JPH1129671A - Wrap film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a wrap film good in safety, flexibility, sticking property, cutting property, etc., and suitable for heating with an electronic oven, and a cold or a frozen storage by using a resin composition consisting of a 4- methyl-1-pentene-based polymer with an oil and fat. SOLUTION: This wrap film is formed from a resin composition containing (A) 100 pts.wt. 4 methyl-1-pentene based polymer and (B) 1-15 pt.wt. oil and fat (e.g.; an ester compound of glycerol with stearic acid). By containing an ethylene-α-olefin copolymer having <=0.90 g/cm<3> in the above resin composition, the preventing property of tearing of a film thereof can be improved further. Also, by containing a high pressure polyethylene and a polybutene therein, the melt physical properties of the composition can become easily controllable and impart further sticking property to the film.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wrap film for home use or business use, and more particularly to a film having good safety, flexibility, adhesiveness, cutability, transparency and tear resistance, especially low-temperature flexibility and film-to-film. Alternatively, the present invention relates to a wrap film having good adhesion between a film and a container and suitable for heating, refrigeration, and frozen storage by a microwave oven.

[0002]

2. Description of the Related Art Conventionally, when food is heated by a microwave oven, or when food is refrigerated,
Polyvinylidene chloride (hereinafter, referred to as "PVD
C), polyvinyl chloride (hereinafter also referred to as “PVC”), polyethylene (hereinafter also referred to as “PE”),
A film containing polypropylene (hereinafter, also referred to as “PP”) as a main component is used.

However, since PVDC and PVC have chlorine in their molecular structure, they cause harmful dioxins by incineration after being discarded, and have a serious environmental problem. . Also, PVC
Has a problem that a whitening phenomenon occurs when it comes into contact with boiling hot water. Further, the PVDC-based wrap film formed from PVDC has a problem that the film shrinks greatly when heated, and the film may be torn due to the shrinkage during heating cooking in a microwave oven, for example. Further, the PVDC-based wrap film is apt to be irregularly torn when cut with a "saw blade" on a box storing the film wound up on a paper tube, and is difficult for a user to use. It has become.

Further, a PE-based wrap film formed of PE has a low glass transition temperature and is suitable for use in storage by freezing or refrigeration. However, since it has a low heat-resistant temperature, it can be heated when used in cooking in a microwave oven. There is a problem that holes are easily opened by the oil component. Also,
A wrap film using an ethylene-vinyl acetate copolymer (hereinafter, also referred to as "EVA") can improve mechanical strength and the like, but has a problem of generating a characteristic acetic acid odor. Further, although the PP-based wrap film formed from PP has high heat resistance, it has low low-temperature embrittlement resistance and is not preferable for frozen storage, and also has low adhesiveness, so that it has an adhesive force to a container, Apply to adhesion. further,
The PP-based wrap film is not easily cut by a “saw blade” because of strong tearing. Further, since each of the conventional wrap films described above contains a large amount of a plasticizer, there is also a problem that the plasticizer precipitates on the film surface during use and contaminates food.

In order to solve the above-mentioned various problems, various proposals have been made on wrap films.
For example, JP-A-5-239291 discloses a resin composition obtained by adding a liquid butene polymer having a kinematic viscosity at 100 ° C. of 2 to 5000 cSt to a 4-methyl-1-pentene polymer. The disclosed wrap film is disclosed. JP-A-6-32952 discloses that a 4-methyl-1-pentene-based polymer is
A wrap film formed by molding a resin composition containing a liquid butene-based polymer having a kinematic viscosity at 2 ° C. of 2 to 5000 cSt and a butene-1-based solid polymer is disclosed. Also, JP-A-6-136149 discloses that 4-methyl-
A wrap film comprising a resin composition obtained by adding polybutene and / or a hydrogenated petroleum hydrocarbon resin to a 1-pentene polymer is disclosed. Further, Japanese Patent Application Laid-Open
JP-A-165940 discloses a stretch film having a layer made of a composition obtained by adding a liquid saturated hydrocarbon to a 4-methyl-1-pentene polymer.

[0006] However, 4-
Although the methyl-1-pentene polymer is excellent in heat resistance, it has disadvantages of low low-temperature embrittlement resistance, strong tearing of the obtained film, and poor cuttability. Further, as described in these publications, 4-methyl-
When a large amount of a butene-1 solid polymer is added to a 1-pentene polymer, a good film cannot be formed due to poor compatibility with the 4-methyl-1-pentene polymer, or However, there is a problem that the cutability of the resulting film is not good. In addition, simply adding liquid butene, liquid saturated hydrocarbon, and hydrogenated petroleum hydrocarbon resin to a 4-methyl-1-pentene polymer results in low-temperature embrittlement resistance, transparency, heat resistance, and the like. It was difficult to obtain a well-balanced wrap film with every performance.

For this reason, a wrap film used for packaging and storing foods or for cooking by heating in a microwave oven or the like has low-temperature embrittlement resistance, high transparency, and is stable to hot water. Therefore, it is required to develop a material that can withstand microwave cooking, has excellent adhesiveness to containers, adhesiveness between films (self-adhesiveness), cutability with a saw blade, and high safety to the environment and the human body. I was

[0008] Accordingly, an object of the present invention is to provide a composition having good safety, flexibility, tackiness, cutability, transparency and tear resistance.
In particular, it is an object of the present invention to provide a wrap film having low-temperature flexibility and good adhesiveness between films or between a film and a container, which is suitable for heating, refrigeration, and frozen storage by a microwave oven.

[0009]

The inventors of the present invention have conducted intensive studies and as a result, have found that a wrap film formed from a resin composition containing a specific component in a 4-methyl-1-pentene polymer is obtained. It has been found that the above object can be achieved.

The present invention has been made based on the above findings, and contains 1 to 15 parts by weight of a fat or oil (B) based on 100 parts by weight of a 4-methyl-1-pentene polymer (A). A wrap film characterized by being formed from a resin composition.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION The wrap film of the present invention is a household or business wrap film (packaging film) used for heating foods in a microwave oven or for refrigeration or freezing of foods. Fat (B) 1 with respect to 100 parts by weight of, 4-methyl-1-pentene polymer (A)
It is formed from a resin composition containing up to 15 parts by weight.

The 4-methyl-1-pentene polymer which is the component (A) used in the resin composition according to the present invention is used as a base material (a resin as a main component) of the resin composition. It is. The 4-methyl-1-pentene polymer may be a polymer containing 4-methyl-1-pentene as a main component, for example, a homopolymer of 4-methyl-1-pentene or 4-methyl-1-pentene. And copolymers of -1-pentene with one or two or more α-olefins other than 4-methyl-1-pentene. The 4-methyl-1
As the α-olefin other than -pentene, for example, ethylene, propylene, 1-butene, 1-heptene, 1-
Hexene, 1-octene, 1-decene, 1-dodecene,
C2-C20 α-olefins such as 1-tetrecene, 1-hexadecene, 1-octadecene, and 1-eicosene, and the like, and these α-olefins are contained in a 4-methyl-1-pentene polymer. When it is contained, its content is usually about 1 to 10% by weight. Further, the copolymer may be any of a random copolymer and a block copolymer.

The 4-methyl-1-pentene polymer has an intrinsic viscosity measured at 135 ° C. in a decalin solvent of usually from about 1.0 to 3.0, preferably from 2.0 to 2.0. About 2.5.

The fat or oil which is the component (B) used in the resin composition according to the present invention exerts the effects of the present invention when used together with the component (A). That is, a film having good safety, flexibility, adhesiveness, cuttability, transparency and tear resistance can be obtained by both components.
In particular, the fats and oils are components that can impart low-temperature flexibility of the composition and adhesiveness between films or between a film and a container.

As the above fats and oils, hydrocarbon compounds, glycerin ester compounds and sucrose polyesters are preferably used. Among them, glycerin ester compounds and sucrose polyesters are hardly absorbed by the human body and have low accumulation properties. Therefore, it can be particularly preferably used. Examples of the hydrocarbon compound include liquid paraffin. Examples of the glycerin ester compound include ester compounds of glycerin with fatty acids such as stearic acid, oleic acid, lauric acid, caprylic acid, behenic acid, ricinoleic acid, palmitic acid, myristic acid, and capric acid. No. Examples of the sucrose polyester include ester compounds of sucrose with fatty acids such as stearic acid, palmitic acid, myristic acid, oleic acid, lauric acid, behenic acid, and erucic acid.

The content of the above fats and oils is 4-methyl-1
-1 to 15 parts by weight based on 100 parts by weight of the pentene polymer [component (A)]. When the content of the fat or oil is less than 1 part by weight, low-temperature flexibility or adhesiveness between films or between a film and a container cannot be imparted. The components bleed out and become sticky. In particular, the content of the fat or oil is preferably 1 to 10 parts by weight with respect to 100 parts by weight of the 4-methyl-1-pentene polymer [component (A)] from the viewpoint of heat resistance.

In the resin composition according to the present invention, in addition to the above-mentioned essential components (A) and (B), an ethylene-α-olefin copolymer having a density of 0.90 g / cm ³ or less ( C) can be contained. The ethylene
By using the α-olefin copolymer, the low-temperature embrittlement of the 4-methyl-1-pentene polymer as the component (A) can be improved, and the tear prevention of the film is further improved. be able to. In addition, by using the ethylene-α-olefin copolymer, good adhesion between the films or between the film and the food container can be further exhibited.

The ethylene-α-olefin copolymer is a copolymer of ethylene and an α-olefin other than ethylene. When the density of the ethylene-α-olefin copolymer is 0.90 g / cm ³ or less, the effect of improving the tearing of the 4-methyl-1-pentene-based polymer as the component (A) and the film-to-film or film-to-film ratio This is preferable because the adhesiveness between the container and the container can be further expected. On the other hand, when the density exceeds 0.90 g / cm ³ , the 4-methyl-1-
Although there is no problem with respect to the tearing of the pentene polymer, the adhesiveness between the films or between the film and the container may be reduced, which is not preferable. The density of the ethylene-α-olefin copolymer is more preferably 0.90 to
0.86 g / cm ³ , even more preferably 0.8
8 to 0.86 g / cm ³ . Here, the density is
It is usually measured in the same manner as the density measurement of a known polymer.

The ethylene-α-olefin copolymer is preferably an ethylene-α-olefin copolymer obtained by copolymerization using a cyclopentanedienyl complex as a catalyst.

In the above ethylene-α-olefin copolymer, the α-olefin to be copolymerized with ethylene is an α-olefin having 3 to 30 carbon atoms, for example, propylene, 1-butene, 1- Examples include pentene, 1-hexene, 1-octene, 1-heptene, 4-methylpentene-1, 4-methylhexene-1, 4,4-dimethylpentene-1, and octadecene. Among these, 1-hexene, 1-octene, 1-heptene, 4
-Methyl-pentene-1 is preferably used.

In the ethylene-α-olefin copolymer, the cyclopentadienyl complex used as a catalyst when copolymerizing ethylene and α-olefin is a compound represented by the following formula (I): And the like.

ML _X (I) wherein M is a transition metal selected from the group consisting of Zr, Ti, Hf, V, Nb, Ta and Cr, and L is
A ligand coordinated to the transition metal, a group having a cyclopentadienyl skeleton, a hydrocarbon group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, and an aryl group having 1 to 12 carbon atoms.
Roxy group, trialkylsilyl group having 1 to 12 carbon atoms, S
An O ₃ R group (R is a hydrocarbon group having 1 to 8 carbon atoms which may have a substituent such as halogen), a halogen atom or a hydrogen atom, and x is the same number as the valence of the above transition metal It is. However, when a plurality of Ls are coordinated, they may be different groups, but at least one is a group having a cyclopentadienyl skeleton. That is,
When x is 1, the L is a group having a cyclopentadienyl skeleton, and when x is 2 or more, at least one of the plurality of Ls has a cyclopentadienyl skeleton. Is a group having ]

Examples of the group having a cyclopentadienyl skeleton include, for example, cyclopentadienyl group, methylcyclopentadienyl group, dimethylcyclopentadienyl group, trimethylcyclopentadienyl group, and tetramethylcyclopentadienyl group. Enyl group, pentamethylcyclopentadienyl group, ethylcyclopentadienyl group, methylethylcyclopentadienyl group, propylcyclopentadienyl group, methylpropylcyclopentadienyl group,
Alkyl-substituted cyclopentadienyl groups such as butylcyclopentadienyl group, methylbutylcyclopentadienyl group and hexylcyclopentadienyl group; or indenyl group, 4,5,6,7-tetrahydroindenyl group, fluorenyl And the like. Further, these groups may be substituted with a halogen atom, a trialkylsilyl group or the like.

As the above-mentioned group having a cyclopentadienyl skeleton, an alkyl-substituted cyclopentadienyl group is particularly preferable among those exemplified above.

When the compound represented by the general formula (I) contains two or more groups having a cyclopentadienyl skeleton, two of the groups having a cyclopentadienyl skeleton are It may be bonded via an alkylene group such as ethylene or propylene; a substituted alkylene group such as isopropylidene or diphenylmethylene; or a substituted silylene group such as a silylene group or a dimethylsilylene group, a diphenylsilylene group or a methylphenylsilylene group.

The hydrocarbon group having 1 to 12 carbon atoms includes an alkyl group, a cycloalkyl group, an aryl group, an aralkyl group and the like. More specifically, the alkyl group includes a methyl group, Ethyl group, propyl group,
Examples of an isopropyl group and a butyl group include a cycloalkyl group such as a cyclopentyl group and a cyclohexyl group; examples of an aryl group include a phenyl group and a tolyl group; and examples of an aralkyl group include a benzyl group and a neophyl group. And the like. Examples of the alkoxy group include a methoxy group, an ethoxy group, and a butoxy group. Examples of the aryloxy group include a phenoxy group. Examples of the halogen atom include fluorine, chlorine, bromine, and iodine.

Examples of the SO ₃ R group include a p-toluenesulfonato group, a methanesulfonato group and a trifluoromethanesulfonato group.

The compound containing such a group having a cyclopentadienyl skeleton, for example, when the valence of the transition metal is 4, is more specifically represented by the following formula (II).

R ² _k R ³ _l R ⁴ _m R ⁵ _n M (II) wherein M is the above-mentioned transition metal, and R ² is a group having a cyclopentadienyl skeleton (ligand ) And R ³ , R
⁴ and R ⁵ are a group having a cyclopentadienyl skeleton, an alkyl group, a cycloalkyl group, an aryl group, an aralkyl group, an alkoxy group, an aryloxy group, a trialkylsilyl group, an SO ₃ R group, a halogen atom or a hydrogen atom, respectively. And k is an integer of 1 or more, and k + 1 + m
+ N = 4. ]

In the present invention, in the above formula (II), R
Compounds in which at least two of R ² , R ³ , R ⁴ and R ⁵ , for example, R ² and R ³ are groups (ligands) having a cyclopentadienyl skeleton are preferably used. Groups having a skeleton (eg, R ² and R ³ ) may be linked as described above.

The following are specific examples of the above compounds wherein M is zirconium. Bis (indenyl) zirconium dichloride, bis (indenyl) zirconium dibromide, bis (indenyl) zirconium bis (p-toluenesulfonato) bis 4,5,6,7-
(Tetrahydroindenyl) zirconium dichloride, bis (fluorenyl) zirconium dichloride, ethylenebis (indenyl) zirconium dichloride, ethylenebis (indenyl) zirconium dibromide, ethylenebis (indenyl) dimethylzirconium, ethylenebis (indenyl) diphenylzirconium, ethylenebis ( (Indenyl) methylzirconium monochloride, ethylenebis (indenyl) zirconiumbis (methanesulfonato), ethylenebis (indenyl) zirconiumbis (p-toluenesulfonate), ethylenebis (indenyl) zirconiumbis (trifluoromethanesulfonate), ethylene Bis (4,5,6,7-tetrahydroindenyl) zirconium dichloride, isopropylidene (cyclopentane Enyl - fluorenyl) zirconium dichloride, isopropylidene (cyclopentadienyl - methylcyclopentadienyl) zirconium dichloride, dimethylsilylene bis (cyclopentadienyl)
Zirconium dichloride, dimethylsilylenebis (methylcyclopentadienyl) zirconium dichloride, dimethylsilylenebis (dimethylcyclopentadienyl)
Zirconium dichloride, dimethylsilylenebis (trimethylcyclopentadienyl) zirconium dichloride, dimethylsilylenebis (indenyl) zirconium dichloride, dimethylsilylenebis (indenyl) zirconiumbis (trifluoromethanesulfonato), dimethylsilylenebis (4,5,6,6) 7-tetrahydroindenyl) zirconium dichloride, dimethylsilylenebis (cyclopentadienyl-fluorenyl) zirconium dichloride, diphenylsilylenebis (indenyl)
Zirconium dichloride, methylphenylsilylenebis (indenyl) zirconium dichloride, bis (cyclopentadienyl) zirconium dichloride, bis (cyclopentadienyl) zirconium dibromide, bis (cyclopentadienyl) methylzirconium monochloride, bis (cyclopentane Dienyl) ethyl zirconium monochloride, bis (cyclopentadienyl) cyclohexyl zirconium monochloride, bis (cyclopentadienyl) phenyl zirconium monochloride, bis (cyclopentadienyl) benzyl zirconium monochloride, bis (cyclopentadienyl) ) Zirconium monochloride monohydride, bis (cyclopentadienyl) methylzirconium monohydride, bis (cyclopentadienyl) Methyl zirconium, bis (cyclopentadienyl) diphenyl zirconium, bis (cyclopentadienyl) dibenzyl zirconium, bis (cyclopentadienyl) zirconium methoxychloride, bis (cyclopentadienyl) zirconium ethoxycyclolide, bis (cyclopentane Dienyl) zirconium bis (methanesulfonato), bis (cyclopentadienyl) zirconium bis (p-toluenesulfonato), bis (cyclopentadienyl) zirconium bis (trifluoromethanesulfonato), bis (methylcyclopentadiene) Enyl) zirconium dichloride, bis (dimethylcyclopentadienyl) zirconium dichloride, bis (dimethylcyclopentadienyl) zirconium ethoxycyclolide, bis (dimethylcyclopen Dienyl) zirconium bis (trifluoromethanesulfonato), bis (ethylcyclopentadienyl) zirconium dichloride, bis (methylethylcyclopentadienyl) zirconium dichloride, bis (propylcyclopentadienyl) zirconium dichloride, bis (methylpropylcyclo) (Pentadienyl) zirconium dichloride, bis (butylcyclopentadienyl) zirconium dichloride, bis (methylbutylcyclopentadienyl) zirconium dichloride, bis (methylbutylcyclopentadienyl) zirconium bis (methanesulfonato), bis (trimethyl) Cyclopentadienyl) zirconium dichloride, bis (tetramethylcyclopentadienyl) zirconium dichloride, bis (pentamethylcyclopentadi Enyl) zirconium dichloride, bis (hexylcyclopentadienyl) zirconium dichloride, bis (trimethylsilylcyclopentadienyl)
Zirconium dichloride.

In the compounds exemplified above, disubstituted cyclopentadienyl rings such as dimethylcyclopentadienyl include 1,2- and 1,3-substituted compounds.
Trisubstituted compounds such as dimethylcyclopentadienyl are 1,2,2
Includes 3- and 1,2,4-substitutes. Also propyl,
Alkyl groups such as butyl are n-, i-, sec-, te
It includes isomers such as rt-. Examples of the compound also include a cyclopentadienyl complex in which zirconium is replaced with titanium, hafnium, vanadium, niobium, tantalum, or chromium in the above-mentioned compound in which M is zirconium.

The cyclopentadienyl complex is
When used, they can be used alone or as a mixture. It may be used after being diluted with a hydrocarbon or a halogenated hydrocarbon. In particular, in the present invention, as the cyclopentadienyl complex, a zirconocene compound in which the central metal atom is zirconium and whose ligand is a group having at least two cyclopentadienyl skeletons is preferably used.

The above cyclopentadienyl complex is
It can be used in combination with an ordinary aluminoxane compound or a compound which reacts with the cyclopentadienyl complex to form a stable anion.

The cyclopentadienyl complex catalyst of the present invention is disclosed in JP-A-4-253711.
JP-A-4-279592, JP-T-6-50358
No. 5, JP-A-3-188092 or JP-A No.
A polymerization catalyst described in JP-A-84407 can also be used.

The mixing ratio of ethylene to α-olefin in the ethylene-α-olefin copolymer is preferably 40 to 98% by weight of ethylene and preferably 60 to 2% by weight of α-olefin.

The ethylene-α-olefin copolymer is prepared by converting ethylene and α-olefin in the presence of a cyclopentadienyl complex to 100-3,000 kg / c.
m ² , preferably 300 to 2,000 kg / cm ² ,
It can be produced by polymerizing at a temperature of 25 to 250 ° C, preferably 150 to 200 ° C by a high pressure ionic polymerization method. In particular, when the above-mentioned cyclopentadienyl complex and the above-mentioned aluminoxane compound are used in combination, polymerization is disclosed in
JP-A-1-130314, JP-A-60-35006,
According to the methods described in JP-A-58-19309, JP-A-60-35008, JP-A-3-1630088, etc., and the above cyclopentadienyl complex and a stable anion reacted with the cyclopentadienyl complex Can be used in combination with the compounds which form the carboxylic acids described in EP 277,004, WO 92/0172.
Polymerization can be carried out according to the high-pressure ionic polymerization method described in JP-A No. 3 (KOKAI) No. 3 and the like.

The molecular weight distribution of the ethylene-α-olefin copolymer is preferably such that the ratio Mw / Mn of the weight average molecular weight to the number average molecular weight measured by GPC is 4 or less, preferably 2 or less. Is more preferred. Further, the melt index of the ethylene-α-olefin copolymer (M
I) (ASTM D1238) is preferably 0.01
~ 300g / 10min, more preferably 0.1 ~ 15
0 g / 10 min, particularly preferably 0.5 to 30 g / 1
0 min.

Further, as the above-mentioned ethylene-α-olefin copolymer, those obtained by copolymerization by a usual method using a known metallocene catalyst can also be used.

The content of the ethylene-α-olefin copolymer is preferably 1 to 100 parts by weight based on 100 parts by weight of the 4-methyl-1-pentene polymer (component (A)).
70 parts by weight. When the content of the ethylene-α-olefin copolymer is less than 1 part by weight, 4-methyl-1-
The effect of modifying the pentene polymer [component (A)] is small,
Tear may occur, and the adhesion between the films or between the film and the container may decrease. On the other hand, when the amount exceeds 70 parts by weight, the resin of the component (A) in a matrix state may contain (C)
The heat resistance effect may not be obtained due to, for example, inversion of the component resin without being dispersed.

In particular, the content of the above-mentioned ethylene-α-olefin copolymer is selected from the viewpoints of further improving flexibility at low temperatures, preventing irregular tearing, and further improving the adhesion between films or between a film and a container. 4-methyl-1-pentene polymer [component (A)]
More preferably, it is 30 parts by weight.

Further, the resin composition according to the present invention includes:
High pressure method polyethylene (D) can be contained.
By using the high-pressure polyethylene, the melt properties of the entire resin composition can be easily controlled because of the high melt tension characteristics of the high-pressure polyethylene.

The high-pressure polyethylene is a polyethylene produced by a so-called high-pressure method. For example, low-density polyethylene (hereinafter, also referred to as "LDPE") produced by a high-pressure radical polymerization method can be used.

The content of the above-mentioned high-pressure polyethylene is determined based on the above-mentioned 4-methyl-1-pentene polymer [component (A)] 10.
It is preferably 1 to 30 parts by weight with respect to 0 parts by weight.
If the content of the high-pressure polyethylene is less than 1 part by weight, the effect of increasing the melt tension of the resin composition may be reduced, and if it exceeds 30 parts by weight, the melting energy for the resin composition is reduced. Therefore, heat resistance may be reduced. In particular, the content of the high-pressure polyethylene is more preferably 10 to 30 parts by weight based on 100 parts by weight of the 4-methyl-1-pentene polymer [component (A)].

Further, the resin composition according to the present invention includes:
Polybutene (E) can be contained. By using the polybutene, it is possible to further impart tackiness to the obtained film.

The above polybutene has a number average molecular weight of 3 because it is easier to develop the tackiness imparted to the film.
It is preferably from 00 to 3000. The number average molecular weight of the polybutene is more preferably from 500 to 2,000, most preferably from 1,000 to 1,500.

The content of the polybutene is preferably 1 to 15 parts by weight based on 100 parts by weight of the 4-methyl-1-pentene polymer (component (A)). When the content of the polybutene is less than 1 part by weight, the adhesive strength that can be given to the film is reduced, and the adhesive strength between the films or between the film and the container may be reduced.
If the amount exceeds the weight part, the workability at the time of film forming becomes difficult, or after winding the obtained film, it becomes difficult to unwind again, or the film is slightly adhered,
It may be difficult to use it by sticking together with wrinkles.
In particular, the content of the polybutene is 4-methyl-1
More preferably, the amount is 1 to 10 parts by weight based on 100 parts by weight of the pentene polymer [component (A)].

Further, the resin composition according to the present invention includes:
In addition to the above-described components, if necessary, ordinary additives such as antioxidants, colorants, ultraviolet absorbers, inorganic fillers, heat stabilizers, antistatic agents, antifoggants, tackifiers, etc. It can be appropriately contained. The additive is contained in a generally known amount within a range that does not impair the effects of the present invention.

The resin composition according to the present invention comprises the above-mentioned components (A) and (B), and if necessary, (C)
The components (D) and (E) and other additives are added, and the mixture is kneaded sufficiently by a conventional method, for example, dry blending, dry blending, followed by sufficient kneading with a Banbury mixer or an extruder, or kneading, followed by pelletization with a pelletizer or the like. It can be manufactured by a method.

As a method of forming the wrap film of the present invention from the above resin composition, for example, a known inflation method and a T-die method (methods using a film forming apparatus such as an ordinary inflation apparatus and a T-die apparatus, respectively) Etc. can be adopted. In the forming apparatus, the resin composition is heated at a temperature of preferably 270 to 320 ° C., and then extruded and cooled to form a film. In the case of the above-mentioned inflation method, any cooling method of an air cooling type or a water cooling type may be used. In addition, in order to improve the transparency of the obtained wrap film, it is preferable to perform quenching after extrusion. Alternatively, the above resin composition according to the present invention may be used on the surface side to form a multilayer film by coextrusion.

The wrap film of the present invention may be a non-stretched film, but is preferably a stretched film, particularly a biaxially stretched film. By biaxially stretching, the cutting property by the saw blade is improved. In this case, the stretching method is not particularly limited, and the stretching is carried out by a generally known method.
It is preferably in the range of 2 times or more, particularly 2 to 10 times.

The wrap film of the present invention has a thickness of 10 to 20 μm so that it can easily fit into the shape of a container.
m, particularly preferably in the range of 10 to 15 μm.

The wrap film of the present invention obtained as described above has good safety, flexibility, tackiness, cutability, transparency and tear resistance, especially low-temperature flexibility, and can be used as a film or film. It has good adhesiveness to containers and is suitable for heating, refrigeration, and frozen storage by a microwave oven.

Accordingly, the wrap film of the present invention can be suitably used as a household or business wrap film used for heating foods in a microwave oven or for refrigeration or frozen preservation of foods.

[0055]

The present invention will be described in more detail with reference to the following Examples and Comparative Examples, but the present invention is not limited to these Examples.

Examples 1 to 5 and Comparative Examples The respective components shown in Table 1 below were kneaded to prepare a resin composition. Next, the resin composition was heated to 320 ° C. using a normal film forming apparatus, and then extruded and cooled to form a film. This was biaxially stretched (stretching ratio: 3.0 times in the longitudinal direction and 3.0 times in the transverse direction) by a usual stretching method to form a wrap film having a thickness of 12 μm.

The obtained wrap film was evaluated for tackiness, cuttability, flexibility, heat resistance and low-temperature flexibility according to the following evaluation criteria. The results are shown in Table 3 below. For details of the components used in each example,
The results are shown in Table 2 below.

Evaluation Criteria [Adhesiveness] A sensory test was conducted when the wrap film was actually adhered to setware, and evaluated according to the following criteria. A: Excellent. ；: Good. Δ: No problem in practical use. X: poor.

[Cutability] The straightness of the tear when the wrap film was cut with a saw blade used for a commercially available wrap film was examined and evaluated according to the following criteria. ○; Δ: Going straight, but sometimes caught on the way. X: It did not go straight and was defective.

[Flexibility] The above wrap film is 10 cm
The evaluation film cut into a size of × 10 cm
Under a condition of 0 ° C., a sensory test was carried out when rolled by hand and evaluated according to the following criteria. A: Excellent. ；: Good. Δ: No problem in practical use. X: poor.

[Heat resistance] The dish on which the tempura was placed was wrapped with the above wrap film, and the heat resistance of the wrap film when heated and cooked in a microwave oven was evaluated according to the following criteria. ；: There was no problem. Δ: Small hole level. X: The level at which a large hole was formed.

[Low temperature flexibility]
The evaluation film cut into a size of cm × 10 cm was subjected to a sensory test when rolled by hand under a condition of −10 ° C., and evaluated according to the following criteria. A: Excellent. ；: Good. Δ: No problem in practical use. X: poor.

[0063]

[Table 1]

[0064]

[Table 2]

[0065]

[Table 3]

From the results in Table 3 above, it was found that 4-methyl-1
-The wrap film of the present invention formed from a resin composition containing 1 to 15 parts by weight of an oil or fat [Component (B)] based on 100 parts by weight of a pentene polymer [Component (A)] It can be seen that Examples 1 to 5) are excellent in adhesiveness, cutability, flexibility and low-temperature flexibility, particularly excellent in low-temperature flexibility and adhesiveness, compared to the wrap film of the comparative example. .

[0067]

The wrap film of the present invention has good safety, flexibility, tackiness, cutability, transparency and tear resistance, especially low-temperature flexibility and adhesion between films or between a film and a container. It is suitable for heating, refrigeration, and freezing by microwave oven.

Claims (7)

[Claims] 1. A resin composition comprising 1 to 15 parts by weight of a fat or oil (B) based on 100 parts by weight of a 4-methyl-1-pentene polymer (A). Wrap film. 2. The wrap film according to claim 1, wherein the fat (B) is a hydrocarbon compound. 3. The wrap film according to claim 1, wherein said fat (B) is an ester compound of glycerin. 4. The wrap film according to claim 1, wherein the fat (B) is sucrose polyester. 5. The method according to claim 1, wherein the resin composition is 4-methyl-1
The ethylene-α-olefin copolymer (C) having a density of 0.90 g / cm ³ or less is contained in an amount of 1 to 70 parts by weight based on 100 parts by weight of the pentene-based polymer (A).
A wrap film according to any one of claims 1 to 4. 6. The method according to claim 1, wherein the resin composition is 4-methyl-1
The wrap film according to any one of claims 1 to 5, comprising 1 to 30 parts by weight of a high-pressure process polyethylene (D) based on 100 parts by weight of the pentene polymer (A). 7. The method according to claim 7, wherein the resin composition is 4-methyl-1
-The polypentene (E) is contained in an amount of 1 to 15 parts by weight based on 100 parts by weight of the pentene polymer (A).
7. The wrap film according to any one of 6.