JPS6325027A - Method and device for continuous manufacture of thin resin sheet - Google Patents

Abstract

PURPOSE:To permit the continuous manufacture of a thin resin sheet as well as the easy control of the thickness and the width of said resin sheet, by a method wherein molten resin is supplied to a box type resin dam and is sent out downwardly while cooling the resin in a space between rolls to form a solidified shell. CONSTITUTION:The pellet or powder of thermoplastic resin is supplied into a molten resin bath 2 to melt it and the molten resin is poured into a resin dam 5 arranged on cooling rills from the resin bath 2 through a nozzle 4. The molten resin on the cooling rolls 9 is extruded after regulating the thickness thereof between the rolls, since the rolls are rotated in reverse synchronizedly, then a solidified shell is formed after cooling the resin rapidly. The solidified shell is sent to a forming and reeling unit 12. The solidified shell is cooled further by cooling guide rolls 13 constituted of a plurality of pairs of rolls and is formed to a thin resin sheet 16 with a desired thickness. When the width of the thin sheet is to be changed, a side dam 6 is moved in parallel to the axis of the cooling roll 9.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a method and apparatus for continuously manufacturing thin resin sheets.

Conventional techniques and problems There are several methods for producing thin plates such as resin sheets and films.
Conventionally, the T-die method extrudes material through a linear slit,
There is a ring die method in which the material is extruded through a ring-shaped slit. The T-die method is mainly used to manufacture sheets, but the ring die method is used to manufacture rigid PVC corrugated sheets and foamed polystyrene sheets. There are many. Also,
Calendering methods are also known, in which sheets and films are produced by rolling resin with hot rolls.

Among the above-mentioned processing methods, the T-die method and ring die method:
It is well known that the thickness and width of the obtained thin resin plate cannot be easily changed, and in the calender method, although the thickness can be adjusted, the width of the resin thin plate cannot be adjusted.

In view of these circumstances, the present inventors have studied a method that allows continuous production of thin resin plates and easily controls the thickness and width of the thin resin plates, and have completed the present invention.

That is, the present invention is arranged on a pair of cooling rolls that rotate synchronously in opposite directions, and has a pair of wall surfaces that can move parallel to the axis of the rolls, and a pair of wall surfaces of a pond that are perpendicular to the wall surfaces. Continuous production of resin thin plates, in which molten resin is supplied to a box-shaped resin dam using a resin supply means, and the resin is sent downward while being cooled between the roll surfaces to form a solidified shell to continuously produce resin thin plates. A method and apparatus thereof are provided.

Hereinafter, the present invention will be explained in detail based on the accompanying drawings.

FIG. 1 is a schematic sectional view showing an example of an integrated structure of the apparatus of the present invention, and FIGS. 2 and 3 are detailed A7 views of the molten resin dam.

In FIG. 1, the apparatus of the present invention is comprised of a resin supply means (1), a molten resin dam (5), a cooling roll (9), and a forming and winding device (12). The resin supply means (I) is
It has a molten resin bath (2) for heating and melting the raw resin and a nozzle (4) for supplying the molten resin (3) from the resin bath to the molten resin dam (5). The resin dam (5) is placed on a pair of cooling rolls (9) below the resin supply means, and has a box shape with an open top and bottom. Next, a forming and winding device (12) is arranged behind the cooling roll (9),
This device includes a cooling guide roll (13) that guides a resin thin plate (16), and a pinch roll (1) that pinches and transfers the thin resin plate.
4) and a winder (15) that finally winds up the thin plate.

Here, the molten resin dam (5) is a cooling roll (9).
In order to pool the molten resin (3) between them and prevent it from leaking to the outside, it is arranged in contact with the upper surface of the cooling roll (9) and consists of a pair of wall surfaces that can move parallel to the axis of the roll. The side dam (6) and the parallel side dam (7) consisting of a pair of wall surfaces perpendicular to the side dam (6) form a box shape, and the lower end surface has a shape corresponding to the roll circumferential surface (second
and Figure 3). The side dam (6) can be easily driven in the plate width direction by a hydraulic cylinder (8), and the plate width of the thin resin plate (16) can be adjusted. In this specific example,
A space is provided between the molten resin bath (2) and the molten resin dam (5) by the ventilation seal (10), and an inert gas such as nitrogen is introduced into the space from the inert gas cylinder (11) to cool the molten resin (3). ) is prevented from being oxidized by air.

In order to produce a resin thin plate based on the method of the present invention using the above-mentioned apparatus, first, pellets or powder of thermoplastic resin such as polypropylene, polyethylene, polyamide, etc. are heated electrically.
After drying by high-frequency heating or the like, the resin is supplied alone or together with a filler to a molten resin bath (2) heated by electric heat, steam, etc., and dissolved. The viscosity of the molten resin (3) is preferably 500 to 20,000 poise.

The resin is then injected from the resin bath (2) through the nozzle (4) into a resin dam (5) placed on the cooling roll (9). Next, the molten resin on the cooling roll (9) is extruded with its thickness adjusted between the cooling rolls by synchronously rotating in opposite directions to form a solidified shell after rapid cooling. The solidified shell is then sent to a forming winder (12).

In the forming and winding device, the solidified shell is further cooled by a plurality of pairs of cooling guide rolls (13) installed directly below the cooling roll (9), and is turned into a thin resin plate (16) having a desired thickness. molded.

The sheet is further transferred to a winder (15) via a pinch roll (14) arranged at the rear of the line and driven in synchronism with the cooling roll, where it is wound up into a final product. next,
In order to change the width of the thin plate using the method of the present invention, the side dam (6) may be moved parallel to the axis of the cooling roll (9) using a hydraulic cylinder (8).

cold nose carp The present invention will be specifically explained below with reference to Examples.

Example 1 Using the apparatus shown in FIG. 1, a resin thin plate was manufactured under the manufacturing conditions shown in Table 1. The resin used was medium density polyethylene (M r = 6,5), and a resin thin plate with good transparency of 500 μm in thickness x 300 mm in width was obtained.Example 2 Except for using polypropylene resin (MI = 6.0) was manufactured under the same conditions as in Example 1, and had a thickness of 5 with good transparency.
A resin thin plate measuring 00 μm×width 300 mm was obtained.

Table 1 Effects of the Invention As described above, according to the present invention, the thickness of the resin plate can be reduced to approximately 1
It is possible to change the width within a wide range of 00 to 5000 μm, and the plate width can be easily changed, and various resin plates with good transparency can be manufactured in desired dimensions.

[Brief explanation of the drawing]

FIG. 1 is a schematic sectional view showing a specific example of the apparatus of the present invention, and FIGS. 2 and 3 are detailed views of a molten resin dam. The main symbols in the figure are as follows. ■... Resin supply means, 2... Molten resin bath, 4...
Nozzle, butt... Molten resin dam, 9... Cooling roll, 1
2... Molding winding device, 16... Resin thin plate. Patent applicant: Kobe Steel Oriyoshi Co., Ltd. Patent attorney: 2 people (including the above-mentioned person) Figure 1

Claims (2)

[Claims] (1) A box-shaped resin that is placed on a pair of cooling rolls that rotate synchronously in opposite directions and has a pair of wall surfaces that can move parallel to the axis of the rolls and another pair of wall surfaces that are perpendicular to the wall surfaces. A method for continuously producing a thin resin plate, in which a molten resin is supplied to a dam using a resin supply means, and the resin is sent downward while being cooled between the roll surfaces to form a solidified shell to continuously produce a thin resin plate. (2) Means for supplying molten resin; a pair of cooling rolls that rotate synchronously in opposite directions and send the supplied resin downward while cooling it; 1. An apparatus for continuously manufacturing thin resin sheets, comprising a box-shaped resin dam having a pair of wall surfaces movable parallel to an axis and another pair of wall surfaces perpendicular to the wall surfaces.