JP2019156913A - Polyethylene resin composition and container - Google Patents

Abstract

To provide a resin composition excellent in transparency and heat resistance, and good in blow moldability, especially drawdown resistance.SOLUTION: There is provided a polyethylene resin composition containing high density polyethylene (A) of 20 to 30 pts.wt., linear low density polyethylene (B) of 20 to 40 pts.wt., an ethylene polymer (C) satisfying following properties of (e) to (h) of 25 to 35 pts.wt., and high pressure low density polyethylene (D) of 5 to 25 pts.wt., (total of (A), (B), (C) and (D) is 100 pts.wt.). (e) density is 930 to 949 kg/m. (f) MFR is 0.1 to 10 g/10 min. (g) 2 peaks are shown in molecular weight measurement by GPC and Mw/Mn is in a range of 2.0 to 7.0. (h) there is 0.15 or more long chain branches of a hexyl group or more in a fraction with Mn of 100,000 or more at molecular weight separation per 1000 main chains.SELECTED DRAWING: None

Description

  The present invention relates to a polyethylene resin composition and a container. More specifically, the present invention relates to a resin composition containing a specific high-density polyethylene, a linear low-density polyethylene, an ethylene polymer and a high-pressure process low-density polyethylene, and a container comprising the same.

  Containers filled with foods, medical solutions, and the like are produced by melt-molding thermoplastic resins such as polyethylene and polypropylene. In general, products filled with the contents in these containers are heat sterilized. In particular, infusion preparations or the like directly administered to blood are strictly required to be kept in a sterile state, and in recent years, high-temperature sterilization at 121 ° C. is becoming a global standard. In addition, containers for medical chemicals are required to be transparent enough to ensure the visibility of the chemicals, and are required to exceed the level of transparency prescribed by the Japanese Pharmacopoeia. Polypropylene is widely used as a raw material for containers that satisfy the above-mentioned transparency and heat resistance. However, it is essential to add an antioxidant because polypropylene has tertiary carbon repeatedly and is inherently susceptible to oxidative degradation. It has become. In recent years, the demand for safety has increased, and therefore, a clean material with no additive has been favored particularly in containers for medical chemicals. Therefore, the appearance of a new medical container having both transparency and heat resistance using an additive-free material in place of polypropylene is desired.

  In general, polyethylene is well known to be inherently less susceptible to oxidative degradation than polypropylene, and additive-free polyethylene resins are suitable for medical drug containers that do not require high heat resistance. Has been. It is also generally known that polyethylene has a higher crystallinity, that is, a higher density polyethylene has higher heat resistance. High-density polyethylene has a melting point of about 130 ° C. and high heat resistance, but it is known that it becomes opaque because a higher order structure called spherulite that scatters light develops greatly. Proportional to the square of the crystal volume). On the other hand, low density polyethylene has a small spherulite size and thus has good transparency, but has a melting point of about 110 ° C., and therefore cannot cope with high temperature heat sterilization.

  Here, since polyethylene is known to have fine spherulites when quenched from a molten state, a molding method having a rapid cooling process such as water-cooled inflation molding has been established as a method for improving transparency. Yes. However, since the spherulite growth rate of polyethylene is very fast, it is difficult to make a high-density polyethylene container transparent by optimizing the cooling conditions. For the same reason, it is also difficult to improve the transparency of polyethylene by a molding method with slow cooling such as blow molding. That is, existing polyethylene cannot be used as a raw material for containers that require high-temperature heat sterilization because transparency and heat resistance are contradictory.

  Under these circumstances, in order to produce polyethylene containers that have both transparency and heat resistance, various proposals such as polyethylene-based resin compositions and multilayer containers, as well as polyethylene resins with specific physical properties, etc. (For example, refer to Patent Documents 1, 2, 3, and 4). Furthermore, the present inventors can provide a medical container excellent in transparency, heat resistance, and cleanness by using a polyethylene resin composition containing a specific amount of a polyethylene resin having specific physical properties. (See, for example, Patent Document 5).

JP 2002-265705 A Japanese Patent Laid-Open No. 2005-7888 JP 2015-42557 A JP 2008-18063 A JP-A-2015-74744

  However, in the methods proposed in Patent Documents 1, 2, and 3, further improvements have been required to improve the balance between transparency and heat resistance. Further, in the method proposed in Patent Document 4, the cost of manufacturing is reduced because the material cost is higher than the case of using only polyethylene that can be manufactured at low cost in order to laminate the cyclic polyolefin that is expensive to manufacture. Is required. Furthermore, in the method proposed in the above-mentioned Patent Document 5, due to further research by the present inventors, the parison (cylindrical molten resin that hangs down from the die lip) easily hangs down during blow molding. It has become clear that there are molding problems such as poor parison cutting and failure to maintain container shape. The phenomenon that the parison hangs down due to its own weight is referred to as drawdown, and the property imparted to the resin so that the parison does not easily hang down is referred to as drawdown resistance.

  As a result of intensive studies to solve the above problems, the present inventors have found that a specific high-density polyethylene, a linear low-density polyethylene, an ethylene polymer, and a high-pressure method low-density polyethylene resin composition have transparency. It has been found that a container obtained by blow molding the resin composition can be suitably used for a pharmaceutical container requiring high-temperature sterilization because of excellent heat resistance and blow moldability, particularly, drawdown resistance. The present invention has been completed.

That is, the present invention provides a high-density polyethylene (A) that satisfies the following characteristics (a) to (b): 20 to 30% by weight and a linear low-density polyethylene (B) that satisfies the following characteristics (c) to (d): ) 20-40% by weight, ethylene polymer (C) satisfying the following characteristics (e)-(h) 25-35% by weight, high-pressure process low density polyethylene satisfying the following characteristics (i)-(j) ( D) 5 to 25% by weight (the total of (A), (B), (C), and (D) is 100% by weight), and relates to a polyethylene resin composition and a container.
(A) The density is from 950 to 970 kg / m ³ .
(B) Memelt mass flow rate (hereinafter referred to as MFR) measured at a temperature of 190 ° C. and a load of 21.18 N in accordance with JIS K6924-1 is 0.1 to 10 g / 10 minutes.
(C) The density is 890 to 915 kg / m ³ .
(D) MFR is 0.1-10 g / 10min.
(E) The density is 930-949 kg / m ³ .
(F) MFR is 0.1-10 g / 10min.
(G) Two peaks are shown in the molecular weight measurement by gel permeation chromatography, and the ratio (Mw / Mn) of the weight average molecular weight (Mw) to the number average molecular weight (Mn) is in the range of 2.0 to 7.0. It is.
(H) The fraction having a Mn of 100,000 or more when molecular weight fractionation has 0.15 or more long-chain branches having a hexyl group or more per 1000 carbons of the main chain.
(I) The density is from 918 to 925 kg / m ³ .
(J) MFR is 0.1 to 2.0 g / 10 min.

The high-density polyethylene (A) is an ethylene homopolymer or a copolymer of ethylene and α-olefin, and has a density measured according to JIS K6922-1 of 950 to 970 kg / m ³ , preferably 951 to 965 kg / m ³ . Moreover, MFR measured by 190 degreeC and the load 21.18N is 0.1g / 10min-10g / 10min, Preferably it is 1.0min -5.0g / 10min. When the density is less than 950 kg / m ³ , the heat resistance is deteriorated. On the other hand, when the density exceeds 970 kg / m ³ , the transparency is lowered. When the MFR is less than 0.1 g / 10 min, the fluidity during processing is deteriorated, so that the surface of the molded body is rough and transparency is impaired. On the other hand, if it exceeds 10 g / 10 minutes, the draw-down resistance during processing decreases, and the production of the container becomes impossible.

High-density polyethylene (A) improves the transparency of the resulting molded product by blending with linear low-density polyethylene (B), ethylene polymer (C), and high-pressure low-density polyethylene (D) described later. Although the effect is exhibited, when the high-density polyethylene (A) has the following characteristics (k) to (l), the cleanness (low particle size) of the molded body and the transparency after sterilization treatment are further improved. Particularly preferred. High density polyethylene (A) having such properties (k) to (l) can be produced by using the metallocene catalyst.
(K) The ratio (Mw / Mn) of the weight average molecular weight (Mw) to the number average molecular weight (Mn) determined by gel permeation chromatography is 3.0 or less.
(L) Residue by the ignition residue test method prescribed in the Japanese Pharmacopoeia is 0.02% by weight or less.

  The high-density polyethylene (A) may be a commercially available product. For example, Nisoron Hard 5700 manufactured by Tosoh Corporation (trade name), Nipolon Hard 8500 manufactured by Tosoh Corporation (trade name), Tosoh Corporation Product (trade name) Nipolon Hard 8022 and the like. Moreover, a high density polyethylene (A) can be manufactured with the following method. For example, it can be produced by a production method such as a slurry method, a solution method, or a gas phase method. When producing the high-density polyethylene (A), a Ziegler catalyst generally comprising a solid catalyst component containing magnesium and titanium and an organoaluminum compound, an organic transition metal compound containing a cyclopentadienyl derivative, and It is possible to use a metallocene catalyst, a vanadium-based catalyst, or the like composed of a compound and / or an organometallic compound that reacts with an ionic complex to homopolymerize ethylene or copolymerize ethylene and α-olefin. Can be manufactured. The α-olefin may be generally referred to as α-olefin, and α-olefin having 3 to 12 carbon atoms such as propylene, butene-1, hexene-1, octene-1, and 4-methyl-1-pentene. Preferably it is an olefin. Examples of the copolymer of ethylene and α-olefin include an ethylene / hexene-1 copolymer, an ethylene / butene-1 copolymer, and an ethylene / octene-1 copolymer.

The linear low density polyethylene (B) is a copolymer of ethylene and α-olefin, and has a density measured according to JIS K6922-1 of 890 to 915 kg / m ³ , preferably 895 to 910 kg / m. ³ . Moreover, MFR measured by 190 degreeC and the load 21.18N is 0.1g / 10min-10g / 10min, Preferably it is 1.0min -5.0g / 10min. When the density is less than 890 kg / m ³ , the heat resistance is deteriorated. On the other hand, when the density exceeds 915 kg / m ³ , the transparency after the heat treatment is significantly lowered. When the MFR is less than 0.1 g / 10 min, the fluidity during processing is deteriorated, so that the surface of the molded body is rough and transparency is impaired. On the other hand, if it exceeds 10 g / 10 minutes, the draw-down resistance during processing decreases, and the production of the container becomes impossible.

The linear low-density polyethylene (B) is a transparent molded article obtained by blending with the above-mentioned high-density polyethylene (A), the ethylene polymer (C) described later, and the high-pressure method low-density polyethylene (D). When the linear low-density polyethylene (B) has the following properties (m) to (n), the molded product is clean (low particle size) and is transparent after sterilization. Is particularly preferable since it is further improved. Such a linear low density polyethylene (B) having the characteristics (m) to (n) can be produced by using the metallocene catalyst.
(M) The ratio (Mw / Mn) of the weight average molecular weight (Mw) to the number average molecular weight (Mn) determined by gel permeation chromatography is 3.0 or less.
(N) The amount of n-heptane extracted at 50 ° C. is 1.5 wt% or less.

  As linear low density polyethylene (B), what was obtained as a commercial item may be used, for example, Tosoh Co., Ltd. (brand name) Nipolon-ZHF212R, Tosoh Corporation (brand name) Nipolon -Z HF210K, Tosoh Corporation (trade name) Nipolon-Z ZF220, and the like.

  Moreover, a linear low density polyethylene (B) can be manufactured with the following method. For example, it can be produced by a production method such as a high pressure method, a solution method, or a gas phase method. When the linear low density polyethylene (B) is produced, a solid catalyst component generally containing magnesium and titanium, a Ziegler catalyst comprising an organoaluminum compound, and an organic transition metal compound containing a cyclopentadienyl derivative And a metallocene catalyst, a vanadium-based catalyst, or the like comprising a compound and / or an organometallic compound that reacts with this to form an ionic complex, and by copolymerizing ethylene and an α-olefin by the catalyst. It can be manufactured. The α-olefin may be generally referred to as α-olefin, and α-olefin having 3 to 12 carbon atoms such as propylene, butene-1, hexene-1, octene-1, and 4-methyl-1-pentene. Preferably it is an olefin. Examples of the copolymer of ethylene and α-olefin include an ethylene / hexene-1 copolymer, an ethylene / butene-1 copolymer, and an ethylene / octene-1 copolymer.

The ethylene polymer (C) has a density according to JIS K6922-1 in the range of 930 to 949 kg / m ³ , preferably in the range of 935 to 945 kg / m ³ . Moreover, MFR measured by 190 degreeC and the load 21.18N is 0.1g / 10min-10g / 10min, Preferably it is 1.0min -5.0g / 10min. In addition, two peaks are shown in the molecular weight measurement by gel permeation chromatography (hereinafter referred to as GPC), and the ratio (Mw / Mn) of the weight average molecular weight (Mw) to the number average molecular weight (Mn) is 2.0. It is in the range of -7.0. The peak top molecular weight (Mp) is obtained by dividing the molecular weight distribution curve obtained by GPC measurement into two peaks by the method described later, and evaluating the top molecular weight of the high molecular weight side peak and the low molecular weight side peak. The case where the difference is 100,000 or more is defined as having two Mp. When it was less than 100,000, the top molecular weight of the actually measured molecular weight distribution curve was defined as one Mp. The molecular weight distribution curve was divided as follows. The standard deviation is 0.30 with respect to LogM of the molecular weight distribution curve in which the weight ratio is plotted against LogM which is the logarithm of molecular weight obtained by GPC measurement, and an arbitrary average value (molecular weight at the peak top position) A composite curve is created by adding together two logarithmic distribution curves having) at an arbitrary ratio. Further, the average value and the ratio are obtained so that the deviation sum of squares of the weight ratio with respect to the same molecular weight (M) value of the actually measured molecular weight distribution curve and the composite curve becomes a minimum value. The minimum value of the deviation sum of squares was set to 0.5% or less with respect to the deviation sum of squares when the ratios of the respective peaks were all zero. When the average value and the ratio giving the minimum value of the deviation sum of squares were obtained, the molecular weight at the peak top of each logarithmic distribution curve obtained by dividing into two lognormal distribution curves was defined as Mp. Furthermore, the number of long chain branches of the fraction having Mn of 100,000 or more obtained by molecular weight fractionation is 0.15 or more per 1000 carbons of the main chain. When the density is less than 930 kg / m ³ , the heat resistance is deteriorated. On the other hand, if the density exceeds 949 kg / m ³ , the transparency will be significantly reduced. When the MFR is less than 0.1 g / 10 min, the fluidity during processing is deteriorated, so that the surface of the molded body is rough and transparency is impaired. On the other hand, if it exceeds 10 g / 10 minutes, the draw-down resistance during processing decreases, and the production of the container becomes impossible. Ethylene polymer having one peak in molecular weight measurement by GPC, ethylene / α-olefin copolymer is an ethylene polymer having two peaks even if it is used as one component for obtaining the polyethylene resin composition of the present invention. As in the case of blending the polymer (C), a medical container having high transparency and maintaining transparency even after sterilization cannot be obtained. When Mw / Mn is less than 2.0, the fluidity at the time of processing is deteriorated, so that the surface of the molded body is rough and transparency is impaired. On the other hand, when Mw / Mn exceeds 7.0, an increase in low molecular weight components causes a decrease in mechanical strength and an increase in fine particles of the molded product. When the number of long-chain branches in the fraction with Mn of 100,000 or more is less than 0.15 per 1000 carbons of the main chain, even if it is used as one component for obtaining the polyethylene resin composition of the present invention, it is remarkably transparent The effect of improving the properties cannot be obtained.

  The ethylene polymer (C) is produced using a metallocene catalyst. The metallocene catalyst to be used has one metallocene complex, an activation cocatalyst, and, if necessary, an organoaluminum compound as constituents. At the same time as the synthesis of the macromonomer, the macromonomer, ethylene, and an olefin having 3 to 6 carbon atoms. It is preferable to carry out copolymerization.

  The macromonomer is an olefin polymer having a vinyl group at the terminal, and is an ethylene copolymer having a vinyl group at the terminal obtained by copolymerizing ethylene and an olefin having 3 to 6 carbon atoms. Non-bridged bis (indenyl) zirconium complexes and non-bridged bis (cyclopentadienyl) as metallocene complexes of metallocene catalysts that synthesize macromonomers and copolymerize macromonomers, ethylene and olefins having 3 to 6 carbon atoms Zirconium complex, bridged bis (cyclopentadienyl) zirconium complex, bridged bis (indenyl) zirconium complex, bridged (cyclopentadienyl) (indenyl) zirconium complex, bridged (cyclopentadienyl) (fluorenyl) zirconium A catalyst using a complex or a bridged (indenyl) (fluorenyl) zirconium complex is preferred. Specific examples of metallocene complexes include, for example, bis (indenyl) zirconium dichloride, dimethylsilanediylbis (cyclopentadienyl) zirconium dichloride, dimethylsilanediyl (cyclopentadienyl) (indenyl) zirconium dichloride, dimethylsilanediyl (cyclopenta). Dienyl) (2-methylindenyl) zirconium dichloride, dimethylsilanediyl (cyclopentadienyl) (4,7-dimethylindenyl) zirconium dichloride, dimethylsilanediyl (cyclopentadienyl) (2,4,7- Trimethylindenyl) zirconium dichloride, diphenylmethylene (1-cyclopentadienyl) (9-fluorenyl) zirconium dichloride, diphenylmethylene (1-cyclopenta Dichlorides such as enyl) (2,7-di-t-butyl-9-fluorenyl) zirconium dichloride, isopropylidene (1-cyclopentadienyl) (2,7-di-t-butyl-9-fluorenyl) zirconium dichloride Examples of the transition metal compound include dimethyl, diethyl, dihydro, diphenyl, and dibenzyl. Moreover, although the compound which substituted the zirconium atom of the said transition metal compound with the titanium atom or the hafnium atom can also be illustrated, it is not limited to these. Among these, one kind or plural kinds may be used, but one kind is particularly preferred.

  The activation co-catalyst used as a component of the metallocene catalyst is a metallocene complex or a compound that plays a role in converting a reaction product of a metallocene complex and an organoaluminum compound into an active species capable of olefin polymerization. It is preferable that it is a compound which produces | generates a reactive compound, and the produced | generated cationic compound acts as a polymerization active seed | species which can superpose | polymerize an olefin. An activation co-catalyst is a compound that provides a compound that, after forming a polymerization active species, coordinates weakly or interacts with the generated cationic compound, but does not react directly with the active species.

  Specific examples of the activation promoter include alkylaluminoxanes such as methylaluminoxane, silica gel-supported alkylaluminoxanes, tris (fluorinated aryl) borons such as tris (pentafluoreophenyl) boron, N, N-dimethylammonium-tetrakis ( Examples thereof include boron compounds such as tetrakis (fluorinated aryl) boron salts such as pentafluorophenyl) boron, silica gel-supported materials thereof, clay minerals, clay minerals treated with organic compounds, and the like. Among them, it is preferable to use a clay mineral treated with an organic compound.

  When a clay mineral treated with an organic compound is used as the activation promoter, the clay mineral used is preferably a clay mineral belonging to the smectite group, and specific examples include montmorillonite, beidellite, saponite, hectorite and the like. It is also possible to use a mixture of a plurality of these clay minerals.

  The organic compound treatment means introducing an organic ion between clay mineral layers to form an ionic complex. Examples of the organic compound used in the organic compound treatment include N, N-dimethyl-n-octadecylamine hydrochloride, N, N-dimethyl-n-eicosylamine hydrochloride, N, N-dimethyl-n-docosylamine hydrochloride, N, N-dimethyloleylamine hydrochloride, N, N-dimethylbehenylamine hydrochloride, N-methyl-bis (n-octadecyl) amine hydrochloride, N-methyl-bis (n-eicosyl) amine hydrochloride, N-methyl -Alkylammonium salts such as dioleylamine hydrochloride, N-methyl-dibehenylamine hydrochloride, N, N-dimethylaniline hydrochloride can be exemplified.

The metallocene catalyst is not particularly limited in the method for preparing the metallocene catalyst such as a method in which a metallocene complex is reacted with an activation promoter.
As the metallocene catalyst, an alkylaluminum such as triethylaluminum or triisobutylaluminum may be used as necessary for the activation of the metallocene complex and the removal of impurities in the solvent during the preparation of the catalyst.

  When the ethylene polymer (C) is produced, it is preferably carried out at a polymerization temperature of −100 to 120 ° C., preferably 20 to 120 ° C. in view of productivity, and more preferably in the range of 60 to 120 ° C. It is preferable. The polymerization time is preferably in the range of 10 seconds to 20 hours, and the polymerization pressure is preferably in the range of normal pressure to 300 MPa. The polymerizable monomer is ethylene and an α-olefin having 3 to 6 carbon atoms, and the supply ratio of ethylene and the α-olefin having 3 to 6 carbon atoms is ethylene / α-olefin having 3 to 6 carbon atoms ( A feed ratio of 1 to 200, preferably 3 to 100, and more preferably 5 to 50 can be used. It is also possible to adjust the molecular weight using hydrogen during polymerization. The polymerization can be carried out by any of batch, semi-continuous and continuous methods, and can be carried out in two or more stages by changing the polymerization conditions. The ethylene / α-olefin copolymer can be separated and recovered from the polymerization solvent by a conventionally known method after completion of the polymerization, and dried to obtain.

  The polymerization can be carried out in a slurry state, a solution state or a gas phase state. In particular, when the polymerization is carried out in a slurry state, polyethylene having a powder particle shape can be produced efficiently and stably. The ethylene polymer (C) can be produced by a known method such as JP-A-2011-105934. Moreover, Tosoh Co., Ltd. (brand name) TOSOH-HMS CK37, CK47 etc. can be used as a commercial item.

The high-pressure method low density polyethylene (D) has a density according to JIS K6922-1 of 918 to 925 kg / m ³ , preferably 919 to 924 kg / m ³ , and MFR measured at 190 ° C. and a load of 21.18 N. However, it is 0.1 g / 10 min or more and less than 2.0 g / 10 min, preferably 0.2 min or more and less than 1.0 g / 10 min. When the density is less than 918 kg / m ³ , the heat resistance is deteriorated. On the other hand, when the density exceeds 925 kg / m ³ , the transparency after the heat treatment is significantly lowered. When the MFR is less than 0.1 g / 10 min, the fluidity during processing is deteriorated, so that the surface of the molded body is rough and transparency is impaired. Moreover, when it exceeds 2 g / 10 minutes, the drawdown resistance at the time of processing will fall, and manufacture of a container will become impossible.

  The high-pressure low-density polyethylene (D) may be a commercially available product. For example, Tosoh Corporation (trade name) Petrocene 170K, Tosoh Corporation (trade name) Petrocene 175K, Tosoh Corporation (Product name) Petrocene 172, etc. can be mentioned. Here, the high-pressure method indicates radical polymerization of ethylene at high temperature and high pressure. From the high-pressure radical polymerization of ethylene, low-density polyethylene having a dendritic structure (a structure having both long-chain branches and short-chain branches) is polymerized. It is generally known that the structure is different from a low-density polyethylene (structure having only short-chain branches) (linear low-density polyethylene).

  The blending ratio of the high density polyethylene (A), the linear low density polyethylene (B) and the ethylene polymer (C), and the high pressure method low density polyethylene (D) constituting the polyethylene resin composition of the present invention is high density. 20-30 parts by weight of polyethylene (A), 20-40 parts by weight of linear low density polyethylene (B), 25-35 parts by weight of ethylene polymer (C), low pressure polyethylene (D) 5 to 25 parts (total of (A), (B), (C) and (D) is 100 parts by weight). When the high density polyethylene (A) is less than 20 parts by weight, the heat resistance is insufficient, and when it exceeds 30 parts by weight, the transparency is lowered, which is not preferable. When the linear low density polyethylene (B) is less than 20 parts by weight, the transparency is insufficient, and when it exceeds 40 parts by weight, the heat resistance is lowered, which is not preferable. When the ethylene polymer (C) is less than 25 parts by weight, the transparency is lowered, and when it exceeds 35% by weight, the heat resistance is insufficient, which is not preferable. If the high-pressure low-density polyethylene (D) is less than 5 parts by weight, the drawdown resistance is insufficient, and if it exceeds 25 parts by weight, the transparency is lowered, which is not preferable.

  The polyethylene resin composition of the present invention is prepared by using the above-described high-density polyethylene (A), linear low-density polyethylene (B), ethylene-based polymer (C), and high-pressure method low-density polyethylene (D). For example, a method of mixing with a Henschel mixer, V-blender, ribbon blender, tumbler blender, or the like, or a mixture obtained by such a method is further melt-kneaded with a single screw extruder, twin screw extruder, kneader, Banbury mixer, etc. Later, it can be obtained by granulation.

  In the polyethylene resin composition of the present invention, known additives generally used, for example, an antioxidant, a neutralizing agent, an antistatic agent, a lubricant, an antiblocking agent, an antifogging, are used as long as the effects of the present invention are not significantly impaired. An agent, an organic or inorganic pigment, an ultraviolet absorber, a dispersant and the like can be appropriately blended as necessary. The method of blending the above-mentioned additives into the resin composition used in the present invention is not particularly limited. For example, a method of directly adding in the pellet granulation step after polymerization, or a high-concentration master batch in advance. The method of producing and dry blending this at the time of shaping | molding etc. is mentioned.

  In addition, the polyethylene resin composition of the present invention is blended with other thermoplastic resins such as ethylene-propylene copolymer rubber and poly-1-butene within a range that does not impair the effects of the present invention. It can also be used.

  The container molding method of the present invention includes water-cooled or air-cooled inflation molding, cast (T-die) molding, blow molding, sheet molding, rotational molding, injection (biaxial stretching) blow molding, injection molding, tube molding, and dry molding. A molding method such as lamination molding or extrusion lamination molding is used, and these are used in a single layer or multiple layers. Although there is no particular limitation, blow molding is preferred from the viewpoints of hygiene and economy.

  The container of the present invention can also be manufactured using a blow-fill-seal machine having an extruder and a blow molding die. Specifically, a cylindrical molten parison is molded using an extruder provided with a blow molding die. Next, this cylindrical parison is sandwiched between split molds for molding the container body, and air is pressed into the interior, and at the same time, the container body is molded by sucking the parison through the vacuum holes installed in the mold surface. Then, the container main body is filled with a predetermined and predetermined amount of chemical solution. Furthermore, the container of the present invention is formed by sandwiching the mouth part of the container with a split mold and molding a fusion part that seals the mouth part and a twisted part that is connected to the fusion part. Can be manufactured.

  The container of the present invention is a medical container provided with a storage part that stores a chemical solution. For example, the storage part has a high-density polyethylene (A), a linear low-density polyethylene (B), or an ethylene polymer (C). And a resin composition containing high-pressure low-density polyethylene (D). The thickness of the container is practically 0.2 to 1.0 mm, preferably 0.3 to 0.9 mm. In addition, when a container is formed by blow molding, a thin-walled portion and a thick-walled portion are formed due to the properties of molding, and 0.1 to 0 at the corner of the container bottom relative to the average thickness of the container body portion. An uneven thickness of about 5 mm may occur.

  The container of the present invention is not particularly limited when sterilization of the product is required, but a high pressure steam sterilization method can be used. This high-pressure steam sterilization method is a method of heating and sterilizing for a certain period of time using saturated water vapor that has been pressurized to increase the temperature. This method is performed at 105 ° C. for 45 minutes at 115 ° C. in the Japanese Pharmacopoeia. The conditions for 30 minutes at 121 ° C or 15 minutes at 121 ° C are determined, and the processing conditions are determined by the material quality of the product and the safety of the product after sterilization. For sterilization of containers containing drugs such as blood bags and infusions, This is a commonly used method. Although not particularly limited, 121 ° C. is preferable as the sterilization temperature of the transparent container of the present invention from the viewpoint of safety. As for the transparency of the container after sterilization, if the light transmittance at 450 nm when measured using water as a control is 55% or more, the contents of the container can be sufficiently confirmed, and the Japanese Pharmacopoeia standard is achieved. it can. Moreover, what does not deform | transform after a sterilization process at 121 degreeC is preferable. Here, the deformation is the difference between the visual observation results of the container shape after sterilization and the container shape before sterilization. If there is no deformation, the container shape is kept almost the same as before sterilization. It can be used as a product filled with

  Applications of the transparent container of the present invention include medical containers, food containers, cosmetic containers and the like. Examples of the medical container include an infusion preparation container, an ampoule preparation container, a kit preparation container, and an eye drop container. Examples of food containers include various beverage containers, concentrated beverage containers, seasoning containers, sugar beet containers, dressing containers, mayonnaise and ketchup containers, various retort food containers, and baby bottles. Examples of cosmetic containers include containers such as hair conditioners, hair preparations, perfumes, hair dyes, eye shadows, nail varnishes, lotions, creams, emulsions, lotions, and permanent liquids.

  Since the resin composition of the present invention is excellent in blow moldability, transparency, heat resistance, and cleanness, it can be suitably used for medical containers, food containers, cosmetic containers, and the like.

  In addition, the container obtained by the present invention conforms to the Japanese Pharmacopoeia, has excellent product appearance and transparency, can withstand sterilization at 121 ° C., and has excellent cleanliness. It is suitably used for pharmaceutical containers such as nasal drops containers and internal liquid containers. Since transparency can be maintained even after sterilization at 121 ° C., it is suitably used for medical containers such as medical infusion / infusion preparation containers, ampoule preparation containers, kit preparation containers, and eye drop containers that require particularly high transparency. be able to.

  Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples.

~resin~
Various properties of the resins used in Examples and Comparative Examples were evaluated by the following methods.

<MFR>
MFR (melt mass flow rate) was measured according to JIS K6922-1.

<Density>
The density was measured by a density gradient tube method in accordance with JIS K6922-1.

<Molecular weight, molecular weight distribution>
Weight average molecular weight (Mw), number average molecular weight (Mn), ratio of weight average molecular weight to number average molecular weight (Mw / Mn) and peak top molecular weight (Mp) were measured by GPC. The column temperature was set to 140 ° C. using a GPC device (Tosoh Corp. (trade name) HLC-8121GPC / HT) and a column (Tosoh Corp. (trade name) TSKgel GMHhr-H (20) HT). The measurement was performed using 1,2,4-trichlorobenzene as an eluent. A measurement sample was prepared at a concentration of 1.0 mg / ml, and 0.3 ml was injected and measured. The calibration curve of molecular weight was calibrated using a polystyrene sample having a known molecular weight. In addition, Mw and Mn were calculated | required as a value of linear polyethylene conversion.

<Molecular weight fractionation>
For molecular weight fractionation, a glass bead packed column (diameter: 21 mm, length: 60 cm) is used as the column, the column temperature is set to 130 ° C., and 1 g of sample dissolved in 30 mL of xylene is injected. Next, distillate is removed by using a xylene / 2-ethoxyethanol ratio of 50/50% by volume as a developing solvent. Thereafter, using xylene as a developing solvent, the components remaining in the column are distilled off to obtain a polymer solution. A molecular weight fractionation component was obtained by adding 5 times amount of methanol to the obtained polymer solution to precipitate a polymer, filtering and drying. About this component, using the above-mentioned GPC apparatus, Mn was measured and it confirmed that Mn was a component which is 100,000 or more. Further, the weight of this component was measured and divided by the weight of the sample before molecular weight fractionation to obtain the fraction (% by weight) of the fraction of Mn 100,000 or more when molecular weight fractionation was performed. In addition, when the developing solvent whose xylene ratio is less than 50 volume% is used in the ratio of xylene / 2-ethoxyethanol, it has been confirmed that Mn of the molecular weight fractionated product is 100,000 or less.

<Remaining ignition heat>
In accordance with the Japanese Pharmacopoeia stipulated by the ignition residue test method, weigh accurately 50 g of the sample, put it in a platinum dish and burn it with a gas burner, and then complete ashing in an electric furnace at 650 ° C. for 1 hour The weight of the residue was measured, and the percentage was calculated by calculating the percentage with respect to the initial weight.

<Extracted amount of n-heptane>
About 10 g of a 200 mesh pass crushed sample is precisely weighed, 400 ml of n-heptane is added, extraction is performed at 50 ° C. for 2 hours, the solvent is evaporated from the extract, and the weight of the extract obtained by drying and solidifying is measured. It was calculated by determining the percentage with respect to the initial weight.

<Long chain branching>
The number of long-chain branches was determined by 13C-NMR using a JNM-GSX400 nuclear magnetic resonance apparatus manufactured by JEOL Ltd., and the number of branches equal to or greater than the hexyl group. The solvent is benzene-d6 / orthodichlorobenzene (volume ratio 30/70). The number per 1,000 main chain methylene carbons (chemical shift: 30 ppm) was determined from the average value of the peaks of α-carbon (34.6 ppm) and β-carbon (27.3 ppm).

<Melting tension>
The sample for melt tension measurement was prepared by adding a heat-resistant stabilizer (Ciba Specialty Chemicals, Irganox 1010TM; 1,500 ppm, Irgaphos 168TM; 1,500 ppm) to an internal mixer (Toyo Seiki Seisakusho, The product kneaded for 30 minutes at 190 ° C. and 30 rpm in a nitrogen stream was used.

  To measure the melt tension, a capillary viscometer (Toyo Seiki Seisakusho, trade name Capillograph) with a barrel diameter of 9.55 mm is attached with a die with a length of 8 mm and a diameter of 2.095 mm so that the inflow angle is 90 °. It was measured. The temperature was set to 160 ° C., the piston lowering speed was set to 10 mm / min, the stretch ratio was set to 47, and the load (mN) required for take-up was the melt tension. When the maximum draw ratio was less than 47, the load (mN) required for taking-up at the highest draw ratio that did not break was taken as the melt tension.

  In Examples and Comparative Examples, resins produced by the methods described in the following Production Examples and commercially available products were used.

Production Example (1) High Density Polyethylene (A) -1
[Preparation of modified clay]
To a mixed solvent of 4.8 L of deionized water and 3.2 L of ethanol, 531 g of methyldioleylamine; (C ₁₈ H ₃₅ ) ₂ (CH ₃ ) N and 83.3 mL of 37% hydrochloric acid are added, and the methyldioleylamine hydrochloride solution is added. Prepared. To this solution, 1,000 g of synthetic hectorite was added and stirred overnight. The resulting reaction solution was filtered, and the solid was sufficiently washed with water. When the solid content was dried, 1,180 g of an organically modified clay compound was obtained. The liquid content measured with an infrared moisture meter was 0.8%. Next, this organically modified clay compound was pulverized to prepare an average particle size of 6.0 μm.
[Preparation of polymerization catalyst]
To a 5 L flask, 450 g of the organically modified clay compound obtained in the section [Preparation of modified clay compound] and 1.4 kg of hexane were added, and then 1.78 kg (1.8 mol) of a 20 wt% solution of triisobutylaluminum in hexane, Bis (indenyl) zirconium dichloride (7.06 g, 18 mmol) was added, and the mixture was heated to 60 ° C. and stirred for 1 hour. The reaction solution was cooled to 45 ° C. and allowed to stand for 2 hours, and then the supernatant was removed by a gradient method. Next, 1.78 kg (0.09 mol) of a 1% by weight hexane solution of triisobutylaluminum was added and reacted at 45 ° C. for 30 minutes. After allowing the reaction solution to stand at 45 ° C. for 2 hours, the supernatant was removed by a gradient method, 0.45 kg (0.45 mol) of a 20 wt% solution of hexane in triisobutylaluminum was added, and the whole amount was re-diluted with hexane. Was 4.5 L to prepare a polymerization catalyst.
[Production of (A) -1]
The polymerization catalyst obtained in the section of [Preparation of polymerization catalyst] was continuously fed to a polymerization vessel having an internal volume of 300 L, with hexane 135 kg / hour, ethylene 20.0 kg / hour, hydrogen 6 NL / hour, and [polymerization catalyst preparation]. Further, the co-catalyst was continuously fed so that the concentration of triisobutylaluminum in the liquid was 0.93 mmol / kg hexane. The polymerization temperature was controlled at 85 ° C. The obtained high-density polyethylene ((A) -1) had MFR = 1.0 g / 10 min and a density of 952 kg / m ³ .

(A) -2
[Preparation of modified clay]
A modified clay compound was prepared in the same manner as (A) -1.
[Preparation of polymerization catalyst]
A polymerization catalyst was prepared in the same manner as (A) -1.
[Production of (A) -2]
The polymerization catalyst obtained in the section [Preparation of polymerization catalyst] was continuously fed to a polymerization vessel having an internal volume of 300 L, with hexane 135 kg / hour, ethylene 20.0 kg / hour, hydrogen 16 NL / hour, and [preparation of polymerization catalyst]. Further, the co-catalyst was continuously fed so that the concentration of triisobutylaluminum in the liquid was 0.93 mmol / kg hexane. The polymerization temperature was controlled at 85 ° C. The obtained high-density polyethylene ((A) -2) had MFR = 6.0 g / 10 min and a density of 960 kg / m ³ .

  (A) -3: The following commercially available product was used.

Tosoh Co., Ltd., (trade name) Nipolon Hard 5700 (MFR = 1.0 g / 10 min, density = 954 kg / m ³ )
(A) -4
[Preparation of modified clay]
A modified clay compound was prepared in the same manner as (A) -1.
[Preparation of polymerization catalyst]
A polymerization catalyst was prepared in the same manner as (A) -1.
[Production of (A) -4]
Polymerization obtained in the section of “Preparation of polymerization catalyst” in a polymerization vessel having an internal volume of 300 L, hexane 135 kg / hour, ethylene 20.0 kg / hour, butene-1 0.4 kg / hour, hydrogen 8 NL / hour The catalyst was fed continuously. Further, the co-catalyst was continuously fed so that the concentration of triisobutylaluminum in the liquid was 0.93 mmol / kg hexane. The polymerization temperature was controlled at 85 ° C. The obtained high-density polyethylene ((A) -4) had an MFR of 3.0 g / 10 min and a density of 945 kg / m ³ .
(2) Linear low density polyethylene (B) -1
[Preparation of modified clay]
To 1,500 ml, 30 g of 37% hydrochloric acid and 106 g of N, N-dimethyl-behenylamine were added to prepare an aqueous solution of N, N-dimethyl-behenylammonium hydrochloride. 300 g of montmorillonite having an average particle size of 7.8 μm (manufactured by Kunimine Kogyo Co., Ltd., prepared by pulverizing trade name Kunipia F with a jet pulverizer) was added to the above hydrochloride aqueous solution and reacted for 6 hours. After completion of the reaction, the reaction solution was filtered, and the resulting cake was dried under reduced pressure for 6 hours to obtain 370 g of a modified clay compound.
[Preparation of polymerization catalyst]
To a 20 L stainless steel container under a nitrogen atmosphere, add 3.3 L of heptane, a heptane solution of triethylaluminum (diluted 20% by weight), 1.13 mol (0.9 L) per aluminum atom, and 50 g of the modified clay compound obtained above. Stir for 1 hour. Thereto was added 1.25 mmol of diphenylmethylene (4-phenyl-indenyl) (2,7-di-t-butyl-9-fluorenyl) zirconium dichloride per zirconium atom, and the mixture was stirred for 12 hours. A catalyst was prepared by adding 5.8 L of an aliphatic saturated hydrocarbon solvent (trade name IP Solvent 2835, manufactured by Idemitsu Petrochemical Co., Ltd.) to the obtained suspension system. (Zirconium concentration 0.125 mmol / L)
[Production of (B) -1]
Using a tank reactor equipped for high-temperature and high-pressure polymerization, ethylene and 1-hexene were continuously injected into the reactor so that the total pressure was 90 MPa, the 1-hexene concentration was 18 mol%, and the hydrogen concentration was 7 mol%. Was set to be. The reactor was stirred at 1,500 rpm, and the polymerization catalyst obtained as described above was continuously supplied from the supply port of the reactor, and the polymerization reaction was carried out while maintaining the average temperature at 200 ° C. The obtained linear low density polyethylene ((B) -1) had MFR = 3.5 g / 10 min and a density of 910 kg / m ³ .

(B) -2
[Preparation of modified clay]
A modified clay compound was prepared in the same manner as (B) -1.
[Preparation of polymerization catalyst]
A polymerization catalyst was prepared in the same manner as (B) -1.
[Production of (B) -2]
Using a tank reactor equipped for high-temperature and high-pressure polymerization, ethylene and 1-hexene were continuously injected into the reactor so that the total pressure was 90 MPa, the 1-hexene concentration was 18 mol%, and the hydrogen concentration was 5 mol%. Was set to be. The reactor was stirred at 1,500 rpm, and the polymerization catalyst obtained as described above was continuously supplied from the supply port of the reactor, and the polymerization reaction was carried out while maintaining the average temperature at 200 ° C. The obtained linear low-density polyethylene ((B) -2) had MFR = 2.0 g / 10 min and a density of 907 kg / m ³ .

(B) -3
[Preparation of modified clay]
A modified clay compound was prepared in the same manner as (B) -1.
[Preparation of polymerization catalyst]
A polymerization catalyst was prepared in the same manner as (B) -1.
[Production of (B) -3]
Using a tank reactor equipped for high-temperature and high-pressure polymerization, ethylene and 1-hexene were continuously injected into the reactor so that the total pressure was 90 MPa, the 1-hexene concentration was 23 mol%, and the hydrogen concentration was 1 mol%. Was set to be. The reactor was stirred at 1,500 rpm, and the polymerization catalyst obtained as described above was continuously supplied from the supply port of the reactor, and the polymerization reaction was carried out while maintaining the average temperature at 200 ° C. The obtained linear low density polyethylene ((B) -3) had MFR = 0.8 g / 10 min and a density of 900 kg / m ³ .

(B) -4
[Preparation of modified clay]
A modified clay compound was prepared in the same manner as (B) -1.
[Preparation of polymerization catalyst]
A polymerization catalyst was prepared in the same manner as (B) -1.
[Production of (B) -4]
Using a tank reactor equipped for high-temperature and high-pressure polymerization, ethylene and 1-hexene were continuously injected into the reactor so that the total pressure was 90 MPa, the 1-hexene concentration was 20 mol%, and the hydrogen concentration was 15 mol%. Was set to be. The reactor was stirred at 1,500 rpm, and the polymerization catalyst obtained as described above was continuously supplied from the supply port of the reactor, and the polymerization reaction was carried out while maintaining the average temperature at 200 ° C. The obtained linear low-density polyethylene ((B) -5) had MFR = 12 g / 10 min and a density of 907 kg / m ³ .
(B) -5: The following commercially available product was used. Tosoh Co., Ltd., (trade name) Nipolon-Z ZF220 (MFR = 2.0 g / 10 min, density = 913 kg / m ³ )
(B) -6
[Preparation of modified clay]
A modified clay compound was prepared in the same manner as (B) -1.
[Preparation of polymerization catalyst]
To a 20 L stainless steel container under a nitrogen atmosphere, add 2.5 L of heptane, a heptane solution of triethylaluminum (diluted 20 wt%), 4.5 mol (3.6 L) per aluminum atom, and 300 g of the modified clay compound obtained above. Stir for 1 hour. Diphenylmethylene (cyclopentadienyl) (2,7-di-t-butyl-9-fluorenyl) zirconium dichloride was added thereto in an amount of 10 mmol per zirconium atom, and the mixture was stirred for 12 hours. A catalyst was prepared by adding 8.7 L of an aliphatic saturated hydrocarbon solvent (trade name IP Solvent 2835, manufactured by Idemitsu Petrochemical Co., Ltd.) to the obtained suspension system. (Zirconium concentration 0.67 mmol / L).
[Production of (B) -6]
Using a tank reactor equipped for high-temperature and high-pressure polymerization, ethylene and 1-hexene were continuously injected into the reactor so that the total pressure was 90 MPa, the 1-hexene concentration was 20 mol%, and the hydrogen concentration was 4 mol%. Was set to be. And the reactor was stirred at 1,500 rpm, the polymerization catalyst obtained by the above was continuously supplied from the supply port of the reactor, and average temperature was maintained at 200 degreeC, and the polymerization reaction was performed. The obtained linear low-density polyethylene ((B) -4) had MFR = 2.5 g / 10 min and a density of 921 kg / m ³ .
(3) Ethylene polymer (C) -1
[Preparation of modified clay]
Into a 1 L flask is placed 300 mL of industrial alcohol (Japan Alcohol Sales (trade name) Echinen F-3) and 300 mL of distilled water, 15.0 g of concentrated hydrochloric acid and dimethylbehenylamine (Lion Corporation (trade name) Armin DM22D). ) 42.4 g (120 mmol) was added, heated to 45 ° C. to disperse 100 g of synthetic hectorite (Rockwood Additives (trade name) Laponite RDS), and then heated to 60 ° C. to maintain the temperature. The mixture was stirred for 1 hour. The slurry was filtered, washed twice with 600 mL of water at 60 ° C., and dried in an oven at 85 ° C. for 12 hours to obtain 122 g of organically modified clay. This organically modified clay was crushed by a jet mill to have a median diameter of 15 μm.
[Preparation of polymerization catalyst]
After a 300 mL flask equipped with a thermometer and a reflux tube was purged with nitrogen, 25.0 g of the organically modified clay obtained in (1) and 108 mL of hexane were added, and then dimethylsilylene (cyclopentadienyl) (2, 4, 4 7-trimethyl-1-indenyl) zirconium dichloride / 0.4406 g and 142 mL of 20% triisobutylaluminum were added and stirred at 60 ° C. for 3 hours. After cooling to 45 ° C., the supernatant was extracted, washed 5 times with 200 mL of hexane, and then 200 mL of hexane was added to obtain a catalyst suspension (solid weight: 11.5 wt%).
[Production of (C) -1]
To a 2 L autoclave was added 1.2 L of hexane, 1.0 mL of 20% triisobutylaluminum, and 58 mg of the catalyst suspension obtained in (2) (equivalent to a solid content of 7.0 mg), and the temperature was raised to 80 ° C. 8.3 g of 1-butene was added, and an ethylene / hydrogen mixed gas was continuously supplied so that the partial pressure became 0.85 MPa (concentration of hydrogen in the ethylene / hydrogen mixed gas: 850 ppm). After 90 minutes, the pressure was released, and the slurry was filtered and dried to obtain 49.0 g of polymer (activity: 7,000 g / g catalyst). This polymer had an MFR of 3.7 g / 10 min, a density of 939 kg / m ³ and a melting point of 125.4 ° C. The number average molecular weight was 20,304, the weight average molecular weight was 75,200, and peaks were observed at the positions of molecular weights 40,730 and 216,240. The number of long chain branches contained in the polymer is 0.06 per 1000 carbons of the main chain, and the number of long chain branches contained in the fraction of Mn of 100,000 or more when molecular weight fractionation is 1000 carbons of the main chain. The number was 0.17 per number. Moreover, the ratio of the fraction of Mn 100,000 or more when molecular weight fractionation was 14.3 wt% of the total polymer. The melt tension was 50 mN.

(C) -2
[Preparation of modified clay]
Into a 1 L flask is placed 300 mL of industrial alcohol (Japan Alcohol Sales (trade name) Echinen F-3) and 300 mL of distilled water, 17.5 g of concentrated hydrochloric acid and dimethylbehenylamine (Lion Corporation (trade name) Armin DM22D). ) 49.4 g (140 mmol) was added and heated to 45 ° C. to disperse 100 g of synthetic hectorite (Rockwood Additives (trade name) Laponite RDS) and then heated to 60 ° C. to maintain the temperature. The mixture was stirred for 1 hour. The slurry was separated by filtration, washed twice with 600 mL of water at 60 ° C., and dried in an oven at 85 ° C. for 12 hours to obtain 132 g of organically modified clay. This organically modified clay was crushed by a jet mill to have a median diameter of 15 μm.
[Preparation of polymerization catalyst]
After a 300 mL flask equipped with a thermometer and a reflux tube was purged with nitrogen, 25.0 g of the organically modified clay obtained in (1) and 108 mL of hexane were added, and then dimethylsilylene (cyclopentadienyl) (2, 4, 4 0.4406 g of 7-trimethylindenyl) zirconium dichloride and 142 mL of 20% triisobutylaluminum were added and stirred at 60 ° C. for 3 hours. After cooling to 45 ° C., the supernatant was taken out, washed 5 times with 200 mL of hexane, and then 200 mL of hexane was added to obtain a catalyst suspension (solid weight: 12.4 wt%).
[Production of (C) -2]
To a 2 L autoclave was added 1.2 L of hexane, 1.0 mL of 20% triisobutylaluminum, 52 mg (corresponding to 6.4 mg of solid content) of the catalyst suspension obtained in (2), and the temperature was raised to 70 ° C. 17.6 g of 1-butene was added, and an ethylene / hydrogen mixed gas was continuously supplied so that the partial pressure was 0.80 MPa (concentration of hydrogen in the ethylene / hydrogen mixed gas: 590 ppm). After 90 minutes, the pressure was released, and the slurry was filtered and dried to obtain 61.8 g of polymer (activity: 9,700 g / g catalyst). This polymer had an MFR of 1.6 g / 10 min, a density of 930 kg / m ³ , and a melting point of 118.3 ° C. The number average molecular weight was 17,639, the weight average molecular weight was 86,656, and peaks were observed at the molecular weights of 30,500 and 155,300. The number of long chain branches contained in the polymer is 0.14 per 1000 carbons of the main chain, and the number of long chain branches contained in the fraction of Mn of 100,000 or more when molecular weight fractionation is 1000 carbons of the main chain. The number was 0.27 per number. Moreover, the ratio of the fraction of Mn 100,000 or more when molecular weight fractionation was 20.1 wt% of the total polymer. The melt tension was 75 mN.

(C) -3
[Preparation of modified clay]
Into a 1 L flask was placed 300 mL of industrial alcohol (Japan Alcohol Sales Co., Ltd. (trade name) Echinen F-3) and distilled water (300 mL), concentrated hydrochloric acid 18.8 g and dimethylbehenylamine (Lion Corporation (trade name) Armin DM22D ) 53.0 g (150 mmol) was added and heated to 45 ° C. to disperse 100 g of synthetic hectorite (Rockwood Additives (trade name) Laponite RDS), and then heated to 60 ° C. to maintain the temperature. The mixture was stirred for 1 hour. This slurry was separated by filtration, washed twice with 600 mL of water at 60 ° C., and dried in an oven at 85 ° C. for 12 hours to obtain 135 g of an organically modified clay. This organically modified clay was crushed by a jet mill to have a median diameter of 15 μm.
[Preparation of polymerization catalyst]
After a 300 mL flask equipped with a thermometer and a reflux tube was purged with nitrogen, 25.0 g of the organically modified clay obtained in (1) and 108 mL of hexane were added, and then dimethylsilylenebis (cyclopentadienyl) zirconium dichloride was added to 0. 3485 g and 20% triisobutylaluminum 142 mL were added and stirred at 60 ° C. for 3 hours. After cooling to 45 ° C., the supernatant was extracted, washed 5 times with 200 mL of hexane, and then 200 mL of hexane was added to obtain a catalyst suspension (solid weight: 10.7 wt%).
[Production of (C) -3]
To a 2 L autoclave was added 1.2 L of hexane, 1.0 mL of 20% triisobutylaluminum, and 75 mg (corresponding to a solid content of 8.0 mg) of the catalyst suspension obtained in (2). Ethylene gas was continuously supplied so that the partial pressure was 1.20 MPa. After 90 minutes, the pressure was released, and the slurry was filtered and dried to obtain 63.2 g of polymer (activity: 7,900 g / g catalyst). The MFR of this polymer was 0.25 g / 10 min, the density was 948 kg / m ³ , and the melting point was 131.5 ° C. The number average molecular weight was 11,431, the weight average molecular weight was 43,000, and peaks were observed at molecular weights of 18,100 and 189,200. Further, the number of long chain branches contained in the polymer is 0.05 per 1000 carbons of the main chain, and the number of long chain branches contained in the fraction of Mn of 100,000 or more when molecular weight fractionation is 1000 carbons of the main chain. The number was 0.17 per number. Moreover, the ratio of the fraction of Mn 100,000 or more when molecular weight fractionation was 9.2 wt% of the total polymer. The melt tension was 95 mN.

(C) -4
[Preparation of modified clay]
Into a 1 L flask was placed 300 mL of industrial alcohol (Japan Alcohol Sales Co., Ltd. (trade name) Echinen F-3) and distilled water (300 mL), concentrated hydrochloric acid 18.8 g and dimethylbehenylamine (Lion Corporation (trade name) Armin DM22D ) 53.0 g (150 mmol) was added and heated to 45 ° C. to disperse 100 g of synthetic hectorite (Rockwood Additives (trade name) Laponite RDS), and then heated to 60 ° C. to maintain the temperature. The mixture was stirred for 1 hour. This slurry was separated by filtration, washed twice with 600 mL of water at 60 ° C., and dried in an oven at 85 ° C. for 12 hours to obtain 135 g of an organically modified clay. This organically modified clay was crushed by a jet mill to have a median diameter of 15 μm.
[Preparation of polymerization catalyst]
After a 300 mL flask equipped with a thermometer and a reflux tube was purged with nitrogen, 25.0 g of the organically modified clay obtained in (1) and 108 mL of hexane were added, and then dimethylsilylene (cyclopentadienyl) (2, 4, 4 7-trimethyl-1-indenyl) zirconium dichloride / 0.4406 g and 142 mL of 20% triisobutylaluminum were added and stirred at 60 ° C. for 3 hours. After cooling to 45 ° C., the supernatant was taken out, washed 5 times with 200 mL of hexane, and then 200 mL of hexane was added to obtain a catalyst suspension (solid weight: 11.9 wt%).
[Production of (C) -4]
To a 2 L autoclave was added 1.2 L of hexane, 1.0 mL of 20% triisobutylaluminum, and 54 mg (corresponding to 6.4 mg of solid content) of the catalyst suspension obtained in (2). 17.6 g of 1-butene was added, and an ethylene / hydrogen mixed gas was continuously supplied so that the partial pressure became 0.80 MPa (concentration of hydrogen in the ethylene / hydrogen mixed gas: 580 ppm). After 90 minutes, the pressure was released, and the slurry was filtered and dried to obtain 37.6 g of polymer (activity: 5,900 g / g catalyst). This polymer had an MFR of 0.07 g / 10 min, a density of 925 kg / m ³ and a melting point of 114.4 ° C. The number average molecular weight was 26,313, the weight average molecular weight was 146,261, and peaks were observed at the positions of molecular weights 42,800 and 260,800. The number of long chain branches contained in the polymer is 0.20 per 1000 carbons of the main chain, and the number of long chain branches contained in the fraction of Mn of 100,000 or more when molecular weight fractionation is 1000 carbons of the main chain. The number was 0.37 per number. Moreover, the ratio of the fraction of Mn 100,000 or more when molecular weight fractionation was 32.7 wt% of the total polymer. The melt tension was 150 mN.

(C) -5
[Preparation of modified clay]
Into a 1 L flask is placed 300 mL of industrial alcohol (Japan Alcohol Sales (trade name) Echinen F-3) and 300 mL of distilled water, 15.0 g of concentrated hydrochloric acid and dimethylbehenylamine (Lion Corporation (trade name) Armin DM22D). ) 42.4 g (120 mmol) was added, heated to 45 ° C. to disperse 100 g of synthetic hectorite (Rockwood Additives (trade name) Laponite RDS), and then heated to 60 ° C. to maintain the temperature. The mixture was stirred for 1 hour. The slurry was filtered, washed twice with 600 mL of water at 60 ° C., and dried in an oven at 85 ° C. for 12 hours to obtain 122 g of organically modified clay. This organically modified clay was crushed by a jet mill to have a median diameter of 15 μm.
[Preparation of polymerization catalyst]
After a 300 mL flask equipped with a thermometer and a reflux tube was purged with nitrogen, 25.0 g of the organically modified clay obtained in (1) and 108 mL of hexane were added, and then dimethylsilylene (cyclopentadienyl) (2, 4, 4 7-trimethyl-1-indenyl) zirconium dichloride / 0.4406 g and 142 mL of 20% triisobutylaluminum were added and stirred at 60 ° C. for 3 hours. After cooling to 45 ° C., the supernatant was extracted, washed 5 times with 200 mL of hexane, and then 200 mL of hexane was added to obtain a catalyst suspension (solid weight: 11.5 wt%).
[Production of (C) -5]
To a 2 L autoclave was added 1.2 L of hexane, 1.0 mL of 20% triisobutylaluminum, and 70 mg (corresponding to 8.4 mg of solid content) of the catalyst suspension obtained in (2). 2.4 g of 1-butene was added, and an ethylene / hydrogen mixed gas was continuously supplied so that the partial pressure became 0.90 MPa (hydrogen concentration in the ethylene / hydrogen mixed gas: 750 ppm). After 90 minutes, the pressure was released, and the slurry was filtered and dried to obtain 63.0 g of polymer (activity: 7,500 g / g catalyst). This polymer had an MFR of 16 g / 10 min, a density of 954 kg / m ³ , and a melting point of 135.2 ° C. Moreover, the number average molecular weight was 15,500, the weight average molecular weight was 52,700, and peaks were observed at positions of molecular weights 27,900 and 179,000. Further, the number of long chain branches contained in the polymer is 0.05 per 1000 carbons of the main chain, and the number of long chain branches contained in the fraction of Mn of 100,000 or more when molecular weight fractionation is 1000 carbons of the main chain. The number was 0.16 per number. Moreover, the ratio of the fraction of Mn 100,000 or more when molecular weight fractionation was 6.5 wt% of the total polymer. The melt tension was 35 mN.
(S) -1
[Preparation of modified clay]
Into a 1 L flask is placed 300 mL of industrial alcohol (Japan Alcohol Sales (trade name) Echinen F-3) and 300 mL of distilled water, 15.0 g of concentrated hydrochloric acid and dimethylbehenylamine (Lion Corporation (trade name) Armin DM22D). ) 42.4 g (120 mmol) was added, heated to 45 ° C. to disperse 100 g of synthetic hectorite (Rockwood Additives (trade name) Laponite RDS), and then heated to 60 ° C. to maintain the temperature. The mixture was stirred for 1 hour. The slurry was filtered, washed twice with 600 mL of water at 60 ° C., and dried in an oven at 85 ° C. for 12 hours to obtain 122 g of organically modified clay. This organically modified clay was crushed by a jet mill to have a median diameter of 15 μm.
[Preparation of polymerization catalyst]
After substituting a 300 mL flask equipped with a thermometer and a reflux tube with nitrogen, 25.0 g of the organically modified clay obtained in (1) was suspended in 165 mL of hexane, and dimethylsilylene (cyclopentadienyl) (2,4 , 7-trimethyl-1-indenyl) zirconium dichloride (0.4406 g) and triethylaluminum hexane solution (1.18 M) 85 mL were added and stirred at 60 ° C. for 3 hours. After allowing to stand and cooling to room temperature, the supernatant was taken out and washed twice with 200 mL of a 1% triisobutylaluminum hexane solution. The supernatant liquid after washing was extracted and the whole was made up to 250 mL with a 5% triisobutylaluminum hexane solution. Subsequently, it was prepared by separately adding 5 ml of a 20% triisobutylaluminum hexane solution (0.71 M) to a suspension of 0.062 g of diphenylmethylene (1-cyclopentadienyl) (9-fluorenyl) zirconium dichloride in 10 ml of hexane. The solution was added and stirred at room temperature for 6 hours. The supernatant was removed by standing, and after washing twice with 200 mL of hexane, 200 mL of hexane was added to obtain a catalyst suspension (solid weight: 12.0 wt%).
[Production of (S) -1]
To a 2 L autoclave was added 1.2 L of hexane, 1.0 mL of 20% triisobutylaluminum, and 92 mg (equivalent to 11.0 mg of solid content) of the catalyst suspension obtained in (2), and the temperature was raised to 85 ° C. 16.6 g of 1-butene was added, and ethylene was continuously supplied so that the partial pressure became 0.80 MPa. After 90 minutes, the pressure was released, and the slurry was filtered and dried to obtain 59.7 g of polymer (activity: 5,430 g / g catalyst). The polymer had an MFR of 12 g / 10 min, a density of 932 kg / m ³ and a melting point of 119.8 ° C. The number average molecular weight was 19,567, the weight average molecular weight was 74,304, and a peak was observed at a molecular weight of 35,500. The number of long chain branches contained in the polymer is 0.04 per 1000 carbons of the main chain, and the number of long chain branches contained in the fraction of Mn of 100,000 or more when molecular weight fractionation is 1000 carbons of the main chain. The number was 0.07 per number. Moreover, the ratio of the fraction of Mn 100,000 or more when molecular weight fractionation was 12.5 wt% of the total polymer. The melt tension was 15 mN.
(4) High pressure method low density polyethylene (D) -1: The following commercially available product was used.

Tosoh Co., Ltd., (trade name) Petrocene 170K (MFR = 1.0 g / 10 min, density = 921 kg / m ³ )
(D) -2: The following commercially available product was used.

Tosoh Co., Ltd., (trade name) Petrocene 173K (MFR = 0.3 g / 10 min, density = 924 kg / m ³ )
(D) -3: The following commercially available product was used.

Tosoh Co., Ltd., (trade name) Petrocene 172 (MFR = 0.3 g / 10 min, density = 920 kg / m ³ )
(D) -4: The following commercially available product was used.

(Product name) NUC2460MD (MFR = 1.0 g / 10 min, density = 927 kg / m ³ ), manufactured by Nippon Unicar Co., Ltd.
(D) -5: The following commercially available product was used.

Tosoh Co., Ltd., (trade name) Petrocene 219 (MFR = 3.0 g / 10 min, density = 934 kg / m ³ )
~ Molding and container evaluation ~
The moldability and container evaluation methods used in the examples and comparative examples are shown below.

~ Evaluation of formability ~
~ Evaluation of surface gloss ~
Using a blow molding machine (manufactured by Tahara) equipped with a 500 ml square bottle mold and a 50 mmφ extrusion screw, the evaluation resin was evaluated under conditions of a molding temperature of 210 ° C., a discharge rate of 7 kg / h, and a die gap of 1.4 mm. A 500 ml square bottle was molded. The glossiness of the surface of the obtained bottle was visually observed and evaluated.

○: The surface is smooth and the gloss is good. ×: The surface is smooth, but there is no gloss. XX: The surface is satin and has no gloss.
Using the blow molding machine (Tahara Co., Ltd.), an evaluation resin parison was extruded at a molding temperature of 210 ° C., a discharge rate of 7 kg / h, and a die gap of 1.4 mm. The time required for the parison to sag 250 mm from the lip was evaluated as the sag time.

○: Droop time 15 seconds or more ×: Droop time 10 seconds to less than 15 seconds XX: Droop time less than 10 seconds
~ Evaluation of transparency ~
Hitachi cuts a sample piece having an average thickness of 500 μm, a width of 9.5 mm, and a length of 50 mm from the container manufactured by the method described in the Examples and the body of the container after sterilization at a temperature of 121 ° C. for 20 minutes. Using a “UV-visible spectrophotometer 220A” manufactured by the company, the transmittance at a wavelength of 450 nm was measured in pure water, and the transparency before and after sterilization was evaluated. In addition, it was judged that transparency was good when the light transmittance of 55% or more was maintained after sterilization.

~ Evaluation of heat resistance ~
A container produced by the method described in the Examples was filled with 400 ml of pure water, the container was sealed with a heat seal, and set in an autoclave. In accordance with the Japanese Pharmacopoeia, after sterilizing at a temperature of 121 ° C. for 20 minutes by the high pressure steam sterilization method, the container was taken out and the appearance of the container was observed and evaluated for the following items.
Deformation: The waving state of the container was observed.

  ○: The container shape hardly changes.

  X: Deformation was seen in the container shape.

  XX: The container shape is greatly deformed.

~ Cleanliness (number of fine particles) ~
After filling and sealing the ultrapure water whose number of fine particles of 1 μm or more was confirmed to be 0/10 ml in a container manufactured by the method described in the examples, a hot water sterilization treatment was performed at 121 ° C. for 20 minutes. Then, after standing for 1 day, the number of fine particles of 1 μm or more was measured using a fine particle counter “M-3000 · 4100 · HR-60HA” manufactured by HIAC / ROYCO. These operations were all performed in a class 1000 clean room. A case where the number of fine particles was 10 / ml or less was used as a guideline for a medical container with good cleanliness.

Example 1
(1) Production of resin composition High-density polyethylene (A-1), linear low-density polyethylene (B-1), ethylene polymer (C-1), and high-pressure low-density polyethylene obtained in Production Examples (D-1) is dry blended at a ratio of 20: 20: 35: 25 (parts by weight), melt-extruded into a strand shape using a 50 mm diameter single-screw extruder manufactured by Placo Corporation, and pelletized using a pelletizer. Granulation was performed. The barrel temperature was C1; 180 ° C., C2; 200 ° C., C3; 220 ° C., die head: 220 ° C.

(2) Manufacture of containers Using a blow molding machine (made by Tahara) equipped with a 500 ml square bottle mold and a 50 mmφ extrusion screw, a molding temperature of 180 ° C., a discharge rate of 7.0 kg / h, a die gap of 1 A 500 ml square bottle of the evaluation resin was molded under the condition of 4 mm. The average wall thickness of the bottle body was 500 μm. The results are shown in Table 1.

Examples 2-14
Examples except that the types and blend ratios of high density polyethylene (A), linear low density polyethylene (B), ethylene polymer (C), and high pressure method low density polyethylene (D) were changed as shown in Table 1. 1 was performed. The results are shown in Table 1.

比較例１〜１０
高密度ポリエチレン（Ａ）と直鎖状低密度ポリエチレン（Ｂ）とエチレン系重合体（Ｃ）又は（Ｓ）と高圧法低密度ポリエチレン（Ｄ）の種類及びブレンド比率を表２のように変えた以外は実施例１と同様に行った。結果を表２に示す。

Comparative Examples 1-10
Table 2 shows the types and blend ratios of high-density polyethylene (A), linear low-density polyethylene (B), ethylene polymer (C) or (S), and high-pressure method low-density polyethylene (D). Except for this, the same procedure as in Example 1 was performed. The results are shown in Table 2.

Claims (6)

20 to 30 parts by weight of high density polyethylene (A) satisfying the following characteristics (a) to (b), 20 to 40 parts by weight of linear low density polyethylene (B) satisfying the following characteristics (c) to (d) 25 to 35 parts by weight of an ethylene polymer (C) satisfying the following characteristics (e) to (h), 5 to 25 weight of a high-pressure low-density polyethylene (D) satisfying the following characteristics (i) to (j) Part (the sum of (A), (B), (C) and (D) is 100 parts by weight).
(A) The density is from 950 to 970 kg / m ³ .
(B) The melt mass flow rate (hereinafter referred to as MFR) measured at a temperature of 190 ° C. and a load of 21.18 N in accordance with JIS K6924-1 is 0.1 to 10 g / 10 minutes.
(C) The density is 890 to 915 kg / m ³ .
(D) MFR is 0.1-10 g / 10min.
(E) The density is 930-949 kg / m ³ .
(F) MFR is 0.1-10 g / 10min.
(G) Two peaks are shown in the molecular weight measurement by gel permeation chromatography, and the ratio (Mw / Mn) of the weight average molecular weight (Mw) to the number average molecular weight (Mn) is in the range of 2.0 to 7.0. It is.
(H) The fraction having a Mn of 100,000 or more when molecular weight fractionation has 0.15 or more long-chain branches having a hexyl group or more per 1000 carbons of the main chain.
(I) The density is from 918 to 925 kg / m ³ .
(J) MFR is 0.1 to 2.0 g / 10 min.   A container comprising the polyethylene resin composition according to claim 1.   The container according to claim 2, wherein the light transmittance measured at a wavelength of 450 nm in pure water after sterilization at 121 ° C is 55% or more.   The container according to any one of claims 2 and 3, wherein the container is a medical container including at least a container for storing a chemical solution.   The container according to any one of claims 2 to 4, wherein the container is one selected from the group consisting of an infusion preparation container, an ampoule preparation container, a kit preparation container, and an eye drop container.   The blow molded container according to any one of claims 2 to 5.