JP2751049B2 - Resin film - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resin film formed by using gelatin powder ground in a solvent.

[0002]

2. Description of the Related Art Gelatin is a kind of derived protein which is insoluble in organic solvents, swells in cold water, dissolves in warm water to form a highly viscous sol, and has a concentration of 2-3% or more at room temperature. It is used as a modifier for synthetic rubber because of its characteristic of forming an elastic gel.

In addition, it has been attempted to mix a resin film with a resin film in order to produce a film having good stretchability by utilizing the same characteristics and to produce a film having a moisture absorbing / releasing function and having good water and air resistance. ing.

[0004] As a result of many experiments, it has been clarified that the finer the particle size of the gelatin contained in these synthetic rubbers or resin films, the more specific effects are exerted on the synthetic rubbers or resin films. ing.

In particular, in order to provide a resin film with elasticity, moisture absorption / release properties and water repellency by thinning the resin film, the particle size of gelatin powder contained in the resin film must be reduced. It was necessary to align in the range.

Therefore, gelatin that has been powdered or granulated has been pulverized with a dry ball mill or the like, and classified before use.

[0007]

However, in such a conventional method, it is difficult to re-pulverize gelatin, and it is necessary to produce a ground gelatin powder having uniform quality and uniform fine particle size. Could not.

[0008] Further, a resin film produced by using a ground gelatin powder in which such a characteristic characteristic of gelatin is impaired or a gelatin powder having a relatively large particle diameter is mixed is peculiar to the smoothness and touch. However, these films had a drawback that these films did not have a specific moisture absorbing / releasing function, a stretching function, a water repellent function, and the like due to gelatin mixed therein.

In particular, in the pulverization by a dry ball mill, which is a conventional method, a large amount of heat is generated during the pulverization due to grinding, impact or shearing, and various inconveniences are caused by the generated heat.

First, the heat generated during the pulverization sometimes causes the gelatin during the pulverization to be partially converted into a viscoelastic gel state, and it often occurs that the pulverized gelatin cannot be efficiently pulverized. Alternatively, there is a disadvantage that the gelatin particles are fused to each other to form a viscoelastic mass. In particular, such inconveniences occurred remarkably, for example, when the water content of the gelatin to be pulverized was high, or when the gelatin was pulverized under humid conditions.

[0011] Next, when water is rapidly lost from the gelatin during the grinding due to the heat generated during the grinding, the hydrophilicity of the ground gelatin powder is hindered, and there is a drawback that the function of swelling due to moisture or the function of eluting with warm water is lost. In particular, crushed gelatin powder based on crushing under the condition that the water content in the crushed gelatin is less than 2% by weight, inherent viscoelasticity such as hydrophilicity, adhesiveness or expansion and contraction inherent in gelatin powder. There is a disadvantage that various properties such as properties are impaired.

From this point, in order to pulverize powdered or granular gelatin with a dry ball mill, heat generated by friction or collision at the time of pulverization is accumulated as much as possible, or
It was necessary to pulverize slowly over a long period of time so as not to excessively generate such frictional heat. For this reason, the pulverization efficiency of gelatin is poor, and the particle size of the finished pulverized gelatin powder must be kept within a relatively large range, so that a finer gelatin powder cannot be obtained.

Therefore, powder or granular gelatin is mixed and mixed with a liquid polymer or a resin solution diluted with various solvents, and the powder or granular gelatin mixed with the liquid polymer or resin solution is charged into a wet pulverizer. And then crushed.

The wet pulverization method has the drawbacks that the flow resistance of the liquid polymer or resin solution is large, stirring and pulverization are not performed smoothly, and the mixed gelatin is not uniformly dispersed in the polymer. Was. In particular, when the stirring of this kind of liquid polymer or resin solution is continued, the viscosity of these polymer or resin solutions tends to increase with time, and it may be difficult to perform a smooth pulverization treatment by a wet pulverizer. In many cases, when the pulverization temperature in the pulverizer was increased with the stirring of the pulverizer, such inconvenience on pulverization tended to occur more remarkably.

When powder or granular gelatin is pulverized by a dry ball mill, a cooling or exhaust device for removing the heat generated due to the friction or impact, or a device for keeping the water content of gelatin constant, is used in the apparatus itself. It is necessary to provide a device or the like, which has a disadvantage that the crushing device itself becomes large-scale.

Further, when powder or granular gelatin is pulverized by a dry ball mill, the particle size of the gelatin powder produced by various conditions such as temperature, humidity or ball stirring speed in the pulverizer varies, and it takes a long time. There is a disadvantage that gelatin powder having a large particle size remains in gelatin powder having a fine particle size even by pulverization.

In particular, when powdered or granular gelatin is pulverized by a conventional method, the particle size is 1.0 μm (in the case of elongated particles, the particle size was measured on the shorter side; hereinafter referred to as μm).
From about 50 μm to produce a very fine particle size gelatin powder, but there is a disadvantage that a relatively large amount of relatively large particle size gelatin powder is left behind. In such a problem, grinding continues for a long time. The same was true when doing so.

As a result, when a sheet or film is formed by incorporating these gelatin powders into a resin material such as a polyurethane resin solution, a part of the mixed gelatin protrudes from the surface of the sheet or film, and this is the sheet or film. In addition to causing a rough feeling on the surface, the edge of the large gelatin particles is likely to be cut off from the periphery of the sheet or the film, and the gelatin particles having the large particle size fall out of the sheet or the film or from the portion. There was an inconvenience that cracks occurred on the surface of the sheet or film.

[0019] In particular, the inconvenience associated with the irregularity of the particle size of the gelatin powder in the above description is that the thickness of the film to be formed is reduced to 0.
This was noticeable when the thickness was extremely thin, such as from 02 to 0.006 mm.

In a method of pulverizing gelatin powder by a dry ball mill and a method of using the pulverized gelatin powder, granulated or powdered gelatin is pulverized at a water content of about 10 to 15% by weight, and the pulverized gelatin is pulverized. It is mixed with various resin materials in the same state. However, when such a gelatin powder is mixed with a resin material, the finer the gelatin powder to be mixed, the more the gelatin powder tends to be not smoothly dispersed in the resin material. In the case of a certain solution, for example, it has a disadvantage that it is not uniformly dispersed in these resin solutions.

In view of the disadvantages of the prior art, the present invention eliminates the adverse effect on the ground gelatin caused by the heat caused by the friction or impact generated when grinding the powder or granular gelatin powder,
In addition, it enables the pulverization and molding of fine gelatin powder having a uniform particle size, and the quality peculiar to gelatin is not impaired, and by preparing a gelatin powder having a uniform particle size in a solvent, It is possible to provide a resin film in which gelatin powder is uniformly mixed.

[0022]

According to the present invention, there is provided a resin film comprising, as a means for achieving the above object, gelatin powder belonging to a range finer than 6 μm, which has been wet-pulverized with a solvent as a medium. The milled gelatin powder was mixed with the resin material together with the solvent used as the wet medium used for the milling, and was mainly mixed with
It was configured as a plastic film having a thickness of 0.006 mm.

[0023]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a plastic film according to a typical embodiment of the present invention will be described.

Usually, solid gelatin prepared as tasteless, odorless white powder or transparent flakes (here, gelatin is mainly industrial gelatin, but may be gelatin of various properties and concentrations; Basically, wet pulverization using a wet ball mill with a solvent such as dimethylformamide and toluene under the condition of air-dry water content (water content when left in the air = equilibrium water content). Then, the gelatin is pulverized in a state where the gelatin is not in contact with and milled by the solvent. In the pulverization using a pulverizer such as a wet ball mill, the particle size of the pulverized gelatin powder is 6
The process is continued until the range becomes finer than μm.

In order to make the particle size of the gelatin powder pulverized by the wet pulverizer uniform and to pulverize the pulverized gelatin to a desired particle size in a short time, the gelatin powder supplied to the wet pulverizer is used. And the gelatin powder is 50
Fine gelatin powder belonging to a range smaller than μm is preferably classified by a sieve or an air classifier so as to be 90% by weight or more of the total amount of the gelatin powder.

The solvent used in the above description is typically an organic solvent, and a solvent suitable for a resin material such as a resin solution mixed with the ground gelatin is used. And this solvent requires that the gelatin be insoluble, typically dimethylformamide, toluene,
Methyl ethyl ketone and the like are used other methanol, isopropyl alcohol, n-butanol, benzyl alcohol, ethyl acetate, butyl acetate, acetone, methyl isobutyl ketone, cyclohexane, tetrahydrofuran,
Dioxane, xylol, 2-nitropropane, ethane dichloride, trichlorethylene, perchlorethylene, methyl cellosolve, ethyl cellosolve and the like are used.

Since gelatin is insoluble in such a solvent, gelatin does not swell or dissolve even when gelatin is mixed into the solvent, and water and the like in gelatin are absorbed by the solvent. The gelatin does not harden. Also, in the process of pulverizing gelatin, gelatin introduced into the solvent is pulverized in the same state as when mixed into the solvent.

Using such a solvent as a wet medium, granular or powdered gelatin is charged into a pulverizer to perform pulverization.

This pulverizing apparatus may be any apparatus as long as it is suitable for wet pulverization of powder or granules, and among various ball mills, one suitable for wet pulverization is mainly used.

The pulverization by the pulverizer is continued until the particle size of the input granules or powdered gelatin becomes smaller than 6 μm. Therefore, the grinding conditions such as the grinding time by the grinder are as follows: the capacity of the grinder, the diameter and the amount of the balls used in the grinder, the type and the amount of the gelatin to be charged into the grinder, and the usage. The type and amount of the solvent, the stirring speed of the crusher, and various conditions such as the crushing temperature can be changed as needed.However, grinding the gelatin as far as possible does not increase the solvent temperature during the crushing is the quality of the crushed gelatin. This is necessary so as not to cause the deterioration of.

Further, in order to more effectively perform the pulverization by the above-mentioned pulverizer, the pulverized gelatin is preliminarily pulverized, and the preliminarily pulverized gelatin is classified by the air volume classification based on the true specific gravity or the sieve classification based on the bulk to reduce the particle size. They are usually prepared by pulverization using a dry pulverizer such as a turbo mill.

As described above, in wet pulverization using a solvent in which gelatin is insoluble in a pulverizing medium, gelatin during pulverization does not dissolve, swell, or harden by the solvent, and the outside air It is characterized in that there is no moisture absorption and desorption phenomenon of gelatin during the pulverization since the pulverization is performed in a state where the pulverization is blocked. As a result, in the process of grinding the gelatin, the water content of the gelatin is not increased, and the gelatin does not fuse with each other or become soft and unsuitable for grinding or impact grinding. Further, the quality does not deteriorate until the water content of the gelatin is reduced in the process of grinding the gelatin and the hydrophilicity is impaired.
The gelatin powder pulverized in this manner is used together with a solvent at the time of pulverization for forming a plastic film.

Example 1 Gelatin was pulverized by a turbo mill in a state of an air-dried moisture content, and classified to obtain the following gelatin powder. The water content of this gelatin powder was 12% by weight, but in actual grinding of gelatin powder, it was possible to use gelatin powder having a water content in the range of 5 to 15% by weight. 29.85 μm or more to less than 42.21 μm 25.9% by weight 21.10〃 to 29.85〃 26.1〃14.92〃 to 21.10〃21.5〃10.55〃 to 14.92〃11 0.2〃7.46〃10.55〃6.3〃5.27〃7.46４６4.4〃3.73〃5.27〃1.4〃2.63〃3.77 １ 1.4 〃 1.69 〃 to 2.63 ０．８ 0.8 １．０ 1.01 〜 to 1.69 ０．６ 0.6 ０．６ 0.66 〜 to 1.01 〃 0.4 ０．４ 0.43 〜 to 0 .66 ０．０ 0.0 〃

The above gelatin powder was charged into a pulverizer at a ratio of 30 parts by weight to 100 parts by weight of dimethylformamide. 70% by volume of alumina-based balls having a diameter of 3 mm and 30% by volume of a solvent containing gelatin powder were used for this pulverizer.
% And stirred for 60 minutes to obtain a gelatin powder having the following particle size. 3.73 μm or more to less than 5.27 μm 11.0% by weight 2.63 mm to 3.73 mm 25.6 mm 1.69 mm to 2.63 mm 18.4 mm 1.01 mm to 1.69 mm 16 5.5 ０．６ 0.66 〃 1.01 〃 15.5 ０．４ 0.43 〃 0.66 ７ 7.5 ０．３ 0.34 〃 0.43 〃 5.2 ０．２ 0.24 〜 0.34 〃 0.3 〃

Example 2 The above-mentioned granulated powder or powdered gelatin in a turbo mill was crushed by a crusher filled with zirconia-based balls of 3 mm in diameter under the following conditions. The diameter became 6 μm or less. 50% (volume ratio) of a mixture of 50 parts by weight of gelatin mixed with 100 parts by weight of toluene 3% diameter zirconia ball 50% (by volume)

The amount of gelatin powder mixed with the solvent is appropriately determined depending on the properties of the solvent, particularly the degree of viscosity of the solvent, and dimethylformamide is higher in viscosity than toluene, so that the amount of gelatin powder is higher. It is necessary to make the blending amount smaller than that of toluene.

Further, when the amounts of gelatin and the solvent to be charged into the pulverizer are increased, much pulverization time is required to obtain the above-mentioned gelatin powder having a particle size of 6 μm corresponding to the increase. In addition, when the diameter of the ball charged into the crusher was increased, the crushing time was shortened. However, there was a tendency for large-diameter gelatin powder to remain, and for a ball having a diameter larger than necessary. When used, gelatin powder having a uniform particle size could not be obtained.

Further, when the gelatin powder was pulverized with a wet ball mill using dimethylformamide without previously adjusting the particle diameter of the gelatin powder as in Example 1,
It was necessary to lengthen the pulverization time by about 30 minutes as compared with the use of gelatin powder having a uniform particle size. And even in this pulverization,
A fine and uniform gelatin powder smaller than μm could be produced.

The gelatin powder pulverized by the above-described method was determined to have the following characteristics during the pulverization process and the produced gelatin powder.

First, the granular or powdered gelatin charged into the pulverizer is taken up mainly in an organic solvent in which the gelatin is insoluble, and the gelatin is wrapped in the solvent. Since the gelatin is pulverized in a crushed state, the gelatin does not fuse with each other and does not fuse with the ball or the surface of the pulverizer. In particular, the heat generated by the grinding or impact of the ball is not dispersed and directly transmitted to the gelatin by the solvent, and there is no fear that the gelatin is deteriorated by the heat or the gelatin is fused.
In addition, since the gelatin is pulverized in a state covered with the solvent, in the pulverization process of the gelatin, the gelatin becomes wet and swells or becomes sol-like, or in the pulverization process due to the evaporation and heating of the water. No gelling phenomenon occurs. Therefore, gelatin mixed with the solvent,
The solvent contains the water content when mixed, and does not impair the swelling function specific to gelatin or the properties such as hydrophilicity and specific viscoelasticity. Also, it is possible to reliably and easily produce a fine gelatin powder having a uniform particle size without making it difficult to pulverize due to the dampness of gelatin and the increase in viscosity with heating during the pulverization process of gelatin. Can be.

Further, the gelatin powder obtained by pulverization is
In the case of the above-mentioned pulverization method, the particle size is 6
It is finer than μm,
It has a feature that it is not entangled, and is further uniformly dispersed in the solvent used for pulverization, and has a feature that gelatin powder is generally dispersed like a suspension.

Each of the gelatin powders in these solvents floats in the solvent in an independent state, and is isolated from the outside air. This facilitates the management of the pulverized gelatin powder, and the pulverized gelatin powder does not become wet, harden, or fuse with each other.

The gelatin powder thus crushed is
It is mixed with a resin for molding together with the solution used for grinding the gelatin powder. The method of this compounding and the amount of the compounding are appropriately determined according to the characteristics of the resin film to be molded.

The resin to which the solvent having the above-mentioned gelatin powder is blended is a resin suitable for forming a film to be produced, and is made into a solution by the solvent. That is, usually, the above-mentioned gelatin powder is pulverized using a solvent suitable for the resin material of the resin film to be formed.

Accordingly, various plastic films can be formed by selecting the solvent and the resin material used for the wet pulverization.

The resin to be mixed with the solvent containing the gelatin powder may be in the form of a paste, a powder or a liquid. It is a high solution or a low viscosity dilute solution.

Thus, a film is produced using the resin mixed with the solvent. As a method for producing this film, an appropriate method such as inflation molding is used,
After coating the surface of the release paper, there is a method in which the release paper is peeled off to form a film.

The film produced in this way is
Since the particle size of the gelatin powder contained in these materials belongs to a range finer than 6 μm, even if the film thickness is in the range of 0.02 to 0.002 mm, the surface of these films From which no mixed gelatin powder was projected or protruded, and the film was smooth and had a good touch.

Also, by eluting a part of the gelatin powder contained in the resin molded product of the film produced as described above, a large number of holes finer than several microns are formed on the surface of the film. be able to.

By providing pores finer than 2-3 μm on the surface of the film, air permeability is provided to these films. In particular, the air permeability provided to this film is about 0.0004 μm. It has the feature of allowing water vapor having a particle size of 2. For this reason, the film can be provided with water resistance and moisture permeability.

Accordingly, the surface of various kinds of fabrics, leather or wood products contains the above-mentioned gelatin powder in an amount of 0.02 to 0.00.
When the gelatin powder in the film is eluted by laminating a film having a thickness of 2 mm, water resistance and moisture permeability specific to these fabrics, leathers, wood products and the like are brought. By the way, the diameter of a normal raindrop is 2000μ.
m, even in fine rain, 100 μm,
It does not pass through fine holes provided in the film.
Also, raindrops adhering to these film surfaces do not infiltrate through the fine holes due to surface tension.

Example 3 A polyurethane resin film was prepared using the solvent containing the gelatin powder, and this film was transferred to the surface of a woven or knitted fabric.

Gelatin powder finer than 6 μm 10 parts by weight Toluene 70 parts by weight Polyurethane resin solids 30 parts by weight This resin solution was applied to the surface of release paper with a doctor knife coating method to a thickness of 0.008 mm. Was dried and peeled off from the release paper to form a 0.008 mm thick film. Further, the release paper was peeled off while adhering to the surface of the nonwoven fabric having a thickness of 1.5 mm without peeling the film, thereby forming a film skin layer on the surface of the nonwoven fabric. Then, this nonwoven fabric was immersed in warm water at 60 ° C. and washed with hot water for 15 minutes. As a result, gelatin powder contained in the film disappeared by 35% by weight of the total amount.

A film was prepared by increasing the amount of the above-mentioned gelatin powder in the range of 3 to 30 parts by weight in increments of 5 parts by weight. The obtained film had good gloss and sufficient waist strength, but had a sticky feeling at the time of bonding. On the other hand, the film surface containing 35 parts by weight of gelatin powder has a contact resistance specific to gelatin and has a good touch, but when a strong force is applied to the film surface, wrinkles are formed on the film surface, and In the case of a product laminated with a film, the underlying fabric surface was partially exposed in a state where the surface was distorted. Therefore, the optimal amount of the gelatin powder is 3 to 30 parts by weight. However, the amount of the gelatin powder can be further changed depending on the type of the resin for forming the film, the amount of the solvent used, the molding conditions, and the like.

The gelatin powder eluted by the above-mentioned hot water washing can be dissolved in a large amount in a short time as the temperature of the hot water is increased, but the film or the laminate film is damaged. Or the base fabric is damaged. From this, it is necessary to comprehensively consider the type of fabric to be laminated, the material characteristics and the material characteristics of the film itself, the amount of gelatin powder contained in the film, and the amount of gelatin powder eluted from the film. Then, the gelatin powder contained in the film is eluted. Incidentally, in the polyurethane resin film of the above embodiment, it is ideal to make the gelatin powder elute with hot water or hot water at 60 to 150 ° C.,
In warm water of 60 ° C. or less, the amount of gelatin powder contained was small and the time required was long.

Example 4 70 parts by weight of toluene 10 parts by weight of gelatin powder finer than 6 μm 30 parts by weight of polyvinyl chloride resin The flexibility of the PVC film produced in Example 4 is increased, and the elasticity is higher than that of a conventional PVC film. And a moisture absorption function was provided.

Example 5 Toluene 70 parts by weight Gelatin powder finer than 6 μm 10 parts by weight Acrylic resin 30 parts by weight The film produced at the compounding ratio of Example 5 has excellent weather resistance and good abrasion resistance. The film had a feature that it was not sticky at the time of contact, and the film surface had good gloss.

Example 6 Toluene 70 parts by weight Gelatin powder finer than 6 μm 10 parts by weight Polyvinyl chloride resin 15 parts by weight Acrylic resin 15 parts by weight The film produced at the compounding ratio of Example 6 is the same as that of Example 5
Although the abrasion resistance tended to be inferior to that of the film No. 1, the feel was good and the adhesiveness at the time of lamination was good.

Example 7 A mixed solution obtained by mixing a solvent containing 30 parts by weight of gelatin powder in 100 parts by weight of a urethane resin was coated on release paper, and dried to obtain a film having a thickness of 0.006 mm. Was transferred to a woven fabric substrate and laminated. The surface of the woven fabric thus produced had no stickiness and was excellent in feel.

Example 8 A one-pack type urethane resin containing gelatin powder (a mixed solution containing 30% by weight of non-volatile components using gelatin powder-containing methyl ethyl ketone as a solvent) was coated on a release paper with a comma roll and dried.
Further, on this coating layer, a two-pack type urethane resin containing gelatin powder (a mixed solution of 50% by weight of non-volatile content using methyl ethyl ketone containing gelatin powder as a solvent) is applied.
After drying, a laminated film was formed, and the laminated film was peeled off from the release paper and laminated and bonded to the surface of the nonwoven fabric. The surface of the non-woven fabric having the laminated film had no sticky feeling, and the same adhesive strength as that of the laminate adhesive containing no gelatin powder was obtained.

[0061]

The resin film according to the present invention uses gelatin powder which has been ground in a state where the gelatin powder is separated by a solvent. It doesn't fit.

Further, when grinding the gelatin powder, no heat is generated due to the grinding or impact grinding, so that there is no inconvenience of fusion of the gelatin powder or deterioration of the quality due to the heat change.

Further, since the gelatin powder is pulverized while being covered with the solvent, the gelatin powder does not dry or swell during the pulverization process. Thus, there is no inconvenience that the hydrophilicity is not hindered by the drying of the gelatin powder, and the gelatin powder becomes viscous with the swelling and the pulverization is hindered.

From these facts, it was possible to reliably and efficiently produce gelatin powder having a particle size smaller than 6 μm in a short time.

Further, since the finely ground gelatin is dispersed in a solvent in a suspension state, the compounding of the film with the molding resin is facilitated and facilitated. It has the feature that gelatin powder is uniformly dispersed.

Therefore, when a film is formed using a resin mixture containing a gelatin powder belonging to a range finer than 6 μm, the film is formed in a state where the gelatin powder is uniformly dispersed in the film. You. For this reason, the film has characteristics of absorbing and releasing moisture peculiar to gelatin, moderate contact resistance, and elasticity, and preventing static electricity from being charged.

Further, since the particle size of the gelatin powder contained in this film was finer than 6 μm, it was made possible to form this film thinly. In particular, a film having a thickness of 0.006 mm was prepared, and the gelatin powder mixed was not protruded or protruded from the surface of the formed film.

Further, since the gelatin powder is uniformly exposed on the surface of the film to be formed, moisture absorption is effectively provided on the surface of the film, and a good touch feeling is provided.

Further, when the mixed gelatin powder is eluted from the surface of the film to be formed, an infinite number of fine pores of several microns are formed on the surface of the film. It has a feature of providing a moisture absorption / release function, particularly a water / moisture permeable function.

When the surface of the film formed as described above is subjected to a sanding treatment, the moisture absorption function and the moisture-permeation resistance function of the gelatin powder contained in the film and the good touch feeling are further promoted. .

The film using the gelatin powder according to the present invention is used as a synthetic leather material for various furniture, a personal accessory such as a bag, an interior material of an automobile, etc., and has a characteristic that does not carry static electricity. It is used for various electronic devices and keyboards for these operators.

The film having gelatin powder described above can be produced or used by the same method or technique as the usual film forming method not containing gelatin powder. From this, the film using the ground gelatin powder according to the present invention can be used as a means such as surface makeup for all commodities in daily life.

Claims (1)

(57) [Claims] 1. A powdered or granular gelatin is pulverized by wet pulverization using a solvent such as dimethylformamide or toluene as a medium, and the pulverized gelatin powder has a particle size smaller than 6 microns. A resin film, wherein the ground gelatin powder contained in the solvent is a part of the composition of the formed resin film.