JPH0683327U - I-die - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide an I-die that can change the width of a film while performing continuous molding. [Configuration] An I-die that includes a flow path for molten polymer that runs from the die inlet to one end (side end) of a manifold, a manifold that spreads the molten polymer from said flow path in the die width direction, a lip land located at the open end of the manifold to regulate the flow of molten polymer, and a lip located at the tip of the lip land to extrude the molten polymer to a predetermined width and thickness, wherein inner deckles that can move freely back and forth in the die width direction and that regulate the flow of molten polymer at the side ends are provided at both side ends of the manifold, lip land, and lip, and the width of the extruded film can be adjusted by moving the inner deckles.

Description

[Detailed description of the invention]

[0001]

[Industrial application field]

This invention relates to an I-die with adjustable film width, and more specifically to an I-die having inner deckles at both ends which can move freely in the die width direction and regulate the flow of molten polymer at both ends, and which adjusts the width of the extruded film by moving the inner deckles.

[0002]

2. Description of the Related Art

Conventionally, in extrusion molding of films, the width of the molded film is determined by the widthwise lengths of the manifold, lip land, and lip of the I-die. Therefore, when changing the width of the molded film, the usual method has been to interrupt continuous molding and replace it with an I-die having manifold, lip land, and lip lengths appropriate for the film width.

[0003]

[Problem that the invention aims to solve]

However, in the method of replacing the I-die with one having a manifold, lip land, and lip width length that will result in a specified film width, the film cannot be cut and the film cannot be continuously molded, and it takes a long time to replace the I-die, which causes a decrease in the operating rate of the film production equipment. In addition, after replacing the I-die and resuming molding, it takes a long time until the molding becomes stable and the product film can be obtained. Since the film extruded until the molding becomes stable cannot be supplied as a product, the polymer raw material is wasted, which is a problem of loss of economic efficiency.

An object of the present invention is to solve the above-mentioned problems and to provide an I-die which can change the width dimension of a film while performing continuous molding without cutting and without changing the die.

[0005]

[Means for solving the problem]

The object of the present invention is achieved by an I-die having a molten polymer flow path from the die inlet to one end (side end) of a manifold, a manifold that spreads the molten polymer from the flow path in the die width direction, a lip land located at the open end of the manifold to regulate the flow of the molten polymer, and a lip located at the tip of the lip land to extrude the molten polymer to a predetermined width and thickness, characterized in that inner deckles are provided at both side ends of the manifold, lip land, and lip, which can freely move back and forth in the die width direction and regulate the flow of the molten polymer at the side ends, and the width direction of the extruded film is adjusted by the movement of the inner deckles.

[0006]The present invention will now be described with reference to the drawings.

[0007] Figure 1 is a front cross-sectional view of a film width adjustment type I-die showing one example of the present invention. In Figure 1, 1 is a die body, 2 is a flow path of the molten polymer from the die inlet to one end (side end) of the manifold, 3 is a manifold that spreads the molten polymer, 4 is a lip land that regulates the flow of the molten polymer, 5 is a lip, 6 and 6' are inner deckles that regulate the flow of the molten polymer, and 7 and 7' are devices that move the inner deckles 6 and 6' in the die width direction.

[0008] As shown in Figure 1, molten polymer supplied from a melt extruder (not shown) passes through a molten polymer flow path 2 from the die inlet, is developed in a manifold 3, passes through a lip land 4, and is extruded in the form of a film from a lip 5. At this time, since a normal die does not have a function for adjusting the film width, when the width of the film is to be changed, the die body 1 must be replaced, which interrupts continuous molding and reduces the operating rate of the film production equipment.

[0009] In the I-die of the present invention, to adjust the film width, inner deckles 6, 6' that can be moved in the die width direction by moving devices 7, 7' are provided at both ends of the manifold 3, lip land 4, and lip 5. By moving the inner deckles 6, 6' in the die width direction, the film width can be changed during continuous molding without replacing the die body.

[0010] An example of a cross-sectional shape from the manifold 3 to the lip 5 in the I-die is shown in Figures 2 to 5, where Figures 2 and 4 are side cross-sectional views taken along line A-A in Figure 1, and Figures 3 and 5 are side cross-sectional views taken along line B-B in Figure 1. In Figures 2 to 5, only the inner deckle is shaded to facilitate understanding. Figures 4 and 5 are modified versions of Figures 2 and 3, respectively. In Figures 2 and 4, the inner deckle 6 is shaped to block the molten polymer from flowing into a part of the lower side (opening side) of the manifold 3, the lip land 4, and the entire lip 5. In Figures 3 and 5, the inner deckle 6' is shaped to block the molten polymer from flowing into the manifold 3, the lip land 4, and the entire lip 5.

[0011] Thermoplastic polymers useful for producing films using the I-die of the present invention may be any polymer capable of forming a film, representative examples of which include polyethylene terephthalate, polybutylene terephthalate, polyethylene-2,6-naphthalenedicarboxylate, high density polyethylene, polypropylene, nylon 6, nylon 66, etc. These may be used alone or in combination of two or more.

[0012]

[Effects of the invention]

According to the present invention, it is possible to provide an I-die in which the film width can be changed by adjusting the positions of the inner deckles 6, 6'.

[Brief description of the drawings]

FIG. 1 is a front cross-sectional view of an I-die showing an example of the present invention.

2 is a side cross-sectional view showing an example of a shape from a manifold to a lip taken along line AA in FIG.

3 is a side cross-sectional view showing an example of a shape from a manifold to a lip taken along line BB in FIG. 1;

4 is a side cross-sectional view showing an example of a shape from a manifold to a lip taken along line AA in FIG.

5 is a side cross-sectional view showing an example of a shape from a manifold to a lip taken along line BB in FIG.

[Explanation of symbols]

Reference Signs List 1 Die body 2 Polymer flow path 3 Manifold 4 Lip land 5 Lip 6, 6' Inner deckle 7, 7' Inner deckle moving device

Claims (1)

[Scope of utility model claims] [Claim 1] An I-die comprising a flow path for molten polymer from the die inlet to one end (side end) of a manifold, a manifold which spreads the molten polymer from said flow path in the die width direction, a lip land located at the open end of the manifold which regulates the flow of molten polymer, and a lip located at the tip of the lip land which extrudes the molten polymer to a predetermined width and thickness, wherein inner deckles are provided at both side ends of the manifold, lip land and lip which can move freely back and forth in the die width direction and which regulate the flow of molten polymer at the side ends, and the width dimension of the extruded film is adjusted by moving the inner deckles.