JP2002210902A - Laminated film for heat shrinkable polypropylene shrink label and container mounted with the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a laminated film for a polypropylene shrink label for improving heating shrinkage factor or particularly a low-temperature shrinkability, and improving a balance between shrink packaging suitability and a recycling efficiency, by reducing a gravity and having an excellent balance between anti-blocking properties and slipperiness and a container such as a PET bottle, a polyolefin bottle, a bottle or the like mounted with the same. SOLUTION: The laminated film for the heat shrinkable polypropylene shrink label has a thickness of a surface layer of 1 to 50% of an overall film thickness. The film is formed by using a resin composition containing a crystalline propylene-α-olefin random copolymer having specific physical properties or 50 to 95 wt.% and a specific alicyclic hydrocarbon resin of 5 to 50 wt.% as an intermediate layer, using a resin composition containing a specific anti- blocking agent of 0.05 to 1.0 pts.wt., with respect to 100 pts.wt. of a crystalline propylene-α-olefin random copolymer having specific physical properties as a surface layer so that the film is at least uniaxially double stretched. The container has the shrink label made of the film mounted thereon.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laminated film for a heat-shrinkable polypropylene shrink label and a container equipped with the same, and more particularly, to a heat-shrinkable polypropylene shrink label having improved heat shrinkage, especially low temperature shrinkability. The present invention relates to a laminated film for use and a container equipped with the same.

[0002]

2. Description of the Related Art In recent years, the purpose of packaging is to improve the appearance of packaging articles, to prevent the contents from being directly impacted, to tightly package, to protect glass bottles or plastic bottles, and to label packaging that combines the display of goods. Shrink labels are widely used. As plastic materials used for these purposes, polyvinyl chloride, polystyrene, polyethylene terephthalate, polypropylene and the like are known. However, although the polyvinyl chloride label is excellent in heat shrinkability, it has a problem of environmental pollution such as generation of chlorine gas when incinerated. Polystyrene and polyethylene terephthalate labels have good heat shrinkability, but have a small specific gravity difference from polyethylene terephthalate bottles (hereinafter abbreviated as “PET bottles”), so that floating separation is difficult, and PET bottles are difficult. Hinder recycling. Furthermore, in order to obtain sufficient heat shrinkability, a resin having poor heat resistance is used, and there is a problem that when retort sterilization is performed, a printing ink flow is caused by a molten resin. Polypropylene has a large difference in specific gravity from a PET bottle, is easy to float and separate, and is excellent in heat resistance, but is insufficient in heat shrinkability. In particular, a method of adding a propylene / butene-1 copolymer and a method of adding a petroleum resin or a terpene resin to polypropylene for the purpose of improving low-temperature shrinkability (Japanese Patent Application Laid-Open No. 62-62846) are known. However, the effect is still insufficient, and further improvement in shrinkage performance of a polypropylene resin as a base is desired.

[0003] In addition, the resin composition to which the above petroleum resin is added tends to stick to the chill roll at the time of forming a film, particularly at the time of extruding the unstretched sheet, and the moldability deteriorates. In order to improve the moldability, when a polypropylene-based resin that does not add petroleum resin is laminated on the surface layer, the intermediate layer does not have sufficient heat shrinkage properties,
There is a problem that the heat shrinkage rate is reduced. In order to solve the above-mentioned problem, the appearance of an intermediate layer exhibiting an excellent heat shrinkage rate has been desired.

Further, a polypropylene shrink label film satisfying the above-mentioned low-temperature shrinkage property, transparency, anti-blocking property and sliding property in a well-balanced manner has not been found so far. In addition, a conventional polypropylene shrink label has an increased specific gravity when the heat shrinkage rate is improved, and the efficiency of floating separation from a PET bottle by water during recycling deteriorates. Therefore, the appearance of a polypropylene-based shrink label film having as low a specific gravity as possible and having an improved heat shrinkage rate has been desired.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to improve the heat shrinkage, especially the low temperature shrinkage, and improve the balance between shrink packaging suitability and recycling efficiency by lowering the specific gravity under such circumstances. And, a laminated film for a polypropylene-based shrink label having an excellent balance of transparency, antiblocking property and slipperiness, and a PET bottle and a polyolefin bottle equipped with the laminated film,
It is to provide a container such as a bottle.

[0006]

The inventors of the present invention have conducted various studies to solve the above-mentioned problems, and as a result, as a middle layer, a specific crystalline propylene / α-olefin random copolymer and a specific fat Using a resin composition containing a cyclic hydrocarbon resin and a resin composition containing a specific crystalline propylene / α-olefin random copolymer and a specific antiblocking agent as a surface layer to form a laminated film. As a result, they have found that a heat shrinkable polypropylene-based shrink label laminated film that can solve the above-mentioned problems can be obtained, and have completed the present invention.

That is, according to the first aspect of the present invention,
Surface layer (II) laminated on one or both sides of intermediate layer (I)
Laminated at least twice in the uniaxial direction.
Surface layer laminated on one or both sides
(II) is 1 to 50% of the total film thickness
And the intermediate layer (I) satisfies the following characteristics (a) to (c).
Crystalline propylene mainly composed of propylene
Olefin random copolymer (1) 50 to 95% by weight
And an alicyclic hydrocarbon tree having a softening point temperature of 110 ° C. or higher
And a resin layer containing 5 to 50% by weight of a fat.
(II) propylene satisfying the following properties (d) to (e)
Crystalline propylene / α-olefin lan
With respect to 100 parts by weight of the dam copolymer (2), the volume average particle
Antiblocking agent having a diameter of 1.0 to 10 μm
Heat recovery comprising a resin composition containing 0.5 to 1.0 parts by weight
Shrinkable polypropylene shrink label laminated film
Is provided. Intermediate layer (I) Characteristics (a): melt flow rate (230 ° C., 2.16
kg load) is 0.5 to 10 g / 10 min. Characteristic (b): Mainly determined by a differential scanning calorimeter (DSC)
Melting peak temperature (T _P) In the range of 100-140 ° C
There is. Characteristic (c): T₅₀≤125 ° C (However, T₅₀Is the crystalline propylene determined by DSC
・ Total heat of fusion of α-olefin random copolymer (1)
Is ΔHm, the heat of fusion calculated from the low temperature side is ΔHm.
This is the temperature (° C.) at which 50% of Hm is reached. ) Surface layer (II) Characteristics (d): melt flow rate (230 ° C, 2.16)
kg load) is 0.5 to 50 g / 10 min. Characteristic (e): Mainly determined by a differential scanning calorimeter (DSC)
Melting peak temperature (T _p) In the range of 100-150 ° C
There is.

According to the second aspect of the present invention, the first aspect is provided.
In the invention, the crystalline propylene / α-olefin random copolymer (1) and the crystalline propylene / α
The olefin random copolymer (2) is propylene
A laminated film for a heat-shrinkable polypropylene shrink label, which is an ethylene random copolymer, is provided.

Further, according to the third aspect of the present invention, the first aspect is provided.
Or the crystalline propylene α-
A laminated film for a heat-shrinkable polypropylene shrink label, which is a copolymer obtained by polymerizing an olefin random copolymer (1) with a metallocene catalyst, is provided.

According to the fourth aspect of the present invention, the first aspect is provided.
In any one of the inventions of (1) to (3), the shrinkage rate in the main shrinkage direction satisfies the following formula (1) and the specific gravity is 0.94 or less, and the shrinkage rate in the main shrinkage direction at 40 ° C. for 7 days is less than 3%. The heat-shrinkable polypropylene-based shrink label laminated film is provided. Formula: S ₈₀ > 251d-215 Formula: S ₉₀ > 531d-462 Formula: S ₁₀₀ > 627d-541 (However, S ₈₀ , S ₉₀ , and S ₁₀₀ are each 80 ° C.
The shrinkage ratio (%) in the main shrinkage direction when heated in a hot water bath at 90 ° C. and 100 ° C. for 10 seconds, and d is the specific gravity of the laminated film for shrink labels. )

According to a fifth aspect of the present invention, the first aspect is provided.
A heat-shrinkable label having a specific gravity of less than 1.0, comprising the heat-shrinkable polypropylene-based shrink label laminated film according to any one of the first to fourth inventions.

Further, according to a sixth aspect of the present invention, there is provided a container provided with the heat-shrinkable label according to the fifth aspect.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, a laminated film for a heat-shrinkable polypropylene shrink label and a container equipped with the same according to the present invention will be described in detail.

[I] Intermediate layer (I) Crystalline propylene / α-olefin random copolymer (1) (1) Property (a): melt flow rate MFR of the crystalline propylene / α-olefin random copolymer (1) used in the present invention (230 ° C, 2 .16 kg
Load, hereinafter abbreviated as “MFR”. ) Is 0.5 to 10 g
/ 10 minutes, preferably 1.0 to 10 g / 10 minutes.
If the MFR is less than 0.5 g / 10 minutes, the extrusion characteristics may be deteriorated and the productivity may be reduced.
Exceeding the number of minutes will deteriorate the shrinkage characteristics and cause uneven thickness.

[0015] (2) Characteristics (b): The main melting peak temperature obtained by DSC of DSC in the obtained primary melting peak temperature _(T P) crystalline propylene · alpha-olefin random copolymer used in the present invention (1) (T _P ) is 100 to 140 ° C., preferably 100
To 130 ° C, more preferably 100 to 125 ° C. When the melting peak temperature (T _P ) is less than 100 ° C., the unstretched sheet is difficult to be solidified by cooling, and film forming becomes difficult.

(3) Property (c): Relationship between heat of fusion and temperature The crystalline propylene / α-olefin random copolymer (1) used in the present invention needs to satisfy the following formula. T ₅₀ ≦ 125 ° C. (where T ₅₀ is ΔHm when the total heat of fusion of the crystalline propylene / α-olefin random copolymer (1) determined by DSC is ΔHm,
It is the temperature (° C.) at which 50% of Hm is reached. ) T ₅₀ is 125 ° C or lower _, preferably 120 ° C or lower;
More preferably, it is 115 ° C. or lower. T ₅₀ is 125
If the temperature exceeds ℃, the shrinkage characteristics deteriorate.

(4) Constituents of the crystalline propylene / α-olefin random copolymer (1) The α of the crystalline propylene / α-olefin random copolymer (1) used in the present invention is randomly copolymerized with propylene. -As the olefin, ethylene or a carbon number of 4 to
20 α-olefins, ethylene, butene
It is preferable to use 1, hexene-1, octene-1, and the like, and particularly preferable is ethylene.

The crystalline propylene / α-olefin random copolymer (1) of the present invention has the above properties (a) to (c).
As long as it satisfies, the α-olefin content in the random copolymer is usually 2.0 to 30.
%, Especially when the α-olefin is ethylene, about 2.0 to 10% by weight, preferably 2.0% by weight.
About 6.0% by weight. Further, the above characteristics (a) to
If (c) is satisfied, the crystalline propylene / α-olefin random copolymer (1) may be a mixture of two or more kinds.

(5) Method for producing crystalline propylene / α-olefin random copolymer (1) The crystalline propylene / α-olefin random copolymer (1) used in the present invention is polymerized using a metallocene catalyst. In particular, propylene and ethylene or an α-olefin having 4 to 20 carbon atoms in the presence of a metallocene catalyst comprising the following catalyst component (A), component (B) and, if necessary, component (C). And those produced by random copolymerization of

[0020] (i) a metallocene catalyst component ^{_{(A) Q (C 5 H}} 4-a R 1 a) (C 5 H 4-b R 2 b) Me
XY ^{_{(where, C 5 H 4-a R}} 1 a and _C 5 _{H 4-b} ^{R 2}
_b represents a conjugated five-membered ring ligand, and Q represents a binding group bridging two conjugated five-membered ring ligands, and has 1 carbon atom.
X represents a divalent hydrocarbon group having a hydrocarbon group of 1 to 20; a silylene group having a hydrocarbon group having 1 to 20 carbon atoms; or a germylene group having a hydrocarbon group having 1 to 20 carbon atoms; Me represents zirconium or hafnium; Y is independently hydrogen, halogen, a hydrocarbon group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, an alkylamide group having 1 to 20 carbon atoms, a trifluoromethanesulfonic acid group, And represents a phosphorus-containing hydrocarbon group having from 20 to 20 or a silicon-containing hydrocarbon group having from 1 to 20 carbon atoms. R ¹ and R ² are substituents on a conjugated five-membered ring ligand, each independently
A hydrocarbon group having 1 to 20 carbon atoms, a halogen, an alkoxy group, a silicon-containing hydrocarbon group, a phosphorus-containing hydrocarbon group, a nitrogen-containing hydrocarbon group or a boron-containing hydrocarbon group. Two adjacent R ¹ or two R ² may be bonded to each other to form a ring. a and b are 0 ≦ a ≦ 4, 0
It is an integer satisfying ≦ b ≦ 4. Where R ¹ and R
^{The two} five-membered ligands having 2 are asymmetric with respect to the plane containing Me in terms of their relative positions via the group Q. )

Q is, as described above, two conjugated five-membered rings.
Ligand C₅H_4-aR¹ _aAnd C ₅H_4-bR² _bTo
A crosslinkable bonding group, specifically, for example, (a)
Divalent hydrocarbon having 1 to 20, preferably 1 to 6 carbon atoms
Group, specifically, for example, an alkylene group, cycloalkylene
Groups, arylene, etc., (b) 1-20 carbon atoms, preferred
A silylene group having 1 to 12 hydrocarbon groups;
Having a hydrocarbon group of 1 to 20, preferably 1 to 12 carbon atoms
There are germylene groups. In addition, both conjugation of the divalent Q group
The distance between the joints is Q regardless of the carbon number.
In the case of a chain, less than about 4 atoms, especially less than 3 atoms
When Q has a cyclic group,
A cyclic group plus about 2 atoms or less, especially
It is respectively preferable. Therefore, the field of alkylene
If ethylene and isopropylidene (the distance between the bonds)
Is 2 and 1 atom) is a cycloalkylene group
Is cyclohexylene (the distance between the bonds is cyclohexylene
Dimethylsilicylene)
Rylene (one atom between bonds) is preferred
No.

Me is zirconium or hafnium.

X and Y may be each independently, that is, they may be the same or different, and (A) hydrogen, (B) halogen (fluorine, chlorine, bromine or iodine, preferably chlorine), A hydrocarbon group having 1 to 20 carbon atoms, (d) an alkoxy group having 1 to 20 carbon atoms, (e) an alkylamide group having 1 to 20 carbon atoms, (f) a phosphorus-containing hydrocarbon group having 1 to 20 carbon atoms, (g) It represents a silicon-containing hydrocarbon group having 1 to 20 carbon atoms or a (thi) trifluoromethanesulfonic acid group.

R¹And R²Is on the conjugated five-membered ring ligand
Substituents, each independently having 1 to 20 carbon atoms
Hydrocarbon group, halogen, alkoxy having 1 to 20 carbon atoms
Group, silicon-containing hydrocarbon group having 3 to 20 carbon atoms, 2 carbon atoms
To 20 phosphorus-containing hydrocarbon groups and 2 to 20 carbon atoms containing nitrogen
A hydrocarbon group or a boron-containing hydrocarbon having 2 to 20 carbon atoms
Represents an elementary group. In addition, two adjacent R¹Two or two
R²Are bonded to each other at the ω-
A ring may be formed together with a part of the enyl group. That's it
A typical example of such a case is that on the cyclopentadienyl group
Two adjacent R ¹(Or R²) Is the cyclopen
Form a fused six-membered ring by sharing the double bond of the tadienyl group
(Ie, indenyl and fluorenyl)
Group) and those forming a fused seven-membered ring (ie,
Zurenyl group).

A and b are integers satisfying 0 ≦ a ≦ 4 and 0 ≦ b ≦ 4.

Non-limiting examples of the above metallocene compounds include the following. In addition, these compounds are indicated by only chemical names, but needless to say, the three-dimensional structure has the asymmetry referred to in the present invention.

(A1) a transition metal compound having two silylene-bridged five-membered ring ligands, for example, (1) dimethylsilylenebis (1-indenyl) zirconium dichloride;
(2) dimethylsilylenebis {1- (4,5,6,7-
Tetrahydroindenyl) zirconium dichloride,
(3) dimethylsilylenebis {1- (2,4-dimethylindenyl)} zirconium dichloride, (4) dimethylsilylenebis {1- (2-methyl-4-phenylindenyl)} zirconium dichloride, (5) dimethyl Silylene bis {1- (2-methyl-4-phenyl-4H-)
Azulenyl) {zirconium dichloride, (6) dimethylsilylenebis} 1- (2-methyl-4-phenyl-4)
H-5,6,7,8-tetrahydroazulenyl) {zirconium dichloride, (7) dimethylsilylenebis} 1
-(2-methyl-4- (4-chlorophenyl) -4H-
Azulenyl) {zirconium dichloride, (8) dimethylsilylenebis {1- (2-methyl-4- (4-chlorophenyl) -4H-5,6,7,8-tetrahydroazulenyl)} zirconium dichloride, (9) dimethyl Silylenebis {1- (2-methyl-4,5-benzoindenyl)} zirconium dichloride, (10) dimethylsilylenebis [1- {2-methyl-4- (1-naphthyl)]
Indenyl}] zirconium dichloride, (11) dimethylsilylene bis [1- {2-methyl-4- (1-naphthyl) -4H-azulenyl}] zirconium dichloride, (12) dimethylsilylenebis [1- {2-methyl- 4- (1-naphthyl) -4H-5,6,7,8-tetrahydroazulenyl}] zirconium dichloride, (1
3) methylphenylsilylenebis (1-indenyl) zirconium dichloride, (14) methylphenylsilylenebis {1- (4,5,6,7-tetrahydroindenyl)} zirconium dichloride, (15) methylphenylsilylenebis} 1 -(2,4-dimethylindenyl) {zirconium dichloride, (16) methylphenylsilylenebis {1- (2-methyl-4-phenylindenyl)} zirconium dichloride, (17) methylphenylsilylenebis} 1- ( 2-methyl-4-phenyl-4H-azulenyl) zirconium dichloride, (1
8) Methylphenylsilylenebis {1- (2-methyl-)
4-phenyl-4H-5,6,7,8, -tetrahydroazulenyl) {zirconium dichloride, (19) methylphenylsilylenebis} 1- (2-methyl-4,5-
Benzoindenyl) zirconium dichloride, (2
0) methylphenylsilylenebis [1- {2-methyl-
4- (1-naphthyl) indenyl}] zirconium dichloride, (21) methylphenylsilylenebis [1-
{2-methyl-4- (1-naphthyl) -4H-azulenyl}] zirconium dichloride, (22) methylphenylsilylenebis [1- {2-methyl-4- (1-naphthyl) -4H-5,6, 7,8-tetrahydroazulenyl}] zirconium dichloride, (23) dimethylsilylenebis {1- (2-methyl-4,5-benzoindenyl)} zirconiumdimethyl, (24) dimethylsilylenebis {1- (2- Methyl-4,5-benzoindenyl) zirconium methyl chloride, (25) dimethylsilylenebis {1- (2-methyl-4-phenylindenyl)} zirconiumdimethyl, (26) dimethylsilylenebis} 1- (2 -Methyl-4-phenyl-4H-azulenyl) {zirconium dimethyl, (27) dimethylsilylenebis} 1- ( - methyl-4-phenyl indenyl)} zirconium chloro dimethylamide, (28)
Dimethylsilylenebis {1- (2-ethyl-4,5-benzoindenyl)} zirconium dichloride, (29)
(30) Dimethylsilylenebis {1- (2-ethyl-4-phenylindenyl)} zirconium dichloride, (30) dimethylsilylenebis {1- (2-ethyl-4-phenyl-4H-azulenyl)} zirconium dichloride, (3
1) dimethylsilylenebis {1- (2-ethyl-4-phenyl-4H-5,6,7,8-tetrahydroazulenyl)} zirconium dichloride, (32) dimethylsilylenebis {1- (2-ethyl-4) -(Chlorophenyl)
-4H-azulenyl) zirconium dichloride, (3
3) dimethylsilylenebis {1- (2-ethyl-4-)
(4-chlorophenyl) -4H-5,6,7,8-tetrahydroazulenyl) zirconium dichloride, (3
4) Dimethylsilylene {1- (2-ethyl-4-phenylindenyl)} 1- (2,3,5-trimethylcyclopentadienyl)} zirconium dichloride, (3
5) Dimethylsilylene {1- (2-ethyl-4-phenyl-4,5,6,7,8-pentahydroazulenyl)}
{1- (2,3,5-trimethylcyclopentadienyl)} zirconium dichloride, (36) dimethylsilylenebis} 1- (2-methyl-4,4-dimethyl-sila-4,5,6,7- Tetrahydroindenyl) {zirconium dichloride, (37) dimethylsilylenebis} 1
-(2-ethyl-4-phenylindenyl) zirconium bis (trifluoromethanesulfonic acid), (38)
Dimethylsilylenebis {1- (2-ethyl-4-phenylazulenyl)} zirconiumbis (trifluoromethanesulfonic acid), (39) dimethylsilylenebis {1-
(2-ethyl-4-phenyl-4,5,6,7,8-pentahydroazulenyl) {zirconium bis (trifluoromethanesulfonic acid), (40) dimethylsilylenebis} 1- (2-ethyl-4- (Pentafluorophenyl) indenyl) zirconium dichloride, (41)
Dimethylsilylenebis {1- (2-ethyl-4-phenyl-7-fluoroindenyl)} zirconium dichloride, (42) dimethylsilylenebis {1- (2-ethyl-4-indolylindenyl)} zirconium dichloride, (43) Dimethylsilylene bis {1- (2-dimethylborano-4-indolylindenyl)} zirconium dichloride.

(A2) Transition metal compounds having two five-membered ligands bridged by an alkylene group, for example, (1) ethylene-1,2-bis (1-indenyl) zirconium dichloride, (2) ethylene-1 , 2-bis @ 1- (4,
(5,6,7-tetrahydroindenyl)} zirconium dichloride, (3) ethylene-1,2-bis {1-
(2,4-dimethylindenyl) {zirconium dichloride, (4) ethylene-1,2-bis} 1- (2,4-
Dimethyl-4H-azulenyl) {zirconium dichloride, (5) ethylene-1,2-bis {1- (2-methyl-4-phenylindenyl)} zirconium dichloride, (6) ethylene-1,2-bis} 1 -(2-methyl-4-phenyl-4H-azulenyl) {zirconium dichloride, (7) ethylene-1,2-bis} 1- (2-
Methyl-4,5-benzoindenyl) zirconium dichloride, (8) ethylene-1,2-bis [1- {2-
Methyl-4- (1-naphthyl) indenyl}] zirconium dichloride, (9) ethylene-1,2-bis [1-
{2-methyl-4- (1-naphthyl) -4H-azulenyl}] zirconium dichloride, (10) ethylene-
1,2-bis [1- {2-methyl-4- (4-chlorophenyl) -4H-azulenyl}] zirconium dichloride and the like.

(A3) Transition metal compound having a five-membered ring ligand bridged by a hydrocarbon residue containing germanium, aluminum, boron, phosphorus or nitrogen, such as (1) dimethylgermylene bis (1-indenyl) zirconium Dichloride, (2) dimethylgermylene bis {1- (2
-Methyl-4-phenylindenyl) {zirconium dichloride, (3) dimethylgermylene bis} 1- (2-
Methyl-4-phenyl-4H-azulenyl) {zirconium dichloride, (4) dimethylgermylene bis} 1-
(2-methyl-4- (4-chlorophenyl) -4H-azulenyl)｝ zirconium dichloride, (5) dimethylgermylene bis ｛1- (2-methyl-4,5-benzoindenyl)｝ zirconium dichloride, (6 ) Methylaluminum bis (1-indenyl) zirconium dichloride, (7) phenylphosphinobis (1-indenyl) zirconium dichloride, (8) ethylholanobis (1-indenyl) zirconium dichloride, (9) phenylaminobis (1-indenyl) Zirconium dichloride and the like can be mentioned.

Particularly preferred among these complexes are complexes having an azulene skeleton.

Component (B) As the component (B), an ion-exchange layered silicate is used. The ion-exchange layered silicate is a silicate compound having a crystal structure in which planes formed by ionic bonds and the like are stacked in parallel with a weak bonding force to each other. Most ion-exchanged phyllosilicates occur naturally mainly as a main component of clay minerals, but these ion-exchanged phyllosilicates are not limited to those of natural origin but are artificially synthesized. You may. Specific examples of ion-exchangeable layered silicates include known layered silicates described in, for example, "Clay Mineralogy" written by Haruo Shimizu, Asakura Shoten (1995), and include dickite, nacrite, kaolinite, and the like. Kaolin, chrysotile, such as anoxite, meta halloysite, halloysite,
Serpentine group such as lizardite, antigolite, montmorillonite, sauconitic, beidellite, nontronite, saponite, hectorite, smectite group such as stevensite, vermiculite group such as vermiculite, mica, illite, sericite, marine green stone, etc. Mica, attapulgite, sepiolite, palygorskite, bentonite, pyrophyllite, talc,
Chlorite group. These may form a mixed layer.

Among these, montmorillonite, zaukonite, beidellite, nontronite, saponite,
Smectites such as hectorite, stevensite, bentonite, and teniolite, vermiculites,
Mica is preferred. When a compound having a radius of 20 angstroms or more measured by a mercury intrusion method and having a pore volume of less than 0.1 cc / g is used as the component (B), a high polymerization activity tends to be hardly obtained. 0.1 cc / g or more, particularly preferably 0.3 to 5 cc / g. Also,
Although the component (B) can be used without any particular treatment, it is also preferable to subject the component (B) to a chemical treatment. Here, the chemical treatment may be any of a surface treatment for removing impurities adhering to the surface and a treatment that affects the structure of the clay.

Specific examples include acid treatment, alkali treatment, salt treatment, and organic treatment. The acid treatment removes impurities on the surface and increases the surface area by eluting cations such as Al, Fe, and Mg in the crystal structure. Alkali treatment destroys the crystal structure of the clay, resulting in a change in the structure of the clay. In the salt treatment and the organic substance treatment, an ion complex, a molecular complex, an organic derivative, and the like are formed, and the surface area and the interlayer distance can be changed. By replacing the exchangeable ions between the layers with another large bulky ion by utilizing the ion exchange property, a layered material in which the layers are expanded can be obtained. That is, the bulky ions play a pillar-like role of supporting the layered structure, and are called pillars. Introducing another substance between layered substance layers is called intercalation.

The guest compounds to be intercalated include cationic inorganic compounds such as TiCl ₄ and ZrCl ₄ , Ti (OR) ₄ , Zr (OR) ₄ and PO (O
_{R) 3, B (OR)} 3 (R is alkyl, aryl, etc.) or the like of the metal _{alcoholate, [Al 1 3 O 4 (} OH) 24]
⁷⁺ , [Zr ₄ (OH) ₁₄ ] ²⁺ , [Fe ₃ O (OC
And metal hydroxide ions such as OCH ₃ ) ₆ ] ⁺ . These compounds may be used alone or in combination of two or more. When intercalating these compounds, Si (OR) ₄ , Al (O
A polymer obtained by hydrolyzing a metal alcoholate such as R) ₃ or Ge (OR) _4, a colloidal inorganic compound such as SiO _2, and the like can also coexist. Examples of pillars include oxides formed by intercalating the hydroxide ions between layers and then heating and dehydrating. Component (B) may be used as it is, or may be used after heat dehydration treatment. Further, they may be used alone or as a mixture of two or more of the above solids.

The ion-exchangeable phyllosilicate used in the present invention is preferably at least 40%, preferably not less than 40%, of the exchangeable Group 1 metal cation contained in the ion-exchange phyllosilicate before being treated with salts. Preferably, 60% or more is ion-exchanged with a cation dissociated from the following salts. The salt used in the salt treatment for the purpose of ion exchange is a compound containing a cation containing at least one atom selected from the group consisting of Group 2 to 14 atoms, preferably 2 to 14 A cation containing at least one atom selected from the group consisting of group atoms, a halogen atom, a compound consisting of at least one anion selected from the group consisting of inorganic acids and organic acids, more preferably, A cation containing at least one atom selected from the group consisting of Group 2 to 14 atoms, Cl, Br,
I, F, PO ₄ , SO ₄ , NO ₃ , CO ₃ , C ₂ O ₄ ,
OCOCH ₃ , CH ₃ COCHCOCH ₃ , OCl ₃ ,
O (NO ₃ ) ₂ , O (ClO ₄ ) ₂ , O (SO ₄ ), O
H, O ₂ Cl ₂ , OCl ₃ , OCOH, OCOCH ₂ C
H _3, which is a compound consisting of _{the C} 2 _{H 4 O} 4 and _C 6 _H 5 at least one anion chosen from the group consisting of _{O 7.}

Specifically, CaCl₂, CaSO₄, C
aC₂O₄, Ca (NO₃)₂, Ca₃(C₆H
₅O₇)₂, MgCl₂, MgBr₂, MgSO₄, M
g (PO₄)₂, Mg (ClO₄)₂, MgC₂O₄,
Mg (NO₃)₂, Mg (OCOCH₃)₂, MgC₄
H₄O₄, Sc (OCOCH₃)₂, Sc₂(CO₃)
₃, Sc₂(C₂O₄)₃, Sc (NO₃)₃, Sc₂
(SO₄)₃, ScF₃, ScCl₃, ScBr₃, S
cI₃, Y (OCOCH₃)₃, Y (CH₃COCHC
OCH₃)₃, Y₂(CO₃)₃, Y₂(C
₂O₄)₃, Y (NO₃)₃, Y (ClO₄)₃, YP
O₄, Y₂(SO₄)₃, YF₃, YCl₃, La (O
OCH₃)₃, La (CH₃COCHCOCH₃)₃,
La₂(CO₃)₃, La (NO₃)₃, La (ClO
₄)₃, La₂(C₂O₄)₃, LaPO₄, La
₂(SO₄)₃, LaF₃, LaCl₃, LaBr
₃ , LaI₃, Sm (OCOCH₃)₃, Sm (CH
₃COCHCOCH₃)₃, Sm₂(CO₃)₃, Sm
(NO₃)₃, Sm (ClCO₄)₃, Sm₂(C₂O
₄)₃, SmPO₄, Sm₂(SO₄)₃, SmF₃,
SmCl₃, SmBr₃, SmI₃, Yb (OCOCH
₃)₃, Yb (NO₃)₃, Yb (ClO₄)₃, Yb
(C₂O₄)₃, Yb (SO₄)₃, YbF₃, YbC
l₃, Ti (OCOCH₃)₄, Ti (CO₃)₂, T
i (NO₃)₄, Ti (SO₄)₂, TiF₄, TiC
l₄, TiBr₄, TiI₄, Zr (OCOC
H₃)₄, Zr (CO₃)₂, Zr (NO ₃)₄, Zr
(SO₄)₂, ZrF₄, ZrCl₄, ZrBr₄, Z
rI₄, ZrOCl₂, ZrO (NO₃)₂, ZrO
(ClO₄)₂, ZrO (SO₄), Hf (OCOCH
₃)₄, Hf (CO₃)₂, Hf (NO₃)₄, Hf
(SO₄)₂, HfOCl₂, HfF₄, HfCl₄,
HfBr₄, HfI₄, V (CH ₃COCHCOC
H₃)₃, VOSO₄, VOCl₃, VCl₃, VCl
₄, VBr₃, Nb (CH₃COCHCOCH₃)₅,
Nb₂(CO₃)₅, Nb (NO₃)₅, Nb₂(SO
₄)₅, ZrF₅, ZrCl₅, NbBr₅, Nb
l₅, Ta (OCOCH₃)₅, Ta₂(CO3)₅,
Ta (NO)₅, Ta₂(SO₄)₅, TaF₅, Ta
Cl₅, TaBr₅, TaI₅, Cr (OOCH₃) ₂
OH, Cr (CH₃COCHCOCH₃)₃, Cr (N
O₃)₃, Cr (ClO₄)₃, CrPO₄, Cr
₂(SO₄)₃, CrO₂Cl₂, CrF₃, CrCl
₃, CrBr₃, CrI₃, MoOCl₄, MoC
l₃, MoCl₄, MoCl₅, MoF₆, MoI₂,
WCl₄, WCl₆, WF₆, WBr₅, Mn (OOC
H₃)₂, Mn (CH₃COCHCOCH₃)₂, Mn
CO₃, Mn (NO₃)₂, MnO, Mn (ClO₄)
₂, MnF₂, MnCl₂, MnBr₂, MnI₂, F
e (OCOCH₃)₂, Fe (CH₃COCHCOCH
₃)₃, FeCO₃, Fe (NO₃)₃, Fe (ClO
₄)₃, FePO₄, FeSO₄, Fe₂(S
O₄)₃, FeF₃, FeCl₃, FeBr₃, FeI
₂, FeC₆H₅O₇, Co (OCOCH₃)₂, Co
(CH₃COCHCOCH₃)₃, CoCO₃, Co
(NO₃)₂, CoC₂O₄, Co (ClO₄)₂, C
o₃(PO₄)₂, CoSO₄, CoF₂, CoC
l₂, CoBr₂, CoI₂, NiCO₃, Ni (NO
₃)₂, NiC₂O₄, Ni (ClO₄)₂, NiSO
₄, NiCl₂, NiBr₂, Pb (OCOC
H₃)₄, Pb (OOCH₃)₂, PbCO₃, Pb
(NO₃)₂, PbSO₄, PbHPO₄, Pb (Cl
O₄)₂, PbF₂, PbCl₂, PbBr₂, PbI
₂, CuI₂, CuBr₂, Cu (NO₃)₂, CuC
₂O₄, Cu (ClO₄)₂, CuSO₄, Cu (OC
OCH₃)₂, Zn (OOCH₃)₂, Zn (CH₃C
OCHCOCH₃)₂, ZnCO₃, Zn (N
O₃)₂, Zn (ClO₄)₂, Zn₃(PO₄)₂,
ZnSO₄, ZnF₂, ZnCl₂, ZnBr₂, Zn
I₂, Cd (OCOCH₃)₂, Cd (CH₃COCH
COCH₃)₂, Cd (OCOCH₂CH₃)₂, Cd
(NO₃)₂, Cd (ClO₄)₂, CdSO₄, Cd
F₂, CdCl₂, CdBr₂, CdI₂, AlF₃,
AlCl₃, AlBr₃, AlI₃, Al₂(SO₄)
₃, Al₂(C₂O₄)₃, Al (CH₃COCHCO
CH₃)₃, Al (NO₃)₃, AlPO₄, GeCl
₄, GeBr₄, GeI₄, Sn (OCOCH₃)₄,
Sn (SO₄)₂, SnF₄, SnCl₄, SnB
r₄, SnI₄And the like. Acid treatment impure surface
In addition to materials, the crystal structure of Al, Fe, Mg, etc.
Some or all of the ONs can be eluted.

The acid used in the acid treatment is preferably selected from hydrochloric acid, sulfuric acid, nitric acid, oxalic acid, phosphoric acid and acetic acid. The salt and the acid used for the treatment may be two or more. When the salt treatment and the acid treatment are combined, there are a method of performing the salt treatment and then performing the acid treatment, a method of performing the acid treatment and then performing the salt treatment, and a method of simultaneously performing the salt treatment and the acid treatment.

The conditions for treatment with salts and acids are not particularly limited, but usually the concentration of salts and acids is 0.1 to 3
0% by weight, treatment temperature is from room temperature to boiling point, treatment time is from 5 minutes to
It is preferable to select the condition for 24 hours and to elute at least a part of at least one compound contained in the ion-exchange layered silicate. Further, salts and acids are generally used in an aqueous solution.

In the present invention, the above-mentioned salt treatment and / or acid treatment is preferably performed, but shape control may be performed by pulverization or granulation before, during, or after the treatment. Further, a chemical treatment such as an alkali treatment or an organic substance treatment may be used in combination.
These ion-exchange layered silicates usually contain adsorbed water and interlayer water. In the present invention, it is preferable to remove these adsorbed water and interlayer water to use as component (B).

Here, the adsorbed water is water adsorbed on the surface of the ion-exchangeable layered silicate compound particles or the crystal fracture surface, and the interlayer water is water existing between the layers of the crystals. In the present invention, these adsorbed water and / or interlayer water can be removed by heat treatment before use. The method for heat treatment of the adsorbed water and interlayer water of the ion-exchange layered silicate is not particularly limited, and methods such as heat dehydration, heat dehydration under gas flow, heat dehydration under reduced pressure, and azeotropic dehydration with an organic solvent are used. Can be The temperature at the time of heating cannot be specified unconditionally because it depends on the type of ion-exchanged layered silicate and interlayer ions. Temperature conditions (for example, 800 ° C. or higher, depending on the heating time)
Is not preferred. Further, a heat dehydration method for forming a crosslinked structure such as heating under air flow is not preferable because the polymerization activity of the catalyst is reduced. The heating time is at least 0.5 hour, preferably at least 1 hour. At that time, the water content of the component (B) after the removal was 200 ° C., pressure 1 m
The water content after dehydration for 2 hours under the condition of
In terms of weight%, it is preferably at most 3% by weight, preferably at most 1% by weight.

As described above, in the present invention, particularly preferred as the component (B) is a salt treatment and / or
Or the water content obtained by performing the acid treatment is 1% by weight.
The following are ion-exchangeable layered silicates. As the component (B), it is preferable to use spherical particles having an average particle diameter of 5 μm or more. More preferably, spherical particles having an average particle size of 10 μm or more are used. More preferably, the average particle size is 10
Spherical particles having a size of not less than μm and not more than 100 μm are used. The average particle size referred to here is an optical microscope photograph of the particles (100 times magnification).
Is represented by a number average particle diameter calculated by image processing. As the component (B), a natural product or a commercially available product may be used as it is as long as the shape of the particle is spherical, or a component in which the shape and the particle size of the particle are controlled by particle size, particle size, fractionation, or the like may be used. You may.

The granulation method used here includes, for example, stirring granulation, spray granulation, tumbling granulation, briquetting, compacting, extrusion granulation, fluidized bed granulation, and emulsion granulation. Examples thereof include a submerged granulation method and a compression molding granulation method, but are not particularly limited as long as the component (B) can be granulated. The granulation method is preferably a stirring granulation method, a spray granulation method, a tumbling granulation method, or a fluidized bed granulation method, and particularly preferably a stirring granulation method or a spray granulation method. In addition,
When spray granulation is performed, water or an organic solvent such as methanol, ethanol, chloroform, methylene chloride, pentane, hexane, heptane, toluene and xylene is used as a dispersion medium for the raw material slurry. Preferably, water is used as the dispersion medium. The concentration of the raw material slurry liquid component (B) in the spray granulation for obtaining spherical particles is 0.1 to 70%, preferably 1 to 50%, particularly preferably 5 to 30%. The inlet temperature of the hot air in the spray granulation for obtaining spherical particles varies depending on the dispersion medium, but is 80 to 260 ° C, preferably 100 to 220 ° C in the case of water.

In the granulation, an organic substance, an inorganic solvent, an inorganic salt, and various binders may be used. Examples of the binder used include sugar, dextrose, corn syrup, gelatin, glue, carboxymethyl celluloses, polyvinyl alcohol, water glass, magnesium chloride, aluminum sulfate, aluminum chloride, magnesium sulfate, alcohols, glycol, starch, casein,
Latex, polyethylene glycol, polyethylene oxide, tar, pitch, alumina sol, silica gel,
Gum arabic, sodium alginate and the like can be mentioned.

The spherical particles obtained as described above preferably have a compressive breaking strength of 0.2 MPa or more in order to suppress crushing and fine powder in the polymerization step. In the case of such a particle strength, the effect of improving the particle properties is effectively exhibited, particularly when prepolymerization is performed.

Component (C) Component (C) is an organoaluminum compound. Organic aluminum compounds used as component (C) in the present invention, the compound represented by formula ^{_{(AlR 4 n X 3-n}} ) m is appropriate. In the present invention, it goes without saying that the compounds represented by this formula can be used alone, in combination of two or more kinds. This use is possible not only at the time of catalyst preparation but also at the time of preliminary polymerization or polymerization. In this formula, R ⁴ represents a hydrocarbon group having 1 to 20 carbon atoms, and X represents a halogen, hydrogen, an alkoxy group, or an amino group. n is an integer of 1-3 and m is an integer of 1-2. R ⁴ is preferably an alkyl group, and X represents chlorine when it is halogen, and has 1 carbon atom when it is an alkoxy group.
When the alkoxy group having from 8 to 8 is an amino group, it has 1 to 1 carbon atoms.
Eight amino groups are preferred. Therefore, specific examples of preferred compounds include trimethylaluminum, triethylaluminum, trinormal propyl aluminum, trinormal butyl aluminum, triisobutyl aluminum, trinormal hexyl aluminum, trinormal octyl aluminum, trinormal decyl aluminum, diethyl aluminum chloride, diethyl aluminum chloride, and diethyl aluminum Aluminum sesquichloride, diethylaluminum hydride, diethylaluminum ethoxide, diethylaluminum dimethylamide, diisobutylaluminum hydride, diisobutylaluminum chloride and the like can be mentioned. Among these, preferred compounds are m
= 1 and n = 3 are trialkylaluminum and dialkylaluminum hydrides. Further preferred compounds are trialkylaluminum R ⁴ is 1 to 8 carbon atoms.

Formation of Catalyst As the catalyst used for producing the crystalline propylene / α-olefin random copolymer (1) of the present invention, the above-mentioned components (A) and (B) and, if necessary, It can be prepared by contacting the catalyst comprising the component (C) to be used inside or outside the polymerization tank in the presence or absence of the monomer to be polymerized.
Further, the catalyst may be one obtained by performing prepolymerization in the presence of an olefin. The olefin used for the prepolymerization includes propylene, ethylene, 1-butene, 3
-Methylbutene-1, styrene, divinylbenzene and the like are used, but a mixture of these with other olefins may be used. The components (A), (B) and (C) used in the preparation of the above catalyst can be used in any ratio.

(Ii) Polymerization The polymerization of the crystalline propylene / α-olefin random copolymer (1) used in the present invention is carried out by starting from the component (A), the component (B) and, if necessary, the component (C). The catalyst is mixed and contacted with propylene and ethylene or an α-olefin having 4 to 20 carbon atoms. The amount ratio of each monomer in the reaction system does not need to be constant over time, and it is convenient to supply each monomer at a constant mixing ratio, and to change the mixing ratio of the supplied monomers over time. Is also possible. Further, any of the monomers can be dividedly added in consideration of the copolymerization reaction ratio.

As the polymerization mode, any mode can be adopted as long as the catalyst component and each monomer are in efficient contact with each other. Specifically, a slurry method using an inert solvent, a bulk method using propylene as a solvent without substantially using an inert solvent, a solution method, or substantially converting each monomer into a substantially gaseous state without using a substantially liquid solvent A keeping gas phase method can be employed. Either continuous polymerization or batch polymerization may be used. In the case of slurry polymerization, a single or a mixture of saturated aliphatic or aromatic hydrocarbons such as hexane, heptane, pentane, cyclohexane, benzene, and toluene can be used as a polymerization solvent.

The polymerization conditions are as follows.
The temperature is 60 ° C., preferably 0 ° C. to 150 ° C. At that time, hydrogen can be used as a molecular weight regulator in an auxiliary manner. Further, the polymerization pressure is 0 to 90 kg / cm ² · G, preferably 0 to 60 kg / cm ² · G, particularly preferably 1 to 60 kg / cm ² · G.
It is 50 kg / cm ² · G.

2. Alicyclic hydrocarbon resin Examples of the alicyclic hydrocarbon resin used in the present invention include:
Examples include petroleum resins, terpene resins, rosin resins, cumarone indene resins, and hydrogenated derivatives thereof. Among these, those having no polar group or resins having a hydrogenation ratio of 95% or more by adding hydrogen are preferable. Further preferred resins are petroleum resins or hydrogenated derivatives of petroleum resins, and examples of the petroleum resins include commercially available products such as Alcon manufactured by Arakawa Chemical Industry Co., Ltd. and Escolets manufactured by Tonex Corporation.

The softening point of the alicyclic hydrocarbon resin is 110
C. or higher, preferably 115 ° C.
The temperature is more preferably 125 ° C. or more. If the softening point of the alicyclic hydrocarbon resin is lower than 110 ° C., the film becomes sticky or becomes cloudy due to a change with time.

3. Other components As long as the effects of the present invention are not impaired, an antioxidant, an antistatic agent, a neutralizer, a nucleating agent, a slip agent, and the like can be added.From the viewpoint of ensuring transparency, an antiblocking agent is It is preferable not to use it. Further, within the range not impairing the effects of the present invention, propylene / butene-1 copolymer, polybutene-
1. Known shrinkage property improving components such as linear low density polyethylene may be added.

4. Resin composition Crystalline propylene / α-olefin random copolymer (1) in the resin composition used as the intermediate layer (I) in the present invention
The mixing ratio of the alicyclic hydrocarbon resin to the crystalline propylene / α-olefin random copolymer (1) is 50 to 95.
% By weight, preferably 60 to 90% by weight, more preferably 70 to 85% by weight, and alicyclic hydrocarbon resin in 5 to 50% by weight, preferably 10 to 40% by weight, more preferably 15 to 30% by weight. is there. The crystalline propylene / α-olefin random copolymer (1) in the resin composition has 95
If the content is more than 5% by weight (the content of the alicyclic hydrocarbon resin is less than 5% by weight), the shrinkage property deteriorates. On the other hand, when the crystalline propylene / α-olefin random copolymer (1) is less than 50% by weight (when the alicyclic hydrocarbon resin exceeds 50% by weight), the specific gravity often exceeds 0.94. In addition, the moldability of the film deteriorates, and the resulting label film becomes sticky.

[II] Surface layer (II) Crystalline propylene / α-olefin random copolymer (2) (1) Property (d): MFR MFR (230 ° C., 2.16 kg) of the crystalline propylene / α-olefin random copolymer (2) used in the present invention
Load) is 0.5 to 50 g / 10 min, preferably 1.0
~ 20g / 10min, more preferably 1.0 ~ 10g /
It is 10 minutes, particularly preferably 1.0 to 5.0 g / 10 minutes. If the MFR is less than 0.5 g / 10 minutes, the extrusion characteristics may be deteriorated and the productivity may be reduced.
If the time exceeds 10 minutes, the moldability deteriorates and thickness unevenness occurs.

[0055] (2) Characteristics (e): The main melting peak temperature obtained by DSC of DSC in the obtained primary melting peak temperature _(T P) crystalline propylene · alpha-olefin random copolymer used in the present invention (2) (T _P ) is 100 to 150 ° C., preferably 100
To 130 ° C, more preferably 100 to 125 ° C. If the melting peak temperature (T _P ) is less than 100 ° C., the unstretched sheet is difficult to be cooled and solidified, and film forming becomes difficult.

(3) Constituents of the crystalline propylene / α-olefin random copolymer (2) α of the crystalline propylene / α-olefin random copolymer (2) used in the present invention which is randomly copolymerized with propylene -As the olefin, ethylene or a carbon number of 4 to
20 α-olefins, ethylene, butene
It is preferable to use 1, hexene-1, octene-1, and the like, and ethylene is particularly preferable. The α-olefin content in the random copolymer is usually about 2.0 to 30% by weight as long as the α-olefin is ethylene. It is about 10% by weight, preferably about 2.0 to 6.0% by weight. Further, as long as the above properties (d) to (e) are satisfied, the crystalline propylene / α-olefin random copolymer (2) may be a mixture of two or more kinds. When the surface layer (II) is laminated on both surfaces of the intermediate layer (I), even if the same crystalline propylene / α-olefin random copolymer is laminated, different crystalline propylene / α-olefin random copolymers may be used. Polymers may be laminated.

(4) Method for producing crystalline propylene / α-olefin random copolymer (2) The crystalline propylene / α-olefin random copolymer (2) used in the present invention has the above properties (d) to (d). If e) is satisfied, the crystalline propylene
It may be an α-olefin random copolymer. Preferably, like the above-mentioned crystalline propylene / α-olefin random copolymer (1), a crystalline propylene / α-olefin random copolymer polymerized using a metallocene catalyst is used.

2. Anti-blocking agent The anti-blocking agent used in the present invention is not particularly limited, for example, silica, cross-linked polymethyl methacrylate,
Known materials such as silicone particles and calcium carbonate can be used.

The volume average particle diameter of the antiblocking agent must be 1.0 to 10 μm, and preferably 1.5 to 5.0 μm. When the volume average particle diameter of the anti-blocking agent is less than 1.0 μm, the transparency of the film is good, but the blocking property and the slip property deteriorate. On the other hand, when the volume average particle size exceeds 10 μm,
As the transparency of the film is deteriorated, problems such as easy printing omission during label printing and white powder generation due to falling off of the anti-blocking agent are likely to occur.

3. Other Components An antioxidant, an antistatic agent, a neutralizing agent, a nucleating agent, a slip agent and the like can be added as long as the effects of the present invention are not impaired. Further, within the range not impairing the effects of the present invention, for the purpose of further improving the shrinkage properties, excluding alicyclic hydrocarbon resins such as propylene / butene-1 copolymer, polybutene-1, and linear low-density polyethylene. Known shrinkage property improving components can be added. Further, addition of 1 to 10 parts by weight of a maleic anhydride-modified polypropylene, for example, Umex 1001 manufactured by Sanyo Chemical Co., Ltd. to 100 parts by weight of the crystalline propylene / α-olefin random copolymer (2) may be carried out at the time of stretching. This is preferable because the generation of voids due to the antiblocking agent is prevented, and the transparency and the falling resistance of the antiblocking agent are further improved.

4. Resin composition In the resin composition used as the surface layer (II) in the present invention, the blending ratio of the crystalline propylene / α-olefin random copolymer (2) and the antiblocking agent is determined by the crystalline propylene / α-olefin random copolymer. Coalescing (2) 100
Antiblocking agent 0.05-1.
0 parts by weight, preferably 0.2 to 1.0 parts by weight, more preferably 0.2 to 0.5 parts by weight. When the content of the anti-blocking agent in the composition is less than 0.05 part by weight, the transparency of the film is good, but the blocking and slip properties are deteriorated. On the other hand, when the amount of the antiblocking agent exceeds 1.0 part by weight, the transparency is deteriorated.

[III] Method for Forming Laminated Film for Shrink Label The laminated film for a heat-shrinkable polypropylene shrink label of the present invention comprises the above-mentioned intermediate layer (I) and surface layer (I).
Although I) is used by lamination, a known method such as a melt co-extrusion method is used as a method for forming a laminated film. In addition, the film can be stretched by a known method such as an inflation method or a flat stretching method. In the present invention, a flat stretching method, particularly a tenter type uniaxial stretching method is used. Is preferred. After the melt co-extrusion by the above-mentioned molding method, the film is stretched at least two times, preferably four times or more in at least one axial direction by a known method to produce the laminated film for shrink labels of the present invention. The stretching direction may be uniaxial or more, but it is preferable to uniaxially stretch only in a direction perpendicular to the film flow direction. On the other hand, if the stretching ratio is less than 2, a sufficient shrinkage cannot be obtained. Further, for the purpose of improving the shrinkage, it is preferable to stretch at as low a temperature as possible. Particularly, when there is a step of applying preheating to the unstretched sheet, the preheating temperature is set as low as possible within a range in which molding is possible. Is preferred.

[IV] Laminated Film for Shrink Label The thickness of the laminated film for a shrink label of the present invention is not particularly limited, but is 100 μm or less, preferably 30 to 80 μm. In the laminated film for a shrink label of the present invention, the sum of the thicknesses of the surface layer (II) is 1 to 50%, preferably 3 to 30%, more preferably 5 to 10% of the total film thickness. If the sum of the thicknesses of the surface layer (II) exceeds 50% of the total film thickness, the shrinkage characteristics, particularly the low-temperature shrinkage characteristics, deteriorate. On the other hand, if the sum of the thicknesses of the surface layer (II) is less than 1% of the total film thickness, the unstretched sheet tends to stick to the cooling roll during extrusion of the unstretched sheet, and the moldability deteriorates.

The specific gravity of the laminated film for a shrink label of the present invention is 0.94 or less, and the specific gravity is 0.9.
If it exceeds 4, the specific gravity increases when the film is subjected to secondary processing such as printing, so that the efficiency of floating separation from a PET bottle or the like by water deteriorates.

Further, the shrinkage ratio of the laminated film for shrink labels of the present invention in the main shrinkage direction at 40 ° C. for 7 days is less than 3%, preferably less than 2%, more preferably less than 1%. When the shrinkage ratio in the main shrinkage direction is 3% or more, shrinkage is apt to occur during transport and storage of the film, and the film is tightly tightened and thickened, resulting in a significant reduction in commercial value.

The shrinkage ratio and specific gravity of the laminated film for a shrink label of the present invention satisfy the following relational expressions. Formula: S ₈₀ > 251d-215 Formula: S ₉₀ > 531d-462 Formula: S ₁₀₀ > 627d-541 (However, S ₈₀ , S ₉₀ , and S ₁₀₀ are each 80 ° C.
The shrinkage ratio (%) in the main shrinkage direction when heated in a hot water bath at 90 ° C. and 100 ° C. for 10 seconds, and d is the specific gravity of the laminated film for shrink labels. Those that do not satisfy the above formulas (1) to (4) have a poor balance between shrinkage and specific gravity, and deteriorate either packaging suitability or recycling suitability.

[V] Heat Shrinkable Shrink Label The heat shrinkable shrink label of the present invention can be obtained by processing the above-described laminated film for shrink label into a cylindrical shape. The processing method is not particularly limited, and a known method can be used. For example, a shrink label can be obtained by applying a center seal to a flat laminated film for a shrink label such that the main shrinkage direction of the film is the circumferential direction. Examples of the center sealing method include, but are not limited to, sealing by applying an organic solvent, sealing by applying an adhesive, and heat sealing. In addition, printing may be performed before processing the laminated film for a shrink label into a cylindrical shape.

The heat-shrinkable shrink label obtained from the laminated film for a shrink label of the present invention has a specific gravity of less than 1.0 even after secondary processing such as printing, and thus contributes to weight reduction of various containers. In addition, floating separation with water from a PET bottle is possible. Furthermore, compared to the conventional polypropylene shrink label, the shrink property, especially the low temperature shrink property, is excellent, so that the shrink packaging suitability is excellent and the container packaging with beautiful appearance can be realized.

[VI] Container Mounted with Heat-Shrinkable Shrink Label The heat-shrinkable shrink label of the present invention is mounted on various containers and heat-shrinkable to obtain a container equipped with the heat-shrinkable shrink label. . The container to be attached is not particularly limited, and examples include a PET bottle, a polypropylene bottle, a bottle container, and a lunch container.

[0070]

EXAMPLES The present invention will be specifically described with reference to examples below, but the present invention is not limited to these examples. In addition, the evaluation method used in the Examples and Comparative Examples,
The method for forming the laminated film for labels is as follows.

(1) Suitability for packaging: The laminated film for shrink labels was cut into a length of 22.5 cm in the main shrink direction and a length of 20 cm in a direction perpendicular to the main shrink direction. A cylindrical shrink label was obtained by rounding into a cylindrical shape having a circumferential length of 21.5 cm so that the main shrinkage direction was the circumferential direction, and heat-sealing the overlapping portion. One end of the obtained label was covered so that the lower end of a commercially available PET bottle (500 ml, Kirin Beverage Suppli) was aligned. 500 ml of water (25 ° C.) was placed in a PET bottle with a label attached, and the cap was capped, then immersed in a water tank adjusted to 90 ° C. for 5 seconds. After 5 seconds, immediately remove from the water tank at 90 ° C,
Label wrapping was performed by immersing in a separately prepared water bath at 25 ° C. for 1 minute or more. 15.7 cm from the bottom of the PET bottle after label packaging (top position of the label on a commercially available PET bottle. Perimeter: 18.0 cm, shrinkage: 16.3%)
The state of close contact of the label was examined, and those that were completely adhered were evaluated as good, and those that were insufficiently adhered were evaluated as defective.

(2) Specific gravity: Measured by a density gradient tube method using a sample after label packaging in a PET bottle in accordance with JIS K-7112.

(3) Separability: The film after label packaging in a PET bottle was cut into a square having a side of 10 cm and further cut into a side of 1 cm to obtain a film piece. The film pieces were placed in a 1-liter beaker previously containing 800 ml of 25 ° C. distilled water. A rotor having a length of 3 cm was put in a beaker, and the number of revolutions was set with a magnetic stirrer so that the film pieces were dispersed throughout the beaker. In addition,
The evaluation of the separability was performed at the same rotation speed for all the samples.
After rotating the magnetic stirrer for 20 seconds, the rotation was stopped and the time required for all the film pieces to rise to near the water surface was measured. This operation was repeated 10 times per sample, and the average value excluding the maximum value and the minimum value was used as a measure of separability. Until the film piece is near the water surface,
The shorter the time required to float, the better the separation.

(4) Formability: During film formation, the ease of peeling of the unstretched sheet formed by melt extrusion from a T-die from a cooling roll (mirror finish) was evaluated according to the following criteria. ：: easily peeled off, no problem in molding. Δ: Difficult to peel, but no problem in molding. ×: Difficult to peel off and difficult to mold.

(5) Appearance: The appearance of the formed film was evaluated according to the following criteria. ：: Uniformly stretched. ×: The film was partially unevenly stretched, and surface cracks were observed.

(6) MFR: MFR was measured in accordance with JIS K-6758 (condition 230 ° C., load 2.16 kg).

[0077] (7) _{T P} and _{T 50:} using Seiko Co. differential scanning calorimeter (DSC), a sample (crystalline propylene · alpha-olefin random copolymer) 5.0 m
g, hold at 200 ° C for 5 minutes, and then
Cooled at 0 ° C. / min cooling speed is further melted at 10 ° C. / min temperature increase speed to obtain a heat of fusion curve, the heat of fusion curve obtained was determined T _P and T _50.

(8) Softening point temperature: JIS K-2207
It measured according to.

(9) Heat shrinkage rate: 4
After aging at 0 ° C for 24 hours, 10cm x 10c
m was cut out so that one side thereof was parallel to the film flow direction, and this was immersed in a water bath heated to a predetermined temperature for 10 seconds. Immediately after the elapse of 10 seconds, the film was immersed in a separately prepared water bath at 25 ° C. for 20 seconds, and then the lengths of the film in the flow direction and in the orthogonal direction were measured to determine the heat shrinkage. The value in the main shrinkage direction was defined as the heat shrinkage rate.

(10) Blocking property (unit: g / 10)
cm ² ): The corona-treated surfaces of a film having a width of 2 cm and a length of 15 cm are overlapped with each other over a length of 5 cm, and 100 g / c.
m ² under a load of 40 ° C. for 24 hours,
After removing the load and sufficiently adjusting the temperature to 23 ° C., the force required for shearing and peeling the sample was measured at a speed of 200 mm / min using a tensile tester. The smaller the value, the better.

(11) Haze: Measured according to JIS K-7105 and used as a measure of transparency. The smaller the value, the better.

(12) Slipperiness: According to ASTM-D1894, the coefficient of static friction (μs) and the coefficient of dynamic friction (μ
d) was measured. The smaller the value, the better.

(13) Natural shrinkage: After stretching the stretched film at 40 ° C. for 24 hours, 10 cm × 10
The film was cut into a square having a side of a cm parallel to the direction of film flow and placed in a gear oven at 40 ° C. for 7 days. After standing for 7 days, the length of each of the film in the flow direction and the orthogonal direction was measured, and the natural shrinkage was determined. The value of the main shrinkage direction was defined as the natural shrinkage ratio.

(14) Forming of Film (i) Forming of Unstretched Sheet The resin composition for the intermediate layer (I) was obtained from a 75 mm single screw extruder and from a 30 mm single screw extruder and a 20 mm single screw extruder. Each of the resin compositions for both surface layers (II) was melt-coextruded at 240 ° C. by a T-die method so as to have a predetermined thickness, and cooled and solidified by a cooling roll at 15 ° C. to obtain a thickness of 300 μm. Was obtained.

(Ii) Formation of stretched film The unstretched sheet obtained above was introduced into a tenter furnace, and 6.
It is possible to stretch 5 times and at the lowest temperature
The film was preheated for 2 seconds and stretched 6.5 times in the width direction at a temperature equivalent to the preheating temperature over 30 seconds. Then, while relaxing 7.5% in the width direction in the tenter furnace,
Annealing was performed for 0 second to obtain a heat-shrinkable shrink label film having a draw ratio of 6 and a thickness of 50 μm.

(15) Production of crystalline propylene / α-olefin random copolymer (i) Dimethylsilylenebis [1- {2-methyl-4-
(4-Chlorophenyl) -4H-azulenyl}] Synthesis of Racemic Form of Zirconium Dichloride (a) Synthesis of Racemic / Meso Mixture 1.84 g of 1-bromo-4-chlorobenzene (9.6 m
mol) of n-hexane (10 ml) and diethyl ether (10 ml) at -78 ° C in 11.7 ml of a pentane solution of t-butyllithium (1.64 M) (19.
2 mmol) was added dropwise. The resulting solution was treated at -5 ° C with 1.
After stirring for 5 hours, 1.2 g of 2-methylazulene was added to the solution.
(8.6 mmol) was added to carry out the reaction. The reaction solution was stirred for 1.5 hours while gradually returning to room temperature.
Thereafter, the reaction solution was cooled to 0 ° C., and 15 μl (0.19 mmol) of 1-methylimidazole was added.
0.52 ml of dichlorodimethylsilane (4.3 mmo
l) was added. After stirring the reaction solution at room temperature for 1.5 hours,
The reaction was stopped by adding dilute hydrochloric acid, the separated organic phase was concentrated under reduced pressure, dichloromethane was added, and the mixture was dried over magnesium sulfate. After evaporating the solvent under reduced pressure, the residue was purified by silica gel column chromatography to obtain 2.1 g of an amorphous solid.

Next, 1.27 g of the above reaction product was dissolved in 15 ml of diethyl ether.
1. n-hexane solution of butyllithium (1.66 M)
8 ml (4.5 mmol) were added dropwise. After completion of the dropwise addition, the reaction solution was stirred for 12 hours while gradually returning to room temperature.
After distilling off the solvent under reduced pressure, 5 ml of a mixed solvent of toluene and diethyl ether (40: 1) was added, and the mixture was cooled to -78 ° C, and 0.53 g of zirconium tetrachloride (2.3 g) was added thereto.
mmol) was added. Then, immediately return to room temperature,
The reaction was carried out by stirring at room temperature for 4 hours. The obtained reaction solution was filtered over celite, and the solid separated by filtration was mixed with 3 ml of toluene.
And washed. The collected solid was extracted with dichloromethane, the solvent was distilled off from the extract, and dimethylsilylenebis [1- {2-methyl-4- (4-chlorophenyl)-
906 mg (yield 56%) of a racemic / meso mixture of [4H-azulenyl}] zirconium dichloride was obtained.

(B) Purification of racemic form Further, 900 mg of the above-mentioned racemic / meso mixture was dissolved in 20 ml of dichloromethane, and a 100 W high-pressure mercury lamp was used.
By irradiating for 0 minutes, the ratio of the racemate was increased, and then the insoluble matter was removed by filtration, and the collected filtrate was concentrated to dryness. Then, the obtained solid component was stirred with 22 ml of toluene, and after standing, the supernatant was removed.
This was repeated twice, and the remaining solid component was dried to obtain 275 mg of a racemic dimethylsilylenebis [1- {2-methyl-4- (4-chlorophenyl) -4H-azulenyl}] zirconium dichloride.

(Ii) Chemical treatment of clay mineral 218.1 g of sulfuric acid (96%) and magnesium sulfate 13
A commercially available montmorillonite (Kunimine Kogyo, Knipia F) 20 was added to an aqueous solution obtained by mixing 0.4 g of the mixture with 909 ml of demineralized water.
0.03 g was dispersed and stirred at 100 ° C. for 2 hours. This montmorillonite water slurry was used to obtain a solid concentration of 12%.
And subjected to spray granulation with a spray drier to obtain particles. Thereafter, the particles were dried under reduced pressure at 200 ° C. for 2 hours.

(Iii) Preparation of Catalyst Component After thoroughly replacing the inside of a 1-liter stirred autoclave with propylene, 230 ml of dehydrated and deoxygenated heptane was prepared.
Was introduced, and the temperature in the system was maintained at 40 ° C. Here, 10 g of chemically treated clay slurried with toluene was added. Further, in a separate container, 0.15 mmol of racemic dimethylsilylenebis [1- {2-methyl-4- (4-chlorophenyl) -4H-azulenyl}] zirconium dichloride and 1.5 mmol of triisobutylaluminum mixed under toluene. Was added. Where propylene is 1
Introduced at a rate of 0 g / h for 120 minutes, and then polymerization was continued for 120 minutes. Further, the solvent was removed and dried under nitrogen to obtain a solid catalyst component. This solid catalyst component is 1 g of a solid component.
Per 1.9 g of polypropylene.

(Iv) Polymerization After sufficiently replacing propylene in the stirred autoclave having an internal volume of 200 l, liquefied propylene
5 kg were introduced. To this were added 500 ml (0.12 mol) of a triisobutylaluminum / n-heptane solution, 2.0 kg of ethylene, and 3.5 l of hydrogen (as a standard state volume), and the internal temperature was maintained at 30 ° C. Then, 1.45 g of the solid catalyst component was injected with argon to start polymerization, and the temperature was raised to 70 ° C. over 30 minutes, and the temperature was maintained for 1 hour. Here, 100 ml of ethanol was added to stop the reaction. Purging residual gas, propylene / ethylene random copolymer (PP) 1 having the following physical properties
3.7 kg were obtained. The above polymerization was repeated to obtain a required amount to obtain a sample. MFR: 2.58 g / 10 minutes, ethylene content: 3.42
_{Wt%, T P: 122.7 ℃,} T 50: 113 ℃.

Using a conventional Ziegler-Natta catalyst,
A propylene / ethylene random copolymer (PP) was produced. The obtained propylene / ethylene random copolymer had the following physical properties. MFR: 2.30 g / 10 minutes, ethylene content: 3.60
_{Wt%, T P: 138.3 ℃,} T 50: 130 ℃.

Further, as PP, MFR: 2.4 g /
A propylene homopolymer (FL6CK, manufactured by Nippon Polychem Co., Ltd.) for 10 minutes and T _P : 160.3 ° C. was used.

Example 1 75% by weight of the above-obtained PP powder, Escolez E5320 manufactured by Tonex Corporation (softening point temperature: 125)
C) 0.05 parts by weight of calcium stearate, 10100.1 parts by weight of Irganox, irgafos 168 based on 100 parts by weight of a resin composition consisting of 25% by weight.
After mixing 0.1 part by weight with a Henschel mixer, 50 parts
The mixture was granulated by a single-mm extruder to obtain a resin composition pellet for the intermediate layer (I). Further, 0.05 parts by weight of calcium stearate, 0.1 parts by weight of Irganox 1010, and Irgafos 168 are based on 100 parts by weight of PP powder.
0.1 part by weight and 0.2 part by weight of synthetic silica having a volume average particle size of 2.5 μm as an antiblocking agent were mixed with a Henschel mixer, and then granulated with a 50 mm single screw extruder to form a surface layer (II). A resin composition pellet was obtained. Using the resin composition pellets described above, a laminated film for a shrink label was formed by the method described above. The total thickness of the obtained film is 50 μm, and the thickness of the intermediate layer (I) is 44 μm.
m and the thickness of the surface layer (II) were 3 μm on both sides. The minimum preheatable temperature for forming the film is 60
° C. Table 1 shows the evaluation results of the obtained films.

Example 2 PP was used as the base PP of the resin composition for the surface layer (II).
A laminated film for a shrink label was formed in the same manner as in Example 1 except for using. The minimum preheatable temperature at which the film was formed was 60 ° C. Table 1 shows the evaluation results of the obtained films.

Comparative Example 1 A laminated film for a shrink label was formed in the same manner as in Example 1 except that the resin composition for the surface layer (II) was the same as the resin composition for the intermediate layer (I). . The minimum preheatable temperature at which the film was formed was 60 ° C.
The evaluation results of the obtained film are shown in Table 1. As compared with the examples, the moldability was worse, and the anti-blocking property and the slip property were worse.

Comparative Example 2 The procedure of Example 1 was repeated, except that the base PP of the resin composition for the intermediate layer (I) was changed to PP, and the base PP of the resin composition for the surface layer (II) was changed to PP. A laminated film for a shrink label was formed. The minimum preheatable temperature at which the film was formed was 80 ° C. The evaluation results of the obtained film are shown in Table 1. The suitability for packaging was worse than that of the examples.

Comparative Example 3 A laminated film for a shrink label was formed in the same manner as in Example 1 except that no antiblocking agent was added to the resin composition for the surface layer (II). The minimum preheatable temperature at which the film was formed was 60 ° C. The evaluation results of the obtained film are shown in Table 1. The anti-blocking property and the slip property were worse than those of the examples.

Comparative Example 4 0.05 parts by weight of calcium stearate was added to 100 parts by weight of a resin composition consisting of 50% by weight of PP powder and 50% by weight of Escolets E5320 (softening point temperature: 125 ° C.) manufactured by Tonex Corporation. Irganox 101
0 parts by weight of 0.1 and 0.1 parts by weight of Irgafos 168 were mixed with a Henschel mixer, and then granulated with a 50 mm single screw extruder to obtain a resin composition pellet for the intermediate layer (I). Further, 0.05 parts by weight of calcium stearate, Irganox 1 and 100 parts by weight of PP powder were used.
010, 0.1 parts by weight of Irgafos 168, and 0.2 parts by weight of synthetic silica having a volume average particle size of 2.5 μm as an antiblocking agent were mixed with a Henschel mixer, and then mixed with a 50 mm single screw extruder. The resultant was granulated to obtain a resin composition pellet for the surface layer (II). Using the resin composition pellets described above, a laminated film for a shrink label was formed by the method described above. The total thickness of the obtained film was 50 μm, the thickness of the intermediate layer (I) was 44 μm, and the thickness of the surface layer (II) was 3 μm on both sides. The minimum preheatable temperature at which the film was formed was 60 ° C. The evaluation results of the obtained film are shown in Table 1. The specific gravity increased, the moldability slightly deteriorated, and the separability deteriorated as compared with the examples.

Comparative Example 5 A laminated film for a shrink label was formed in the same manner as in Example 1 except that the thickness of the intermediate layer (I) was changed to 20 μm and the thickness of the surface layer (II) was changed to 15 μm on both sides. . The minimum preheating temperature at which the film can be formed is 70 ° C.
Met. The evaluation results of the obtained film are shown in Table 1. The appearance was worse than that of the examples, and the suitability for packaging was worse.

[0101]

[Table 1]

[0102]

The heat-shrinkable polypropylene-based shrink label laminated film of the present invention has improved heat shrinkage, especially low-temperature shrinkage, and has a low specific gravity to improve the balance between packaging suitability and recycling efficiency. It is suitable for use as a shrink label for containers because of its excellent balance between transparency and transparency, anti-blocking properties and slipperiness.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) B65D 65/40 BSM B65D 65/40 BSMD BSQ BSSQD C08L 23/16 C08L 23/16 G09F 3/04 G09F 3 / 04 C // (C08L 23/16 (C08L 23/16 45:00) 45:00) F term (reference) 3E086 AB01 AC34 AD04 AD16 BA04 BA15 BA33 BB55 BB67 BB87 BB90 4F100 AK02A AK07 AK66A AK66B AK66C AL04A AL04B AL05A AL05B AL05C BA02 BA03 BA06 BA07 BA10B BA10C BA25 CA19 DE01B DE01C EH20 EH202 GB90 JA04A JA05A JA06A JA11A JA11B JA11C JK08 JK16 JN01 YY00A YY00B YY00C 4J002 AF022 BA002 BA012 BB141 BB151 BK002 CE002 GF00GG01

Claims (6)

[Claims] 1. A surface layer on one or both sides of the intermediate layer (I)
(II) is laminated and extended at least twice in at least one axis direction.
Stretched laminated film, laminated on one or both sides
The thickness of the surface layer (II) is 1 to 1 of the total film thickness.
50%, and the intermediate layer (I) has the following properties (a) to
Crystalline propylene based propylene satisfying (c)
Len / α-olefin random copolymer (1) 50-9
Alicyclic coal having a softening point of 5% by weight or more and 110 ° C or more
5 to 50% by weight of a hydrogenated resin.
And the surface layer (II) satisfies the following properties (d) to (e).
Crystalline propylene mainly composed of propylene
For 100 parts by weight of the fin random copolymer (2),
Anti-blocky having a volume average particle size of 1.0 to 10 μm
Resin composition containing 0.05 to 1.0 parts by weight of
Heat-shrinkable polypropylene shr
Laminated film for link labels. Intermediate layer (I) Characteristics (a): melt flow rate (230 ° C., 2.16
kg load) is 0.5 to 10 g / 10 min. Characteristic (b): Mainly determined by a differential scanning calorimeter (DSC)
Melting peak temperature (T _P) In the range of 100-140 ° C
There is. Characteristic (c): T₅₀≤125 ° C (However, T₅₀Is the crystalline propylene determined by DSC
・ Total heat of fusion of α-olefin random copolymer (1)
Is ΔHm, the heat of fusion calculated from the low temperature side is ΔHm.
This is the temperature (° C.) at which 50% of Hm is reached. ) Surface layer (II) Characteristics (d): melt flow rate (230 ° C, 2.16)
kg load) is 0.5 to 50 g / 10 min. Characteristic (e): Mainly determined by a differential scanning calorimeter (DSC)
Melting peak temperature (T _p) In the range of 100-150 ° C
There is. 2. The crystalline propylene / α-olefin random copolymer (1) and the crystalline propylene / α-olefin
The laminated film for a heat-shrinkable polypropylene shrink label according to claim 1, wherein the olefin random copolymer (2) is a propylene / ethylene random copolymer. 3. The laminated film for a heat-shrinkable polypropylene shrink label according to claim 1, wherein the crystalline propylene / α-olefin random copolymer (1) is a copolymer obtained by polymerization with a metallocene catalyst. . 4. The shrinkage ratio in the main shrinkage direction satisfies the following expression (1), the specific gravity is 0.94 or less, and the shrinkage ratio in the main shrinkage direction at 40 ° C. for 7 days is less than 3%. 4. The laminated film for a heat-shrinkable polypropylene shrink label according to any one of 1 to 3. Formula: S ₈₀ > 251d-215 Formula: S ₉₀ > 531d-462 Formula: S ₁₀₀ > 627d-541 (However, S ₈₀ , S ₉₀ , and S ₁₀₀ are each 80 ° C.
The shrinkage ratio (%) in the main shrinkage direction when heated in a hot water bath at 90 ° C. and 100 ° C. for 10 seconds, and d is the specific gravity of the laminated film for shrink labels. ) 5. A heat-shrinkable label comprising the laminated film for a heat-shrinkable polypropylene shrink label according to claim 1, having a specific gravity of less than 1.0. 6. A container equipped with the heat-shrinkable label according to claim 5.