JP2013132394A - Method for manufacturing outer cylinder for prefilled syringe, and method for manufacturing injection molding die - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide technologies for manufacturing an outer cylinder for a prefilled syringe with high transparency, manufactured with cyclic olefin resin as a raw material.SOLUTION: In the method for manufacturing the outer cylinder for the prefilled syringe molded by injecting a cyclic olefin resin composition, an injection molding die, wherein the surface roughness Rz (ten point average roughness) of a core constituting the injection molding die is 50 μm or lower, wherein a lubricative hard film containing at least one kind of element selected from Ti, Cr, Zr, C, Al and Ni is formed, and wherein the surface of the lubricative hard film is polished, is used as the injection molding die.

Description

  The present invention relates to a method for manufacturing a prefilled syringe outer cylinder and a method for manufacturing an injection mold that can be used in the manufacturing method.

  Conventional general syringes have been used by a method of sucking up a drug at the time of use. However, this method of use is prone to human error such as poor operation efficiency and drug filling errors. Therefore, recently, prefilled syringes filled with a predetermined amount of a predetermined drug in advance are preferably used.

  The material constituting the prefilled syringe is preferably a resin from the viewpoint of ease of handling such as light weight and resistance to cracking. However, a prefilled syringe manufactured using polypropylene used for manufacturing a general syringe has a problem of deformation due to steam sterilization before being filled with a drug because polypropylene has low heat resistance.

  In addition, depending on the type of resin used, as a result of insufficient chemical resistance of the resin, problems such as elution of components contained in the resin into the drug occur during storage of the prefilled syringe. Moreover, when the water vapor barrier property of the prefilled syringe is low, there arises a problem that water contained in the medicine volatilizes during storage.

  For this reason, the resin which can be used as a raw material of a prefilled syringe is limited, As an available resin, an aromatic vinyl type polymer as described in patent document 1 is mentioned, for example.

Japanese Patent Laid-Open No. 11-164877

  By the way, the cyclic olefin resin is known as a resin excellent in heat resistance, chemical resistance, water vapor barrier property and the like. Furthermore, since cyclic olefin resin is excellent also in transparency, when a prefilled syringe is manufactured using cyclic olefin resin, the effect that it will be easy to visually recognize a chemical | medical agent will also be acquired.

  For the purpose of improving the performance of a prefilled syringe made of resin, the present inventors tried to manufacture a prefilled syringe outer cylinder made of a cyclic olefin resin as a raw material, and the transparency of the manufactured prefilled syringe outer cylinder was It was not good and had a problem with moldability.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a technique for efficiently manufacturing a prefilled syringe outer cylinder that is manufactured using a cyclic olefin resin as a raw material and has high transparency. is there.

  In order to solve the above-mentioned problems, the present inventors have made extensive studies to produce a prefilled syringe outer cylinder that is manufactured using a cyclic olefin resin as a raw material and has high transparency. As a result, the surface roughness of the core (movable side) constituting the injection mold for molding the prefilled syringe outer cylinder is in a specific range, and a specific lubricating hard film is formed on the surface of the core. It was found that if the surface of the hard lubricating film formed was polished, a highly transparent prefilled syringe outer cylinder was obtained, and the present invention was completed. More specifically, the present invention provides the following.

  (1) A method for producing a prefilled syringe outer cylinder formed by injection molding of a cyclic olefin resin composition, wherein the surface roughness Rz (ten-point average roughness) of the core constituting the injection mold is 50 μm. An injection molding gold, wherein a lubricious hard film containing at least one element selected from Ti, Cr, Zr, C, Al and Ni is formed, and the surface of the lubricious hard film is further polished The manufacturing method of the outer cylinder for prefilled syringes which uses a type | mold and has a light transmittance of 70% or more when the light of wavelength 450nm incident perpendicularly | vertically with respect to the side wall of the outer cylinder for prefilled syringes permeate | transmits the said side wall.

  (2) The prefilled syringe outer cylinder according to claim 1, wherein the lubricious hard coating is composed of diamond-like carbon (DLC), CrN, TiN, TiC, TiCN, TiAlN, TiCrN, AlCrN, ZrN, or Ni. Manufacturing method.

  (3) The manufacturing method of the outer cylinder for prefilled syringes as described in (1) or (2) whose draft of the core which comprises an injection mold is substantially 0 degree | times.

  (4) An injection mold manufacturing method for manufacturing an injection mold for manufacturing a prefilled syringe outer cylinder, wherein the surface roughness Rz of the core constituting the injection mold is set to 50 μm or less. Core surface roughness adjusting step and lubricating hard film forming a lubricating hard film containing at least one element selected from Ti, Cr, Zr, C, Al and Ni on the core after the adjusting step An injection mold manufacturing method comprising: a film forming process; and a polishing process for polishing a surface of the lubricious hard film.

  According to the present invention, it is possible to efficiently produce a prefilled syringe outer cylinder having high transparency using a cyclic olefin resin as a raw material.

FIG. 1 is a diagram schematically showing a prefilled syringe, in which (a) is a perspective view and (b) is an MM cross-sectional view of (a). Fig.2 (a) is a figure which shows the dimension of the outer cylinder for prefilled syringes manufactured in the Example, (b) is a figure which shows the position of the sprue, runner, and gate in a metal mold | die. It is a schematic diagram for demonstrating the measuring method of light transmittance.

  Hereinafter, embodiments of the present invention will be described. In addition, this invention is not limited to the following embodiment.

  The present invention is a method for producing a prefilled syringe outer cylinder. The shape of the prefilled syringe outer cylinder manufactured in the present invention is not particularly limited. First, a general prefilled syringe in which the prefilled syringe outer cylinder of the present invention is used will be briefly described with reference to the drawings.

<Prefilled syringe>
FIG. 1 is a view schematically showing a prefilled syringe. The prefilled syringe 1 is inserted into the prefilled syringe outer cylinder 10 from the other end of the prefilled syringe outer cylinder 10, the cannula 20 connected to one end of the prefilled syringe outer cylinder 10, and the other end of the prefilled syringe outer cylinder 10. And a plunger 30.

  A luer 101 for connecting to the cannula 20 is formed at one end of the prefilled syringe outer cylinder 10, and a flange 102 is formed at the other end. Moreover, the space inside the outer cylinder 10 for prefilled syringes is a medicine storage space in which a medicine is stored. The plunger 30 is inserted from the opening of the prefilled syringe outer cylinder 10 on the flange 102 side. Moreover, as shown in FIG.1 (b), the draft of the inner wall surface of the prefilled syringe outer cylinder 10 was set to (theta).

  The cannula 20 has a stopper 201 at the end, and when the stopper 201 is fitted to the luer 101, the cannula 20 and the prefilled syringe outer cylinder 10 are connected.

  As described above, the plunger 30 is inserted through the end portion of the prefilled syringe outer cylinder 10 so as to be able to advance and retract. When the prefilled syringe is stored, the end of the plunger 30 is in contact with the medicine in the medicine housing space.

  Then, the manufacturing method of the outer cylinder for prefilled syringes is demonstrated easily. After storing the prefilled syringe 1 in a state filled with a medicine for a certain period of time, the plunger 30 is further pushed into the prefilled syringe outer cylinder 10 at the time of use, so that the volume of the medicine storage space is reduced and the lure is reduced. The drug is extruded from the portion 101, and the extruded drug passes through the cannula 20 and comes out of the prefilled syringe.

  As described above, the prefilled syringe 1 is stored for a certain period in a state where the medicine is accommodated therein. For this reason, when the outer cylinder 10 for prefilled syringes is comprised from the material with low water vapor permeability, the problem that the water | moisture content contained in a chemical | medical agent comes out outside arises.

  Further, if the medicine is stored in the prefilled syringe 1 for a long time, the state where the medicine and the inner wall surface of the prefilled syringe outer cylinder 10 are in contact with each other continues for a long time. Therefore, when the chemical resistance of the material constituting the prefilled syringe outer cylinder 10 is low, there arises a problem that a decomposition product of the material dissolves in the medicine.

  The prefilled syringe outer cylinder 10 obtained by the production method of the present invention is composed of a cyclic olefin resin composition described later. Since the cyclic olefin resin composition exhibits the excellent chemical resistance and water vapor barrier properties of the cyclic olefin resin, when the prefilled syringe outer cylinder is manufactured using the cyclic olefin resin composition, the above problems are Does not occur.

  However, when it is going to manufacture the outer cylinder for prefilled syringes using a cyclic olefin resin composition, the problem that the outer cylinder for prefilled syringes does not have sufficient transparency arises.

  Furthermore, when the prefilled syringe outer cylinder is manufactured using the cyclic olefin resin composition as a raw material, it is difficult to take out the prefilled syringe outer cylinder from the mold at the time of manufacture because of the inherent hardness of the cyclic olefin resin. The problem that it is difficult to take out the prefilled syringe outer cylinder from the mold at the time of manufacturing causes scratches on the inner surface of the outer cylinder, leading to a decrease in productivity as well as a decrease in transparency.

  In this invention, in order to manufacture the outer cylinder for prefilled syringes with the following method, the transparency of the outer cylinder for prefilled syringes manufactured using cyclic olefin resin can be improved.

  In particular, if manufactured under the preferable conditions of the present invention, the prefilled syringe outer cylinder can be easily taken out of the mold at the time of manufacturing, and the productivity of the high quality prefilled syringe outer cylinder can be increased.

<Method for producing prefilled syringe outer cylinder>
The manufacturing method of the outer cylinder for prefilled syringes of this invention is a manufacturing method of the outer cylinder for prefilled syringes formed by injection-molding a cyclic olefin resin composition.

  In the manufacturing method of the present invention, the surface roughness Rz of the core constituting the injection mold is 50 μm or less, and further includes at least one element selected from Ti, Cr, Zr, C, Al and Ni. A core that constitutes an injection mold in which a curable hard film is formed and the surface of the lubricious hard film is polished is used. The core constituting the injection mold may be manufactured in any way, but for example, the core constituting the injection mold manufactured by the following method can be used.

[Manufacturing method of core constituting injection mold]
As an example of the manufacturing method of the core which comprises the metal mold | die for injection molding, the manufacturing method which has the process of the following (i)-(iii) is mentioned.
(I) A core surface roughness adjusting step for setting the surface roughness Rz of the core constituting the injection mold to 50 μm or less.
(Ii) A lubricious hard film forming step of forming a lubricious hard film containing at least one element selected from Ti, Cr, Zr, C, Al and Ni on the core surface after the adjusting step.
(Iii) A polishing step for polishing the surface of the lubricious hard coating.

  The core surface roughness adjusting step (i) is, for example, a step of polishing the surface of the core using an abrasive having a particle size of 2,000 or higher in JIS R6010. Here, the surface roughness Rz decreases as the particle size count of the abrasive increases, and the surface roughness Rz increases as the particle size count decreases. For this reason, the surface roughness Rz can be adjusted by appropriately adjusting the particle size count of the abrasive. The specific method for polishing is not particularly limited. For example, a method using a polishing body such as diamond paper or a polishing body called liquid buffing material (compound) and cloth or sponge buff is used. Method, aero lapping, lathe or a combination of these methods.

  In the lubricating hard film forming step (ii), a lubricating hard film containing at least one element selected from Ti, Cr, Zr, C, Al and Ni is applied to the surface of the core after the step (i). Form. In the present invention, a lubricious hard coating composed of diamond-like carbon (DLC), CrN, TiN, TiC, TiCN, TiAlN, TiCrN, AlCrN, ZrN, or Ni is preferable.

  Examples of a method for forming a lubricious hard film on the surface of the core include a deposition method. As the deposition method, a vapor phase method is preferable. For example, a CVD method such as a plasma CVD (Chemical Vapor Deposition) method using a DC power source, an AC power source, or a high frequency power source as a power source, an AIP (Arc Ion Platting) method, or the like. Examples thereof include a PVD (Physical Vapor Deposition) method, a magnetron sputtering method, a sputtering method such as an ion beam sputtering method, and an ionization vapor deposition method. Moreover, in the case of Ni etc., wet methods, such as electrolytic plating and electroless plating, are mentioned. These lubricious hard coatings may be a single layer or multiple layers.

  The coating surface roughness adjusting step (iii) is a step of polishing the surface of the lubricious hard coating. And it is preferable that the surface roughness Rz of the lubricious hard film surface after grinding | polishing is 40 micrometers or less. The polishing method is not particularly limited, a method using a polishing body such as diamond paper, a method using a polishing body called liquid buffing material (compound) and cloth or sponge buff, an aero lapping, a lathe, or these A method combining these methods can be employed. In order to prevent the lubricious hard film from being removed during polishing, it is preferable to employ diamond paper.

[Core constituting injection mold]
As described above, in the present invention, a lubricious hard film containing at least one element selected from Ti, Cr, Zr, C, Al and Ni is formed on the surface having a surface roughness Rz of 50 μm or less. The surface of the conductive hard film is polished.

  In order to make a prefilled syringe outer cylinder that is highly transparent and can be easily taken out from the mold immediately after manufacturing, the surface roughness Rz is 50 μm or less for the purpose of reducing the surface roughness of the inner surface of the outer cylinder. It is necessary to form a hard film.

  Also, since the lubricious hard coating has a smaller coefficient of friction on the coating surface than the core surface, the lubricious hard coating is formed on the core surface, which makes it easier to take out the prefilled syringe outer cylinder from the mold immediately after manufacture. . However, if the surface of the lubricious hard coating is not polished, fine projections on the surface generated when the lubricious hard coating is formed will cause the prefilled syringe outer cylinder to be removed when the prefilled syringe outer cylinder is removed from the mold. The inner wall may be damaged. Therefore, in order to produce a highly transparent prefilled syringe outer cylinder, the surface of the lubricious hard coating must be polished even when the surface roughness Rz of the lubricious hard coating is small. .

  However, if the surface roughness Rz of the lubricious hard film after polishing is too large, the transparency of the prefilled syringe outer cylinder may be lowered. For this reason, the surface roughness of the lubricious hard film after polishing is preferably 40 μm or less.

<Cyclic olefin resin composition>
The cyclic olefin resin composition used as the raw material of the prefilled syringe outer cylinder will be described. The cyclic olefin resin composition contains a cyclic olefin resin.

  The cyclic olefin resin is not particularly limited as long as it contains a cyclic olefin component as a copolymerization component and is a polyolefin resin containing a cyclic olefin component in the main chain. For example, an addition polymer of a cyclic olefin or a hydrogenated product thereof, an addition copolymer of a cyclic olefin and an α-olefin, or a hydrogenated product thereof can be used.

  The cyclic olefin resin includes those obtained by grafting and / or copolymerizing an unsaturated compound having a polar group to the above polymer.

  Examples of the polar group include a carboxyl group, an acid anhydride group, an epoxy group, an amino group, an amide group, an ester group, a hydroxyl group, a sulfo group, a phosphono group, and a phosphino group. Saturated compounds include (meth) acrylic acid, maleic acid, maleic anhydride, itaconic anhydride, glycidyl (meth) acrylate, alkyl (meth) acrylate (carbon number 1 to 10) ester, alkyl maleate (carbon number 1 -10) ester, (meth) acrylamide, (meth) acrylic acid-2-hydroxyethyl and the like, preferably carboxyl group, acid anhydride group, epoxy group, amino group, amide group, ester group, A hydroxyl group, a sulfo group, a phosphono group, and a phosphino group are mentioned.

  As the cyclic olefin resin, an addition copolymer of a cyclic olefin and an α-olefin or a hydrogenated product thereof is preferable.

  A commercially available resin can also be used as the cyclic olefin resin containing a cyclic olefin component as a copolymerization component. Examples of commercially available cyclic olefin-based resins include TOPAS (registered trademark) (Topas Advanced Polymers), Apel (registered trademark) (manufactured by Mitsui Chemicals), Zeonex (registered trademark) (manufactured by Nippon Zeon), Examples include ZEONOR (registered trademark) (manufactured by ZEON Corporation), ARTON (registered trademark) (manufactured by JSR Corporation), and the like.

（式中、Ｒ^１〜Ｒ^１２は、それぞれ同一でも異なっていてもよく、水素原子、ハロゲン原子、及び、炭化水素基からなる群より選ばれるものであり、
Ｒ^９とＲ^１０、Ｒ^１１とＲ^１２は、一体化して２価の炭化水素基を形成してもよく、
Ｒ^９又はＲ^１０と、Ｒ^１１又はＲ^１２とは、互いに環を形成していてもよい。
また、ｎは、０又は正の整数を示し、
ｎが２以上の場合には、Ｒ^５〜Ｒ^８は、それぞれの繰り返し単位の中で、それぞれ同一でも異なっていてもよい。） Particularly preferred examples of the addition copolymer of cyclic olefin and α-olefin include: [1] an α-olefin component having 2 to 20 carbon atoms, and [2] a cyclic olefin component represented by the following general formula (I): Can be mentioned.

(Wherein R ^{1 to} R ¹² may be the same as or different from each other, and are selected from the group consisting of a hydrogen atom, a halogen atom, and a hydrocarbon group;
R ⁹ and R ¹⁰ , R ¹¹ and R ¹² may be integrated to form a divalent hydrocarbon group,
R ⁹ or R ¹⁰ and R ¹¹ or R ¹² may form a ring with each other.
N represents 0 or a positive integer;
When n is 2 or more, R ^{5 to} R ⁸ may be the same or different in each repeating unit. )

  [1] The α-olefin component having 2 to 20 carbon atoms will be described. The α-olefin having 2 to 20 carbon atoms is not particularly limited. For example, the thing similar to Unexamined-Japanese-Patent No. 2007-302722 can be mentioned. These α-olefin components may be used alone or in combination of two or more. Of these, ethylene is most preferably used alone.

[2] The cyclic olefin component represented by the general formula (I) will be described. R ^{1 to} R ¹² in the general formula (I) may be the same or different and are selected from the group consisting of a hydrogen atom, a halogen atom, and a hydrocarbon group.

Specific examples of R ^{1 to} R ⁸ include, for example, a hydrogen atom; a halogen atom such as fluorine, chlorine and bromine; a lower alkyl group such as a methyl group, an ethyl group, a propyl group and a butyl group. May be different from each other, may be partially different, or all may be the same.

Specific examples of R ^{9 to} R ¹² include, for example, hydrogen atom; halogen atom such as fluorine, chlorine, bromine; methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, hexyl group, stearyl. Alkyl group such as cyclohexyl group; cycloalkyl group such as cyclohexyl group; substituted or unsubstituted aromatic hydrocarbon group such as phenyl group, tolyl group, ethylphenyl group, isopropylphenyl group, naphthyl group, anthryl group; benzyl group, phenethyl And an aralkyl group in which an aryl group is substituted with an alkyl group, and the like. These may be different from each other, may be partially different, or all may be the same.

Specific examples of the case where R ⁹ and R ¹⁰ or R ¹¹ and R ¹² are integrated to form a divalent hydrocarbon group include, for example, alkylidene groups such as an ethylidene group, a propylidene group, and an isopropylidene group. Can be mentioned.

When R ⁹ or R ¹⁰ and R ¹¹ or R ¹² form a ring with each other, the formed ring may be monocyclic or polycyclic, or may be a polycyclic ring having a bridge. , A ring having a double bond, or a ring composed of a combination of these rings may be used. Moreover, these rings may have a substituent such as a methyl group.

  Specific examples of the cyclic olefin component represented by the general formula (I) include those similar to those described in JP-A-2007-302722.

  These cyclic olefin components may be used singly or in combination of two or more. Among these, it is preferable to use bicyclo [2.2.1] hept-2-ene (common name: norbornene) alone.

  [1] A method for polymerizing an α-olefin component having 2 to 20 carbon atoms and a [2] cyclic olefin component represented by formula (I) and a method for hydrogenating the obtained polymer are particularly limited. Instead, it can be carried out according to known methods. Random copolymerization or block copolymerization may be used, but random copolymerization is preferred.

  The polymerization catalyst used is not particularly limited, and a cyclic olefin resin can be obtained by a known method using a conventionally known catalyst such as a Ziegler-Natta, metathesis, or metallocene catalyst.

  Next, other copolymerization components will be briefly described. The cyclic olefin-based resin (A) does not impair the object of the present invention other than [1] the α-olefin component having 2 to 20 carbon atoms and [2] the cyclic olefin component represented by the general formula (I). In the range, other copolymerizable unsaturated monomer components may be contained as required.

  The unsaturated monomer that may be optionally copolymerized is not particularly limited, and examples thereof include hydrocarbon monomers containing two or more carbon-carbon double bonds in one molecule. Can be mentioned. Specific examples of the hydrocarbon-based monomer having two or more carbon-carbon double bonds in one molecule include those similar to those described in JP-A-2007-302722.

  When the cyclic olefin resin as described above is used, the prefilled syringe outer cylinder becomes hard. Therefore, even if the draft angle (θ in FIG. 1B) of the inner wall surface of the prefilled syringe outer cylinder is small, if the draft angle is not substantially zero, the plunger is pushed during use to prefill the prefilled syringe. This hinders the extruding of the medicine in the syringe outer cylinder. In addition, that the draft angle of the said inner wall surface is 0 degree | times means that the draft angle of the core which comprises an injection mold is substantially 0 degree | times.

  When manufacturing a prefilled syringe outer cylinder using resin, the draft angle of the inner wall surface of the prefilled syringe outer cylinder is substantially zero in order to make it easy to take out the prefilled syringe outer cylinder from the mold. Preferably not. However, if the above-described mold is used, the prefilled syringe outer cylinder immediately after manufacture can be easily taken out from the mold even when the draft is substantially zero.

  Here, the draft is substantially zero means that the draft is 0.5 degrees or less. And when the draft is 0.5 degrees or less, the problem of the above-mentioned difficulty arises.

  In addition, components other than cyclic olefin resin may be contained in cyclic olefin resin composition in the range which does not impair the effect of this invention. Examples of other components include other resins, inorganic fillers, nucleating agents, pigments, antioxidants, stabilizers, plasticizers, lubricants, mold release agents, and the like.

<Method for producing prefilled syringe outer cylinder>
The prefilled syringe outer cylinder of the present invention is manufactured by an injection molding method. The production conditions for injection molding are not particularly limited, and are appropriately set according to the cyclic olefin resin composition to be used.

<Outer cylinder for prefilled syringe>
The prefilled syringe manufactured by the manufacturing method of the present invention has high transparency. Specifically, the light transmittance when light having a wavelength of 450 nm incident perpendicularly to the side wall of the prefilled syringe outer cylinder passes through the side wall is 70% or more.

  Moreover, the larger the surface area of the prefilled syringe outer cylinder, the more difficult it is to take out the prefilled syringe outer cylinder immediately after manufacture from the mold. The length L of the prefilled syringe outer cylinder is usually 30 mm or more and 150 mm or less, and the inner diameter R of the prefilled syringe outer cylinder is usually 2 mm or more and 50 mm or less.

  Hereinafter, the present invention will be described more specifically based on examples, but the present invention is not limited to these examples.

[Injection mold]
In this example, a prefilled syringe outer cylinder having the shape shown in FIG. 1 is manufactured. The dimensions of the prefilled syringe outer cylinder are shown in FIG. Moreover, as shown to Fig.2 (a), the draft of an inner wall surface is 0 degree | times in the outer cylinder for prefilled syringes manufactured in the Example.

A mold having a cavity in the shape of the outer cylinder for a prefilled syringe includes a sprue, a runner, and a gate having a shape as shown in FIG. The gate position G is also shown in FIG. As shown in FIG. 2B, the sprue diameter, runner length, and gate diameter are 4.0 mm, 20 mm, and 3.0 mm, respectively. And as shown in FIG.2 (b), the three ejector pins are provided in the connection point of a sprue and a runner, and the connection point of a runner and a gate (PIN1-3). The ejector pin represented by PIN1 is connected to a pressure sensor (“9223A”, manufactured by Nippon Kistler) for measuring the mold release resistance. Data obtained from this pressure sensor is converted using an industrial charge amplifier (“5073A”, manufactured by Nippon Kistler), and the converted data can be monitored by DATA FLOW Light II (manufactured by Nippon Kistler). Yes.

  And the core of the metal mold | die with which the surface was processed on the conditions shown in Table 1 was prepared. The “grain size count” in Table 1 represents the grain size count of the abrasive used to treat the surface of the core. Examples 1 to 3 and Comparative Examples 1 to 5 are aero lapping processes performed using diamond abrasive grains, and Examples 4 and Comparative Examples 6 to 8 are polishing processes performed on a lathe using diamond paste. “Coating” in Table 1 represents the type of the lubricious hard film formed on the surface of the core subjected to the surface treatment. In this example, the lubricious hard coating was formed by electroless plating in the case of Ni, PVD in the case of CrN and TiN, and ionized vapor deposition in the case of DLC. Further, in Example 1, the surface of the lubricious hard film was polished with No. 2000 diamond paper, and in Examples 2 and 4, the surface of the lubricious hard film was polished with No. 4000 diamond paper. In No. 3, the surface of the lubricating hard film was polished with # 8000 diamond paper. The core steel used in this example was HPM-38 (quenched) manufactured by Hitachi Metals.

[Evaluation of surface roughness]
The surface roughness Rz of the core surface, the surface roughness Rz of the surface of the lubricious hard film, and the surface roughness Rz of the surface of the lubricated hard film after polishing were measured using the “Ultra-Deep Color 3D Shape Measurement Microscope” manufactured by Keyence Corporation. It measured by the method based on JISB0601-1994 using "VK-9500". The measurement results are shown in Table 1. The unit in Table 1 is μm.

[Manufacture of prefilled syringe outer cylinder]
As the cyclic olefin resin composition, a copolymer of norbornene and ethylene (TOPAS 6013S-04, manufactured by Topas Advanced Polymers, glass transition temperature of 138 ° C.) was used to produce outer cylinders for prefilled syringes of Examples and Comparative Examples. The manufacturing conditions are a mold temperature of 105 ° C. and a cylinder temperature of 280 ° C.

  When the outer cylinder for prefilled syringe immediately after production was taken out of the mold, the pressure applied to PIN1 was measured by the pressure sensor. The measurement results (maximum values in each measurement of Examples 1 to 4 and Comparative Examples 1 to 8) are shown in Table 1 as release resistance values. In addition, continuous moldability was set to "(circle)" when the mold release resistance value was less than 10.0 MPa, and continuous moldability was set to "x" when 10.0 MPa or more.

[Evaluation of transparency]
For the transparency of the prefilled syringe outer cylinders of Examples 1 to 4 and Comparative Examples 1 to 8, “Integrating sphere device ISN-470 type” was set in “UV-visible spectrophotometer V-570” manufactured by JASCO Corporation. Measurement was performed using an apparatus. The sample was cut in half in the direction in which the prefilled syringe outer cylinder extends, and a cylindrical sample divided into two was cut out from here (here, 17.1 from the connecting position of the luer part and the prefilled syringe outer cylinder. The area around 5 mm was cut out). The cut sample was set in a sample fixing holder as shown in FIG. 3, and the light transmittance with respect to 450 nm light was measured. The measurement results are shown in Table 1. The unit in Table 1 is%.

[Evaluation of the presence or absence of scratches]
The scratches on the surfaces of the prefilled syringe outer cylinders of Examples 1 to 4 and Comparative Examples 1 to 8 were visually confirmed. The following two-stage evaluation was performed for the presence or absence of scratches. The evaluation results are shown in Table 1.
“○”: When there are 3 or less scratches “×”: When there are 4 or more scratches

  From the results of Table 1, in the method for producing a prefilled syringe outer cylinder formed by injection molding of a cyclic olefin resin composition, as a mold for injection molding, a core having a surface roughness Rz of 50 μm or less, Ti, Cr, By using an injection mold in which a lubricious hard film containing at least one element selected from Zr, C, Al and Ni is formed and the surface of the lubricious hard film is polished, there is no damage. It was confirmed that the prefilled syringe outer cylinder excellent in transparency can be produced with high productivity.

DESCRIPTION OF SYMBOLS 1 Prefilled syringe 10 Outer cylinder for prefilled syringe 101 Luer 102 Flange 20 Cannula 201 Stopper 30 Plunger

Claims (4)

A method for producing a prefilled syringe outer cylinder formed by injection molding a cyclic olefin resin composition,
Lubricant containing at least one element selected from Ti, Cr, Zr, C, Al and Ni, having a surface roughness Rz (ten-point average roughness) of a core constituting the injection mold of 50 μm or less An injection mold in which the surface of the lubricious hard film is further polished,
The manufacturing method of the outer cylinder for prefilled syringes whose light transmittance is 70% or more when the light with a wavelength of 450 nm incident perpendicularly to the side wall of the outer cylinder for prefilled syringes is transmitted through the side wall.   The method for producing an outer cylinder for a prefilled syringe according to claim 1, wherein the lubricious hard coating is composed of diamond-like carbon (DLC), CrN, TiN, TiC, TiCN, TiAlN, TiCrN, AlCrN, ZrN, or Ni. .   The manufacturing method of the outer cylinder for prefilled syringes according to claim 1 or 2, wherein the draft angle of the core constituting the injection mold is substantially 0 degrees. An injection mold manufacturing method for manufacturing an injection mold for manufacturing a prefilled syringe outer cylinder,
A core surface roughness adjusting step of setting the surface roughness Rz of the core constituting the injection mold to 50 μm or less;
Lubricating hard film forming step of forming a lubricating hard film containing at least one element selected from Ti, Cr, Zr, C, Al and Ni on the core surface after the adjusting step;
And a polishing step of polishing the surface of the lubricious hard coating.

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