JP2000280315A - Extruded molding of cyclic olefin resin and manufacture thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a surface smoothness which is satisfactory enough to make an extruded molding of a cyclic olefin resin applicable to an optical use by setting the surface coarseness of the molding at a specific level or less in terms of maximum coarseness Rt. SOLUTION: A cyclic olefin resin 2 as a molding material is supplied from a hopper 3 and this supplied resin 2 is moved to an adapter part 5 by a screw while being thermally melted in a cylinder 4 and then is pressurized to be extruded from the adapter part 5 through a T-die 6. Further, the molten resin of a short paper strip shape extruded from the T-die 6 is cooled using a plurality of cooling rolls 7, and thus a resin sheet or a resin film 8 with the surface coarseness set at 0.3 μm or less in terms of maximum coarseness Rt is obtained to be taken up by a take-up machine 9. Consequently, it is possible to obtain a surface smoothness which is satisfactory enough to make the resin sheet or the resin film 8 applicable to an optical use and the like.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a cyclic olefin resin extruded product and a method for producing the same, and more particularly, to a cyclic olefin resin extruded product having excellent smoothness and a method for producing the same.

[0002]

2. Description of the Related Art By extrusion molding of a cyclic olefin resin,
It is known that sheets, films and the like can be obtained (see JP-A-3-223328).

[0003] As the extrusion molding method, T-die molding,
Extrusion molding, such as inflation molding and heteromorphic molding, is performed by extruding a cyclic olefin resin from a die in a molten state by an extruder such as a single screw (or twin screw), and continuously withdrawing the same to obtain a desired cross sectional shape. The method of making things is common.

Here, as a material of a die used for extrusion molding by an extruder, stainless steel such as SUS316 and carbon steel such as S45C are generally used. When an extruded product such as a sheet or a film made of a cyclic olefin resin is produced, there is a problem that a die line is generated on the surface and an extruded product having excellent surface smoothness cannot be obtained. Here, the “die line” means a stripe observable to the naked eye continuously generated along a resin extrusion direction at a position of a molded product corresponding to a specific position of the die. Specifically, it refers to stripes formed on a molded product whose surface irregularities have a height of about 0.3 μm to 100 μm (the irregularities below this range cannot be observed with the naked eye).

Depending on the type of resin, there are die lines that are easy to appear (conspicuous) and those that are hard to come out (inconspicuous). However, in the case of a cyclic olefin resin, there is a problem that die lines are likely to appear. This die line cannot be prevented even by changing the conditions of extrusion molding, and in the case of a conventional cyclic olefin resin extruded product, uniformity of appearance and uniformity of thickness of the molded product are problematic. However, it has been difficult to apply it to applications that require strict surface uniformity, such as optical applications.

In the case of a thin molded product such as a film, a molded product without a die line can be formed by a casting method of casting a cyclic olefin resin solution. Since heating is required, the productivity is low, and there are problems such as the solvent remaining in the molded article even after the drying step, which is not sufficient.

[0007]

Accordingly, the present inventors attempted to elucidate the cause of die line generation and to obtain a molded product made of a cyclic olefin resin having no die line by a melt extrusion method. It was considered to make it. However, when the resin temperature is increased,
Each of the die lines becomes smaller and relatively difficult to see, but the number of die lines increases as the operation time increases, because the die line causing substances, which are thought to be derived from the decomposition products of the resin, increase and adhere near the exit of the die. Increased. Conversely, when the resin temperature was lowered, the number of die lines decreased, but each one became larger and more prominent. Further, the cause of die line generation during extrusion molding of a cyclic olefin resin has not yet been elucidated, and a melt extruded product without a die line has not been obtained.

On the other hand, when the extruded product is in the form of a sheet or a film, the resin is generally extruded from a T-die in a molten state by an extruder such as a single-screw (or twin-screw) or the like, and this is taken up (cast) roll. The method of manufacturing by picking up by the method is adopted. When taking out the molten resin, the molten resin is pressed against the take-up roll with air.

However, with a conventional forming method in which a roll is in contact with only one side of a sheet or the like, a sheet having excellent smoothness (gloss) on both sides cannot be obtained. In particular, in fields where extremely high surface smoothness is required, such as recent optical applications, a cyclic olefin resin sheet having excellent smoothness (glossy) on both surfaces is required, which has become a problem. ing.

[0010] The present invention has been made in view of the above points, and an object of the present invention is to provide a molding made of a cyclic olefin resin having an excellent surface smoothness that can be applied to optical applications and the like. To provide a product by melt extrusion of a cyclic olefin resin.

Another object of the present invention is to prevent the generation of die lines in a method for melt-extruding a cyclic olefin resin, thereby enabling continuous molding over a long period of time and having a high surface smoothness. An object of the present invention is to dramatically improve the productivity of a resin molded product.

It is another object of the present invention to provide a sheet or film-shaped extruded product made of a cyclic olefin resin having excellent surface smoothness and a method for producing the same.

[0013]

That is, the cyclic olefin resin extruded product of the present invention has a maximum surface roughness R.
It is 0.3 μm or less in t notation.

The extruded product of the cyclic olefin resin of the present invention can be in the form of a sheet or a film. In such a case, the extruded product of the cyclic olefin resin has an average roughness of both surfaces. It is preferably 0.2 μm or less in Ra notation.

Further, in the extruded product made of a cyclic olefin resin of the present invention, the surface roughness is not more than 0.15 μm in terms of average roughness Ra and not more than 0.25 in terms of maximum roughness Rt.
Preferably it is 5 μm or less.

The method for producing a cyclic olefin resin extruded product of the present invention is characterized in that the cyclic olefin resin is melted, and the molten cyclic olefin resin is extruded through a die having a lip portion having a peel strength of 75 N or less. Is formed.

Further, the method of the present invention for producing a sheet or film-shaped extruded product made of a cyclic olefin resin comprises melting the cyclic olefin resin, extruding the molten cyclic olefin resin through a die, and extruding the extruded cyclic olefin resin. Is taken up by a smoothing roll comprising at least two opposing rolls and a pressing means provided to make the nip interval between the rolls constant, and forming the cyclic olefin resin into a sheet or film shape. Is what you do.

[0018]

DESCRIPTION OF THE PREFERRED EMBODIMENTS <Surface Roughness of Extruded Product> The extruded product made of a cyclic olefin resin in the present invention has a surface roughness of 0.3 μm or less, preferably 0.25 μm or less in terms of maximum roughness Rt. And more preferably 0.2 μm or less. When the maximum roughness Rt is in this range,
There are substantially no die lines on the molding surface.

Here, the “maximum roughness Rt” can be obtained as follows. First, the surface condition of the extruded product is measured using a stylus type surface roughness meter (JIS B 0651, etc.).
Is used to measure a fixed length (for example, a measurement length of 5 mm) in a direction perpendicular to the direction in which the extruded product is taken out, and creates a measurement curve (also referred to as a “cross-sectional curve”). Next, the obtained measurement curve is divided into a fixed reference length (for example, 0.8 mm), the maximum valley depth Rvi and the maximum peak height Rpi within each reference length are obtained, and the maximum value among them is obtained. Are defined as Rv and Rp, and are calculated by the following general formula, Rt = Rv + Rp.

As described above, the extruded product made of a cyclic olefin resin having excellent surface smoothness according to the present invention is characterized by having no die line. In some cases, it is preferable that the molded product has no microscopic irregularities on the surface of the molded product in addition to the die line. Here, the surface roughness related to microscopic irregularities on the surface of the molded product can be represented by “average roughness Ra”.

That is, the sheet or film of the present invention preferably has a surface roughness of at least one side, preferably both sides, of 0.2 μm or less, more preferably 0.15 μm, in terms of average roughness Ra. The thickness is more preferably 0.05 μm or less. When the average roughness Ra is in this range, no microscopic unevenness is observed on the surface of the molded product. In the present invention, the average roughness Ra is J
This is the same as “arithmetic mean roughness Ra” defined by IS B 0601-1994. Specifically, the measurement curve used for calculating the maximum roughness Rt described above is phase compensated at a cutoff value of 0.8 mm. Determine the roughness curve through the mold high-pass filter, extract a certain reference length from the roughness curve in the direction of the average line, sum the absolute value of the deviation from the average line to the roughness curve of the extracted portion, It is determined by averaging.

<Cyclic Olefin Resin> Next, the cyclic olefin resin used in the extruded product of the present invention has an alicyclic structure in the main chain and / or side chain, and has mechanical strength and heat resistance. From the viewpoint of the above, those containing an alicyclic structure in the main chain are preferred. As the alicyclic structure of the polymer,
Examples include a saturated cyclic hydrocarbon (cycloalkane) structure and an unsaturated cyclic hydrocarbon (cycloalkene) structure.
Among them, a cycloalkane structure is most preferable because of its excellent durability and chemical resistance. The number of carbon atoms constituting the alicyclic structure is not particularly limited, but is usually 4 to 30, preferably 5 to 20.
When the number is in the range of 5 pieces, more preferably 5 to 15, the properties of mechanical strength, heat resistance and moldability are highly balanced and suitable.

The proportion of the repeating unit having an alicyclic structure in the cyclic olefin resin used in the present invention may be appropriately selected according to the purpose of use, but is usually 30% by weight or more, preferably 50% by weight. As described above, the content is more preferably 70% by weight, and most preferably 100% by weight. If the proportion of the repeating unit having an alicyclic structure in the cyclic olefin resin is small, the heat resistance is poor, which is not preferable. The remainder other than the repeating unit having an alicyclic structure in the cyclic olefin resin,
There is no particular limitation, and it is appropriately selected according to the purpose of use.

Specific examples of such a polymer resin having an alicyclic structure include (1) a norbornene-based polymer,
Examples thereof include (2) a monocyclic cycloolefin polymer, (3) a cyclic conjugated diene polymer, (4) a hydrocarbon polymer having a side chain alicyclic structure, and hydrogenated products thereof. Among these, norbornene-based polymers and hydrogenated products thereof, cyclic conjugated diene-based polymers and hydrogenated products thereof are preferable, and norbornene-based polymers and hydrogenated products thereof are more preferable.

(1) Norbornene-based polymer The norbornene-based polymer is not particularly limited. For example, JP-A-3-14882 and JP-A-3-122.
A polymer obtained by polymerizing a norbornene-based monomer by a method disclosed in, for example, JP-A-137-137 is used. In particular,
Examples include ring-opening polymers of norbornene monomers and hydrogenated products thereof, addition polymers of norbornene monomers, and addition polymers of norbornene monomers and vinyl compounds. Among them, in order to highly balance heat resistance and dielectric properties, hydrogenated ring-opening polymer of norbornene-based monomer, addition-type polymer of norbornene-based monomer, and copolymerization with norbornene-based monomer Preferred are addition polymers with a possible vinyl monomer, and hydrogenated ring-opening polymers of norbornene monomers are particularly preferred.

As the norbornene-based monomer, bicyclo
[2.2.1] Hept-2-ene (common name norbornene)
), 5-methyl-bicyclo [2.2.1] hepta-2
-Ene, 5,5-dimethyl-bicyclo [2.2.1]
Pt-2-ene, 5-ethyl-bicyclo [2.2.1]
Hept-2-ene, 5-butyl-bicyclo [2.2.
1] Hept-2-ene, 5-hexyl-bicyclo [2.
2.1] Hept-2-ene, 5-octyl-bicyclo
[2.2.1] Hept-2-ene, 5-octadecyl-
Bicyclo [2.2.1] hept-2-ene, 5-ethyl
Den-bicyclo [2.2.1] hepta-2-ene, 5-
Methylidene-bicyclo [2.2.1] hepta-2-e
5-vinyl-bicyclo [2.2.1] hepta-2-
Ene, 5-propenyl-bicyclo [2.2.1] hepta
-2-ene, 5-methoxy-carbonyl-bicyclo
[2.2.1] Hept-2-ene, 5-cyano-bisic
B [2.2.1] Hept-2-ene, 5-methyl-5-
Methoxycarbonyl-bicyclo [2.2.1] hepta
2-ene; 5-methoxycarbonylbicyclo [2.
2.1] Hept-2-ene, 5-ethoxycarbonylbi
Cyclo [2.2.1] hept-2-ene, 5-methyl-
5-methoxycarbonylbicyclo [2.2.1] hept
-2-ene, 5-methyl-5-ethoxycarbonylbis
Chromo [2.2.1] hept-2-ene, bicyclo [2.
2.1] Hept-5-enyl-2-methylpropione
G, bicyclo [2.2.1] hept-5-enyl-2-
Methyl octanate, bicyclo [2.2.1] hept-
2-ene-5,6-dicarboxylic anhydride, 5-hydroxy
Cimethylbicyclo [2.2.1] hept-2-ene,
5,6-di (hydroxymethyl) bicyclo [2.2.
1] Hept-2-ene, 5-hydroxy-i-propyl
Bicyclo [2.2.1] hept-2-ene, 5,6-di
Carboxybicyclo [2.2.1] hept-2-ene;
 5-cyanobicyclo [2.2.1] hept-2-e
, Bicyclo [2.2.1] hept-2-ene-5,6
-Dicarboxylic imide; tricyclo [4.3.0.1
^{twenty five}] Deca-3,7-diene (common name dicyclopentadiene)
Ene), tricyclo [4.3.0.1^{twenty five}] Deca-3-
Ene; tricyclo [4.4.0.1^{twenty five}] Undeca
3,7-diene or tricyclo [4.4.0.1
^{twenty five}] Undeca-3,8-diene or partial water thereof
Additive (or cyclopentadiene and cyclohexene
Tricyclo [4.4.0.1)^{twenty five}]
Ndeca-3-ene; 5-cyclopentyl-bicyclo
[2.2.1] Hept-2-ene, 5-cyclohexyl
-Bicyclo [2.2.1] hept-2-ene, 5-cycl
Rohexenylbicyclo [2.2.1] hept-2-e
5-phenyl-bicyclo [2.2.1] hept-2
-Ene; tetracyclo [4.4.0.1^{twenty five}. 1
^{7, 10}] -Dodec-3-ene (simply tetracyclododece
8-methyltetracyclo [4.4.0.
1^{twenty five}. 1 ^{7, 10}] -Dodeca-3-ene, 8-ethylte
Toracyclo [4.4.0.1^{twenty five}. 1^{7, 10}]-Dodeca
-3-ene, 8-methylidenetetracyclo [4.4.
0.1^{Two , Five}. 1^{7, 10}] -Dodeca-3-ene, 8-ethyl
Lidentetracyclo [4.4.0.1^{twenty five}. 1^{7, 10}]
-Dodec-3-ene, 8-vinyltetracyclo [[4.
4.0.1.^{twenty five}. 1^{7, 10}] -Dodeca-3-ene, 8-
Propenyl-tetracyclo [4.4.0.1^{twenty five}. 1
^{7, 10}] -Dodeca-3-ene, 8-methoxycarbonyl
Tetracyclo [4.4.0.1^{twenty five}. 1^{7, 10}]-Dode
Car-3-ene, 8-methyl-8-methoxycarbonyl
Toracyclo [4.4.0.1^{twenty five}. 1^{7, 10}]-Dodeca
-3-ene, 8-hydroxymethyltetracyclo [4.
4.0.1.^{twenty five}. 1^{7, 10}] -Dodeca-3-ene, 8-
Carboxytetracyclo [4.4.0.1^{twenty five}. 1
^{7, 10}] -Dodeca-3-ene; 8-cyclopentyl-
Tetracyclo [4.4.0.1^{twenty five}. 1^{7, 10}]-Dode
Car-3-ene, 8-cyclohexyl-tetracyclo
[4.4.0.1^{twenty five}. 1^{7, 10}] -Dodeka-3-e
8-cyclohexenyl-tetracyclo [4.4.
0.1^{twenty five}. 1^{7, 10}] -Dodeca-3-ene, 8-fe
Nyl-cyclopentyl-tetracyclo [4.4.0.1
^{twenty five}. 1 ^{7, 10}] -Dodeca-3-ene; tetracyclo
[7.4.0.1^{10, 13}. 0^{2, 7}] Trideca-2,4
6,11-tetraene (1,4-methano-1,4,4
a, 9a-tetrahydrofluorene), tetra
Cyclo [8.4.0.1^{11, 14}. 0^{3, 8}] Tetradeca
3,5,7,12-tetraene (1,4-methano-1,
4,4a, 5,10,10a-Hexahydroanthrace
Pentacyclo [6.5.1.1]^{3, 6}. 0
^{2, 7}. 0^9,13] Pentadeca-3,10-diene, pentane
Cyclo [7.4.0.1^{3, 6}. 1^{10, 13}. 0^{2, 7}]pen
Tadeca-4,11-diene; cyclopentadiene 4
Norbornene-based monomers such as
You. Each of these norbornene monomers alone
Alternatively, two or more kinds are used in combination.

The polymerization method and hydrogenation method of the norbornene monomer or the vinyl monomer copolymerizable with the norbornene monomer are not particularly limited, and can be carried out according to known methods.

The ring-opening (co) polymer of the norbornene-based monomer is obtained by converting the norbornene-based monomer into ruthenium, rhodium,
A catalyst system comprising a halide, nitrate or acetylacetone compound of a metal such as palladium, osmium, iridium and platinum and a reducing agent; or titanium,
Polymerization temperature of -50 ° C to 100 ° C, usually in a solvent or in the absence of a solvent, using a catalyst system comprising a halide or acetylacetone compound of a metal such as tungsten or molybdenum and an organoaluminum compound, 0 to 50 k
It can be obtained by ring-opening (co) polymerizing at a polymerization pressure of g / cm ² .

The addition copolymer of a norbornene-based monomer and a vinyl-based compound may be prepared, for example, by mixing a monomer component in a solvent or without a solvent with a vanadium compound and an organic aluminum compound (preferably a halogen-containing organic aluminum compound).
In the presence of a catalyst system consisting of
It can be obtained by a method of copolymerizing at a polymerization temperature of 0 ° C. and a polymerization pressure of 0 to 50 kg / cm ² .

The hydrogenated norbornene-based polymer can be obtained by a conventional method in which a ring-opened (co) polymer is hydrogenated with hydrogen in the presence of a hydrogenation catalyst.

(2) Monocyclic Cyclic Olefin Polymer Examples of the monocyclic cycloolefin polymer include, for example, cyclolohexene, cycloheptene and cyclooctene disclosed in JP-A-64-66216. An addition polymer of a monocyclic cyclic olefin monomer can be used.

(3) Cyclic conjugated diene-based polymer As the cyclic conjugated diene-based polymer, for example, Japanese Unexamined Patent Publication No.
The cyclic conjugated diene-based monomers such as cyclopentadiene and cyclohexadiene disclosed in JP-A-136057 and JP-A-7-258318 are used as 1,2- or 1,2-
4-Polymerized polymers and hydrogenated products thereof can be used.

(4) Hydrocarbon polymer having an alicyclic structure in the side chain The hydrocarbon polymer having an alicyclic structure in the side chain includes:
For example, use of polymers of vinyl alicyclic hydrocarbon monomers such as vinylcyclohexene and vinylcyclohexane and hydrogenated products thereof, and hydrogenated products of hydrocarbon polymers having an aromatic ring in a side chain such as polystyrene. Can be.

The molecular weight of the cyclic olefin resin used in the present invention is appropriately selected according to the purpose of use, but it is determined by gel permeation chromatography of a cyclohexane solution (a toluene solution when the polymer resin is not dissolved). The number average molecular weight in terms of polyisoprene measured in
000 to 500,000, preferably 8,000 to 20
0000, particularly preferably 10,000-100,0.
00; usually 10,000 to 1,000 in weight average molecular weight
0000, preferably 15,000 to 500,000
0, particularly preferably from 20,000 to 200,000. The molecular weight distribution is usually from 1.0 to 10, preferably from 1.0 to 6, particularly preferably from 1.1 to 4. When it is in such a range, the mechanical strength of the obtained sheet and the workability in forming the sheet are well-balanced and suitable.

The glass transition temperature (Tg) of the cyclic olefin resin used in the present invention may be appropriately selected according to the purpose of use, but is preferably higher in view of the use environment of the molded product, and is usually 40 to 400 ° C. , Preferably 60-300 ° C,
More preferably, it is 80 to 250 ° C. When Tg is in this range, the moldability is good and a sheet having a desired shape can be efficiently obtained.

The 5% loss on heating of the cyclic olefin resin used in the present invention (measured in a nitrogen atmosphere at a heating rate of 5 ° C./min) is preferably at least 280 ° C., particularly preferably at least 350 ° C. is there. If the 5% heating loss temperature is too low, the resin will be decomposed when the resin temperature is raised to improve the fluidity during melt molding, and molding defects such as inclusion of bubbles in the molded product due to decomposition will occur. There is a problem that it is easy. When the 5% heating loss temperature is in the above range, even if the resin temperature is increased, molding defects such as inclusion of bubbles are less likely to occur even if the resin temperature is increased for the purpose of improving fluidity during melt molding.

The melt viscosity of the cyclic olefin resin used in the present invention at a temperature of 260 ° C. is usually from 1 × 10 ¹ to 1
× 10 ⁵ poise, preferably 1 × 10 ² to 1 × 10 ⁴ poise. When the melt viscosity is in this range, the moldability of the sheet and the mechanical strength of the sheet are well balanced and suitable.

<Additives> In the cyclic olefin resin used in the present invention, other polymers, various compounding agents, and fillers can be used alone or in combination of two or more, if necessary.

When the above components (other polymers, compounding agents and fillers) are used, they may be added in the step of producing the alicyclic structure-containing polymer resin (for example, they are contained in the resin after synthesis). The solvent used in the synthesis is removed by a coagulation method or a direct drying method, and the above-mentioned various additives are added in necessary amounts). Is also good.

<Preliminary Drying of Cyclic Olefin Resin> The cyclic olefin resin of the present invention is usually used as pellets in the melt extrusion step. That is, the resin material is usually supplied as a pellet having a diameter of about 1 to 7 mm and a length of about 3 to 8 mm, and is formed into a desired shape by an extrusion molding method. In the case of a cyclic olefin resin, approximately 200
The mixture is extruded into a strand having a predetermined diameter in a molten state at a temperature of not less than ° C., and then cut into a desired length by an appropriate strand cutter and pelletized.

Here, when used as pellets, it is preferable that the pellets be pre-dried and used in order to obtain a molded product having no fine voids or crack-like defects which cannot be seen with the naked eye. The sheet obtained by using the predried pellets has no microvoids even after molding, and further has a relative humidity of, for example, 70 ° C. or more.
Microvoids do not occur even after a durability test at a high temperature and high humidity of 0% or more and 20 hours or more. It has also been confirmed that this predrying treatment is effective for injection molding.

As conditions for the pre-drying, it is effective that the temperature is high and the drying time is long, but if the temperature is higher than the glass transition temperature (Tg) of the resin, the pellets are thermally fused. (Tg-30) to (Tg-30) are preferable because the use becomes difficult and the effect is saturated in several hours.
5) ° C, particularly preferably (Tg-20) to (Tg-5)
It is desirable to carry out the treatment at a temperature of at least 1 hour, particularly preferably at least 2 hours. Drying is effective in both vacuum drying and normal pressure drying in an air or nitrogen atmosphere. Further, it is preferable that the time from the end of the drying treatment to the time of use for molding is shorter.

<Molded Article> The extruded article of the present invention includes:
In addition to films and sheets, split fibers, nets, fibers, plate materials, tubes, tubes, bags, covered electric wires, foamed materials and the like can be mentioned.

<Manufacturing Method of Extruded Product> Next, a preferred method of manufacturing the extruded product made of the cyclic olefin resin of the present invention will be described based on the melt extruded film or sheet forming apparatus shown in FIG. FIG. 1 shows a case where the molded product is a film or a sheet, but the present invention is not limited to this method.

FIG. 1 shows an example of a melt-extruded film or sheet forming apparatus 1. The cyclic olefin resin 2 as a molding material is usually used in the form of a pellet as described above, and is supplied from the hopper 3. The molding material supplied from the hopper 3 is heated and melted in the cylinder 4, moves to the adapter unit 5 by a screw (not shown) and is pressurized, and the die 6 (T die) is removed from the adapter unit 5. Extruded through. The strip-shaped molten resin extruded from the T-die 6 is usually cooled by a plurality of cooling rolls 7 to form a sheet or a film 8 and wound by a winder 9.

Following melt kneading with various additives and other polymers, sheet melt extrusion can be performed. In this case, instead of the single screw extruder shown in FIG. A pressurizing machine such as a gear pump (not shown) is used in combination with a melt kneader (not shown) or the like, if necessary.
Further, after the resin is synthesized, it is also possible to directly mold the molten resin from a dryer or the like into a sheet without pelletizing. In this case, instead of the single screw extruder of FIG.
A pressurizing machine such as a gear pump is used. Even when such a method is used, it is possible to produce the extruded product of the present invention.

<Extruder etc.> When a single screw extruder, a twin screw extruder or a melt kneader is used, it is also preferable to reduce the oxygen concentration in the hopper and the melting zone of the cylinder by vacuum or nitrogen purge. Excellent colorless transparency,
This is because a sheet with little deterioration can be obtained. The oxygen partial pressure in this case is preferably 5000 Pa or less, particularly preferably 2000 Pa or less, and more preferably 1000 Pa or less.

The shape of the screw used in the single screw extruder or the twin screw extruder is appropriately selected and is not particularly limited. In the case of a single screw extruder, a metering type screw or a full flight screw similar to those used in sheet extrusion molding of polyethylene or polypropylene can be used. In the case of a single screw extruder, the screw usually has a diameter of 40 to 2
Thickness of about 00 mm is used, and L / D is usually 20 to 3
5, preferably 25-30, and the compression ratio is preferably 2.5-4. The number of rotations of the screw is appropriately selected depending on the relationship between the melt viscosity and the temperature of the resin used, the melt temperature, the required discharge amount, and the capacity of the power.

The melting temperature of the resin is appropriately selected depending on the discharge amount, the desired thickness of the sheet and the like, and is not particularly limited. Preferably, the melting temperature is usually (Tg + 30) to (Tg + 30) based on the glass transition temperature (Tg) of the molding material. Tg + 180)
° C, preferably (Tg + 50) to (Tg + 150) ° C,
Particularly preferably, the temperature is (Tg + 60) to (Tg + 140) ° C. When in this range, the sheet formability and
This is because the resulting sheet has an excellent balance of surface accuracy (surface roughness) and colorless transparency.

<Die> The pressed molten resin is extruded from an appropriate die as a strip-shaped molten resin. The die may be of a shape commonly used for forming sheets and films. For example, when forming a film or sheet, besides a coat hanger type and a straight manifold type, a fishtail type die can be suitably used for a sheet having a small width of about 50 to 500 mm, and particularly a sheet having a width of 300 mm or less is formed. In this case, a manifold type die (T die) with a choke bar is generally and preferably used.

As a specific example of the structure of the die, when the molded product is a sheet or a film, a T as shown in FIG.
Dies can be used. Here, reference numeral 100 denotes a die body, 101 denotes a lip portion, 102 denotes an adjustment bolt,
103 indicates a resin inlet. When the molded product is an inflation film, an inflation die is used.
When the molded product is a pipe, a straight head die can be used.

The temperature of the die is set to approximately the same as the resin temperature of the adapter. The width of the opening of the die is appropriately selected depending on the thickness of the target sheet or film, and is usually about 0.1 to 3 mm.

The method for forming a sheet or film of the present invention is applicable regardless of the width of the sheet or film, for example, from a narrow width of about 50 mm to a wide width of 2000 mm or more. The thickness is 10 μm to 3 mm
It is adaptable to the order.

The die is usually made of stainless steel, die steel, S
It is made of carbon steel such as 45C. And
The die preferably used in the present invention has a peel strength of 7
It has a lip portion of 5N or less, preferably 50N or less. When a die having such a peel strength is used, it is possible to prevent the thermal decomposition product of the molten cyclic olefin resin and the high-temperature molten product from adhering to the lip portion, and no die line is generated on the surface of the molded product. Become like

Here, the peel strength was determined by first placing a resin pellet on a test piece having the same surface as the lip,
After leaving it in a 0 ° C. gear oven for 60 minutes, it was cooled to room temperature, and then measured with a measuring device (universal tensile compression tester; TCM
500 (manufactured by Shinko Tsushin Kogyo Co., Ltd.), an indenter made of a stainless steel plate having a thickness of 0.5 mm from an angle of 25 ° with respect to the surface of the test piece under the conditions of a compression load cell of 500 kgf and a compression speed of 1 mm / min. Was pressed to peel off the pellet from the lip.

In the die having such peel strength, the die (particularly, the lip portion) is made of carbide such as tungsten carbide such as WC or W ₂ C and has an average roughness Ra (average roughness R of the above-mentioned molded article).
a) is coated with a ceramic material such as a titanium compound such as titanium nitride (TiN), chromium nitride having a Ra of 0.05 μm or less, or H-Cr. Ra is 0.01μm by plating
It is produced by coating with the following. As a method of coating, a method such as vapor deposition or thermal spraying on the lip portion can be adopted.

In the die having such peel strength, the lip portion is made of the above-mentioned ceramic material, Fe-B-Mo alloy (made by Toyo Steel; V52, C50, etc.), Co-Cr-B
It is obtained by forming it from a steel material of an alloy (manufactured by Hitachi Metals; H50, etc.). A zirconia-based compound can be used as the ceramic material. Further, it can also be obtained by adjusting the surface roughness by a polishing method such as electrolytic polishing. Here, the lip portion refers to an opening portion of the die which comes into contact with the molten plastic material when the material passes through the die for extrusion molding.

In the present invention, since the resin in the molten state passes through a die whose lip portion is coated with a ceramic or is made of a ceramic material, a thermal decomposition product of the resin and a granular material of a resin high-temperature melting product are used. Does not occur near the die exit. Therefore, there is no need to perform cleaning, and there is no damage to the lip portion due to cleaning, so that extrusion molding of a molded product without a die line can be performed continuously for a long time.

The surface accuracy of the lip is 1
S or less, more preferably 0.8 or less.
S, most preferably 0.4 S or less. Here, the unit “S” of the surface accuracy is four times the average roughness Ra [μm] of the surface of the die land calculated by the same method as the method for obtaining the average roughness Ra in the surface roughness of the molded product. For example, when Ra = 0.05 μm, the surface accuracy is 0.2S (0.05 × 4).

In the die for extrusion molding, except for the lip portion,
It is also preferable that a portion in contact with the molten plastic material (the surface of the die in contact with the portion where the molten resin flows in the die) is made of a ceramic coat or a ceramic material or the like so that the peel strength is within the above range. An extruded product having better smoothness can be obtained.

As described above, the pellet-shaped cyclic olefin resin 2 supplied to the hopper 3 of the extruder 10 is extruded from the die 6 after being melted by heating in the cylinder 4.
Then, it is formed into a desired shape by a method such as drawing with a roll.

<Smoothing Roll> When the extruded product is in the form of a sheet or a film, the extruded cyclic olefin resin is provided to keep the nip interval between at least two opposing rolls constant. The two rolls facing each other are preferably composed of a casting roll and a touch roll.

<Casting Roll> Here, the casting roll is usually fixed in position, has a roll diameter of usually about 100 to 600 mm, and has a cylindrical shape. This is a roll having voids through which a (cold) medium flows. A width (length) that is wider than the width of the target sheet is appropriately selected.

The material of the casting roll is not particularly limited. For example, rubber, carbon steel, stainless steel and the like can be mentioned. In the case of the present invention, in order to form a sheet having excellent surface accuracy, it is preferable to increase the surface accuracy of the casting roll, which is the same as the method for determining the average roughness Ra in the surface roughness of the molded product described above. 0.2 μm in the average roughness Ra of the casting roll calculated by the method
m or less, preferably 0.1 μm or less, more preferably 0.05 μm or less.

The temperature of the casting roll is usually (Tg-3) based on the glass transition temperature (Tg) of the resin.
0) to (Tg + 30) ° C, preferably (Tg-20) to
(Tg + 20) ° C. This is because, when it is in this range, the sheet has excellent thermal efficiency at the time of forming, and the obtained sheet has excellent flatness and surface smoothness. The number of revolutions (take-up speed) is appropriately selected according to the extrusion speed.

FIG. 3 is a schematic diagram showing the state from the exit of the die to the casting roll. The resin in a molten state from the die outlet 11 is slightly cooled in the air while being pulled by the casting roll 12,
Wrap around 2. At this time, the resin in the molten state acts to shrink due to surface tension, causing a phenomenon called neck-in in which the width of the molten resin becomes narrower than the exit of the die. The phenomenon of thickening occurs. This non-uniform thickness results in deterioration of the quality of the sheet and a decrease in usable portions of the sheet, which is not preferable. Here, the distance from the die exit to the casting roll is the air gap (the length indicated by L in FIG. 3).
However, in order to reduce neck-in and improve sheet quality and yield, it is preferable to shorten the air gap, which is achieved by adjusting the relative positions of the die and the casting roll.

<Touch Roll> In the invention of the present application,
For the resin wrapped around the casting roll 12,
It is preferable to press with the touch roll 13 from the opposite side of the casting roll 12 (see FIG. 3).

The touch roll 13 is usually cylindrical, and in order to keep the nip interval between the touch roll 13 and the casting roll 12 constant, the touch roll 13 is pressed against the casting roll 12 by the pressing means 14. I have. FIG. 3 illustrates a touch roll having a smaller diameter than the casting roll, but is not limited thereto.

The pressing means 14 is not particularly limited as long as the nip interval between the rolls can be made constant, and examples thereof include a spring and a hydraulic piston.

The width (length) of the touch roll is appropriately selected to be wider than the width of the target sheet. The material of the touch roll is not particularly limited. For example, rubber, carbon steel,
And stainless steel ceramics.

In the case of the present invention, in order to form a sheet having excellent surface accuracy, it is preferable to increase the surface accuracy of the touch roll, and to obtain the average roughness Ra in the surface roughness of the molded product described above. The average roughness Ra of the touch roll calculated by the same method as described above is 0.2 μm or less, preferably 0.1 μm or less, more preferably 0.05 μm.
It is preferable to set the following.

The temperature of the touch roll is adjusted by passing a cooling (heat) medium through the gap inside the roll. The temperature of the touch roll is usually (Tg-100) to (Tg + 30) C, preferably (Tg-90) to (Tg + 20) C, based on the glass transition temperature (Tg) of the resin. Also, compared to the temperature of the casting roll, usually the same temperature ~
The temperature is set lower by 50 ° C, preferably 5 to 40 ° C. When it is in this range, it has excellent thermal efficiency when forming the sheet,
Unnecessary winding of the film or sheet on the touch roll is prevented, and a sheet excellent in flatness and surface smoothness is obtained.

The number of rotations of the roll is appropriately selected. Also,
The ratio between the linear velocity of the surface of the touch roll and the linear velocity of the casting roll is appropriately selected and is usually 0.5 to 3 times. The linear pressure with which the touch roll presses the sheet (touches the sheet) can be adjusted by pressing means such as a spring or a hydraulic piston, and is preferably 5 to 150 kgf / cm, particularly preferably 10 to 100 kgf / cm.

<Special Touch Roll> A touch roll having a special shape can also be used. In the invention of the present application, in order to prevent uneven pressing due to uneven thickness corresponding to the neck-in and obtain uniform quality in the width direction, FIG.
(A) or a touch roll as shown in FIG. 4 (b), in which the diameter of both ends is reduced by providing a step or a taper in the thickness of the touch roll (FIG. 4 (a)), both sides (gray part in the figure) A touch roll with a band of elastic material such as rubber
It is preferable to use (b)). The influence of the thick portions at both ends (mimi) of the extruded cyclic olefin resin can be eliminated, and the central portion can be pressed uniformly.

In the case of a touch roll having a reduced diameter at both ends, the diameter at both ends is reduced stepwise or gradually. The width of the portion not to be reduced is 60 to 98% of the width of the desired sheet,
Preferably it is 70-95%. The difference in the diameter to be reduced is
Usually, 0.01 to 3 mm, preferably 0.02 to 2 mm
It is. Other specifications are the same as the above-mentioned cylindrical touch roll.

The touch roll having an elastic body wound at both ends is formed by winding an elastic body such as rubber or resin at both ends to form the same shape as the above-mentioned cylindrical touch roll as a whole. The width of the portion where the elastic body is not wound is 60 to 98%, preferably 70 to 98% of the desired sheet width.
~ 95%.

The thickness of the elastic body is 0.2 to 100 mm, preferably 0.5 to 20 mm.

The surface accuracy of the roll of the elastic portion is represented by the average roughness Ra of the roll portion calculated by the same method as the method for determining the average roughness Ra in the surface roughness of the molded product. 1 μm or less, preferably (0.5 μm
The following is preferred. Other specifications are the same as the above-mentioned cylindrical touch roll.

As another touch roll, a touch roll having a flexible roll surface as shown in FIG. 5 can be used. The touch roll includes a flexible sleeve 15 and a rubber roll 16. The rubber roll 16 is covered by the flexible sleeve 15, and a heat medium flows between the rubber roll 16 and the flexible sleeve 15. The surface of the flexible sleeve 15 is smooth. When the rubber roll 16 is pressed against the casting roll 12, the flexible sleeve 15 is pressed against the casting roll 12 in an arc shape, and the film or sheet is taken.

The extruded product taken up by the above-mentioned smoothing roll is cooled by a third roll or the like and then wound up once by a winder or as it is without being wound up.
It moves to the post-process. The winding machine is not particularly limited.

<Post-process> The obtained molded product may be used alone, or may be formed by laminating a film, a metal foil (or metal layer) cloth, paper, a net or the like made of the same or another polymer or the like. May be used. The lamination method is not particularly limited, and examples thereof include a dry lamination method, a hot melt lamination method, a vapor deposition method, a plating method, and a gas phase reactive vapor deposition method. At the time of lamination, an adhesive layer may be interposed if necessary, and the obtained sheet or film may be further stretched in a uniaxial or biaxial direction as necessary.

<Applications> The above-mentioned extruded products are excellent in surface smoothness, mechanical strength, chemical resistance, water vapor barrier property, etc., and are therefore used in foods, medicines (tablets, powders, liquid medicines, etc.), tobacco, etc. Packaging materials such as electronic components, daily necessities, and miscellaneous goods; Optical materials such as polarizing films, retardation films, liquid crystal substrates, light diffusing films, and prism films; Window materials and roof materials for automobiles, window materials for aircraft, and vending machines Window materials,
Window materials such as show window materials; resist container bags,
It is used as a material for medical solution bags such as medical solution bags and infusion bags; electric films such as electric insulating films, film capacitors and conductive films; building materials such as exterior materials and roofing materials.

[0083]

EXAMPLES The present invention will be specifically described below with reference to examples and comparative examples, but the present invention is not limited to these examples.

[0084]

Example 1 (Cyclic olefin resin) dicyclopentadi
85% by weight of ene and 15% by weight of ethyltetracyclododecene
% Of the hydrogenated product of the ring-opened polymer, and the weight average molecular weight (M
w) is 52,600 and the ratio of components having a molecular weight of 1,000 or less
Is 0.5% by weight, and the degree of hydrogenation of the polymer (¹H-NMR
Is 99.9%, and the glass transition temperature (DS
103 ° C., 5% heating limit temperature is 37 ° C.
At 5 ° C., the melt viscosity at 260 ° C. is 2 × 10 ^ThreePoise
Antioxidant to 100 parts by weight of cyclic olefin resin
Phenolic antioxidant [pentaerythrityl]
-Tetrakis (3- (3,5-di-tert-butyl)
-4-hydroxyphenyl) propionate)] 0.2
Parts by weight with a twin-screw kneader extruder to form pellets.
Shaped material (490K).

(Formation of Sheet) A sheet was formed from the above pellets by a melt extrusion sheet molding apparatus (single screw extruder) having a structure as shown in FIG. The manufacturing conditions were as follows, and only a casting roll was used as a take-off means. The peel strength of the lip of the T die is
Using a test piece having the same surface as the lip portion, measurement was performed under the same conditions as described above using TCM500 as a measuring device. Screw: metering type Melting temperature of resin: 260 ° C. Die: T die (lip material: WC, average roughness Ra;
0.14 μm, peel strength: 46 N) ・ Sheet thickness: 100 μm ・ Average roughness Ra of the casting roll surface: 0.05 μm
m ・ Casting roll temperature: 135 ° C

<Evaluation of Film> The surface roughness of the obtained sheet, that is, the maximum roughness Rt and the average roughness Ra, were measured by the method described above (measured length of each sheet was 5 mm; reference length was 0.1 mm).
8m). In measuring the surface roughness,
A stylus type surface roughness meter (Tencor Corp., P-10 type) having a radius of curvature of a needle tip of 5 μm (angle 60 °) was used. The die line on the sheet surface was visually observed to determine the presence or absence thereof.

[0087]

Embodiment 2 As a take-up means, the average roughness Ra of the surface is set to 0.
Using a casting roll having a thickness of 05 μm and a temperature of 143 ° C. and a touch roll having an average surface roughness Ra of 0.14 μm and a temperature of 110 ° C. (touch linear pressure: 47 kgf / cm), a die is formed into a T-die (lip portion). Material: WC, average roughness Ra: 0.14 μm, peel strength: 44N)
A sheet was obtained under the same conditions as in Example 1. Next, the film was evaluated in the same manner as in Example 1.

[0088]

Embodiment 3 As a take-off means, the surface has an average roughness Ra of 0.
Using a casting roll having a temperature of 145 ° C. and a touch roll having an average surface roughness Ra of 0.14 μm and a temperature of 130 ° C. (touch linear pressure: 93 kgf / cm), a die is formed into a T-die (lip portion). Material: WC, average roughness Ra: 0.14 μm, peel strength: 35N)
A sheet was obtained under the same conditions as in Example 1. Next, the film was evaluated in the same manner as in Example 1.

[0089]

Embodiment 4 As a take-off means, the surface has an average roughness Ra of 0.
Using a casting roll having a temperature of 145 ° C. and a touch roll having an average surface roughness Ra of 0.14 μm and a temperature of 110 ° C. (touch linear pressure; 20 kgf / cm), a die is formed into a T-die (lip portion). Material: WC, average roughness Ra: 0.14 μm, peel strength: 46N)
A sheet was obtained under the same conditions as in Example 1. Then, Example 1
The film was evaluated in the same manner as described above.

[0090]

[Comparative Example 1] A die is a T die (lip material: H-Cr,
A sheet was obtained under the same conditions as in Example 1 except that the average roughness Ra was 0.14 μm and the peel strength was 80 N). Next, the film was evaluated in the same manner as in Example 1.

Table 1 shows the evaluation results of the films formed by the above method.

[0092]

[Table 1]

As is apparent from Table 1, no die line was formed in the extruded product made of the cyclic olefin resin of the present invention, and the surface smoothness was extremely reduced when a casting roll and a touch roll were used as the take-up means. An excellent film can be obtained.

[0094]

As described above, the extruded product of the cyclic olefin resin of the present invention has extremely excellent surface smoothness, and thus can be suitably used for optical applications and the like.
Further, by using the production method of the present invention, the production of such a cyclic olefin resin melt-extruded sheet can be performed easily and continuously.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a melt extruded sheet molding apparatus used for producing a cyclic olefin resin extruded product of the present invention.

FIG. 2 is a schematic view showing a T-die used for producing an extrusion molded product of a cyclic olefin resin of the present invention.

FIG. 3 is a schematic diagram illustrating a positional relationship between an exit of a die, a casting roll, and a touch roll.

FIG. 4A is a perspective view of a touch roll in which the diameter of both ends is reduced by providing a step or a taper in the thickness of the touch roll, and FIG. 4B is a perspective view of an elastic body such as rubber on both sides. It is a perspective view of the touch roll provided with the band.

FIG. 5 is a schematic diagram showing a relationship between a casting roll and a touch roll when a touch roll having a flexible roll surface is used.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Melt extrusion film or sheet forming apparatus 2 Pellet-shaped cyclic olefin resin 3 Hopper 4 Cylinder 5 Adapter part 6 Die 7 Cooling roll 8 Sheet or film 9 Winder 10 Extruder 11 Die outlet 12 Casting roll 13 Touch roll 14 Pressing means 15 Flexible sleeve 16 Rubber roll 100 Die body 101 Lip part 102 Adjusting bolt 103 Resin inlet

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C08L 23:02 45:00 47:00 65:00 (72) Inventor Naoki Shinohara Nightlight in Kawasaki-ku, Kawasaki-ku, Kawasaki-ku, Kanagawa 1-2-1 ZEON CORPORATION R & D Center F-term (reference) 4F071 AA14 AA69 BB06 BC01 BC16 4F207 AA03 AA12 AG01 AG08 AG15 AG20 AH35 AH54 KA01 KA11 KA17 KK13 KK64 KL84 KL94

Claims (4)

[Claims] The surface roughness is 0.3 in terms of maximum roughness Rt.
An extruded product made of a cyclic olefin resin having a size of not more than μm. 2. A sheet or film-shaped extruded product made of a cyclic olefin resin having a surface roughness of 0.2 μm or less in terms of average roughness Ra on both surfaces. 3. The method according to claim 1, wherein the cyclic olefin resin is melted, and the molten cyclic olefin resin is extruded through a die having a lip having a peel strength of 75 N or less to form the cyclic olefin resin. A method for producing a cyclic olefin resin extrudate. 4. A method for melting a cyclic olefin resin, extruding a molten cyclic olefin resin through a die, and extruding the cyclic olefin resin so that a nip interval between at least two opposing rolls is constant. The method for producing a cyclic olefin resin extruded product according to claim 1 or 2, wherein the cyclic olefin resin is formed into a sheet or film shape by taking up with a smoothing roll comprising a pressing means provided.