JPH053816B2 - - Google Patents

Description

[Detailed description of the invention]

(Industrial Application Field) The present invention relates to a method for manufacturing a resin thin film having a crosslinked structure. (Prior art) Conventionally, the method of producing thin films of crosslinked resins, especially rubber-like materials, has been to form sheets using calender roll sheet molding machines or extrusion sheet molding machines. , thin films, especially
It was difficult to create a film-like membrane with a thickness of less than 200μ. (Problems to be Solved by the Invention) In the case of the above conventional method, when the film thickness is reduced, it becomes difficult to peel it off from the forming roll, etc., and to prevent this, a release agent is applied or laminated with a support material. However, increasing the take-up speed makes it easier to cut, and as a result, it is difficult to make a thin film of 200 μm or less. Furthermore, as the film thickness becomes thinner, it becomes difficult to control the thickness, making it impossible to form a uniform thin film. (Means for Solving the Problems) The inventors of the present invention have conducted extensive research into these problems, and as a result, have come up with the following method. That is, one or more crosslinkable silicone resins, urethane resins, butadiene resins, isoprene resins, chloroprene resins, and fluorine resins are added to one or both sides of the base thermoplastic resin layer. Thermoplastic resin layers are laminated to form a sheet, and the laminated sheet is stretched 1.2 times or more in at least one direction, and then the crosslinkable thermoplastic resin layer is crosslinked and peeled.Also, the laminated sheet is simultaneously biaxially stretched. At least vertically and horizontally by stretching method
This is a method for producing a crosslinked resin thin film, which is characterized by stretching 1.2 times or more. The base thermoplastic resin described in the present invention is not particularly limited as long as it can be stretched, but a resin that can be stretched at a temperature lower than the crosslinkable temperature of the crosslinkable thermoplastic resin is preferred. For example, polyester resins such as polyethylene terephthalate, polyolefin resins such as polyethylene, fluororesins such as polyethylenetetrafluoroethylene and polyvinylidene fluoride, or polyvinyl alcohol resins are suitable. As for the crosslinkable thermoplastic resin, silicone resins, urethane resins, butadiene resins, isoprene resins, chloroprene resins, fluorine resins, and the like are preferred. Silicone resins have dimethylsiloxane units (CH ₃ ) ₂ SiO as their main component, and are often manufactured by heating ring-opening polymerization of cyclic dimethylsiloxane produced by hydrolyzing dimethyldichlorosilane with acid or alkali. The method is not limited to this method. Furthermore, silica, calcium carbonate, or titanium oxide may be added as a reinforcing agent or filler. As the crosslinking agent, benzoyl peroxide, bis-2,4-dichlorobenzoyl peroxide, dicumyl peroxide, etc. are used. Urethane resins are also made by reacting diisocyanates with polyesters or polyethers. Diisocyanates include 1,5 naphthylene diisocyanate, N,N'(4,4'dimethyl)3,
3' diphenyl diisocyanate, 4,4' diphenylmethane diisocyanate, etc. are applicable, but are not limited thereto. Furthermore, polyesters containing adipic acid and ethylene glycol, or adipic acid, diethylene glycol, and triol as main components are suitable, but are not particularly limited thereto. Further, butadiene-based resins include styrene-butadiene resin, acrylonitrile-butadiene resin, cis-butadiene resin, and the like. Styrene-butadiene resin is produced by a method in which styrene and butadiene are emulsified with soap and copolymerized using water as a dispersion medium, or by a method in which styrene and butadiene are solution-polymerized, but the method is not particularly limited to these methods. Acrylonitrile butadiene resin is copolymerized by emulsifying acrylonitrile and butadiene in a ratio of about 3:7 using water as a dispersion medium. These crosslinking agents are preferably sulfur, but are not particularly limited thereto. The fluororesin used in the present invention is a copolymer of vinylidene fluoride and propylene hexafluoride, or a copolymer of vinylidene fluoride and ethylene chloride trifluoride, but is not limited to these. . The crosslinking agent is preferably an aliphatic polyamine derivative, but is not particularly limited thereto. Methods for forming the resin film include a calendar roll method, an extrusion method, and a solution coating method, and any method may be used. Further, the stretching method is not particularly limited, but uniaxial stretching using two rolls and uniaxial or biaxial stretching using a tenter method are suitable. In particular, the simultaneous biaxial stretching method using the tenter method can hold only the edges of the laminated sheet and stretch it without damaging the center while holding it in the air.
Moreover, it is the best method because it allows you to increase the magnification both vertically and horizontally. The stretching ratio needs to be 1.2 times or more in at least one direction in order to increase the effect of thinning the film, and preferably 1.2 times or more in each direction. Furthermore, if the crosslinkable thermoplastic resin has adhesive properties, a method is adopted in which it is laminated only in the center of the base thermoplastic resin sheet. Further, the crosslinking method may be a method of heating the laminated sheet, or a method of irradiating the laminated sheet with radiation such as an electron beam, but is not particularly limited to these methods. The crosslinked resin thin film produced by the method of the present invention can be used for battery separates, gas or liquid separation membranes, clothing coatings, and the like. (Example) Hereinafter, it will be explained in detail using an example. Example 1 Dimethyl silicone, vapor-grown silica, and calcined diatomaceous earth silica were mixed, benzoyl peroxide was added as a crosslinking agent, a 200μ thick sheet was made by a calender roll method, and immediately a 120μ thick polyethylene terephthalate sheet was made. Laminated on stretched film. The laminated sheet was heated to 90% by tenter method.
After simultaneously biaxially stretching 3 times in length and width at 125°C and crosslinking by heating at 125°C, only the silicone thin film was peeled off. The silicone thin film had a thickness of 24μ and had good performance as shown in Table 1.

[Table] Example 2 Zinc oxide and ethylene thiorarea were added as a crosslinking agent to a chloroprene resin, and aldol-α-naphthylamine was further added as an anti-aging agent, and the mixture was kneaded using a kneading roll machine. Further, a sheet with a thickness of 200 μm was prepared using a calendar roll machine and immediately laminated with an unstretched polyethylene terephthalate film. The laminated sheet was heated to 90℃ using the tenter method.
The film was simultaneously biaxially stretched to double the length and width, and after crosslinking by heating at 150°C, only the chloroprene thin film was peeled off.
The chloroprene thin film had a thickness of 50μ and had good rubber elasticity. (Effects of the Invention) As described above, according to the method of the present invention, it is possible to easily produce a crosslinked resin thin film of 200 μm or less, which has been difficult to produce in the past.

Claims (1)

[Claims] 1. On one or both sides of the base thermoplastic resin layer,
Crosslinkable silicone resin, urethane resin,
One or more thermoplastic resin layers selected from butadiene resin, isoprene resin, chloroprene resin, and fluorine resin are laminated to form a sheet, and the laminated sheet is oriented in at least one direction.
A method for producing a crosslinked resin thin film, which comprises stretching a crosslinkable thermoplastic resin layer by 1.2 times or more, then crosslinking and peeling off the crosslinkable thermoplastic resin layer. 2. The method for producing a crosslinked resin thin film according to claim 1, characterized in that the laminated sheet is stretched by at least 1.2 times in both length and width by a simultaneous biaxial stretching method.