JPH08113678A - High-purity chemical container - Google Patents

Abstract

PURPOSE: To provide a high-purity chemical container which has an excellent mechanical strength, an easy handleability, barrier properties and light- interceptive properties, and has very little particulate impurities thereof oozed into a chemical stored therein. CONSTITUTION: This container is made from a resin compsn. comprising a polyethylene or ethylene-α-olefin copolymer resin having a density of 0.940 to 0.970g/cm<3> and at least a light-interceptive compsn. and a barrier compsn. added thereto. The resin has a wt.-average mol.wt. of 12×10<4> to 26×10<4> as measured by gel permeation chromatography, and contains less than 5wt.% polymer having a mol.wt. of at most 1×10<3> . The α-olefin is at least one member selected from among propylene, butene-1, 4-methylpentene-1, hexane-1, and octane-1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a container used for storing high purity chemicals.

[0002]

2. Description of the Related Art Generally, a glass container or a plastic container is used as a container for storing chemicals and the like.

In the field of semiconductors, it is necessary that stored high-purity chemicals can be stored in high purity. Many chemicals undergo a loss due to the permeation of the content liquid through the container, a deterioration due to the invasion of outside gas, or a long-term exposure to light. For this reason, it is preferable that the container for storing the drug has a barrier property and a light-shielding property in order to prevent deterioration and keep the quality constant from the production to the consumption of the drug.

A colored glass container is widely used as such a container. The colored glass container is characterized in that the impure fine particles are less leached from the container into the chemical by selecting the material. However, since the container itself is heavy, it is inconvenient to handle and may be broken due to dropping or the like.

On the other hand, Japanese Patent Publication No. 60-14695 discloses a molded container having a high barrier property and mechanical strength, which is composed of a mixture of a polyolefin, a polymer incompatible with the polyolefin, and a polyolefin having a carboxyl group. There is.

However, high-purity solvent-based resists and diluting solvents used for semiconductor processes, liquid crystal displays, etc., such as methyl alcohol, ethyl alcohol, isopropyl alcohol, isobutyl alcohol,
Ethylene glycol, acetone, ethyl acetate, toluene, dimethylformamide, ethylene glycol acetate, methoxypropyl acetate, butyl cellosolve, etc., and high-purity chemicals used for pharmaceuticals such as sterilization, disinfection, and drug substance, for example, methyl alcohol, ethyl alcohol During storage and storage of isopropyl alcohol, etc., impure fine particles are leached from the resin composition and additives forming the container into the stored chemicals, and the chemicals are altered by light, impairing the purity. . Therefore, there are problems that the quality and yield of semiconductors and liquid crystals are significantly adversely affected, and the storage period of chemicals is shortened.

[0007] Further, during storage of the chemical in the container for a long period of time, cleanliness is an index indicating the degree to which the impure fine particles are leached from the resin composition forming the container into the chemical to impure the chemical. There is that. The degree of cleanliness is determined by molding an inspection container, storing ultrapure water in the inspection container for a certain period of time, and then determining how many fine particles with a particle size of 0.2 μm or more are present in 1 ml of water stored in the resin container. Calculate and obtain. Specifically, it is defined by the following equation.

[0008]

[Equation 1]

In the formula (1), a is the capacity of the container to be inspected, and b
Is the amount of ultrapure water sampled from the container to be inspected. Sampling water is collected as follows. Half of the volume, a / 2 (ml), of ultrapure water is put in a container to be inspected having a volume of aml, shaken for 15 seconds each time to be discharged, and the inside of the container is washed. After repeating shaking and washing 5 times, put a / 2 (ml) of ultrapure water into the a (ml) container again, leave it at room temperature for 1 week, shake it for another 15 seconds, and shake it in the container. Let water stand for 20 minutes. Sampling water is taken from the water that has been allowed to stand for 20 minutes. c is a value obtained by counting fine particles having a particle size of 0.2 μm or more contained in the total amount of sampling water with a particle counter. The cleanliness is calculated by the equation (1) based on the numerical value. When the cleanliness is less than 500 pieces / ml, the quality and yield of semiconductors and liquid crystals can be improved.

A container for storing high-purity chemicals cannot be used unless it has a low degree of cleanliness and a light-shielding property and a barrier property. A container formed by adding a barrier composition to a conventional polyethylene-based resin has a high cleanness value and is inferior in light-shielding property. Further, the container formed by adding the light-shielding pigment and the pigment dispersant has a very high degree of cleanliness and cannot be used as a container for high-purity chemicals.

[0011]

DISCLOSURE OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and it has excellent mechanical strength, is easy to handle, and prevents leaching of impure fine particles into stored chemicals. It is an object of the present invention to provide a container for high-purity chemicals that has extremely few barrier properties and light-shielding properties.

[0012]

As a result of earnest research in view of the above object, in producing a container for high-purity chemicals, the weight average molecular weight of a raw material resin is in a certain range, and a light-shielding pigment in a resin composition and The content of the barrier composition is within a certain range, and by controlling the content of the low molecular weight polymer, the pigment dispersant and the additive in the resin composition to less than a certain weight, excellent mechanical strength and filling can be achieved. The inventors have found that a container for high-purity chemicals can be obtained which has a barrier property and a light-shielding property, in which leaching of fine particle impurities into the chemicals is extremely small, and the present invention has been completed.

That is, the container for high-purity chemicals of the present invention is
A container for high-purity chemicals comprising a resin composition in which a light-shielding pigment, a pigment dispersant and a barrier composition are added to a resin of polyethylene or an ethylene / α-olefin copolymer having a density of 0.940 to 0.970 g / cm ^3. And the weight average molecular weight of the resin measured by gel permeation chromatography (GPC) is 12 to 26 × 10 ⁴ , and the molecular weight is 1
Polymers of × 10 ³ or less are less than 5% by weight of the resin, each content of the neutralizing agent, antioxidant and light stabilizer in the resin composition quantified by liquid chromatography of the resin composition. It is 0.1% by weight or less.

The α-olefin copolymerized with ethylene is
Propylene, butene-1, 4-methyl-pentene-1,
Hexene-1 and octene-1 are used. The content of α-olefin in the copolymer is preferably 15% by weight or less.
The molecular structure of the copolymer may be atactic, isotactic or syndiotactic. The polymerization method may be either a low pressure method or an intermediate pressure method.

Examples of the light-shielding pigment include inorganic pigments of titanium oxide, carbon black and red iron oxide, phthalocyanine type pigments, quinacridone type pigments and azo type organic pigments. The content of the light-shielding pigment is preferably 0.01 to 5% by weight based on the resin composition. If the content of the light-shielding pigment is less than 0.01% by weight with respect to the resin composition, a sufficient light-shielding effect cannot be obtained, and if it exceeds 5% by weight, the cleanliness exceeds 500 pieces / ml, and it is suitable for high-purity chemical containers. Not suitable.

Examples of the pigment dispersant include olefin polymers of polyethylene and polypropylene. The number average molecular weight of the pigment dispersant added to obtain a high degree of dispersion of the pigment is 2 × 10 ³ or more, and the content of the pigment dispersant is less than 5% by weight based on the resin composition. Is preferred.
The number average molecular weight of the pigment dispersant measured by GPC is 2
It is less than × 10 ³ , or the pigment dispersant content is 5% by weight.
If it exceeds, the cleanliness will exceed 500 pieces / ml, which is not suitable for high-purity chemical containers.

The barrier composition is a mixture of at least one selected from polyamide, polyvinyl alcohol, poly (ethylene-co-vinyl alcohol) and a polyolefin having a carboxyl group, for example, commercially available Sealer RB series (Dupont Manufactured by the company). The content of the barrier composition is 4% by weight based on the resin composition
It is preferably ˜25% by weight. If the content of the barrier composition is less than 4% by weight with respect to the resin composition, sufficient barrier properties cannot be obtained, and if it exceeds 25% by weight, the cleanliness is low.
Over 500 pieces / ml, not suitable for high-purity chemical containers.

The neutralizing agent is not necessary when the polymerization method is the medium pressure method, and is used as a chlorine catcher when the polymerization method is the low pressure method. Examples of the neutralizing agent include stearates of alkaline earth metals such as calcium, magnesium and barium, but it is necessary to minimize the amount of these by operations such as increasing the activity of the catalyst in the polymerization step. If the content of the neutralizing agent exceeds 0.1% by weight with respect to the resin composition, the cleanliness will exceed 500 pieces / ml and the quality and yield of semiconductors and liquid crystals will be deteriorated. For things
It should be 0.1% by weight or less.

Antioxidants include dibutylhydroxytoluene, pentaerythyl-tetrakis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate], octadecyl-3- (3,5-di-). t-butyl-
4-hydroxyphenyl) propionate phenolic antioxidants can be mentioned, and for the same reason as the above-mentioned neutralizing agent, the content of the antioxidant must be 0.1% by weight or less based on the resin composition.

As the light resistance stabilizer, 2- (5-methyl-
2-hydroxyphenyl) benzotriazole, 2-
(3-t-Butyl-5-methyl-2-hydroxyphenyl) -5-chlorobenzotriazole benzotriazole-based light stabilizer, bis (2,2,6,6-tetramethyl-4-piperidine) sebacate, poly [{6- (1,
1,3,3-tetramethylbutyl) amino-1,3,5
-Triazine-2,4-diyl} (2,2,6,6-
Tetramethyl-4-piperidyl) imino} hexamethylene {(2,2,6,6-tetramethyl-4-piperidyl) imino}] hindered amine-based light fastness stabilizers may be mentioned, which are similar to the neutralizing agent. For the reason, the content of the light resistance stabilizer needs to be 0.1% by weight or less based on the resin composition.

As the additive, a catalyst is used in a predetermined amount in the polymerization, but a neutralizing agent, an antioxidant, a light resistance stabilizer,
The light-shielding pigment and the pigment dispersant are eluted from the container into the chemical and cause impure fine particles, so that the addition amount is important.

The content of additives contained in the resin composition is
Using tetrahydrofuran (THF) for the resin composition,
It is the value obtained by separating and quantifying the extract liquid extracted by the Soxhlet extractor for 8 hours by liquid chromatography. The measuring conditions are as follows: apparatus is GULLIVER (manufactured by JASCO Corporation), column is Finepak GEL 101 (manufactured by JASCO Corporation), solvent is THF, and detector is UV-97.
0 (manufactured by JASCO Corporation) and 830-RI (manufactured by JASCO Corporation).

The high-purity chemical container of the present invention is manufactured, for example, by the following method. A resin composition obtained by adding a light-shielding pigment, a pigment dispersant and a barrier composition to polyethylene or an ethylene / α-olefin copolymer having a density of 0.940 to 0.970 g / cm ³ is melt-extruded. At this time, the additive contained in the resin composition, that is, the content of the neutralizing agent, the antioxidant and the light stabilizer is 0.1% with respect to the resin composition.
Reduce to less than weight%. The amount of the light-shielding pigment added is 0.01 to 5% by weight based on the resin composition, and the pigment dispersant comprising an olefin polymer has a number average molecular weight of 2 × 10 ³ or more, and the content of the pigment dispersant in the resin composition is On the other hand, it is less than 5% by weight, and the amount of the barrier composition added is 4% by weight to 25% with respect to the resin composition.
Weight%

The method of mixing the light-shielding pigment, the pigment dispersant, the barrier composition, and the additive with the resin is not particularly limited.
For example, a method of directly adding in a pelletizing step after polymerization, or a method of preparing a high-concentration master batch in advance and dry-blending this at the time of molding can be mentioned.

When preparing a masterbatch of additives and light-shielding pigments, the base resin has a weight average molecular weight of 12 to 26 × 10 ⁴ , and a polymer having a molecular weight of 1 × 10 ³ or less is used as the base resin. It is necessary to use less than 5% by weight of. In particular, when blending a light-shielding pigment, a masterbatch is often used because it is easy to change not only the light-shielding performance but also the appearance and design. Examples of the masterbatch manufacturing device include a Banbury mixer, a mixing roll and other special mixers, and the Banbury mixer is most often used.

In the case of a light-shielding pigment having a relatively good dispersibility such as carbon black or titanium oxide, a masterbatch can be obtained by dispersing and blending the powder material of the base resin and the light-shielding pigment in a biaxial kneader. it can. Even when the masterbatch is prepared, it is possible to add the neutralizing agent, the antioxidant and the light resistance stabilizer within the range of not more than 0.1% by weight of the resin composition.

The extruder used for melt extrusion molding may be an ordinary single-screw extruder, and any screw may be used as long as it gives an appropriate shearing force. However, the screen and breaker plate are not used. The resin composition is melted by an extruder and extruded into a cylindrical parison, the extruded parison is sandwiched between molds, a pressurized gas is blown from a blow pin to cool and mold.

In the obtained container, the weight average molecular weight of the container measured by GPC is 12 to 26 × 10 ⁴ , and the molecular weight is 1
It is important that the content of x10 ³ or less is controlled to less than 5% by weight of the resin.

The method for measuring the molecular weight of the container is to dissolve the resin composition cut out from the container in a solvent (orthodichlorobenzene) to prepare a sample solution, and measure the molecular weight and the molecular weight distribution by GPC. The molecular weight of the pigment dispersant is similarly measured.
The weight average molecular weight and the number average molecular weight are calculated by the following formulas. Weight average molecular weight = Σ (M × w) / Σw (2) Number average molecular weight = Σw / Σ (w / M) (3) where M is the molecular weight and w is the weight fraction.

The measurement conditions of GPC are as follows:
V (manufactured by Waters), column is TSKgel GM
H-HT (manufactured by Tosoh Corporation), the solvent is ortho-dichlorobenzene, the temperature is 138 ° C., and the detector is a differential refractometer. In order to control the molecular weight distribution of the container within the above range,
The raw material resin must also have a certain range of molecular weight distribution.

When the weight average molecular weight of the raw material resin is less than 12 × 10 ⁴ , it is generally difficult to reduce the amount of the polymer having a molecular weight of 1 × 10 ³ or less to less than 5% by weight of the resin. Even if a resin is obtained by devising a polymerization method, it will be a resin with a very narrow molecular weight distribution or a resin with a high molecular weight distribution that is biased toward the high molecular weight side.To mold this resin, increase the molding temperature or increase the shear stress. Therefore, the moldability is extremely deteriorated.

When the weight average molecular weight of the raw material resin exceeds 26 × 10 ⁴ , since the melt viscosity of the resin is high, molecular scission due to shear stress is unavoidable, and a polymer having a molecular weight of 1 × 10 ³ or less is added to 5 weight% of the resin. It cannot be kept below%.

The weight average molecular weight of the raw material resin is 12 to 26 × 10 ^4.
Even in the case of a resin in which the polymer having a molecular weight of 1 × 10 ³ or less is 5% by weight or more of the resin in order to improve the moldability, a polymer having a molecular weight of 1 × 10 ³ or less of the molded container is used as a resin. 5% by weight
It cannot be suppressed to less than the above value, and the same applies to a molding method that gives excessive shear stress.

As described above, when the polymer having a molecular weight of 1 × 10 ³ or less is 5% by weight or more of the container, impure fine particles are leached into the chemical and the cleanliness becomes 500 pieces / ml or more. Cannot be used. In addition to the blow molding described above, the molding method may be inflation molding or the like.

[0035]

The container for high-purity chemicals of the present invention is prepared by dry blending a light-shielding pigment, a pigment dispersant and a barrier composition with a resin of polyethylene or an ethylene / α-olefin copolymer, and appropriately blending under suitable conditions. It can be molded by a usual single-screw extruder equipped with a screw that gives a large shearing force. Therefore, it is possible to inexpensively obtain a high-purity chemical container having a barrier property and a light-shielding property.

[0036]

EXAMPLES Examples of the present invention will be described in detail below. Example 1 A neutralizing agent, an antioxidant, which was composed of a polymer having a density of 0.956 g / cm ³ , a weight average molecular weight of 15.0 × 10 ⁴ , and a molecular weight of 1 × 10 ³ or less and containing 1.54% by weight of a low pressure method. And 100 parts by weight of polyethylene pellets without light stabilizer, with 15.1% by weight of the same polyethylene resin as the base resin as the base resin, 3.5% by weight of titanium oxide and 0.3% by weight of carbon black as a light-shielding pigment, and a pigment dispersant. With a density of 0.95 g / cm ³ and a number average molecular weight of 3 × 10 ³ polyethylene 1.7
%, Nylon 6/66 copolymer resin 63.5% by weight and a maleic anhydride-modified polyethylene 15.9% by weight as a barrier composition were added, and 17 parts by weight of a master batch prepared by a single-screw extruder was dry blended, 50m / m,
It was melted at 230 ° C. in an extruder having L / D = 22 (D: screw diameter, L: effective screw length) and extruded into a cylindrical parison. The extruded parison was sandwiched between molds, compressed air of 6 kg / cm ² was blown from a blow pin, and cooled with a mold cooled to 20 ° C. to mold a round container having a capacity of 1000 ml and a weight of 100 g. The weight average molecular weight of the molded container resin composition is
Polymer having a molecular weight of 1 × 10 ³ or less at 14.8 × 10 ⁴ was 1.58% by weight of the resin composition. Table 1 shows the characteristics of the resin composition of the container and the addition amount condition, and Table 2 shows the constitution of the masterbatch.

Next, the cleanliness of the molded container was measured. Ultrapure water (mold name: Trepure LV-10T)
(Manufactured by Toray Industries, Inc.) was added, and the mixture was washed by shaking for 15 seconds and drained. This shaking wash was repeated 5 times. Collect 5 ml from the 5th wash water and count the number of 0.2 μm or more fine particles leached into it with a particle counter (type: KL
-22 (manufactured by Rion Co., Ltd.)). The number of fine particles in water (particles / ml) was calculated by the following equation (4) similar to equation (1). The results are shown in Table 2.

[0038]

[Equation 2]

Put 500 ml of ultrapure water into the molding container again and
Shake for 2 seconds and let stand at room temperature for 1 week. Leave the water for one week and shake it again for 15 seconds, then
Let stand for 20 minutes. 5 ml was collected from the water left to stand for 20 minutes, and the number of fine particles in water (pieces / ml) was calculated in the same manner as above. The results are shown in Table 2. After one week, the number of fine particles in water was 200 particles / ml or less, which proved to be extremely clean.

[0040]

[Table 1]

[0041]

[Table 2]

Next, the body of this container is 1 × 4 cm square and has a thickness
Cut out 1.36mm and put into a spectrophotometer (type: Ubest-
55 (manufactured by JASCO Corporation), and the absorbance at a wavelength of 600 to 200 nm was measured. The absorbance at 400 nm is 7.0 (transmittance 10 ^-5
%), Indicating an extremely good light-shielding property.

Example 2 A polymer having a density of 0.951 g / cm ³ , a weight average molecular weight of 15.2 × 10 ⁴ , and a molecular weight of 1 × 10 ³ or less, 1.37% by weight, was prepared by a medium pressure method, and dibutylhydroxytoluene was added. Example 1 was added to 100 parts by weight of polyethylene pellets containing 0.02% by weight.
17 parts by weight dry blend of the same masterbatch as
Melt to 230 ° C. in an extruder similar to Example 1 and give a volume of 100
A round container of 0 ml and weight of 100 g was molded. The molded container resin composition has a weight average molecular weight of 15.0 × 10 ⁴ , and a molecular weight of 1 × 10 4.
^{The amount} of the polymer of ³ or less was 1.40% by weight of the resin composition. Table 1 shows the characteristics of the resin composition of the container and the addition amount condition, and Table 2 shows the constitution of the masterbatch.

The cleanliness of the molded container immediately after washing five times and after one week was measured in the same manner as in Example 1, and the results are shown in Table 2. After one week, the number of fine particles in water was 200 particles / ml or less, which proved to be extremely clean.

Next, the body of this container is 1 × 4 cm square and has a thickness
1.36 mm is cut out and the wavelength is 600 to 200 in the same manner as in Example 1.
The absorbance at nm was measured. Absorbance at 400 nm is 7.0 (transmittance
10 ^-5 %), showing a very good light-shielding property.

Example 3 100 parts by weight of polyethylene pellets similar to Example 1 were added,
A density of 0.955 g / cm ³ , a weight average molecular weight of 15.2 × 10 ⁴ , and a molecular weight of 1 × 10 ³ or less 1.37% by weight. A base resin made of a polymer by the medium pressure method. % And carbon black 0.3% by weight, and nylon 6/66 copolymer resin 63.5 as a barrier composition
% And maleic anhydride-modified polyethylene 15.9% by weight were added, 17 parts by weight of a masterbatch prepared by a single-screw extruder was dry blended, and melted at 230 ° C. in the same extruder as in Example 1, A round container having a capacity of 1000 ml and a weight of 100 g was formed. The weight average molecular weight of the molded container resin composition was 14.7 × 10 ⁴ , and the polymer having a molecular weight of 1 × 10 ³ or less was 1.62% by weight of the resin composition. Table 1 shows the characteristics of the resin composition of the container and the addition amount condition, and Table 2 shows the constitution of the masterbatch.

The cleanliness of the molded container immediately after washing five times and after one week was measured in the same manner as in Example 1, and the results are shown in Table 2. After one week, the number of fine particles in water was 300 particles / ml or less, which proved to be extremely clean.

Next, the body of this container is 1 × 4 cm square and has a thickness
1.31 mm is cut off, and wavelength is 600 to 200 in the same manner as in Example 1.
The absorbance at nm was measured. Absorbance at 400 nm is 7.0 (transmittance
10 ^-5 %), showing a very good light-shielding property.

Example 4 Density of 0.957 g / cm ³ , weight average molecular weight of 20.7 × 10 ⁴ , molecular weight of 1 × 10 ³ or less, 1.43% by weight of a polymer prepared by a low pressure method. 100 parts by weight of polyethylene pellets containing no antioxidant and light stabilizer were dry blended with 17 parts by weight of the same masterbatch as in Example 1, melted at 235 ° C. in the same extruder as in Example 1, A round container having a capacity of 1000 ml and a weight of 100 g was formed. The molded container resin composition has a weight average molecular weight of 20.5 × 10 ⁴ and a molecular weight of 1
The amount of the polymer having a concentration of × 10 ³ or less was 1.44% by weight of the resin composition. Table 1 shows the characteristics of the resin composition of the container and the addition amount condition, and Table 2 shows the constitution of the masterbatch.

The cleanliness of the molded container immediately after washing five times and after one week was measured in the same manner as in Example 1, and the results are shown in Table 2. After one week, the number of fine particles in water was 200 particles / ml or less, which proved to be extremely clean.

Next, the body of this container is 1 × 4 cm square and has a thickness
1.41 mm is cut off, and wavelength is 600 to 200 in the same manner as in Example 1.
The absorbance at nm was measured. Absorbance at 400 nm is 7.0 (transmittance
10 ^-5 %), showing a very good light-shielding property.

Comparative Example 1 Density of 0.951 g / cm ³ , weight average molecular weight of 15.2 × 10 ⁴ , molecular weight of 1 × 10 ³ or less, 1.37% by weight of a polymer containing a neutralizing agent, Polyethylene pellets containing no antioxidant and light stabilizer were melted at 178 ° C. in the same extruder as in Example 1 to form a round container having a capacity of 1000 ml and a weight of 100 g. The molded container resin composition had a weight average molecular weight of 15.1 × 10 ⁴ , and a polymer having a molecular weight of 1 × 10 ³ or less was 1.38% by weight of the resin composition. Table 1 shows the characteristics of the resin composition of the container and the conditions for the amount added.

The cleanliness of the molded container immediately after washing five times and after one week was measured in the same manner as in Example 1, and the results are shown in Table 2. After one week, the number of fine particles in water was 200 particles / ml or less, which proved to be extremely clean.

Next, the body of this container is 1 × 4 cm square and has a thickness
Cut out 1.33 mm, and in the same manner as in Example 1, set a wavelength of 600 to 200.
The absorbance at nm was measured. Absorbance at 400 nm is 2.0 (transmittance
10 ^0%), it did not show sufficient light-shielding property.

Comparative Example 2 100 parts by weight of the same polyethylene pellets as in Example 1 were added,
In the masterbatch of Example 1, the pigment dispersant was added
Example 1 was prepared by dry blending 17 parts by weight of a masterbatch made of polyethylene having 0.92 g / cm ³ and a number average molecular weight of 1 × 10 ^3.
It was melted at 230 ° C. in the same extruder as described above, and a round container having a capacity of 1000 ml and a weight of 100 g was formed. The weight average molecular weight of the molded container resin composition was 14.8 × 10 ⁴ , and the polymer having a molecular weight of 1 × 10 ³ or less was 2.55% by weight based on the resin composition. Table 1 shows the characteristics of the resin composition of the container and the addition amount condition, and Table 2 shows the constitution of the masterbatch.

The cleanliness of the molded container immediately after washing five times and after one week was measured in the same manner as in Example 1, and the results are shown in Table 2. The number of fine particles in water after 1 week is 10,000 / ml
From the above, it was found that a large amount of fine particles were leached.

Next, the body of this container is 1 × 4 cm square and has a thickness
Cut out 1.41mm, same as in Example 1, wavelength 600 ~ 200nm
The absorbance of was measured. The absorbance at 400 nm is 7.0 (transmittance 10
^-5 %), showing a very good light-shielding property.

Comparative Example 3 100 parts by weight of the same polyethylene pellets as in Example 1 were added,
7.1% by weight of titanium oxide and 0.6% by weight of carbon black as a light-shielding pigment, and a density of 0.93 g / cm as a pigment dispersant.
³ , polyethylene with a number average molecular weight of 2.8 × 10 ⁴ 34.8% by weight
And 46.0% by weight of nylon 6/66 copolymer resin as a barrier composition and maleic anhydride-modified polyethylene 1
23.5 parts by weight of a master batch prepared by a single-screw extruder was added to 1.5% by weight, and the mixture was melt-blended at 230 ° C. in the same extruder as in Example 1, and the volume was 1000 ml and the weight was 1.
A round container of 00 g was molded. The molded container resin composition had a weight average molecular weight of 14.7 × 10 ⁴ , and a polymer having a molecular weight of 1 × 10 ³ or less was 2.47% by weight based on the resin composition. Table 1 shows the characteristics of the resin composition of the container and the addition amount condition, and Table 2 shows the constitution of the masterbatch.

The cleanliness of the molded container immediately after washing five times and after one week was measured in the same manner as in Example 1, and the results are shown in Table 2. The number of fine particles in water after 1 week is 10,000 / ml
From the above, it was found that a large amount of fine particles were leached.

Next, the body of this container is 1 × 4 cm square, and the thickness is
1.44 mm is cut off, and wavelength is 600 to 200 in the same manner as in Example 1.
The absorbance at nm was measured. Absorbance at 400 nm is 7.0 (transmittance
10 ^-5 %), showing a very good light-shielding property.

Comparative Example 4 100 parts by weight of the same polyethylene pellets as in Example 1 were added,
In the masterbatch of Example 1, 17 parts by weight of a masterbatch containing 0.04% by weight of zinc stearate and 0.08% by weight of polyoxyethylene fatty acid amide as a pigment dispersant were dry blended, and in the same extruder as in Example 1. 230 ° C
Then, a round container having a capacity of 1000 ml and a weight of 100 g was molded. The weight average molecular weight of the molded container resin composition is 14.9 ×
A polymer having a molecular weight of 1 × 10 ³ or less at 10 ⁴ is 1.55 of the resin composition.
% By weight. Table 1 shows the characteristics of the resin composition of the container and the addition amount condition, and Table 2 shows the constitution of the masterbatch.

The cleanliness of the molded container immediately after washing five times and after one week was measured in the same manner as in Example 1, and the results are shown in Table 2. The number of fine particles in water after 1 week is 10,000 / ml
From the above, it was found that a large amount of fine particles were leached.

Next, the body of this container is 1 × 4 cm square and has a thickness
1.27 mm is cut out, and wavelength is 600 to 200 in the same manner as in Example 1.
The absorbance at nm was measured. Absorbance at 400 nm is 7.0 (transmittance
10 ^-5 %), showing a very good light-shielding property.

[0064]

As described above in detail, the container for high-purity chemicals of the present invention has excellent mechanical strength, is easy to handle, and has very little leaching of impure fine particles into the stored chemicals. Moreover, the external gas does not enter and the internal solution does not pass through the container, so that it is possible to prevent the content liquid from being deteriorated by light or external gas intrusion. Therefore, it can be widely used as a chemical container for semiconductor chemicals and pharmaceuticals.

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[Procedure amendment]

[Submission date] September 28, 1995

[Procedure Amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0017

[Correction method] Change

[Correction content]

The barrier composition, polyamides, polyvinyl alcohol, poly mixture of polyolefins having at least one carboxyl group selected from among (ethylene - - co-vinyl alcohol), For example a commercially available sealer RB series (DuPont Manufactured by the company). The content of the barrier composition is 4% by weight based on the resin composition
It is preferably ˜25% by weight. If the content of the barrier composition is less than 4% by weight with respect to the resin composition, sufficient barrier properties cannot be obtained, and if it exceeds 25% by weight, the cleanliness is low.
Over 500 pieces / ml, not suitable for high-purity chemical containers.

[Procedure Amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0020

[Correction method] Change

[Correction content]

As the light resistance stabilizer, 2- (5-methyl-
2-hydroxyphenyl) benzotriazole, 2-
(3-t-Butyl-5-methyl-2-hydroxyphenyl) -5-chlorobenzotriazole benzotriazole-based light stabilizer, bis (2,2,6,6-tetramethyl-4-piperidine) sebacate, poly [{6- (1,
1,3,3-tetramethylbutyl) amino-1,3,5
-Triazine-2,4-diyl} (2,2,6,6-
Tetramethyl-4-piperidyl) imino} hexamethylene {(2,2,6,6-tetramethyl-4-piperidyl) imino}] hindered amine- based light stabilizers are mentioned, and for the same reason as the neutralizing agent. The content of the light resistance stabilizer must be 0.1% by weight or less based on the resin composition.

[Procedure 3]

[Document name to be amended] Statement

[Name of item to be corrected] 0024

[Correction method] Change

[Correction content]

The method of mixing the light-shielding pigment, the pigment dispersant, the barrier composition, and the additive with the resin is not particularly limited.
For example, a method of adding directly after polymerization of the pelletizing process, to create a pre <br/> Me high concentration master batch, straight them during molding
Dry-blending method and combination of the above methods
And a method of mixing .

[Procedure amendment 4]

[Document name to be amended] Statement

[Name of item to be corrected] 0025

[Correction method] Change

[Correction content]

When a masterbatch of the composition to be mixed is prepared, the base resin has a weight average molecular weight of 12 to 26 × 10 ⁴ , and a polymer having a molecular weight of 1 × 10 ³ or less is used as the resin. It is necessary to use less than wt%. In particular, when blending a light-shielding pigment, a masterbatch is often used because it is easy to change not only the light-shielding performance but also the appearance and design. Examples of the masterbatch manufacturing device include a Banbury mixer, a mixing roll and other special mixers, and the Banbury mixer is most often used.

[Procedure Amendment 5]

[Document name to be amended] Statement

[Correction target item name] 0026

[Correction method] Change

[Correction content]

In the case of a material having a relatively good dispersibility such as carbon black or titanium oxide , a twin-screw kneader or a single-screw extruder is used.
The base resin and light-shielding pigments, pigment dispersants and
A masterbatch can be obtained by blending the rear composition . Even when the masterbatch is prepared, it is possible to add the neutralizing agent, the antioxidant and the light resistance stabilizer within the range of not more than 0.1% by weight of the resin composition.

[Procedure correction 6]

[Document name to be amended] Statement

[Correction target item name] 0031

[Correction method] Change

[Correction content]

When the weight average molecular weight of the raw material resin is less than 12 × 10 ⁴ , it is generally difficult to reduce the amount of the polymer having a molecular weight of 1 × 10 ³ or less to less than 5% by weight of the resin. Even if a resin is obtained by devising a polymerization method, it will be a resin with a very narrow molecular weight distribution or a resin with a molecular weight distribution deviated to the high molecular weight side. To mold this resin, raise the molding temperature or increase the shear stress. It is necessary, and the moldability is extremely deteriorated.

[Procedure Amendment 7]

[Document name to be amended] Statement

[Correction target item name] 0034

[Correction method] Change

[Correction content]

As described above, when the polymer having a molecular weight of 1 × 10 ³ or less is 5% by weight or more of the container, impure fine particles are leached into the chemical and the cleanliness becomes 500 pieces / ml or more. Cannot be used. Examples of the molding method include blow molding, inflation molding , extrusion molding and the like.

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Claims (5)

[Claims] 1. A high-purity chemical product comprising a resin composition in which at least a light-shielding composition and a barrier composition are added to a polyethylene or ethylene / α-olefin copolymer resin having a density of 0.940 to 0.970 g / cm ³ . A container having a weight average molecular weight of 12 to 26 × 10 ⁴ and a molecular weight of 1 × as measured by gel permeation chromatography.
The polymer of 10 ³ or less is less than 5% by weight of the resin, the α-olefin is at least one selected from propylene, butene-1, 4-methyl-pentene-1, hexene-1, and octene-1. A container for high-purity chemicals characterized by: 2. The light-shielding composition contains at least a light-shielding pigment, and the light-shielding pigment is an inorganic pigment of titanium oxide, carbon black, and red iron oxide, a phthalocyanine-based pigment,
The container for high-purity chemicals according to claim 1, wherein the container is made of at least one selected from quinacridone-based and azo-based organic pigments, and is 0.01% to 5% by weight of the resin composition. 3. The light-shielding composition contains a pigment dispersant, and the pigment dispersant is composed of at least one olefin polymer selected from polyethylene and polypropylene having a number average molecular weight of 2 × 10 ³ or more. Of the resin composition
The container for high-purity chemicals according to claim 2, which is less than 5% by weight. 4. The barrier composition is a polyamide,
A mixture of at least one selected from polyvinyl alcohol and poly (ethylene-co-vinyl alcohol) and a polyolefin having a carboxyl group, which is 4% by weight to 25% by weight of the resin composition. Item 1. A container for high-purity chemicals according to Item 1. 5. The content of each of the neutralizing agent, antioxidant and light stabilizer in the resin composition, which is determined by liquid chromatography, is 0.1% by weight or less of the resin composition. The container for high-purity chemicals according to claim 1.