JP2002194114A - Heat-shrinkable polyester-based film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heat-shrinkable polyester-based film having a cloudy ground glass appearance and an ultraviolet-ray shielding property even without applying printing or treatment. SOLUTION: The heat-shrinkable polyester-based film comprises a polyester resin and has light transmittance of <=20% in film wavelength of 380 and light transmittance of <=60% in film wavelength of 400 and haze of 15-60%.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a ripe shrinkable polyester film, and more particularly to a heat-shrinkable polyester film having a ground glass-like appearance and an ultraviolet cut property.

[0002]

2. Description of the Related Art A frosted glass bottle is mainly used as a sake bottle for gifts, but in recent years the amount of bottle used has been reduced due to the fact that the bottle is easily damaged and cannot be used repeatedly. Alternatively, it has been attempted to use a heat shrinkable film label attached to a PET bottle.

As such a label, a heat-shrinkable film made of polyvinyl chloride, polystyrene or the like has been mainly used (JP-A-11-1888).
No. 17), in recent years, there has been a problem that chlorine-based gas is generated when incinerated at the time of disposal, and there are problems such as difficulty in printing with polystyrene. The use is getting attention.

Conventionally, when using these heat-shrinkable films, the films have been subjected to white printing or sandblasting to give a frosted glass finish. However, such films are industrially expensive because of their high processing costs and long delivery times. Was disadvantageous to

Recently, shrink labels have been increasingly used to protect the contents of containers from ultraviolet rays. Conventionally, an ultraviolet cut type shrink film made of polyvinyl chloride has been used, but for the above-mentioned reasons, the demand for an ultraviolet cut type shrink film made of another material is increasing. The specific cutability varies depending on the contents, but in the case of foods and beverages, the deterioration or coloring of the contents occurs at a wavelength of 360 nm to 400 nm, which is ultraviolet light in the long wavelength region, in the long wavelength region, particularly 380 nm and 400 nm. Cutability is important.

However, there is no conventional heat-shrinkable polyester film that cuts the ultraviolet rays in the long wavelength region.

[0007]

SUMMARY OF THE INVENTION An object of the present invention is to provide a heat-shrinkable polyester film having a ground glass-like appearance and an ultraviolet-cutting property without printing or processing.

[0008]

Means for Solving the Problems The present inventor has conducted intensive studies to solve the above-mentioned problems of the prior art, and as a result, by setting the ultraviolet transmittance and haze of the heat-shrinkable polyester film to specific ranges, The inventors have found that the object can be achieved, and based on this, have completed the present invention. That is, the present invention is a film comprising a polyester resin,
A film made of a polyester resin, wherein the film has a light transmittance of 20% or less at a wavelength of 380 and a wavelength of 4
A heat-shrinkable polyester film having a light transmittance of 60% or less at 00 and a haze of 15 to 60%.

In this case, the 45 ° specular gloss is 1
It is preferably at most 00%. In this case, the fine particles are contained in an amount of 0.1 to 10% by weight based on the weight of the film.
Preferably, it is contained.

Further, in this case, it is preferable that the average particle diameter of the fine particles is in the range of 0.001 to 5.0 μm.

Further, in this case, the film is preferably composed of at least two of a fine particle-added layer and a fine particle-free layer.
It is preferable that the film is a laminated film composed of layers.

Further, in this case, it is preferable that the film contains an ultraviolet absorber in an amount of 0.1 to 5% by weight based on the weight of the film.

Further, in this case, it is preferable that the film is a laminated film composed of at least two layers of a layer containing an ultraviolet absorber and a layer containing no ultraviolet absorber.

Further, in this case, the hot water shrinkage of the film is 50% or more in the main shrinking direction at a processing temperature of 95 ° C. for a processing time of 10 seconds, and 0 to 10% in a direction orthogonal to the main shrinking direction. It is preferred that

Further, in this case, it is preferable that the film can be solvent-bonded with 1.3-dioxolane.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION The heat-shrinkable polyester film of the present invention is a film made of a polyester resin, and has a light transmittance of 20% at a wavelength of 380 of the film.
Hereinafter, the light transmittance at a wavelength of 400 is 60% or less, and the haze is 15 to 60%,
Thereby, the above object is achieved.

The heat-shrinkable polyester film of the present invention substantially comprises a polyester resin or a polyester resin and fine particles described below. The polyester resin is preferably produced, for example, from a polyester resin composition containing a polyester having a dicarboxylic acid component and a diol component as components, and a polyester elastomer. In the polyester resin composition, the compounding ratio of the polyester and the polyester-based elastomer,
Usually, the former is 50 to 97% by weight based on the total amount of both.
About 70 to 95% by weight, the latter being 3 to 50% by weight.
It is preferable that the amount is about 5 to 30% by weight.

The dicarboxylic acid component constituting the polyester includes aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid and naphthalenedicarboxylic acid, adipic acid, and the like.
One or more known dicarboxylic acids such as alicyclic dicarboxylic acids such as sebacic acid, decanedicarboxylic acid, and aliphatic dicarboxylic acids such as cyclohexanedicarboxylic acid may be used. The diol component includes ethylene glycol, propylene glycol, triethylene glycol, butylene glycol, diethylene glycol, and neopentyl glycol. One or more known diols such as 1,4-cyclohexane dimethanol and tetramethylene glycol ethylene oxide adduct may be used.

The polyester-based elastomer is, for example, a high-melting crystalline polyester segment (T
m 200 ° C or higher) and a molecular weight of 400 or higher, preferably 40
0-8000 low melting point soft polymer segment (Tm80
C. or lower), and a polyester-based elastomer in which borilactone such as poly-ε-caprolactone is used for the low-melting soft polymer segment is particularly preferable.

In order for the film of the present invention to achieve a specific total light transmittance, haze and haze to give the film a frosted glass appearance, for example,
It is suitable that fine particles such as an inorganic lubricant and an organic lubricant are contained in an amount of 0.1 to 10% by weight, preferably 0.5 to 5% by weight based on the weight of the film. When the content of the fine particles is less than 0.1% by weight, it tends to be difficult to obtain a frosted glass appearance, while when it exceeds 10% by weight, the unevenness of the film surface becomes large and the appearance tends to deteriorate. It is in.

The fine particles may be added before the polymerization of the polyester. Usually, examples of the inorganic lubricant added as the fine particles added after the polymerization of the polyester include kaolin, clay, calcium carbonate, silicon oxide, and calcium terephthalate. And known inert particles such as aluminum oxide, titanium oxide, calcium phosphate, and carbon black.

Similarly, as the organic lubricant added as fine particles, there can be used a cross-linked polymer made of a high-melting organic compound which is insoluble at the time of melt-forming a polyester resin, for example, a polymethacrylate or benzoguanatemin.

The melting point (Tm) of the high melting point organic compound must be higher than the temperature at the time of melt film formation, and the organic compound must maintain its shape at the temperature.

The average particle diameter of the fine particles contained in the film is usually preferably in the range of 0.001 to 15.0 μm. If the particle size is less than 0.001 μm, it tends to be difficult to obtain a ground glass-like appearance.
If it exceeds m, the unevenness of the film surface tends to be large and the appearance tends to be reduced. The particle size is more preferably 0.5
To 12 μm, particularly preferably 1 to 10 μm.
Here, the average particle size of the fine particles is measured by a colder counter method.

The film of the present invention may be optionally
It may contain additives such as a stabilizer, a colorant, an antioxidant, and an antistatic agent.

[0026] The polyester film of the present invention can be obtained from JI
The total light transmittance of the film measured according to SK7105-A is preferably 80 to 90%. If the transmittance is less than 80%, the print on the film becomes difficult to see, while if it exceeds 90%, it becomes difficult to obtain a predetermined haze, and neither is preferable. The transmittance is particularly preferably from 85 to 90%.

The film of the present invention is JISK710.
The haze of the film measured according to 5-A is 15 to
It needs to be 60%. If the haze is less than 15%, a frosted glass appearance cannot be obtained, while 60%
If it exceeds, small characters are difficult to see when printed on the film surface and viewed from the opposite side.

At this time, the specular gloss at 45 degrees is preferably 100% or less, and when it is 100% or more, it is difficult to give a soft matte appearance.

Further, in the film of the present invention, JIS K71
Internal haze measured according to 05-A is 50
% Or less, that is, (internal haze) ≦ (haze)
× 0.5 is preferred. Based on this requirement, in the film of the present invention, by increasing the external haze = [(haze) − (internal haze)) and reducing the internal haze, the frosted glass appearance and the design are improved. Reconciling the properties can be suitably achieved.

The heat-shrinkable polyester film of the present invention may be a single layer as long as it satisfies the requirements of the inner haze.
It is not always easy to reduce the content to 0% or less, and in order to satisfy this requirement, it is necessary to variously select the type, added weight, and particle size of the fine particles.

Therefore, the film of the present invention is preferably a laminated film composed of at least two layers of a fine particle-added layer and a fine particle-free layer. The content of the fine particles in the laminated film is the content based on the total weight of the film including the fine particle-added layer and the fine particle-free layer.

Examples of such a laminated film include a laminated film having a two-layer structure in which a fine particle addition layer is provided on the surface side and a layer containing no fine particles is provided on the inner surface side, and a fine particle addition layer is provided on the surface side. Examples include a laminated film having a three-layer structure in which a layer and a layer containing no fine particles are provided on the inner surface side. In the case of such a laminated film in which a layer containing no fine particles is provided on the inner surface side, even when printing is performed on the inner surface side, small letters are difficult to read or the color tone changes, and the design property is impaired. Does not occur.

Here, in the film of the present invention, the inner side refers to the side facing the bottle or bottle when used as a bottle or bottle label, and the front side refers to the side opposite to the inner side.

The heat-absorbent polyester film of the present invention has a maximum surface roughness (SRmax) of 2.
0 to 8.0 μm, and center plane average roughness (SRa)
Is preferably 0.20 to 0.5 μm. SRma
If x or / and SRa are within the above range, the slip of the film is good and the frequency of occurrence of trouble during processing is low,
Also, the surface roughness is not substantially generated.

The film of the present invention has a wavelength of 380 nm.
Is required to be 20% or less, and the light transmittance at a wavelength of 400 nm is 60% or less.
If the light transmittance at a wavelength of 380 nm exceeds 20% or the light transmittance at a wavelength of 400 nm exceeds 60%, the effect of cutting off ultraviolet rays is weakened, and the effect of protecting the contents is reduced.

As a method for imparting the ultraviolet ray cut property,
The known methods include the following methods. The method includes a method of kneading, coating, and impregnating an ultraviolet absorber. In order to achieve the ultraviolet-cutting property of the present invention, a method of kneading an advantageous ultraviolet absorber is preferable because the thickness of the cut layer is large.

Examples of the ultraviolet ray blocking agent include an organic ultraviolet ray absorbing agent and an inorganic ultraviolet ray blocking agent. Examples of the organic type include indole type, benzotriazole type, benzophenone type, cyanoacrylate type and phenyl salicylate type organic low molecular weight substances.

The heat-shrinkable polyester film of the present invention may be a single layer, but a low-molecular-weight polyester film may be deteriorated due to insufficient heat resistance in the molten state of polyester, or the UV absorber may sublime. In some cases, sufficient ultraviolet ray cut properties cannot be obtained. For this reason, in the present invention, for example, an ultraviolet absorber-added layer is provided on the inner side, and a laminated film having a two-layer structure in which a layer containing no ultraviolet absorber is provided on the front side, and an ultraviolet ray is provided on the intermediate layer and / or the inner side. Examples include a laminated film having a three-layer structure in which an absorber-added layer is provided and a layer containing no ultraviolet absorber is provided on the surface side.

Further, it is preferable to adopt a form of co-extrusion of two or three layers in which a layer containing no ultraviolet absorber is provided on the film surface. In addition, a polymer type absorbent is preferable in terms of the heat resistance. A specific example is Novapex U110 manufactured by Mitsubishi Chemical Corporation. On the other hand, examples of inorganic particles include particles having a particle diameter shorter than the wavelength of visible light. Specific examples include fine titanium oxide particles having a particle size of 0.04 μm or less.

It is preferable to add an antioxidant, a heat stabilizer, a dye, a pigment and the like in order to suppress yellowing of the film by kneading the ultraviolet absorber. Specifically, Ciba Specialty Chemicals
And Irganox 1010.

The film of the present invention has a hot water shrinkage ratio of
In the main shrinkage direction, the temperature is preferably 50% or more at a processing temperature of 95 ° C. and a processing time of 10 seconds, more preferably 50 to 75%. When the shrinkage is less than 5.0%, a thin portion of a bottle or a bottle In this case, the label tends to be insufficiently shrunk. On the other hand, if it exceeds 75%, the shrinkage rate is so large that the label may jump up during passage through the shrinking tunnel, which is not preferable. Here, the main shrinkage direction means a direction in which the heat shrinkage rate is large.

The hot water shrinkage of the film of the present invention is preferably 0 to 10% at a processing temperature of 95 ° C. and a processing time of 10 seconds in a direction orthogonal to the main shrinkage direction. When the shrinkage ratio is less than 0% and the direction of elongation is in the direction of elongation, the horizontal wrinkles of the label generated at the time of shrinkage tend to be hard to disappear. All of these are not preferred because problems arise. The shrinkage ratio is more preferably 1 to 7%.

The glass transition temperature Tg of the film of the present invention is
Usually, it is in the range of about 50 to 90 ° C, preferably 55 to 85 ° C, more preferably 55 to 80 ° C. When the Tg is within this range, the low-temperature shrinkage is sufficient and the natural shrinkage is not too large, and the finish of the label is good.

The film of the present invention comprises benzene, toluene,
Solvents with organic solvents such as aromatic hydrocarbons such as xylene and trimethylpasen, halogenated hydrocarbons such as methylene chloride and chloroform, phenols such as phenol, furans such as tetrahydrofuran, and oxolanes such as 1,3-dioxolan. It preferably has adhesiveness. In particular, from the viewpoint of safety, it is more preferable that 1,3-dioxolane has solvent adhesiveness.

In order to impart solvent adhesion to the film of the present invention, for example, it is effective to copolymerize a polyester with a low Tg component. Next, a method for producing a film of the present invention will be described. After drying polyester, copolymerized polyester, polyester-based elastomer and the like containing an appropriate amount of an inorganic lubricant or the like as fine particles as necessary using a normal hopper dryer, paddle dryer, vacuum dryer, or the like, the temperature is 200 to 320 ° C. And extrude.
In the case of a laminated film, coextrusion may be carried out by using an existing method such as a T-die method or a tubular method. After extrusion, the film is quenched to obtain an unstretched film. In the case of the T-die method, it is preferable to use a so-called electrostatic application contact method at the time of quenching because a film with less unevenness in thickness can be obtained.

The obtained unstretched film is monoaxially or biaxially stretched so that the finally obtained film satisfies the constitutional requirements of the present invention. As a stretching method, in addition to a method of stretching only in the longitudinal direction of the roll, or a method of stretching only in the transverse direction with a tenter, in the known biaxial stretching, the film is strongly stretched in either the longitudinal direction or the transverse direction, and the other is minimized. It is also possible to stretch small. Further, re-stretching may be performed as necessary. The vertical direction means the direction in which the film is taken. In the above stretching, stretching is performed at least 2.0 times or more, preferably 2.5 to 6.0 times in the main shrinkage direction, and if necessary, about 1.1 to 2.0 times in the direction orthogonal to the main shrinkage direction. It is stretched and then heat-treated. If the stretching in the main shrinkage direction is less than 2.5 times, a sufficient shrinkage cannot be obtained, and if it exceeds 6.0 times, the shrinkage does not increase any more.

The heat treatment is usually carried out with tension fixed, but it is also possible to simultaneously relax or tentate by 20% or less. As a heat treatment method, an existing method such as a method of contacting with a heating table or a method of holding a clip in a tenter and the like may be used.

During or after the stretching step, one or both sides of the film may be subjected to a corona discharge treatment before or after the stretching to improve the adhesion of the film to printing dust and / or an adhesive layer. During the above stretching step, it is possible to apply the coating on one side or both sides of the film before or after stretching to improve the adhesiveness of the film, the moldability, the antistatic property, the slipperiness, the light shielding property, etc. is there.

The thickness of the film of the present invention is preferably 15
３００300 μm, more preferably 25-200 μm. When the film of the present invention is in the form of a two-layer laminated film of a fine particle-added layer and a layer containing no fine particles, the fine-particle-added layer is preferably 7 to 150 μm.
m, more preferably from 12 to 50 μm, and the layer containing no fine particles is preferably from 7 to 150 μm, more preferably from 12 to 50 μm.

The heat-shrinkable polyester film of the present invention can be suitably used as a heat-shrinkable label for transparent glass bottles, PET bottles and the like. As a method of use in this case, for example, on the inner surface side of the film of the present invention, if necessary, after printing a product name, a logo mark, a precautionary statement, and coloring, both ends are solvent-adhered to form a cylindrical shape. Label as heat shrink. Next, the heat-shrinkable label is supplied to an automatic label mounting apparatus, and is continuously fitted to a mounting object such as a bottle or a bottle, and is allowed to shrink by passing through a steam tunnel, so that the label is shrunk and the label is mounted on the mounting object. Attach.

[0051]

Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited to these Examples. It was determined by the following method.

(1) Total light transmittance and film haze The haze was measured according to JISK7105-A using a haze measurement [NDH-1001DP] manufactured by Mitsumoto Denshoku Kogyo KK.

(2) Internal Haze Film Zedel oil is applied to both sides of the film, sandwiched between two glass plates, and a haze measuring device [NDH manufactured by Nippon Denshoku Industries Co., Ltd.]
One 1001DP "was measured according to JISK7105-A.

(3) The maximum surface roughness of the film (SRm
ax) and center plane average assembly (SRa) 3D micro shape measuring instrument [ET-30H] manufactured by Kosaka Laboratory Co., Ltd.
K], cutoff 80μm, drive speed 100
It was measured under the condition of μm / s.

(4) Heat Shrinkage The film was cut into a square of 10 cm × 10 cm,
After immersion treatment in hot water of O.5 ° C under no load for 10 seconds and heat shrinking, measure the longitudinal and lateral dimensions of the film,
The heat shrinkage was determined according to the following equation. Heat shrinkage (%) = [(length before shrinkage-length after shrinkage) /
Length before shrinkage] × 100 The direction in which the heat shrinkage rate is large was defined as the main shrinkage direction.

(5) Solvent Adhesion The film was joined into a tube using 1,3-dioxolane, and the tube was cut into a 15 mm width in a direction orthogonal to the flow direction at the time of processing to obtain a sample. The joined portion was peeled by pulling in the above-mentioned direction, and the one having sufficient peeling resistance was designated as solvent adhesiveness “」 ”.

(6) Tg (Glass transition point) Using a DSC (model: DSC220) manufactured by Seiko Denshi Kogyo KK, 10 mg of an unstretched film was heated from -40 ° C to 120 ° C at a rate of 20 ° C / min. , And determined from the obtained endothermic curve. Draw a tangent line before and after the inflection point of the endothermic curve, and
Tg (glass transition point).

The polyesters used in the examples and comparative examples are as follows. Polyester A: polyethylene terephthalate (IV: 0.7
5) Polyester B: Polyester composed of 100 mol% of terephthalic acid, 70 mol% of ethylene glycol and 30 mol% of benzoyl glycol (IV: 0.72) Polyester elastomer C: 70 wt% of polybutylene terephthalate Polyester block copolymer comprising 30% by weight of poly-ε-caprolactone (reduced viscosity (η
sp / c): 1.30)

The fine particles used in Examples and Comparative Examples are as follows. Fine particle a: “Eposter MA1010” (polymethacrylate crosslinked particles, average particle size 10 μm; Nippon Shokubai Co., Ltd.)
Fine particles b: “Eposter MA1006” (polymethacrylate crosslinked particles, average particle size 6 μm; manufactured by Nippon Shokubai Co., Ltd.) Fine particles c: amorphous thyroid (silica particles, average particle size 1.5
μm; manufactured by Fuji Sylysia Ltd.)

(Example 1) As shown in Table 1, as a core layer, 98 parts of polyester obtained by mixing 31% by weight of polyester A, 49% by weight of polyester B and 20% by weight of polyester C was used as an ultraviolet ray cut agent ( A polyester composition prepared by adjusting Ciba Specialty Chemicals Co., Ltd. (trade name: Tinuvin 326) to 2 parts as a skin layer, 31% by weight of polyester A, 49% by weight of polyester B, and 20% by weight of polyester C % Of the polyester composition adjusted to 2 parts with respect to 98 parts of the polyester obtained by mixing the polyester composition at 280 ° C. with a skin / core / skin thickness ratio of 12.5 μm after stretching from a T-die.
The resulting mixture was melt-extruded while being laminated so as to have a thickness of m / 25 μm / 12.5 μm, and rapidly cooled with a chill roll to obtain an unstretched film. The unstretched film is heated at a film temperature of 7 with a tenter.
The film was stretched 4.0 times in the transverse direction at 0 ° C. to obtain a heat-shrinkable polyester film having a thickness of 50 μm.

(Examples 2 to 4 and Comparative Examples 1 to 6) As shown in Table 1, the same procedures as in Example 1 were carried out except that the amount of the ultraviolet ray cut agent added and the type and mixing ratio of the fine particles were changed. A heat-shrinkable polyester film having a thickness of 50 μm was obtained.

The evaluation results of the films obtained in Examples 1 to 4 and Comparative Examples 1 to 6 are also shown in Table 1.

[0063]

[Table 1]

The amounts of the fine particles and the ultraviolet absorbers shown in the table are based on the total weight of the film. As is clear from Table 1, the heat-shrinkable polyester films obtained in Examples 1 to 4 satisfy the requirements for ultraviolet transmittance and haze,
All of them had good ultraviolet ray cut properties, finish properties, and frosted glass appearance.

The heat-shrinkable polyester film of the present invention is high in quality and practical, and is suitable for shrink labels having a frosted glass appearance and ultraviolet cut properties.

On the other hand, the heat-shrinkable polyester films obtained in Comparative Examples 1, 2, 4, and 5 had a ground glass-like appearance, but were inferior in ultraviolet cut properties, and were obtained in Comparative Examples 3 and 6. The heat-shrinkable polyester film is
The frosted glass appearance was inferior. Thus, the heat-shrinkable polyester film of the comparative example was inferior in quality and low in practicality.

[0067]

According to the heat-shrinkable polyester film of the present invention, it has a ground glass appearance without printing or processing, and a sufficient solvent adhesion can be obtained. Therefore,
It is extremely useful as a heat-shrinkable polyester film for labels, particularly for labels having high commercial value.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C08K 5/00 C08K 5/00 C08L 67/00 C08L 67/00 G09F 3/04 G09F 3/04 C // B29K 67:00 B29K 67:00 105: 02 105: 02 105: 16 105: 16 B29L 7:00 B29L 7:00 9:00 9:00 (72) Inventor Takashi Nagano 344 Maeda, Kizu, Oaza, Inuyama-shi, Aichi Prefecture Address Toyobo Co., Ltd. Inuyama Factory F-term (reference) 4F071 AA43 AB18 AB21 AB25 AB30 AE05 AE11 AF07 AF30 AF61 BB06 BC01 BC12 4F100 AK41A AK41B BA01 BA02 BA16 CA07 DE01A JA03A JA20A JL11 JN30A YY24A01 AG03 AE03A03 RC02 RG02 RG04 RG09 RG43 4J002 CF061 CF071 DA036 DE136 DE146 DE236 DH046 DJ016 DJ036 EE037 EG106 EU177 FD057 FD176 GF00

Claims (9)

[Claims] 1. A film comprising a polyester resin, wherein the film has a light transmittance of 20 at a wavelength of 380.
%, A light transmittance at a wavelength of 400 is 60% or less, and a haze is 15 to 60%. 2. A heat-shrinkable polyester film, wherein the internal haze of the film according to claim 1 is 0.5 times or less of the haze. 3. The film according to claim 1 or 2,
A heat-shrinkable polyester film containing fine particles in an amount of 0.1 to 10% by weight based on the weight of the film. 4. An average particle diameter of the fine particles according to claim 3,
A heat-shrinkable polyester film having a thickness in the range of 0.001 to 5.0 µm. 5. A heat-shrinkable polyester film, wherein the film according to claim 3 or 4 is a laminated film comprising at least two layers of a fine particle-added layer and a fine particle-free layer. 6. A heat-shrinkable polyester film according to claim 1, wherein the film contains an ultraviolet absorbent in an amount of 0.1 to 5% by weight based on the weight of the film. 7. A heat-shrinkable polyester film, wherein the film according to claim 6 is a laminated film comprising at least two layers, an ultraviolet absorber-added layer and a layer not containing an ultraviolet absorber. 8. The hot water shrinkage ratio of the film according to any one of claims 1 to 7 is 95 ° C. in the main shrinkage direction.
A heat-shrinkable polyester film characterized by being 50% or more in a treatment time of 10 seconds and 0 to 10% in a direction perpendicular to the main shrinkage direction. 9. A heat-shrinkable polyester film, wherein the film according to claim 1 is solvent-adherable with 1,3-dioxolane.