JP2001162667A - Resin guide device of inflation molding apparatus and method for producing film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a resin guide device of an inflation molding apparatus which can obtain a film having a good appearance with reduced wrinkles and thickness nonuniformity and a method for producing the film. SOLUTION: The resin guide device 3 has a pair of guide members 6a, 6b arranged to be tapered on the sides of a pair of take-up rolls 4a, 4b. The members 6a, 6b have the first and second frames 7, 9 arranged at a prescribed interval and thin permeable sheets 8 stuck to the frames 7, 9. When bubbles B, which were extruded from an inflation molding die 2 and inflated, are brought into contact with the sheets 8, the sheets 8 wrap up the bubbles while being pushed outside by the bubbles B. Air is introduced into the sheets 8 from the outsides of the guide members 6a, 6b, and the bubbles B are cooked gradually.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resin guide device and an inflation molding device in an inflation molding device for guiding a molten resin extruded into a tubular shape from an inflation molding die to a pair of take-off rolls while cooling the resin. The present invention relates to a method for producing a film by using the film.

[0002]

2. Description of the Related Art Conventionally, when a film is produced by inflation molding, first, a molten resin is extruded into a cylindrical shape from an annular slit provided in an inflation molding die, and air or the like is introduced into the cylindrical resin. Is blown to expand the resin and cool the cylindrical resin. Then, the expanded cylindrical resin is folded flat by a pair of stabilizers arranged to be tapered with respect to the resin extrusion direction, and the flat resin is taken up by a pair of take-off rolls. Further, it is wound up by a winding roll. In such an inflation molding method, in order to stably cool the expanded cylindrical resin,
An air ring that blows a gas such as air onto a cylindrical resin is generally used.

[0003]

According to the above-mentioned prior art, as a resin, for example, polyethylene (PE) or polypropylene (PP), solidification by cooling occurs relatively slowly, the elasticity at the time of solidification is relatively low, and the tensile elongation is low. It is very effective when a general-purpose plastic having a relatively large is used.

On the other hand, in recent years, expectations have been growing for engineering plastic films having high heat resistance, high elastic modulus, and low elongation, and demands for inflation molding capable of obtaining such films relatively inexpensively have increased. ing. However, engineering plastics have the property of being easily cooled and solidified remarkably compared to general-purpose plastics.Forced cooling with the above-mentioned air ring etc. causes cooling shrinkage and cooling unevenness,
In some cases, wrinkles and thickness unevenness occurred, and the appearance of the film was significantly impaired.

An object of the present invention is to provide a resin guide device in an inflation molding apparatus and a method for producing a film, which make it possible to obtain a film having good appearance with less wrinkles and thickness unevenness.

[0006]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention relates to a resin for an inflation molding apparatus, wherein a molten resin extruded into a tubular shape from an inflation molding die is guided to a pair of take-off rolls while cooling. A guide device, comprising a pair of guide members that are disposed so as to be tapered on a pair of take-off roll sides and fold a cylindrical resin into a flat shape, and a portion of each guide member where the cylindrical resin contacts. , Characterized by being constituted by a member having air permeability.

In the present invention thus constructed, when a gas such as air is introduced into the molten resin extruded into a cylindrical shape from the inflation molding die, the cylindrical resin expands, and the expanded cylindrical shape is expanded. When the resin contacts the air-permeable member of the pair of guide members, the air-permeable member wraps the resin while being pressed by the internal pressure of the cylindrical resin, and in that state, the cylindrical resin gradually It is folded flat. At this time, the resin is cooled by appropriately entering air into the air-permeable member from outside the pair of guide members. Therefore, since it is not necessary to perform forced cooling by an air ring or the like, it is possible to obtain a film having a good appearance with less wrinkles and thickness unevenness in inflation film formation of a liquid crystalline polymer, for example, so that stable film formation can be performed. become.

[0008] Preferably, the member having air permeability is made of AS
Perm-Poromete conforming to TM F316
r, the air pressure was 0.02 kg when the diameter of the circular test piece used for the test was 38 mm.
/ Cm ² air permeability is 100-5000cc / s
ec. Thereby, the cylindrical resin is optimally cooled and solidified, and more stable inflation film formation can be performed.

Preferably, the apparatus further comprises a means disposed outside the pair of guide members, for blowing gas to a member having air permeability. This allows the tubular resin to be smoothly enveloped in the air-permeable member. Further, the cooling efficiency of the resin is improved.

For example, the guide member has a first frame disposed adjacent to the take-up roll and extending substantially parallel to the longitudinal direction of the take-up roll, and the first frame includes a member having air permeability. Some have been fixed.

In this case, it is preferable to provide a cooling passage in the first frame. Thus, by flowing the cooling water through the cooling passage, the cylindrical resin immediately before being taken up by the take-up roll can be cooled, and the cooling efficiency of the resin is improved.

[0012] Preferably, the guide member has a second frame disposed closer to the inflation molding die than the first frame, and the second frame includes another part of a member having air permeability. Is fixed so that it can be wound up and unwound. Thus, the vertical dimension of the air-permeable member can be changed, so that efficient inflation film formation can be performed according to the conditions such as the amount of molten resin extruded from the inflation molding die and the degree of cooling of the resin. .

[0013] The member having air permeability is a mesh, a woven cloth,
It is preferable to use any of non-woven fabrics in that a certain degree of air permeability can be secured.

In order to achieve the above object, a method of manufacturing a film according to the present invention comprises extruding a molten resin into a tubular shape from an inflation molding die and blowing a gas into the tubular resin to expand the resin. After that, the tubular resin expanded by the pair of guide members of the resin guide device is folded flat, the flattened tubular resin is taken up, and the film is formed by further winding. And

As described above, by manufacturing a film using the above resin guide device,
Since it is not necessary to perform forced cooling by an air ring or the like, it is possible to obtain a film having a good appearance with less wrinkles and thickness unevenness.

For example, a liquid crystalline polymer that exhibits optical anisotropy when melted is used as the resin. In this case, (A) a liquid crystalline polyester is used as a continuous phase as a liquid crystalline polymer from the viewpoint of moldability and performance of the obtained film.
(B) It is preferable to use a liquid crystal polyester resin composition containing a copolymer having a functional group reactive with the liquid crystal polyester as a dispersed phase. Further, as the liquid crystal polymer, (A) 56.0 to 99.9% by weight of a liquid crystal polyester, and (B) 44.0 to 0.1% by weight of a copolymer having a functional group reactive with the liquid crystal polyester. May be used.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of a resin guide device and a method of manufacturing a film according to the present invention will be described below with reference to the drawings.

FIG. 1 is a configuration diagram of an inflation molding device including a resin guide device according to the present invention. In the figure, an inflation molding apparatus 1 includes an inflation molding die 2 and an inflation molding die 2.
And a resin guide device 3 which is disposed above the resin guide device 3 and cools and flattens a molten resin (hereinafter, sometimes referred to as a bubble B) which is extruded from the inflation molding die 2 into a cylindrical shape. Bubble B
A pair of take-up rolls 4a for taking up (cylindrical film),
4b, and a winder 5 for winding the film sent from the take-up rolls 4a, 4b. FIG. 2 is a perspective view showing the resin guide device 3.

In FIG. 1 and FIG.
Are arranged so as to be tapered with respect to the extrusion direction of the molten resin, and a pair of guide members 6 for folding the bubble B flat.
a and 6b. These guide members 6a and 6b
The first is disposed adjacent to the take-up rolls 4a, 4b and extends substantially parallel to the longitudinal direction of the take-up rolls 4a, 4b.
Each has a frame 7. The first frame 7
It is composed of a metal pipe forming a cooling passage, and a hose or the like is connected to supply cooling water or the like into the first frame 7.

One end in the vertical direction of a thin (eg, 0.1 to 1.0 mm) air permeable sheet 8 having air permeability is attached to each first frame 7. This air permeable sheet 8
As the metal, resin, mesh made of inorganic fibers, etc.,
It is preferable to use a woven or nonwoven fabric. The air-permeable sheet 8 has a function of guiding the bubbles B to the guide members 6a and 6b while flattening the bubbles B, and a function of guiding the bubbles B to the guide members 6a and 6b.
Has a function of cooling the bubble B by air entering from outside. For this reason, as the air permeable sheet 8, Perm-Poro conforming to ASTM F316 is used.
In an air permeability test using a meter, when the diameter of a circular test piece used for the test is 38 mm, the air pressure is set to 0.
The air permeability at the time of 02 Kg / cm ² is 100 to 5000
A rate of cc / sec is preferable in that the bubble B can be cooled and solidified effectively. In addition, as a suitable air permeable sheet 8, a sputter sheet made of glass woven fabric (air permeability: 2)
000 cc / sec), p-aramid plain weave fabric (air permeability: 1500 cc / sec), stainless steel plain weave #
100 mesh and the like.

The other end of the air permeable sheet 8 is attached to a second frame 9 disposed closer to the inflation molding die 2 than the first frame 7 is. The second frame 9 is provided with members (not shown) such as gears and stoppers for allowing the air permeable sheet 8 to be wound and unwound. Direction) length can be changed.

Outside the pair of guide members 6a and 6b,
Air blowers 10 for blowing a gas such as air onto the permeable sheet 8 are provided. This air blower 1
No. 0 allows air or the like to be blown over the entire width direction of the permeable sheet 8, and the air volume and direction can be adjusted. It should be noted that a plurality of air blowers may be arranged outside each of the pair of guide members 6a and 6b.

The guide members 6a and 6b are, for example,
It is suspended from an upper support frame (not shown) by an arm (not shown) connected to the first frame 7. The air blower 10 is also suspended from the support frame via an arm (not shown).

Next, a method for performing inflation film formation using the inflation molding apparatus 1 including the resin guide device 3 configured as described above will be described.

First, the resin used for the inflation film formation will be described. In the present embodiment, a liquid crystal polyester exhibiting optical anisotropy when melted is used as the resin. The liquid crystal polyester referred to here is a polyester called a thermotropic liquid crystal polymer. Specifically, (1) A compound obtained by reacting an aromatic dicarboxylic acid, an aromatic diol and an aromatic hydroxycarboxylic acid. (2) Those obtained by reacting a combination of different aromatic hydroxycarboxylic acids. (3) A compound obtained by reacting an aromatic dicarboxylic acid with a nucleus-substituted aromatic diol. (4) Those obtained by reacting an aromatic hydroxycarboxylic acid with a polyester such as polyethylene terephthalate. And those which form an anisotropic melt at a temperature of 400 ° C. or lower are preferred. In addition, instead of these aromatic dicarboxylic acids, aromatic diols and aromatic hydroxycarboxylic acids, their ester derivatives may be used.

Examples of the repeating structural unit of the liquid crystal polyester include the following repeating structural units derived from an aromatic dicarboxylic acid, the following repeating structural units derived from an aromatic diol, and the following repeating structural units derived from an aromatic hydroxycarboxylic acid. However, the present invention is not limited to these. Repeating structural unit derived from aromatic dicarboxylic acid:

[0027]

Embedded image

A repeating structural unit derived from an aromatic diol:

Embedded image

[0029]

Embedded image

A repeating structural unit derived from an aromatic hydroxycarboxylic acid:

Embedded image Heat resistance, mechanical properties, particularly preferred liquid crystal polyester from the balance of workability,

Embedded image More preferably, the repeating structural unit comprises at least 30
It contains at least mol%. Specifically, the combination of repeating structural units is preferably any one of the following (I) to (VI).

[0031]

Embedded image

[0032]

Embedded image

The production methods of the liquid crystal polyesters (I) to (VI) are described, for example, in JP-B-47-47870, JP-B-63-3888, JP-B-63-3891, and JP-B-56-18016. JP-A-2-515
No. 23, and the like. Of these, a combination of (I), (II) or (IV) is preferable, and a combination of (I) or (II) is more preferable.

In the field where high heat resistance is required in the present invention, the liquid crystal polyester of the component (A) contains 30 to 80 mol% of the following repeating unit (a ′) and 0% of the repeating unit (b ′). -10 mol%, repeating unit (c ') is 1
A liquid crystal polyester having 0 to 25 mol% and a repeating unit (d ') of 10 to 35 mol% is preferably used.

[0035]

Embedded image (In the formula, Ar is a divalent aromatic group.) In the field of the present invention, from the viewpoint of environmental problems, etc., in fields where easiness of disposal such as incineration after use is required, each of the fields listed above is required. Among the preferred combinations in the field to be used, liquid crystal polyesters in particular, which are combinations of elements consisting only of carbon, hydrogen and oxygen, are particularly preferably used.

The component (B) used in the liquid crystal polyester resin composition is a copolymer having a functional group reactive with the liquid crystal polyester. The functional group reactive with the liquid crystal polyester is not particularly limited as long as it has reactivity with the liquid crystal polyester, and specific examples include an oxazolyl group, an epoxy group, and an amino group. Preferably, it is an epoxy group. The epoxy group or the like may be present as a part of another functional group, and such an example includes a glycidyl group.

In the copolymer (B), the method for introducing such a functional group into the copolymer is not particularly limited, and a known method can be used. For example, at the stage of synthesizing the copolymer, it is possible to introduce the monomer having the functional group by copolymerization, or it is also possible to graft copolymerize the monomer having the functional group to the copolymer. It is.

As the monomer having a functional group reactive with the liquid crystal polyester, in particular, a monomer containing a glycidyl group, an unsaturated glycidyl carboxylate and / or unsaturated glycidyl ether is preferably used.

Specifically, examples of the unsaturated glycidyl carboxylate include glycidyl acrylate, glycidyl methacrylate, diglycidyl itaconate, triglycidyl butenetricarboxylate,
Glycidyl p-styrenecarboxylate and the like can be mentioned. As unsaturated glycidyl ethers,
For example, vinyl glycidyl ether, allyl glycidyl ether, 2-methylallyl glycidyl ether, methacryl glycidyl ether, styrene-p-glycidyl ether and the like are exemplified.

The unsaturated carboxylic acid glycidyl ester is
Preferably a general formula

[0041]

Embedded image Wherein R is a hydrocarbon group having an ethylenically unsaturated bond and having 2 to 13 carbon atoms. The unsaturated glycidyl ether is preferably a compound represented by the general formula:

Embedded image (R is a hydrocarbon group having 2 to 18 carbon atoms which has an ethylenically unsaturated bond, X is -CH ₂ -O- or

Embedded image It is. ).

The copolymer (B) having a functional group reactive with the liquid crystal polyester preferably contains 0.1 to 30% by weight of an unsaturated carboxylic acid glycidyl ester unit and / or an unsaturated glycidyl ether unit. % Of the copolymer. The copolymer (B) having a functional group reactive with the liquid crystal polyester may be a thermoplastic resin or a rubber, or may be a mixture of a thermoplastic resin and a rubber. Good. A rubber having excellent thermal stability and flexibility of a molded product such as a film or sheet obtained by using the liquid crystal polyester resin composition is more preferable.
More preferably, the copolymer (B) having a functional group reactive with the liquid crystal polyester is a copolymer having a heat of fusion of crystal of less than 3 J / g.

The copolymer (B) preferably has a Mooney viscosity of 3 to 70, more preferably 3 to 30, and particularly preferably 4 to 25. The Mooney viscosity mentioned here is 10 according to JIS K6300.
A value measured using a large rotor at 0 ° C. Outside these ranges, the thermal stability and flexibility of the composition may be undesirably reduced.

The rubber mentioned here corresponds to a polymer substance having rubber elasticity at room temperature according to a new edition of Polymer Dictionary (edited by the Society of Polymer Science, published in 1988, Asakura Shoten).
Specific examples thereof include natural rubber, butadiene polymer, butadiene-styrene copolymer (including random copolymer, block copolymer (including SEBS rubber or SBS rubber, etc.), and graft copolymer), or The hydrogenated product, isoprene polymer, chlorobutadiene polymer, butadiene-acrylonitrile copolymer, isobutylene polymer, isobutylene-butadiene copolymer rubber,
Isobutylene-isoprene copolymer, acrylate-ethylene copolymer rubber, ethylene-propylene copolymer rubber, ethylene-butene copolymer rubber, ethylene-propylene-styrene copolymer rubber, styrene-isoprene copolymer Rubber, styrene-butylene copolymer, styrene-ethylene-propylene copolymer rubber, perfluoro rubber, fluoro rubber, chloroprene rubber, butyl rubber, silicone rubber, ethylene-propylene-non-conjugated diene copolymer rubber, thiol rubber, polysulfide Examples include rubber, polyurethane rubber, polyether rubber (for example, polypropylene oxide, etc.), epichlorohydrin rubber, polyester elastomer, polyamide elastomer, and the like. Among them, an acrylate-ethylene copolymer is preferably used, and a (meth) acrylate-ethylene copolymer rubber is more preferred. These rubber-like substances may be produced by any production method (eg, emulsion polymerization method, solution polymerization method, etc.) and any catalyst (eg, peroxide, trialkylaluminum, lithium halide, nickel-based catalyst, etc.). .

The rubber as the copolymer (B) is a rubber having a functional group reactive with the liquid crystal polyester in the above rubber. In such a rubber, a method for introducing a functional group reactive with the liquid crystal polyester into the rubber is not particularly limited, and can be performed by a known method. For example, it is possible to introduce the monomer having the functional group by copolymerization at the stage of synthesizing the rubber, or it is also possible to graft copolymerize the monomer having the functional group to the rubber.

As a specific example of the copolymer (B) having a functional group reactive with the liquid crystal polyester, a rubber having an epoxy group may be (meth) acrylate-ethylene- (unsaturated glycidyl carboxylate) And / or unsaturated glycidyl ether) copolymer rubber.

Here, the (meth) acrylate is an ester obtained from acrylic acid or methacrylic acid and an alcohol. As the alcohol, an alcohol having 1 to 8 carbon atoms is preferable. Specific examples of (meth) acrylates include methyl acrylate, methyl methacrylate, n-butyl acrylate, n-butyl methacrylate, tert-butyl acrylate, t
Examples thereof include tert-butyl methacrylate, 2-ethylhexyl acrylate, and 2-ethylhexyl methacrylate. As the (meth) acrylic acid ester, one kind thereof may be used alone, or two or more kinds may be used in combination.

Preferably, the content of the (meth) acrylate unit is 40% by weight or more and less than 97% by weight, more preferably 45-70% by weight, and the ethylene unit is 3% by weight or more
%, More preferably 10 to 49% by weight, and 0.1 to 30% by weight, more preferably 0.5 to 20% by weight, of unsaturated carboxylic acid glycidyl ether units and / or unsaturated glycidyl ether units. If the ratio is outside the above range, the resulting molded product such as a film or sheet may have insufficient thermal stability and mechanical properties, which is not preferable.

The copolymer rubber can be produced by a conventional method, for example, bulk polymerization, emulsion polymerization, solution polymerization or the like using a free radical initiator. Typical polymerization methods are described in JP-B-46-45085 and JP-B-6-45085.
No. 1-127709, pressure of 500 k in the presence of a polymerization initiator generating free radicals
g / cm ² or more and a temperature of 40 to 300 ° C.

Other rubbers usable for the copolymer (B) include acrylic rubber having a functional group reactive with liquid crystal polyester and vinyl aromatic having a functional group reactive with liquid crystal polyester. A hydrocarbon compound-conjugated diene compound block copolymer rubber can also be exemplified.

The acrylic rubber mentioned here is preferably represented by the general formula (1)

Embedded image (In the formula, R ¹ represents an alkyl group having 1 to 18 carbon atoms or a cyanoalkyl group.), A general formula (2)

Embedded image (Wherein, R ² is an alkylene group having 1 to 12 carbon atoms, R ³
Represents an alkyl group having 1 to 12 carbon atoms. ) And general formula (3)

Embedded image (Wherein R ⁴ is a hydrogen atom or a methyl group, R ⁵ is an alkylene group having 3 to 30 carbon atoms, and R ⁶ is a 1 to 20 carbon atom.
Wherein n represents an integer of 1 to 20; )) At least one monomer selected from the compounds represented by the formula (1).

Specific examples of the alkyl acrylate represented by the general formula (1) include, for example, methyl acrylate, ethyl acrylate, propyl acrylate,
Examples thereof include butyl acrylate, pentyl acrylate, hexyl acrylate, actyl acrylate, 2-ethylhexyl acrylate, nonyl acrylate, decyl acrylate, dodecyl acrylate, and cyanoethyl acrylate.

Examples of the alkoxyalkyl acrylate represented by the general formula (2) include methoxyethyl acrylate, ethoxyethyl acrylate, butoxyethyl acrylate, and ethoxypropyl acrylate. One or more of these can be used as the main component of the acrylic rubber.

As a constituent component of the acrylic rubber, an unsaturated monomer copolymerizable with at least one monomer selected from the compounds represented by the above general formulas (1) to (3), if necessary. Can be used. Examples of such unsaturated monomers include styrene, α-methylstyrene,
Acrylonitrile, halogenated styrene, methacrylonitrile, acrylamide, methacrylamide, vinylnaphthalene, N-methylolacrylamide, vinyl acetate, vinyl chloride, vinylidene chloride, benzyl acrylate, methacrylic acid, itaconic acid, fumaric acid, maleic acid, and the like. .

The preferred constituent ratio of the acrylic rubber having a functional group reactive with the liquid crystal polyester is at least one monomer 40 selected from the compounds represented by the above general formulas (1) to (3). 0.0 to 99.9% by weight, unsaturated glycidyl carboxylate and / or unsaturated glycidyl ether 0.1 to 30.0% by weight, selected from the compounds represented by the above general formulas (1) to (3). Unsaturated monomer copolymerizable with at least one monomer
３30.0% by weight. When the constituent ratio of the acrylic rubber is within the above range, heat resistance and impact resistance of the composition,
The molding processability is good and preferable.

The method for producing the acrylic rubber is not particularly limited. For example, JP-A-59-113010, JP-A-62-64809, and JP-A-3-160008
Or a well-known polymerization method described in WO95 / 04764 or the like, and can be produced by emulsion polymerization, suspension polymerization, solution polymerization or bulk polymerization in the presence of a radical initiator. .

The vinyl aromatic hydrocarbon compound-conjugated diene compound block copolymer rubber having a functional group reactive with the liquid crystal polyester is preferably (a)
Epoxidation of a rubber obtained by epoxidizing a block copolymer consisting of a sequence mainly composed of a vinyl aromatic hydrocarbon compound and (b) a sequence mainly composed of a conjugated diene compound, or epoxidation of a hydrogenated product of the block copolymer This is the rubber obtained.

The vinyl aromatic hydrocarbon compound-conjugated diene compound block copolymer or a hydrogenated product thereof can be produced by a known method.
798 and JP-A-59-133203.

As the aromatic hydrocarbon compound, for example,
Styrene, vinyltoluene, divinylbenzene, α-methylstyrene, p-methylstyrene, vinylnaphthalene and the like can be mentioned, among which styrene is preferable.
Examples of the conjugated diene compound include butadiene, isoprene, pyrrylene, 1,3-pentadiene, 3-butyl-1,3-octadiene and the like, butadiene or isoprene is preferred.

As the rubber used as the copolymer (B),
Preferably, (meth) acrylate-ethylene-
(Unsaturated carboxylic acid glycidyl ester and / or unsaturated glycidyl ether) copolymer rubber is used. The rubber used as the copolymer (B) may be vulcanized as necessary and used as a vulcanized rubber. The vulcanization of the (meth) acrylic acid ester-ethylene- (unsaturated carboxylic acid glycidyl ester and / or unsaturated glycidyl ether) copolymer rubber is performed by multifunctional organic acids, polyfunctional amine compounds, imidazole compounds, etc. However, the present invention is not limited to these.

Further, as a specific example of the copolymer (B) having a functional group reactive with the liquid crystal polyester, the thermoplastic resin having an epoxy group includes (a) an ethylene unit of 50 to 99% by weight; b) 0.1 to 30% by weight, preferably 0.5 to 20% by weight of unsaturated carboxylic acid glycidyl ester units and / or unsaturated glycidyl ether units.
% By weight, and (c) an epoxy group-containing ethylene copolymer having an ethylenically unsaturated ester compound unit of 0 to 50% by weight.

Examples of the ethylenically unsaturated ester compound (c) include vinyl carboxylate such as vinyl acetate, vinyl propionate, methyl acrylate, ethyl acrylate, butyl acrylate, methyl methacrylate, ethyl methacrylate and butyl methacrylate. Esters, α, β-unsaturated carboxylic acid alkyl esters, and the like. Particularly, vinyl acetate, methyl acrylate and ethyl acrylate are preferred.

Specific examples of the epoxy group-containing ethylene copolymer include, for example, a copolymer composed of ethylene units and glycidyl methacrylate units, a copolymer composed of ethylene units and glycidyl methacrylate units and methyl acrylate units, and ethylene units. Copolymers composed of glycidyl methacrylate units and ethyl acrylate units, and copolymers composed of ethylene units, glycidyl methacrylate units and vinyl acetate units are exemplified.

The epoxy group-containing ethylene copolymer has a melt index (hereinafter sometimes referred to as MFR. JI.
SK6760, 190 ° C, 2.16 kg load) is preferably 0.5 to 100 g / 10 min, more preferably 2 to 100 g / 10 min.
５０50 g / 10 min. The melt index may be outside this range, but the melt index is 100 g
If it exceeds / 10 minutes, it is not preferable in view of the mechanical properties of the composition, and if it is less than 0.5 g / 10 minutes, the compatibility with the liquid crystal polyester of the component (A) is inferior.

[0065] Also, the epoxy group-containing ethylene copolymer is preferably in the range stiffness modulus of 10~1300kg / cm ^2, further preferably from 20~1100kg / cm ^2. If the flexural rigidity is out of this range, the molding processability and mechanical properties of the composition may be insufficient, which is not preferable.

The epoxy group-containing ethylene copolymer is generally prepared by reacting an unsaturated epoxy compound and ethylene in the presence of a radical generator at 500 to 4000 atm and 100 to 300 ° C. in the presence or absence of a suitable solvent or chain transfer agent. It is produced by a high-pressure radical polymerization method in which copolymerization is carried out in the presence. It can also be produced by a method in which an unsaturated epoxy compound and a radical generator are mixed with polyethylene and melt-grafted and copolymerized in an extruder.

The above-mentioned liquid crystal polyester resin composition comprises:
A resin composition comprising (A) a liquid crystal polyester as a continuous phase and (B) a copolymer having a functional group reactive with the liquid crystal polyester as a dispersed phase. If the liquid crystal polyester is not a continuous phase, the gas barrier properties, heat resistance, etc. of a molded article such as a film or sheet made of the liquid crystal polyester resin composition may be significantly reduced, which is not preferable.

The details of the mechanism of the resin composition of the copolymer having a functional group and the liquid crystal polyester are not clear, but the composition between the component (A) and the component (B) of the composition is not clear. It is considered that a reaction occurs, and the component (A) forms a continuous phase, and the component (B) is finely dispersed, thereby improving the moldability of the composition.

One embodiment of the above liquid crystal polyester resin composition comprises (A) 56.0 to 99.9 liquid crystal polyester.
44% by weight, preferably 65.0 to 99.9% by weight, more preferably 70 to 98% by weight, and (B) a copolymer having a functional group reactive with the liquid crystal polyester.
The resin composition contains 0 to 0.1% by weight, preferably 35.0 to 0.1% by weight, and more preferably 30 to 2% by weight. If the content of the component (A) is less than 56.0% by weight, the gas barrier properties and heat resistance of a molded article such as a film or sheet obtained from the composition may be undesirably reduced. On the other hand, if the component (A) exceeds 99.9% by weight, the molding processability of the composition may be reduced, and the composition is expensive, which is not preferable.

As a method for producing such a liquid crystal polyester resin composition, a known method can be used. For example, there is a method in which each component is mixed in a solution state and the solvent is evaporated or precipitated in the solvent. From an industrial point of view, a method of kneading each component of the above composition in a molten state is preferred. For the melt kneading, kneading apparatuses such as a single-screw or twin-screw extruder and various kneaders which are generally used can be used. In particular, a biaxial high kneader is preferred. During melt-kneading, the cylinder set temperature of the kneading device is 20
The temperature is preferably in the range of 0 to 360 ° C, more preferably 23
0-350 ° C.

At the time of kneading, the respective components may be previously mixed uniformly using a device such as a tumbler or a Henschel mixer, or if necessary, the mixing may be omitted, and each component may be separately supplied to the kneading device. Methods can also be used.

Next, a specific method of forming a film by inflation film formation of the above liquid crystal polyester will be described.

First, a liquid crystal polyester in a molten state is fed into an inflation molding die 2 from an extruder (not shown), and is extruded into a cylindrical shape from an annular slit of the inflation molding die 2. Then, air is blown into the cylindrical resin, that is, the bubble B, through an air introduction pipe (not shown) formed in the inflation molding die 2 to expand the bubble B. The bubble B is guided to the pair of take-off rolls 4a and 4b while being folded flat by the pair of guide members 6a and 6b.

At this time, the bubble B is moved by both guide members 6a,
Before contacting the air permeable sheet 8 of FIG. 6b, as shown in FIG. 3A, the bubble B expands while being maintained in a cylindrical shape. When the bubble B comes into contact with both air permeable sheets 8 and starts to slide on the surface of the air permeable sheet 8, the air permeable sheet 8 is pushed outward by the internal pressure due to the expansion of the bubble B. This is combined with the wind pressure of the air blown from the air blower 10 toward the air permeable sheet 8, so that the air permeable sheet 8 smoothly wraps the bubble B as shown in FIG. Then, in this state, the bubble B is gradually folded flat. At this time, a pair of guide members 6
Since natural air and air blown from the air blower 10 enter the air permeable sheet 8 from outside the a and 6b, the bubble B is gradually cooled while being folded.
Finally, as shown in FIG. 3C, the bubble B becomes almost flat in a solidified state.

Here, when the bubble B comes into contact with each air permeable sheet 8 and wrinkles are generated in the bubble B due to the resistance at that time, the bubble B is gradually cooled as described above. The resin has a longer plasticity by that much, so that the wrinkles of the bubble B are almost completely removed before the bubble B is solidified at the upper part of each permeable sheet 8.

Thereafter, the flattened bubble B (cylindrical film) is taken up by a pair of take-up rolls 4a and 4b, and further taken up by a winder 5.

As described above, in the present embodiment, the portion of the pair of guide members 6a and 6b where the bubble B comes into contact is formed of the air permeable sheet 8, so that the bubble B The bubble B can be folded flat while cooling the bubble B without directly blowing air or the like on the bubble B. Thereby, wrinkles and thickness unevenness generated in the formed film are reduced.

Further, since air is blown to each air permeable sheet 8 by the air blower 10, the air permeable sheet 8 can wrap the bubble B smoothly, and the bubble B can be cooled efficiently. Also,
Since the air blower 10 is provided and the cooling water can be supplied to the first frame 7 which is a metal pipe, the bubble B can be sufficiently cooled even when a relatively thick film is formed. it can.

Although the preferred embodiments of the present invention have been described above, it goes without saying that the present invention is not limited to the above embodiments. For example, in the above-described embodiment, the air blower 10 is provided, and the first frame 7 is formed of a water-cooled metal pipe. However, when a relatively thin film is formed, the first frame 7 is formed from outside the pair of guide members 6a and 6b. The bubble B may be wrapped in both air permeable sheets 8 using only natural air that enters the air permeable sheets 8 appropriately.

Further, the resin guide device 3 of the above embodiment
Is positioned above the inflation molding die 2, but the present invention provides a resin guide in which a pair of guide members 6a and 6b are disposed below the inflation molding die 2 so as to taper downward. It is also applicable to devices.

In the above embodiment, a liquid crystal polymer which exhibits optical anisotropy when melted is used as the resin. However, general-purpose plastics such as polyethylene and polypropylene may be used.

[0082]

EXAMPLES The present invention will be described below with reference to examples, but these are merely examples, and the present invention is not limited to these examples. (1) Liquid crystalline polyester of component (A) p-acetoxybenzoic acid (8.3 kg, 60 mol), terephthalic acid, 2.49 kg (15 mol), isophthalic acid, 0.
83 kg (5 mol) and 5.45 kg (20.2 mol) of 4,4′-diacetoxydiphenyl were charged into a polymerization tank having a comb-shaped stirring blade, and the temperature was increased while stirring under a nitrogen gas atmosphere. For 1 hour. During this time, polymerization was carried out under strong stirring while liquefying and collecting and removing acetic acid gas produced as a by-product in a cooling tube. Thereafter, the system is gradually cooled,
The polymer obtained at 00 ° C. was taken out of the system. The obtained polymer was pulverized with a hammer mill manufactured by Hosokawa Micron Co., Ltd. to obtain particles of 2.5 mm or less. This was further treated at 280 ° C. for 3 hours in a nitrogen gas atmosphere in a rotary kiln to obtain a particulate wholly aromatic polyester having a flow start temperature of 324 ° C.

Here, the flow start temperature is defined as 4 ° C./cm using a Shimadzu Flow Tester Model CFT-500 manufactured by Shimadzu Corporation.
Resin heated and melted at a heating rate of
It is a temperature at which the melt viscosity shows 48,000 poise when extruded from a nozzle having an inner diameter of 1 mm and a length of 10 mm under f / cm ² .

Hereinafter, this liquid crystal polyester is abbreviated as A-1. This polymer showed optical anisotropy at 340 ° C. or higher under pressure. The repeating structural units of the liquid crystal polyester A-1 are as follows.

[0085]

Embedded image

(2) Rubber of Component (B) According to the method described in Example 5 of JP-A-61-127709, methyl acrylate / ethylene / glycidyl methacrylate = 59.0 / 38.7 / 2. .3 (weight ratio), a rubber having a Mooney viscosity of 15 was obtained. Here, the Mooney viscosity is a value measured using a large rotor at 100 ° C. according to JIS K6300. Hereinafter, this rubber is abbreviated as B-1.

(3) Measurement of air permeability 0.2 kg of a circular test piece having a diameter of 38 mm
/ Cm ² of air was applied, and how many cc of air passed per second was measured. This air permeability test is AST
Perm-Poromete compliant with MF316
r.

(4) Reference Example A-1 / B-1 = 85 parts by weight / 15 parts by weight.
Using TEX-30 twin screw extruder manufactured by Nippon Steel Corporation, cylinder set temperature 335 ° C, screw rotation speed 250r
The composition was obtained by melt-kneading at pm. The composition pellets exhibited optical anisotropy at 330 ° C. or higher under pressure. Hereinafter, this pellet may be abbreviated as P-1.

(5) Example A liquid crystal polymer (P-1) was sufficiently supplied to a resin supply port of a 60 mm Φ screw extruder, and the resin was discharged to an inflation molding die at a rotation speed of 120 rpm. The diameter of the die for inflation molding is 100 mm, and the gap of the lip (resin flow path) of the die is 1 mm. The extruder was set at an average temperature of 340 ° C., and the inflation molding die was set at 345 ° C. to form a film. The structure of the pair of guide members of the resin guide device is as follows. First, 10mm x 10m
One set (two) of 1 m × 1 m square frames made of a stainless steel bar having a cross section of m is prepared. Then, the square frame was arranged such that it became tapered with respect to the resin extrusion direction, and one side of the frame extended in parallel with the longitudinal direction of the take-up roll. At this time, the frame interval at the upper end (the end on the take-up roll side) of the pair of square frames is 70 mm, and the frame interval at the lower end (the end on the inflation molding die side) is 400 mm. On the inside (opposite side) of the pair of square frames, a glass woven cloth (Micro Glass Cloth YEM2 manufactured by Nippon Sheet Glass)
103) was pasted. The air permeability of this glass woven fabric is 13
00 / sec.

Then, the film flattened by such a pair of guide members was taken out under the conditions of a blow ratio of 3.0 and a drawdown ratio of 30.5. At this time, 300
Even when a 0 m roll was obtained, there was almost no change in the film, and the film could be stably formed. The width of the film obtained by folding flat and stacking two sheets was 470 mm, and the thickness of the film obtained by cutting and peeling both ends 50 mm was 11 ± 1 μm, and no wrinkles, looseness, etc. were recognized. .

(6) Comparative Example A 1 mm × 1 m aluminum plate having a thickness of 3 mm was attached to the square frame, and the glass woven cloth (micro glass cloth manufactured by Nippon Sheet Glass Co., Ltd.) was placed on the square frame.
1 formed by attaching YEM2103)
A pair of stabilizers was arranged in the same manner as in the above embodiment, and a film was formed under the same conditions as in the above embodiment. In this case, the expanded bubble swings left and right parallel to the surface of the stabilizer, and
In about 10 minutes, the cylindrical film was cut in a direction perpendicular to the direction in which the film was taken out, and stable film formation was not possible. The thickness of the film obtained by folding the sheet flat and peeling the two layers was 11 ± 4 μm, and many wrinkles and looseness were observed.

[0092]

According to the present invention, since the portion of the pair of guide members that comes into contact with the cylindrical resin is formed of a gas-permeable member, the cylindrical resin extruded from the inflation molding die can be used. The cylindrical resin can be folded flat while cooling it effectively without directly blowing air or the like. As a result, a film having a good appearance with less wrinkles and uneven thickness can be produced, and stable inflation molding can be performed.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing an inflation molding device including a resin guide device according to the present invention.

FIG. 2 is a perspective view of a resin guide device according to the present invention.

FIG. 3 is a view showing a state where bubbles are folded flat by a pair of guide members shown in FIGS. 1 and 2;

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Inflation molding device, 2 ... Inflation molding die, 3 ... Resin guide device, 4a, 4b ... Take-off roll, 6a, 6b ... Guide member, 7 ... 1st frame, 8
... air-permeable sheet (member having air permeability), 9 ... second frame, 10 ... air blower, B ... bubble (tubular resin).

Continued on the front page (72) Inventor Tomokazu Takayanagi 6th Kitahara, Tsukuba, Ibaraki Prefecture Sumitomo Chemical Co., Ltd. Noriyuki Oshima 2220 Fukutomi Shinmachi, Ashikaga City, Tochigi Prefecture F-term (reference) 4F207 AA24E AC07 AG01 AJ08 AJ10 AJ11 AK02 KA01 KA17 KA19 KK68 KW26

Claims (11)

[Claims] 1. A resin guide device in an inflation molding device, wherein a molten resin extruded into a cylindrical shape from an inflation molding die is guided to a pair of take-off rolls while being cooled, and the resin guide device is tapered toward the pair of take-off rolls. Are arranged so that
A resin guide device, comprising: a pair of guide members that fold the cylindrical resin flat, and a portion of each guide member that contacts the cylindrical resin is formed of a gas-permeable member. 2. The air-permeable member is made of an ASTM.
In an air permeability test using a Perm-Porometer based on F316, when the diameter of a circular test piece used for the test is 38 mm, the air pressure is set to 0.02 kg / cm.
^2. The resin guide device according to claim 1, wherein the air permeability when set to ² is 100 to 5000 cc / sec. 3. The resin guide device according to claim 1, further comprising a unit disposed outside each of the pair of guide members, for blowing a gas to the air-permeable member. 4. The guide member includes a first frame disposed adjacent to the take-up roll and extending substantially parallel to a longitudinal direction of the take-up roll, wherein the first frame includes the air permeable member. The resin guide device according to any one of claims 1 to 3, wherein a part of the member having the following is fixed. 5. The resin guide device according to claim 4, wherein a cooling passage is provided in the first frame. 6. The guide member includes a second frame disposed closer to the inflation molding die than the first frame, and the second frame includes another one of the members having air permeability. The resin guide device according to claim 4, wherein the portion is fixed so as to be wound up and unwound. 7. The air-permeable member is a mesh,
The resin guide device according to any one of claims 1 to 6, wherein the resin guide device is one of a woven fabric and a nonwoven fabric. 8. The resin according to claim 1, wherein the molten resin is extruded into a tubular shape from an inflation molding die, and a gas is blown into the tubular resin to expand the resin. A film is produced by flatly folding the expanded tubular resin by the pair of guide members of the guide device, taking up the flattened tubular resin, and further winding the film. Production method. 9. The method according to claim 8, wherein a liquid crystalline polymer exhibiting optical anisotropy when melted is used as the resin. 10. A liquid crystal polyester resin composition comprising (A) a liquid crystal polyester as a continuous phase and (B) a copolymer having a functional group reactive with the liquid crystal polyester as a dispersion phase. The method for producing a film according to claim 9, which is used. 11. A copolymer having (A) 56.0 to 99.9% by weight of a liquid crystal polyester and (B) a copolymer having a functional group reactive with the liquid crystal polyester as the liquid crystalline polymer. 10. The method for producing a film according to claim 9, wherein a composition obtained by melt-kneading 1% by weight is used.