JPH11240984A - Oriented film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an oriented film that has excellent elastic recovery, strength and handling properties and shows markedly high air permeability. SOLUTION: This air-permeating film is formed by melt-extruding a resin composition containing the following component A and component B and oriented mono- or biaxially: the component A: an ethylene->=3C α-olefin copolymer having the following (a)-(c) properties: (a) MFR is 0.010-20 g/10 minutes; (b) Density is <=0.935 g/cm<3> ; (c) The elution (Y: in wt.% based on the whole weight of the component A) in the temperature rise elution fractionation (TREF) at 50 deg.C satisfies the following conditions: (1) when the density (D) of the component A is <=0.91 g/cm<3> , Y<=-455D+4105 (where Y<=100) (2) when the density (D) of the component A is >=0.91 g/cm<3> , Y <= 10 The component B: a particulate inorganic filler with an average particle size of <=10 μm and a bulk density of 0.1-0.7 g/cm<3> .

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a thin-walled air-permeable molded article having excellent elastic recovery, strength and texture for use in sanitary materials, and having excellent air permeability. The present invention relates to an air-permeable stretched film having excellent weatherability and no smoke or roll contamination during processing, as well as excellent air permeability and strength.

[0002]

2. Description of the Related Art It is already known that a film or the like made of a composition of an olefin resin and an inorganic filler is stretched in a uniaxial or biaxial direction to produce a breathable film having open (penetrated) voids. Films using this composition are used for sanitary materials such as disposable disposable diapers; for the protection of timber construction from water; It is used for outdoor ventilation sheets, such as protective sheets to be spread for protection. However, conventionally proposed resin compositions are inferior in stretchability at the time of molding and have insufficient strength, so that it has been difficult to make them thinner. However, there has been a demand for thinning in order to save resources and rationalize products, but the conventional resin composition could not sufficiently respond to such required performance. The performance required for such disposable disposable diapers and the like includes, in addition to the above-mentioned thinning, air permeability, texture, and the like. It has become. That is, since the disposable diaper absorbs moisture, products with poor air permeability are likely to cause stuffiness, and are not preferred by consumers. At the same time, consumers are now demanding higher-end products than conventional products, and disposable diapers are also desired to be in close contact with the body, such as underpants. A material that shrinks (elastic recovery) has been required. Further, needless to say, a feeling that is better than the conventional one has been desired. Furthermore, the conventional air-permeable sheets and films for outdoor use have poor air-permeability, lack strength, and are difficult to be thin.
In addition, due to insufficient weather resistance, when used in the summer, it deteriorates in one or two months and becomes tattered. For this reason, a method of adding a weather resistance imparting agent (ultraviolet ray inhibitor, light stabilizer) is used, but this method produces smoke during molding,
Even after the chill roll is stained with a bleed object, and even after it becomes a product, the printability is poor and the ink is easy to peel off, and dirt such as dust easily adheres, and there are many problems, such as a breathable film for outdoor use It was not enough for practical use.

[0003]

SUMMARY OF THE INVENTION An object of the present invention is to provide a breathable stretched film which has excellent elastic recovery, strength and texture and is extremely excellent.

[0004]

Means for Solving the Problems [Summary of the Invention] The present inventors have made intensive studies to solve the above-mentioned problems, and as a result, have found that an ethylene / α-olefin copolymer having specific properties It has been found that the use of a resin composition obtained by blending the above inorganic fillers can achieve the object of the present invention, thereby completing the present invention. That is, the breathable stretched film of the present invention comprises the following components A and B, and the mixing ratio thereof is 20 to 80% by weight based on the total amount of both components A and B, and component B Is 80 to 20% by weight, and is formed by melt-extrusion and uniaxially or biaxially stretching. Component A: a copolymer of ethylene having the following properties (a) to (c) and an α-olefin having 3 or more carbon atoms: (a) MFR of 0.01 to 20 g / 10 min (b) Density 0.935 g / cm ³ or less (c) The amount of elution at 50 ° C. (Y: wt% based on the total amount of component A) by temperature rise elution fractionation (TREF) satisfies the following condition: The density (D) of component A is When less than 0.91 g / cm ³ , Y ≦ −4500D + 4105 (where Y ≦ 100) When the density (D) of the component A is 0.91 g / cm ³ or more, Y ≦ 10 Component B: average particle diameter Is 10 μm or less, and the bulk density is 0.1 to
Particulate inorganic filler 0.7 g / cm ³

[I] Constituent Component (1) Component (1) Component A (α-olefin copolymer having 3 or more carbon atoms of ethylene) (a) Properties Constituent of the filler-containing resin composition of the present invention. As the α-olefin copolymer having 3 or more ethylene and carbon atoms of the component A, it is important to use those having the following physical properties, preferably those having the following physical properties.

MFR The α-olefin copolymer having 3 or more ethylene and carbon atoms used in the present invention has an MFR according to JIS-K7210.
(Melt Flow rate: Melt flow rate) 0.01 to 20 g / 10 min, preferably 0.1 to 10 g
/ 10 minutes, particularly preferably 0.5 to 5 g / 10 minutes. If the MFR is larger than the above range, the molding becomes unstable. On the other hand, if the MFR is smaller than the above range, the resin pressure becomes too large, and the production of the product is reduced, which is not practical.

Density The α-olefin copolymer having 3 or more ethylene and carbon atoms used in the present invention has a density according to JIS-K7112 of 0.935 g / cm ³ or less, and preferably 0.86 to 0.15 g / cm ³ .
930 g / cm ³ , particularly preferably 0.88 to 0.92
5 g / cm ³ , especially 0.88 or more and 0.910 g / c
shows a less than m ^3. When the density is higher than the above range, the tensile strength and the feeling of the stretched film become insufficient. Also, if the density is smaller than the above range,
Blocking occurs due to stickiness of the film surface, and the film cannot be put to practical use.

Amount of elution at 50 ° C. by temperature rise elution fractionation (TREF) The amount of elution at 50 ° C. by temperature rise elution fractionation (TREF) of the α-olefin copolymer having 3 or more ethylene and carbon used in the present invention ( Y:% by weight based on the total amount of component A) preferably satisfies the following conditions. 1) When the density (D) of the component A is less than 0.91 g / cm ³ , Y ≦ −4500D + 4105 (where Y ≦ 1
00), preferably Y ≦ −4650D + 4238 (where Y ≦ 100). 2) When the density (D) of the component A is 0.91 g / cm ³ or more, Y ≦ 10, preferably Y ≦ 7. Measurement of elution curve by temperature rise elution fractionation Temperature rise elution fractionation
ionation: TREF) is described in “Jouranl of App
lied Polymer Science, Vol. 26, 4217-4231, (1981) "and" Polymer Symposium Proceedings 2P1C09 (1985) ". T
The principle of REF measurement is as follows. First, a polymer to be measured is completely dissolved in a solvent. Thereafter, cooling is performed to form a thin polymer layer on the surface of the inert carrier. Such a polymer layer is formed by forming an easily crystallizable material on the inner side (the side closer to the surface of the inert carrier) and a hardly crystallizable material on the outer side. Next, when the temperature is increased continuously or stepwise,
In the low temperature stage, the polymer is eluted from the amorphous portion in the target polymer composition, that is, the polymer having a high degree of short-chain branching. The linear part without the elution is eluted and the measurement is completed. By detecting the concentration of the eluted component at each temperature, the composition distribution of the polymer can be seen from a graph drawn by the amount and temperature of the elution.

The peak temperature of the elution curve obtained by temperature-rise elution fractionation The α-olefin copolymer having 3 or more ethylene and carbon atoms used in the present invention is obtained by temperature-rise elution fractionation (TREF: Te).
One or more peaks of the elution curve obtained by mperature rising elution fractionation exist, and the peak temperature is 30 to 100 ° C, preferably 35 to 85 ° C, particularly preferably 40 to 75 ° C. In addition, “one peak” refers to a line that descends from the apex as the origin in the TREF differential elution curve, and the rising angle when re-rising does not exceed 90 degrees within the range of the elution temperature of 3 ° C. A thing. When the peak temperature of the elution curve exceeds the above-mentioned temperature, the elastic recovery becomes poor, so that it is not practical. Also,
If the peak temperature of the elution curve is lower than the above temperature, the air permeability becomes insufficient, which is not preferable. Further, when the height of this peak is H and the width of half the height of the peak is W, the value of H / W is 1 or more, preferably 1 to 20, particularly preferably 1 to 15, More preferably, they exhibit physical properties of 1 to 10, most preferably 1 to 5. When the above H / W is less than the above value, the stickiness component increases and the sealing property becomes poor over time, so that it is not practical.

Q value [0010] The α-olefin copolymer having 3 or more ethylene and carbon atoms is obtained by size exclusion chromatography (Size Exclusion C).
Q value (weight average molecular weight / number average molecular weight) determined by hromatography (SEC) is 4 or less, preferably 3
Hereinafter, particularly preferably those exhibiting physical properties of 2.5 or less,
High tensile strength is also preferable.

When the composition of the present invention is used as a material for a sheet or the like for outdoor use, the α-olefin copolymer having ethylene / carbon number of 4 or more has a boiling n-hexane extraction amount. Is 20% by weight
Or less, preferably 15% by weight or less, particularly preferably 10% by weight.
% By weight or less. If the boiling n-hexane extraction amount exceeds the above range, the air permeability of the stretched film is undesirably reduced.

(B) Production of α-olefin copolymer having 3 ethylene or more carbon atoms The production method of α-olefin copolymer having 3 ethylene atoms or more carbon atoms used in the present invention is described in JP-A-58-19309. Same 5
Nos. 9-95292, 60-35005, 60-3
No. 5006, No. 60-35007, No. 60-3500
No. 8, No. 60-35009, No. 61-130314
, Japanese Patent Application Laid-Open No. H3-163088, European Patent Application Publication No. 420436, U.S. Pat.
No. 5438 and International Publication WO 91/0425.
7, a metallocene catalyst, particularly a metallocene-alumoxane catalyst, or a metallocene compound as disclosed in, for example, International Publication WO92 / 01723 and a metallocene compound described below. This is a method in which ethylene as a main component and α-olefin as a subcomponent are copolymerized using a catalyst composed of a compound which becomes a stable anion by reacting with the compound.

The above-mentioned compound which reacts with a metallocene compound to form a stable anion is an ionic compound or an electrophilic compound formed from an ion pair of a cation and an anion, and is a compound which reacts with a metallocene compound to form a stable anion. To form polymerization active species.

Among them, the ionic compound is represented by the following general formula (I)
I). General formula (II): [Q] ^{m +} [Y] ^m− (m is an integer of 1 or more) Q is a cation component of an ionic compound, and is a carbonium cation, a tropylium cation, an ammonium cation, an oxonium cation, a sulfonium Cation,
Examples thereof include phosphonium cations and the like, and further include metal cations and organic metal cations which are easily reduced by themselves. These cations are described in JP-T-Hei 1-5.
Not only a cation capable of providing a proton as disclosed in Japanese Patent No. 01950 or the like, but also a cation that does not provide a proton may be used. Specific examples of these cations include triphenylcarbonium, diphenylcarbonium, cycloheptatrienium, indenium, triethylammonium, tripropylammonium, tributylammonium, N, N-dimethylanilinium, dipropylammonium, dicyclohexylammonium, Triphenylphosphonium, trimethylphosphonium, tri (dimethylphenyl) phosphonium,
Tri (methylphenyl) phosphonium, triphenylsulfonium, triphenyloxonium, triethyloxonium, pyrylium, silver ion, gold ion,
Platinum ion, palladium ion, mercury ion, ferrocenium ion and the like can be mentioned.

Y is an anionic component of an ionic compound, which is a component which reacts with a metallocene compound to form a stable anion, such as an organic boron compound anion, an organic aluminum compound anion, an organic gallium compound anion, and an organic phosphorus compound. Anions, organic arsenic compound anions, organic antimony compound anions, and the like, specifically, tetraphenylboron, tetrakis (3,4,
5-trifluorophenyl) boron, tetrakis (3,
5-di (trifluoromethyl) phenyl) boron, tetrakis (3,5- (t-butyl) phenyl) boron, tetrakis (pentafluorophenyl) boron, tetraphenylaluminum, tetrakis (3,4,5-trifluorophenyl) ) Aluminum, tetrakis (3,5-
Di (trifluoromethyl) phenyl) aluminum, tetrakis (3,5-di (t-butyl) phenyl) aluminum, tetrakis (pentafluorophenyl) aluminum, tetraphenylgallium, tetrakis (3
4,5-trifluorophenyl) gallium, tetrakis (3,5-di (trifluoromethyl) phenyl) gallium, tetrakis (3,5-di (t-butyl) phenyl)
Gallium, tetrakis (pentafluorophenyl) gallium, tetraphenylphosphorus, tetrakis (pentafluorophenyl) phosphorus, tetraphenylarsenic, tetrakis (pentafluorophenyl) arsenic, tetraphenylantimony, tetrakis (pentafluorophenyl) antimony, decaborate, undeca Borate, carbado degaborate, decachloro decaborate and the like.

The electrophilic compound is a compound known as a Lewis acid compound, which reacts with a metallocene compound to form a stable anion to form a polymerization active species. Examples include metal oxides known as solid acids. Specific examples include magnesium halide and Lewis acidic inorganic oxide.

Α-olefin Here, the α-olefin is an α-olefin having 3 or more carbon atoms, for example, propylene, 1-butene, 1-pentene, 1-hexene, 1-octene, 1-heptene,
-Methylpentene-1,4-methylhexene-1,4,
4-dimethylpentene-1, octadecene and the like. Among these α-olefins, preferably those having 4 to 4 carbon atoms
12, particularly preferably 6 to 10, one or more α
2-60% by weight of olefin, preferably 5-50% by weight, and 40-98% by weight of ethylene, preferably 50-9%.
It is preferred to copolymerize with 5% by weight.

[0018] The polymerization method for copolymerizing the ethylene · alpha-olefin copolymer, a gas phase method, slurry method, a solution method and a high pressure ion polymerization method. Among these, a solution method and a high-pressure ionic polymerization method are preferred, and production by a high-pressure ionic polymerization method is particularly preferred. The high pressure ionic polymerization method is described in JP-A-56-18607 and JP-A-58-2251.
No. 06, the pressure is 200 kg /
cm ² or more, preferably 300 to 2,000 kg / cm
^{2. The} temperature is 125 ° C or higher, preferably 130 to 250
This is a method for continuously producing an ethylene polymer, which is carried out under a reaction condition of 150 ° C., particularly 150 to 200 ° C.

(2) Component B (Particulate Inorganic Filler) As the component B of the filler-containing resin composition of the present invention, a particulate inorganic filler having the following physical properties (a) and (b) may be used. is important. (A) Average particle size The average particle size of the granular inorganic filler of the component B used in the present invention is 10 µm or less, preferably 0.1 to 5 µm or less.
Particularly preferably, the thickness is 0.5 to 2 μm or less. In order to determine the average particle size, the specific surface area is measured by an air permeation method, and calculated by the following equation. dm = 60,000 / (ρ · Sw) [where dm represents the average particle size (μm), ρ represents the true specific gravity of the filler (g / cm ³ ), and Sw represents the specific surface area of the filler (cm ^2). / G)] As a specific surface area measuring device, for example, a Shimadzu powder specific surface area measuring device SS-100 type can be used, and Kozeny-Carman
The specific surface area can be determined by applying the equation. If the average particle size of the particulate inorganic filler is too large, the appearance of the stretched film is hindered. In the case of producing a thin stretched film having a thickness of 100 μm or less, holes, stretching unevenness, and the like are generated, so that stable stretching is performed. Sex is impaired.

(B) Bulk Density The bulk density of the granular inorganic filler of the component B used in the present invention (measured according to JIS K5101) is from 0.1 to
0.7 g / cm ³ , preferably 0.2 to 0.6 g / cm ^3
3 , particularly preferably 0.3 to 0.5 g / cm ³ . If the bulk density of the above-mentioned granular inorganic filler is too small, the air permeability of the stretched film will be reduced, and if it is too large, the strength of the film will be reduced, causing a problem in practicality.

(C) Water Content The particulate inorganic filler of Component B used in the present invention preferably has a water content of 3,000 ppm or less, preferably 1,000 ppm or less. If the water content of the particulate inorganic filler is more than the above range, foaming phenomenon is likely to occur at the time of molding, making it difficult to perform stable film molding, or causing poor appearance such as poor hue or film,
The filler tends to undergo secondary aggregation, which tends to cause poor appearance and poor stretching. Such inorganic fillers include calcium carbonate, calcium oxide, zeolite, amorphous aluminosilicate, clay,
Synthetic silica, titanium oxide, alumina, barium sulfate, aluminum sulfate, magnesium hydroxide and the like, among which calcium carbonate, zeolite, amorphous aluminosilicate, barium sulfate, synthetic silica, magnesium hydroxide and the like are preferable, and particularly calcium carbonate and Barium sulfate is preferred. These can be used alone or in combination of two or more.

(3) Component C (Dispersant) The filler-containing resin composition of the present invention is basically composed of the above components A and B, and additionally comprises a dispersant for the particulate inorganic filler. 0.1 to 15 parts by weight, preferably 0.5 to 7 parts by weight, based on 100 parts by weight of both components.
Parts by weight, particularly preferably 1 to 5 parts by weight. Examples of the dispersant include a saturated or unsaturated fatty acid ester having 9 to 40 carbon atoms, triglyceride using a saturated or unsaturated fatty acid having 2 to 30 carbon atoms, and a liquid or waxy hydroxyl-terminated liquid polybutadiene hydrogenated polybutadiene. Hydroxy saturated hydrocarbons, liquid or waxy hydrocarbon polymers or mixtures of such copolymers with epoxy group-containing organic compounds, titanates, monohydric higher alcohols or derivatives thereof, higher fatty acid amides, higher amines, saturated or Use of liquid or waxy components such as alcohol derivatives selected from homopolymers, copolymers, ether compounds, amine compounds, amide compounds, and ester compounds of the alcohols derived from unsaturated dihydric or higher alcohols. Can be. These can be used alone or in combination of two or more. Among the above, a saturated or unsaturated fatty acid ester having 9 to 40 carbon atoms, a triglyceride using a saturated or unsaturated fatty acid having 2 to 30 carbon atoms, a polyhydroxy saturated liquid obtained by hydrogenating a liquid or waxy hydroxyl-terminated liquid polybutadiene. It is preferred to use hydrocarbons. Among them, a saturated or unsaturated fatty acid ester having 9 to 40 carbon atoms is particularly preferable.

[0023] Specific examples of the unsaturated fatty acid esters above unsaturated fatty acid esters, for example, (poly) ethylene glycol oleate, (poly) propylene glycol oleate, glyceryl oleate,
Sorbitan oleate, (poly) ethylene glycol sorbitan oleate, butyl oleate, pinacol oleate, m-cresol oleate, pentaerythritol oleate, glyceryl linoleate, glyceryl ricinolate, methyl ricinolate, ethyl ricinolate, butyl ricinoleate Nolate, methyl acetyl ricinolate, ethyl acetyl ricinolate, butyl acetyl ricinolate, (poly) ethylene glycol ricinolate,
Glyceryl acetyl ricinolate, glyceryl erucate and the like can be mentioned. Of these, glyceryl hydroxy unsaturated fatty acid esters are preferred, and glyceryl ricinoleate, particularly glyceryl triricinoleate, is preferred.

[0024] Specific examples of the saturated fatty acid ester wherein the saturated fatty acid esters, (poly) ethylene glycol laurate, (poly) propylene glycol laurate, glyceryl Rirura weight, sorbitan laurate, glyceryl myristate, glyceryl palmitate, Buchirusutea Rate, ethylene glycol stearate, propylene glycol stearate, pinacol stearate, m-cresol stearate,
(Poly) ethylene glycol stearate, (poly) propylene glycol stearate, glyceryl stearate, pentaerythritol stearate, sorbitan stearate, (poly) ethylene glycol sorbitan stearate, methylhydroxystearate, ethylhydroxystearate, butylhydroxy Stearate, methyl acetyl hydroxystearate, ethyl acetyl hydroxystearate, butyl acetyl hydroxystearate, ethylene glycol hydroxystearate, propylene glycol hydroxystearate, pinacol hydroxystearate, m-cresol hydroxystearate, (poly) ethylene glycol Hydroxystearate, (poly) propylene glycol hydroxys Areto, pentaerythritol hydroxystearate, sorbitan hydroxystearate, ethylene glycol sorbitan hydroxystearate, glyceryl hydroxystearate, mention may be made of glyceryl acetyl hydroxystearate like.

Among these, ethylene glycol hydroxystearate, propylene glycol hydroxystearate, pinacol hydroxystearate, m
-Cresol hydroxystearate, (poly) ethylene glycol hydroxystearate, (poly) propylene glycol hydroxystearate, pentaerythritol hydroxystearate, sorbitan hydroxystearate, ethylene glycol sorbitan hydroxystearate, glycerin hydroxystearate, glyceryl acetylhydroxy Glyceryl hydroxy saturated fatty acid esters such as stearate are preferred. More preferred is glyceryl hydroxystearate, particularly preferred is glyceryl tri-12-hydroxystearate.

When a saturated ester is used as a fatty acid ester, there is almost no fuming at the time of molding as compared with a case where an unsaturated ester is used. And the obtained stretched film is excellent in odorlessness. By adding the above components, the dispersibility of the particulate inorganic filler in the polymer is significantly improved, and thereby the stretchability of the film is improved, so that the film can be thinned and the air permeability is also improved, In addition, the feeling of softness is increased, and the texture is improved.

(4) Component D (Copolymer of Ethylene and Cyclic Aminovinyl Compound) The filler-containing resin composition of the present invention is basically composed of the above components A and B. It may contain a copolymer with a cyclic aminovinyl compound represented by the following general formula (I). When used in applications requiring weather resistance such as outdoor use, the compound D improves the weather resistance and printability of the resin composition, and does not cause smoke or roll stains during processing. A highly productive product is obtained.

[0028]

Embedded image

In the formula, R ¹ and R ² represent a hydrogen atom or a methyl group, and R ³ represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. Representative examples of the cyclic aminovinyl compound represented by the general formula (I) are as follows. 1) 4-acryloyloxy-2,2,6,6-tetramethylpiperidine 2) 4-acryloyloxy-1,2,2,6,6-pentamethylpiperidine 3) 4-acryloyloxy-1-ethyl-2 , 2,
6,6-tetramethylpiperidine 4) 4-acryloyloxy-1-propyl-2,2,
6,6-tetramethylpiperidine 5) 4-acryloyloxy-1-butyl-2,2,
6,6-tetramethylpiperidine 4-methacryloyloxy-2,2,6,6-tetramethylpiperidine 7) 4-methacryloyloxy-1,2,2,6,6-
Pentamethylperidine 8) 4-methacryloyloxy-1-ethyl-2,2,
6,6-tetramethylpiperidine 9) 4-methacryloyloxy-1-butyl-2,2,
6,6-tetramethylpiperidine 10) 4-crotonoyloxy-2,2,6,6-tetramethylpiperidine 11) 4-crotonoyloxy-1-propyl-2,
2,6,6-tetramethylpiperidine

Copolymer In the copolymer of ethylene and the cyclic aminovinyl compound, the content of the cyclic aminovinyl compound is less than 1 mol%,
Preferably it is 0.1-0.7 mol%. The MFR of the copolymer is 0.1 to 200 g / 10 min, preferably 0.5 to 100 g / 10 min, particularly preferably 0.7 to 100 g / 10 min.
50 g / 10 min. The copolymer is disclosed in, for example,
No.-80215, which can be produced by a high-pressure radical polymerization method. Specifically, ethylene and a cyclic aminovinyl compound can be produced at 1,000 to 5,000 kg /
pressure of cm ^2, to radical polymerization at a temperature of 100 to 400 ° C..

[II] Quantitative Ratio The compounding ratio of the component A and the component B is based on the total amount of the component A and the component B, and the component A: the component B = 20 to 80% by weight: 80 to 20% by weight, preferably Is component A: component B = 3
0 to 70% by weight: 70 to 30% by weight, particularly preferably Component A: Component B = 35 to 60% by weight: 65 to 40% by weight. If the blending ratio of the component B is too small, the texture of the obtained stretched film will be reduced. If the blending ratio is too large, the stretchability at the time of film formation will be reduced, and the film will lack practicality. When component C (dispersant) is blended, the total amount of component A and component B is 100 parts by weight,
0.1 to 15 parts by weight, preferably 0.5 to 7 parts by weight, particularly preferably 1 to 5 parts by weight can be added. If the compounding amount of this component is too small than the above range, when a stretched film is manufactured to be thin and at a low magnification, local necking occurs, the thickness becomes uneven, unevenness occurs, and the commercial value is significantly impaired. Will be. On the other hand, if the amount is too large, the moldability decreases, and the air permeability of the obtained stretched film decreases. Component D (copolymer of ethylene and cyclic aminovinyl compound)
In the case where is blended, the amount of the cyclic aminovinyl compound unit in the copolymer is 0.05 to 5% by weight, preferably 0.1 to 3% by weight, particularly preferably 0.1 to 3% by weight based on the total amount of the resin composition.
An amount of 1 to 1% by weight of component D is used. If the proportion of the cyclic aminovinyl compound unit in the resin composition is too small, the weather resistance becomes insufficient or the effect of improving the printability is reduced. On the other hand, if it exceeds the above range, the film strength will be insufficient, and the practicality will be poor.

[III] Production of Filler-Containing Resin Composition (1) Blending The filler-containing resin composition of the present invention can be prepared by the same method as that for producing a normal resin composition, and the ethylene of the component A has 3 or more carbon atoms. Α-olefin copolymer and component B have an average particle size of 10 μm or less and a bulk density of 0.1 to 0.7 g / cm ^3.
And a dispersant of component C, and a copolymer of ethylene and a cyclic aminovinyl compound as component D, if necessary. Specifically, each component is mixed well with a Brabender such as a Henschel mixer, and if necessary, other additives are further added to this mixture and mixed, and a twin-screw kneading extruder is used.
After melting and kneading using a Banbury mixer, a kneader blender or the like, the mixture is usually formed into pellets by a commonly used method. The order of blending each component is basically arbitrary, but when blending component D, component A
It is preferable to mix component B after mixing component D. However, the masterbatch of component B and component D, or component A and component B,
Can also be blended.

(2) Other Additives In addition to the above-mentioned dispersants, auxiliary filler components generally used for resin compositions, such as antioxidants, may be added to the filler-containing resin composition used in the present invention. A heat stabilizer, a light stabilizer, an ultraviolet absorber, a neutralizing agent, a lubricant, an antifogging agent, an antiblocking agent, an antistatic agent, a slip agent, a coloring agent, and the like may be added. Resins and rubber components such as ethylene / α-olefin copolymer, high-pressure low-density polyethylene, high-density polyethylene, polypropylene, polybutene, ethylene / vinyl acetate copolymer other than component A do not significantly impair the effects of the present invention. A range can be used in the present invention.

[IV] Stretched Film The filler-containing stretched film can be produced by melt-extruding the filler-containing resin composition of the present invention by a conventional method and then uniaxially stretching. As a method for producing the stretched film, a general method for forming a stretched film, for example, inflation molding or T-die molding can be employed. The resin composition of the present invention is melt-extruded at a temperature equal to or lower than the melting point, and is monoaxially or biaxially stretched to obtain a stretched film. As the method of uniaxial stretching, flat roll stretching, oven stretching, tube stretching, etc., and in biaxial stretching, flat tenter stretching, tube inflation stretching, mandrel stretching, etc. may be employed. it can. The stretching ratio is 1.2 to 6 times, preferably 1.2 to 4 times.

Observation of the cross section in the longitudinal direction of the stretched film of the present invention reveals that a large number of voids are finely and uniformly dispersed as compared with those formed from the conventional filler-containing resin composition. Only a small area (Fig. 1
And 2). When the range occupied by the resin alone is wide, or when voids do not exist continuously from the front surface to the back surface of the film, the air permeability of the film becomes very poor, but this is not the case with the stretched film of the present invention. Therefore, the stretched film according to the present invention, for example, disposable diapers, sanitary products, films for hygiene materials such as medical clothing,
For rain protection sheet of wood building, protection sheet for trees, etc.
It can be suitably used.

An index indicating that the stretched film of the present invention has good air permeability includes a large void area ratio of the stretched film. The void area ratio is the machine direction (MD) of the stretched film.
Mean void area per 100 μm 2 of the film cross section. The measurement of the average void area is performed as follows. The filler-containing composition is melt extruded, and the stretched film is formed into an appropriate size (for example, 10 mm ×
2 mm), and this is embedded in an epoxy resin. The obtained sample is cooled to about −2.3 ° C., and a cross section of the film in the machine direction (MD direction) is cut vertically. Platinum cutting surface
Coat with palladium to a thickness of 15-20 nm. The coated surface is observed and photographed with a scanning electron microscope at an acceleration voltage of 10 Kv and at a magnification of 2000 times. From the obtained photograph, the void area in 10 μm × 10 μm (100 μm ² ) is counted, and this is repeated about 6 to 10 times in different places, the average value is obtained, and the value is defined as the void area ratio.

[0037]

EXAMPLES The present invention will be described more specifically with reference to experimental examples including examples and comparative examples. [I] Measurement and evaluation methods of physical properties Measurement and evaluation of physical properties in Examples and Comparative Examples were carried out by the following methods. (1) Measurement of physical properties (a) MFR: compliant with JIS-K7210 (b) Density: compliant with JIS-K7112

(C) Measurement of elution curve: Temperature rising elution fractionation in the present invention (Temperature Rising Elution Fraction)
The peak of the elution curve due to ation: TREF) is obtained by completely dissolving the polymer once at a high temperature, then cooling to form a thin polymer layer on the surface of the inert support, and then continuously or stepwise increasing the temperature. To collect the eluted components,
The concentration is continuously detected, and the composition distribution of the polymer is measured by the peak of a graph (elution curve) drawn by the elution amount and the elution temperature.

The elution curve was measured as follows. Cross sorter (Mitsubishi Yuka Co., Ltd.)
And CFC T150A) manufactured according to the measurement method of the attached operation manual. This cross sorter,
A temperature rising elution fractionation (TREF) mechanism for fractionating a sample by utilizing the difference in dissolution temperature, and a size exclusion chromatograph (Size Exclusi) for further fractionating fractionated fractions by molecular size.
on Chromatography (SEC) is a device connected online.

First, a sample (copolymer) to be measured was dissolved in a solvent (o-dichlorobenzene) at a concentration of 4 mg /
The solution is dissolved at 140 ° C. so as to obtain a volume of 100 ml, and the solution is injected into a sample loop in the measurement device. The following measurements are performed automatically according to the set conditions. The sample solution held in the sample loop is separated using the difference in dissolution temperature.
0.4 ml is injected into a REF column (a stainless steel column packed with glass beads as an inert carrier and having an inner diameter of 4 mm and a length of 150 mm attached to the apparatus). Next, the sample is cooled at a rate of 1 ° C./min from a temperature of 140 ° C. to a temperature of 0 ° C. and coated on the inert carrier. At this time,
A polymer layer is formed on the surface of the inert carrier in the order from the highly crystalline component (the one that easily crystallizes) to the low crystalline component (the one that hardly crystallizes). After the TREF column is kept at 0 ° C. for another 30 minutes, 2 ml of the dissolved component at a temperature of 0 ° C.
At a flow rate of 1 ml / min from a TREF column to an SEC column (3 AD80M / S manufactured by Showa Denko KK). While fractionation by molecular size is being performed at SEC,
In the TREF column, the temperature is raised to the next elution temperature (5 ° C.)
Hold at that temperature for about 30 minutes. The measurement of each elution section by SEC was performed at intervals of 39 minutes. The elution temperature is raised stepwise at the following temperature. 0, 5, 10, 15, 20,
25, 30, 35, 40, 45, 49, 52, 55, 5
8, 61, 64, 67, 70, 73, 76, 79, 8
2,85,88,91,94,97,100,102,
120, 140 ° C

The solution fractionated by the molecular size in the SEC column was measured for absorbance in proportion to the concentration of the polymer using an infrared spectrophotometer attached to the apparatus (wavelength: 3.42 μm, detected by stretching vibration of methylene). A chromatogram of the elution temperature category is obtained. Using the built-in data processing software, the base line of the chromatogram of each elution temperature section obtained by the above measurement is drawn and processed. The area of each chromatogram is integrated and an integrated elution curve is calculated. Also,
This integral elution curve is differentiated with respect to temperature to calculate a differential elution curve. The drawing of the calculation result is output to the printer.
The plot of the output differential elution curve shows the elution temperature of 1 on the horizontal axis.
89.3 mm per 00 ° C., differential amount on the vertical axis (total integrated elution amount is set to 1.0, and the change amount at 1 ° C. is defined as the differential amount)
The measurement was performed at 76.5 mm per 0.1. Next, the peak height (mm) of this differential elution curve is reduced to a half height width (mm).
The value divided by was defined as H / W.

(D) Q value: Measured using Size Exclusion Chromatography (SEC) under the following measurement conditions, and the weight average molecular weight /
The Q value was determined from the number average molecular weight. In addition, a universal calibration curve was created with monodisperse polystyrene, and calculated as the molecular weight of linear polyethylene. Model: Waters Model 150C GPC Solvent: o-dichlorobenzene Flow rate: 1 ml / min Temperature: 140 ° C. Measurement concentration: 2 mg / ml Injection volume: 200 μl Column: AD80M / S, 3 pieces, manufactured by Showa Denko KK

(E) Average particle size: determined by Coulter counter method (dispersion method: 28 KC ultrasonic wave for 5 minutes, using 0.01% sodium hexametaphosphate). (F) Bulk density: in accordance with JIS-K5101 (g) Boiling n-hexane extraction amount: 5 g of a film extruded to a film thickness of 30 μm at 200 ° C. by air-cooled inflation molding was placed in a cylindrical filter paper, and then 200 ml.
With a Soxhlet extraction device injected with normal hexane,
Extract at boiling point for 8 hours. After drying the cylindrical filter paper with a vacuum dryer for 60 minutes, the weight loss is measured.

(2) Evaluation method (a) Tensile strength and elongation: in accordance with ASTM-D882-67 (b) Measurement of elastic recovery: The film was measured for a distance between gauges of 10
The test piece was punched into a dumbbell shape having a width of 5 mm and a width of 5 mm for a tensile test. Elastic recovery = [{distance between gauges after 100% two-cycle stretching (mm) −10 mm｝ ÷ 10 mm] × 100 (%) (c) Moisture permeability: conforming to JIS-Z0208 (d) Weather resistance: The film test piece was irradiated with ultraviolet light under the conditions, and the tensile strength of the irradiated piece was measured. The time required for the elongation at the start of the weathering test to be halved (h
r) was determined. Model: Sunshine weather meter manufactured by Suga Test Instruments Temperature: Adjusted to 63 ± 3 ° C using black panel Light source: UV irradiation through glass filter Cycle: Total 60 minutes, Water 12 minutes, None 48 minutes (e) Printability: The wetting tension was measured. Measurement method is JIS
According to K6768 (f) Void area ratio: Performed by the method described above.

[II] Experimental example Example 1 Production of component A (ethylene-α-olefin having 3 or more carbon atoms)
(Copolymer) The catalyst was prepared by the method described in JP-A-61-130314. That is, to 2.0 mmol of the complex ethylene-bis (4,5,6,7-tetrahydroindenyl) zirconium dichloride, methylalumoxane (manufactured by Toyo Stoffer Co., Ltd.) was added 1,000 times as much as the above complex, and 10 liter of toluene was added. To prepare a catalyst solution, which was polymerized by the following method. A mixture of ethylene and 1-hexene was added to a 1.5-liter stirred autoclave-type continuous reactor in which the
0% by weight, and the pressure in the reactor is set to 1,0.
The reaction was performed at a temperature of 160 ° C. while maintaining the pressure at 00 kg / cm ² . After the reaction was completed, the MFR was 3.3 g / 10 min, the density was 0.905 g / cm ³ , and the amount of boiling n-hexane extracted was 1
0.7% by weight, Q value of 2.0, one peak of TREF elution curve, peak temperature of 62 ° C., H / W of the peak temperature is 4, elution amount at 50 ° C. is 12% by weight %
(1-hexene content: 16% by weight).

Production of Filler-Containing Resin Composition The ethylene / α-olefin copolymer of component A and calcium carbonate having an average particle size of 1.0 μm and a bulk density of 0.4 were used as component B. First, component A and component B are mixed with a Henschel mixer so that component A: component B = 40: 60% by weight, and 3 parts by weight of glyceryl triricinoleate (castor oil) is added and mixed, followed by biaxial kneading. Using an extruder (screw diameter 65 mm), the mixture was extruded at a temperature of 200 ° C. to obtain pellets of each composition.

The pellets made from formed form this filler-containing resin composition, by the following method was subjected to a molding process. The pellets are extruded into a film at a temperature of 230 ° C. using an extruder (screw: diameter 40 mmφ, L / D: 24) and a T-die (die width: 300 mm, lip width: 1.2 mm), and this is hot-stretched in a short section. The film was uniaxially stretched with a roll at a stretching temperature of 85 ° C and a stretching ratio of 2 to produce a breathable film having a thickness of about 20 µm or 〜30 µm. This film was evaluated. Table 1 shows the results.

Examples 2 to 3 A resin composition was prepared in the same manner as in Example 1 except that components A, B and other components having the physical properties shown in Table 1 were used. . This was molded and evaluated. Table 1 shows the obtained evaluation results.

Comparative Examples 1 to 3 Molding was performed in the same manner as in Example 1 except that an ethylene / α-olefin copolymer having the physical properties shown in Table 1 manufactured using a Ziegler catalyst was used as the component A, and evaluation was performed. did. Table 1 shows the obtained results.

[0050]

[Table 1]

Example 4 Component D (Ethylene / cyclic aminovinyl compound copolymer)
In a stirred autoclave-type continuous reactor, 4-acryloyloxy-2, dissolved in ethylene and ethyl acetate was added.
2,6,6-Tetramethylpiperidine was continuously supplied as a catalyst together with tert-butyl peroxypivalate dissolved in normal hexane, and the polymerization pressure was 2,0.
The copolymerization was performed under the conditions of 00 kg / cm ² and a polymerization temperature of 200 ° C. The MFR of the obtained copolymer was 2.7 g / 10
The content of 4-acryloyloxy-2,2,6,6-tetramethylpiperidine unit is 7.0% by weight (0.99%).
Mol%).

Preparation of Filler-Containing Resin Composition The same components A and B as used in Example 1 were used, and glyceryl trilysylate (castor oil) and component D were used as component C. 40 parts by weight of the component A, 60 parts by weight of the component B, and 3.3 parts by weight of the component C were mixed using a Henschel mixer, and 3 parts by weight of the above dispersant was added thereto and mixed. (Screw diameter 65mm)
To obtain pellets containing 0.22% by weight of 4-acryloyloxy-2,2,6,6-tetramethylpiperidine units in the composition.

Molding (Production of Stretched Film) Pellets comprising the filler-containing resin composition were molded by the following method. The pellets are extruded into a film at a temperature of 230 ° C. using an extruder (screw: diameter 40 mmφ, L / D: 24) and a T-die (die width: 300 mm, lip width: 1.2 mm), and this is hot-stretched in a short section. The film was uniaxially stretched with a roll at a stretching temperature of 85 ° C. and a stretching ratio of 3 to produce a breathable film having a thickness of about 35 μm. This film was evaluated. At the time of molding, the presence or absence of fuming and dirt on the chill roll were observed by visual inspection. Table 2 shows the results.

Example 5 A resin composition was obtained in the same manner as in Example 4, except that the components A, B and other components having physical properties shown in Table 1 were used. This was molded and evaluated. Table 2 shows the obtained evaluation results.

Comparative Examples 4 to 6 Using an ethylene / α-olefin copolymer having the physical properties shown in Table 2 produced using a Ziegler catalyst as the component A, according to the formulation shown in Table 2, the same as in Example 4 And the obtained stretched film was evaluated. Comparative Example 5
Is a compound in which benzotriazole is blended in place of the component C as a weathering agent, and Comparative Example 6 is not blended. Table 2 shows the obtained results.

[0056]

[Table 2]

[0057]

As described above, the stretched film of the present invention has excellent elastic recovery properties, strength, texture, weather resistance, good stretchability, and excellent breathability. It is useful as a film material for sanitary materials such as sanitary articles and clothing for clothing.

[Brief description of the drawings]

FIG. 1 is an electron micrograph (2000 times) showing a cross-sectional structure of a stretched film (stretching ratio = 3) produced from the filler-containing resin composition described in Example 1.

FIG. 2 is an electron micrograph (× 2000) showing a cross-sectional structure of a stretched film (stretching ratio = 3) manufactured from the filler-containing resin composition described in Comparative Example 3.

[Explanation of symbols]

 1 Filler 2 Void

Continued on the front page (51) Int.Cl. ⁶ Identification code FI B29K 105: 16

Claims (3)

[Claims] 1. A composition containing the following components A and B, and the mixing ratio thereof is based on the total amount of both components A and B.
20% to 80% by weight of component A, 80% to 20% by weight of component B
A melt-extruded filler-containing resin composition, and uniaxially or biaxially stretched to form a breathable stretched film. Component A: a copolymer of ethylene having the following properties (a) to (c) and an α-olefin having 3 or more carbon atoms: (a) MFR of 0.01 to 20 g / 10 min (b) Density 0.935 g / cm ³ or less (c) The amount of elution at 50 ° C. (Y: wt% based on the total amount of component A) by temperature rise elution fractionation (TREF) satisfies the following condition: The density (D) of component A is When less than 0.91 g / cm ³ , Y ≦ −4500D + 4105 (where Y ≦ 100) When the density (D) of the component A is 0.91 g / cm ³ or more, Y ≦ 10 Component B: average particle diameter Is 10 μm or less, and the bulk density is 0.1 to
Particulate inorganic filler 0.7 g / cm ³ 2. The composition according to claim 1, further comprising 0.1 to 15 parts by weight of a dispersant for the particulate inorganic filler as Component C.
The breathable stretched film according to the above. Further, as the component D, ethylene and the following general formula (I): (Wherein R ¹ and R ² represent a hydrogen atom or a methyl group,
R ³ represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms)
The copolymer with a cyclic aminovinyl compound represented by the formula (1), wherein the amount of the cyclic aminovinyl compound unit in the copolymer is 0.05 to 5% by weight based on the total amount of the resin composition. Or the breathable described stretched film of 2.