JPH0441642B2 - - Google Patents

Description

[Detailed description of the invention]

TECHNICAL FIELD The present invention relates to a method for producing a thermoplastic resin laminated film or sheet. More specifically, the present invention relates to a method for producing a thermoplastic resin laminate film or sheet having a two-layer structure with little variation in thickness and having a good appearance using a calender device. "Prior Art" Extrusion molding methods, laminate molding methods, and the like are conventionally known as methods for producing thermoplastic resin laminated films or sheets. However, these methods have the following drawbacks. That is, in the extrusion molding method, there is a problem of trouble in the laminated extrusion T-die section of the extruder. For example, when vinyl chloride resin is used as the thermoplastic resin material, the resin may burn, cleaning is troublesome, it is not easy to change the type, and the structure is complicated and expensive. In addition, in the laminate molding method, two or more types of films or sheets are first formed by calendering, extrusion, etc., and then laminated, which lengthens the process and increases production costs. In the laminating method using an adhesive, the solvent in the adhesive used volatilizes into the atmosphere, resulting in problems such as contaminating the working environment. Furthermore, in the case of films or sheets with a large elongation, it is difficult to apply the adhesive uniformly, and bubbles, wrinkles, etc. are likely to occur in the product. In addition, when laminating films or sheets made of thermoplastic resin materials with a low softening point, processing is difficult due to thermal shrinkage when the solvent in the adhesive is evaporated with hot air. Thermal adhesive lamination also has the disadvantage of requiring more heat sources because the films or sheets to be laminated must be reheated. "Problems to be Solved by the Invention" As a result of intensive studies aimed at providing a method that solves the above-mentioned problems in processing laminated films or sheets, the inventors of the present invention have developed a calendering device consisting of a plurality of rolling rolls. The inventors discovered a method for laminating thermoplastic resin laminated films or sheets in one fell swoop, and arrived at the present invention. "Means for Solving the Problems" Accordingly, the present invention provides a method for producing a thermoplastic resin material (A) in a molten state when producing a thermoplastic resin laminated film or sheet using a calender device consisting of a plurality of rolling rolls. is supplied to the rolling roll group and rolled to form a film or sheet flow,
A molten thermoplastic resin material (B), which is different from the thermoplastic resin material (A), is placed in the final nip formed by the pair of rolling rolls using a round bar-shaped die in the axial direction of the rolling rolls. The thermoplastic resin material (B) is supplied and laminated by an extruder that moves reciprocally along the same axis, and at this time, the moving speed of the extruder is controlled to be equal to or higher than the circumferential speed of the final rolling roll, and the supply amount of the thermoplastic resin material (B) is The gist of the present invention is to provide a method for manufacturing a thermoplastic resin laminated film or sheet, which is characterized in that the method is controlled based on the detection result of the average thickness of the thermoplastic resin laminated film or sheet wound from a calender device. The present invention will be explained in detail below. In the method of the present invention, the thermoplastic resin material used to process the laminated film or sheet is generally a polymer known to be calenderable or extrudable. Auxiliary agents such as lubricants, colorants, stabilizers, plasticizers, etc. can be added to these polymers. Examples of polymers include polyolefins such as polyethylene, polypropylene, polybutene 1, poly-4-methylpentene 1, polyisobutylene and copolymers thereof, polybutadiene, polyisoprene, polychloroprene, polycyanoprene and copolymers thereof. Polydienes such as copolymers with styrene and/or acrylonitrile, vinyl polymers such as polystyrene, polyalpha-methylstyrene, polyvinyl chloride, polyvinyl acetate and copolymers thereof, polyacrylics. Acids and polymethacrylic acids, esters and salts thereof, polyformals, polyalkylene oxides and copolymers thereof, polyarylethers such as polyphenylene oxide, polyvinylidene chloride and copolymers thereof, and acrylonitrile and styrene. and most addition polymers, such as copolymers of acrylonitrile and vinyl chloride. In addition, ethylene cellulose, cellulose acetate,
Also included are thermoplastic cellulosic materials such as cellulose butyrate, hydroxypropylcellulose, and the like. Other examples include standard condensation polymers, e.g.
polyesters such as polyethylene terephthalate and polyethylene isophthalate, polyamides such as poly-ε-caprolactam, polyhexamethylene adipamide and polyhexamethylene sebacinamide, bisphenol A polycarbonates,
Polysulfone and fiber-forming polymers made from hexamethylene diisocyanate and tetramethylene glycol, and diphenylmethane-p.
Included are thermoplastic polyurethanes such as elastomeric polymers made from p'-diisocyanate, adipic acid and butanediol-1.4. In the method of the present invention, a thermoplastic resin material (A) supplied to a calender device consisting of a plurality of rolling rolls is
The film or sheet is rolled at multiple upstream roll nips to form a film or sheet, which is flowed along the roll surface, and then kneaded by an extruder installed near the calender at the final nip of the rolling rolls of the calender. Another molten thermoplastic resin material (B) is supplied, and both materials are laminated to obtain the desired laminated film or sheet. Here, the thermoplastic resin materials (A) and (B) are both selected from the polymers exemplified above, and among them, vinyl chloride resin is the most preferred. Note that thermoplastic resin material (B) is "different" from thermoplastic resin material (A) if the types of polymers are different, of course.
Even if the polymers are the same, their degree of polymerization and molecular weight are different, and even if their degree of polymerization and molecular weight are the same, the types of resin additives such as lubricants, colorants, plasticizers, etc.
The meaning should be understood to include cases where the amounts are different and the melt viscosities are different. In the method of the present invention, the thermoplastic resin material (B) needs to have a lower melt viscosity than the thermoplastic resin material (A). That is, the thermoplastic resin material (B) is supplied to the final nip of the rolling roll group in the calender device, and the thermoplastic resin material (B) is laminated on the flow of the film or sheet made of the thermoplastic resin material (A). When the melt viscosity is higher than that of the thermoplastic resin material (A), it will bite into the film or sheet 10, and in extreme cases, it will break through and protrude to the side opposite to the laminated surface, impairing the appearance. No superior laminated film or sheet is formed. Therefore, when forming a laminated film or sheet from a thermoplastic resin material (A) and a thermoplastic resin material (B) containing the same kind of polymers, especially a vinyl chloride resin, the thermoplastic resin material (B) Thermoplastic resin materials can be improved by using vinyl chloride resins with a low degree of polymerization, by using resins with a large amount of plasticizer, or by increasing the melting temperature when being fed to the final nip of the rolling rolls. A material with a lower melt viscosity than (A) is selected. As a calender device equipped with a plurality of rolling rolls to which the method of the present invention is applied, for example, an inverted L-shaped 4
Main roll, L-shaped 4 rolls, Z-shaped 4 rolls, inclined Z-shaped 4 rolls, I-shaped 4 rolls, camel bag-type 4 rolls, I-shaped 3 rolls, reverse L-shaped 3 rolls, Kuno Examples of conventionally known types include a three-roll shape, a five-roll inverted L shape, a five-roll shape, and a five-roll L shape. The calendar device to which the method of the present invention is applied includes:
In order to supply the thermoplastic resin (B) between the final nips of the rolling rolls, an extruder equipped with a round-rod-shaped die at the tip is located near the calender device and can reciprocate in the width direction along the axis of the rolls. attached to. This extruder may be either a single screw extruder or a twin screw extruder. The round bar type die that is attached to the tip of the extruder is inexpensive, easy to clean, there is no place for molten resin to accumulate inside the die, and the resin does not burn, and the resin type It is superior to conventional T-dies in terms of ease of switching, low extrusion resistance at the die, and quick response to changes in the amount of resin extruded. FIG. 1 is a schematic cross-sectional view of an example of an inverted L-shaped calendar device to which the method of the present invention is applied, and FIG. 2 is a perspective view thereof. In the figure, 1, 2, 3, 4 are rolling rolls, 5
This is an extruder equipped with a round rod die 7 at the tip, which is provided so as to be able to reciprocate along the length direction of the roll on a rail 6 of a frame parallel to the axis. 8 is a first bank formed by supplying the molten thermoplastic resin material (A), 9 is a second bank, and 10 is a bank formed along the rolling roll surface through the first bank and the second bank 9. A film or sheet made of thermoplastic resin material (A). 11 is a third bank formed by the molten thermoplastic resin material (B) supplied from the extruder to the final nip formed by the rolling rolls 3 and 4; 12 is the thermoplastic resin material (A);
A thermoplastic resin material (B) is laminated onto a film or sheet 10 made of the above, and the resultant film or sheet is wound up as a product. In the above, the extruder 5 is configured such that the thermoplastic resin material (B) to be extruded is directly above the final nip formed by the rolling rolls 3, 4 or, for example, as shown in the enlarged cross-sectional view of FIG. Of the rolls 3 and 4, on the surface of the roll 4 adjacent to the roll 3 on which the film or sheet 10 made of thermoplastic resin material (A) is being transported, within a range of 90° from the nip (represented by θ), especially 45 Preferably, it is arranged at an angle such that a range of .degree. (denoted by _{.theta..sub.a} ) is provided. With this arrangement, the thermoplastic resin material (B) extruded from the round-rod-shaped die 7 of the extruder 5
It has the advantage that the temperature drop after extrusion can be suppressed to a minimum. In addition, the extruder 5 units are:
It is preferable to have a detachable structure for adjusting the vertical position of the die 7, changing the mounting angle, and changing the product type. An embodiment of the method of the present invention will be explained based on FIGS. 1 and 2. First, the thermoplastic resin material (A) that will become the first layer of the laminated film or sheet is prepared using a Henschel mixer or a ribbon blender. The mixture is mixed in a mixer (not shown), and then kneaded and melted in a kneader (not shown) such as a Banbury mixer or a kneader. Next, a swinging conveyor (not shown)
is supplied to the nip between the rolling rolls 1 and 2 where the first bank 8 is formed, and the rolling rolls 2 and 3 are
It is rolled into a film or sheet 10 through a nip formed by a second bank 9 in between. Then, a thermoplastic resin material (B) which becomes the second layer of the laminated film or sheet is supplied to the flow of the film or sheet 10 at the final nip between the rolling rolls 3 and 4 and laminated thereon. The thermoplastic resin material (B) is mixed in a mixer (not shown) such as a Henschel mixer or a ribbon blender, and then inserted into the extruder 5 and passed through a round bar die 7 attached to the tip of the extruder 5. Supplied by extrusion. During the extrusion operation, the extruder 5 reciprocates on the rail 6 in parallel with the axial direction of the rolling rolls, and transfers the thermoplastic resin material (B) in the width direction to the final nip between the rolling rolls 3 and 4. is extruded so that it is evenly distributed. The above thermoplastic resin material (B) is extruded, and the thermoplastic resin material flows through this and the upstream bank.
When laminating the film or sheet 10 made of (A), it is preferable that the laminated film or sheet has a good appearance with little variation in thickness. For this purpose, the film or sheet 10 is sufficiently rolled between the rolling rolls 2, 3,
It is preferable to adjust the spacing between the rolling rolls so that the thickness is no more than the final nip spacing formed in step 4, and that no rolling is performed between these nips. The amount of extrusion from the extruder 5 is preferably adjusted so that the third bank 11 formed at the final nip between the rolling rolls 3 and 4 is made of only the thermoplastic resin material (B). The third bank 11 formed at the final nip between the rolling rolls 3, 4 has a diameter in the range of 1.5 to 50 times, preferably in the range of 2 to 20 times, the thickness of the film or sheet 10 passing through this nip. It is best to adjust it to If the diameter of the third bank 11 is outside this range, a laminated film or sheet with stable thickness and excellent quality cannot be obtained. As a method of adjusting the amount of thermoplastic resin material (B) supplied to the calender device, for example, the thickness of the laminated film or sheet 12 flowing in the winding direction after passing through the final nip formed by the rolling rolls 3 and 4 can be adjusted. is detected using a known measuring device (beta wire thickness gauge) on one of the rolling rolls 4 or until it is wound up after leaving the rolling roll 4, and the detection result is sent as an electrical signal. The number of rotations of the extrusion screw drive motor of the extruder 5 is controlled in accordance with a command received from a controller (not shown) to automatically adjust the extrusion supply amount. The extruder 5, which has the function of extruding and supplying the thermoplastic resin material (B) to the nip formed by the final rolling rolls 3 and 4, runs parallel to the axial direction of the rolling roll in the longitudinal direction of the rolling roll. The moving speed is equal to or higher than the circumferential speed of the final rolling rolls 3 and 4 to which the thermoplastic resin material (B) is supplied. The moving speed is 3 pairs of rolling rolls,
If the circumferential speed is below 4, the extruded thermoplastic resin material (B) will be caught in the nip without being rolled evenly across the width of the roll, forming a uniformly laminated film or sheet. Not done. Further, the extrusion supply speed (V) of the thermoplastic resin material (B) extruded and supplied from the extruder 5 to the pairs of rolling rolls 3 and 4 is controlled by the third bank having a size within a certain range in the nip between the rolls as described above. 11 is formed, and if the peripheral speed of the final rolling rolls 3 and 4 is V ₁ and the reciprocating speed of the extruder is V ₂ , then V≦√ ² ₁
Preferably, V ² ≦V≦ so that the relationship of +V _{2 2} is satisfied.
Adjustments are made so that the relationship √ ² ₁ + ² ₂ holds. For this purpose, the round bar die attached to the tip of the extruder 5 is selected to have a diameter that satisfies the above requirements. If the above requirements are not met,
The supplied thermoplastic resin material (B) forms a loop at an undetermined position on the roll, and the thickness increases at that portion, making it impossible to obtain a high-quality laminated film or sheet with excellent commercial value. "Effects of the Invention" As described above, the method of the present invention uses a calendar device equipped with a plurality of rolling rolls, and rolls different types of thermoplastic resin materials between the rolls into a film or sheet. This method involves direct lamination to obtain a laminated film or sheet, and has the following various advantages, and its industrial utility value is great. (1) The equipment used is simpler than the conventional method. (2) Fewer steps than conventional methods. (3) It is easy to clean the equipment, therefore it is easy to switch production to a different type of product, and the loss time for equipment cleaning is reduced. (4) Production costs are reduced. (5) Normal calendar equipment can be shared, reducing equipment costs. "Examples" The present invention will be described in detail based on Examples below, but the present invention is not limited to the following examples unless the gist thereof is exceeded. Example 1 Vinyl chloride resin 100PHR (Per
Hundred Resin), DOP50PHR, Ba/Zn liquid stabilizer 2PHR, lubricant 1PHR and white pigment ( _TiO2 :
The soft vinyl chloride resin material (A) containing 3PHR (titanium oxide) was mixed using a super mixer manufactured by Kawada Manufacturing Co., Ltd., and kneaded using a Banbury mixer. This is put into a small mill, the temperature is adjusted and it is made into a molten product, and then the top nip (top bank or first bank) of an inverted L-shaped calendar consisting of four rolls with a diameter of 10 inches and a length of 25 inches as shown in Figure 1 is produced. 8) was fed in a constant quantity using an oscillating conveyor to form a flow of film made of the soft vinyl chloride resin material (A). On the other hand, vinyl chloride resin with polymerization degree = 1300
100PHR, DOP50PHR, Ba/Zn liquid stabilizer
A soft vinyl chloride resin material (B) containing 2 PHR, 1 PHR lubricant, and 1 PHR red pigment was kneaded in the same manner as the above soft vinyl chloride resin material (A), and
The film is fed by an extruder to the final nip formed by step 4, and the film is laminated on the flow of the film, and the thickness is
A laminated film of 0.2 m/m was obtained. The extruder used (L/D = 28) was a single-axis moving extruder that moved back and forth on rails 6 parallel to the axis of the roll, and the thickness of the laminated film being wound up from the calender device was detected by a detector. Depending on the thickness of the laminated film,
The extrusion amount was adjusted by controlling the moving speed and the screw rotation speed. The results are shown in Table 1.

【table】

[Table] Uniformity Example 2 A soft vinyl chloride resin material (A) and a soft vinyl chloride resin material (B) having the same composition as in Example 1 were used in the same equipment as used in Example 1. Laminated under the same conditions as Example 1 except that the extrusion temperature of the vinyl chloride resin material (B) was changed to 200°C,
A laminated film of 0.2 m/m was obtained. The results are shown in Table 2.

[Table] Comparative Examples 1 to 2 A soft vinyl chloride resin material (A) and a soft vinyl chloride resin material (B) having the same composition as in Example 1 were used to produce soft vinyl chloride resin material using the same equipment as in Example 1. resin material
The reciprocating speed of the extruder that supplies (B) is 2m/mi.
(Comparative Example 1) and 7m/mi (Comparative Example 2) were laminated under the same conditions as Example 1, and 0.2m/mi
A laminated film was obtained. These results are shown in Table 3.

[Table] As is clear from the results of Examples 1 and 2 and Comparative Examples 1 and 2 above, the reciprocating speed of the extruder that supplies the thermoplastic resin material (B) to the final rolling roll is It can be seen that when the speed is higher than the circumferential speed and lower than the supply speed of the resin material (B), a laminated film of better quality can be obtained than when laminated using a method other than this condition.

[Brief explanation of drawings]

FIG. 1 is a schematic side view showing an example of a calender device applied to the method of the present invention, FIG. 2 is a perspective view of the same, and FIG. 3 is an explanatory side view showing the supply position of the thermoplastic resin material (B). FIG. 4 is an enlarged sectional view of an example of a laminated film or sheet obtained by the method of the present invention. 1, 2, 3, 4... Roll, 5... Extruder, 6... Rail, 7... Round bar die, 8... First
Bank, 9...Second bank, 11...Third bank, 12...Laminated film or sheet.

Claims (1)

[Scope of Claims] 1. When producing a thermoplastic resin laminated film or sheet using a calender device consisting of a plurality of rolling rolls, a molten thermoplastic resin material (A)
is supplied to the group of rolling rolls and rolled to form a film or sheet flow, and a molten material different from the thermoplastic resin material (A) is supplied to the final nip formed by the pair of rolling rolls. Thermoplastic resin material (B)
are supplied and laminated by an extruder equipped with a round bar-shaped die that moves reciprocally along the axial direction of the rolling rolls, and at this time, the moving speed of this extruder is set to be equal to or equal to the circumferential speed of the final pair of rolling rolls. In addition to controlling the amount of thermoplastic resin material (B) supplied based on the detection result of the average thickness of the thermoplastic resin laminated film or sheet wound from the calender device. A method for producing a plastic resin laminated film or sheet. 2 The melt viscosity of the molten thermoplastic resin material (B) is
The method for producing a thermoplastic resin laminated film or sheet according to claim 1, characterized in that the thickness is made smaller than that of the molten thermoplastic resin material (A).