JPS5821581B2 - Tsuukiseibo Suifilm Oyobi Sonoseizohouhou - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a breathable waterproof film and a method for producing the same.

Its purpose is diaper covers, raincoats,
To provide a film that is breathable, does not swell, and is waterproof when used for rainy weather sportswear, snowwear, other agricultural coats, fishing coats, etc.

Synthetic resin films conventionally used for diaper covers and raincoats are waterproof, but have no breathability, and therefore tend to get stuffy and are extremely hot, making them unsuitable for rain, let alone sportswear for rainy weather. It could not be said to be sufficient as a coat or a diaper cover, and the emergence of a film that allows air and water vapor to pass through freely but does not allow water droplets to pass through has been awaited for a long time.

The inventor of the present invention has continued research for many years with this point in mind, and as a result, has discovered a film that is both breathable and waterproof, and a method for manufacturing the same.

That is, a film having a thermoplastic film 1 as a base, a thermosetting resin layer 2 provided on one side of the thermosetting resin layer 2, and a water repellent film 6 on the surface of the thermosetting resin layer 2, A large number of through holes 5 and the through holes 5 are formed throughout the film.
It is characterized by providing a substantially conical-shaped mountain with an apex of , and the apex of the mountain is on the side of the thermosetting resin layer 2, and the closer the apex is, the higher the degree of curing of the thermosetting resin is. The inventor has invented a breathable waterproof film, and the manufacturing method thereof includes a first step of applying a thermosetting resin to one side of a thermoplastic film and then pre-drying it, and a heating roll having a large number of needles. After the process has been completed, a large number of through holes are provided protruding from the side where the thermosetting resin is not applied, and the heat is applied so as to form a large number of approximately conical peaks with the through holes as the vertices. The inventors have now invented a method for producing a breathable waterproof film, which is characterized by comprising a second step of curing a curable resin and a third step of applying a water-repellent finish.

The present invention will be explained according to its manufacturing method.

The present invention utilizes a thermoplastic synthetic resin film as a substrate. For example, films of polyurethane, polyamide, polyvinyl chloride, polyolefin, etc. can be used, and the thickness thereof is usually preferably 20 to 70 microns, particularly for clothing. For practical use, 30 to 50 microns is suitable.

First, a thermosetting resin liquid is applied to one side of such a thermoplastic film.

As this coating method, a reverse roll coater, a knife over roll coater, a gravure coater, etc. can be used.

Examples of thermosetting resins include epoxy resins, two-component urethane resins, functional group-introduced acrylic resins, phenolic urea resins, and melamine resins, which may be used alone or in an appropriate combination. .

Usually, these thermosetting resins are used as a viscous solution dissolved in an organic solvent, but it goes without saying that an emulsion type resin may also be used.

It goes without saying that the solvent for the thermosetting resin must not dissolve or swell the base thermoplastic film, and special care must be taken when selecting the solvent for the base film and thermosetting resin. It takes.

In addition, the coating amount of thermosetting resin is 5 to 301 as solid content.
1/m2 is appropriate, and 8 to 15 g/m2 is particularly preferred.

In this way, the thermosetting resin is applied and then pre-dried at a temperature that does not harden the thermosetting resin, completing the first step of the present invention and leading to the next step.

Figure 1 shows a thermosetting resin 2 on one side of a thermoplastic film 1.
FIG. 2 is an enlarged cross-sectional view of the film after the first step of coating and preliminary drying has been completed.

Next, the second step will be explained.

FIG. 2 is a partially enlarged sectional view of the second step of the method of the present invention.
Using a heating roller/I/4 having a large number of needles 3, the film is inserted from the non-coated side of the thermosetting resin to open the through holes 5.
It shows how it is set up.

As shown in FIG. 2, the heating roll 4 has a needle 3 with a sharp tip.
The film 1 is provided with a large number of through holes 5, and the film around the through holes 5 forms an almost conical mountain with the through holes 5 as the apex, as shown in the figure, and the film is completely covered over the entire surface. This results in many mountains like this.

At this time, so that the entire film is supported by the tips of the needles 3 and does not float up, a brush roll, a roll wrapped with soft material such as felt, or a large number of protrusions that engage with the gaps between the many needles 3 are provided. In many cases, it is necessary to press down lightly with a roll or the like.

In this way, a large number of through holes are provided in the film, and at the same time, the heat of the ridges 3 is used to harden the thermosetting resin.

- The heating roll 4 on which a large number of needles 3 are provided is equipped with a heating device that can adjust the temperature, so that it can be set to any desired temperature and operated.

A roll having a large number of such needles can be manufactured by engraving or by welding the needles.

When a roll having such needles is heated from the inside, the heat radiation is greatest at the tips of the needles, so the thermoplastic film that comes into contact with the tips of the needles immediately becomes soft and becomes perforated.

Furthermore, the closer the thermosetting resin is to the tip of the needle, the more easily it is heated, so the hardening progresses the most around the through hole 5, and the further down the conical mountain it is, the less hardening occurs and the resin becomes softer. .

The most important feature of the present invention is that the needle 3 is inserted into the hole 5 to form the through hole 5, and the approximately conical peak formed there is hardened in that shape. When the needle 3 is removed, the peak does not turn inside out, and during use of the film of the present invention, since the film is harder near the top of the hole, the peak never turns inside out, and the overall texture of the film does not change. Even though it uses thermosetting resin, it is flexible.

It goes without saying that the temperature of the heating roll must be at a temperature at which the thermosetting resin used is cured, and at a temperature at which the thermoplastic film serving as the base is not melted.

The density of needles provided on the heating roll varies depending on the desired air permeability, but is usually 1 to 10 needles/cIn2.
4 pieces/Crn2 is preferable in terms of manufacturing.

Further, the appropriate size of the through hole is 0.1 to 9.5 mm in diameter.

As described above, the second step of fixing a large number of through holes in the film and the shape of a mountain with the through holes as the apex is completed, and then, in the third step, a water-repellent finish is applied.

Of course, this water-repellent finish may be applied to one side or both sides of the film.

However, if one side is water repellent, it is necessary to apply a water repellent finish to the side where the apex of the hole is located.

Examples of water-repellent finishing methods include the Parati-Fugu method and the spray method, but in the case of one-sided water repellency, the spray method is preferable.

As this water repellent, any water repellent that is normally used for clothing can be used, such as silicone-based, fluorine thread, pyridinium salt-based, ethylene urea-based, etc. Therefore, the lower the curing temperature, the more preferable it is.

FIG. 3 is an enlarged cross-sectional view of the film of the present invention, in which the water repellent film 6 is processed only on one side.

Although each step of the method of the present invention has been explained above, each of these steps may be performed discontinuously on Taniyahi alone, or may be processed continuously by connecting a series of devices. Of course.

The film of the present invention produced by the method of the present invention has many perforations, so it is breathable. It is difficult to get into the holes, and since it has been treated with a water-repellent treatment, water droplets spread out into a ball-like shape, and the surface at the tip of the holes is also treated with a water-repellent treatment, making it very difficult for water to get into it. Because of this, the force acting on the interface is very small, and the opposite phenomenon of capillary action works, so unless a very large water pressure is applied, water will never enter the pores.

Therefore, the film of the present invention also has good waterproof properties.

When the film of the present invention is used in raincoats, snowwear, sportswear for rainy weather, tents, agricultural coats, etc. that prevent water droplets from entering the exterior, the film can be used with the top side of the mountain facing outward. Because it is breathable, it is very cool and does not get stuffy, and it is also highly waterproof, almost completely preventing rain and other water.On the other hand, when used as a diaper cover to prevent water droplets from leaking inside. If you use the side with the apex of the hole on the inside, you can get an ideal diaper cover that won't get stuffy at all before urinating, and even after urinating, it won't leak outside due to its waterproof properties. be.

As mentioned above, since the film of the present invention has breathability and waterproofness, it can be used as clothing for leisure such as sports and travel, agriculture, fishing, etc., and as a diaper cover as mentioned above. It can also be used in many industrial applications.

Example 1 A polyurethane film with a thickness of 35 microns was prepared by adding tolylene diisocyanate to a toluene solution (solid content 35%) of polyester-based polyuntamp polymer in an amount of 7% based on the solid content of the polyurethane polymer. It was coated at a rate of 49 g/m20 using a reverse roll coater.

Then, it was dried with hot air at 90 to 100°C.

This material was treated with a heated roll in which 4 needles were planted per cfn2 as follows.

The length of this needle is 5 mm and the average thickness is 0.6 mm.
The tip is sharply pointed.

Adjust the temperature of the heat roll so that the humidity at the tip of the needle is 160°C, insert the ridges from the side where the two-component urethane is not applied, press lightly with a brush roll, and open the through holes. After that, the rotation of the hot roll was adjusted so that 1 minute and 30 seconds passed with the needle still inserted into the through hole.

Then, at the point where the film was removed from the ridges, a water repellent agent containing a 25-group emulsion of stearyl ethylene urea as a main component was sprayed, dried at a temperature of 80°C, and heat-treated at 130°C for 5 minutes.

The obtained film had many conical peaks, and the peaks had through holes of 0.2 to 0.4 rILrIL.

When this product was sewn into a raincoat using a welder and tested, it was found that normal rain did not get in at all, and its water pressure resistance was 250 mm.

In addition, since it was breathable, it did not get stuffy at all and was extremely comfortable to wear, and its texture was suitable for use as clothing.

Furthermore, since the film itself has an uneven shape, it does not stick to the skin, making it comfortable to wear, making it very suitable not only as a raincoat but also as sportswear for rainy days, snowwear, etc.

Example 2 A nylon film with a thickness of 30 microns was coated with epoxy resin (40%) toluene liquid to which a curing agent (diamine type) was added in a solid content ratio of 3 parts, using a gravure roll coater.
, 97 m2, dried at about 90°C, and then heated with a hot roll having the same needle as in Example 1 so that the tip of the needle was 140°C.
The temperature was adjusted to .degree. C., and the tube was inserted in the same manner as in Example 1.

The rotation of the roll was adjusted so that the needle remained inserted for 60 seconds.

Then, a water repellent emulsion containing stearamide methylpyridinium chloride as a main component was sprayed, pre-dried, and heat-treated at 130° C. for 8 minutes.

The resulting film had many peaks with holes at the top, had very good breathability, was highly waterproof, and did not allow any rain to leak through it.

Water pressure resistance was 300 mm.

Although this product has a slightly hard texture, it is excellent as a coat for agriculture and fishing, and it is possible to sew a coat that does not swell even on rainy days and is almost completely waterproof. Ta.

Example 3 A polyvinyl chloride film with a thickness of 40 microns was coated with butylated urea as a crosslinking agent by dissolving an active group-introduced acrylic copolymer in a methanol/acetono mixed solution at a solid content of 15%. The additive was applied to 80 g/m2 using a knife over roll coater, dried at 80°C, and then adjusted using a hot roll with the same needle as in Example 1 so that the humidity at the needle tip was 120°C. Then, it was inserted in the same manner as in Example 1.

The rotation of the roll was adjusted so that this thrusting state was maintained for 5 minutes.

Then, when the film was separated from the needle, a silicone water repellent was sprayed on it, dried, and heat treated at 110° C. for 15 minutes.

The resulting film has small peaks all over its surface, with 0.1-0.3m perforations at the top of the peaks, and has extremely good breathability and high waterproofness, with a water pressure resistance of up to 500mm. When used as a diaper cover, it was comfortable because it did not get stuffy, and even when urinating, it did not leak at all, making it extremely desirable.

[Brief explanation of drawings]

FIG. 1 is an enlarged view of a film that has undergone the first step of the method of the invention. FIG. 2 is an enlarged partial cross-sectional view of the second step of the method of the present invention. FIG. 3 is an enlarged cross-sectional view of the film of the present invention produced by the method of the present invention. 1 is a thermoplastic film, 2 is a thermosetting resin layer, 3 is a needle,
4 is a heating roll, 5 is a through hole, and 6 is a water repellent film.

Claims (1)

[Scope of Claims] 1 A film having a thermoplastic film 1 as a base, a thermosetting resin layer 2 provided on one side of the thermoplastic film 10, and a water repellent film 6 on the surface of the thermosetting resin layer 20. The entire film is provided with a large number of through holes 5 and a substantially conical mountain with the through holes 5 as the apex, and the apex of the mountain is on the thermosetting resin layer 2 side, and the apex is close to the apex. A breathable waterproof film characterized in that the thermosetting resin has a higher degree of curing. 2 Apply thermosetting resin to one side of the thermoplastic film,
Then, a first step of pre-drying, and a heating roll having a large number of needles to provide a large number of through holes protruding from the side where the thermosetting resin is not coated of the film that has completed the first step, It is characterized by comprising a second step of curing the thermosetting resin so as to form a large number of substantially conical peaks with the through holes as apexes, and a third step of applying a water repellent finish. Method for manufacturing breathable waterproof film.