JPS58180541A - Polyolefin composition for production of biaxially oriented film - Google Patents

Abstract

PURPOSE:To provide the titled compsn. giving a biaxially oriented film having improved transparency and blocking resistance, by blending a specified anti- blocking agent with a polyolefin. CONSTITUTION:An aq. soln. of CaCl2 and/or a lime milk slurry are/is added to a slurry contg. zeolite having an average particle size of 0.5-5mum to obtain a Ca-contg. zeolite slurry, to which CO2 gas or calcareous water is then added to effect carbonatation, whereby there can be obtd. an anti-blocking agent consisting of fine composite powder which has a primary particle size of 0.1- 5mum and in which fine CaCO3 is deposited on zeolite particles. 0.01-5wt% anti-blocking agent is blended with a polyolefin having an MI of 0.01-100g/ 10min such as PP.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a zaryolefin composition for knee-stretched films containing a particularly high olide value, the object of which is to significantly improve transparency and anti-blocking properties. An object of the present invention is to provide a biaxially oriented polyolefin film.

24111-Stretched polyolefin film, especially its Je
Lipropylene film is widely used not only as an industrial material but also as a material for kettle noodles.

However, as is well known, this polyolefin film is sticky and prone to boot-king (which not only impairs workability in film manufacturing and high-level processing, but also Troubles tend to occur when using film for packing or packaging.Therefore, this film is usually treated with anti-blocking tin salt, and the typical anti-blocking agent is fine powder*mm or calcium carbonate. known and used.

On the other hand, excellent transparency is required as the crystalline g1% property of polyolefin films, but this transparency and blocking resistance are contradictory characteristics. For this purpose, it is better to increase the amount of ilt added, but the transparency will decrease accordingly.The conventional additives for modification to effectively satisfy t-X are Both had shortcomings.

Recently, however, it has been proposed to add zeolite powder to polypropylene in order to satisfy both the a1 property and the blocking resistance. (Special Publication WB!Co/4/34I) This offite powder is a natural product or a granulated synthetic product that has been mechanically pulverized into a very fine powder, and is different from conventional clay or fine powder. The transparency and blocking resistance are relatively improved compared to fit!II.

The present inventors have found that zeolite and polypropylene have similar layer refractive indexes to light, so when used as a 1 mm zeolite agent, they have the advantage of not essentially impairing transparency. I tried many experiments, but
Zeolite is a type of aluminosilicon III salt, and it is extremely versatile depending on its chemical composition and crystal form, and there are also natural products and synthetic products, and when used as an antiblocking agent, it is 1. As can be seen in the difference between the natural product and the synthetic product, it was found that the transparency and anti-blocking properties of the film had a miraculous paran Φ, which caused the re-attribution to suffer. In particular, mechanically pulverized particles inevitably have a wide particle size distribution, uneven particle surfaces, and rough fractured surfaces, which are major drawbacks. Therefore, even if the particle size is classified to m, it will not solve the problem essentially and will only increase the yield.In this way, all conventional anti-blocking agents are based only on the particle size of the ground powder. The mainstream approach was to focus on
We conducted intensive research on the anti-blocking performance of the film while taking advantage of the advantages of zeolite, and found that the overall relationship between particle crystallinity, shape, surface grain, and corporate culture distribution has a great influence, and that there are special products with excellent performance. Zeolite [I learned a lot and was able to complete the invention.

That is, the present invention relates to a polyolefin composition for two-wheel stretched films, which is made by blending a polyolefin with a composite powder in which fine calcium carbonate is deposited on zeolite particles as an antiblocking agent. Generally, "zeophyte" is a general term for crystalline aluminosilicate having a unique three-dimensional structure, but 5102/Aj20. Many distributions are known, depending on the molar ratio of and crystal structure. The zeolite applied to this J[ is used as a core material and is not particularly limited as long as it is a fine particle, and may be either a natural product or a synthetic product, or may be a synthetic product. However, there are few impurities (,
In addition, synthetic products are preferable because the particle size is easily compromised.

On the other hand, AM zeolite is easy to supply and receive from an industrial and quality perspective, and is suitable for use as a core material.

The heptadophite is usually a sulfurium zeolite, but there is also a metal-substituted layer zeolite in which sodium is ion-exchanged with other metal ions, and any of these may be used. for example,
Calcium Afize 4 Tite is particularly preferred. The zeonoid used as the core material must be fine particles, and the average particle diameter determined from the particle size distribution by the constant light transmission method must be in the range of 0.3-j Jlm. Sharp ones are suitable for writing.

The antiblocking agent in the present invention is a fine powder* of a combination of theorite and calcium carbonate, which uses the above-mentioned zeophyte particles as a core material and has fine calcium carbonate deposited on the surface of the particles.

The primary particles of this fine powder are found to be substantially in the m range of o, i to j IJm, and sometimes υ, S-
An axis of reference μm is preferred. v4 Qualitative means that even if some particles outside m1i1 were detected by electron microscopic observation, the majority of primary particles could be detected within the range. In this case, zeophyte and calcium carbonate are preferably i;o,os~/:l;
o, t~/: Surrounded by 1@ of O, S.

This is because the above-mentioned items in @1 effectively provide a satisfactory combination of the contradictory film properties of polyolefin film pronking resistance and brightness, and also provide a satisfactory effect on the polyolefin film. This is because the properties are excellent in non-linearity regardless of the amount added.

The above-mentioned zeolite and calcium carbonate composite is a calcium-containing zeolite obtained by combining a typical zeophyt slurry used as a core material with an aqueous calcium chloride solution and/or a milky lime slurry, and adding it to a free mixture of gas or carbonated water. C#- by adding t- and carbonation.

When carbonating the zeolite slurry, it is preferable to apply shearing force using a pre-V homogenizer or add a desired dispersion iA to sufficiently disperse the slurry into secondary particles. In carbonation, either II heating or 4J heating may be used, and although there is no particular temperature limitation, it is preferable to carry out the reaction at a pH of around 10.

Industrially, it is advantageous to ion-exchange sodium Aal heptaolide and calcium A-deficient zeotide, add appropriate milk of lime, and then carbonate the mixture as it is.
It is also particularly excellent as an anti-blocking agent.

Through this reaction, 111 md is formed on the surface of the zeolite particles.
Calcium is deposited like a shark.

Therefore, in the resulting zeolite-calcium carbonate aggregate, fine calcium carbonate is contained on the surface of the zeolite particles, either as a substantive precipitate or as a loose part.

On the other hand, the polyolefin that can be applied to the present invention is not particularly limited as long as it has the ability to form a transparent, crystalline, self-supporting film;
A crystalline homoelectrolyte or a crystalline comonomer of two or more types of α-olefins with a low degree of maple, specifically polyenale/, polypropylene, polydarmethylbe/ten-11, tyrene-propylene random or block copolymer Examples include ethylene-propylene-butene copolymer, ethylene-propylene/hexene copolymer, and the like.

Among these, a heavy metal body of polypropylene or zoropylene, the majority of which is propylene, and another α-olefin is preferred, and a propylene rod containing 0 to 6% ethylene haze is preferred.

Further, these polyolefins are crystalline and have an ink index (1) of 4yo or more, particularly 60 or more, especially 90 or more. Furthermore, it is used as long as it can be molded, but usually melt 70
-Rate (, +FR) is 0.0 / ~ / 001/1
0' minutes, especially 0. / to so i / / o minutes, especially o, s to / o lio minutes are preferred.

The amount of the zeolite-calc/rum carbonate complex to be added as an anti-blocking agent to such polyolefin is as follows:
Although there is no single C depending on the purpose of the film, the type of polyolefin, the type of doll metal body, etc., in many cases polyolein IO is used.

A suitable amount is 0.07 to 3 parts per part of D.
J,/deuteriis is preferred. The reason for this is Fll111
If it is less than 1i11, the S stimulation is small, so the source of the target young fruit is insufficient, and the degree of wt to be blended into polio and fins and dispersed uniformly is low. On the other hand, if the upper limit m is exceeded, the film transparency fraI
In addition, the blocking resistance does not improve in spite of the added filter, and the film's stretchability also decreases.

In the present invention, the additives used in lyolefin include antioxidants, stabilizers, starting aids,
It is of course possible to use coloring agents and anti-banding agents, but zeolite often has the effect of enhancing the properties of these additives, so it is more preferable to use 31.
m-buttons may be recognized.

The polyolefin composition according to the present invention can be prepared by a conventional method.
By stretching, a film with good workability, transparency, and anti-blocking properties can be produced.

In particular, the film of the present invention exhibits less surface roughness caused by rubbing between films than a film made using finely divided zeophyte obtained by pulverization or non-compounded zeolite as an anti-bronching agent. With hot water (
It has a unique characteristic of being less scratchy.

Examples of the present invention will be explained in detail below.

The average particle size is O, Sμm) IJum Afi zeolite is used as the core material, and the particles are made of fine calcium carbonate gold.
aLI! Prolagging inhibitor tmllll by depositing in I
I was angry. The method and physical properties are shown in Table 1.

Zeophyto-calcium carbonate *&ni powder A obtained in L.
A polyglopylene composition was added to the polyglopylene composition in the following manner as an anti-blocking agent, and then a two-wheel stretched film was obtained. When the physical properties of the film were evaluated using a certain method, the following results were obtained.

#- of polypropylene group IiL book is ASTM D/2J
The melt flow rate according to E is /,? 9/'70 minute polypropylene tree N100 weight flk product, Kotsu 6-di-t-butyl-p-cresol 0 as an anti-oxidation agent.
．． 10 parts of IL, tetrakis[methylene-J-(3,3
-Gt・-Butiluda-1 Idroikai Diphenol]
0.101% of Tan, 0.101 parts of sterine powder as a hydrochloric acid catch agent, parts by weight of OS, and parts by weight of olide-charcoal-brewed calcium powder* as an anti-gronking agent. or), /
1 mm of the product was added, and after warming, it was made into pellets.

This pellet [a pot made into a sheet shape using an extruder, a vertical blade v@j bond, and a stretched film of JOμm =IIIIl stretched film t-m
Built.

Regarding these biaxially stretched films, the transparency, blocking property, and scratch property were kept constant.

Transparency was determined in accordance with AS'rM D-1003 using film fIc: m'Iii. The blocking property was measured by placing a sickle between two glass plates so that the contact area of the two films was 1 ocs, 5o1)7
7 days in an atmosphere of tIO℃ over cm2 #rmt*, using a Schopper experience test, the withdrawal rate so
It was peeled off at a rate of 0 mm/min, and the finished load VL was read and evaluated. For scratch resistance, the biaxially stretched film was fixed on a GTX plate, and the other side of the contact plate was 40 ell”
A fixed amount of film was placed on a boat, and the film was rubbed with a load of 39 times, j times, and evaluated based on the difference in transparency before and after rubbing. The smaller this value is, the better the scratch resistance becomes.

Table 1 Example - An anti-gronking agent was prepared by using sodium AJll zeolite with a semiconstricted particle diameter of 1/Arm as a core material and washing the surface of fine J# calcium particles in a bath. Its strength and physical properties are shown in Table 7 of Jl.

#8J A borinopropylene composition was prepared using the above-mentioned zeolite-calcium carbonate polymer powder as a blockfish prevention agent, and then a knee-stretched film was prepared under the same conditions as jI [1 blind/]. About the film I got [
- When the collar was evaluated, the results were disappointing.

Table q Table Jt Yield N/~3 Powdered silica was added as an anti-blocking agent to the sodium ha zeolite tank used in Examples 1 and 2 before the expedient treatment of the bonds used in Example 1, and the mixture was treated under the same conditions as Example 1. A biaxially stretched film was obtained. When the film was similarly evaluated, the results shown in the lls table were excellent.

Patent applicant: Nippon Chemical Industry Co., Ltd. Dai Hanawa person So I way collapse [1shi-go J'

Claims (1)

[Scope of Claims] (1) A two-wheel stretched film made by blending polyolefin with a fine powder obtained by depositing fine Cal/Umum on zeolite particles as an anti-blocking agent. Polyolefin composition for use. +2J Polyolef ~ 17 is polypropylene or a copoly Y- of this and other α-neoleph 1 i) 2 s of the patent claim where 'PH1 is specified.
Polyolefin composition for stretched film. (3) The polyolefin composition for a stretched motorcycle film according to item 1, wherein the zeolite is mixed with Afi zeophyt. I - The combined fine powder is characterized in that the primary particles as determined by electronic observation are substantially in the range of o, i to S μm. Polyolefin composition. 151 I! The combined mold wheel is characterized in that the weight ratio of zeophyte and calcium carbonate is in the range of i: o, o s to l: 10. Polyolefin composition. (-The combined powder is 0.07 to 5% relative to the polyolefin.
Claims: JJ4. The polyolefin composition for biaxially oriented films as described in Item No. 3 or Item I.