JP3132856B2 - Thermoplastic resin sheet manufacturing equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention is suitable for use in producing a thermoplastic resin sheet in which two kinds of thermoplastic resins are extruded and one resin layer is embedded in another resin layer. The present invention relates to an apparatus for manufacturing a thermoplastic resin sheet, and more particularly to an apparatus for manufacturing a thermoplastic resin sheet capable of freely changing the width dimension of an embedded resin layer even during manufacturing.

[0002]

2. Description of the Related Art Windshield glass used for automobiles, airplanes and the like, and laminated glass used for windows of buildings and the like are made of polyvinyl butyral resin plasticized between two opposing glass plates. And an intermediate film composed of

In order to manufacture an interlayer film used for such a laminated glass, generally, a polyvinyl butyral resin which is heated and melted while being kneaded in a cylinder is fed to an extrusion mold, and the extrusion mold is generally used. There is known a method of obtaining a thin film-like intermediate film by extruding the same. Since the interlayer film thus obtained is colorless and transparent and transmits most of the light, it has been attempted to provide a band-shaped colored portion in a part of the width of the intermediate film in order to limit the transmission of the light beam. . For example, in the case of a thermoplastic resin sheet used for a windshield of an automobile, by providing a colored band having a concentration gradient in an upper region of the sheet, it is possible to reduce sunlight rays illuminating a driver through the windshield.

In providing such a colored band on a sheet, Japanese Patent Publication No. 43606/1994 discloses an apparatus for manufacturing a sheet in which a colored band having a predetermined width is enclosed in a resin layer formed of a thermoplastic resin. Proposed. This apparatus includes a manifold to which a transparent thermoplastic resin (hereinafter, referred to as a transparent resin) is supplied, and a colored thermoplastic resin (hereinafter, referred to as a colored resin) which is provided in the manifold and is fed into the manifold. A torpedo-type probe to be supplied, a slit-shaped die orifice as an extrusion sheet outlet, and a land provided between the manifold and the slit-shaped die orifice.The main flow of the transparent resin enters the manifold, and the land is formed. When the resin is pushed out from the slit-shaped die orifice, the colored resin pushed out from the slit of the torpedo-shaped probe is sealed in the mainstream.

[0005] By the way, it is desired to freely change the width of the colored band according to the kind of the product and the like. For example, Japanese Patent Publication No. 54-26590,
JP-A-57-14018 and JP-A-61-270133 provide an internal dikel and a distribution pipe in a manifold, adjust the flow rate and thickness of a mold outlet by moving the pipe, and configure a sheet and a sheet. Although methods for changing the width have been proposed, these methods cannot change the width of the colored band. To change the width of the intermediate layer, it is conceivable to replace it with a torpedo type probe with a different slit size. There is a drawback that the mold needs to be disassembled and cleaned, resulting in an increase in material loss.

Accordingly, the present inventors constructed a conduit disposed in the manifold so as to be movable in the width direction of the manifold, so that the conduit was embedded in the transparent resin layer even during the production of the sheet. An apparatus for manufacturing a thermoplastic resin sheet in which the width of the colored band is variable was studied. This device will be described with reference to FIGS.

The apparatus for manufacturing a thermoplastic resin sheet shown in FIGS. 4 and 5 has an extrusion molding die 31 and a conduit 32. The mold 31 includes a manifold 33 in which a conduit 32 is disposed, a side plate 45 provided in the width direction of the manifold 33, and a first thermoplastic resin (hereinafter, referred to as a first resin) melted in the manifold 33. The first to supply a)
It has a resin supply path 34, a slit-shaped die orifice 36 as an extrusion sheet outlet, and a land part 37 as a resin passage through which the first resin a is sent from the manifold 33 to the die orifice 36. The conduit 32 is disposed in the manifold 33 over its entire width, and is configured to be movable in the width direction of the manifold 33. The conduit 32 has a slit portion 4 opening into the manifold 33.
1 are formed, and the slit portion 41 is arranged at a position in the manifold 33 where the first resin a has a flow in the width direction. A second thermoplastic resin (hereinafter, referred to as a second resin) b is configured to be supplied into the conduit 33, and the second resin b is extruded into the manifold 33 through the slit portion 41.

FIGS. 4 and 5 show a state in which the first resin a is supplied into the manifold 33 and the second resin b is supplied into the conduit 32. FIG. The second resin b is the first resin
It moves in the direction indicated by arrow X in the figure due to the flow of resin a. As a result, as shown in FIG. 3, a thermoplastic resin sheet 19 in which the second resin layer B having a predetermined width is embedded in the first resin layer A is manufactured.

In order to reduce the width of the second resin layer B, as shown in FIG. 5, the conduit 32 is moved to the left in the figure by a predetermined distance, and one end of the slit portion 41 is shielded by the side plate 45. I do. As a result, the width of the slit portion 41 opening to the manifold 33 is reduced by being restricted by the side wall 46 of the side plate 45, so that the first resin a and the second resin b are separated from the inside of the manifold 33 and the conduit 3 in the same manner as described above.
2, the thermoplastic resin sheet 19 having a small width of the second resin layer B can be obtained.

However, when the thermoplastic resin sheet having the small width of the second resin layer B is manufactured by moving the conduit 32 as described above, the end portion of the slit portion 41 whose opening is shielded by the side plate 45 (see FIG. As a result, the second resin b discharged from the opening on the resin supply side from the side wall 46 flows out rightward in the drawing and converges on the side plate 45 side of the manifold 33.
Thickness deviation in the formed second resin layer B (part C in FIG. 5)
There was a problem that occurs.

[0011]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned drawbacks, and an object of the present invention is to provide a second resin layer embedded in a first resin layer even during continuous production. It is an object of the present invention to provide an apparatus for manufacturing a thermoplastic resin sheet which can freely change the width of the second resin layer and does not cause a thickness deviation of the formed second resin layer.

[0012]

An apparatus for manufacturing a thermoplastic resin sheet according to the present invention comprises a first resin layer formed of a first resin and a second resin layer embedded in the first resin layer. And a second resin layer having a predetermined width formed in the above, a thermoplastic resin sheet manufacturing apparatus, comprising an extrusion mold and a conduit, the extrusion mold, A manifold to which a first thermoplastic resin is supplied, and a slit-shaped die orifice in which the first thermoplastic resin is extruded outward from the manifold to form the first resin layer,
The conduit is disposed in the manifold and supported by a mold so as to be movable in the axial direction thereof. The conduit has a second resin supply passage through which a second thermoplastic resin is supplied, and a second resin supply passage in the manifold. A slit portion in which the resin supply path is opened, and a closing member capable of closing an end of the slit portion on the side wall portion side of the mold is provided in the mold, whereby the object is achieved. You.

[0013]

When the conduit is moved in the axial direction, the width of the opening of the slit portion closed by the closing member changes, so that the shape of the second resin layer formed of the second resin extruded through the slit portion is changed. Different thermoplastic resin sheets can be manufactured.

When the conduit is moved to reduce the opening width of the slit, an unnecessary opening at the end is closed by a closing member. There is no occurrence of a situation in which the plastic resin leaks out from the end of the slit portion and flows out, and no thickness deviation occurs on the resin supply path side of the formed second resin layer.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS.

FIGS. 1 and 2 show an example of an apparatus for producing a thermoplastic resin sheet according to the present invention.

The apparatus has an extrusion mold 1 and a conduit 2. The mold 1 includes a manifold 3 in which a conduit 2 is disposed, and a first resin supply path 12 for supplying a molten first resin a supplied from a resin extruder (not shown) into the manifold 3. It has a die adapter 20 provided, a slit-shaped die orifice 15 as an extrusion sheet outlet, and a land part 14 as a resin passage through which the first resin a is sent from the manifold 3 to the die orifice 15.

As shown in FIG. 2, the manifold 3 has a substantially circular cross section, and is provided over substantially the entire width of the mold 1.

The conduit 2 is made of a long tubular member.
A second resin supply passage 13 is provided therein, a resin inlet 21 communicating with an extruder (not shown) for the second resin b is provided at one end, and a blind plug 16 is provided at the other end. It is closed.

The conduit 2 is disposed in the manifold 3 over its entire width. The conduit 2 is inserted into the manifold 3 through a through hole of the sleeve 11 fixed to one side of the die adapter 20, and is connected to the die adapter 20 of the mold 1. The sleeve 17 extends outward through a through hole of the sleeve 17 fixed to the side opposite to the side. The inner surfaces of the sleeves 11 and 17 are provided with seal rings 10 and 4 slidably in contact with the outer peripheral surface of the conduit 2, respectively. A thread portion 6 is engraved on the extension end of the conduit 2 on the sleeve 17 side, and the moving nut 5 is screwed into the thread portion 6. The moving nut 5 is connected to the sleeve 17.
Is rotatably engaged with the flange 18 in the circumferential direction. A parallel key (not shown) is provided between the sleeve 17 and the conduit 2 to allow the conduit 2 to move in the axial direction and to restrict the rotation of the conduit 2. Therefore, by rotating the moving nut 5, the conduit 2 moves in the axial direction by screwing the nut 5 and the screw portion 6.

As shown in FIG. 2, a second resin supply passage 13 provided in the conduit 2 is opened in the manifold 3, and a slit 9 is formed in this opening.

The slit portion 9 is connected to the conduit 2 as described above.
One end is provided at a position where it is closed by the die adapter 20 (the side wall of the mold 1) when the is moved in the axial direction.

The die adapter 20 is provided with a closing piece 8 as a closing member for closing a portion of the slit portion 9 on the side wall portion side (left side in the figure) of the mold 1. This closing piece 8
Is formed of a curved piece and is rotatably engaged with the distal ends of the pressing screws 7, 7 penetrating the die adapter 20, and acts on the conduit 2 from the closing piece 8 by tightening the pressing screws 7. The pressing force can be adjusted. Therefore, the pressing force of the closing piece 8 can be adjusted from outside the mold 1.

The second resin b flows into the manifold 3 through the second resin supply passage 13 and the slit 9. In addition, the slit part 9 is a slit-shaped die orifice 1.
5 and is formed so as to face the land portion 14 side. Since the rotation of the conduit 2 is regulated by the parallel key as described above, the direction of the slit 9 is maintained in the above-described direction.

The width of the opening of the slit 8 can be changed by moving the conduit 2 in the axial direction as described below.

First, the pressing screws 7, 7 are loosened to such an extent that the conduit 2 becomes movable, so that the pressing force of the closing piece 8 is reduced.
Next, the conduit 2 is moved in the axial direction by rotating the moving nut 5. At this time, for example, if the conduit 2 is moved to the resin supply side (left side in the figure), the resin supply side end of the slit portion 9 is closed by the closing piece 8 to reduce the width of the opening. If 2 is located on the center side of the manifold 3, the width of the opening becomes the maximum width up to the width of the slit 9. After moving the conduit 2 and setting the opening width of the slit portion 9 to be a desired width, the pressing screws 7 are tightened to close unnecessary portions of the opening of the slit portion 9 with the closing pieces 8.

Next, a method for producing a thermoplastic resin sheet using the above-described apparatus of the present invention will be described.

The first resin a sent from the first resin supply path 12 into the manifold 3 fills the inside of the manifold 3, and is pushed out from the slit-shaped die orifice 15 through the land portion 14. On the other hand, the second resin supply path 13 of the conduit 2
The second resin b supplied to the inside is sent from the slit portion 9 of the conduit 2 into the manifold 3. Then, a second resin layer B having a predetermined width formed of the second resin b is embedded in the first resin layer A formed of the first resin a, and a thermoplastic resin as shown in FIG. The sheet 19 is formed. Here, since the width of the second resin layer B is affected by the width of the opening of the slit 9, the width of the second resin layer B is changed by changing the width of the opening of the slit 8 as described above. The dimensions can be arbitrarily changed to the desired width dimensions.

As described above, since the pressing screws 7 for fixing the closing piece 8 for closing the end of the slit 9 are provided outside the die adapter 20, the opening width of the slit 9 is Can be performed without any trouble even during the production of the seat 19.

The unnecessary opening of the slit 9 is
Since the second resin b is reliably closed by the closing piece 8, it is possible to prevent the second resin b from leaking from here.

The shape of the slit 9 can be changed variously according to the use and purpose.

In the above embodiment, the slit portion 9 is provided on the resin supply side of the conduit 2, but may be provided on the opposite side (right side in the figure). Further, the closing member may be configured to be pressed toward the conduit by a spring.
Further, the closing member can be formed integrally with the dao adapter.

The thermoplastic resin a used in the present invention
Examples of b include polyethylene, polypropylene, polystyrene, polycarbonate, vinyl chloride resin, nylon resin, polyvinyl acetal, acrylic resin, acetal resin, and polyester resin. A plasticizer, a filler, and the like may be added to these thermoplastic resins.

[0034]

According to the present invention, thermoplastic resin sheets having different shapes of the second resin layer can be produced without stopping production. There is no reduction in productivity and no loss of material for cleaning the mold.

Further, the unnecessary opening of the slit portion of the conduit can be reliably closed to regulate the opening width and the leakage of the second resin can be prevented, so that the thickness deviation of the second resin layer can be eliminated, and the quality can be improved. A good thermoplastic resin sheet can be manufactured.

[Brief description of the drawings]

FIG. 1 is a horizontal sectional view of an apparatus for producing a thermoplastic resin sheet of the present invention.

FIG. 2 is a sectional view taken along line II-II of FIG.

FIG. 3 is a sectional view of a main part of a thermoplastic resin sheet.

FIG. 4 is a horizontal sectional view of a main portion of a conventional thermoplastic resin sheet manufacturing apparatus.

FIG. 5 is a horizontal sectional view of a main part of a conventional thermoplastic resin sheet manufacturing apparatus.

[Explanation of symbols]

 DESCRIPTION OF REFERENCE NUMERALS 1 Extrusion molding die 2 Conduit 3 Manifold 8 Closure member 9 Slit section 13 Second resin supply path 15 Slit-shaped die orifice 20 Die adapter a First thermoplastic resin b Second thermoplastic resin A First resin layer B Second resin layer

Claims (1)

(57) [Claims] 1. A first resin layer formed of a first thermoplastic resin, and a second resin layer having a predetermined width embedded in the first resin layer and formed of a second thermoplastic resin. A manufacturing apparatus for a thermoplastic resin sheet having a resin layer, the apparatus includes an extrusion mold, and a conduit, the extrusion mold,
A manifold to which the first thermoplastic resin is supplied, and a slit-shaped die orifice in which the first thermoplastic resin is pushed out of the manifold to form the first resin layer; The conduit is disposed in the manifold and supported by a mold so as to be movable in the axial direction thereof.
A second resin supply path through which the thermoplastic resin is supplied, and a slit in the manifold where the second resin supply path opens, and closes an end of the slit on the side wall of the mold. An apparatus for manufacturing a thermoplastic resin sheet in which a closing member to be obtained is provided in a mold.