JPS6063117A - Preparation of water repellent film - Google Patents

Abstract

PURPOSE:To obtain the titled soft, porous film for rain coat and the like by a method wherein vinyl chloride resin powder being dispersed in water along with plasticizer, water repellent is applied to the base material with surface releasability to form a coating film and the film is heated, melted then cooled. CONSTITUTION:A hundred weight parts of vinyl chloride resin powder are dispersed in water along with 20-80 weight parts of plasticizer (such as dioctylphthalate etc.) and 0.1-10 weight parts of repellent (such as silicone emulsion etc.), then, this dispersion liquid is applied to a base having surface peeling properties (such as release paper etc.) to form a coating film. The base provided with this coating film is heated in a hot stove etc. water is volatiled, particle surface of polyvinyl chloride resin powder is melted, neighboring particle surfaces stick to one another, then, cooled to obtain the desired film.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing a water-repellent film. More specifically, the present invention relates to a method for producing a soft, breathable film based on a vinyl chloride resin.

Films made of soft vinyl chloride resin have four strengths, flexibility,
Due to its excellent adhesive processability and weather resistance, it is widely used for umbrellas, raincoats, hats, etc., either alone or in combination with fabrics.

However, for applications such as umbrellas and raincoats, the films used for these applications are required to have water repellency, which means that water does not leak, and vinyl chloride resin films do not have sufficient water repellency. Improvements are desired.

Conventionally, the method of imparting water repellency to a film made of vinyl chloride resin is to mix a water repellent such as paraffin or silicone oil with the base vinyl chloride resin along with a plasticizer and stabilizer, and then use a calendar molding method. , method 1 of forming a film by extrusion molding or the like, or a method of forming a film without adding a water repellent, then applying a water repellent such as a reactive silicone compound to the surface of the film and drying, etc.
Some of them have been put into practical use.

However, the former method of blending a water repellent into a base resin and forming a film not only fails to fully exhibit the water repellent effect, but also slows down the gelation of the base vinyl chloride resin composition. Moreover, when forming a film using the calendar molding method, - so-called plate-out occurs.
When forming into a film by extrusion molding, so-called eye discharge occurs, which significantly impairs the appearance of the film.

This has the disadvantage that it also impairs film productivity.

The latter film surface post-treatment method not only fails to impart a sufficient water repellent effect, but also has the disadvantage that it is difficult to maintain the water repellent effect for a long period of time.

Under such circumstances, the inventors of the present invention have conducted extensive studies with the aim of providing an industrially advantageous method for manufacturing a soft water-repellent film suitable for uses such as umbrellas and raincoats. This led to the completion of the invention.

Therefore, the gist of the present invention is to disperse vinyl chloride resin powder in water together with a plasticizer and a water repellent, and to form a coating film by applying this dispersion to a base material that has surface releasability. The method of producing a water-repellent film is characterized in that the coating film is then heated, melted, and then cooled.

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, Examples include halogenated vinylidene compounds, acrylonitrile, methacrylonitrile, ethylene, and propylene.

These monomers 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 either a suspension polymerization method or an emulsion polymerization method. The vinyl chloride resin is preferably a powder having an average particle size of 70 microns or less. If the average particle diameter is larger than 70 microns, it becomes difficult to properly control the strength of the final film, which is not preferred. If the average particle diameter is too small, it will be difficult to produce a water-repellent film, so it is preferably at least 1 micron, preferably at least 3 microns.

Considering the strength and texture of the final water-repellent film, we use seven types of vinyl chloride resins, one made by suspension polymerization, one made by emulsion polymerization, and one made by different manufacturing methods. Various combinations can be selected, such as using a combination of materials, combining materials with different average degrees of polymerization, or selecting homopolymers or copolymers.

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.

Plasticizers that can be used for this removal include dioctyl phthalate, dibenzyl phthalate, butylbenzyl phthalate, 1141111111111111111.
・, diindecyl phthalate, didodecyl phthalate,
Phthalate esters such as diindecyl phthalate; aliphatic dibasic acid esters such as dioctyl adipate, di-n-butyl adipate, and diptyl sebacate; glycol esters such as pentaerythritol ester and diethylene glycol dipenzoate; Fatty acid esters such as methyl acetyl ricinoleate; Phosphate esters such as tricresyl phosphate and triphenyl phosphate; Epoxidized oils such as epoxidized soybean oil and epoxidized linseed oil; Acetyl tributyl citrate and acetyl trioctyl citrate Citric acid esters such as tri-n-butyl pyromellitate, tri-n-butyl pyromellitate, polypropylene adipate, and various other plasticizers such as polyester plasticizers. . These plasticizers may be used alone or in combination of two or more.

The amount of plasticizer can be selected within the range of 1.2 parts by weight based on 100 parts by weight of vinyl chloride resin. If the amount of plasticizer is less than 20 parts by weight, a water-repellent film with excellent flexibility cannot be obtained. Conversely, if the amount of plasticizer is g
If more force is applied than 0 parts by weight, it becomes too soft, which is not preferable.

According to the present invention, the vinyl chloride resin is dispersed in water with a water repellent in addition to a plasticizer.

In the present invention, the water repellent refers to a substance that reduces the surface free energy of a soft vinyl chloride resin film and makes it easier to repel water. Specifically, saturated hydrocarbon compounds such as paraffin, stearic acid, pyridinium salt type cationic surfactants, methylol stearamide, octadecyl ethylene urea; silicone resins, silicone compounds such as methylhydropolysiloxane; polyfluoroalkyl acrylates Examples include fluorine-containing compounds such as esters.

The amount of water repellent to be mixed is preferably selected depending on the type of water repellent and the degree of water repellency of the desired film, and is in the range of o, i-70 parts by weight per 100 parts by weight of vinyl chloride resin. It is better to choose within. If the amount of the water repellent is less than 0.1 part by weight, water repellency will not be exhibited, which is undesirable;
If the amount exceeds 0 parts by weight, not only will the water repellency not be improved, but the printability of the final water repellent film will be affected.
Add water repellent when properties such as adhesive workability and strength deteriorate.
It is preferable to use the desired dispersion liquid.

In order to disperse the vinyl chloride resin powder and plasticizer in water, it is preferable to use a dispersant.

Dispersants that can be used include those commonly known as surfactants. For example, anionic surfactants such as fatty acid cloth, alkyl sulfate salts, alkyl sulfonate salts; 1M amine salts, secondary amine salts,
Cationic surfactants such as tertiary amine salts; amphoteric surfactants such as alkyl betaines; nonionic surfactants such as polyoxyethylene alkyl ethers and polyoxyethylene alkyl amines.

The amount of the above dispersant is 9. /~S,O may be used in a range of % by weight.

To disperse the vinyl chloride resin powder and plasticizer in water, these two components are added to water in which the dispersant is dissolved and mixed by stirring. At this time, the ratio of water and solid content (sum of vinyl chloride resin and plasticizer) is such that the concentration of solid content is in the range of 2θ to go% by weight of the dispersion (sum of water and solid content). It is better.

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. The concentration of the solids is particularly preferably within the range of tio to 60% by weight within the above range.

The dispersion is stirred and mixed in order to absorb the plasticizer into the vinyl chloride resin powder. The stirring mixer that can be used in this case may be a stirring mixer that has been conventionally used for the purpose of dispersing a liquid into a solid.

A vinyl chloride resin and a plasticizer are dispersed in water, and after the latter is absorbed into the former, a water repellent is added. At this time, there is no need to increase the amount of water. After adding the water repellent, the dispersion is stirred and mixed.

The mixer used for this stirring mixing may be the same as the stirring mixer above.

When preparing the dispersion, small amounts of resin stabilizers, ultraviolet absorbers, fillers, dyes, pigments, flame retardants, etc. can be added and mixed.

When preparing the above dispersion using a stirring mixer, the dispersion contains
Since air bubbles, gels, and lumps may be contained, it is preferable to remove these using a vacuum defoaming machine, a honomixer, a roll mill, a filter, or the like.

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

This substrate functions to support the coating film based on the dispersion. The base material is preferably composed of a thin metal plate, paper, or a thin heat-resistant resin plate. The surface of this base material on which the coating film is to be formed is coated with a release agent to provide full surface releasability so that the water-repellent film obtained after heating and melting the coating film can be easily peeled off. I'll keep it.

To form a coating film by applying the dispersion to a base material, various coating methods known per se such as spray coating, roll coating, clavier coating, reverse coating, dip coating, and knife coating can be used. It's fine.

The thickness of the coating film formed on the releasable surface of the base material is:
It is preferable to adjust the thickness of the breathable film obtained after the next heating and melting process is in the range of 0.0 to 0.71 njH. When the coating film is heated, water evaporates, so the thickness of the final water-repellent film is
Compared to the original coating film, it becomes thinner at a rate corresponding to the water contained in it. If the water-repellent film is too thin, it will not have sufficient strength and will be less practical. For this reason, the thickness is preferably in the range of 0.0/~0.7Wn, especially 0.0! r-ro,! It is preferable to set it in the range of rW+.

According to the present invention, the coating film formed by the above method is heated to volatilize the water in the coating film, and then the surfaces of the resin particles are melted to cause the particles to adhere to each other. If water in the coating film is rapidly volatilized and resin particles are attached to the surface, many small cracks often occur in the final water-repellent film. To prevent the formation of this small crack,
Before heating to melt the surface of the resin particles, pre-drying is carried out by heating within a temperature range of 0 to 10°C for 5 minutes or less to remove a considerable proportion of the moisture in the coating film.
It is best to let it evaporate.

The coating film can be prepared with or without the above pre-drying.
The resin particles are heated to almost completely volatilize the water, melting the surface of the resin particles, and attaching them to the resin particles. If the heating temperature is too low, it will take a long time to heat. Various types can be selected depending on the thickness etc. The heating temperature range for melting the surface of the resin particles is preferably /fO-coqoC.

According to the present invention, the water-repellent film obtained after performing the heating and melting operations as described above is cooled to around room temperature, and the water-repellent film is peeled from a base material having surface releasability, or Roll together with the material into a roll.

The water-repellent film obtained by the method of the present invention can be subjected to secondary processing such as cutting and adhesion in the same way as ordinary soft plastic films. The water-repellent film obtained by the method of the present invention can be used for umbrellas, raincoats, raincoats, etc., either alone or by bonding it with cloth.

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

(1) When using the method of the present invention, a flexible film with excellent water repellency can be easily produced.

(2) The water-repellent film obtained by the method of the present invention does not require any special treatment on the surface of the film, unlike conventional methods.
It is easy to print and can be processed into a wide variety of products.

(3) The water-repellent film obtained by the method of the present invention is
Since the water repellent agent is held in the form of small particles inside the film, and some of the small particles are exposed on the surface of the film, it has excellent water repellent effect and excellent sustainability of the water repellent effect.

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/ Polyvinyl chloride powder produced by emulsion polymerization method and dried by spray drying method (average degree of polymerization/, 1001 average particle size 1
A mixed solution A was prepared by mixing three components in a proportion of 0 micron) by weight of SO, 77% by weight of water, and 3% by weight of ammonium oleate.

On the other hand, 65% by weight of dioctyl phthalate and 3-! Mixed liquid B was prepared by mixing three components consisting of 3% by weight of ammonium oleate.

Mixed liquid A and mixed liquid B were mixed at a weight ratio of 3.3 to 1 to prepare mixed liquid C. The solid content of this mixed liquid C is 3. on the left. ! The number of parts by weight of the plasticizer added to 700 parts by weight of polyvinyl chloride was 170 parts by weight.

Polyfluoroalkyl ester emulsion (manufactured by Asahi Glass ■,
Asahi Guard AG-310, an active ingredient (Kokuchi), was added in parts by weight and stirred to form a dispersion. pvc io
The ratio of the water repellent agent (active ingredient) to o parts by weight is /, parts by weight.

Spread the dispersion prepared as above on commercially available release paper (
A coating film was formed on the surface of paper (paper whose surface has been coated with a release agent) by a knife coating method.

The release paper on which this coating film was formed was heated for 2 minutes in a hot air oven whose temperature was adjusted to 770C to volatilize water, melt the particle surfaces of the polyvinyl chloride powder, and adhere the adjacent particle surfaces to each other.

After the above heating and melting operations are completed, it is cooled to an average thickness of about 0.
/Wrm water repellent film was obtained.

The contact angle with water, water repellency, tensile strength, washing resistance, etc. of the obtained water-repellent film were measured according to the following methods. The results are shown in Table 1.

Contact angle: Ermagoniometer type contact angle measuring device G
-/ type, the contact angle of water at 23C was measured.

Water repellency: Measured according to JIS L-109λ spray method.

Tensile strength: Measured according to JIS K-A2B, Z.

Washing resistance: Film O8L-0; l/l
After washing in accordance with method 103, water repellency was measured in accordance with JIS L-10q, z spray method.

Example 2 A silicone emulsion (as a water repellent) was added to part by weight of the mixture C100 prepared by the method described in Example
East silicon fPtHf sHg2θO1 active ingredient ti
3 parts by weight of 0%) were added thereto and stirred to form a dispersion. The ratio of the water repellent (active ingredient) to 700 parts by weight of polyvinyl chloride was 3.7 parts by weight.

The dispersion prepared as above was applied to the surface of the same type of release paper used in Example/by a knife coating method,
A coating film was formed. Then, under the same conditions as in Example/, a thickness of about 0. /rnm water repellent film was obtained.

The obtained water-repellent film was evaluated for contact angle, water repellency, tensile strength, washing resistance, etc. using the methods described in Examples. The results are shown in Table 7.

Comparative example/Polyvinyl chloride (p=/1oo) 100N parts Dioctyl phthalate 3g p Epoxidized soybean oil 2 parts by weight Ba-Zn composite stabilizer K, S Other raw materials,
The resin additives were uniformly mixed by a tri-blend method, heated and melted on a calendar roll, and rolled to form a film having a thickness of o, irrrm.

The film obtained by the above method was mixed with polyfluoroalkyl ester emulsion (manufactured by Asahi Glass, Asahi Guard AG).
-37o) After being immersed in the 3-weight polyhydric solution, it was heated for 1 minute in a hot air oven whose temperature was adjusted to gOC to volatilize water, and then heated for 3 minutes in a hot air oven whose temperature was adjusted to /1l-OC.

Various properties of the obtained film were evaluated by the methods described in Examples. The results are shown in Table 1.

Comparative Example Copolyvinyl chloride (p=i10o) 10o Parts by weight Dioctyl phthalate 3g Epoxidized soybean oil Co Ba-Zn composite stabilizer Co, Ta Silicone oil (5H-aoo manufactured by Toshi Silicon Shisha) z Parts by weight The following raw materials and resin additives were uniformly mixed by a tri-blend method, heated and melted on a calendar roll, and rolled to form a film having a thickness of o and 1 trvn.

Various properties of the obtained film were evaluated by the method described in Example 1. The results are shown in Table 1.

Table 1 According to Table 1, the film obtained by the method of the present invention has a large initial contact angle, high water repellency, and excellent washing resistance. The corners are small,
It is clear that the water repellency is low and the washing resistance is also poor.

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

Claims (2)

[Claims] (1) PVC resin powder is dispersed in water together with a plasticizer and a water repellent, this dispersion is applied to a base material with surface releasability to form a coating film, and then this coating film is heated. A method for producing a water-repellent film, which comprises melting and then cooling. (2) Claim No. (1) is characterized in that the amount of plasticizer 20-I is 0 parts by weight and the water repellent is 0.1 to 10 parts by weight relative to 100 parts by weight of vinyl chloride resin powder. A method for producing a water-repellent film as described in .