JPH11216757A - Manufacturing method of composite resin sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize the precise formation of resin strips without being influenced by a bank by a method wherein a resin for a resin layer C, which is incompatible with a resin for a resin layer A, is discharged through a slit-like flow path provided towards a composite resin path so as to laminate onto the resin for the resin layer A and finally the resin layer C is separated by means of a group of forming rolls. SOLUTION: A flow path 41 is constituted in a slit having a uniform height in a X-direction. Through this flow path, a flat plate-like resin layer C is formed and laminated onto a resin layer A and discharged from a composite resin efflux port. Next, a resin sheet under a molten state discharged from the composite resin efflux port is pinched between at least one pair of forming rolls so as to extrusion-formed under the condition that the bank of molten resin is formed between at least one surface of the resin sheet, on which the resin layer C is formed, and a forming roll. At this time, the influence by the bank of the molten resin can be prevented by the formation of the resin layer C, resulting in obtaining a sheet having a uniform surface state, thickness or the like. After that, the resin layer C, which is infusible in the resin layer A, is removed by being separated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a composite resin sheet in which flat resin strips are embedded in a streak shape inside a sheet-like resin layer. The present invention particularly relates to a method for manufacturing a light-shielding sheet, a visibility control sheet, a light control sheet, and the like that block light in a certain direction or control a field of view.

[0002]

2. Description of the Related Art A method of coextruding a transparent thermoplastic resin and an opaque thermoplastic resin to produce a light-shielding plate or a light control film in which a large number of transparent portions and opaque portions are alternately laminated (Japanese Unexamined Patent Publication No. Sho 61 (1986)). No. 125846) is known.

[0003]

An operation of extruding a thermoplastic resin in a molten state from an exit of a molding die and then performing imposition with a molding roll is required in the case of shaping many sheets. As one method at this time, a method is employed in which the surface state and thickness of the sheet are made uniform while forming a pool of molten resin (hereinafter referred to as a bank) between one surface of the sheet and a forming roll. .

[0004] The thickness direction Y
, A flow in which the molten resin circulates and reverses occurs, and a secondary flow in the X direction occurs. However, in the above-described conventional technology, since the length of the opaque resin to be laminated matches the thickness of the sheet, it is easily affected by the above-described reverse flow in the bank and the secondary flow of the bank. The formed laminated structure of the transparent resin and the opaque resin is deformed or disturbed, and it is impossible to form a desired shape.

[0005] Therefore, a molding roll cannot be used, and it has been extremely difficult to form an extruded plate. In addition, the sheet manufactured in this manner has an uneven sheet thickness, streaks, irregularities, undulations, small wrinkles, etc. are generated on the surface, and is not at all suitable for purposes such as the view control sheet and the light shielding sheet. Did not. The present invention has been made in view of such circumstances, and its object is to employ extrusion molding of a thermoplastic resin, to have a uniform surface state, a uniform thickness, no appearance defects, a light-shielding sheet, and visibility controllability. An object of the present invention is to provide a method for manufacturing a composite resin sheet suitable for use as a sheet or the like extremely easily.

[0006]

Means for Solving the Problems The gist of the present invention is as follows. It has a predetermined width in the X direction, a predetermined thickness in the Y direction, and a predetermined length in the Z direction, a composite resin flow forming portion (22) at one end in the Z direction, and a composite resin outlet (23) at the other end. A composite resin flow forming section (22) in a composite resin flow path (21) having
, A plurality of flow paths (31) for causing the resin for resin strip B to flow out in the Z direction, and a plurality of flow paths (31).
And a plurality of flow paths (35, 36) for allowing the resin for the resin layer A to flow out from both sides of the XZ plane toward the composite resin flow forming section (22). The paths (31) are arranged at predetermined intervals in the X direction, and the XZ section of the two rows of flow paths (35, 36) of the resin for the resin layer A is Z
It has a shape in which portions Rn and Ln having a large height in the direction and portions Rm and Lm having a small height (including zero) in the Z direction are alternately arranged, and is combined with the composite resin flow forming portion (22). A slit-shaped flow path (41) for flowing out the resin for the resin layer C, which is incompatible with the resin for the resin layer A, toward the composite resin flow path (21) between the resin flow port (23), Using a device provided on at least one side of the XZ plane including the plurality of resin strip B resin flow paths (31), the resin for the resin layer A is transferred from the flow paths (35, 36) to the resin strips. The resin for B flows out from the flow path (31) to the composite resin flow forming section (22), and then the resin for the resin layer C flows from the flow path (51) to the composite resin flow path (2).
1) to form a composite resin flow, extruded as a molten laminated sheet from the composite resin outlet (23), and sandwiched the molten laminated sheet between at least one pair of forming rolls. A method of manufacturing a composite resin sheet, comprising extruding a molten resin between at least one surface on which a layer C is formed and a forming roll while forming a pool of molten resin, and then peeling off the resin for the resin layer C ( 1. first method), and It has a predetermined width in the X direction, a predetermined thickness in the Y direction, and a predetermined length in the Z direction, a composite resin flow forming portion (52) at one end in the Z direction, and a composite resin outlet (53) at the other end. The composite resin flow forming section (52) in the composite resin flow path (51) having
, A plurality of slit-shaped flow channels (61) arranged to face the XY plane of the composite resin flow forming portion (52) to allow the resin for resin strip B to flow out, and a plurality of slits to allow the resin for resin layer A to flow out. A slit-shaped flow path (65), wherein the slit-shaped flow path (61) and the flow path (65) are alternately arranged in parallel with the Y direction or alternately at a predetermined angle in the Y direction to form a composite resin flow. In the portion (52), the projected length Lb of the resin channel B resin flow path (61) in the Y direction is the resin layer A.
Length of the resin flow path (65) in the Y direction is shorter than the composite resin flow forming portion (52) and the composite resin outlet (5).
3) toward the composite resin flow path (51).
Flow path (71) through which the resin for the resin layer C incompatible with the resin for flow out flows, including the flow paths (61, 65).
Using a device provided on at least one side of the Z plane,
The resin for the resin layer A flows out of the flow path (65) and the resin for the resin strip B flows out of the flow path (61) to the composite resin flow forming section (52). ) To the composite resin flow path (51) to form a composite resin flow, and extrude from the composite resin outlet (53) as a molten resin sheet. The molten resin sheet is placed between at least one pair of forming rolls. And extrusion molding while forming a pool of molten resin between at least one surface of the resin sheet on which the resin layer C is formed and the forming roll, and thereafter, the resin for the resin layer C is peeled off. Manufacturing method of resin sheet (second method).

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings. FIG. 1 is a cross-sectional view showing some examples of a composite resin sheet obtained by the method of the present invention, and is a partial cross-sectional view along an XY plane perpendicular to the Z direction which is the extrusion direction. A plurality of flat resin strips B are buried and arranged inside the resin layer A, and are disposed parallel to the Y direction of the sheet or parallel to each other at a predetermined angle φ with respect to the Y direction.

FIG. 2 is a cross-sectional view showing an example of a laminated sheet of a resin layer A and a resin layer C made of a resin that is incompatible with the resin of the resin layer A. FIG. 3 is a schematic plan view showing one embodiment of an extrusion molding apparatus useful for carrying out the method according to the present invention, and FIG. 4 is a schematic side view of the apparatus of FIG. FIG.
And FIG. 4, a resin layer A formed as a base resin
The resin for use is melt-extruded into the shaping head (5) by the extruder (1) and reaches the metering pump (3). The resin shaped as the flat resin strip B is melt-extruded into the shaping head (5) by the extruder (2), and reaches the metering pump (4). The resin to be shaped as the resin layer C is melt-extruded into the shaping head (5) by the extruder (17) and guided to the metering pump (18).

Each resin is a metering pump (3),
The flow rate is adjusted in (4) and (18), and the composite is formed through respective flow paths incorporated in the die pack (6), and is extruded from the composite outlet (23) in the die pack (6). Next, the resin layer C is formed by a forming roll group (10), and thereafter, the resin layer C is peeled and removed by a peeling device (16), and cut into a predetermined length by a sheet cutting machine (15). The peeling and removal of the resin layer C may be performed after the sheet is cut.

FIG. 5 is a schematic plan sectional view showing an example of the formation of the composite resin flow and the internal structure of the extruding device in the extruding device shown in FIGS. It is useful to carry out the first method according to the above. FIG. 6 is a sectional view taken along line II of FIG. FIG. 7 is a perspective view taken along the line II-II in FIG.

FIG. 8 is a sectional view taken along line III-III in FIG. FIG. 9 is a sectional view taken along line IV-IV in FIG. 5 to 9, the resin for resin strip B is
The resin layer A is discharged from the plurality of flow paths (31) formed in the same XZ plane into the composite resin flow forming section (22).
The resin for the resin is also discharged to the composite resin flow forming section (22) by the two rows of flow paths (35, 36) from both sides of the resin for the resin strip B discharged to the composite resin flow forming section (22). The plurality of resin strips B deformed into a predetermined flat shape in the resin flow forming section (22) are guided to the downstream side of the composite resin flow path (21) while being buried and disposed therein.

X of the flow path (35, 36) of the resin for the resin layer A
The Z section has portions Rn and Ln having a large height in the Z direction, and Z
The portions Rm and Lm having small heights (including zero) in the direction have a shape in which the portions Rm and Lm are alternately arranged. 35,
36) and the plurality of flow paths (31) for allowing the resin strip B resin to flow in the Z direction, the resin strip B acts on the XY plane by the flow of the resin layer A resin. And the like, the cross-sectional shape is transformed into a desired flat shape.

A feature of this method according to the present invention is that, first, a composite resin flow forming section (22) included in the above-described apparatus and method.
Between the composite resin outlet (23) and the composite resin outlet (23).
Toward 1), a slit-shaped flow path (41) for letting out the resin for the resin layer C is provided, and secondly, a resin incompatible with the resin for the resin layer A through the flow path (41). The point is that the resin for layer C is discharged to laminate the resin layer C on the resin layer A, and thirdly, the resin layer C is peeled off after being formed by the forming roll group (10).

The flow channel (41) has a slit shape in which the height of the slit is uniform in the X direction in the XZ cross section, whereby a flat resin layer C is formed, and an example thereof is shown in FIG. The resin sheet in which the resin layer C is laminated on the resin layer A is discharged from the composite resin outlet (23). The molten resin sheet discharged from the composite resin outlet (23) is sandwiched between at least one pair of forming rolls, and a bank of molten resin is formed between at least one surface of the resin sheet on which the resin layer C is formed and the forming roll. Extrusion molding is performed.

FIG. 10 is a schematic plan sectional view showing another example of the formation of the composite resin flow and the internal structure of the extruder unit in the extruder shown in FIGS. 3 and 4. The extruder having such a structure is shown in FIG. It is useful for performing the second method according to the present invention. FIG. 11 is a sectional view taken along line II in FIG. FIG. 12 is a sectional view taken along the line II-II in FIG.
It is arrow sectional drawing of the line.

As shown in FIGS. 10 to 12, on the XY plane of the composite resin flow forming section (52) of the composite resin flow path (51), the resin flow path (65) for the resin layer A and the resin strip B are formed. It is arranged alternately with the flow path (61) of the application resin. In the composite resin flow forming section (52), the projected length Lb of the resin channel B resin flow path (61) in the Y direction is the same as that of the resin layer A resin flow path (65) in the Y direction. The resin for the resin layer C flows out toward the composite resin flow path (51) between the composite resin flow forming section (52) and the composite resin flow outlet (53). Slit-shaped flow path (7
1) is formed.

The resin for the resin layer A is discharged through a plurality of slit-shaped flow paths (65) arranged at predetermined intervals in the X direction. On the other hand, the resin for resin strip B has a plurality of slit-shaped flow paths (61) arranged at predetermined intervals in the X direction.
To form a flow of a resin strip B having a predetermined flat shape, dimensions, and the like. Composite resin flow forming section (5
In 2), by setting the ejection direction of the resin for the resin layer A and the ejection direction of the resin for the resin strip B to be the same direction, interference due to the flow of both resins is prevented, and the ejection shape of the resin for the resin strip B is reduced. It is not deformed by the flow of the layer A resin.

The features of this second method according to the present invention also include, firstly, the composite between the composite resin flow forming section (52) and the composite resin outlet (53) included in the above-described apparatus and method. A slit-shaped flow path (71) for discharging the resin for the resin layer C is provided toward the resin flow path (51). The point is that the resin layer C is laminated on the resin layer A by discharging the resin for the resin layer C which is soluble, and the resin layer C is peeled off after the third molding by the molding roll group (10).

The flow path (71) has a slit shape in which the height of the slit is uniform in the X direction in the XZ cross section, whereby a flat resin layer C is formed, and an example thereof is shown in FIG. The resin sheet in which the resin layer C is laminated on the resin layer A is discharged from the composite resin outlet (53). The molten resin sheet discharged from the composite resin outlet (53) is sandwiched between at least one pair of forming rolls, and a bank of molten resin is formed between at least one surface of the resin sheet on which the resin layer C is formed and the forming roll. Extrusion molding is performed.

FIG. 13 shows the state of the molten resin sheet from the composite resin outlets (23, 53) of the die pack (6) to the forming roll (10) in the first and second methods according to the present invention. It is a schematic diagram for demonstrating. The molten resin sheet (81) extruded from the composite resin outlet forms a bank (82) while being sandwiched between at least one pair of forming rolls (10). At this time, the influence of the bank of the molten resin can be prevented by forming the resin layer C, whereby a sheet having a uniform surface state and thickness can be obtained. The thickness of the resin layer C can be arbitrarily set, but is preferably determined in consideration of the influence of the circulation flow of the molten resin in the bank portion and the like.

Thereafter, the resin layer C which is incompatible with the resin layer A is peeled off to obtain a composite resin sheet as shown in FIG. In the composite resin sheet obtained by the method of the present invention, the flat resin strip B is used.
Is formed almost to the surface of the sheet as shown in the figure. For example, if the same light-shielding property is to be imparted, the sheet can be formed thin. Further, when it is intended to impart a desired function by reflecting or refracting light passing through the inside of the sheet by the resin strip B, the function can be more efficiently imparted.

As the resin for the resin layer A applicable to the present invention, a wide range of thermoplastic resins can be used, and various acrylic resins represented by polyethylene terephthalate, polyvinyl chloride, polystyrene, polycarbonate and polymethyl methacrylate can be used. Base resin, amorphous polyolefin, polyamide, polymethylpentene, a copolymer resin thereof, a blend resin and the like. When transparency, weather resistance and the like are particularly required, an acrylic resin is preferable, and polymethyl methacrylate is the most preferable material.

As the resin for the resin layer B, the resins exemplified for the resin layer A can be used similarly.
It is selected in consideration of the adhesion to the resin layer A and the like. In order to impart light-shielding properties to the resin strip B, various pigments, for example, carbon black, titanium oxide, and other materials can be added to the opaque resin or the transparent resin described above. A transparent resin having a different refractive index from that of the resin layer A can be used for the resin strip B to cause reflection and refraction of light on the surface of the resin strip B.

The resin for the resin layer B, which is incompatible with the resin for the resin layer A, preferably has good peelability.
Specific examples thereof include, depending on the combination with the resin for the resin layer A, for example, polypropylene, polystyrene, polyisobutylene, polybutadiene, polyamide, polyethylene, modified polyethylene, copolymerization of ethylene with another olefin-based resin. Coalescence and the like.

[0025]

The present invention will be described in detail with reference to the following examples. Example 1 Polymethyl methacrylate (Acrypet MD, manufactured by Mitsubishi Rayon Co., Ltd.) as a resin for the resin layer A, and polyethylene (Hisex, manufactured by Mitsui Petrochemical Co., Ltd.) as a resin for the resin layer C,
Polymethyl methacrylate containing carbon black was prepared as a resin for resin strip B.

A co-extrusion molding apparatus having the structure shown in FIGS. In the resin flow paths (31) for the plurality of resin strips B, the inner diameter of the discharge port was 0.45 mm, and the interval between adjacent discharge ports was 2 mm. The resin flow path for the resin layer A (35, 3
6) The heights △ Rm and △ Lm of the portions Rm and Lm are each zero, the heights △ Rn and △ Ln of the portions Rn and Ln are each 1 mm, and the widths of the portions Rm and Rn are each 1 mm, and the portions Lm and Lm. The width of Ln was 1 mm.

The gap between the slits of the resin flow path (41) for the resin layer C was uniformly made 0.5 mm in the x direction. The resin for resin layer A is melted by the first extruder (1), the resin for resin layer C is melted by the second extruder (17), and the resin for resin strip B is melted by the third extruder (2). And dispensed in the shaping head (5). The resin for the resin layer A is discharged from the flow path (35, 36), the resin for the resin strip B is discharged from the flow path (31), and the resin for the resin layer C is discharged from the flow path (51). .

Co-extrusion at a shaping temperature of 240 ° C., forming with a forming roll, continuously producing a laminated sheet having a thickness of 4 mm × 500 mm width, and then peeling off the resin layer C to form a laminated sheet of 2 mm
A thick composite resin sheet was obtained. The obtained sheet is a transparent sheet having a smooth surface, and each of the resin strips B has a thickness of about 0.1 mm.
It had a thickness of 07 mm and a length of about 2.5 mm, and was formed parallel at an angle of about 45 degrees to the sheet surface and at an interval of 2 mm.

Example 2 A co-extrusion molding apparatus having a structure as shown in FIGS. 3, 4, and 10 to 12 was used. The slit-shaped flow paths (65) for the resin layer A and the slit-shaped flow paths (61) for the resin strip B are alternately arranged in parallel with the Y direction, and the flow path for the resin strip B (6
The arrangement pitch of 1) is 0.5 mm and the slit gap is 0.01
mm, the length Lb is 1.8 mm, and the flow path for the resin layer A (65)
The slit gap was 0.01 mm, and the slit length La was 2 mm. The width of the composite resin channel was 500 mm in the X direction, and the thickness q in the Y direction was 2 mm.

The same resin as in Example 1 was used as the resin for the resin layer A, the resin for the resin layer C, and the resin for the resin strip B, respectively. The resin for resin layer A is melted by the first extruder (1), the resin for resin layer C is melted by the second extruder (17), and the resin for resin strip B is melted by the third extruder (2). And dispensed in the shaping head (5).

The resin for the resin layer A is discharged from the flow path (65), the resin for the resin strip B is discharged from the flow path (61), and the resin for the resin layer C is discharged from the flow path (71). did. Co-extruding at a shaping temperature of 240 ° C., forming by a forming roll, continuously producing a laminated sheet having a thickness of 4 mm × 500 mm, and then peeling off the resin layer B to obtain a composite resin sheet having a thickness of 2 mm. Was.

The obtained sheet is a transparent sheet having a smooth surface, and the resin strips B have a thickness of about 0.01 mm and a length of about 1.8 mm, respectively, and are spaced at 0.5 mm intervals in the Y direction. Was formed in parallel with.

[0033]

According to the present invention, a light-shielding sheet, a visibility control sheet, and a plurality of resin strips formed accurately to near the surface without being affected by a molten bank in extrusion molding.
A resin sheet suitable for various purposes and uses such as a light control sheet can be produced very simply and with high productivity in one step.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing some examples of a composite resin sheet obtained by the method of the present invention.

FIG. 2 is a sectional view showing an example of a laminated sheet of a resin layer A and an incompatible resin layer C.

FIG. 3 is a schematic plan view showing one embodiment of an extrusion molding apparatus useful for carrying out the method of the present invention.

FIG. 4 is a schematic side view of the apparatus of FIG.

FIG. 5 is a schematic plan cross-sectional view showing an example of the formation of the composite resin flow and the internal structure of the extruding device part in the extrusion molding devices of FIGS. 3 and 4.

FIG. 6 is a sectional view taken along line II of FIG. 5;

FIG. 7 is a perspective view taken along the line II-II in FIG. 6;

FIG. 8 is a sectional view taken along line III-III in FIG. 6;

9 is a sectional view taken along line IV-IV in FIG.

FIG. 10 is a schematic plan cross-sectional view showing another example of the formation of the composite resin flow and the internal structure of the extruder unit in the extruder shown in FIGS. 3 and 4.

FIG. 11 is a sectional view taken along the line II in FIG. 10;

FIG. 12 is a sectional view taken along the line II-II in FIG. 11;

FIG. 13 is a schematic diagram for explaining a state of a resin sheet in a molten state from a composite resin outlet to a forming roll.

[Explanation of symbols]

 21, 51 ... composite resin flow path 22, 52 ... composite resin flow forming part 23, 53 ... composite resin flow outlet 31, 61 ... resin flow path for resin strip B 35, 36, 65 ... resin flow path 41 for resin layer A , 71 ... resin flow path for resin layer C

Claims (2)

[Claims] 1. A predetermined width in the X direction, a predetermined thickness in the Y direction, and a predetermined length in the Z direction, a composite resin flow forming portion (22) at one end in the Z direction, and a composite at the other end. A plurality of flow paths (31) for allowing resin for resin strip B to flow out in the Z direction in a composite resin flow forming section (22) in a composite resin flow path (21) having a resin outlet (23); And XZ including a plurality of flow paths (31)
Two rows of flow paths (35, 3) through which the resin for resin layer A flows out from both sides of the plane toward the composite resin flow forming section (22).
6), the flow paths (31) of the plurality of resin strips B are arranged at predetermined intervals in the X direction, and the XZ cross section of the two rows of flow paths (35, 36) of the resin for the resin layer A is Z It has a shape in which portions Rn and Ln having a large height in the direction and portions Rm and Lm having a small height (including zero) in the Z direction are alternately arranged, and is combined with the composite resin flow forming portion (22). A slit-shaped flow path (41) for flowing out the resin for the resin layer C, which is incompatible with the resin for the resin layer A, toward the composite resin flow path (21) between the resin flow port (23), A plurality of resin flow paths for resin strip B (3
Using a device provided on at least one side of the XZ plane including 1), the resin for the resin layer A is compounded from the channels (35, 36) and the resin for the resin strip B is compounded from the channel (31). Resin flow forming part (22)
And then the resin for the resin layer C is caused to flow out of the flow path (41) into the composite resin flow path (21) to form a composite resin flow,
The composite sheet is extruded from the composite resin outlet (23) as a molten laminated sheet. The molten laminated sheet is sandwiched between at least one pair of forming rolls, and at least one surface of the resin sheet on which the resin layer C is formed and the forming roll. A method for producing a composite resin sheet, comprising extruding a resin layer while forming a pool of molten resin therebetween, and thereafter peeling off the resin for the resin layer C. 2. It has a predetermined width in the X direction, a predetermined thickness in the Y direction, and a predetermined length in the Z direction, a composite resin flow forming portion (52) at one end in the Z direction, and a composite at the other end. In the composite resin flow forming section (52) in the composite resin flow path (51) having the resin outlet (53), the resin for the resin strip B disposed facing the XY plane of the composite resin flow forming section (52). And a plurality of slit-shaped flow paths (65) through which the resin for the resin layer A flows out, and a plurality of slit-shaped flow paths (65) through which the resin for the resin layer A flows out. ) Are parallel to the Y direction or alternately arranged at a predetermined angle in the Y direction, and the projected length of the resin strip B resin flow path (61) in the Y direction in the composite resin flow forming portion (52). Lb
Is shorter than the projection length La of the resin flow path (65) in the Y direction for the resin for the resin layer A, and the composite resin flow path (51) between the composite resin flow forming part (52) and the composite resin outlet (53). ), A slit-shaped flow path (71) through which the resin for the resin layer C is incompatible with the resin for the resin layer A is provided on at least one side of the XZ plane including the flow paths (61, 65). Using the device provided, the resin for the resin layer A flows out of the flow path (65) and the resin for the resin strip B flows out of the flow path (61) to the composite resin flow forming section (52). The resin for flow is caused to flow out of the flow channel (71) into the composite resin flow channel (51) to form a composite resin flow, and is extruded from the composite resin outlet (53) as a molten resin sheet. The resin layer C of the resin sheet is sandwiched between at least one pair of forming rolls. And one surface Kutomo between molding rolls, extrusion molding while forming a pool of molten resin, the manufacturing method of the resin sheet, which comprises peeling the resin layer C for the resin thereafter.