KR20120120898A - Method for producing resin molded body - Google Patents

Abstract

PURPOSE: A molded resin article manufacturing method is provided to prevent the damage of a polymer filter by passing thermoplastic resin having MVR(melt volume flow rate) value within a dimensional range through a polymer filter successively. CONSTITUTION: A molded resin article manufacturing method is as follows. Thermoplastic resin is filtered by passing melted thermoplastic resin through a polymer filter(12). The thermoplastic resin has MVR value higher than a predetermined MVR value. The thermoplastic resin is molded after the filtering process.

Description

Manufacturing method of resin molding {METHOD FOR PRODUCING RESIN MOLDED BODY}

The present invention relates to a method for producing a resin molded article.

Resin films used for optical applications are widely used, for example, in liquid crystal cells, retardation films, diffusion films, brightness enhancement films and the like combined with optical discs and polarizing plates.

Patent Document 1? 4, the manufacturing method of a resin film is disclosed. Patent Document 1? In the manufacturing method of the resin film disclosed in 4, the extruder which heats and melts the resin material which is a pelletized thermoplastic resin, and extrudes the melted resin, the die which extrudes the resin of the molten state extruded from the extruder into a film form, and the die The resin film is manufactured using the resin film manufacturing long value provided with the some roll which sandwiches resin extruded from the film form from the inside.

Japanese Unexamined Patent Publication No. 2009-196327 Japanese Unexamined Patent Publication No. 2009-202382 Japanese Patent Application Laid-Open No. 64-72832 Japanese Patent Application Laid-Open No. 64-72833

However, Patent Document 1? In the manufacturing method of the resin film disclosed in 4, foreign substances, such as a gel, may contain in the obtained resin film, and it is a remarkable commodity value in the use which strictly examines external appearance quality, such as an optical protective film or sheet | seat, and a medical product. Is lowered.

As a method of removing a foreign material, the method of forming a polymer filter between an extruder and die | dye, and passing the resin extruded from an extruder through a polymer filter is considered. However, when the resin with high viscosity extruded from the extruder is passed at once, a problem arises that the polymer filter is broken. This problem is not only for producing a resin film, but also for the production of resin molded bodies (resin sheets, injection molded bodies, etc.) other than the resin film, which include a step of filtering the resin in the molten state extruded by an extruder with a polymer filter. It is a problem that occurs.

An object of the present invention is to provide a method for producing a resin molded body which can prevent breakage of the polymer filter when the resin molded body is passed through a polymer filter and the resin extruded from the extruder to remove foreign substances.

The present invention is a method of manufacturing a resin molded body made of a thermoplastic resin having a predetermined melt volume flow rate (MVR) value,

A filtration step of performing a filtration treatment by passing a molten thermoplastic resin extruded from an extruder through a polymer filter, wherein the thermoplastic resin having a melt volume flow rate value larger than the predetermined melt volume flow rate value is passed through the polymer filter. A filtration step of performing a filtration treatment after passing the thermoplastic resin having the predetermined melt volume flow rate value through the polymer filter;

It is a manufacturing method of the resin molded object characterized by including the shaping | molding process of shape | molding the thermoplastic resin after a filtration process.

In addition, the present invention, the filtration step,

3 to 3 for said predetermined melt volume flow rate value; A first filtration step of passing a thermoplastic resin having a melt volume flow rate value of five times through the polymer filter,

2 to the predetermined melt volume flow rate value; A second filtration step of passing the thermoplastic resin having a triple melt volume flow rate value through the polymer filter,

And a third filtration step of passing the thermoplastic resin having the predetermined melt volume flow rate value through the polymer filter.

Moreover, in this invention, the said predetermined | prescribed melt volume flow rate value is 10 cm <3> / 10min or more and 20 cm <3> / 10min or less,

In the first filtration step, a thermoplastic resin having a melt volume flow rate value of 60 cm 3/10 min or more and 80 cm 3/10 min or less is passed through the polymer filter,

In the second filtration step, a thermoplastic resin having a melt volume flow rate value of 30 cm 3/10 min or more and 50 cm 3/10 min or less is passed through the polymer filter.

In addition, the present invention is characterized in that the thermoplastic resin is a polycarbonate resin.

According to this invention, in the manufacturing method of a resin molded object, the resin molded object which consists of a thermoplastic resin which has a predetermined | prescribed melt volume flow rate value is manufactured. The manufacturing method of a resin molded object includes the filtration process of carrying out the filtration process by passing the thermoplastic resin of the molten state extruded from the extruder through a polymer filter, and the shaping process of shape | molding the thermoplastic resin after the filtration process. In the manufacturing method of such a resin molded object, in the said filtration process, after passing the thermoplastic resin which has a melt volume flow rate value larger than the said predetermined melt volume flow rate value through a polymer filter, the said predetermined melt volume flow rate value The thermoplastic resin which has an is passed through a polymer filter, and a filtration process is performed.

After passing through the polymer filter a thermoplastic resin having a melt volume flow rate value greater than the predetermined melt volume flow rate value, that is, a thermoplastic resin having a viscosity lower than that of the thermoplastic resin having the predetermined melt volume flow rate value, By passing the thermoplastic resin having a melt volume flow rate value of P through the polymer filter, breakage of the polymer filter caused by passing the thermoplastic resin with high viscosity at once can be prevented.

Moreover, according to this invention, it is preferable that a filtration process includes a 1st filtration process, a 2nd filtration process, and a 3rd filtration process. In the first filtration step, 3? Preferably, a thermoplastic resin having a melt volume flow rate value of five times is passed through the polymer filter. In a 2nd filtration process, it is 2-about the said predetermined | prescribed melt volume flow rate value. Preferably, a thermoplastic resin having a melt volume flow rate value of three times is passed through the polymer filter. In the third filtration step, it is preferable to pass the thermoplastic resin having the predetermined melt volume flow rate value through the polymer filter.

The third filtration step is a step of passing the thermoplastic resin having a high viscosity through the polymer filter. In the first filtration step and the second filtration step, the thermoplastic resin having a melt volume flow rate value within the numerical range is sequentially passed through the polymer filter, so that the thermoplastic resin having a high viscosity is passed through the polymer filter in the third filtration step. Even if it does so, damage to a polymer filter can be prevented reliably.

Moreover, according to this invention, it is preferable that the said predetermined | prescribed melt volume flow rate value is 10 cm <3> / 10min or more and 20 cm <3> / 10min or less. In a 1st filtration process, it is preferable to pass a thermoplastic resin whose melt volume flow rate value is 60 cm <3> / 10min or more and 80cm <3> / 10min or less through a polymer filter. In the second filtration step, it is preferable to pass a thermoplastic resin having a melt volume flow rate value of 30 cm 3/10 min or more and 50 cm 3/10 min or less through the polymer filter.

It is preferable that a 3rd filtration process is a process of passing a thermoplastic resin with a high viscosity with a melt volume flow rate value of 10 cm <3> / 10min or more and 20cm <3> / 10min or less, through a polymer filter. In the first filtration step and the second filtration step, the thermoplastic resin having a melt volume flow rate value within the numerical range is sequentially passed through the polymer filter, so that the thermoplastic resin having a high viscosity is passed through the polymer filter in the third filtration step. Even if it does so, damage to a polymer filter can be prevented reliably.

Moreover, according to this invention, a thermoplastic resin is a polycarbonate resin. In the manufacturing method of the resin molded object of this invention, the resin molded object which consists of polycarbonate resin can be manufactured, without damaging a polymer filter.

FIG. 1: is a figure which shows typically the structure of the resin film manufacturing apparatus 100 used by the manufacturing method of the resin molded object which is one Embodiment of this invention.
2 is a cross-sectional view schematically showing the configuration of the polymer filter 12.

The manufacturing method of the resin molded object of this invention manufactures the resin molded object which consists of a thermoplastic resin which has a predetermined melt volume flow rate (henceforth "MVR") value. As a resin molded object, the resin film obtained by shape | molding in a film form, the resin sheet obtained by shape | molding in a sheet form, the injection molded object obtained by injection molding, etc. are mentioned.

Here, the MVR value of the thermoplastic resin is a value measured under conditions of a predetermined temperature and load according to ISO 1133, and is an index of the shear rate of the thermoplastic resin. This MVR value has a correlation with the viscosity of a thermoplastic resin, and a viscosity becomes low as MVR value becomes large. In addition, the temperature and load at the time of measuring an MVR value are set suitably according to the kind of thermoplastic resin.

Examples of the thermoplastic resin that can be used in the present invention include rubber-reinforced styrene resins such as polystyrene, high impact polystyrene, medium impact polystyrene, styrene-acrylonitrile copolymer (SAN resin), acrylonitrile-butylacryl Lateral rubber-styrene copolymer (AAS resin), acrylonitrile-ethylenepropyl rubber-styrene copolymer (AES), acrylonitrile-polyethylene-styrene copolymer (ACS), ABS resin (e.g. acrylonitrile Styrene resins such as butadiene-styrene copolymer, acrylonitrile-butadiene-styrene-alphamethylstyrene copolymer, acrylonitrile-methyl methacrylate-butadiene-styrene copolymer), polymethyl methacrylate (PMMA) Olefin resins such as acrylic resins such as acrylic resin, low density polyethylene (LDPE), high density polyethylene (HDPE), and polypropylene (PP), polyvinyl chloride, Vinyl chloride-based resins such as polyvinylidene chloride, vinyl chloride-based copolymer resins such as ethylene-vinyl acetate copolymer, ethylene-vinyl chloride copolymer, polyethylene terephthalate (PETP, PET), polybutylene terephthalate (PBTP, PBT Polycarbonate resins such as polyester resins, polycarbonate (PC), modified polycarbonates, polyamide resins such as polyamide 66, polyamide 6, polyamide 46, polyoxymethylene copolymer, polyoxy) Polyacetal (POM) resins such as methylene homopolymer, other engineering resins, super engineering resins such as polyethersulfone (PES), polyetherimide (PEI), thermoplastic polyimide (TPI), polyetherketone ( PEK), polyether ether ketone (PEEK), polyphenylene sulfide (PSU), cellulose acetate (CA), cellulose acetate butyrate (CAB), ethyl Agarose rules may include a liquid crystal polymer such as (EC), such as a cellulose derivative, a liquid crystal polymer, a liquid crystal aromatic polyester. In addition, thermoplastic polyurethane elastomer (TPU), thermoplastic styrene butadiene elastomer (TSBC), thermoplastic polyolefin elastomer (TPO), thermoplastic polyester elastomer (TPEE), thermoplastic vinyl chloride elastomer (TPVC), thermoplastic polyamide elastomer (TPAE), etc. Thermoplastic elastomers may also be used. In this embodiment, you may use the blend of 1 type, or 2 or more types of thermoplastic resin, or may contain and use an additive material.

Hereinafter, in the manufacturing method of the resin molding of this invention, the case where a resin film is manufactured as a resin molding is demonstrated in detail using FIG.

FIG. 1: is a figure which shows typically the structure of the resin film manufacturing apparatus 100 used by the manufacturing method of the resin molded object which is one Embodiment of this invention. 2 is a cross-sectional view schematically showing the configuration of the polymer filter 12.

The resin film manufacturing apparatus 100 includes the extruder 1, the polymer filter 12, the die 2, the first cooling roll 3, the second cooling roll 4, and the third cooling roll. (5) and the takeout roll 6 are included. The polymer filter 12 includes a housing 14, a plurality of filter elements 13 formed in the housing 14, and a center pole 15.

The manufacturing method of the resin molded object of this invention is a method of manufacturing the resin film which consists of a thermoplastic resin which has a predetermined MVR value, and it is preferable to include an extrusion process, a filtration process, a film forming process, and a cooling process. The film forming step, which is a molding step, is a step of molding the thermoplastic resin obtained after the filtration step.

In the extrusion process, the thermoplastic resin is melted and the molten thermoplastic resin (molten resin) is extruded from the extruder 1.

The extruder 1 includes an extruder cylinder, a heater, and an extruder screw, not shown. In the extruder 1, the thermoplastic resin is melted by the heat from the heater and the shear frictional heat of the extruder screw in the extruder cylinder, and the thermoplastic resin (molten resin) in the molten state is extruded by the extruder screw to form a polymer. Send to filter 12.

In the filtration process, the molten resin extruded from the extruder 1 is filtered by the polymer filter 12 containing the some filter element 13. In this embodiment, the polymer filter 12 (filtration precision: 10 micrometers, element diameter size: 7 inch, element number: 40 sheets) by Fuji Filter Industry Co., Ltd. is used as the polymer filter 12. As shown in FIG. Filtration is performed by sending molten resin into the housing 14, passing each filter element 13, and sending it out from the center pole 15 toward the die 2.

In the film forming process, the thermoplastic resin after the filtration treatment is extruded from the die 2 into a film to form a film. As the die 2, a T die is usually used.

In a cooling process, the film-form thermoplastic resin (film-like resin) 10 extruded at the film forming process is cooled using a 1st cooling roll, a 2nd cooling roll, and a 3rd cooling roll, and the resin film 11 is obtained.

In the filtration step, a thermoplastic resin having a MVR value larger than a predetermined MVR value, that is, a thermoplastic resin having a predetermined MVR value, is passed through the polymer filter 12 with a low viscosity thermoplastic resin of the same type of thermoplastic resin. The thermoplastic resin having a predetermined MVR value is passed through the polymer filter 12. Thereby, breakage of the polymer filter 12 which arises by passing the thermoplastic resin with high viscosity at once can be prevented.

For example, in the filtration process, 3? The first filtration step of passing the thermoplastic resin having a MVR value of five times through the polymer filter 12, and 2 to the predetermined MVR value. It is preferable to include the 2nd filtration process which passes the thermoplastic resin which has a triple MVR value through the polymer filter 12, and the 3rd filtration process which passes the thermoplastic resin which has a predetermined MVR value through the polymer filter 12. Do. The third filtration step is a step of passing the thermoplastic resin having a high viscosity through the polymer filter 12. In the first filtration step and the second filtration step, the thermoplastic resin having the MVR value within the numerical range is sequentially passed through the polymer filter 12, so that the thermoplastic resin having a high viscosity is passed through the polymer filter (12) in the third filtration step. ), Damage to the polymer filter 12 can be reliably prevented.

In this way, the filtration step is a first filtration step. As the third filtration step is included, the extrusion step includes a first extrusion step of extruding the molten resin filtered in the first filtration step, a second extrusion step of extruding the molten resin filtered in the second filtration step, and And a third extrusion step of extruding the molten resin filtered in the third filtration step, wherein the film forming step includes a first film forming step of extruding the molten resin filtered in the first filtration step from the die 2 into a film form; 2nd film forming process which extrudes the molten resin filtered by the 2 filtration process from the die | dye 2 into a film form, and the 3rd film forming process which extrudes the molten resin filtered by the 3rd filtration process from the die | dye 2 into a film form Include.

In the first extrusion process, the extruder 1 is used to retract 3 to a predetermined MVR value in a state in which the first cooling roll 3, the second cooling roll 4, and the third cooling roll 5 are evacuated. ? The thermoplastic resin having a 5 times MVR value is melted by the extruder 1, and the molten resin is sent to the polymer filter 12. In a 1st filtration process, the molten resin extruded at the 1st extrusion process is passed through the polymer filter 12, and a filtration process is performed. Subsequently, in the 1st film forming process, the molten resin filtered by the 1st filtration process and sent from the piping 7 is extruded from the die 2 into a film form. The film-like resin extruded from the die 2 is recovered as a non-product.

In the 2nd extrusion process, the 2nd cooling roll 3, the 2nd cooling roll 4, and the 3rd cooling roll 5 were retracted, and the extruder 1 was used, and 2 with respect to a predetermined MVR value was used. ? The thermoplastic resin having a triple MVR value is melted in the extruder 1 and the molten resin is sent to the polymer filter 12. In the 2nd filtration process, the molten resin extruded at the 2nd extrusion process is passed through the polymer filter 12, and a filtration process is performed. Next, in a 2nd film forming process, the molten resin filtered by the 2nd filtration process and sent from the piping 7 is extruded from the die 2 into a film form. The film-like resin extruded from the die 2 is recovered as a non-product.

In the 3rd extrusion process, the retracted 1st cooling roll 3, the 2nd cooling roll 4, and the 3rd cooling roll 5 cool the film-form resin 10 from a normal position, ie, the die 2, and the like. In the state which returned to the position which can be returned, the extruder 1 is used and the thermoplastic resin which has a predetermined MVR value is melted by the extruder 1, and a molten resin is sent to the polymer filter 12. FIG. In a 3rd filtration process, the molten resin extruded at the 3rd extrusion process is passed through the polymer filter 12, and a filtration process is performed. Next, in the 3rd film forming process, the molten resin filtered by the 3rd filtration process and sent from the piping 7 is extruded from the die 2 into a film form.

Thus, the film-like resin 10 extruded from the die 2 in the 3rd film forming process is cooled by the cooling process, and is taken out by the take-up roll 6 after that, as a product resin film 11 It is wound up.

In a cooling process, the film-form resin 10 is cooled using the 1st cooling roll 3 and the 2nd cooling roll 4, and a resin film is obtained.

The 1st cooling roll 3 and the 2nd cooling roll 4 are mutually arrange | positioned, and sandwich the film-form resin 10 extruded from the die 2 between them. The 1st cooling roll 3 consists of a rubber roll or a metal elastic roll.

When using a rubber roll as the 1st cooling roll 3, a silicone rubber roll, a fluororubber roll, etc. are used, for example. As a hardness of a rubber roll, it is A70 degrees? Measured according to JISK6225. A range of A90 ° is preferred. In order to make the hardness of a rubber roll the said predetermined value, it can implement arbitrarily, for example by adjusting the crosslinking degree and composition of the rubber which comprises a rubber roll.

The metal elastic roll which can be used as the 1st cooling roll 3 is a roll in which the inside of a roll is comprised from rubber and the outer peripheral part is comprised from the metal thin film which has bendability. Specifically, it is a roll which coat | covered the cylindrical stainless steel thin film on the silicon rubber roll. In addition, the metal elastic roll has a fluid injected into the inside of the roll, and the outer circumferential portion of the roll is made of a metal thin film, specifically, a cylindrical thin film made of stainless steel at the roll end part to fix the inside. The roll which enclosed the fluid may be sufficient.

It is preferable that the metal elastic roll has elasticity whose contact length with the 2nd cooling roll 4 becomes a predetermined value, for example. That is, as the 1st cooling roll 3, the cylindrical thin film made of stainless steel is fixed at the roll end, and the metal elastic roll which enclosed the fluid inside is demonstrated as an example, and the film-like resin 10 extruded from the die 2 is demonstrated. Is sandwiched between the first cooling roll 3 and the second cooling roll 4, the first cooling roll 3 is concave along the outer circumferential surface of the second cooling roll 4 via the film-like resin 10. Elastically deformed into the phase. As a result, the 1st cooling roll 3 and the 2nd cooling roll 4 contact with predetermined contact length through the film-form resin 10. FIG.

This contact length is the length which can transfer the uneven shape of the 2nd cooling roll 4 which is not shown in figure below to the film-form resin 10. FIG. In order to make the said contact length into a predetermined value, it can implement arbitrarily by adjusting the thickness of the 1st cooling roll 3, the sealing amount of the fluid enclosed in the 1st cooling roll 3, etc., for example.

It is preferable that a rubber roll or a metal elastic roll is comprised so that temperature control is possible. What is necessary is just to attach a backup cooling roll to each roll, for example to make temperature control the rubber roll and the metal elastic roll which coat | covered the cylindrical metal thin film on the rubber roll. Moreover, what is necessary is just to control temperature of a fluid in order to be able to temperature-control the metal elastic roll which enclosed the fluid in said inside. As the temperature control of the fluid, for example, a known control method such as PID control or ON-OFF control can be adopted.

As such a 1st cooling roll 3, it is a roll comprised from a metal material or an elastic body, and the roll finished mirror-likely by plating etc. is used. In addition, the surface of the metal thin film and the rubber roll of a metal elastic roll does not necessarily need to be smooth, and there exists no problem even if it forms an uneven | corrugated shape in the surface like the 2nd cooling roll 4 demonstrated below.

The 2nd cooling roll 4 consists of a metal roll in which the uneven shape was formed in the outer peripheral surface. Specifically, the metal roll etc. which can control the temperature of a roll surface through fluid, steam, etc. can be mentioned in the inside of rolls, such as the drill roll which scraped off the metal mass, the spiral roll of a hollow structure, etc., These The roll in which the desired uneven | corrugated shape was formed by the sand blast, engraving, etc. on the outer peripheral surface of a metal roll can be used.

As an uneven | corrugated shape formed in the outer peripheral surface of the 2nd cooling roll 4, it is 0.1 to arithmetic mean roughness Ra. In addition to the mat shape of 10 μm, the pitch and height are 5? The prism shape, lens shape, etc. which are 500 micrometers can be employ | adopted. The arithmetic mean roughness Ra is a value obtained by measuring with a surface roughness meter in accordance with JIS B 0601-2001.

The film-like resin 10 extruded from the die 2 is sandwiched between the first cooling roll 3 and the second cooling roll 4, so that the uneven shape of the second cooling roll 4 is formed. Is transferred and molded into a film. The resin film 11 to which the uneven shape is transferred is wound by the take-up roll 6 and wound up after being wound on the second cooling roll 4. In addition, both the 1st cooling roll 3 and the 2nd cooling roll 4 are connected to rotation drive means, such as an electric motor, and each cooling roll is comprised so that it may rotate at a predetermined | prescribed main speed. .

At this time, as shown in FIG. 1, you may form the 3rd cooling roll 5 after the 2nd cooling roll 4. As shown in FIG. Thereby, since the resin film 11 is cooled slowly, since the optical deformation of the resin film 11 can be made small, and also the contact time to the 2nd cooling roll 4 can be ensured stably, it is 2nd The concave-convex shape given to the cooling roll 4 can be reliably transferred. It does not specifically limit as the 3rd cooling roll 5, The conventional metal roll conventionally used by extrusion molding can be employ | adopted. As a specific example, a drilled roll, a spiral roll, etc. are mentioned. It is preferable that the surface state of the 3rd cooling roll 5 is a mirror surface.

The resin film 11 wound on the 2nd cooling roll 4 is passed between the 2nd cooling roll 4 and the 3rd cooling roll 5, and it is made to wind to the 3rd cooling roll 5. A predetermined gap may be formed between the second cooling roll 4 and the third cooling roll 5 to be in a released state, or may be sandwiched between both rolls. In addition, in cooling the resin film 11 more gently, after the 3rd cooling roll 5, it is 4th, 5th,... And n (n is natural water) and some cooling roll may be formed, and the resin film 11 wound by the 3rd cooling roll 5 may be sequentially wound to the next cooling roll.

The surface temperature T of the second cooling roll 4 is (Th-60 ° C) ≤ T ≤ (Th + 30 ° C) with respect to the heat deformation temperature Th of the film-like resin 10, preferably (Th-30 ° C) ≤ T ≤ (Th + 20 ° C), more preferably (Th-20 ° C) ≤ T ≤ (Th + 10 ° C).

It is preferable to make the surface temperature of the 1st cooling roll 3 into +/- 30 degreeC with respect to the surface temperature T of the 2nd cooling roll 4, Preferably it is in the range of +/- 20 degreeC. On the other hand, when the surface temperature of the 1st cooling roll 3 is out of the said range, it may become difficult to set the surface temperature T of the 2nd cooling roll 4 in the said specific range, and resin The temperature distribution in the film 11 becomes nonuniform, and there exists a possibility that optical deformation may become large.

About the surface temperature of each cooling roll after the 3rd cooling roll 5 and the 3rd cooling roll 5, what is necessary is just to set it to arbitrary surface temperature, although it does not specifically limit, Usually, the heat distortion temperature of a thermoplastic resin ( About Th) about 15 degreeC is preferable.

The heat distortion temperature (Th) of the thermoplastic resin is not particularly limited, but is usually 60? 200 ° C. The heat distortion temperature Th of a thermoplastic resin is the temperature measured based on ASTMD-648.

The take-up roll 6 consists of a pair of upper roll 6a and lower roll 6b. As upper roll 6a and lower roll 6b, a rubber roll, a metal roll, etc. are mentioned, for example. The lower roll 6b is connected to rotation drive means, such as an electric motor, and is arrange | positioned so that the upper roll 6a can freely rotate so that it may contact this lower roll 6b, and it is to rotate the lower roll 6b. The upper roll 6a is also rotated by this. Thus, the upper roll 6a and the lower roll 6b rotate at the same main speed. Moreover, as long as the circumferential speeds of the upper roll 6a and the lower roll 6b become the same, the structure opposite to the said structure, ie, the upper roll 6a, is connected to a rotation drive means, and this upper roll 6a and You may arrange | position so that the lower roll 6b may rotate freely so that it may contact, and the upper roll 6a and the lower roll 6b may be connected to rotation drive means.

The product resin film 11 taken out by the takeout roll 6 has a thickness of 30? It is preferable that it is 300 micrometers. On the other hand, when the thickness is less than 30 micrometers, in the roll structure mentioned above, the resin film 11 may not be obtained stably, and when it exceeds 300 micrometers, it may become difficult to handle as a film. The thickness of the resin film 11 can be adjusted according to the thickness of the film-form resin 10 extruded from the die 2, the space | interval of the 1st cooling roll 3 and the 2nd cooling roll 4, etc.

Since the uneven | corrugated shape is formed in the surface and the function which scatters light is provided, the resin film 11 is used, for example, in addition to a liquid crystal cell, retardation film, a diffusion film, a brightness enhancement film, etc. combined with an optical disc and a polarizing plate, etc. Although it can apply to the film for interior use, the film for illumination, the film for building materials, etc., this invention is not limited to these uses.

Hereinafter, the case where the resin film which consists of polycarbonate resin whose MVR value is 10 cm <3> / 10min or more and 20cm <3> / 10min or less is demonstrated.

The MVR value of polycarbonate resin is adjusted with the molecular weight of polycarbonate resin. By reducing the molecular weight, the MVR value can be increased. Although the MVR value of polycarbonate resin can be adjusted by heating, in this method, polycarbonate resin is not preferable because it causes thermal decomposition.

The MVR value of polycarbonate resin is measured based on ISO 1133, and is a value measured on 300 degreeC and 12 kg of load conditions.

In the 1st extrusion process, the MVR value is 60 cm <3> / 10min using the extruder 1, with the 1st cooling roll 3, the 2nd cooling roll 4, and the 3rd cooling roll 5 evacuated. 230 or more thermoplastic resins that are 80 cm <3> / 10 min or less It melts under the temperature of 280 degreeC, and sends molten resin to the polymer filter 12. In the first filtration step, the molten resin extruded in the first extrusion step is subjected to a temperature of 230 ° C. 280 ° C., pressure 0.0? Filtration is performed by passing through the polymer filter 12 under the condition of 3.5 MPa. Subsequently, in the 1st film forming process, the molten resin filtered by the 1st filtration process and sent from the piping 7 is extruded from the die 2 into a film form. The film-like resin extruded from the die 2 is recovered as a non-product.

The conversion from the first film forming process to the second extrusion process includes a polycarbonate resin having an MVR value of 60 cm 3/10 min or more and 80 cm 3/10 min or less in the first filtration step, at least twice the volume of the polymer filter 12. This is done when passed. In addition, the volume of the polymer filter 12 means the volume of the housing 14 minus the volume of the filter element 13 and the center pole 15. As shown in FIG.

In the 2nd extrusion process, the MVR value is 30 cm <3> / 10 using the extruder 1 in the state which retracted the 1st cooling roll 3, the 2nd cooling roll 4, and the 3rd cooling roll 5. In FIG. 230 to min. It melts under the temperature of 280 degreeC, and sends molten resin to the polymer filter 12. In the second filtration step, the molten resin extruded in the second extrusion step is subjected to a temperature of 230 ° C. 280 ° C., pressure 0.0? Filtration is performed by passing through the polymer filter 12 under the condition of 7.0 MPa. Next, in a 2nd film forming process, the molten resin filtered by the 2nd filtration process and sent from the piping 7 is extruded from the die 2 into a film form. The film-like resin extruded from the die 2 is recovered as a non-product.

The conversion from the second film forming process to the third extrusion process is performed by adding a polycarbonate resin having an MVR value of 30 cm 3/10 min or more and 50 cm 3/10 min or less in the second filtration step to 3 times or more of the volume of the polymer filter 12. This is done when passed.

In the 3rd extrusion process, the retracted 1st cooling roll 3, the 2nd cooling roll 4, and the 3rd cooling roll 5 cool the film-form resin 10 from a normal position, ie, the die 2, and the like. In the state of returning to the position where it can return, by using the extruder 1, the thermoplastic resin whose MVR value is 10 cm <3> / 10 min or more and 20 cm <3> / 10 min or less is used. It melts under the temperature of 295 degreeC, and sends a molten resin to the polymer filter 12. In the third filtration step, the molten resin extruded in the third extrusion step is subjected to a temperature of 280 ° C. 295 ° C., pressure 8.4? Filtration is performed by passing through the polymer filter 12 under the condition of 8.7 MPa. Next, in the 3rd film forming process, the molten resin filtered by the 3rd filtration process and sent from the piping 7 is extruded from the die 2 into a film form.

In the first filtration step and the second filtration step, the polycarbonate resin having a high viscosity in the above numerical range is sequentially passed through the polymer filter 12 to thereby pass the polycarbonate resin having a high viscosity in the third filtration step. Even if it passes through (12), the damage of the polymer filter 12 can be reliably prevented, and the resin film which consists of polycarbonate resin whose MVR values are 10 cm <3> / 10min or more and 20 cm <3> / 10min or less can be obtained.

1: extruder
2: Die
3: first cooling roll
4: second cooling roll
5: third cooling roll
6: takeover roll
12: polymer filter
100: resin film production apparatus

Claims (4)

A method of manufacturing a resin molded body made of a thermoplastic resin having a predetermined melt volume flow rate (MVR) value,
A filtration step of performing a filtration treatment by passing a molten thermoplastic resin extruded from an extruder through a polymer filter, wherein the thermoplastic resin having a melt volume flow rate value larger than the predetermined melt volume flow rate value is passed through the polymer filter. A filtration step of performing a filtration treatment after passing the thermoplastic resin having the predetermined melt volume flow rate value through the polymer filter;
And a molding step of molding the thermoplastic resin after the filtration treatment. The method of claim 1,
The filtration step,
3? For the predetermined melt volume flow rate value. A first filtration step of passing a thermoplastic resin having a melt volume flow rate value of five times through the polymer filter,
2 to the predetermined melt volume flow rate value; A second filtration step of passing the thermoplastic resin having a triple melt volume flow rate value through the polymer filter,
And a third filtration step of passing the thermoplastic resin having the predetermined melt volume flow rate value through the polymer filter. The method of claim 2,
The predetermined melt volume flow rate value is 10 cm 3/10 min or more and 20 cm 3/10 min or less,
In the first filtration step, a thermoplastic resin having a melt volume flow rate value of 60 cm 3/10 min or more and 80 cm 3/10 min or less is passed through the polymer filter,
In the second filtration step, a thermoplastic resin having a melt volume flow rate value of 30 cm 3/10 min or more and 50 cm 3/10 min or less is passed through the polymer filter. The method of claim 3, wherein
The said thermoplastic resin is polycarbonate resin, The manufacturing method of the resin molded object characterized by the above-mentioned.

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