JP2001129845A - Apparatus and method for producing thermoplastic resin sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an apparatus and a method for producing a thermoplastic resin sheet prevented from neck-in, uniform in thickness and having good surface properties with good productivity by calender processing. SOLUTION: An apparatus for producing a thermoplastic resin sheet by calender processing is constituted of a three-roll group consisting of first, second and third rolls arranged horizontally in series so as to approach each other and a two-roll group consisting of the fourth roll positioned just under the third roll in close vicinity thereto and the fifth roll arranged horizontally in series in close vicinity to the fourth roll. This apparatus is used to subject a thermoplastic resin material to calender processing to produce the thermoplastic resin sheet.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for producing a thermoplastic resin sheet and a method for producing the sheet using the apparatus. More specifically, the present invention prevents neck-in,
An apparatus for producing a thermoplastic resin sheet having a uniform thickness and good surface properties, particularly a thermoplastic resin sheet having a thickness of about 0.02 to 1.0 mm by calendering with good productivity, and using this apparatus, The present invention relates to a method for easily producing a thermoplastic resin sheet having good productivity.

[0002]

2. Description of the Related Art As a method for producing a thermoplastic resin sheet, a casting method (solution casting method), an extrusion method (melt extrusion method), a calendering method and the like are known. Among them, the calendering method is a method of rolling a thermoplastic resin material between two or more rolls to form a sheet, and is particularly awarded in the production of a soft vinyl chloride resin sheet. As the arrangement of the calender rolls in the calendering method, an upright type three roll, an upright type four roll, an L type four roll, an inverted L type four roll, a Z type four roll and the like are generally used. In such calendering, in recent years, further improvement in quality and productivity (high-speed molding) for sheet products has been required. In order to improve the quality of the obtained sheet, it is important to suppress the formation of neck-in and gear marks, to improve the surface properties, and to make the thickness uniform.
In addition, the upright type roll and the L-type roll are 3
Since five to five rolls are arranged, the gantry of the calendar roll group becomes large-scale, and the calendering work also needs to be performed while the operator moves up and down. However, it is not always satisfactory in terms of productivity, productivity, and the like.

[0003]

SUMMARY OF THE INVENTION Under such circumstances, the present invention prevents a neck-in, and provides a thermoplastic resin sheet having a uniform thickness and good surface properties, particularly a thickness of 0.02.
An apparatus for manufacturing a thermoplastic resin sheet having a thickness of about 1.0 mm with high productivity by calendering, and using this apparatus,
An object of the present invention is to provide a method for easily manufacturing a thermoplastic resin sheet having the above-mentioned properties with good productivity.

[0004]

Means for Solving the Problems The inventor of the present invention has conducted intensive studies in order to achieve the above object, and as a result, has found that a specific configuration
A device composed of a group of rolls can be adapted to the purpose as a calendering device, and by calendering a thermoplastic resin material using this device, a desired thermoplastic resin sheet of good quality can be obtained. Was found to be easily obtained with good productivity, and based on this finding, the present invention was completed. That is, the present invention
(1) Three roll groups each consisting of a first roll, a second roll, and a third roll, which are respectively disposed in close proximity to a horizontal series, and a fourth roll, which is positioned vertically below and close to the third roll, A calendering apparatus comprising two roll groups consisting of a fifth roll disposed adjacent to each other in a horizontal series with respect to this roll, wherein the position of the axis of the second roll is fixed, and The first roll and the third roll can move at least horizontally in the horizontal direction, and the fourth roll and the fifth roll have a mechanism that can move in the horizontal direction and the vertical direction, respectively. A thermoplastic resin sheet manufacturing apparatus, wherein the roll is provided with a temperature adjustment mechanism and a rotation speed adjustment mechanism,
(2) The thermoplastic resin sheet manufacturing apparatus according to (1), wherein the five rolls have substantially the same diameter and length, respectively. (3) The fifth roll is located at the center in the length direction. 3. The apparatus for manufacturing a thermoplastic resin sheet according to item 1 or 2, further comprising a mechanism that moves in a vertical direction with the horizontal central axis as a fixed axis and that can have an inclined structure, (4) item 1, item 2, or 4. A method for producing a thermoplastic resin sheet, wherein the thermoplastic resin material is calendered using the production apparatus according to claim 3. (5) The center of the end face of the fifth roll is the longitudinal center of the fourth roll. 2% of the roll length perpendicular to the axis
In order to move at the following ratio, the fifth roll is inclined with the horizontal central axis at the center in the length direction as a fixed axis,
The method for producing a thermoplastic resin sheet according to claim 4, wherein calendering is performed, (6) the thickness of the sheet fed by the fourth roll is 0.2 to 1.0 mm, and the thickness of the sheet fed by the fifth roll. (4) The method for producing a thermoplastic resin sheet according to (4) or (5), wherein the rotational speed of the fifth roll is 1.0 to 1.0 of the rotational speed of the fourth roll. 7. The method for producing a thermoplastic resin sheet according to item 6, wherein the ratio is 10 times.

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION The thermoplastic resin sheet manufacturing apparatus of the present invention comprises a three-roll group consisting of a first roll, a second roll and a third roll, which are disposed adjacent to each other in a horizontal series. It comprises a fourth roll positioned vertically below and close to the three rolls, and two roll groups consisting of a fifth roll disposed horizontally adjacent to this roll. And, outside the fifth roll, a pair of touch rolls are usually arranged close to each other, but in some cases, a pressure roll for laminating another sheet by heat fusion is used instead of the touch roll. They may be arranged. In this device, the position of the axis of the second roll is fixed, and the axes of the first and third rolls on the left and right sides thereof can move at least in the horizontal direction, and the axes of the fourth roll and the fifth roll are Each of the rolls is provided with a mechanism capable of moving in the horizontal direction and the vertical direction, and each roll is provided with a temperature adjustment mechanism and a rotation speed adjustment mechanism. In the present invention, the five rolls generally have substantially the same diameter and length, respectively. The diameter and length of the roll are appropriately selected depending on the width and the production amount of the sheet, but the diameter of the roll is generally about 500 to 900 mm,
The length of the roll is generally about 1500-2700 mm. Furthermore, in the device of the present invention, the fifth roll
It is preferable to provide a mechanism that can move in the vertical direction with the horizontal central axis at the central portion in the length direction as a fixed axis and take an inclined structure. This means that by slightly crossing the fifth roll with respect to the fourth roll in the vertical direction, the tensile stress applied to the sheet sent from the fourth roll is finely adjusted, the thickness of the sheet is homogenized, and the This is for improving the surface properties. Next, the device of the present invention will be described with reference to the accompanying drawings. FIG. 1 is a side view of an example of a calender roll group in the thermoplastic resin sheet manufacturing apparatus of the present invention. As shown in FIG. 1, this calender roll group includes three rolls of a first roll 1, a second roll 2, and a third roll 3 which are arranged in a horizontal series and close to each other. The fourth roll 4 is disposed close to and vertically below the fifth roll 5, and the fifth roll 5 is disposed adjacent to the fourth roll 4 in a horizontal series. , A pair of touch rolls 6 are arranged close to each other. The position of the axis of the second roll 2 is fixed, and a mechanism that allows the left and right axes of the first roll 1 and the third roll 3 to move horizontally and, if necessary, a mechanism that can move up and down is provided. ing. Further, a mechanism is provided in which the axes of the fourth roll 4 and the fifth roll 5 can move in the horizontal direction and the vertical direction, respectively, and a mechanism in which the touch roll 6 can be interlocked with the fifth roll 5 is provided. ing. First roll 1, second roll 2, third roll 3, fourth roll 4, and fifth roll 5
Usually have substantially the same diameter and length, respectively, and each roll has a temperature regulating mechanism (cooling or heating mechanism by introducing a fluid) for maintaining the roll surface at a predetermined temperature, and A rotation speed adjusting mechanism is provided.

Further, the fifth roll 5 can move in the vertical direction with the horizontal central axis at the center in the longitudinal direction as a fixed axis, and can have an inclined structure, that is, it can cross the fourth roll 4. A mechanism is provided. After the melt or the strip of the thermoplastic resin material is supplied to the bank 7 between the first roll 1 and the second roll 2 rotating in the direction of the arrow, the sheet is formed into a sheet. The third roll 3, the fourth roll 4, and the fifth roll 5 rotating in order, and finally, via the touch roll 6,
It is sent out as a product sheet 8. Next, a method for producing the thermoplastic resin sheet of the present invention will be described. The method for producing a thermoplastic resin sheet of the present invention is a method for producing a sheet by calendering a thermoplastic resin material using the above-described production apparatus. The method of supplying the thermoplastic resin material to the bank 7 between the first roll 1 and the second roll 2 is not particularly limited, and can be appropriately selected according to the type of the thermoplastic resin used. For example, if the resin is stable without being thermally decomposed even at a temperature higher by about 30 to 60 ° C. than the melting temperature, such as a polyolefin resin, the melting of the thermoplastic resin material extruded from the slit of the die of the extruder. An object is supplied to the bank 7. On the other hand, in the case of a resin having a low thermal decomposition temperature, such as a vinyl chloride resin, the thermoplastic resin material kneaded material is formed into a plate shape using a mixing roll or the like, and the belt-like material is supplied to the bank 7 by a conveyor or the like.
In this way, the sheet rolled by the first roll 1 and the second roll 2 passes through the third roll 3, the fourth roll 4, the fifth roll 5, and the touch roll 6, and becomes a product sheet. As for the thickness of the sheet, the thickness of the sheet fed by the fourth roll is usually in the range of 0.2 to 1.0 mm, and the thickness of the sheet fed by the fifth roll is usually 0.02.
It is in the range of 1.0 mm. Therefore, the thickness of the sheet sent out by the second roll and the third roll is usually 0.2 mm or more. The thickness of the sheet fed by the second roll, the third roll and the fourth roll is 0.2 m.
If it is less than m, a gear mark is likely to be formed on the sheet surface, and the resulting product sheet may have poor surface properties.
The thickness of the product sheet is usually 0.02 as described above.
Since it is １1.0 mm, the sheet will be further stretched, if desired, on the fifth roll. The optional stretching is performed by increasing the rotation speed of the fifth roll to be higher than the rotation speed of the fourth roll.
In the present invention, the rotation speed of the fifth roll is preferably in the range of 1.0 to 10 times the rotation speed of the fourth roll. The rotation speed of the fourth roll is usually 3 to 60 m / min,
Preferably 5 to 50 m / min, more preferably 8 to 40 m
/ Min. In order to stretch the sheet fed by the fourth roll with the fifth roll, the surface temperature of the fourth roll and the fifth roll is preferably the softening temperature of the sheet or a temperature slightly higher than the softening temperature.

When a thermoplastic resin having good thermal stability is used, the melt of the thermoplastic resin material supplied from the die of the extruder to the bank between the first roll and the second roll constitutes the material. 30 to 60 ° C higher than the melting point of the thermoplastic resin
It is preferable to have a high temperature. For example, when the thermoplastic resin is a polypropylene resin, it is usually 200 to 230.
It is in the range of ° C. If the thermoplastic resin is such a polypropylene resin, the first roll, the second roll, the third roll, the fourth roll and the roll surface temperature of the fifth roll,
Generally, it is preferable to adjust the temperature in the range of 95 to 140 ° C. On the other hand, when the thermoplastic resin is a vinyl chloride resin, the roll surface temperature of the first roll, the second roll, the third roll, the fourth roll, and the fifth roll is generally 140 to 180.
It is preferable to adjust the temperature in the range of ° C. As for the rotation speed of the first roll to the fourth roll, when the rotation speed of the first roll is 1, the second roll is about 1.05, and the third roll is 1.
The first roll and the fourth roll are about 1.15, and the rotation speed of the fourth roll is usually 3 to 60 m / min, as described above,
Preferably 5 to 50 m / min, more preferably 8 to 40 m
/ Min. The gap between the first roll and the second roll, the second roll and the third roll, and the gap between the third roll and the fourth roll are set such that the thickness of the sheet fed by the fourth roll becomes 0.2 to 1.0 mm. The selection may be made in consideration of the rotation speed of each roll. The fifth roll is placed as close as possible to the fourth roll in order to prevent neck-in, and as described above, the rotation speed of the fourth roll is 1.0-1.
It is preferable to rotate in a range of 0 times. In the present invention, in order to finely adjust the tensile stress applied to the sheet sent from the fourth roll, to homogenize the thickness of the sheet, and to improve the surface properties thereof, the end face of the fifth roll. The horizontal center axis of the fifth roll is fixed to the center in the length direction so that the center moves vertically at a rate of 2% or less of the roll length with respect to the center axis in the length direction of the fourth roll. The calendering can be performed in a state of being inclined, that is, in a state of slightly crossing the fourth roll. The thus obtained thickness of 0.02
The thermoplastic resin sheet having a thickness of about 1.0 mm is supplied to a cooling step and cooled, and then wound up by a take-up roll or cut by a cutting machine. The thermoplastic resin to which the method of the present invention is applied may be any resin that can be calendered, and is not particularly limited, and may include various resins. Representative examples of such resins include:
Examples thereof include a vinyl chloride resin, a polyolefin resin, a polyester resin, and an acrylic resin. Of these, a polyolefin resin is preferable. Here, the vinyl chloride resin has a number average polymerization degree of about 8
00 to about 2500, preferably about 1000 to about 1800
Of polyvinyl chloride or a copolymer mainly composed of vinyl chloride (eg, ethylene-vinyl chloride copolymer, vinyl acetate-vinyl chloride copolymer), or a copolymer mainly composed of polyvinyl chloride or vinyl chloride And other compatible resins (eg, polyester resin, acrylic resin, vinyl acetate resin, urethane resin, acrylonitrile-styrene-butadiene copolymer resin, partially saponified polyvinyl alcohol, etc.). it can.

[0008] The polyolefin resin is not particularly limited, for example, ethylene, propylene, butene-1,3
Α-olefin homopolymers such as -methylbutene-1, 3-methylpentene-1, 4-methylpentene-1, and the like, and copolymers thereof, or a copolymer thereof with another copolymerizable unsaturated monomer. And copolymers. Representative examples include high-density, medium-density, low-density polyethylene, linear low-density polyethylene, ultra-high-molecular-weight polyethylene, ethylene-vinyl acetate copolymer, polyethylene such as ethylene-ethyl acrylate copolymer, and propylene alone. Polypropylenes such as polymers, propylene-ethylene block copolymers and random copolymers, propylene-ethylene-diene compound copolymers, polybutene-1, poly-4-
Methylpentene-1 and the like can be mentioned, and among these, a crystalline polypropylene resin is preferable. As the crystalline polypropylene-based resin, for example, isotactic propylene homopolymer having crystallinity, ethylene-propylene random copolymer having a small content of ethylene units, a homo part composed of propylene homopolymer and a content of ethylene units A propylene block copolymer composed of a relatively large amount of an ethylene-propylene random copolymer and a homopolymer or copolymer in the propylene block copolymer. And a crystalline propylene-ethylene-α-olefin copolymer formed by copolymerizing an α-olefin such as the above. Examples of the polyester resin include polyethylene terephthalate and polyethylene naphthalate, and typical examples of the acrylic resin include polymethyl methacrylate. The thermoplastic resin material used in the method of the present invention may contain various additives, such as inorganic fillers, antioxidants, heat stabilizers, ultraviolet absorbers, and light additives, as required, in one or more of the thermoplastic resins. Stabilizers, plasticizers, flame retardants, flame retardant aids, lubricants, process oils, release agents, antistatic agents, colorants, etc. are blended and mixed with a tumbler blender, Henschel mixer, etc. or after mixing. It is prepared by melt-kneading and granulating using a screw extruder or a multi-screw extruder.

[0009]

EXAMPLES Next, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples. Example 1 (1) Preparation of thermoplastic resin material 40 parts by weight of homopolypropylene [weight average molecular weight: about 320,000, melt index (MI): 3.1 g / 10 minutes]
55 parts by weight of calcium carbonate powder having an average particle size of 1.0 μm,
After dry blending 5 parts by weight of titanium oxide powder and 0.2 parts by weight of a hindered phenolic antioxidant, the mixture was melt-kneaded with a biaxial kneader to prepare a pellet-shaped thermoplastic resin material. The melting point of the homopolypropylene was 165 ° C and the softening point was about 130 ° C. (2) Production of Sheet As a production apparatus, an apparatus having a group of calender rolls shown in FIG. 1 was used. Each of the first to fifth rolls has a diameter of 610 mm and a length of 1800 mm. Further, the roll surface temperature and the rotation speed of the first roll, the second roll, the third roll, the fourth roll, and the fifth roll were respectively set to 105 ° C. and 26 m / min; 110 ° C. and 27 m / min;
20 ° C., 29 m / min; 130 ° C., 30 m / min and 130
° C and 150 m / min. Further, the center of the end face of the fifth roll is moved by 20 mm in the vertical direction with respect to the longitudinal center axis of the fourth roll, so that the horizontal center axis at the central portion in the longitudinal direction of the fifth roll is used as a fixed axis. Tilted. The thermoplastic resin material obtained in the above (1) is charged into an extruder,
From the die slit, melt the material (temperature 210 ° C)
Was extruded and fed between a first roll and a second roll. The melt is formed into a sheet, fed from a second roll through a third roll and a fourth roll, and supplied to a fifth roll as a sheet having a thickness of about 0.5 mm. It was sent out as a 0.1 mm product sheet. This sheet was transferred to a cooling mechanism, cooled to near room temperature, and then wound up by a take-up roll to obtain a polypropylene sheet having a thickness of 0.1 mm and a width of 1600 mm. This sheet had no neck-in or gear mark, had good surface properties, and had a uniform thickness.

[0010]

By using the apparatus for producing a thermoplastic resin sheet of the present invention, neck-in is prevented, and a thermoplastic resin sheet having a uniform thickness and good surface properties, particularly, a thickness of 0.1 mm.
A thermoplastic resin sheet of about 02 to 1.0 mm can be manufactured with high productivity by calendering.

[Brief description of the drawings]

FIG. 1 is a side view of one example of a calender roll group in a thermoplastic resin sheet manufacturing apparatus of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 1st roll 2 2nd roll 3 3rd roll 4 4th roll 5 5th roll 6 Touch roll 7 Bank 8 Product sheet

Claims (7)

[Claims] A first roll, a second roll, and a third roll, each of which is disposed adjacent to each other in a horizontal series, and a fourth roll group, which is positioned vertically below the third roll, A roll processing apparatus comprising a roll and two rolls each including a fifth roll arranged in close proximity to the roll in a horizontal series, wherein the position of the axis of the second roll is fixed, and The axes of the left and right first roll and third roll can move at least in the horizontal direction,
The shaft of the fourth roll and the fifth roll is provided with a mechanism capable of moving in the horizontal direction and the vertical direction, respectively, and further, each roll is provided with a temperature control mechanism and a rotation speed control mechanism. Thermoplastic sheet production equipment. 2. The thermoplastic resin sheet manufacturing apparatus according to claim 1, wherein each of the five rolls has substantially the same diameter and length. 3. The thermoplastic resin sheet according to claim 1, wherein the fifth roll has a mechanism capable of moving in a vertical direction with a horizontal central axis at a central portion in the longitudinal direction as a fixed axis and having an inclined structure. Manufacturing equipment. 4. A method for producing a thermoplastic resin sheet, comprising calendering a thermoplastic resin material using the production apparatus according to claim 1. 5. The fifth roll is moved in the longitudinal direction such that the center of the end face of the fifth roll moves perpendicular to the longitudinal center axis of the fourth roll at a rate of 2% or less of the roll length. 5. The method for manufacturing a thermoplastic resin sheet according to claim 4, wherein calendering is performed by inclining the horizontal central axis at the center of the sheet with the fixed axis. 6. The sheet fed by the fourth roll has a thickness of 0.2 to 1.0 mm, and the sheet fed by the fifth roll has a thickness of 0.02 to 1.0 mm.
A method for producing the thermoplastic resin sheet according to the above. 7. The method for producing a thermoplastic resin sheet according to claim 6, wherein the rotation speed of the fifth roll is 1.0 to 10 times the rotation speed of the fourth roll.