylic acid residue is an alicyclic ring that can induce an alicyclic dicarboxylic acid residue in the dicarboxylic acid compound when the dicarboxylic acid compound and the diol compound are reacted to obtain the polyester resin (A). By mixing the formula dicarboxylic acid compound, it can be contained as a single copolymer component.

  The content of the alicyclic dicarboxylic acid residue is 5 mol% or more in the total dicarboxylic acid residue component (100 mol%), and the upper limit is 50 mol%, preferably 40 mol%, more preferably 25 mol. %. If the upper limit of the content rate of an alicyclic dicarboxylic acid residue is 50 mol%, the haze and heat resistance of the heat-shrinkable film obtained can be made compatible. If the lower limit of the content of the alicyclic dicarboxylic acid residue is 5 mol%, good shrinkage characteristics of the resulting heat-shrinkable film can be obtained.

  Furthermore, the polyester-based resin (A) may be obtained by copolymerizing a dicarboxylic acid residue other than the dicarboxylic acid residue component as long as the effects of the present invention are not impaired. Examples of such dicarboxylic acid residues include residues derived from aliphatic dicarboxylic acids such as malonic acid, succinic acid, adipic acid, azelaic acid, and sebacic acid, or ester derivatives thereof, trimellitic acid, and trimesin. A trifunctional or higher polyfunctional carboxylic acid residue derived from an acid, pyromellitic acid or the like or an ester derivative residue thereof can be exemplified.

  As a diol residue contained in the diol residue of the polyester resin (A), it is preferable to use an ethylene glycol residue as a main component from the viewpoint of shrinkage finish. The content of ethylene glycol residues is 50 mol% or more, preferably 60 mol% or more, and more preferably 70 mol% or more in all diol residue components (100 mol%). If the content rate of an ethylene glycol component is 50 mol% or more, a favorable shrinkage finish can be maintained.

  Furthermore, the diol residue component of the polyester resin (A) is, for example, 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,4-butanediol, 1,5-pentane. Diol, 1,6-hexanediol, 1,10-decanediol, 2,2-dimethyl-1,3-propanediol, diethylene glycol, 1,1-cyclohexanedimethanol, 1,2-cyclohexanedimethanol, 1,3 -Various diol residue components derived from cyclohexanedimethanol, 1,4-cyclohexanedimethanol, 1,2-cyclohexanediol, 1,4-cyclohexanediol and the like may be copolymerized. A butanediol residue or a 1,4-butanediol residue is preferred.

  The polyester resin (A) may be, for example, 4,4′-dihydroxybiphenyl, 2,2-bis (4′-hydroxyphenyl) propane, 2,2-, as long as the effects of the present invention are not impaired. Aromatic diols such as bis (4′-β-hydroxyethoxyphenyl) propane, bis (4-hydroxyphenyl) sulfone, bis (4-β-hydroxyethoxyphenyl) sulfone, glycolic acid, p-hydroxybenzoic acid, p- Monofunctional residue components derived from hydroxycarboxylic acids such as β-hydroxyethoxybenzoic acid, alkoxycarboxylic acids, stearic acid, stearyl alcohol, benzyl alcohol, benzoic acid, t-butylbenzoic acid, benzoylbenzoic acid, and the like, tricarbaryl Acid, hexanetricarboxylic acid, trimellitic acid, trimesic acid, Derived from melittic acid, benzophenonetetracarboxylic acid, naphthalenetetracarboxylic acid, 1,2,6-hexanetriol, gallic acid, trimethylolethane, trimethylolpropane, glycerol, pentaerythritol, sorbitol, dipentaerythritol, polyglycerol, etc. It is also possible to copolymerize trifunctional or higher polyfunctional residue components.

  From the viewpoint of imparting heat resistance to the resulting heat-shrinkable film, the polyester resin (A) preferably has a glass transition temperature (Tg) measured by a differential scanning calorimeter (DSC) of 60 ° C. or higher. . On the other hand, the upper limit is not particularly limited, but Tg is desirably 80 ° C. or less from the viewpoint of ease of molding. The glass transition temperature (Tg) of the polyester-based resin (A) is obtained by melting the polyester-based resin (A) at 280 ° C. for 5 minutes, then immersing it in liquid nitrogen and quenching it, and using it as a sample, It can be measured using DSC at a temperature rising rate of 20 ° C./min.

<Polyester resin (B)>
The polyester resin (B) constituting the composition of the present invention mainly comprises a dicarboxylic acid component having an aromatic dicarboxylic acid component other than the isophthalic acid residue as a main component and an aliphatic diol component having 2 to 12 carbon atoms. It consists of a diol residue component as a component, or a diol residue component mainly composed of an aliphatic diol residue having 2 to 12 carbon atoms and an alicyclic diol residue.
The dicarboxylic acid residue component constituting the polyester resin (B) has an aromatic dicarboxylic acid residue other than the isophthalic acid residue as a main component. By using an aromatic dicarboxylic acid residue component other than the isophthalic acid residue component as a main component, when formed into a heat-shrinkable film, it effectively suppresses the embrittlement of the film over time and is resistant to breakage to the film. Sex can be imparted.

  Examples of the aromatic dicarboxylic acid residue include terephthalic acid, orthophthalic acid, phenylenedioxydiacetic acid, 4,4′-diphenyldicarboxylic acid, 4,4′-diphenoxyethanedicarboxylic acid, and 4,4′-diphenylether dicarboxylic acid. , 4,4′-diphenylsulfone dicarboxylic acid, 1,5-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, or residues derived from ester derivatives thereof. Ester derivative residues are preferred.

  The content of the aromatic dicarboxylic acid residue is 50 mol% or more, preferably 70 mol% or more, more preferably 80 mol% or more, and most preferably 90 mol% in all dicarboxylic acid residue components. % Or more. Moreover, there is no restriction | limiting in particular in the upper limit of the said content rate, What is necessary is just 100 mol% or less. If the content rate of an aromatic dicarboxylic acid residue is 50 mol% or more, favorable heat resistance can be provided to the heat-shrinkable film obtained.

  The dicarboxylic acid residue component constituting the polyester resin (B) can be copolymerized with a dicarboxylic acid residue component other than the aromatic dicarboxylic acid residue component as long as the effects of the invention are not impaired. . Examples of such dicarboxylic acid residues include residues derived from aliphatic dicarboxylic acids such as malonic acid, succinic acid, adipic acid, azelaic acid, and sebacic acid, or ester derivatives thereof, trimellitic acid, trimesic acid, and pyromellitic acid. A trifunctional or higher polyfunctional carboxylic acid residue derived from an acid or the like or an ester derivative residue thereof can be exemplified.

  The diol residue component constituting the polyester resin (B) is an aliphatic diol residue having 2 to 12 carbon atoms, or an aliphatic diol residue and an alicyclic diol residue having 2 to 12 carbon atoms. The main component. Examples of the diol residue include ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,4-butanediol, 1,5-pentanediol, 1,6 -Aliphatic diol residues derived from hexanediol, 1,10-decanediol, 2,2-dimethyl-1,3-propanediol, diethylene glycol, etc., 1,1-cyclohexanedimethanol, 1,2-cyclohexane Examples include alicyclic diol residues derived from dimethanol, 1,3-cyclohexanedimethanol, 1,4-cyclohexanedimethanol, 1,2-cyclohexanediol, 1,4-cyclohexanediol, and the like. Among them, it is preferable that the diol residue component contains ethylene glycol residue and 1,4-cyclohexanedimethanol residue as main components. Cyclohexanedimethanol has a cis and trans steric configuration, but may be in any range between 100% cis isomer and 100% trans isomer, and all combinations in between. included. Of these, from the viewpoint of heat shrinkability, 1,4-cyclohexanedimethanol having a trans isomer of 20% to 100% is preferable.

  The content of the aliphatic diol residue having 2 to 12 carbon atoms or the total content of the aliphatic diol residue having 2 to 12 carbon atoms and the alicyclic diol residue contained in the diol residue component is , 50 mol% or more, preferably 60 mol% or more, and more preferably 70 mol% or more with respect to the total diol residue component (100 mol%). If the content of the aliphatic diol residue having 2 to 12 carbon atoms and the total content of the aliphatic diol residue having 2 to 12 carbon atoms and the alicyclic diol residue are 50 mol% or more , Good shrinkage finish can be maintained. The content of the alicyclic diol residue with respect to all diol residue components is 3 mol% or more, preferably 8 mol% or more, and less than 50 mol%, preferably 40 mol% or less.

  The polyester resin (B) may further contain a polyether residue component. The kind of the polyether residue component is not particularly limited, but a polyalkylene glycol residue is preferred from the viewpoint of shrink finish in the heat shrinkable film. Examples of polyalkylene glycol residues include polyethylene glycol, polypropylene glycol, polytrimethylene glycol, polytetramethylene glycol, polyhexamethylene glycol, polyalkylene glycol residues derived from ethylene oxide and propylene oxide blocks or random copolymers. A group can be exemplified. Among these, polyethylene glycol residues and polytetramethylene glycol residues are preferable, and from the viewpoint of increasing the degree of polymerization in the polyester resin (B) and improving the shrink finish of the resulting polyester heat shrinkable film, A tetramethylene glycol residue is particularly preferred. The polyether residue component may be copolymerized alone or in combination of two or more.

  When the polyether residue component contains a polyalkylene glycol residue, the number average molecular weight of the polyalkylene glycol from which the polyalkylene glycol residue can be derived is 500 or more, preferably 600 or more, and 6,000 or less, preferably Is desirably 4,000 or less, more preferably 3,000 or less. If the number average molecular weight of the polyalkylene glycol is 500 or more, the tensile elasticity modulus of the resulting polyester heat-shrinkable film does not become too high. On the other hand, if the upper limit is 6,000, the resulting polyester heat The transparency of the shrinkable film becomes good.

  In addition, the polyalkylene glycol may be used in combination of plural kinds having different number average molecular weights. When a plurality of types are used in combination, the number average molecular weight in a uniformly mixed state is preferably within the above range. The number average molecular weight of the polyalkylene glycol can be measured by a general method such as gel permeation chromatography.

  When the polyester-based resin (B) contains the polyalkylene glycol residue component, the content of the polyalkylene glycol residue is 0.5 mol% or more, preferably 1 mol% or more in the total diol residue components. And less than 5 mol%, preferably less than 3 mol%. When the content of the polyalkylene glycol is less than 5 mol%, an extreme decrease in the glass transition temperature of the polyester-based resin (B) can be suppressed, and elongation deterioration with time can also be suppressed.

  Further, the polyester-based resin (B) is within a range not impairing the effects of the present invention, and for example, 4,4′-dihydroxybiphenyl, 2,2-bis (4′-hydroxyphenyl) propane, 2,2- Aromatic diols such as bis (4′-β-hydroxyethoxyphenyl) propane, bis (4-hydroxyphenyl) sulfone, bis (4-β-hydroxyethoxyphenyl) sulfone, glycolic acid, p-hydroxybenzoic acid, p- Monofunctional residue components derived from hydroxycarboxylic acids such as β-hydroxyethoxybenzoic acid and alkoxycarboxylic acids, stearic acid, stearyl alcohol, benzyl alcohol, benzoic acid, t-butylbenzoic acid, benzoylbenzoic acid, and the like, tricarbaryl Acid, hexanetricarboxylic acid, trimellitic acid, trimesic acid, Derived from romellitic acid, benzophenone tetracarboxylic acid, naphthalene tetracarboxylic acid, 1,2,6-hexanetriol, gallic acid, trimethylolethane, trimethylolpropane, glycerol, pentaerythritol, sorbitol, dipentaerythritol, polyglycerol, etc. It is also possible to copolymerize trifunctional or higher polyfunctional residue components.

  The polyester resins (A) and (B) are dissolved in a mixed solvent of phenol / 1,1,2,2-tetrachloroethane (mass ratio 1: 1), and the intrinsic viscosity measured at 30 ° C. is usually 0. 0.4 dl / g or more, preferably 0.6 dl / g or more, more preferably 0.7 dl / g or more, 1.5 dl / g or less, preferably 1.2 dl / g or less, more preferably 1.1 dl / g. It is preferable that it is the range below g. If the intrinsic viscosity is 0.4 dl / g or more, sufficient mechanical properties can be obtained, and if it is 1.5 dl / g or less, molding is easy when molding a molded product.

  The polyester resins (A) and (B) constituting the composition of the present invention are produced by a conventional production method of polyester resins, that is, by a batch polymerization method or a continuous method by a direct polymerization method or a transesterification method. Can do. Here, the aforementioned arbitrary copolymer component can be added at any stage of the polycondensation reaction process. Further, an oligomer having a low degree of polymerization is produced from a dicarboxylic acid compound and a diol compound, and this is copolycondensed with any of the aforementioned copolymer components to produce polyester resins (A) and (B). You can also.

  The resin obtained by the polycondensation reaction is usually extracted in a strand form from an outlet provided at the bottom of the polycondensation reaction tank, and is cooled with water or after water cooling and then cut into a pellet. Furthermore, by subjecting the pellets after polycondensation to heat treatment and solid phase polycondensation, the degree of polymerization can be further increased, and reaction by-products such as acetaldehyde and low-molecular oligomers can be reduced.

  In the production method, the esterification reaction is performed using an esterification reaction catalyst such as antimony trioxide, an organic acid salt such as antimony, titanium, magnesium, calcium, or an organic metal compound, if necessary. The transesterification reaction can be carried out using a transesterification reaction catalyst such as an organic acid salt or an organic metal compound such as lithium, sodium, potassium, magnesium, calcium, manganese, titanium, or zinc, if necessary. It can be carried out.

  The polycondensation reaction is performed in the presence of phosphorus compounds such as orthophosphoric acid, phosphorous acid, hypophosphorous acid, polyphosphoric acid, and esters and organic acid salts thereof, and, for example, antimony trioxide, germanium dioxide, The reaction is carried out in the presence of a metal oxide such as germanium tetroxide, or a polycondensation catalyst such as an organic acid salt or organic metal compound such as antimony, germanium, zinc, titanium, or cobalt. Of these polycondensation catalysts, at least one selected from tetrabutoxy titanate, antimony trioxide, and germanium dioxide is preferably used. The catalyst amount is usually 5 mass ppm or more and 2000 mass ppm or less as a metal amount (atomic conversion amount) with respect to the theoretical yield of the obtained polyester-based resin for both the esterification reaction catalyst, the transesterification reaction catalyst, and the polycondensation catalyst. Preferably, it is used in the range of 10 ppm to 500 ppm by mass.

  The composition of the present invention may further contain inorganic and / or organic fine particles from the viewpoint of imparting blocking resistance and slipperiness when formed into a heat-shrinkable film. The content of the fine particles is 0.005% by mass or more, preferably 0.01% by mass or more, more preferably 0.02% by mass or more, and 1% by mass or less, based on the mass of the entire composition. Preferably it is 0.6 mass% or less, More preferably, it is desirable that it is the range of 0.5 mass% or less.

  Examples of the inorganic fine particles include silica, alumina, titania, kaolin, clay, calcium carbonate, calcium phosphate, lithium fluoride, carbon black, and catalysts such as alkali metals, alkaline earth metals, and phosphorus compounds at the time of polyester polymerization. The resulting precipitates can be mentioned. Examples of the organic fine particles include various crosslinked polymers.

The average particle size of the organic or inorganic fine particles is 0.001 μm or more, preferably 0.005 μm or more, more preferably 0.01 μm or more, from the viewpoint of obtaining the above-described effects of blocking resistance and easy slipping. It is desirable that the thickness be in the range of 6 μm or less, preferably 4 μm or less, more preferably 3 μm or less.
The “average particle size” as used herein means a 50% volume average particle size (d50) measured by a method such as a laser diffraction method, an electromagnetic wave scattering method such as a dynamic light scattering method, or a light transmission method such as a centrifugal sedimentation method. ), But if there is a difference depending on the measurement method, use the value determined by the laser diffraction method.

  The mixing method of the organic or inorganic fine particles is not particularly limited, and can be added during the polymerization process of the polyester resin, or can be mixed during the production process of the polyester resin composition or the molding process of the polyester heat shrinkable film. You can also

  The composition of this invention may contain other resin in the range which does not impair the effect of this invention. Examples of the other resin include polyethylene resins, polypropylene, modified maleic anhydrides thereof, polyolefin resins such as ionomers, thermoplastic resins such as polyamide resins and polystyrene resins, and thermoplastic elastomers.

  Furthermore, the composition of the present invention is an antioxidant such as phenolic, phosphorus, thioether, benzotriazole, benzophenone, benzoate, hindered amine, cyanoacrylate, etc., as long as the effects of the present invention are not impaired. Light stabilizers, inorganic or organic crystal nucleating agents, molecular weight modifiers, hydrolysis resistance, antistatic agents, lubricants, mold release agents, plasticizers, flame retardants, flame retardant aids, foaming agents, coloring It may contain additives such as additives and dispersion aids, and reinforcing materials such as glass fiber, carbon fiber, mica and potassium titanate fiber.

  The composition of the present invention is obtained by mixing the polyester resin (A) and the polyester resin (B) simultaneously or sequentially. The mixing amount of the polyester resin (A) and the polyester resin (B) is 100 parts by mass or more, preferably 200 parts by mass or more of the polyester resin (B) with respect to 100 parts by mass of the polyester resin (A). More preferably, it is 400 parts by mass or more, and the upper limit is 1900 parts by mass, preferably 1500 parts by mass, and more preferably 1000 parts by mass. When the blending amount of both polyester resins is within the above range, a good shrink finish can be imparted to the heat shrinkable film when it is formed into a heat shrinkable film. In addition, the conditions used by the manufacturing method of the conventional polyester-type resin composition can be applied to conditions, such as temperature at the time of mixing of the said polyester-type resin (A) and (B), a pressure.

[Polyester heat shrinkable film]
The film of the present invention is a film formed from a composition containing the polyester-based resin (A) and the polyester-based resin (B), and the main film when immersed in warm water at 80 ° C. for 10 seconds. The thermal contraction rate in the shrinking direction is 20% or more, preferably 30% or more, and more preferably 40% or more. Since the film of the present invention has an appropriate shrinkage ratio of 20% or more in the film main shrinkage direction in 80 ° C. warm water, which is a relatively high temperature, the film of the present invention is attached to an ordinary container to shrink and coat. be able to. The heat shrinkage rate of the film of the present invention can be adjusted by increasing or decreasing the content of the alicyclic dicarboxylic acid residue component contained in the polyester resin (A) of the composition of the present invention. For example, the thermal contraction rate of the film can be increased by increasing the content of the alicyclic dicarboxylic acid residue component contained in the polyester resin (A).
In the present specification, the “main shrinkage direction” means a direction having a large thermal shrinkage rate in the longitudinal direction (longitudinal direction) and the transverse direction (width direction). The direction corresponding to the direction is meant, and the “orthogonal direction” means a direction perpendicular to the main contraction direction.

  The film of the present invention has an average shrinkage of 5% or less, preferably 4% or less, more preferably 3% or less when immersed in warm water at 70 ° C. to 90 ° C. for 10 seconds. It is desirable. If the average shrinkage in the direction perpendicular to the film is 5% or less in the above temperature range, the film of the present invention can suppress the occurrence of sink marks in the label vertical direction during label molding, particularly from 70 ° C to 90 ° C. Generation of shrinkage spots and wrinkles can be suppressed in the temperature range, and shrinkage characteristics and commercial value can be improved.

  The natural shrinkage ratio in the main shrinkage direction and the orthogonal direction of the film of the present invention is, for example, 2.0% or less, preferably 1.0% or less, more preferably 0.5% or less after 30 days storage at 30 ° C. is there. When the natural shrinkage rate under the above conditions is 2.0% or less, the film of the present invention can be stably attached to a container or the like even when stored for a long period of time, and hardly causes problems in practice.

The film of the present invention has a tensile modulus in the main shrink direction (TD) of 2,500 MPa or more, preferably 3,000 MPa or more, more preferably 3,500 Mpa or more, and the upper limit is 7,000 MPa, preferably 6,000 MPa. More preferably, it is 5,500 MPa. Further, the tensile modulus of elasticity of the film of the present invention in the direction perpendicular to the main shrinkage direction (MD) is 1,000 MPa or more, preferably 1,300 MPa or more, more preferably 1,500 MPa or more, and the upper limit is 3,500 MPa, preferably 3,000 MPa, more preferably 2,500 MPa. For the tensile modulus, specimens having a width of 5 mm and a length of 70 mm were taken in the orthogonal direction (MD) and the main contraction direction (TD), respectively, and the specimens were placed in a temperature-controlled room at 23 ° C. and 50 RH% with a chuck spacing of 50 mm. After setting in the tensile tester, the stress-strain curve is obtained at a tensile test speed of 5 mm / min, and the tensile modulus can be obtained from the following formula (1) in the straight line portion immediately after the start of the test.
Tensile modulus = Stress difference due to the original average cross-sectional area between two points on a straight line / Strain difference between the same two points ... (1)

  The film of the present invention has a right angle tear strength measured in accordance with JIS K7128-3 of 100 N / mm or more, preferably 150 N / mm or more, more preferably 200 N / mm or more in the orthogonal direction (MD). The shrinkage direction (TD) is 200 N / mm or more, preferably 300 N / mm or more, and more preferably 350 N / mm or more.

  The rupture resistance of the film of the present invention is evaluated by tensile elongation, and in a tensile test under a 0 ° C. environment, the elongation is 100% or more, preferably 200% or more in the orthogonal direction (MD) of the film, particularly for label applications. More preferably, it is 300% or more.

  For example, when the film of the present invention has a thickness of 50 μm measured according to JIS K7105, the haze value is preferably 10% or less, more preferably 7% or less, and 5%. More preferably, it is as follows. If the haze value is 10% or less, the transparency of the film can be obtained and a display effect can be obtained.

  The thickness of the film of the present invention is 10 μm or more, preferably 20 μm or more, and is 100 μm or less, preferably 80 μm or less. If the thickness of the film is 10 μm or more, there is an advantage that secondary processing is easy, and if the thickness of the film is 100 μm or less, good workability of the film can be maintained.

  The heat resistance of the film of the present invention can be evaluated by the fusing temperature (fusing start temperature). In PET bottles for hot warmers and hot benders, the labels locally attached to the bottles may be exposed to high temperatures and fused to each other. In order to prevent this, the fusion start temperature of the film of the present invention is preferably 90 ° C. or higher, more preferably 120 ° C. or higher, and further preferably 140 ° C. or higher.

  The perforation of the film of the present invention is evaluated based on whether a heat-shrinkable film on which a perforation of a predetermined size is engraved is torn along the perforation and the cut is torn along the perforation. can do. The perforation of the perforation is the content of the alicyclic dicarboxylic acid residue in the polyester resin (A) and the content of the alicyclic diol residue in the polyester resin (B) containing the alicyclic diol residue. And by adjusting the blending amount of both resins. For example, the content (preferably 10 mol% or more) of the alicyclic dicarboxylic acid residue in the polyester tree (A) and the content (preferably 20) of the alicyclic diol residue in the polyester resin (B). Perforation of the perforation can be improved. For example, the perforation can be improved by adjusting the blending amount of the polyester resin (B) to be 2.3 times or more of the blending amount of the polyester resin (A).

  Here, the “perforation” means, for example, in the case of a heat-shrinkable film (or heat-shrinkable label), used from a container engraved in the orthogonal direction and / or main shrinkage direction and covered with the heat-shrinkable film. This refers to a group of perforated continuous small holes provided to facilitate the separation when the film is separated later.

The size and shape of the perforation are not particularly limited. For example, the perforation has a length of 0.05 to 2 mm, a width of 0.5 to 2 mm, a rectangular shape or a rectangular shape, or a diameter or a long axis length of about 0.05 to 2 mm. A circular or elliptical perforation may be mentioned, and a rectangular perforation of about 0.5 to 1 mm is preferable. The perforations can be formed by pressing a disk provided with a large number of needle-like protrusions. For example, by appropriately adjusting the shape and interval of the needle-like protrusions, perforations of various shapes are formed on the film at regular intervals. Can be formed.
The perforation evaluation method is, for example, forming the film of the present invention cut into a predetermined size into a cylindrical shape, covering the bottle, tearing it with a fingertip along the perforation after heat shrink processing, It can be evaluated by a method of visually confirming whether or not cutting has occurred in the middle of the eyes.

  The elongation change with time of the film of the present invention is 50% or more under the condition of 20 mm between chucks in a perpendicular direction (MD) and a pulling speed of 200 mm / min. It can be represented by the number that extends (ie, beyond the yield point). For example, after storage at 30 ° C. for 30 days, a test piece cut out at 15 mm in the main shrink direction (TD) of the film, 50 mm to 150 mm, preferably 50 mm to 100 mm, more preferably 100 mm in the orthogonal direction (MD), When the tensile test is performed under the conditions of a distance between chucks of 20 mm, 23 ° C., 50% RH, and a tensile speed of 200 mm / min, the number of stretches by 50% or more is 80% or more of all the test pieces in the case of the film of the present invention. It is preferably 90% or more, and most preferably 100%.

Next, although the manufacturing method of the film of this invention is demonstrated concretely, the manufacturing method of the film of this invention is not limited to this.
The film of this invention can be manufactured using a conventionally well-known manufacturing method, The manufacturing method is not specifically limited. For example, the polyester resins (A) and (B) as raw materials are melt-extruded in advance in a temperature range of 200 ° C. or more and 300 ° C. or less, cut into pellets, and then the pellet-like polyester resin composition is 200 A heat-shrinkable film can be produced by melt extrusion in a temperature range of from ℃ to 300 ℃. Moreover, a film can also be directly produced by melt-extruding the polyester resins (A) and (B) in a temperature range of 200 ° C. to 300 ° C. It does not specifically limit as an extrusion method, A T-die method, a tubular method, etc. can be used.

  When producing a uniaxially stretched film using the T-die method, after extrusion, the surface temperature is rapidly cooled on a casting drum having a temperature range of 15 ° C. to 80 ° C. to form an unstretched film having a thickness of 30 μm to 300 μm. To do. Next, using a heated longitudinal stretching roll, unstretched under conditions of a roll temperature of 60 ° C. or more and 120 ° C. or less, a draw ratio of 1.0 to 1.3 times, preferably 1.0 to 1.1 times. Stretch the film. Next, using a tenter, the film is stretched under conditions of a stretching temperature of 60 ° C. or higher and 120 ° C. or lower and a draw ratio of 1.7 times or higher and 7.0 times or lower, and then heat-treated at a temperature of 55 ° C. or higher and 100 ° C. or lower. .

  When a biaxially stretched film is produced using the T-die method, after extrusion, the surface temperature is rapidly cooled on a casting drum having a temperature range of 15 ° C. or higher and 80 ° C. or lower, and an unstretched film having a thickness of 40 μm or more and 900 μm or less. Form. Next, using a heated longitudinal stretching roll, unstretched under the conditions of a roll temperature of 60 ° C. or more and 120 ° C. or less, a stretching ratio of 1.7 times or more and 7.0 times or less, and preferably 2.5 times or more and 6.0 times or less. Stretch the film. Next, after stretching under the conditions of a stretching temperature of 60 ° C. or more and 120 ° C. or less, a stretching ratio of 1.7 times or more and 7.0 times or less, preferably 2.5 times or more and 6.0 times or less, using a tenter, It heats and winds up at the temperature of 55 to 100 degreeC.

[Polyester heat shrinkable multilayer film]
The film of the present invention can be formed into a multilayer film by laminating other layers made of heterogeneous materials or homogeneous materials. The multilayer film of the present invention may include at least one layer of the film of the present invention (single layer). For example, in addition to the film of the present invention, two or three layers or three or five layers composed of one or two different kinds of materials. It can be composed of a plurality of layers depending on the application, such as 4 types and 7 layers. Especially, 2 types 3 layers or 3 types 5 layers which used the film of this invention as an intermediate | middle layer are suitable. For example, the front and back layers are preferably layers made of a resin excellent in printing and sealing properties, and the film of the present invention is preferably used for the intermediate layer in order to impart shrinkage characteristics.

  The multilayer film of the present invention is preferably a resin with low crystallinity as the resin used for the front and back layers. For example, when a polyester resin is used, the diol residue contained in the diol residue component is 1,4-butanediol. And the content is 25 mol% or less in all diol residue components, and the content of 1,4-cyclohexadimethanol residue is 25 mol% or more in all diol residue components It is desirable to use

  The thickness ratio of the multilayer film of the present invention is, for example, in the case of two types and three layers, the thickness ratio in the range of front and back layers: intermediate layer: front and back layers = 1: 2: 1 to 1: 10: 1. it can. In the case of 3 types and 5 layers, [front / back layer: adhesive layer]: intermediate layer: [adhesive layer: front / back layer] = [1]: 2: [1] to [1]: 10: [1] thickness The thickness ratio of [front and back layers: adhesive layer] can be in the range of 1: 1 to 5: 1.

  In the multilayer film of the present invention, the thickness of the entire film can be appropriately selected depending on the application, and is usually in the range of 10 μm to 600 μm. For example, in the case of packaging applications such as foods, beverages, and pharmaceuticals, the total film thickness is in the range of 15 μm to 400 μm, preferably 15 μm to 200 μm. When used as a label for polyester bottles, glass bottles, and other plastic containers, the thickness is 20 μm or more and 100 μm or less, preferably 80 μm or less, more preferably 60 μm or less. Is preferred.

[Heat-shrink label and container equipped with the label]
The film of the present invention has excellent shrink finish, natural shrinkage, transparency, mechanical strength such as film stiffness (rigidity at room temperature), rupture resistance, etc., and its use is particularly limited. However, it is used for shrinkage labels for PET bottles (round and square bottles of about 300 milliliters to 2 liters), shrinkage packaging for various foods and articles, shrinkage wrapping packaging, cap seals for various containers, various foods and articles The shrinkable tube can be suitably used as a heat shrinkable label, and a container equipped with the shrinkable label can be obtained. And the heat-shrinkable label of this invention and the container equipped with this label can be produced using a conventionally well-known method.

  In addition to the heat-shrinkable label material of plastic molded products, the film of the present invention has a material that is extremely different from the heat-shrinkable film of the present invention in terms of coefficient of thermal expansion and water absorption, such as metal, porcelain, glass, paper, polyethylene, Heat of a container using at least one selected from polyolefin resins such as polypropylene and polybutene, polymethacrylate resins, polycarbonate resins, polyethylene resins such as polyethylene terephthalate and polybutylene terephthalate, and polyamide resins as a constituent material It can be suitably used as a shrinkable label material.

  Although the container which can utilize the film of this invention is not specifically limited, A plastic container can be used suitably. As a material constituting the plastic container, in addition to the above resins, polystyrene, rubber-modified impact-resistant polystyrene (HIPS), styrene-butyl acrylate copolymer, styrene-acrylonitrile copolymer, styrene-maleic anhydride copolymer , Acrylonitrile-butadiene-styrene copolymer (ABS), methacrylate-butadiene-styrene copolymer (MBS), polyvinyl chloride resin, phenol resin, urea resin, melamine resin, epoxy resin, unsaturated polyester resin, A silicone resin etc. can be mentioned. These plastic packages may be a mixture of two or more resins or a laminate.

  EXAMPLES Next, although an Example demonstrates this invention concretely, this invention is not restrict | limited at all by these Examples.

A. Measurement Method Composition Analysis of Polyester Resin Used in Each Example and Comparative Example, 1,4-Cyclohexanedicarboxylic Acid (hereinafter referred to as “CHDA”) cis / Trans Content, Intrinsic Viscosity, and Glass Transition Temperature The measurement of was performed by the following method.

(Composition analysis of polyester resin)
A solution obtained by dissolving various polyester resins in deuterated chloroform (solvent) (sample concentration: 100 mg / 1 ml solvent) was used as a sample, and this sample was analyzed by monitoring ¹ H with a nuclear magnetic resonance apparatus (NMR). With respect to the dicarboxylic acid residue, the mol% with respect to all the dicarboxylic acid residue components of the compound to be analyzed was determined, and with respect to the diol residue, the mol% with respect to all the diol residues of the compound to be analyzed was determined.

(Method for measuring CHDA cis / trans content)
In a 50 ml volumetric flask, 0.2 g of CHDA was dissolved in 1.2 ml of 4M (4N) sodium hydroxide. Subsequently, 40 ml of purified water was added to the obtained solution, and after adjusting to pH 5 with 200 μl of phosphoric acid, pure water was added to make 50 ml. This was measured under the following conditions using liquid chromatography, and the trans isomer and cis isomer content were determined from the peak areas derived from the trans isomer and cis isomer.
Measuring device: LC-10AD manufactured by Shimadzu Corporation
Column: J'share ODS-H80 4.6 mm x 250 mm
Measurement temperature: 50 ° C
Moving layer: Acrylonitrile / pure water / H ₃ PO ₄ = 200/800/4 (volume ratio)
Flow rate: 0.6ml / min
Detector: UV (210 nm)
Injection volume: 20 μl

(Measurement of intrinsic viscosity)
A polyester resin chip sample of 0.5 g was mixed with phenol / tetrachloroethane (mass ratio 1/1) as a solvent and dissolved at 110 ° C. for 30 minutes so that the concentration (c) was 1.0 g / dl. A solution was prepared. Using the Ubbelohde viscometer at 30 ° C., the relative viscosity (ηrel) with respect to the solvent alone (c = 0) was measured, and the relative viscosity (ηrel) -1 was defined as the specific viscosity (ηsp). The ratio (ηsp / c) to c) was determined. Similarly, the concentration (c) is 0.5 g / dl, 0.2 g / dl, and 0.1 g / dl, and the respective ratios (ηsp / c) are obtained. From these values, the concentration (c) is set to 0. The ratio (ηsp / c) when extrapolated was determined as intrinsic viscosity [η] (dl / g).

(Measurement of glass transition temperature)
About 10 mg of various polyester resins were melted at 280 ° C. for 5 minutes, then immersed in liquid nitrogen, quenched, and made amorphous to obtain a sample using a differential scanning calorimeter “DSC822e” manufactured by METTLER TOLEDO. The measurement was performed at a temperature rate of 20 ° C./min.

B. Measurement Method The polyester heat-shrinkable film produced in each example and comparative example was evaluated by the following method.

(Evaluation methods)
(1) Heat Shrinkage The polyester heat-shrinkable film obtained in each Example and Comparative Example was cut into a size of 70 mm in the main shrinkage direction and 10 mm in the direction perpendicular to the main shrinkage direction to prepare a sample. Marks with 50mm intervals in the direction of main contraction of the sample, dipped in a warm water bath at 80 ° C for 10 seconds, and then dipped in cold water at 23 ° C for 30 seconds to measure the marked line interval (A). The thermal contraction rate was calculated from (2).
Thermal contraction rate (%) = 100 × (50−A) / 50 (2)

(2) Shrinkage finish The polyester heat-shrinkable film obtained in each of the examples and comparative examples was made into a cylindrical shape so that the main shrinkage direction was the transverse direction, and then the cylindrical film was filled with water in a 350 ml PET bottle. The film was passed through a steam shrink tunnel adjusted in a temperature range of 80 ° C. to 90 ° C. for 5 seconds, and then the shrinkage state of the film was observed and judged according to the following criteria.
○: Appearance with a clear appearance without shrinkage unevenness and wrinkles Δ: Appearance with slight shrinkage unevenness and wrinkles ×: Appearance with significant shrinkage unevenness and wrinkles

(3) Perforation perforation Cut out from the polyester heat-shrinkable film obtained in each Example and Comparative Example to a size of 60 mm in the main shrinkage direction and 300 mm in a direction perpendicular to the main shrinkage, and cylindrical with a folding diameter of 105 mm The heat-shrinkable label was produced by processing. Next, one rectangular perforation was formed in the orthogonal direction on the heat-shrinkable label using a sewing blade having a blade size of 0.7 mm × 0.7 mm and a blade-to-blade spacing of 0.7 mm. Next, using a steam tunnel (“SKT-3000” manufactured by Keiyu System Co., Ltd.), a 350 ml PET bottle filled with water was coated with the heat-shrinkable label from the bottom to the neck. Thereafter, the bottle was refrigerated to 5 ° C., and the bottle immediately after taking out from the refrigerator was torn the perforation of the label with a fingertip, and at that time, it was visually observed whether or not cutting occurred in the middle of the perforation. . The number of measurements was set to 5 and the determination was made according to the following criteria.
○: When there are 3 or more cuts without any problem along the perforation or feeling resistance on the way to the bottom of the bottle △: Cut to some extent along the perforation, but peel the apple before reaching the bottom When there are 3 or more objects in the state ×: When there are 3 or more apples that are hardly cut along the perforation and peeled

(4) Elongation over time Polyester heat-shrinkable film left in a gear oven at 30 ° C. for 30 days is carefully cut out with a feather blade to a size of 15 mm in the main shrinkage direction and 50 mm in the orthogonal direction, and TM-20 manufactured by Intesco 10 were measured in the orthogonal direction at an interval of 20 mm between the chucks and a tensile speed of 200 mm / min, and the number extending 50% or more was measured. Of all the samples, the number that extends by 50% or more is 9 or more and 10 or less, ◎, 7 or more and 8 or less, ◯, 5 or more and 6 or less, △, 4 or less Some were represented as x.

(5) Fusion start temperature The polyester-based heat-shrinkable film obtained in each of the examples and comparative examples was cut into a size of 60 mm in the main shrink direction and 300 mm in a direction perpendicular to the main shrink direction, and the two films were stacked. The fusion start temperature was measured with a “TP-701-A heat seal tester” manufactured by Tester Sangyo Co., Ltd. The temperature is set in the range of 70 ° C to 170 ° C at intervals of 5 ° C, and after pressurizing at each temperature at a pressure of 0.1 MPa x 1 minute, the presence or absence of fusion is confirmed, and the fusion is the lowest temperature at which fusion occurs. When the deposition start temperature was less than 90 ° C., ×, 90 ° C. or more and less than 120 ° C., Δ, 120 ° C. or more and less than 140 ° C., and 140 ° C. or more.

C. Production of raw material polyester resin (1) Polyester resin 1 (PET1)
Polyester resin 1 was produced by the method of Production Example 1 described below. As a result of analyzing the composition of the polyester resin 1 by the above method, 10 mol% of the dicarboxylic acid residue components are CHDA residues, 90 mol% is terephthalic acid (hereinafter abbreviated as “TPA”), and diol. Of the residue components, 98 mol% was an ethylene glycol (hereinafter abbreviated as “EG”) residue, and 2 mol% was a diethylene glycol (hereinafter abbreviated as “DEG”) residue. Moreover, it was 0.84 dl / g as a result of measuring the intrinsic viscosity of the polyester-type resin 1 by the said method.

<Production Example 1>
Using a batch polymerization apparatus equipped with a slurry preparation tank, an esterification reaction tank, a polycondensation tank, and a pelletizing apparatus, TPA prepared in advance in a slurry tank in an esterification reaction tank containing 50 kg of an esterification reaction product: 38 .8 kg (233.6 mol), CHDA having a trans isomer content of 95% measured by the method described above: 4.5 kg (26.2 mol), EG: 19.3 kg {311 mol (dicarboxylic acid: mol of EG) Ratio = 1: 1.2)} is continuously added at a rate of 15.7 kg / hr, and the esterification reaction is carried out while continuously distilling water produced at 250 ° C. and normal pressure. went. The esterification reaction was terminated by continuing the esterification reaction for another 15 minutes after completion of the slurry feed. After completion of the esterification reaction, 50 kg of the esterification reaction product was left in the esterification reaction tank and transferred to the polycondensation tank.
Subsequently, ethyl acid phosphate (hereinafter abbreviated as “EAP”) was added as a stabilizer, and cobalt acetate tetrahydrate (hereinafter abbreviated as “Co acetate”) and tetrabutoxytitanium (hereinafter abbreviated as “Co acetate”) as polymerization catalysts. (Hereinafter abbreviated as “TBT”) was added (both added as an EG solution). The addition amounts of EAP, Co acetate, and TBT were 12 mass ppm, 100 mass ppm, and 21.3 mass ppm, respectively, with respect to the theoretical yield of the polyester.
Next, while the pressure in the polycondensation tank was reduced from normal pressure to 1 mmHg over about 100 minutes, the internal temperature was increased from about 250 ° C. to about 280 ° C., and the melt polycondensation reaction was performed while distilling EG. After 4 hours from the start of decompression, the pressure was restored and the polycondensation reaction was completed. After returning the pressure in the polycondensation tank, the polyester resin was taken out in a strand form from the lower part of the tank, cooled with water, and pelletized with a cutter to obtain polyester resin pellets.

(2) Polyester resin 2 (PET2)
Polyester resin 2 was produced by the method of Production Example 2 described below. As a result of analyzing the composition of the polyester resin 2 by the above method, 20 mol% in the dicarboxylic acid residue component is a CHDA residue, 80 mol% is a TPA residue, and 98 mol% in the diol residue component is EG. Residues, 2 mol% were DEG residues. Moreover, it was 0.83 dl / g as a result of measuring the intrinsic viscosity of the polyester-type resin 2 by the said method.

<Production Example 2>
TPA at the time of esterification: 34.4 kg (207 mol), CHDA with trans content 95%: 8.9 kg (51.7 mol), EG: 20.9 kg {336.7 mol (dicarboxylic acid: mol of EG) Ratio = 1: 1.3)} was continuously added at a rate of 16.1 kg / hr to conduct the esterification reaction, and polyester resin 2 was prepared in the same manner as in Production Example 1. Produced.

(3) Polyester resin 3 (PET3)
Polyester resin 3 was produced by the method of Production Example 3 described below. As a result of analyzing the composition of the polyester resin 3 by the above method, 30 mol% in the dicarboxylic acid residue component is CHDA residue, 70 mol% is TPA residue, and 98 mol% in the diol residue component is EG. Residues, 2 mol% were DEG residues. Moreover, it was 0.85 dl / g as a result of measuring the intrinsic viscosity of the polyester-type resin 3 by the said method.

<Production Example 3>
At the time of esterification, TPA: 30.0 kg (180.6 mol), trans body content 95% CHDA: 13.3 kg (77.3 mol), EG: 20.8 kg {335.1 mol (dicarboxylic acid: EG) The polyester resin 3 was prepared in the same manner as in Production Example 1 except that the esterification reaction was carried out by continuously adding a slurry having a molar ratio of 1: 1.3)} at a rate of 16.0 kg / hr. Was made.

(4) Polyester resin 4 (PET4)
“NOVAPEX PS600” manufactured by Mitsubishi Chemical Corporation was used as the polyester resin 4. As a result of analyzing the composition of the polyester-based resin 4 by the above method, 70 mol% in the dicarboxylic acid residue component is a TPA residue, 30 mol% is an isophthalic acid residue, and 98 mol in the diol residue component. % Were EG residues and 2 mol% were DEG residues. Moreover, it was 0.72 dl / g as a result of measuring the intrinsic viscosity of the polyester-type resin 4 with the said method.

(5) Polyester resin 5 (PET5)
“EASTAR PETG Copolyester 6763” manufactured by Eastman Chemical Co. was used as the polyester resin 5. As a result of analyzing the composition of the polyester-based resin 5 by the above method, the dicarboxylic acid residue component was 100 mol% of the TPA residue, and the diol residue component was 66 mol% of the total diol residue components as the EG residue. 2 mol% were DEG residues and 32 mol% were CHDM residues. Moreover, it was 0.78 dl / g as a result of measuring the intrinsic viscosity of this polyester resin by the said method.

(6) Polyester resin 6 (PET6)
“NOVADURAN 5008” manufactured by Mitsubishi Engineering Plastics was used as the polyester resin 6. As a result of analyzing the composition of the polyester-based resin 6 by the above method, the dicarboxylic acid residue component was 100 mol% of the TPA residue, and the diol residue component was abbreviated as 1,4-butanediol residue (hereinafter referred to as “BD”). It was 100 mol%. Moreover, it was 0.85 dl / g as a result of measuring the intrinsic viscosity of the polyester-type resin 6 by the said method.

(7) Polyester resin 7 (PET7)
“EMBRACE Copolyester” manufactured by Eastman Chemical Co. was used as the polyester resin 7. As a result of analyzing the composition of the polyester resin 7 by the above method, the dicarboxylic acid residue component is 100 mol% of TPA residue, and the diol residue component is 72 mol% of all diol residues, 20 mol% were CHDM residues and 8 mol% were DEG residues. Moreover, it was 0.83 dl / g as a result of measuring the intrinsic viscosity of the polyester-type resin 7 by the said method.

Example 1
After blending 100 parts by mass of polyester resin 1 (PET1), 215 parts by mass of polyester resin 5 (PET5), and 56 parts by mass of polyester resin 6 (PET6) and drying at 60 ° C. for 24 hours, Toshiba Machine Co., Ltd. Using a TEM 58 mm twin screw extruder, a sheet having a width of 250 mm and a thickness of 0.20 mm was obtained by extrusion onto a cooling roll from a T die die having a width of 300 mm with a time discharge amount of 30 kg. Thereafter, the sheet was passed through a film tenter manufactured by Kyoto Machine Co., Ltd. for 20 seconds at a preheating of 90 ° C., and then stretched 4 times in the direction perpendicular to the casting extrusion direction at a stretching temperature of 75 ° C. and a stretching speed of 500% / min. After the heat treatment, heat treatment was performed at 81 ° C. for 20 seconds to obtain a polyester heat-shrinkable film having a thickness of 50 μm. The polyester heat-shrinkable film was evaluated by the above method. The results are shown in Table 1.

(Examples 2 to 3, Comparative Examples 1 to 4)
Except for blending the raw material polyester resin (A) and / or polyester resin (B) in the blending amounts shown in Table 1, stretching at the stretching temperature shown in Table 1, and heat treating at the heat treatment temperature shown in Table 1. In the same manner as in Example 1, a polyester heat-shrinkable film was obtained and evaluated in the same manner. The results are shown in Table 1.

Example 4
For the production of the intermediate layer, a mixed polyester chip in which 100 parts by mass of polyester resin 1 (PET1) and 150 parts by mass of polyester resin 5 (PET5) was blended was used. Moreover, the pellet which consists of 63 mass parts of polyester-type resin 5 (PET5) was used for manufacture of a front and back layer. The mixed polyester chips of the intermediate layer are ejected by a TEM 58 mm extruder (manufactured by Toshiba Machine) at a time discharge rate of 30 kg, and the mixed polyester chips of both outer layers are 200 mm wide by a 40 mm extruder (manufactured by Sumitomo Heavy Industries, Ltd.) at a time discharge amount of 7.5 kg. The two types of three-layer T die die were coextruded on a cooling roll at 270 ° C. while pulling a vacuum vent. The width was 150 mm, the thickness of both outer layers was 0.025 mm, and the thickness of the intermediate layer was 0.20 mm. A three-layer unstretched sheet was obtained. Next, the sheet was stretched in the same manner as in Example 1 to obtain a laminated heat-shrinkable film having a thickness of 50 μm (both outer layers had a thickness of 5 μm and an intermediate layer had a thickness of 40 μm).
The obtained laminated heat-shrinkable film was evaluated by the above method. The results are shown in Table 1.

(Comparative Example 5)
A copolyester resin was produced by the method of Production Example 4 described below. As a result of analyzing the composition of the copolymerized polyester resin by the above method, 15 mol% in the dicarboxylic acid residue component is CHDA residue, 85 mol% is TPA residue, and 79 mol% in the diol residue component. Are EG residues, 20 mol% are CHDM residues, and 1 mol% is DEG residues. Moreover, it was 0.75 dl / g as a result of measuring the intrinsic viscosity of this copolyester-type resin by the above-mentioned method.

<Production Example 4>
Dimethyl terephthalate: 39.4 kg (202.9 mol), dimethyl-1,4-cyclohexanedicarboxylate with a trans content of 40%: 7.16 kg (35.8 mol), and EG: 28.2 kg (454. 3 mol), CHDM: 6.88 kg (47.7 mol), manganese acetate tetrahydrate was added to the theoretical yield of the copolymerized polyester resin in amounts of 42 mass ppm in terms of manganese atoms, respectively. In addition to a transesterification reaction tank equipped with a thermometer and a distillation pipe, the temperature was gradually raised from 170 ° C. to 230 ° C. over 4 hours, and the transesterification reaction was carried out while distilling off the produced methanol. The total amount of this transesterification reaction product was transferred to a polycondensation reaction tank equipped with a stirrer, a thermometer, and a distillation tube, and orthophosphoric acid, Co acetate, and TBT were all added as an EG solution. The addition amounts of orthophosphoric acid, Co acetate, and TBT are 300 mass ppm in terms of phosphorus atom, 60 mass ppm in terms of cobalt atom, and 5 mass ppm in terms of titanium atom, respectively, with respect to the theoretical yield of the copolyester resin. The amount to be. Next, the internal temperature was gradually raised from 230 ° C., and the inside of the polycondensation reaction tank was gradually reduced in pressure to carry out a polycondensation reaction for 5 hours under a vacuum of 280 ° C. and 1.0 mmHg. After the completion of the polycondensation, the copolymer polyester resin was taken out from the lower part of the polymerization tank in a strand shape, cooled with water, and pelletized with a cutter to obtain a copolymer polyester resin.
Next, using the copolymerized polyester resin, a polyester heat-shrinkable film was obtained in the same manner as in Example 1 except that the polyester polyester resin was stretched at the stretching temperature shown in Table 1 and heat-treated at the heat treatment temperature shown in Table 1. Evaluation was performed in the same manner. The results are shown in Table 1.

Table 1 shows that the heat-shrinkable film composed of the composition of the present invention has a good shrinkage finish in both the case of a single layer (Examples 1 to 3) and the case of a multilayer (Example 4). It can be seen that the film has a cut-off property and a high fusing start temperature, and the deterioration with time is small.
On the other hand, in the case of a film that does not contain a resin corresponding to the polyester resin (A) in the present invention (Comparative Example 4), shrinkable finish and perforation, particularly perforation, are present. It can be seen that the film is inferior to the inventive film (Examples 1 to 4). Further, in the case of a film in which the blending ratio of the polyester resin (A) and the polyester resin (B) is outside the range of the present invention (Comparative Examples 2 and 3), the shrinkage finish and the perforation of the machine are the present invention. However, the film was inferior to the film of the present invention in terms of elongation with time and fusion start temperature. In the case of a film using a copolyester resin (Comparative Example 5), all of shrink finish, perforation, deterioration with elongation, and fusion start temperature were inferior to the film of the present invention. .
Thus, the film composed of the composition of the present invention is a heat-shrinkable film having both good shrinkage finish, perforation, heat resistance and breakage resistance compared to conventional heat-shrinkable films. I understand that there is.

  When the composition of the present invention is formed into a heat-shrinkable film, the film has a good shrink finish, excellent heat resistance and rupture resistance, and can be easily formed along the perforations formed in the film. Can be cut into pieces and peeled off, so that it can be used as a film having various uses such as heat-shrinkable films, heat-shrinkable labels, and food packaging.

Claims (9)

Containing 100 to 1900 parts by mass of the polyester resin (B) with respect to 100 parts by mass of the polyester resin (A) and the following polyester resin (A) and the following polyester resin (B). A polyester resin composition characterized by the above.
(A) a dicarboxylic acid residue component containing an alicyclic dicarboxylic acid residue and a diol residue component mainly composed of an ethylene glycol residue, wherein the alicyclic dicarboxylic acid residue A polyester resin containing 5 mol% or more and 50 mol% or less of the base component.
(B) a dicarboxylic acid residue component whose main component is an aromatic dicarboxylic acid residue other than an isophthalic acid residue, and a diol residue component whose main component is an aliphatic diol residue having 2 to 12 carbon atoms, or A polyester resin comprising a diol residue component mainly composed of an aliphatic diol residue having 2 to 12 carbon atoms and an alicyclic diol residue.   The polyester-based resin composition according to claim 1, wherein the polyester-based resin (A) is a polyester-based resin that does not contain an isophthalic acid residue component.   The polyester resin composition according to claim 1 or 2, wherein the polyester resin (A) has a glass transition temperature of 60C or higher and 80C or lower.   The polyester resin composition according to any one of claims 1 to 3, wherein the alicyclic dicarboxylic acid residue is a 1,4-cyclohexanedicarboxylic acid residue.   The polyester resin composition according to claim 1, wherein the alicyclic diol residue is a 1,4-cyclohexanedimethanol residue.   The heat-shrinkage rate in the main shrinkage direction is 20% or more when the polyester-based resin composition according to any one of claims 1 to 5 is used and is stretched at least in a uniaxial direction and immersed in warm water at 80 ° C for 10 seconds. A polyester-based heat-shrinkable film.   A polyester heat-shrinkable multilayer film having at least one layer of the polyester heat-shrinkable film according to claim 6.   A heat shrinkable label using the polyester heat shrinkable film according to claim 6 or the polyester heat shrinkable multilayer film according to claim 7.   A container equipped with the heat-shrinkable label according to claim 8.