JP2002331580A - Manufacturing method of embossed sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method enabling continuous, easy, inexpensive and stable manufacture of an embossed sheet excellent in transferability. SOLUTION: In a manufacturing method for the embossed sheet, a woven fabric is brought into pressure contact, in the shape of a circular arc, with one or both surfaces of a sheetlike material of a thermoplastic resin extruded in a molten state from a T-die, between a forming roll and a metal endless belt, and then the woven fabric is peeled off from the sheetlike material of the thermoplastic resin.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for producing a thermoplastic resin embossed sheet.

[0002]

2. Description of the Related Art Sheets made of thermoplastic resin as a main raw material have been used in various fields for a long time, and are mainly produced by a T-die extrusion molding method. The sheet is provided with an embossed pattern for the purpose of improving design, preventing blocking between the sheets, improving damage resistance, and the like. Usually, the embossed pattern is provided by a roll in which the embossed pattern is engraved (hereinafter, referred to as an embossed roll).
This is performed by a method of giving an embossed pattern to a sheet. Further, as a method for improving the transferability of an embossed pattern to a sheet, there is known a method of applying a surface pressure using an embossing roll and a metal endless belt (Japanese Patent Laid-Open No. 9-164592).

However, when the continuous operation is performed, the molten resin adheres to the embossing roll, and the design of the embossed sheet obtained is impaired. Therefore, the resin adhering to the embossing roll must be washed away with a solvent,
There is a problem that the basic unit deteriorates. Also, it is necessary to stock a plurality of expensive embossing rolls for giving various embossing patterns.

[0004] Therefore, there is no need to stock expensive embossing rolls, and as a method of transferring embossing that can be operated continuously, Japanese Patent Publication No. 7-25190 discloses a method of extruding a releasable resin by paper, non-woven fabric, woven fabric or the like. Laminating material for extruding between a sheet having a three-dimensional pattern and a substrate, sandwich-laminating using a press roll, and separating the sheet after cooling to transfer the three-dimensional pattern to the release resin surface. Is disclosed. By the manufacturing method,
The embossed sheet can be manufactured continuously, easily and at low cost.

[0005] However, in this manufacturing method, since the transfer step is performed only at the contact points between the press rolls, pressure bonding may not be sufficient, or air may be mixed in, resulting in poor transfer of the three-dimensional pattern. Therefore, even now, embossed sheets are mainly manufactured by a method using emboss rolls. That is, there is a demand for a method capable of continuously, easily, inexpensively, and stably producing an embossed sheet having good transferability.

[0006]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to solve the above-mentioned problems, and as a result, in the production of an embossed sheet by T-die extrusion molding, a T-die is used instead of an embossing roll. The woven fabric fed from one or both sides of the extruded thermoplastic molten resin is pressed in an arc between a forming roll and a metal endless belt to form the molten resin and the woven fabric into a laminated sheet, and then the woven fabric is peeled by a release roll. The method of transferring the texture pattern of the woven fabric to the surface of the thermoplastic resin sheet to obtain an embossed sheet is more stable than the conventional embossing method, and the embossed sheet is continuously transferred. The present inventors have found that this is a useful manufacturing method that can be easily and inexpensively manufactured, and have completed the present invention.

The present invention is described below. 1. After pressing a woven fabric on one or both sides of a thermoplastic resin sheet extruded in a molten state from a T-die in an arc shape between a forming roll and a metal endless belt, the woven fabric is formed into a thermoplastic resin sheet. A method for producing an embossed sheet, wherein the embossed sheet is peeled off from an object. 2. The above-described first aspect, wherein the forming is performed by crimping at least 100 mm in an arc shape at least in a sheet traveling direction with a pressing force of 5 MPa or more between a forming roll and a metal endless belt.
The method for producing an embossed sheet according to the above item.

[0008]

Embodiments of the present invention will be described below. The method for producing an embossed sheet of the present invention is performed by the apparatus illustrated in FIGS. 1 and 2. First, a thermoplastic resin is melted and kneaded by a T-die extruder 1 and extruded as a sheet material 8. Feeding device 2 from one or both sides of extruded thermoplastic resin sheet 8
The forming roll 3 and the metal endless belt 5 are overlapped with the woven fabric 9 fed out using
And pressed by the forming rolls 3 and 3 ′.
Thereafter, the woven fabric 9 and the thermoplastic resin sheet material 8 are separated from the forming rolls 3 and 3 ′ by the contact between the forming rolls 3 and 3 ′.
Endless belt 5 pressed on the circumference of the forming roll 3 by the forming roll 3 ′ and the pressure roll 4
And the molten resin is cooled and solidified, and the thermoplastic resin sheet 8 and the woven fabric 9
Is a laminated sheet, and at the same time, the texture of the woven fabric is transferred to the thermoplastic resin sheet 8. Thereafter, the woven fabric 9 is peeled off from the laminated sheet by the peeling roll 6, and the embossed sheet 10 is obtained.

In the production method of the present invention, the embossed sheet 10 can be annealed by the annealing roll 7. It is preferable to perform annealing from the surface of the embossed sheet 10 from which the curl is removed.
It is easy for those skilled in the art to optimize the number, shape, annealing temperature, etc. of the annealing rolls.

According to the production method of the present invention, the thermoplastic resin sheet extruded from the T-die is formed into a multilayer sheet or a base sheet is fed from one of the feeding devices 2 instead of the woven fabric. Also, a multilayer embossed sheet can be manufactured.

The thermoplastic resin used in the present invention may be any resin that is usually used in a T-die extrusion molding method. Examples of the thermoplastic resin include polyvinyl chloride resin, polyvinylidene chloride resin, polyolefin resin, ethylene-vinyl acetate copolymer resin, ethylene- (meth) acrylic acid (ester) copolymer resin, and ethylene-vinyl alcohol copolymer. A coalescing resin and a polystyrene resin can be mentioned.
In the present invention, these resins can be used alone or in combination of two or more. The polyolefin-based resin is a lower α-olefin homopolymer (eg, polyethylene, polypropylene, polybutene), a random or block copolymer with another α-olefin containing a lower α-olefin as a main component, or a mixture thereof. is there. Here, the term “main component” refers to the component having the highest content in the copolymer.

If necessary, known additives may be added to the above-mentioned thermoplastic resin as long as the effects of the present invention are not impaired. Examples of the additives include a stabilizer, an antiblocking agent, a slip agent, an antistatic agent, a weathering agent, a flame retardant, an inorganic filler, and a coloring agent.

The woven fabric used in the present invention may be any fabric that does not undergo a change in shape due to heat, such as burning, fusion welding, and shrinkage, when pressed against a molten thermoplastic resin.
The woven fabric can be reused even after peeling and collection. As a material of the woven fabric, natural fibers, chemical fibers, and composite fibers thereof can be used. Examples of natural fibers include cotton, silk, and hemp.
Examples of the chemical fiber include rayon, acrylic, and polyester. Fiber thickness and weave,
The roughness of the weave is not particularly limited. These are determined by the pattern transferred to the sheet.

The T-die extruder 1 for kneading the resin used in the present invention may be any known and publicly used apparatus. A person skilled in the art can easily optimize the shape of the cylinder or screw depending on the resin to be kneaded, the kneading conditions, and the like. Further, depending on the configuration of the sheet, a known and publicly used feed block or a manifold type T-die for co-pressing can be used. A person skilled in the art can easily select an optimal T-die according to the configuration of the sheet.

In the present invention, the woven fabric 9 is fed from one or both sides of the thermoplastic sheet material 8 by the accompanying feeding device 2. It is preferable to attach a tension controller to the feeding device 2 in order to perform stable pressure bonding.

As the forming rolls 3 and 3 'used in the present invention, metal rolls and rubber rolls can be used.

When the thermoplastic resin sheet 8 and the woven fabric 9 are pressed in an arc shape in a circular arc, the length of the sheet in the traveling direction (hereinafter, may be simply referred to as the pressed length) is an effect of the present invention. There is no particular limitation as long as it is within a range that does not impair certain adhesiveness or emboss transferability and is within a range that is possible in the structure of the manufacturing apparatus. By adjusting the diameter of the pressing roll, the length when the thermoplastic resin sheet material 8 and the woven fabric 9 are pressed in an arc shape can be adjusted. The lower limit of the length is preferably 100 mm, more preferably 260 m
m.

The pressing force at the time of pressing the thermoplastic resin sheet material 8 and the woven fabric 9 is not particularly limited as long as the adhesiveness and the emboss transfer property, which are the effects of the present invention, are not impaired. Preferably it is 5 MPa or more. More preferably, 1
It is 0 MPa or more.

The pressing temperature (the temperature of the forming rolls 3 and 3 ′ and the temperature of the metal endless belt 5) at the time of pressing the thermoplastic resin sheet 8 and the woven fabric 9 is set at the same level.
Any range may be used as long as it does not impair the adhesiveness and emboss transferability of the woven fabric 9 to the woven fabric 9 and does not prevent cooling and solidification of the molten resin. The lower limit of the temperature is preferably 10 ° C, more preferably 30 ° C. The upper limit of the temperature is preferably 100 ° C, more preferably 90 ° C.

The line speed in the pressing step of the present invention is:
Any range may be used as long as the adhesion between the thermoplastic resin sheet material 8 and the woven fabric 9 and the emboss transfer property are not impaired, and the stable operation of the apparatus is not hindered. The lower limit of the line speed is preferably 0.1 m / min, more preferably 1 m / min. The upper limit of the line speed is preferably 100 m / min, more preferably 50 m / min.

In addition to the above-mentioned facilities, the embossed sheet manufacturing apparatus used in the present invention may be any of the known and publicly used apparatuses used for normal thermoplastic resin sheet manufacturing, if necessary, such as cooling rolls, guide rolls, take-up rolls, and the like. A corona treatment machine, a trimming cutter, a fixed-size cutting cutter, a winding machine and the like can also be used.

[0022]

EXAMPLES The present invention will now be described specifically with reference to examples, but the present invention is not limited to these examples. In addition, the evaluation in an Example was performed by the following method. Adhesion evaluation By visual evaluation, in the compression bonding process, x indicates that a poor appearance was observed due to mixing of air or insufficient adhesion between the thermoplastic resin surface or the thermoplastic resin and the woven fabric, and o indicates no appearance. evaluated. Evaluation of Transferability An embossed sheet having a length of 50 m was manufactured according to the present invention, and it was visually evaluated whether or not the embossed surface of the sheet had an embossed portion. The evaluation criterion was evaluated as ○ when no emboss loss was observed within 50 m, and evaluated as × when emboss loss was found even at one location.

Example 1 T-die extruder (65 mm single screw extruder, T-die width 600)
mm), a polypropylene resin (trade name: Chisso Polypro A5014, manufactured by Chisso Corporation) was extruded at a resin temperature of 245 ° C. at a T-die outlet. A woven fabric (a plain weave of 56 tex flax yarn) is unwound from above the melted polypropylene resin sheet, and a crimping roll (metal (mirror surface) roll, φ500 mm × 700 mm) with the melted polypropylene resin sheet and the woven fabric overlapped And a metal endless belt (0.65 mmt × 600 mmw × 6 m), and pressed in an arc shape under the conditions of a pressure force of 10 MPa and a pressure length of 260 mm to obtain a laminated sheet. The woven fabric was peeled off from the obtained laminated sheet with a peeling roll to obtain a polypropylene embossed sheet having a thickness of 0.3 mmt. The obtained polypropylene embossed sheet was annealed at 70 ° C. with two annealing rolls, and then wound up by a winder until the total length became 50 m. Table 1 shows the operating conditions of the embossed sheet manufacturing apparatus. Poor adhesion and air mixing were not observed in the obtained laminated sheet. Also, in the obtained embossed sheet,
Neither air mixing nor emboss removal was observed, and the design was high and the embossed sheet was suitable.

Example 2 An embossed sheet was manufactured under the same conditions as in Example 1 except that the line speed of the embossed sheet manufacturing apparatus was increased to 10 m / min, and the thickness of the embossed sheet was changed to 0.15 mmt.
Poor adhesion and air mixing were not observed in the obtained laminated sheet. Neither air mixing nor emboss loss was observed in the obtained embossed sheet, and the embossed sheet had high design properties and was suitable as an embossed sheet.

Example 3 Polypropylene-based embossing was carried out under the same conditions as in Example 1 except that the polypropylene resin was changed to low-density polyethylene (trade name: Petrocene 360, manufactured by Tosoh Corporation) and the temperature of the T-die outlet resin was changed to 205 ° C. A sheet was manufactured. Poor adhesion and air mixing were not observed in the obtained laminated sheet. The obtained embossed sheet is mixed with air,
Neither of the embossing was observed, and the design was high and the embossed sheet was suitable.

Example 4 A polypropylene embossed sheet was produced under the same conditions as in Example 1 except that a woven fabric made of a commercially available composite fiber having a width of 50 cm and consisting of 40% by weight of polyester fiber and 60% by weight of cotton yarn was used as the woven fabric. did. Poor adhesion and air mixing were not observed in the obtained laminated sheet. In addition, the resulting embossed sheet did not show any of air mixing and emboss removal, and had high designability and was suitable as an embossed sheet.

Example 5 A polypropylene-based embossed sheet was produced under the same conditions as in Example 4, except that the woven fabric was unwound from both sides of the melted polypropylene resin sheet, and the embossed pattern was transferred to both sides of the sheet. Adhesion failure and air mixing were not observed on any surface of the obtained laminated sheet. In addition, the resulting embossed sheet did not show any of air mixing or embossing loss on any surface, and had high designability and was suitable as an embossed sheet.

Example 6 The position of the pressing roll 4 was adjusted so that the pressing force between the molten polypropylene resin sheet and the woven fabric was 5 MPa, and the pressing length was 1.
A polypropylene-based embossed sheet was manufactured under the same conditions as in Example 4 except that the thickness was set to 00 mm. Poor adhesion and air mixing were not observed in the obtained laminated sheet. In addition, the resulting embossed sheet did not show any of air mixing and emboss removal, and had high designability and was suitable as an embossed sheet.

COMPARATIVE EXAMPLE The position of the pressing roll 4 in FIG. 1 was adjusted so that the pressing length between the molten polypropylene resin sheet and the woven fabric was 0 mm,
That is, a polypropylene-based embossed sheet was manufactured under the same conditions as in Example 1, except that the melted polypropylene resin sheet and the woven fabric were pressed only at the contact point between the forming rolls 3 and 3 '. Air mixing was observed in the obtained laminated sheet. Further, in the obtained embossed sheet, a lot of air mixing and embossing loss caused by air mixing were observed.

[0030]

According to the method using the embossing roll, the resin adheres to the embossing roll by continuous operation, and the design property is impaired. For this reason, the basic unit deteriorates due to removal of the attached resin and the like. However, according to the present invention, since emboss transfer is performed using a woven fabric, continuous operation can be performed. Therefore, the basic unit is improved, and an inexpensive embossed sheet can be obtained. Further, according to the present invention, since the emboss transfer to the sheet surface is performed in an arc shape, the transferability is good, and it is possible to easily and stably obtain an embossed sheet having high designability. That is, according to the present invention, an embossed sheet having good transferability can be continuously, easily, inexpensively and stably manufactured.

[0031]

[Table 1] Examples

[Brief description of the drawings]

FIG. 1 shows an example of the manufacturing apparatus of the present invention.

FIG. 2 shows an example of the manufacturing apparatus of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 T-die extrusion apparatus 2 Woven fabric feeding apparatus 3 Forming roll 3 'Forming roll 4 Compression roll 5 Metal endless belt 6 Peeling roll 7 Annealing roll 8 Thermoplastic resin sheet 9 Woven cloth 10 Embossed sheet

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 4F207 AA11 AF01 AG01 AG26 AR02 KA01 KA17 KK74 KK88 KL84 KL86 KM16 KW42 4F209 AA03 AA13 AA15 AF01 AG01 AG05 AJ08 PA08 PB02 PC05 PG12 PN06 PQ09

Claims (2)

[Claims] 1. A woven fabric is pressed on one or both sides of a sheet of thermoplastic resin extruded in a molten state from a T-die in an arc shape between a forming roll and a metal endless belt.
A method for producing an embossed sheet, comprising peeling a woven fabric from a thermoplastic resin sheet. 2. 5MP between a forming roll and a metal endless belt.
The embossed sheet manufacturing method according to claim 1, wherein the embossed sheet is formed by pressing at least 100 mm in a circular arc shape with a pressing force of at least a in a traveling direction of the sheet.