JPS5968342A - Production of air-permeable film - Google Patents

Abstract

PURPOSE:To obtain an air-permeable film useful for clothing, packaging, sanitary, supplies, etc., by dispersing a suspension-polymerized vinyl chloride resin and a plasticizer in water, adding a thickening agent thereto, and applying the resulting dispersion onto a substrate having a surface release property to form a coating film. CONSTITUTION:A suspension-polymerized vinyl chloride resin having an average particle size of 10-50mu and a plasticizer are dispersed in water, and a thickening agent is added thereto to adjust the viscosity of the soln. to 1,000-50,000cP, thus forming a dispersion. This dispersion is applied onto a substrate having a surface release property to form a coating film. It is desirable to preheat this film at 40-100 deg.C before the film is molten by heating. Then the film is molten by heating pref. at 160-240 deg.C and cooled to obtain an air-permeable non-rigid film composed of a vinyl chloride resin base.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing a breathable film, and more particularly to a method for producing a soft and breathable film based on a vinyl chloride resin.

The technology for manufacturing microporous separators for food batteries, pseudo-leather, etc. using vinyl chloride resin as a base was developed in 1973.
-23g! IG Publication, Special Public Sho Guken-923 Otsu Publication, Special Public Sho TLS-SGB Publication, Special Public Sho Da S-AQG'
; rq publication, Special Publication Shoq Otsu-: lS2bg publication, Special Publication Shoq7-/Otsuqgti Publication)・1;, Special Publication Sho 11'7-
/I39'lk publication, special public Sho S no 3! The methods described in 'F03 Publication, Japanese Patent Publication No. 33-119g7, etc. have been proposed, and some of them have been put into practical use.

Among these already proposed methods, a method using a composition containing a large amount of plasticizer as a base vinyl chloride resin as a raw material (
Special public show 39-23g! ig issue, special public Akida O-! ;2
There is a method described in Publication No. 3b.

However, by the methods described in these publications, the thickness was reduced to 0.
It is difficult to produce an extremely thin and flexible film with a thickness of around 1 m.

Under such circumstances, the present inventors have developed a method for clothing, packaging,
Used for sanitary products, etc., thickness 0/jnm @
Later, as a result of intensive studies with the aim of providing an industrially advantageous method for manufacturing soft breathable films, 1.
This has led to the completion of the present invention.

The gist of the present invention is to disperse vinyl chloride-based ridge resin with an average particle size of lθ to so microns obtained by a suspension polymerization method in water together with a plasticizer, and add a thickener to reduce the viscosity of the liquid. 000~s o, o o o centihoise V
The method is characterized by forming a finely dispersed dispersion, applying this dispersion to a base material with surface releasability to form a coating film, heating and melting the coating film, and then cooling it. The present invention relates to a method of manufacturing a breathable film.

The present invention will be explained in detail below.

In the present invention, the vinyl chloride resin refers to polyvinyl chloride and a copolymer mainly composed of vinyl chloride. Monomers copolymerizable with vinyl chloride include vinyl esters, vinyl ethers, acrylic acid or methacrylic acid and their esters, maleic acid or fumaric acid and their esters, maleic anhydride, aromatic vinyl compounds, ...Hynylidene compound, acrylonitrile, methacrylic acid 1) /l/, ethylene, propylene, etc. can be used.

These Mono 1- may be partially crosslinked by adding a trace amount of a compound containing a polyfunctional group.

The above-mentioned vinyl chloride resin is produced by a suspension polymerization method, and has an average particle size of 10 to 50 microns. If the average particle diameter is less than 70 microns, it is difficult to produce a film that is permeable and has a thickness of about 0/2 mm. On the other hand, if the average particle diameter is larger than SO micron, it is difficult to adjust the strength and air permeability of the final film, and it is impossible to obtain a film with a balance of these two properties. . Vinyl chloride resin (
As long as the average particle size is within the above range, one type of particles with a fairly uniform average particle size may be used, or two or more types of particles with different average particle sizes may be used in combination.

The raw material vinyl chloride resin may be a single resin (homopolymer), a copolymerized 4Qj resin, or two or more types, depending on the air permeability, strength, feel, etc. of the resulting breathable film. It is also possible to use the resin of husks by combining it with silk.

According to the present invention, the vinyl chloride resin is dispersed in water together with a plasticizer, and the plasticizer is absorbed into the vinyl chloride resin powder.

Examples of plasticizers that can be used include phthalate esters such as dioctyl phthalate, dibenzyl phthalate, 7'f rubenzyl phthalate, dibenzyl phthalate, diisodecyl phthalate, 7 dodecyl phthalate, and diisodecyl phthalate; dioctyl adipate. , aliphatic dibasic acid esters such as di-n-butyl adipate and diptyl sebacate; glycol esters such as pentaerythritol ester and diethylene glycol dibenzoate; fatty acid esters such as methyl acetyl ricinoleate; tricresyl Phosphate esters such as phosphate and triphenyl phosphate; epoxy7ated soybean oil,
Evoquinated oils such as epoxidized linseed oil; citric acid esters such as acetyl tributyl/trade, acetyl trioctyl citrate, tri-n-butyl/trade; trialkyl trimellitate, tetra-n-octyl pyromellitate, polypropylene Various plasticizers such as Ambate and other polyester sealants can be used. These plasticizers (・, -f= may also be used in combination of two or more types.The amount of plasticizer is 4 vinyl chloride resins, 10 plasticizers,
It can be selected within the range of 20 to 70 parts by weight based on 0 parts by weight. If the plasticizer-magnetic content is less than 20 parts by weight,
It cannot be said that it is a breathable film with excellent flexibility. (Notice: If the amount of plasticizer exceeds 70 parts by weight,
It becomes too soft which is not desirable.

A dispersant is used to disperse the vinyl chloride resin powder and plasticizer in water.Those that can be used as dispersants include those commonly known as surfactants.For example, Anionic surfactants such as fatty acid soaps, alkyl sulfate salts, and alkyl sulfonates; cationic surfactants such as primary amine salts, secondary amine salts, and tertiary amine salts; such as alkyl betaines. Ampholytic surfactants; Nonionic surfactants such as polyoxy7-ethylene alkyl ether and polyoxyenalene algylamine are mentioned.

The above-mentioned dispersant may be used in an amount of 0.7 to 30% based on the division between the vinyl chloride resin and the plasticizer.

Disperse the vinyl chloride-based ali powder and plasticizer with water. The ratio of the solid content (the sum of the resin and the plasticizer) is preferably within the range of 2o-go weight % of the dispersion (the sum of the water and the solid content).

This is because if the solid content concentration is lower or higher than the above range, it becomes difficult to control the thickness of the final film. Among the above ranges, it is particularly preferable for the solid substance to be in the range of Llo to 0 by weight.

According to the present invention, a thickener is added to the dispersion to adjust the viscosity and consistency of the dispersion to within the range of /1000 to θ000 centivoice. or 100
If the particle size is smaller than 0.07, the solids in this dispersion will settle out and form a uniform coating film.%f1
．． Therefore, the final ((obtainable 1 courage, i'I finome thickness uniform) (mainly impossible. Conversely (C1 minute convex 7, if the viscosity of the liquid is greater than 30,000 centimeters, the coating It becomes difficult to form a film.

The individuality of the dispersion liquid is determined by the degree of solid content in the dispersion liquid, the average particle diameter of the chloride-based resin, the type and amount of the dispersant, the coating method used to coat the substrate, etc. You can choose within the above range.

In order to determine the viscosity of the above dispersion (thickeners used include sodium alginate, propylene glycol alkynate, carunium cellulose glycolate, sodium cellulose glycolate, sodium starch glycolate, starch Examples include sodium phosphate esters, methylcellulose, sodium polyacrylate, polyhinyl alcohol, and seratin, which are soluble in water and have the effect of adjusting the viscosity of aqueous solutions.

When using this thickener, it is necessary to adjust the viscosity of the dispersion liquid within the above-mentioned range.

The dispersion is stirred and mixed in order to absorb the plasticizer into the vinyl chloride resin powder. If the vinyl chloride-based sphere fat powder absorbs the entire amount of the blended plasticizer, cracks will occur on the surface of the breathable film that is finally obtained. Therefore, when stirring and mixing the dispersed R-da, the plasticizer t that should be absorbed into the vinyl chloride resin powder should be a part of the blended plasticizer, preferably about half, and the rest should be absorbed into the water without being absorbed. It would be better to keep it in a dispersed state. To do this, add the entire amount of plasticizer to water and change the stirring intensity, stirring time, etc. to adjust the amount absorbed into the vinyl chloride resin powder.First, add about half of the plasticizer and mix it. A good method is to absorb almost the entire amount of plasticizer added to the vinyl chloride resin powder, and then add the remaining approximately half of the plasticizer to water and disperse it.

The stirring method used to disperse the vinyl chloride resin and plasticizer in water may be a stirring method conventionally used for the purpose of dispersing solids in liquids.

Ikonai Zuroko and Katesaru.

When preparing the above-mentioned molecular iZ liquid in a four-boiler joint, the dispersion liquid (
? -i:l: It is preferable to remove some of the air bubbles, kelp, and lumps by using a vacuum deaerator, Hobart mixer, roll mill, filter, etc.

According to the present invention, the dispersion prepared by the above method is
Apply to a substrate with surface releasability.

This base material (well, it functions to support the coating film based on the dispersion liquid.The base material is preferably composed of a thin metal plate, paper, or a thin heat-resistant resin plate.The coating film of this base material is formed. A release agent is applied to the surface so that the breathable film obtained after heating and melting the coated film can be easily peeled off.

To form a coating film by applying a dispersion liquid to a base material, spray coating method, roll coating method, Claviaco 1-i, '
Various coating methods known per se such as the J bath coating method, the dip coating method, and the knife coating method may be used.

The thickness of the coating film formed on the releasable surface of the base material is:
The thickness of the breathable film obtained after the next heating and melting process is in the range of 005 to Q, , S-mm (τ
, it is better to adjust. When the coating film is heated, the moisture evaporates, so the thickness of the final breathable film is
It should thicken at a rate corresponding to the moisture contained in it compared to the original coating film. If the breathable film is too thin, it will not have sufficient strength, it will be soft, and it will be less practical, which is undesirable. On the other hand, if it is too thick, it will not be able to exhibit sufficient breathability. It is preferable to set it in the range of ˜θS plane, and preferably in the range of 0.003 to 0.25.

According to the present invention, the coating formed by the above method,
The water in the coating film is evaporated by heating, and then the surfaces of the resin particles are melted in a bath to cause the particles to adhere to each other. If the water in the coating film evaporates rapidly and the fat particles adhere to the surface, the resulting breathable film will often have many small main rows. Therefore, before heating enough to melt the surface of the resin, pre-drying is performed by heating within a temperature range of 90 to 100°C for 5 minutes to remove moisture in the coating film. It's best to volatilize a considerable amount of it (・.

The coating film is heated with or without performing the above-mentioned pre-drying to evaporate the water almost completely, melt the resin particle surface, and then apply the coating. If the heating temperature of the carcass is too low, the surfaces of the resin particles will not melt even if heated for a long time, making it impossible to obtain a breathable film with excellent strength, which is not preferable.

On the other hand, if the heating temperature at this time is too high, even if the heating time is short, the resin particles will completely melt and the particle shape will collapse, making it impossible to form vent holes, which is undesirable. .

Various selections can be made depending on the heating temperature, the glass transition point of the vinyl chloride resin, the average particle diameter, the number of parts of plasticizer added, the thickness of the breathable film to be finally obtained, the amount of ventilation, etc. The heating temperature range for resin particle surface melting is 7
The temperature may be in the range of 60 to 290°C.

When the present invention is carried out, the air-permeable film obtained after heating and melting is cooled to around room temperature, and the air-permeable film is peeled from the base material having surface releasability, as described above. Or roll it up together with this base material.

Note that water repellency can be imparted to one or both lumens of the breathable film during or after cooling the film.

The breathable film obtained by the method of the present invention can be subjected to secondary processing such as the same construction as conventional soft plastic films and adhesion. The breathable film obtained by the method of the present invention can be used alone or in combination with other materials such as paper or cloth for clothing, packaging, sanitary products, and wallpaper.

The method of the present invention has particularly remarkable effects as described below, and has extremely high industrial utility value.

(1) When the method of the present invention (・ζ) (・Ma, the thickness is θ0/
Q. Can extremely thin and flexible breathable films in the range of 5 nrm be easily produced?

(2) When using the method of the present invention, select the amount of ventilation of the breathable film, the average particle size of the resin powder, the amount of plasticizer, the thickness of the coating film, the temperature and time for heating and melting the coating film, etc. This makes it easy to change (().

(3) When using the method of the present invention, it is easy to color the resulting breathable film, and it is also easy to impart water repellency.

(4) Breathable film obtained by the method of the present invention (・
The resin particles constituting the film form voids between adjacent particles, and these voids communicate from one side of the film to the other side.

Therefore, when used together with cloth for purposes such as rain gear and onme covers, moisture easily permeates through and there is no chance of evaporation.

Hereinafter, the present invention will be explained in more detail based on Examples, but the present invention is not limited to the following examples unless it exceeds the gist thereof.

Example/ 50% by weight of dried polyvinyl chloride powder (average polymerization f5f-1000, average particle size 90 microns) produced by suspension polymerization method, 7% by weight of water, 3% by weight of sodium dodecylbenzenesulfonate (DBS) Mixture A was prepared by mixing the three components in proportions of %.

On the other hand, a mixture B was prepared by mixing three components consisting of 45% by weight of dioctyl phthalate, 3% by weight of water, and triple ammonium oleate.

The solid content of the combined solution C is 5 g/g.

5% of methylcellulose (manufactured by Shin-Etsu Chemical Co., Ltd., Metrose qO8-1i/500) based on mixture C/parts by weight
0.3 parts by weight of an aqueous solution was added and stirred to form a dispersion. The viscosity of the dispersion was λ, 100 senna (measured using a B-type viscometer at /2 rpm).

The slow rate of sedimentation of the polyvinyl chloride particles in this dispersion was determined by measuring the transmittance ((6) at 555 millimicrons of the supernatant after the dispersion was allowed to stand at room temperature for 1 hour). The higher the transmittance ((6), the faster the sedimentation rate of the particles.) The measurement results are shown in Table 1. The surface of the paper ((
The release agent was coated on the surface of paper (paper coated with a release agent) by a knife coating method to form a coating film.

The release paper on which this coating film had been formed was left in a hot air oven controlled at gθ°Cυ°C for 3 minutes to perform preliminary drying for coating 11. Next, the negative tooth pattern with this coated film removed was 770
After leaving it in a hot air oven adjusted to a temperature of 1 minute to completely volatilize the moisture, the surface of the SZ polyvinyl chloride particles was melted, and the surfaces of adjacent particles were adhered to each other.

After the above heating and melting operations are completed, the film is preserved and a breathable film with an average thickness of approximately 0.000000000000000
It's n. This breathable film is referred to as ``film/'' (・U・ For ``film/'', the average thickness of the film, thickness fluctuation, film ventilation amount, film ventilation fluctuation, etc.
ijl, 11 was determined according to the following method. The performance+1 results are shown in Table 1.

Average thickness of film: The thickness of a 300 rpm film was measured at 10 points in the width direction, and the measured values were averaged.

Thickness fluctuation...means the difference between the maximum value and minimum value of the thickness measurement results above.

Film connoisseur fi! . . . Measurements were taken at S locations in the width direction of a 300+ran width fill ventilation tract, and the measured values were averaged. Nitrogen gas at 0.3 ky,/crd,
- It was fed at a pressure and expressed as the amount of permeation per square centimeter for 7 minutes (cc/=fi/L:i).

Fluctuation in ventilation amount... The maximum value and minimum value of the ventilation intermittent measurement results above mean the difference.

Comparative Example/Example/(・In addition to not adding methyl cellulose to the mixture C, a dispersion was obtained according to the procedure described on the same side.The viscosity of this dispersion was / !iθ
It was centipoise. Furthermore, the slow rate of sedimentation of this dispersion was determined by applying pressure in the same manner as described on the same side. The results are shown in Table 1.

A breathable film was produced from this dispersion using the same operating procedure as described in Example 1. This ventilated tE film is called "film λ" (A).

Various properties of "Filmco" were evaluated in the same manner as "Film/" was evaluated. The results are shown in Table 1.

Example 1 Except that the polysalt 1-hibinyl in the example described in Example 1 was replaced with a dried polyvinyl chloride powder (average degree of polymerization 1000, average particle diameter 20 microns) produced by a shallow polymerization method. A dispersion liquid was prepared by a procedure similar to that described in the same column.

The viscosity of the obtained dispersion and the slow speed of sedimentation method (W) were measured in the same manner as in Example. The results are shown in Table 11-
0 A breathable film was produced from this dispersion using the same operating procedure as described in Example/. This breathable film is referred to as "film 3."

Various properties of "Film 3" were measured in the same manner as in the previous example. The results are shown in Table 1.

Comparative Example λ A dispersion was obtained in accordance with the procedure described in the same paragraph except that methyl cellulose was not added to the mixture C in the example described in the Example. The viscosity and slow settling rate of this dispersion were measured in the same manner as in the previous example. The results are shown in Table 11-
From this dispersion, a breathable film was produced using the same operating procedure as described in Example/((). This breathable film is referred to as "Filmda".

Various properties of "Filmda" were measured in the same manner as in the previous example. The results are shown in Table 1.

Example 3 Mixed liquid C/parts by weight prepared in the same manner as described above: Methylcellulose (manufactured by Shin-Etsu Chemical Co., Ltd.) Metrose 90 S H1l
-000) 6-% water bath solution was added to 1 part of 03 weight (
A dispersion was obtained in the same manner as described in the same example. The slowness of this dispersion was measured in the same way as in the previous example (([-). The results are shown in Table 1.

A breathable film was produced from this dispersion using the same operating procedure as described in Example/. This breathable film is called a "film da". Regarding "Film 3-", various properties were measured using a sickle as in the previous example. The results are shown in Table 7.

Mixture C prepared in the same manner as described in Example/Example/
A dispersion was obtained in the same manner as described in the same example, except that 0.3 parts by weight of a 5% water bath solution of methyl cellulose (manufactured by Shin-Etsu Chemical Co., Ltd., Metrose 908Hg000) was added to 0.03 parts by weight. The viscosity and sedimentation rate of this dispersion were measured in the same manner as in the previous example, and the results are shown in Table 1.

A breathable film was produced from this dispersion using the same operating procedure as described in Example/. This breathable film is called "Film Otsu".

Table 1 shows the results of measuring various properties of "Film Otsu" in the same manner as in the previous example.

Examples Mixture C prepared in the same manner as described in Example/
A dispersion liquid was obtained in the same manner as described in the same example, except that 7 parts by weight of s% water bath solution of Metrose 90SHgooo was added to / parts by weight.

The viscosity and slow settling rate of this dispersion were measured as in the previous example. The results are shown in Table 1.

A breathable film was produced from this dispersion using the same operating procedure as described in Example 1. This J+ temper film is called "Film 7" (・ugh).

Various properties of "Film 7" were measured in the same manner as in the previous example. The results are shown in Table 1.

Comparative Example 3 Polyvinyl chloride in the example described in Example 1 and 1/ was produced by the Yoshishu polymerization method and dried polyvinyl chloride powder (=1/degree of homopolymerization 1000, average particle size gθ microns) A dispersion was prepared using the same procedure as described in the same column. The viscosity and sedimentation rate of this dispersion were measured in the same manner as in the previous example. Shown in the table - Ding.

A breathable film was produced from this dispersion using the same operating procedure as described in Example/. This breathable film is called "film g".

Various properties of "Film g" l were measured in the same manner as in the previous example. The results are shown in Table 1.

Comparative Example 2 A dispersion was obtained according to the same procedure as described in Comparative Example 3, except that mether cellulose was not added. The viscosity and slow settling rate of this dispersion were measured in the same manner as in the previous example, and the results are shown in Table 1.

A breathable film was produced from this dispersion using the same operating procedure as described in Example/. This breathable film is called a "film?"

The viscosity of "Film 9" was measured in the same manner as in the previous example, and the results are shown in Table 1-0. From Table 1, the following becomes clear.

(1) If the average particle diameter of the polyvinyl chloride powder is too large, the particles will settle quickly in the dispersion, making it impossible to obtain a breathable film with a uniform thickness and air permeability (Comparative Example 3,
(See comparative example).

(2) Use polyvinyl chloride powder with an average particle size of 6"0 microns or less, and adjust the viscosity of the dispersion to i 000-
j! ; When adjusted within the range of 0.000, the sedimentation of particles in the dispersion becomes slow, resulting in a breathable film with excellent properties such as less variation in thickness and less variation in air permeability. can do.

Applicant Mitsubishi Monsanto Chemicals Co., Ltd. Agent Patent Attorney Yo Hase - (7 others)

Claims (2)

[Claims] (1) Obtained by suspension polymerization method, average particle size is 70
~50 micron vinyl chloride resin is dispersed in water with a plasticizer, and a thickener is added to reduce the viscosity of the liquid to z000~so.
, ooo centivoise is adjusted, this dispersion is applied to a base material having surface releasability to form a coating film, the coating film is then heated and melted, and then cooled. A method of producing a sex film. (2) Before heating and melting the coating film ((, qO to 10
A method for producing a breathable film according to claim 1, characterized in that preheating is performed within 3 minutes at a temperature range of 0°C.