JP2016155327A - Method for manufacturing resin container and resin container - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for producing stably without generating a poor appearance, a container made of a resin excellent in transparency, and hardly adsorbing a protein or the like on an inner wall.SOLUTION: There is provided a production method of a container made of a resin having a step for molding a molding material containing a cyclic olefin resin by using a mold including a core and a cavity. In the production method of the container made of the resin, a surface roughness (Ra) of the core is 0.02-0.20 μm. A container made of a resin obtained by the method is also provided.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a method for stably producing a resin container that is excellent in transparency and hardly adsorbs protein or the like to an inner wall without causing poor appearance, and a resin container obtained by this method.

In recent years, cyclic olefin resins are widely used as molding materials for resin molded products such as pharmaceutical containers because they are excellent in transparency, low moisture absorption, heat resistance, chemical resistance, and the like.
For example, Patent Document 1 describes a medical device made of a thermoplastic norbornene resin. Specific examples of the medical device include a cylindrical container and a syringe syringe manufactured by an injection molding method.

Injection molding is usually performed by the following method using an injection molding machine (for example, an injection molding machine shown in FIG. 1) having an injection unit and a mold.
The injection molding machine (1) shown in FIG. 1 has an injection unit (2) and a mold (3). The mold (3) has a cavity (4) and a core (5), and a space (product part) (6) exists between the cavity (4) and the core (5).
When manufacturing a resin molded product, first, after a molding material is put into the cylinder (8) from the hopper (7), the molding material is heated and plasticized. Next, by advancing the screw (9), the molten resin (plasticized molding material) is injected and injected from the nozzle (10) into the mold (3) that has been clamped. After the molten resin is filled into the space (product part) (6) of the mold (3), the molten resin is cooled and solidified. Next, the mold (3) is opened and the resin molded product is taken out.
When the mold (3) is opened, the core (5) and the resin molded product (11) are usually integrated as shown in FIG. 2 (A). Then, the core (5) and the resin molded product (11) are separated using a protruding pin, a plate, air, or the like (not shown) [FIG. 2 (B)].

The container made of cyclic olefin resin can be manufactured using the injection molding method as described above.
However, when a resin container is produced using a molding material containing a cyclic olefin resin, the core and the resin container tend to be in close contact with each other. When these are separated [that is, the core (5) in the above description] When the resin molded product (11) is separated], it takes time, or the inner wall of the container may be scratched, resulting in a poor appearance of the resin container. Since scratches on the inner wall of the container may interfere with the quality confirmation of the contents by visual recognition, there has been a demand for a method for stably producing a resin container without causing such appearance defects.

In relation to the present invention, Patent Document 2 describes a method for manufacturing a prefilled syringe outer cylinder. In this document, a prefilled syringe outer cylinder having high transparency is obtained by injection molding of a cyclic olefin resin composition using an injection mold having a core surface roughness (Rz) of 50 μm or less. It is described that
However, the resin container obtained using the core having the surface roughness described in Patent Document 2 has a rough inner wall surface, and proteins and the like are easily adsorbed to the inner wall of the container. It was not suitable as.

JP-A-5-317411 JP 2013-132393 A

  The present invention has been made in view of the above-described prior art, and is a method for stably producing a resin container that is excellent in transparency and hardly adsorbs protein or the like to the inner wall without causing poor appearance. And it aims at providing the resin-made containers obtained by this method.

  In order to solve the above-mentioned problems, the present inventors have intensively studied a mold used when manufacturing a resin container. As a result, by molding a molding material containing a cyclic olefin resin using a mold having a core surface roughness (Ra) within a specific range, the core is excellent in transparency, and protein and the like are on the inner wall. The present inventors have found that a resin container that is not easily adsorbed by the resin can be stably produced without causing an appearance defect, and the present invention has been completed.

Thus, according to the present invention, the following [1] to [4] resin container manufacturing method and [5] resin container are provided.
[1] A method for producing a resin container, comprising a step of molding a molding material containing a cyclic olefin resin using a mold having a core and a cavity, the surface roughness (Ra) of the core Is 0.02 to 0.20 μm.
[2] The method for producing a resin container according to [1], wherein the core is obtained by roughening a core having a surface roughness (Ra) of less than 0.02 μm by a projection treatment method.
[3] The method for producing a resin container according to [2], wherein an average particle diameter of the projection material used for the projection treatment method is 10 to 30 μm.
[4] The method for producing a resin container according to any one of [1] to [3], wherein the resin container is an outer cylinder for a prefilled syringe.
[5] A resin container obtained by the production method according to the above [1] to [4].

According to the present invention, a method for stably producing a resin container that is excellent in transparency and hardly adsorbs protein or the like to the inner wall without causing poor appearance, and a resin container obtained by this method are provided. Provided.
Since the resin container obtained by the method of the present invention is excellent in transparency, hardly adsorbs proteins and the like on the inner wall, and has a good appearance, it is suitably used as a pharmaceutical container such as an outer cylinder for prefilled syringes.

It is a schematic diagram showing a general injection molding machine. It is a schematic diagram showing the separation process of a core and a resin molded product. It is a schematic diagram showing the cylindrical shape molded article manufactured in the Example.

  The method for producing a resin container of the present invention includes a step of molding a molding material containing a cyclic olefin resin using a mold having a core and a cavity, and the surface roughness of the core (Ra ) Is 0.02 to 0.20 μm.

〔Mold〕
The metal mold | die used for this invention is equipped with a core and a cavity. As this mold, a mold used for a resin container used in a normal injection molding method or the like can be used without particular limitation, except that the surface roughness (Ra) of the core is specified. Therefore, the shape, size, material and the like of the core and cavity are not particularly limited.

The surface roughness (Ra) of the core is 0.02 to 0.20 μm, preferably 0.02 to 0.10 μm.
When the surface roughness (Ra) of the core is less than 0.02 μm, there is a tendency to be inferior in releasability when separating the core and the resin container, so that the inner wall of the resin container is scratched, Productivity decreases. On the other hand, when the surface roughness (Ra) of the core exceeds 0.20 μm, the transparency of the resin container tends to decrease, or proteins or the like tend to be adsorbed on the inner wall of the resin container.
The surface roughness (Ra) of the cavity is not particularly limited, but is usually 0.01 to 0.50 μm, preferably 0.10 to 0.40 μm.
In the present invention, the surface roughness (Ra) can be measured using a laser microscope.

  The manufacturing method of the core used for this invention is not specifically limited. For example, a method of polishing a core having a surface roughness (Ra) of more than 0.20 μm, a method of roughening a core having a surface roughness (Ra) of less than 0.02 μm by a projection processing method, and the like. The latter method is preferable because the core used in the present invention can be obtained well. The former polishing method is not particularly limited, and a conventionally known method such as using diamond abrasive grains can be employed.

  In the latter method, first, the surface roughness (Ra) of the core is made less than 0.02 μm. The method for making the surface roughness (Ra) of the core less than 0.02 μm is not particularly limited. For example, the surface roughness (Ra) of the core can be made less than 0.02 μm by a conventionally known method such as using diamond abrasive grains. Note that this operation can be omitted when the core has a surface roughness (Ra) of less than 0.02 μm.

  Projection processing methods are high-speed projection of projection materials onto the target, such as shot blasting for surface grinding and removal of deposits, shot peening for the purpose of imparting compressive residual stress, work hardening by plastic deformation, etc. In this way, the surface of the object is modified. However, when aiming at these effects, a relatively large projecting material is usually used, but when aiming at roughening of a smooth core, a smaller projecting material is used as described later.

Although it does not specifically limit as a projection material, Alumina particle, silicon carbide particle, etc. are mentioned. The average particle diameter of the projection material is usually 10 to 30 μm, preferably 10 to 20 μm. The average particle diameter of the projection material can be determined using a laser diffraction particle size distribution apparatus.
The particle size distribution index (D90 / D10) of the projection material is not particularly limited, but is preferably 2.0 or less, more preferably 1.5 or less.
Although the projection pressure at the time of projecting a projection material is not specifically limited, Usually, it is 0.02-0.30 MPa, Preferably it is 0.02-0.10 MPa.
The time for projecting the projection material is usually 5 to 120 seconds, preferably 5 to 60 seconds.
The value of the surface roughness (Ra) can be adjusted by appropriately adjusting the average particle diameter, the projection pressure, and the projection time of the projection material.

[Cyclic olefin resin]
The cyclic olefin resin constituting the molding material used in the present invention is a polymer having an alicyclic structure in the molecule, and a polymer obtained by performing a polymerization reaction using a cyclic olefin as a monomer or Its hydride.
Examples of the alicyclic structure of the cyclic olefin resin include a cycloalkane structure and a cycloalkene structure. Among these, a cycloalkane structure is preferable because a resin container excellent in transparency, light resistance, durability, and the like can be easily obtained. The number of carbon atoms constituting the alicyclic structure is not particularly limited, but is usually 4 to 30, preferably 5 to 20, and more preferably 5 to 15.

  The weight average molecular weight (Mw) of the cyclic olefin resin to be used is preferably 20,000 to 100,000, more preferably 25,000 to 50,000. If the weight average molecular weight (Mw) of the cyclic olefin resin is too small, the strength of the resin container may be reduced. On the other hand, if the weight average molecular weight (Mw) of the cyclic olefin resin is too large, the moldability of the molding material may be lowered.

Although molecular weight distribution (Mw / Mn) of cyclic olefin resin is not specifically limited, Preferably it is 1-5, More preferably, it is 1-4.
When the molecular weight distribution of the cyclic olefin resin is within the above range, a resin container having sufficient mechanical strength can be obtained.
The weight average molecular weight (Mw) and the number average molecular weight (Mn) of the cyclic olefin resin are standard polyisoprene conversion values by gel permeation chromatography (GPC) using cyclohexane as an eluent.

The cyclic olefin resin used in the present invention includes a ring-opening polymer of a cyclic olefin monomer (hereinafter sometimes referred to as “polymer (α)”), a hydride thereof, and a cyclic olefin monomer. Examples thereof include a polymer (hereinafter sometimes referred to as “polymer (β)”) and a hydride thereof.
As will be described later, the cyclic olefin resin is preferably a hydride of the polymer (α) because it is excellent in various properties and is easy to obtain a target resin container.

(1) Polymer (α) and its hydride The cyclic olefin monomer used for the production of the polymer (α) and its hydride has a ring structure formed of carbon atoms, and carbon is contained in the ring. -A compound having a carbon double bond. Specific examples include norbornene monomers. Moreover, when a polymer ((alpha)) is a copolymer, a monocyclic cyclic olefin can also be used as a cyclic olefin monomer.

The norbornene monomer is a monomer containing a norbornene ring.
The norbornene-based monomer includes bicyclo [2.2.1] hept-2-ene (common name: norbornene), 5-ethylidene-bicyclo [2.2.1] hept-2-ene (common name: ethylidene). Norbornene) and derivatives thereof (those having a substituent in the ring);
Tricyclic monomers such as tricyclo [4.3.0.1 ^2,5 ] deca-3,7-diene (common name: dicyclopentadiene) and derivatives thereof;
7,8-tricyclo [4.3.0.1 ^{2, 5]} dec-3-ene (common name: methanolate tetrahydrofluorene, tetracyclo ^[7.4.0.0 2,7 ^{.1 10,13]} Trideca-2,4,6,11-tetraene) and its derivatives, tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene (common name: tetracyclododecene), 8-ethylidenetetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene and tetracyclic monomers such as derivatives thereof; and the like.

  Examples of substituents for these monomers include alkyl groups such as methyl and ethyl groups; alkenyl groups such as vinyl groups; alkylidene groups such as ethylidene groups and propane-2-ylidene groups; aryl groups such as phenyl groups; Group; acid anhydride group; carboxyl group; alkoxycarbonyl group such as methoxycarbonyl group; and the like.

  Examples of the monocyclic olefin include cyclomonoolefins such as cyclobutene, cyclopentene, methylcyclopentene, cyclohexene, methylcyclohexene, cycloheptene, and cyclooctene; cyclohexadiene, methylcyclohexadiene, cyclooctadiene, methylcyclooctadiene, phenylcyclooctadiene Cyclic diolefins such as; and the like.

These cyclic olefin monomers can be used alone or in combination of two or more.
When two or more cyclic olefin monomers are used, the polymer (α) may be a block copolymer or a random copolymer.
Among these, as the cyclic olefin monomer, tricyclo [4.3.0.1 ^2,5 ] deca-3,7-diene, tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene, tetracyclo [7.4.0.0 ^2,7 . 1 ^{10, 13]} trideca -2,4,6,11- tetraene is preferable.

The polymer (α) can be produced according to a known method using a metathesis polymerization catalyst.
The metathesis polymerization catalyst is not particularly limited and known ones are used. As a metathesis polymerization catalyst, a catalyst system comprising a metal halide, nitrate or acetylacetone compound selected from ruthenium, rhodium, palladium, osmium, iridium and platinum and a reducing agent; from titanium, vanadium, zirconium, tungsten and molybdenum A catalyst system comprising a selected metal halide or acetylacetone compound and a co-catalyst organoaluminum compound; a Schrock-type or Grubbs-type living ring-opening metathesis polymerization catalyst (JP-A-7-179575, J. Am. Chem. Soc., 1986, 108, p.733, J. Am.Chem.Soc., 1993, 115, p.9858, and J.Am.Chem.Soc., 1996, 118, p.100); Etc.
These metathesis polymerization catalysts can be used alone or in combination of two or more.

  The amount of the metathesis polymerization catalyst used may be appropriately selected depending on the polymerization conditions and the like, but is usually 0.000001 to 0.1 mol, preferably 0.00001 to 0.01 with respect to 1 mol of the cyclic olefin monomer. Is a mole.

When performing ring-opening polymerization of a cyclic olefin monomer, a linear α-olefin having 4 to 40 carbon atoms such as 1-butene, 1-hexene, 1-decene and the like can be used as a molecular weight regulator.
The addition amount of the linear α-olefin is usually 0.001 to 0.030 mol, preferably 0.003 to 0.020 mol, more preferably 0.005 to 0, per 1 mol of the cyclic olefin monomer. .015 mole.

  The ring-opening polymerization of the cyclic olefin monomer can be performed in an organic solvent. The organic solvent is not particularly limited as long as it is inert to the polymerization reaction. For example, aromatic hydrocarbon solvents such as benzene, toluene and xylene; aliphatic hydrocarbon solvents such as n-pentane, n-hexane and n-heptane; alicyclic carbonization such as cyclohexane, methylcyclohexane, decalin and bicyclononane And hydrogenated solvents; halogenated hydrocarbon solvents such as dichloroethane, chlorobenzene, dichlorobenzene, and trichlorobenzene; and mixed solvents composed of two or more of these.

  Although superposition | polymerization temperature is not specifically limited, Usually, -50-250 degreeC, Preferably it is -30-200 degreeC, More preferably, it is -20-150 degreeC. The polymerization time is appropriately selected depending on the polymerization conditions, but is usually 30 minutes to 20 hours, preferably 1 to 10 hours.

A hydride of the polymer (α) can be obtained by subjecting the polymer (α) obtained by the above method to a hydrogenation reaction.
The hydrogenation reaction of the polymer (α) can be performed by bringing the polymer (α) into contact with hydrogen in the presence of a hydrogenation catalyst according to a conventional method.

The hydrogenation catalyst may be a homogeneous catalyst or a heterogeneous catalyst.
The homogeneous catalyst can be easily dispersed in the hydrogenation reaction solution, so that the amount of catalyst added can be suppressed. In addition, the polymer (α) and its hydride are not easily decomposed or gelled because they have sufficient activity even without high temperature and pressure. For this reason, it is preferable to use a homogeneous catalyst from the viewpoint of cost and product quality.
On the other hand, since the heterogeneous catalyst exhibits particularly excellent activity under high temperature and high pressure, the polymer (α) can be hydrogenated in a short time. Further, the catalyst residue can be efficiently removed after the hydrogenation reaction.

  As homogeneous catalysts, Wilkinson complex [chlorotris (triphenylphosphine) rhodium (I)]; cobalt acetate / triethylaluminum, nickel acetylacetonate / triisobutylaluminum, titanocene dichloride / n-butyllithium, zirconocene dichloride / sec-butyl A catalyst comprising a combination of a transition metal compound and an alkyl metal compound, such as a combination of lithium, tetrabutoxytitanate / dimethylmagnesium, and the like.

  Examples of the heterogeneous catalyst include those in which a metal such as Ni, Pd, Pt, Ru, and Rh is supported on a carrier. In particular, when reducing the amount of impurities in the hydride obtained, it is preferable to use an adsorbent such as alumina or diatomaceous earth as the carrier.

The hydrogenation reaction is usually performed in an organic solvent. The organic solvent is not particularly limited as long as it is inert to the hydrogenation reaction. As the organic solvent, a hydrocarbon solvent is usually used because it easily dissolves the hydride produced. Examples of the hydrocarbon solvent include aromatic hydrocarbon solvents such as benzene, toluene and xylene; aliphatic hydrocarbon solvents such as n-pentane, n-hexane and n-heptane; cyclohexane, methylcyclohexane, decalin, bicyclononane and the like. Alicyclic hydrocarbon-based solvents; and the like.
These organic solvents can be used alone or in combination of two or more. In general, the solvent used in the ring-opening polymerization reaction is also suitable as a solvent for the hydrogenation reaction. Therefore, after adding a hydrogenation catalyst to the ring-opening polymerization reaction solution, it can be used for the hydrogenation reaction.

  The hydrogenation rate varies depending on the type of hydrogenation catalyst and the reaction temperature. Therefore, when the polymer (α) has an aromatic ring, the residual ratio of the aromatic ring can be controlled by selecting a hydrogenation catalyst, adjusting the reaction temperature, or the like. For example, in order to leave an unsaturated bond in the aromatic ring more than a certain amount, control such as lowering the reaction temperature, lowering the hydrogen pressure, or shortening the reaction time may be performed.

  After completion of the hydrogenation reaction, the catalyst residue can be removed by performing a treatment such as centrifugation or filtration. If necessary, a catalyst deactivator such as water or alcohol may be used, or an adsorbent such as activated clay or alumina may be added.

(2) Polymer (β) and its hydride The cyclic olefin monomer used for the synthesis of polymer (β) and its hydride was shown as the cyclic olefin monomer used for the synthesis of polymer (α). The thing similar to a thing is mentioned.
In the synthesis of the polymer (β), other monomers copolymerizable with the cyclic olefin monomer can be used as the monomer.
Examples of other monomers include α-olefins having 2 to 20 carbon atoms such as ethylene, propylene, 1-butene, 1-pentene and 1-hexene; aromatic vinyl compounds such as styrene and α-methylstyrene; Non-conjugated dienes such as 4-hexadiene, 4-methyl-1,4-hexadiene, 5-methyl-1,4-hexadiene, 1,7-octadiene; and the like. Among these, α-olefin is preferable and ethylene is more preferable.
Other monomers can be used alone or in combination of two or more.

  In the case of addition copolymerization of a cyclic olefin monomer and another monomer, the ratio of the amount used of the cyclic olefin monomer and the other monomer is a weight ratio (cyclic olefin monomer: other The monomer is usually 30:70 to 99: 1, preferably 50:50 to 97: 3, and more preferably 70:30 to 95: 5.

  When two or more cyclic olefin monomers are used, or when a cyclic olefin monomer and other monomers are used, the polymer (β) may be a block copolymer or a random copolymer. It may be a coalescence.

The polymer (β) can be synthesized according to a known method using an addition polymerization catalyst.
Examples of addition polymerization catalysts include vanadium catalysts formed from vanadium compounds and organoaluminum compounds, titanium catalysts formed from titanium compounds and organoaluminum compounds, zirconium catalysts formed from zirconium complexes and aluminoxanes, and the like. It is done.
These addition polymerization catalysts can be used singly or in combination of two or more. The addition amount of the addition polymerization catalyst may be appropriately selected depending on the polymerization conditions and the like, but is usually 0.000001 to 0.1 mol, preferably 0.00001 to 0.01 mol with respect to 1 mol of the monomer. is there.

  The addition polymerization of the cyclic olefin monomer is usually performed in an organic solvent. Examples of the organic solvent include the same solvents as those used for the ring-opening polymerization of the cyclic olefin monomer.

  The polymerization temperature is usually −50 to 250 ° C., preferably −30 to 200 ° C., more preferably −20 to 150 ° C. The polymerization time is appropriately selected depending on the polymerization conditions, but is usually 30 minutes to 20 hours, preferably 1 to 10 hours.

By subjecting the polymer (β) obtained by the above method to a hydrogenation reaction, a hydride of the polymer (β) can be obtained.
The hydrogenation reaction of the polymer (β) can be carried out by the same method as that shown above as the method for hydrogenating the polymer (α).

[Molding material]
The molding material used in the present invention contains the cyclic olefin resin. The molding material may contain other components such as a resin component other than the cyclic olefin resin and additives as long as the effects of the present invention are not impaired.

Resin components other than cyclic olefin resins (hereinafter sometimes referred to as “other resin components”) include styrene / butadiene block copolymers, styrene / butadiene / styrene / block copolymers, styrene / isoprene / block copolymers. Examples thereof include styrene polymers such as polymers, styrene / isoprene / styrene block copolymers, hydrogenated products thereof, and styrene / butadiene / random copolymers.
When the molding material used for this invention contains another resin component, the content is 0.1-100 weight part normally with respect to 100 weight part of cyclic olefin resin, Preferably it is 1-50 weight part. is there.

Examples of the additive include an antioxidant, an ultraviolet absorber, a light stabilizer, a near infrared absorber, a plasticizer, an antistatic agent, and an acid supplement.
Examples of the antioxidant include phenolic antioxidants, phosphorus antioxidants, sulfur antioxidants, and the like.

  Examples of phenolic antioxidants include 3,5-di-t-butyl-4-hydroxytoluene, dibutylhydroxytoluene, 2,2′-methylenebis (6-t-butyl-4-methylphenol), 4,4 ′. -Butylidenebis (3-t-butyl-3-methylphenol), 4,4'-thiobis (6-t-butyl-3-methylphenol), α-tocophenol, 2,2,4-trimethyl-6-hydroxy -7-t-butylchroman, tetrakis [methylene-3- (3 ′, 5′-di-t-butyl-4′-hydroxyphenyl) propionate] methane, [pentaerythritol tetrakis [3- (3,5-di -T-butyl-4-hydroxyphenyl) propionate]] and the like.

  Examples of phosphorus antioxidants include distearyl pentaerythritol diphosphite, bis (2,4-ditertiarybutylphenyl) pentaerythritol diphosphite, tris (2,4-ditertiarybutylphenyl) phosphite, tetrakis (2 , 4-ditertiary butylphenyl) 4,4′-biphenyl diphosphite, trinonylphenyl phosphite and the like.

  Examples of sulfur-based antioxidants include distearyl thiodipropionate and dilauryl thiodipropionate.

Examples of the UV absorber include benzotriazole UV absorbers, bezoate UV absorbers, benzophenone UV absorbers, acrylate UV absorbers, and metal complex UV absorbers.
Examples of the light stabilizer include hindered amine light stabilizers.

Near-infrared absorbers are cyanine-based near-infrared absorbers; pyrylium-based infrared absorbers; squarylium-based near-infrared absorbers; croconium-based infrared absorbers; azulenium-based near-infrared absorbers; Examples include near infrared absorbers; naphthoquinone near infrared absorbers; anthraquinone near infrared absorbers; indophenol near infrared absorbers;
Examples of the plasticizer include a phosphoric acid triester plasticizer, a fatty acid monobasic acid ester plasticizer, a dihydric alcohol ester plasticizer, and an oxyacid ester plasticizer.
Examples of the antistatic agent include fatty acid esters of polyhydric alcohols.
Examples of the acid supplement include magnesium oxide and zinc stearate.

  The content of these components can be appropriately determined according to the purpose. Content is 0.001-5 weight part normally with respect to 100 weight part of cyclic olefin resin, Preferably it is the range of 0.01-1 weight part.

A molding material can be obtained by mixing each component according to a conventional method. Examples of the mixing method include a method of mixing each component in an appropriate solvent and a method of kneading in a molten state.
Kneading can be performed using a melt kneader such as a single screw extruder, a twin screw extruder, a Banbury mixer, a kneader, or a feeder ruder. The kneading temperature is preferably 200 to 400 ° C, more preferably 240 to 350 ° C. In kneading, the components may be added together and kneaded, or may be kneaded while adding in several times.
After kneading, it can be pelletized by extruding into a rod shape and cutting into an appropriate length with a strand cutter according to a conventional method.

[Method for producing resin container and resin container]
The method for producing a resin container of the present invention includes a step of molding the molding material using the mold.
The molding method is not particularly limited, and examples thereof include an injection molding method, an injection blow molding method (cold parison method), and a thermoforming method. Among these, the injection molding method is preferable because the target resin container can be efficiently manufactured.

  When manufacturing a resin container using the injection molding method, the molding material is usually put into a hopper of an injection molding machine, plasticized in a high-temperature cylinder, and then molten resin (plasticized molding material) ) Is injected into the mold from the nozzle. A resin container is formed by cooling and solidifying the molten resin in the mold.

  The cylinder temperature is appropriately selected in the range of usually 200 to 400 ° C, preferably 200 to 350 ° C, more preferably 250 to 310 ° C. If the cylinder temperature is excessively low, the fluidity of the molten resin is lowered, and there is a risk that sinks or strains may occur in the resin container. On the other hand, if the cylinder temperature is excessively high, silver streaks due to thermal decomposition of the molding material may occur, or the resin container may turn yellow.

The injection speed when the molten resin is injected from the cylinder to the mold is preferably 1 to 1,000 cm ³ / sec. When the injection speed is in this range, it becomes easy to obtain a resin container having an excellent appearance.
The injection pressure when injecting the molten resin from the cylinder to the mold is not particularly limited, and may be set as appropriate in consideration of the type of the mold and the fluidity of the molten resin. The injection pressure is usually 50 to 250 MPa.

  The mold temperature is usually lower than the glass transition temperature (Tg) of the cyclic olefin resin in the molding material, preferably 0 to 50 ° C lower than Tg, more preferably 5 to 30 ° C lower than Tg. The temperature is low. When the mold temperature is within this range, a resin container with less distortion is easily obtained.

After the molten resin is cooled and solidified in the mold, the mold is opened and the resin container is taken out. Normally, when the mold is opened, the core and the resin container are integrated, so that the core and the resin container are separated by a known method using a protruding pin, a plate, air, or the like.
Since the manufacturing method of the present invention uses the mold, even when a resin container is manufactured using a molding material containing a cyclic olefin resin, scratches are caused on the inner wall of the container. And the core and the resin container can be separated efficiently. Since this feature is fully utilized, the method of the present invention is suitably used when manufacturing an elongated resin container such as an outer cylinder for a prefilled syringe.

The resin container of the present invention is obtained by the above production method, has excellent transparency, hardly adsorbs proteins and the like on the inner wall, and has a good appearance. Therefore, the resin container of the present invention is suitably used as a pharmaceutical container or a member constituting the same.
Pharmaceutical containers include infusion containers and infusion kit containers; eye drops containers; pure water containers; sampling tubes for blood analysis; blood collection tubes; sample containers; analysis containers such as UV test cells; Sterilization containers for medical instruments such as gauze and contact lenses; medical instruments such as disposable syringes and prefilled syringes; laboratory instruments such as beakers, vials, ampoules, test tubes and flasks; and housings for artificial organs. Among these, a chemical container that is sterilized after being filled with a chemical such as a prefilled syringe is preferable.

  Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples. The present invention is not limited to these examples. In the following, “parts” and “%” are based on weight unless otherwise specified.

In Examples and Comparative Examples, various physical properties are measured as follows.
(1) Weight average molecular weight (Mw) and number average molecular weight (Mn)
The weight average molecular weight (Mw) and the number average molecular weight (Mn) of the polymer after the hydrogenation reaction were determined by performing gel permeation chromatography (GPC) using cyclohexane as an eluent at 40 ° C., and as a standard polyisoprene conversion value. Asked.
Measuring device: HLC8120GPC manufactured by Tosoh Corporation
Column: TOSGE G5000HXL, TSKgel G4000HXL, TSKgel G2000HXL, manufactured by Tosoh Corporation, were used in series.
Standard polyisoprene: manufactured by Tosoh Corporation, standard polyisoprene, Mw = 602, 1390, 3920, 8050, 13800, 22700, 58800, 71300, 109000, 280000
Flow rate: 1.0 ml / min Sample injection volume: 100 μml
Column temperature: 40 ° C

(2) Hydrogenation rate ¹ H-NMR measurement was performed using deuterated chloroform as a solvent, and the hydrogenation rate in the hydrogenation reaction was calculated.
(3) Glass transition temperature (Tg)
The glass transition temperature (Tg) was measured based on JIS K 6911 using a differential scanning calorimeter (DSC6220S11, manufactured by Nanotechnology).
(4) Melt mass flow rate (MFR)
The melt mass flow rate (MFR) was measured at 280 ° C. and a 2.16 kg load according to JIS K 7210.

(5) Core surface roughness (Ra)
Using a laser microscope (manufactured by Keyence Corporation, product name “VK-9700”), the surface roughness of the core (arithmetic average roughness: Ra) was measured in an observation field of 6,656 μm ² .

(6) Releasability In the examples and comparative examples, when separating the cylindrical resin molded body from the core, the load current of the ejector motor of the injection molding machine (product name “ROBOSHOT S2000i-50A” manufactured by FUNUC) The value (%) [value as a load when the rated capacity value of the motor is assumed to be 100%] was measured, and the release property of the resin molded body was evaluated. Here, when the load current value is smaller than 35%, it can be evaluated that the releasability is good.

(7) Transparency About the cylindrical resin moldings obtained in Examples and Comparative Examples, light transmittance at a wavelength of 405 nm using an ultraviolet-visible spectrophotometer (manufactured by JASCO Corporation, product name “V-760”). Was measured (optical path length 2.6 mmt). Here, when the light transmittance was larger than 75%, it was judged that the transparency was high.

(8) Protein adsorption property The cylindrical resin molded bodies obtained in Examples and Comparative Examples are used as syringe outer cylinders, and an aqueous solution of BSA (bovine serum albumin) (concentration 100 μg / ml, pH 7) is contained therein. Put in the lid. This was allowed to stand at 4 ° C. for 1 week, and then this aqueous solution was used as a sample solution for high performance liquid chromatography (manufactured by Agilent, product name “HP1100”), and the amount of BSA was quantified from the absorbance at 220 nm. Here, it was judged that the low adsorptivity was excellent when the BSA reduction amount was less than 10%.

[Production Example 1]
In a nitrogen atmosphere, at room temperature, 500 parts of dehydrated cyclohexane, 0.82 part of 1-hexene, 0.15 part of dibutyl ether and 0.30 part of triisobutylaluminum were placed in the reactor, and the whole volume was mixed. And 76 parts of tricyclo [4.3.0.1 ^2,5 ] deca-3,7-diene (common name: dicyclopentadiene, hereinafter abbreviated as “DCP”), tetracyclo [7.4.0. 0.0 ^2,7 . 1 ^10,13] trideca -2,4,6,11- tetraene (hereinafter referred to as "MTF") 54 parts, tetracyclo [4.4.0.1 ^{2, 5.} 1 ^7,10 ] A norbornene-based monomer mixture consisting of 70 parts of dodec-3-ene (hereinafter abbreviated as “TCD”) and 40 parts of a 0.7% toluene solution of tungsten hexachloride are continuously added over 2 hours. It was dropped and a ring-opening polymerization reaction was performed.
Next, 1.06 part of butyl glycidyl ether and 0.52 part of isopropyl alcohol were added to the reaction solution to stop the ring-opening polymerization reaction.

To 100 parts of the obtained reaction solution, 270 parts of cyclohexane was added, and further 5 parts of a nickel-alumina catalyst (manufactured by JGC Chemical Co., Ltd.) was added as a hydrogenation catalyst, and hydrogen was introduced into the system until the pressure became 5 MPa. Subsequently, a hydrogenation reaction was carried out at 200 ° C. for 4 hours under stirring to obtain a reaction solution containing 20% of a DCP / MTF / TCD ring-opening polymer hydrogenated product. The hydrogenation catalyst was filtered off from the resulting reaction solution.
The reaction solution was then charged with 0.5 parts of antioxidant: pentaerythritol tetrakis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate] (Ciba. Specialty Chemical Co., Ltd., product name “Irganox (registered trademark) 1010”) was added and dissolved.
Next, using a cylindrical concentrating dryer (manufactured by Hitachi, Ltd.), cyclohexane and other volatile components as solvents are removed from this solution under conditions of a temperature of 270 ° C. and a pressure of 1 kPa or less. The molten resin was extruded into a strand form from a directly connected die, pelletized after cooling to obtain a ring-opening copolymer hydrogenated pellet (A).
The resulting ring-opening copolymer hydrogenated product has a weight average molecular weight of 33,000, a molecular weight distribution (Mw / Mn) of 2.5, a hydrogenation rate of 99.5%, and a glass transition temperature of 135 ° C. The MFR was 16.1 g / 10 min.

[Production Example 2]
In a nitrogen atmosphere at room temperature, 250 parts of dehydrated cyclohexane, 0.84 part of 1-hexene, 0.06 part of dibutyl ether and 0.11 part of triisobutylaluminum were placed in the reactor, and the whole volume was mixed. And 85 parts of tricyclo [4.3.0.1 ^2,5 ] dec-3-ene (hereinafter DCP), 8-ethyl-tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene (hereinafter referred to as ETD) 15 parts and 15 parts 0.7% toluene solution of tungsten hexachloride were continuously added over 2 hours to carry out a ring-opening polymerization reaction. The polymerization conversion of this reaction was 100%.
The reaction solution was transferred to a pressure-resistant hydrogenation reactor, and 5 parts of a diatomaceous earth-supported nickel catalyst (manufactured by Nissan Gardler; G-96D, nickel support rate of 58%) and 100 parts of cyclohexane were added. The hydrogenation reaction was performed for 8 hours under the condition of a pressure of 4.4 MPa. The obtained reaction solution was subjected to pressure filtration (Hunda filter, manufactured by Ishikawajima-Harima Heavy Industries Co., Ltd.) at a pressure of 0.25 MPa using Radiolight # 500 as a filter bed to remove the hydrogenation catalyst and obtain a colorless and transparent solution. It was. To this solution was added 0.3 parts of antioxidant: pentaerythritol tetrakis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate] (Irganox 1010, Ciba Geigy) per 100 parts of the hydrogenated product. Was added to dissolve it. Next, the solution is filtered using a Zeta Plus filter 30H (pore size: 0.5 to 1 μm, manufactured by Kyunofilter) and a metal fiber filter (pore size: 0.4 μm, manufactured by Nichidai) to form a fine solid. Minutes removed.
Next, using a cylindrical concentrating dryer (manufactured by Hitachi, Ltd.), cyclohexane and other volatile components as solvents are removed from this solution under conditions of a temperature of 270 ° C. and a pressure of 1 kPa or less. The molten resin was extruded into a strand form from a directly connected die, and pelletized after cooling to obtain pellets (B) of the ring-opening copolymer hydrogenated product.
The resulting hydrogenated ring-opening copolymer had a weight average molecular weight (Mw) of 30,000, a molecular weight distribution (Mw / Mn) of 2.5, a hydrogenation rate of 99.5%, and a glass transition point of 105 ° C. , MFR was 20.5 g / 10 min.

[Production Example 3]
960 parts of toluene, 220 parts of 2-norbornene, and 0.166 part of 1-hexene were placed in a 1 liter tank reactor equipped with a stirrer, the inside of which was replaced with nitrogen, and the whole volume was stirred while stirring at a rotational speed of 300 to 350 rpm. The temperature was raised to ° C.
On the other hand, 23.5 parts of toluene, 0.044 parts of rac-ethylenebis (1-indenyl) zirconium dichloride, methylaluminoxane 9.0% toluene solution (manufactured by Tosoh Finechem: TMAO-200 series) 6.22 parts A catalyst solution was obtained by mixing in a glass container.
The obtained catalyst solution was added into the reactor, and then 0.08 MPa ethylene gas was immediately introduced into the liquid phase to initiate polymerization. The position of the ethylene outlet is such that the ratio (b) / (a) between the distance (a) between the bottom of the reactor and the liquid level and the distance (b) between the ethylene outlet and the liquid level is 0.60. It is. When the ethylene gas was consumed, the ethylene gas was automatically supplied to keep the pressure of the ethylene gas constant. After 30 minutes, the introduction of ethylene gas was stopped, the pressure was released, and then 5 parts of methanol was added to stop the polymerization reaction.
This solution was filtered with Radiolite # 800, and the obtained filtrate was poured into isopropanol containing 0.05% hydrochloric acid to precipitate a polymer. The precipitated polymer was collected, washed, dried under reduced pressure at 100 ° C. for 15 hours, then extruded into a strand shape in a molten state, cooled, and pelletized to obtain an ethylene-2-norbornene copolymer pellet (C). .
When the weight average molecular weight (Mw) and molecular weight distribution (Mw / Mn) of the obtained ethylene-2-norbornene copolymer were measured, they were Mw = 68,000 and Mw / Mn = 2.2. The glass transition temperature was 130 ° C.

[Example 1]
The surface roughness (Ra) of the core of a mold (a mold including a core and a cavity) for a cylindrical molded product [(A) front view, (B) side view] having the shape shown in FIG. Polishing was performed until the thickness became 0.01 μm or less. Subsequently, the projection process was performed on the following conditions, and the surface of this core was roughened. The surface roughness (Ra) of the core after the treatment was 0.02 μm.

(Projection processing conditions)
Projection material: spherical alumina powder, average particle size 20 μm
Projection pressure: 0.03 MPa

The pellet (A) was injection molded (molding temperature 300 ° C., injection pressure 150 MPa) using an injection molding machine (manufactured by FUNUC, product name “ROBOSHOT S2000i-50A”) provided with the roughened mold. The mold temperature was 100 ° C., the holding time in the mold was 20 seconds, and the ejector speed was 30 mm / second.
About this resin molding, mold release property, transparency, and protein adsorptivity were evaluated. The evaluation results are shown in Table 1.

[Example 2]
A resin molded body was obtained in the same manner as in Example 1, except that the projection pressure was changed to 0.10 MPa and the surface roughness (Ra) of the core was changed to 0.05 μm. About this resin molding, mold release property, transparency, and protein adsorptivity were evaluated. The evaluation results are shown in Table 1.

[Example 3]
A resin molded body was obtained in the same manner as in Example 1, except that the projection pressure was changed to 0.30 MPa and the surface roughness (Ra) of the core was changed to 0.18 μm. About this resin molding, mold release property, transparency, and protein adsorptivity were evaluated. The evaluation results are shown in Table 1.

[Example 4]
Resin molding in the same manner as in Example 1 except that the pellet (B) was used instead of the pellet (A) in Example 1, the molding temperature was changed to 270 ° C., and the mold temperature was changed to 80 ° C. Got the body. About this resin molding, mold release property, transparency, and protein adsorptivity were evaluated. The evaluation results are shown in Table 1.

[Example 5]
In Example 1, a resin molded body was obtained in the same manner as in Example 1 except that the pellet (C) was used instead of the pellet (A). About this resin molding, mold release property, transparency, and protein adsorptivity were evaluated. The evaluation results are shown in Table 1.

[Comparative Example 1]
In Example 1, a resin molded body was obtained in the same manner as in Example 1 except that a core subjected only to polishing treatment was used. About this resin molding, mold release property, transparency, and protein adsorptivity were evaluated. The evaluation results are shown in Table 1.

[Comparative Example 2]
A resin molded body was obtained in the same manner as in Example 1, except that the projection pressure was changed to 0.45 MPa and the surface roughness (Ra) of the core was changed to 0.22 μm. About this resin molding, mold release property, transparency, and protein adsorptivity were evaluated. The evaluation results are shown in Table 1.

[Comparative Example 3]
A resin molded body was obtained in the same manner as in Example 1, except that the projection pressure was changed to 0.65 MPa and the surface roughness (Ra) of the core was changed to 0.30 μm. About this resin molding, mold release property, transparency, and protein adsorptivity were evaluated. The evaluation results are shown in Table 1.

[Comparative Example 4]
In Example 1, a spherical alumina powder having an average particle diameter of 50 μm was used as the projection material, the projection pressure was changed to 0.1 MPa, and the surface roughness (Ra) of the core was changed to 0.50 μm. A resin molded body was obtained in the same manner as in Example 1. About this resin molding, mold release property, transparency, and protein adsorptivity were evaluated. The evaluation results are shown in Table 1.

[Comparative Example 5]
A resin molded body was obtained in the same manner as in Example 1 except that polycarbonate resin (PC) (manufactured by Bayer, product name “Macrolon Rx2435”) was used instead of pellet (A) in Example 1. About this resin molding, mold release property, transparency, and protein adsorptivity were evaluated. The evaluation results are shown in Table 1.

The following can be seen from Table 1.
The resin containers obtained in Examples 1 to 5 are excellent in transparency and are difficult to adsorb proteins or the like on the inner wall. Moreover, since it is excellent in releasability, it is hard to produce a scratch.
On the other hand, since the resin container obtained in Comparative Example 1 is inferior in releasability, scratches are likely to occur. Therefore, with this method, it is difficult to produce stably without causing appearance defects.
The resin containers obtained in Comparative Examples 2 to 4 are obtained using a core having a large surface roughness (Ra), are inferior in transparency, and easily adsorb proteins.
The resin container obtained in Comparative Example 5 uses a polycarbonate resin as a molding material and is very easy to adsorb proteins.

1. 1. Injection molding machine Injection unit 3. Mold 4. Cavity 5. Core 6. Space (Product Department)
7). Hopper 8. Cylinder 9. Screw 10. Nozzle 11. Plastic molded products (resin containers)
12 Drive device

Claims (5)

A method for producing a resin container, comprising a step of molding a molding material containing a cyclic olefin resin using a mold having a core and a cavity,
The method for producing a resin container, wherein the core has a surface roughness (Ra) of 0.02 to 0.20 μm.   The method for producing a resin container according to claim 1, wherein the core is obtained by roughening a core having a surface roughness (Ra) of less than 0.02 μm by a projection treatment method.   The manufacturing method of the resin-made containers of Claim 2 whose average particle diameter of the projection material used for a projection processing method is 10-30 micrometers.   The manufacturing method of the resin container in any one of Claims 1-3 whose resin container is an outer cylinder for prefilled syringes.   A resin container obtained by the production method according to claim 1.

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