Method for manufacturing high-cleanliness clean container and high-cleanliness clean container manufactured thereby

Abstract

Disclosed are a method for manufacturing a high-cleanliness clean container and a high-cleanliness clean container manufactured thereby. The disclosed method for manufacturing a high-cleanliness clean container comprises the steps of: a) forming a container manufacturing chamber into a cleanroom with cleanliness class 1000, in which the number of dust particles having a size of 0.5 μm or more is 1000 or less per cubic foot; b) producing clean air for blow molding, the clean air having 0 dust particles with a size of 0.3 μm or more; and (c) manufacturing a clean container by a blow molding method using the clean air, within the container manufacturing chamber formed into a cleanroom with cleanness class 1000.

Description

Method for manufacturing a high-purity clean container and a high-purity clean container manufactured thereby

[0001] The present invention relates to a method for manufacturing a clean container for cleaning an IBC container for transporting and storing clean chemicals or hazardous materials used in semiconductor manufacturing processes, LCDs, etc., and to a clean container manufactured thereby, and more particularly, to a method for manufacturing a high-purity clean container that minimizes fine particles inside the container and minimizes the generation of leached substances due to chemical products, and to a high-purity clean container manufactured thereby.

[0002]

[0003] Generally, IBC (Intermediate Bulk Container) is a container that is standardized and manufactured to be easy to move and ship, and is usually used to transport and transport liquid hazardous materials.

[0004] These IBC containers are used to transport various chemicals used in the manufacture of semiconductors, LCDs, etc., such as semiconductor reagents such as ammonia water and LCD manufacturing reagents. These semiconductor chemicals are very sensitive to the cleanliness of the IBC container.

[0005] In other words, if there are a lot of fine particles (fine dust) in the container used to transport hazardous materials such as chemical products, or if a lot of leached substances (metal ions) are generated from the clean container when semiconductor chemicals are placed in the container, this causes a huge problem of causing astronomical losses by causing defects in the semiconductor products.

[0006] However, as there are currently no cleaned products in IBC containers, there is an urgent need to develop manufacturing technology for clean containers that can improve the cleanliness of the containers.

[0007] <Prior art literature>

[0008] Republic of Korea Publication Patent No. 10-2012-0028951

[0009] Republic of Korea Patent Publication No. 10-2020-0031131

[0010] Republic of Korea Patent Publication No. 10-2022-0084143

[0011]

[0012] The present invention was created to solve the above-mentioned conventional problems, and the purpose of the present invention is to provide a method for manufacturing a high-purity clean container, which has a small number of particles and minimizes the generation of leached substances by chemical products, thereby preventing contamination of chemical products by particles and leached substances, thereby preventing a decrease in purity and maintaining the quality of chemical products without deterioration, and a high-purity clean container manufactured thereby.

[0013]

[0014] However, the purpose of the present invention is not limited to this, and it goes without saying that the purpose or effect that can be understood from the solution or embodiment of the problem even if not explicitly mentioned is also included.

[0015]

[0016] The method for manufacturing a high-purity clean container of the present invention for achieving the above-mentioned object is characterized by including the steps of: a) forming a container manufacturing room into a clean room of cleanliness class 1000 having 1000 or fewer dust particles of 0.5 um or more in size per cubic foot; b) forming clean air for blow molding having 0 dust particles of 0.3 um or more in size; c) forming a clean container by blow molding using the clean air in the container manufacturing room formed into the clean room of cleanliness class 1000.

[0017] In the above step c), the blow molding method can be configured to manufacture a multilayer clean container having a three-layer structure of an outer skin, a middle skin, and an inner skin by applying a multilayer blow molding method.

[0018] The above step c) may be configured to include: c1) a step in which the first raw material resin, the second raw material resin, and the third raw material resin supplied to three extruders are transferred to the die head of the extruder, and a tube-shaped parison having a three-layer structure is discharged through the die head; c2) a step in which the clean air is injected into the inside of the tube-shaped parison while the tube-shaped parison is placed in a mold, thereby causing the tube-shaped parison to inflate so as to be in close contact with the cavity of the mold, thereby manufacturing a multi-layer clean container.

[0019] The first raw material resin, the second raw material resin, and the third raw material resin are all made of HMWPE (high molecular-weight polyethylene), and the multilayer clean container formed by the first raw material resin, the second raw material resin, and the third raw material resin can be configured as a three-layer structure in which the outer skin, the middle skin, and the inner skin are all made of HMWPE material.

[0020] The third raw material resin may be manufactured using a smaller amount of catalyst than the first raw material resin and the second raw material resin, and the inner skin may be configured to have less residual catalyst than the outer skin and the middle skin.

[0021] The residual catalyst amount of the inner skin may be configured to be 20 to 30% less than the residual catalyst amount of the outer skin and middle skin.

[0022]

[0023] According to the above, the present invention manufactures a high-purity clean container having a three-layer structure consisting of an outer shell, a middle shell, and an inner shell by blow molding HMWPE raw resin using clean air of high purity in a class 1000 clean room, thereby having very few particles inside the container and minimizing the generation of leached substances by chemical products, thereby preventing deterioration of the chemical products being transported and preventing a decrease in purity.

[0024] In particular, the present invention manufactures the outer skin, the middle skin, and the inner skin all from HMWPE raw material resin, and by applying a raw material resin for the inner skin that comes into direct contact with the storage material and is manufactured using less catalyst than the outer skin and the middle skin, the inner skin contains significantly less residual catalyst than the outer skin and the middle skin, thereby lowering the manufacturing cost and reducing the generation of leached substances.

[0025] In addition, the various advantageous advantages and effects of the present invention are not limited to the above-described contents, and will be more easily understood in the process of explaining specific embodiments of the present invention.

[0026]

[0027] Figure 1 is a flow chart showing a method for manufacturing a high-purity clean container according to one embodiment of the present invention.

[0028] FIG. 2 and FIG. 3 are drawings for explaining a method for manufacturing a high-purity clean container according to one embodiment of the present invention.

[0029] FIG. 4 is a drawing showing a three-layer structure of a clean container manufactured by a method for manufacturing a high-purity clean container according to an embodiment of the present invention.

[0030] FIGS. 5 to 9 are particle test data and result graphs for clean containers manufactured by a method for manufacturing a high-purity clean container according to an embodiment of the present invention, wherein FIGS. 5 and 6 are results for an embodiment (clean container of the present invention), FIGS. 7 and 8 are results for comparative example 1, and FIGS. 9 and 10 are results for comparative example 2.

[0031] FIG. 11 and FIG. 12 are test data of leached substances for a clean container manufactured by a method for manufacturing a high-purity clean container according to an embodiment of the present invention. FIG. 11 shows the results for an embodiment (a clean container of the present invention), and FIG. 12 shows the results for a comparative example.

[0032]

[0033] The above-described purposes, other purposes, features, and advantages of the present invention will be readily understood through the following preferred embodiments, illustrated in the accompanying drawings. However, the present invention is not limited to the embodiments described herein and may be embodied in other forms. Rather, the embodiments introduced herein are provided to ensure that the disclosure is thorough and complete, and to ensure that the spirit of the present invention is fully conveyed to those skilled in the art.

[0034] In this specification, when a component is referred to as being on another component, it means that it can be formed directly on the other component, or a third component may be interposed between them. Furthermore, in the drawings, the thicknesses of the components are exaggerated for the purpose of effectively explaining the technical contents.

[0035] Embodiments described herein will be described with reference to cross-sectional and / or plan views, which are ideal illustrative illustrations of the present invention. In the drawings, the thicknesses of films and regions are exaggerated for effective explanation of the technical contents. Therefore, the shapes of the illustrative drawings may be modified due to manufacturing techniques and / or tolerances. Therefore, embodiments of the present invention are not limited to the specific shapes illustrated, but also include variations in shapes created according to the manufacturing process. For example, an etched region depicted at a right angle may be rounded or have a shape with a predetermined curvature. Therefore, the regions illustrated in the drawings have properties, and the shapes of the regions illustrated in the drawings are intended to illustrate specific shapes of regions of the device and are not intended to limit the scope of the invention. Although terms such as "first" and "second" are used to describe various components in various embodiments of the present invention, these components should not be limited by such terms. These terms are used merely to distinguish one component from another. The embodiments described and illustrated herein also include complementary embodiments thereof.

[0036] The terminology used herein is for the purpose of describing embodiments and is not intended to limit the present invention. In this specification, the singular also includes the plural unless specifically stated otherwise. As used herein, the words "comprises" and / or "comprising" do not exclude the presence or addition of one or more other components.

[0037] In describing the specific embodiments below, various specific details have been included to further explain the invention and facilitate understanding. However, readers with sufficient knowledge of the field to understand the present invention will recognize that the present invention can be used without these specific details. In some cases, it is noted in advance that commonly known but largely unrelated aspects of the invention have been omitted to avoid unnecessary confusion in the description of the invention.

[0038] Referring to FIGS. 1 to 4, a method for manufacturing a high-purity clean container according to an embodiment of the present invention and a high-purity clean container manufactured thereby are described.

[0039] The method for manufacturing a high-purity clean container of the present invention is manufactured by blow molding (also called 'hollow molding') and is manufactured by a clean container manufacturing facility.

[0040] The high-purity clean container manufacturing facility of the present invention includes a container manufacturing room (10), an external device (20) for making the container manufacturing room (10) into a clean room, a blow molding device (30, 40) installed in the container manufacturing room (10) for blow molding a clean container, and a clean air manufacturing device (50) for manufacturing clean air for blow molding.

[0041] The external air conditioner (20) is a device that supplies air from the outside to the inside of the container manufacturing room (10) to create a clean room of a predetermined class in the container manufacturing room (10). This external air conditioner (20) may be configured to include an air circulation path (21) that introduces air discharged from the container manufacturing room (10) back into the container manufacturing room (10), a fan motor (22) that is installed on the air circulation path (21) to form an air movement flow, and a current filter (23) and an afterflow filter (24) that are installed before and after the fan motor (22) to purify the air. However, the external air conditioner (20) is not limited to the configuration described above, and the external air conditioner (20) may be configured as various known external air conditioners for creating a clean room in a form that supplies purified air to the container manufacturing room (10) to create a high-purity clean room in the container manufacturing room (10).

[0042] In the present invention, the container manufacturing room (10) is configured to be a class 1000 clean room through an external device (20).

[0043] A clean room is a space where the indoor air is maintained at an appropriate level by limiting the number of particulate matter contained in the air.

[0044] The class indicating the cleanliness is an indicator of the cleanliness of a clean room, and is classified from class 1 to class 100,000 according to the number of particles larger than 0.5 um per cubic foot.

[0045] The class specifications are as shown in Table 1 below.

[0046] Cleanliness grade Number of particles with a particle size of 0.5 / um (per 1f3) Class 11 Class 1010 Class 100100 Class 10001000 Class 1000010000 Class 100000100000

[0047] In the present invention, the container manufacturing room (10) is configured to be a class 1000 clean room in which the number of particles (particle count) of 0.5 um or more per cubic foot is 1000 or less through an external device (20). The blow molding equipment (30, 40) is configured to perform blow molding under the class 1000 clean room configuration.

[0048] The blow molding device (30, 40) may be a conventional blow molding device, and in particular, in the present invention, it is a multilayer blow molding device for blow molding a clean container having a three-layer structure.

[0049] The blow molding device (30, 40) includes an extrusion device (30) and a blow mold part (40).

[0050] The extrusion device (30) includes a screw extrusion unit (32) that receives three raw material resins, heats them, and transports them, and a die head (34) that forms and discharges the three raw material resins extruded and transported by the screw extrusion unit (32) into a three-layer tube-shaped parison (preformed material, see p of FIG. 3).

[0051] The blow mold section (40) is configured to include two divided separate molds (42) and an injection nozzle (44) that injects clean air into a tube-shaped parison (p) fitted into the separate molds (42).

[0052] However, the blow molding device (30, 40) is not limited to the configuration or structure described above, and can of course be formed as a conventional multilayer blow molding device.

[0053] The present invention is characterized in that the blow molding device (30, 40) is configured in a container manufacturing room (10), and the cleanliness of the clean container can be improved by performing blow molding in a state where the container manufacturing room (10) is configured as a class 1000 clean room.

[0054] In addition, the present invention has an additional feature in that a clean container is manufactured by multilayer blow molding in a state where the container manufacturing room (10) is configured as a class 1000 clean room, and when performing multilayer blow molding, highly purified clean air is used for blow molding.

[0055] The clean air production device (50) is a device for producing high-purity clean air for blow molding, and as illustrated in the drawing, may include a fan motor (51) and a plurality of nano filters (52) that remove particles to a high degree as the air transported by the fan motor (51) passes through them. However, the present invention is not limited thereto, and it goes without saying that any conventional device can be applied as long as it is a device capable of producing high-purity air with high-purity particles removed.

[0056] In the present invention, the clean air for blow molding used to manufacture a clean container by blow molding is configured to use high-purity air having zero fine particles (fine dust) of 0.3 um or more. Accordingly, it is preferable that the clean air manufacturing device (50) be configured to manufacture high-purity air having zero fine particles (fine dust) of 0.3 um or more.

[0057] Hereinafter, a method for manufacturing a high-purity clean container according to an embodiment of the present invention includes a clean room composition step (s10), a clean air production step (s20), and a clean container production step (s30).

[0058] The clean room composition step (s10) is configured to create a container manufacturing room (10) as a clean room of cleanliness class 1000 with no more than 1000 dust particles of 0.5 um or larger in size per cubic foot.

[0059] The clean air manufacturing step (s20) is configured to manufacture clean air for blow molding with 0 dust particles larger than 0.3 um in size.

[0060] The clean container manufacturing step (s30) is configured to manufacture a clean container by blow molding using the clean air manufactured in the above step s20) in a container manufacturing room (10) configured as a class 1000 clean room.

[0061] The clean container (v) manufactured by the manufacturing method of the present invention is manufactured from HMWPE (high molecular-weight polyethylene) material. The outer shell (v1), middle shell (v2), and inner shell (v3) of the clean container (v) are all composed of HMWPE (high molecular-weight polyethylene) material.

[0062] HMWPE (high molecular-weight polyethylene) is a type of PE (polyethylene) and is made by polymerizing a monomer called ethylene (or ethene) with the chemical formula C2H4 in the presence of a Ziegler-Natta catalyst or chromium catalyst. This HMWPE is classified as an engineering plastic due to its excellent wear resistance, impact resistance, and chemical resistance.

[0063] In the present invention, HMWPE raw material resin is supplied to each of three screw extrusion sections (32) to form a three-layered tubular parison (p) through a die head (34) and discharged, and after the two separate molds (32) are joined while being sandwiched between them, clean air for blow molding manufactured through a clean air manufacturing device (50) is supplied to an injection nozzle (44), and the clean air is injected into the three-layered tubular parison (p) through the injection nozzle (44) so ​​that the three-layered tubular parison (p) is inflated while being pressed against the cavities of the two separate molds (32), so that a three-layered clean container is manufactured by a multilayer blow molding method.

[0064] However, the clean container of the present invention may be configured such that the inner skin (v3) has less residual catalyst than the outer skin (v1) and the middle skin (v2) in consideration of reducing material costs while minimizing the amount of leached substances from the clean container when containing semiconductor chemicals, etc.

[0065] That is, the raw material resin supplied to the three screw extrusion units (32) is all composed of HMWPE, but the HMWPE raw material resin supplied to the third screw extrusion unit among the first, second, and third screw extrusion units (32) is manufactured using less catalyst than the HMWPE raw material resin supplied to the first and second screw extrusion units.

[0066] When manufacturing HMWPE raw material resin by polymerizing ethylene monomer under a catalyst, the third HMWPE raw material resin for forming the inner layer (v3) is used with a catalyst usage of 20 to 30% less by weight than the first and second HMWPE raw material resins for forming the outer layer (v1) and the middle layer (v2).

[0067] For example, when the amounts of catalyst used in manufacturing the first HMWPE raw resin forming the outer shell (v1) and the second HMWPE raw resin forming the middle shell (v2) are the same, and when the amounts of each catalyst used in manufacturing the first HMWPE raw resin forming the outer shell (v1) and the second HMWPE raw resin forming the middle shell (v2) are based on 100 parts by weight, the third HMWPE raw resin forming the inner shell (v3) is manufactured using 20 to 30 parts by weight.

[0068] The catalyst is intended to promote the polymerization reaction during the polymerization of the HWMPE polymer compound, and remains in the manufactured HMWPE polymer. When the third HMWPE raw resin is manufactured using 20 to 30% less catalyst than the first and second HMWPE raw resins, the clean container having a three-layer structure manufactured by the present invention has a residual catalyst amount in the inner skin (v3) of 20 to 30% of that in the outer skin (v1) or the middle skin (v2). For example, when the residual catalyst amounts in the outer skin (v1) and the middle skin (v2) of the clean container (v) manufactured by the manufacturing method of the present invention are regarded as 1, the residual catalyst amount in the inner skin (v3) is 0.2 to 0.3.

[0069] The inner skin (v3) is a part that can generate leaches by directly contacting the chemical products contained in the clean container. By manufacturing the residual catalyst amount of the inner skin (v3) to be 20-30% of that of the outer skin (v1) and middle skin (v2), the leaches generated by the residual catalyst reacting with the chemical products can be significantly reduced. At the same time, the middle skin (v2) and outer skin (v1), which do not directly contact the chemical products and thus do not generate leaches, can be manufactured with materials that have a higher residual catalyst content and a lower manufacturing cost than the inner skin (v3), thereby reducing the overall material cost.

[0070]

[0071] - 1. Container particle test

[0072] FIGS. 5 to 9 are particle test data and result graphs for clean containers manufactured by a method for manufacturing a high-purity clean container according to an embodiment of the present invention, wherein FIGS. 5 and 6 are results for an embodiment (clean container of the present invention), FIGS. 7 and 8 are results for comparative example 1, and FIGS. 9 and 10 are results for comparative example 2.

[0073] <Example>

[0074] Condition A1 - Manufactured in a Class 1000 cleanroom in the container manufacturing facility.

[0075] Condition A2 - Manufactured using clean air with no dust particles larger than 0.3um in size during blow molding.

[0076] Condition A3 - The first, second, and third raw material resins for forming the outer skin, middle skin, and inner skin are each made of HMWPE resin, but the third raw material resin for the inner skin is manufactured using only 20-30% of the catalyst for polymerization reaction applied during the manufacturing of the HMWPE raw material resin compared to the first and second raw material resins for the outer skin and middle skin.

[0077] For the examples (clean container of the present invention) having conditions A1, A2, and A3, particles were measured using a liquid particle counter (KS-40AF).

[0078] Figures 5 and 6 are test data and result graphs of particle particles for an embodiment of the present invention.

[0079]

[0080] <Comparative Example 1>

[0081] Condition B1 - Manufactured in a Class 1000 clean room in the container manufacturing room.

[0082] Condition B2 - Manufactured using clean air with no dust particles larger than 0.3um in size during blow molding.

[0083] Condition B3 - For forming the outer skin, middle skin, and inner skin, each of the first, second, and third raw material resins uses HMWPE resin, and the first, second, and third raw material resins are all applied with 100% of the amount of catalyst used for polymerization reaction in the manufacture of general HMWPE raw material resin.

[0084] For comparative example 1 having the above conditions B1, B2, and B3, particles were measured using a liquid particle counter (KS-40AF).

[0085] Figures 7 and 8 are test data and result graphs of particle particles for an embodiment of the present invention.

[0086]

[0087] <Comparative Example 2>

[0088] Condition C1 - Container manufacturing is not carried out in a cleanroom but in a general manufacturing facility.

[0089] Condition C2 - Blow molding is performed using normal air rather than clean air.

[0090] Condition C3 - Each of the first, second, and third raw material resins for forming the outer skin, middle skin, and inner skin uses HMWPE resin, and the first, second, and third raw material resins are all applied with 100% of the amount of catalyst used for polymerization reaction in the manufacture of general HMWPE raw material resin.

[0091] For comparative example 2 having the above conditions C1, C2, and C3, particles were measured using a liquid particle counter (KS-40AF).

[0092] Figures 9 and 10 are test data and result graphs of particle particles for an embodiment of the present invention.

[0093] As a result of the test, as shown in FIGS. 5 to 10, the amount of particles in the examples is smaller than in comparative examples 1 and 2, and in particular, in the examples, there are no particles with a particle size of 0.3 μm or more, and in addition, the amount of particles measured over time tends to remain constant rather than increase, but in comparative examples 1 and 2, a lot of elution occurs from the container for the test liquid added to the sample for liquid particle counter measurement over time, and the amount of particles measured tends to increase.

[0094]

[0095] - 2. Test of container elution

[0096] FIG. 11 and FIG. 12 are test data of leached substances for a clean container manufactured by a method for manufacturing a high-purity clean container according to an embodiment of the present invention. FIG. 11 shows the results for an embodiment (a clean container of the present invention), and FIG. 12 shows the results for a comparative example.

[0097] The examples and comparative examples are all manufactured under the same conditions of using clean air with no dust particles larger than 0.3 μm in size during blow molding in a class 1000 clean room in a container manufacturing room, and the only difference is in the materials used to manufacture the containers. In the examples, the first, second, and third raw material resins for forming the outer skin, middle skin, and inner skin are HMWPE resins, but the third raw material resin for the inner skin is manufactured using only 20 to 30% of the catalyst for the polymerization reaction when manufacturing the HMWPE raw material resin compared to the first and second raw material resins for the outer skin and middle skin. In the comparative examples, the first, second, and third raw material resins for forming the outer skin, middle skin, and inner skin are HMWPE resins, and the first, second, and third raw material resins are all manufactured using 100% of the catalyst amount used for the polymerization reaction when manufacturing a general HMWPE raw material resin.

[0098] In each of the examples and comparative examples, the components eluted from the container as a storage material were analyzed while phosphoric acid was placed as a storage material.

[0099] As seen in Figures 11 and 12, in the comparative example, detection of components in the ppm unit was performed, and in the embodiment, detection of trace components in the ppb unit, which is 1 / 1000 lower than the ppm unit, was confirmed.

[0100]

[0101] While the present invention has been illustrated and described with reference to preferred embodiments intended to illustrate the principles of the invention, it is not intended to be limited to the exact configuration and operation described herein. Rather, those skilled in the art will readily appreciate that numerous modifications and variations are possible without departing from the spirit and scope of the appended claims. Accordingly, all such appropriate modifications and variations, as well as their equivalents, should be considered within the scope of the present invention.

[0102]

[0103] As described above, the present invention can be widely used in the industrial field of hazardous material containers such as chemical products, reagents, etc., such as IBC containers.

[0104]

[0105] 10...Courage Manufacturing Lab

[0106] 20...Outside assistant

[0107] 21...Air circulation path

[0108] 22...fan motor

[0109] 23...current filter

[0110] 24...backflow filter

[0111] 30...extrusion device

[0112] 32...screw extrusion section

[0113] 34...Die Head

[0114] 40...Mold section

[0115] 42...Separation mold

[0116] 44...injection nozzle

[0117] 50...Clean air production device

[0118] 51...fan motor

[0119] 52...Nanofilter

[0120] v...clean container

[0121] v1...outer shell

[0122] v2...Mesothelium

[0123] v3...endothelium

Claims

1. a) A step of creating a container manufacturing room as a clean room of cleanliness class 1000 with no more than 1000 dust particles of 0.5um or larger in size per cubic foot; b) A step of producing clean air for blow molding having 0 dust particles with a size of 0.3 um or more; c) A method for manufacturing a high-purity clean container, characterized by including a step of manufacturing a clean container by a blow molding method using the clean air in a container manufacturing room constructed as a clean room of the above cleanliness class 1000.

2. In paragraph 1, A method for manufacturing a high-purity clean container, characterized in that in the step c), the blow molding method is configured to manufacture a multilayer clean container having a three-layer structure of an outer skin, a middle skin, and an inner skin by applying a multilayer blow molding method.

3. In paragraph 2, Step c) above, c1) A step in which the first raw material resin, the second raw material resin, and the third raw material resin supplied to three extruders are transferred to the die head of the extruder, and a tube-shaped parison having a three-layer structure is discharged through the die head; c2) A method for manufacturing a high-purity clean container, characterized by including a step of manufacturing a multi-layer clean container by injecting clean air into the inside of the tube-shaped parison while the tube-shaped parison is placed in the mold, thereby causing the tube-shaped parison to inflate so as to be in close contact with the cavity of the mold.

4. In paragraph 3, A method for manufacturing a high-purity clean container, characterized in that the first raw material resin, the second raw material resin, and the third raw material resin are all made of HMWPE (high molecular-weight polyethylene), and the multilayer clean container formed by the first raw material resin, the second raw material resin, and the third raw material resin is configured as a three-layer structure in which the outer skin, the middle skin, and the inner skin are all made of HMWPE material.

5. In paragraph 4, A method for manufacturing a high-purity clean container, characterized in that the third raw material resin is manufactured using a smaller amount of catalyst than the first raw material resin and the second raw material resin, and the inner skin is configured to have less residual catalyst than the outer skin and the middle skin.

6. In paragraph 5, A method for manufacturing a high-purity clean container, characterized in that the residual catalyst amount of the inner skin is 20 to 30% less than the residual catalyst amount of the outer skin and middle skin.

7. A high-purity clean container manufactured by the high-purity clean container manufacturing method described in any one of paragraphs 1 to 6.

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