JP2002036334A - Method for manufacturing base film for application - Google Patents

Abstract

PROBLEM TO BE SOLVED: To industrially manufacture a base film for application to the skin which shows superb practical physical properties such as high pliability, stretchability, follow-up performance to the skin, dimensional stability to an efficacious component of plaster, suitability for perforation and cutting and the like. SOLUTION: A raw material for the base film for application composed of a styrene elastomer is extruded from a T-die 11 at 160-270 deg.C resin temperature and 15-30 MPa intracylinder resin pressure and the extrusions are cooled between an embossed chill roll 12 at 5-25 deg.C and a rubber roll 13 made of a silicone rubber with 50-80 rubber hardness in which aluminum oxide with 300-800 μm particle diameter is uniformly dispersed. Next, the extrusions are taken up by drive rolls 14-16 on condition that the surface velocity of the drive rolls 14-16 be 1.0-1.5 times that of the chill roll 12. A touch roll 17 is made of a foamed rubber with 20-30 rubber hardness and the base film for application composed of a styrene elastomer with 20-200 μm thickness is obtained by taking up the film F within the range of 0.05-0.2 MPa jamming pressure by the touch roll 17.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is used for film-like skin patches such as antiphlogistic analgesics and insect bites, and for plasters. The present invention relates to a method for producing a base film for application such as a film.

[0002]

2. Description of the Related Art Patches for medical hygiene are used for application to the skin by treating one or both sides of a substrate such as cloth or film with an adhesive. Above all, a patch using a film as a base material is widely used as an adhesive plaster, a poultice, and the like. As these substrate films, those containing soft polyvinyl chloride as a main component are widely used from the viewpoint of skin followability and texture during application.

[0003]

However, in recent years,
Due to the increasing interest in the global environment, the demand for materials that can be recycled, the need for materials that do not contain halogen elements, and the need for materials that are not suspected as brain irritants of plasticizers have been increasing. There is a demand to stop using vinyl. However, since polyolefin-based films are already widely manufactured, they can be manufactured sufficiently industrially, but sometimes have insufficient flexibility and elasticity, and may not satisfy the skin following ability. There is a problem in practical performance such as dimensional stability to medicinal ingredients such as salves, and improvement is required. On the other hand, in the case of a styrene-based elastomer film, although dimensional stability, flexibility and elasticity to medicinal ingredients such as salves are extremely excellent, it is difficult to produce industrially, and improvement of the production method is required. .

The present invention has been made in order to solve the above-mentioned problems of the prior art, and has excellent flexibility, stretchability, skin followability, dimensional stability to medicinal ingredients such as salves, and suitability for drilling. It is intended to industrially produce a base film for application having excellent practical properties such as cut suitability.

[0005]

In order to achieve the above object, the production method of the present invention comprises the steps of (a) resin temperature of 160 to 270 ° C.
After extruding from a T-die at a resin pressure of 15 to 30 MPa in a cylinder, (2) embossed chill roll at 5 to 25 ° C and (3) aluminum oxide with a particle size of 300 to 800 μm are uniformly dispersed. Cooling was performed between a rubber roll made of silicon rubber having a rubber hardness of 50 to 80, and (d) the surface speed of the drive roll was set to 1.
(E) The material of the touch roll is foam rubber with a rubber hardness of 20 to 30, and the pressing pressure of the touch roll is 0.05 to 0.2 MPa.
Characterized by winding in the range of (f) thickness 20 ~
Manufactures a base film for application consisting of a 200 μm styrene-based elastomer.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS First, a styrene-based elastomer used for a base film for application according to the present invention will be described.
The styrene-based elastomer used in the present invention refers to a block copolymer having two or more polymer blocks made of a vinyl aromatic compound in a molecule and one or more polymer blocks made of a conjugated diene compound. A hydrogenated block copolymer obtained by addition, or a blend obtained by melt-mixing this hydrogenated block copolymer with a paraffinic or naphthenic process oil and a polyolefin such as polyethylene or polypropylene. Say.

As the vinyl aromatic compound in the hydrogenated block copolymer, for example, styrene, α-methylstyrene,
o-, m- or p-methylstyrene, 1,3-dimethylstyrene, vinylnaphthalene, vinylanthracene and the like. Among them, styrene and α-methylstyrene are preferably used. A blend using a copolymer is called a styrene-based elastomer. In this composition, calcium carbonate, if necessary, as long as the gist of the present invention is not impaired,
Talc, titanium oxide, silica, clay, barium sulfate,
Fillers such as magnesium carbonate, glass fiber, and carbon fiber, and styrene resins such as polystyrene, polyalphamethylstyrene, high-impact polystyrene, and ABS;
Polyester resin such as polyethylene terephthalate, polybutylene terephthalate, nylon-6, nylon-6
6, Polyamide resin such as nylon-12, thermoplastic resin such as polyurethane resin, heat stabilizer, antioxidant, light stabilizer, flame retardant, tackifier, antistatic agent, foaming agent, coloring agent, etc. Addition is also possible.

Hereinafter, the manufacturing method of the present invention will be described. FIG. 1 shows a manufacturing apparatus used in the present invention. This manufacturing apparatus is generally called a T-die film forming apparatus.
It has an extruder 10 for extruding a styrene-based elastomer from a film die 11, which is generally called a T-die, and a take-up device, and is a widely used device. The method of the present invention requires the use of a T-die film forming apparatus.

The styrene elastomer E extruded from the T die 11 of the extruder 10 is
And is cooled to form a film F. At this time, the film F is rolled by the rubber roll 13 to the chill roll 1.
Pressed on 2. The film F is peeled off from the chill roll 12 by a doctor roll 14 disposed downstream of the chill roll 12 and the rubber roll 13. Downstream of the doctor roll 14, a processing roll 15 for adjusting film characteristics by corona discharge, a pinch roll 16 for removing stress of the film F, and a touch roll 17 for eliminating slack of the film F are arranged in this order. Are located. The doctor roll 14, the processing roll 15 and the pinch roll 16 are driving rolls for picking up the film F. The film F is wound on a winding shaft 19 by a winder 18 downstream of the touch roll 17. A number of guide rolls 20 indicated by white circles are arranged along the path of the film F.

First, in (a), the resin temperature of the styrene-based elastomer and the resin pressure in the cylinder of the extruder 10 for extruding the resin from the T-die 11 are as follows.
Resin temperature 160-270 ° C and resin pressure in cylinder 15-
Extruded from the T-die 11 at 30 MPa. If the resin temperature is lower than 160 ° C., the styrene elastomer may not be sufficiently plasticized, which may cause a problem.
C. is not preferable because black spot defects and the like due to carbides occur during long-term operation due to thermal decomposition. The preferred range of the resin temperature is from 180 to 250 ° C, more preferably from 200 to 250 ° C. Molding is performed at this resin temperature, and the resin pressure in the cylinder is increased to 15 to 30.
It is necessary to control to MPa. If the resin pressure is less than 15 MPa, unevenness of the film thickness, which is generally called surging or resonance, occurs, which is not preferable. On the other hand, if the resin pressure exceeds 30 MPa, resin leakage from the adapter part of the T-die film forming apparatus or the T-die 11 may occur, which may cause a problem in long-time operation, which is not preferable. By setting the resin temperature and the resin pressure in the cylinder within the range of the present invention, it is possible to obtain a uniform film without thickness unevenness.

Next, for cooling in (b), an embossed chill roll 12 of 5 to 25 ° C. was used.
It was found that the styrene-based elastomer was excellent in flexibility, but strong in adhesiveness and extremely poor in releasability from a chill roll. Initially, the inventors repeated studies on a mirror roll generally used, but could not improve the releasability from a chill roll. Then, when the chill roll 12 which was embossed with 180 mesh and had fine irregularities on the surface was used, the releasability was surprisingly improved.
Further, it has been found that when the temperature of the chill roll 12 is 5 to 25 ° C., the releasability is further improved and the production stability is improved. If the temperature of the chill roll 12 is less than 5 ° C., there is a problem that moisture in the air solidifies on the chill roll surface and adheres to the film surface. Also, the temperature of the chill roll 12 is
When the temperature exceeds 25 ° C., the cooling of the film F becomes insufficient, and the releasability may deteriorate, which is not preferable.

In (c), the chill roll 12 and the rubber roll 13 that sandwiches the film F are specified. As the rubber roll 13, a rubber roll made of silicon rubber having a rubber hardness of 50 to 80 in which aluminum oxide having a particle size of 300 to 800 μm is uniformly dispersed is used. By dispersing aluminum oxide having a particle size of 300 to 800 μm, fine irregularities were formed on the surface of the rubber roll, and the releasability from the film F was improved. If the rubber hardness is out of the range of 50 to 80, there is a problem in adhesion to the chill roll 12 and durability, which is not preferable. Also, the rubber roll 13 is 5 to 5 in the same manner as the chill roll 12 described above.
When the temperature is controlled in the range of 25 ° C., the production stability is further improved.
The rubber roll 12 may be formed by forming a rubber layer on the surface of a metal core, or may be formed entirely by rubber.

In (d), the control range of the drive rolls such as the doctor roll 14, the processing roll 15, and the pinch roll 16 until the film is wound is defined. The doctor roll 14, the processing roll 15, and the pinch roll 16 are each picked up in a range of 1.0 to 1.5 times the surface speed of the chill roll 12. The doctor roll 14 plays a role of peeling the film F from the chill roll 12, but if the ratio is less than 1.0, the peeling from the chill roll 12 will not be successful, and
In some cases, winding of the film F around 2 may occur, making it impossible to manufacture. Regarding the increase of this ratio, there is a case where there is not much problem with a film having poor flexibility and elasticity, such as general polyethylene, but the styrene, which is the main purpose of the present invention, has good flexibility and conformability to skin. If the ratio exceeds 1.5, the film will be stretched and wrinkles will occur in the winding line, making it impossible to produce a system elastomer.

Next, as for the processing roll 15 for performing the corona treatment, it is preferable to lower the tension of the film F after the film F is peeled off from the chill roll 12 by the doctor roll 14. It is preferable to set it lower. However, if the surface speed of the chill roll 12 is less than 1.0 times, large slack or lateral wrinkles may occur in the film F in the winding line, which is not preferable.

Finally, the purpose of the pinch roll 16 is to remove the stress applied to the film F. If the ratio between the surface speeds of the pinch roll 16 and the chill roll 12 is less than 1.0, wrinkles due to sagging may occur in the film F, and if the ratio exceeds 1.5 times, vertical wrinkles due to tension in the film F may occur. It is not preferable because it may occur. Controlling these three drive rolls 14, 15, and 16 until winding of the film F is a very important factor from the viewpoint of quality stability and production stability of the film obtained by the present invention.

(E) specifies a take-up method by winding. First, the material of the touch roll 17 is rubber hardness.
20-30 foam rubber. This makes it possible to control a delicate pressing pressure. The pressing pressure of the touch roll 17 is in the range of 0.05 to 0.2 MPa. If the pressing pressure is less than 0.05 MPa, there is a problem that the wound product film is shifted laterally during storage of the product film roll, which is not preferable. Also, if the pressing pressure exceeds 0.2 MPa, stress will remain on the wound product film,
Tightening occurs during storage of the product film roll, causing a fatal defect to the film.

Finally, (f) the thickness of the film F made of the styrene elastomer of the present invention is 20 to 200 μm. The thickness is preferably in the range of 20 to 200 μm from the viewpoint of the flexibility required for the base film for application for the purpose of the present invention and the ability to follow the skin.

Further, the present invention may further include a process such as a widening process. Further, dust generally generated as trimmings generated at the time of trimming of the film side portion can be recycled and pelletized and used in the raw material.

An adhesive material is prepared by treating one or both surfaces of the thus obtained base film with an adhesive, and the adhesive to be formed is the one used as a medical adhesive. If there is, it can be used without particular limitation. As the pressure-sensitive adhesive, an acrylic pressure-sensitive adhesive, a rubber-based pressure-sensitive adhesive or a silicone-based pressure-sensitive adhesive is preferably used. In addition, a drug or the like used for a plaster can be added to the adhesive. Furthermore, it is also possible to compound a cloth containing a drug like a commercially available plaster.
It is also possible to make small holes from the viewpoint of air permeability and the like.

The base film for a patch of the present invention obtained in this manner has excellent moldability and excellent skin-following properties. In addition to hygiene products, it is used in a wide range of applications, such as sports, leisure, nursing care, and fashion applications that take advantage of its excellent hygiene, flexibility, and elasticity.

[0021]

EXAMPLES Hereinafter, the present invention will be described specifically with reference to Examples, but the present invention is not limited to these Examples.

Examples 1 to 3 and Comparative Examples 1 to 3 Hydrogenated block copolymer (hydrogenated block copolymer manufactured by Kuraray, trade name: Septon 4033: number average molecular weight 100,000, styrene content 30%) and polyethylene resin 1 (Polyethylene manufactured by Nippon Unicar, trade name TUF-2070: linear low-density polyethylene), polyethylene resin-2 (polyethylene manufactured by Tosoh, trade name 6C01A: low-density polyethylene) and plasticizer (paraffin-based process oil manufactured by Idemitsu Kosan, product A styrene-based elastomer was prepared according to the formulation shown in Table 1 using a Diana Process PW-380) and a filler (Talc manufactured by Asada Flour Milling Co., Ltd., talc FFR). Using a twin-screw extruder (NR2-46 manufactured by Freesia Macross Co., Ltd.)
The mixture was melted and kneaded at a temperature of 0 ° C. and pelletized. The obtained pellets were subjected to T-die film formation (CBC Tech, film width 11) under the conditions shown in Table 2.
00 mm) to make each film 1000 m. As a chill roll, a mirror roll (mirror surface) and a 180 mesh emboss roll (emboss)
A rubber roll made of silicon rubber with a rubber hardness of 70 (addition) in which aluminum oxide with a particle size of 300 to 800 μm is evenly dispersed, and a silicon rubber with a rubber hardness of 70 with no aluminum oxide added Rubber roll (no addition) was used.

[0023]

[Table 1]

[0024]

[Table 2]

The film forming stability and the obtained films of Examples 1 to 3 and Comparative Examples 1 to 3 were evaluated.
The evaluation items are described below. Table 3 shows the results. Furthermore, in order to evaluate flexibility and stretchability, which are post-processing suitability and practical use suitability of the adhesive base material film of the present invention, comparison with commercial PVC films and polyethylene films was performed.

Film-forming stability Evaluation was made on the time required for collecting non-defective products, the resonance property, and the occurrence of wrinkles on the film. ◎ average polyethylene, ○
Is inferior to polyethylene, but good. (1) Mass production is labor-intensive.

Film Thickness Uniformity The film thickness of the collected sample was measured, and the thickness unevenness with respect to the average film thickness in the line direction was quantified and evaluated. ◎ Within ± 5%, ○
Within ± 10%, × ± 10% or more

Post-Processing Suitability A small hole having a diameter of 1 mm was drilled by a drilling machine (manufactured by Nakajima Kikai). The number of holes out of 100 was evaluated. ◎ 100
All of them, ○ 98 or more, △ 97 ~ 90, × 90 or less.

Evaluation of flexibility and stretchability After applying an acrylic pressure-sensitive adhesive to the obtained film,
Prepare a mm × 100 mm test piece, mount it on the elbows and knees where it is frequently bent and stretched in daily life,
Evaluation of skin followability, which is an index of flexibility and elasticity, was performed. ◎ Very good, ○ Good, △ Slightly stiff, × Hard and hard to bend.

[0030]

[Table 3]

As is apparent from Table 3, Examples 1 to 3 were used.
Indicates that a film having excellent film-forming stability and a uniform film thickness could be produced. Further, as compared with Reference Examples 1 and 2, the film was excellent in post-processing suitability and had excellent target flexibility. It can be seen that the material has elasticity and elasticity. In contrast, in Comparative Example 1, water condensed on the surface of the chill roll adheres to the film as water droplets, peeling from the chill roll does not work well, wrinkling occurs due to sagging of the film, and abnormal rise in resin pressure. Therefore, stable production of 1000m was impossible. In Comparative Example 2, the mirror roll was used for the chill roll, so that the film did not peel off from the chill roll, and was operated by increasing the surface speed ratio of the drive roll below the doctor roll in order to forcibly peel it off, but line management was difficult and wrinkles occurred. Therefore, stable production of 1000 m was impossible. In Comparative Example 3, the resin pressure in the cylinder was low, resonance occurred, and it was difficult to obtain a uniform film. In addition, since the temperature of the chill roll was high and aluminum oxide was not added to the rubber roll, the chill roll and the rubber roll were not used. The film had poor peelability, and the problem of film winding occurred. Further, a blocking problem was confirmed in the product film due to a high pressing pressure of the touch roll. These Comparative Examples 1 to 3 lacked film-forming stability.
Evaluation of the stretchability was performed, but the results were inferior to those of Examples 1 to 3 due to poor uniformity of the film thickness.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram illustrating an example of a manufacturing apparatus used in the present invention.

[Explanation of symbols]

10 ... Extrusion device, 11 ... T die, 12 ... Chill roll,
13: rubber roll, 14: doctor roll (drive roll), 15: processing roll (drive roll), 16: pinch roll (drive roll), 17: touch roll, 18: winding machine

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) B29L 7:00 A61L 15/06 (72) Inventor Takashi Murakami 4031-1 Omon Komon, Kurate-cho, Kurate-gun, Fukuoka Prefecture Oishi F term in industrial stock company (reference) 4C081 AA03 AA12 CA022 CA031 CA032 CA162 CA212 CA232 CB051 CC02 CE02 CE10 CF112 CF22 DA02 DC12 EA03 4F207 AA13 AG01 AR03 AR06 AR08 AR12 KA01 KA17 KK65 KL84 KM15 KM16 KM30

Claims (1)

[Claims] (1) After extruding from a T-die at a resin temperature of 160 to 270 ° C. and a resin pressure in a cylinder of 15 to 30 MPa,
(B) a chill roll with an embossed temperature of 5 to 25 ° C;
(C) Cooling is performed between a rubber roll made of silicon rubber and having a rubber hardness of 50 to 80 in which aluminum oxide having a particle size of 300 to 800 μm is uniformly dispersed. (D) Then, the surface speed of the drive roll is reduced by the chill roll. 1.0 to 1.5
Take over with the drive roll as the double range,
(E) The material of the touch roll is foamed rubber having a rubber hardness of 20 to 30, and the pressing pressure of the touch roll is wound in the range of 0.05 to 0.2 MPa. (F) The thickness is 20 to 200
A method for producing a base film for attachment comprising a μm styrene-based elastomer.