KR102240735B1 - Sheet comprising inline-laminated antistatic PMMA film and manufacturing method thereof - Google Patents

Abstract

The present invention is a) a substrate layer of a transparent ABS resin, PMMA resin or impact resistant PMMA resin; And b) an antistatic PMMA film laminated in-line on both surfaces of the base layer.
The antistatic sheet according to the present invention replaces the conventional polymer sheet with an antistatic coating layer, and has excellent transparency and mechanical properties, and has a very low surface resistivity. Not only can it be applied as a packaging sheet such as a mask storage case, but also mass production is possible due to a simple in-line laminating process.

Description

TECHNICAL FIELD [Sheet comprising inline-laminated antistatic PMMA film and manufacturing method thereof]

The present invention relates to a sheet including an in-line laminating antistatic PMMA film and a method for manufacturing the same, and more particularly, on a substrate layer of a transparent ABS resin, PMMA resin, or impact resistant PMMA resin, antistatic antistatic formed by in-line laminating It relates to a sheet including a PMMA film and a method of manufacturing the same.

In general, materials used in semiconductor clean rooms may cause problems such as equipment malfunction and surface contamination due to electrostatic discharge or manpower phenomenon. In other words, materials used in many manufacturing processes in the semiconductor, flat panel display, disk drive, and medical device industries are non-conducting or insulating materials, and these materials carry or generate large electric charges and pollute the atmosphere during transportation. Materials used in semiconductor clean rooms should not generate static electricity because these contaminated materials can have a fatal effect in processes such as photolithography, coating, and etching.

In particular, materials such as cases for storing and transporting finished semiconductor parts require antistatic functions. As an antistatic packaging material for packaging semiconductor parts having such antistatic functions, films or sheets are charged on the surface of a plastic resin substrate, which is an insulator. It adopts a method of compressing an anti-film, hard coating or in-line coating, or a method of incorporating an antistatic agent into a plastic resin substrate.

However, in the case of compressing the antistatic film, even though the unit cost of the film itself is high, since it is produced by compressing in multiple layers, there is a disadvantage that the unit price of the sheet itself increases due to inferior transparency and adhesion and a high defect rate in the manufacturing process. In this case, as an offline process is additionally performed after sheet production, there may be a problem in that the unit price is increased and the entire process is delayed, and the antistatic function may be significantly deteriorated over time. In addition, even when the in-line coating process is employed, there is a known disadvantage in that the antistatic function may rapidly deteriorate after washing with water.

On the other hand, as the mixing method, an antistatic sheet formed into a sheet form by adding an antistatic agent such as carbon black to an insulating material having excellent electrical insulating properties such as polyethylene, polypropylene, polyvinyl chloride, polystyrene, polyethylene terephthalate resin, etc. is known. If the dispersibility of the carbon black is non-uniform, there may be a problem with a large antistatic deviation depending on the portion of the sheet. In addition, polyolefin resin compositions that improve the appearance and transparency of sheets by mixing and molding a specific block copolymer as a high molecular weight antistatic agent into a resin composition have been known, but the cost of sheet production due to the use of a high molecular weight antistatic agent has been known. There is a new problem of rising.

Therefore, the present inventors use a transparent ABS (acrylonitrile-butadiene-styrene copolymer) resin, a PMMA resin, or an impact resistant PMMA resin as a base layer, and a PMMA antistatic film is laminated on both surfaces of the base layer by a simple in-line laminating process. In this regard, the present invention has been completed by focusing on the application of a sheet for packaging of electronic components, including semiconductor components, without a complicated separate coating and drying process.

Patent Document 1. Registered Patent Publication No. 10-0650152 Patent Document 2. Unexamined Patent Publication No. 10-2005-0053355 Patent Document 3. Unexamined Patent Publication No. 10-2012-0101592

Therefore, the present invention has been conceived in consideration of the above problems, and an object of the present invention is a vertically symmetric antistatic PMMA film laminated on a base layer of transparent ABS resin, PMMA resin or impact resistant PMMA resin by a simple in-line laminating process. It is intended to provide a sheet and a method of manufacturing the same, and apply it as a packaging sheet for electronic components including semiconductor components.

The present invention for achieving the object as described above is a) a substrate layer of a transparent ABS resin, PMMA resin or impact resistant PMMA resin; And b) an antistatic PMMA film laminated in-line on both surfaces of the base layer.

The antistatic PMMA film of b) is characterized by injection-molding a master batch consisting of 75 to 85% by weight of a PMMA resin and 15 to 25% by weight of an antistatic agent.

The antistatic agent is characterized in that it is an inorganic or organic compound.

The inorganic compounds are ZnO, ZnSb ₂ O ₆ , InSbO ₄ , TiO ₂ , ZrO ₂ , SnO ₂ , Sb ₂ O ₃ , Sb ₂ O ₅ , Al ₂ O ₃ , In ₂ O ₃ , SiO ₂ , MgO, BaO, MoO ₃ , BaSO ₄ , SrSO ₄ , MgSO ₄ , MgCO ₃ and CaCO _{3 It} is characterized in that at least one selected from the group consisting of.

The organic compound is characterized in that it is a nonionic, anionic, cationic or amphoteric surfactant or a conductive polymer.

The antistatic sheet is characterized in that it is for packaging electronic components.

In addition, the present invention comprises the steps of: I) supplying a transparent ABS resin, PMMA resin, or impact resistant PMMA resin to an extruder, melting and kneading, and extruding to form a base layer sheet; And II) transferring the base layer sheet to an in-line laminating device to sequentially in-line laminating an antistatic PMMA film on both surfaces of the base layer sheet.

The antistatic sheet according to the present invention replaces the conventional polymer sheet with an antistatic coating layer, and has excellent transparency and mechanical properties, and has a very low surface resistivity. Not only can it be applied as a packaging sheet such as a mask storage case, but also mass production is possible due to a simple in-line laminating process.

1 is a cross-sectional view of an antistatic sheet according to the present invention.

Hereinafter, a sheet including an in-line laminating antistatic PMMA film according to the present invention and a manufacturing method thereof will be described in detail with reference to the accompanying drawings.

In the present invention, a) a substrate layer of a transparent ABS resin, PMMA resin or impact resistant PMMA resin; And b) an antistatic PMMA film laminated in-line on both surfaces of the base layer.

A transparent ABS resin, a PMMA resin, or an impact resistant PMMA resin may be used as the material constituting the base layer, and the ABS resin, PMMA resin, or impact resistant PMMA resin has good mechanical properties and is therefore suitable as a base layer in a multilayered sheet. In particular, it is preferable to use an ABS resin or a PMMA resin in a transparent state because the contained parts can be visually confirmed when applied to packaging sheets such as electronic parts including semiconductor parts.

As shown in the cross-sectional view of the antistatic sheet shown in FIG. 1, a transparent ABS (acrylonitrile-butadiene-styrene) resin is used as the polymer material constituting the base layer 10 of the antistatic sheet 100 according to the present invention. As can be seen, in general, ABS resin is a copolymer having excellent chemical resistance of acrylonitrile, impact resistance of butadiene, and excellent processability of styrene, and is widely used as a material for furniture or bathtubs.

This ABS resin has a structure of a copolymer in which an acrylonitrile monomer and a styrene monomer are grafted onto a butadiene rubber polymer. Although the proportion can be appropriately adjusted, in the present invention, the ABS resin is preferably used as an ABS resin containing 15 to 35% by weight of acrylonitrile monomer, 5 to 30% by weight of butadiene rubber, and 40 to 60% by weight of styrene monomer.

If the content of the acrylonitrile monomer constituting the ABS resin is less than 15% by weight, chemical resistance may be reduced, and if it exceeds 35% by weight, thermal discoloration may occur during the molding process. In addition, if the content of the butadiene rubber is less than 5% by weight, impact strength may decrease, and if it exceeds 30% by weight, thermal stability may decrease. In addition, when the content of the styrene monomer is less than 40% by weight, processability is deteriorated, and when it exceeds 60% by weight, chemical resistance is deteriorated.

In addition, it is preferable that the butadiene rubber has an average particle diameter of 0.05 to 0.5 μm. If the average particle diameter of the butadiene rubber is less than 0.05 μm, the impact resistance may be lowered, and if it exceeds 0.5 μm, the acrylonitrile monomer and styrene The degree to which the monomer is grafted is lowered, so that the molecular weight of the copolymer may decrease.

Meanwhile, as a polymer material constituting the base layer 10 of the antistatic sheet 100 according to the present invention, a PMMA resin may be used. This refers to the unmodified state. PMMA resin is widely used as a material for plastic products due to its excellent transparency, gloss, and molding processability. In particular, it adapts well to ultraviolet rays and does not discolor due to its excellent transparency, gloss and molding processability. And is suitable as a material used for the base layer 10 of the antistatic sheet 100 according to the present invention.

In addition, impact-resistant PMMA resin may be used as a polymer material constituting the base layer 10 of the antistatic sheet 100 according to the present invention. As the impact-resistant PMMA resin, a rubber-like resin component is contained while having a PMMA block in the resin. As a result, it can be used in the form of a copolymer or a blend. For the copolymer type, a copolymer resin in which an acrylic rubber block such as polyacrylate is mixed with a PMMA block as a copolymer resin of an MMA (methyl methacrylate) monomer and an ethyl acrylate or butyl acrylate monomer can be preferably used. have. On the other hand, in the blended form, PMMA resin and MBS (methyl methacrylate-butadiene-styrene) resin, MABS (methyl methacrylate-acrylonitrile-butadiene-styrene) resin, SBC (thermoplastic styrene block copolymer) resin or A blend resin of ABS (acrylonitrile-butadiene-styrene) resin can be preferably used, and in particular, it is more preferable to use PMMA-MBS resin, which is a blend of PMMA resin and MBS resin.

In addition, the antistatic sheet 100 according to the present invention includes antistatic PMMA films 20 and 30 laminated in-line on both surfaces of the base layer 10 described above, and the antistatic PMMA film is a PMMA resin 75 It is preferable to use one prepared by injection molding a master batch consisting of ~85% by weight and 15-25% by weight of an antistatic agent.

When the content of the antistatic agent constituting the antistatic PMMA film exceeds 25% by weight, it is difficult to obtain a uniform film after injection molding due to poor dispersibility with the PMMA resin, which is a raw material resin in the process of obtaining a master batch, and excessive charging. There is a concern that the transparency may decrease depending on the use of the inhibitor, and if the content of the antistatic agent is less than 15% by weight, the antistatic properties may be deteriorated.

At this time, as the antistatic agent, an inorganic or organic compound can be used, and the inorganic compound is a crystalline metal oxide or a fine powder of ZnO, ZnSb ₂ O ₆ , InSbO ₄ , TiO ₂ , ZrO ₂ , SnO ₂ , Sb ₂ At least one selected from the group consisting of _{O 3} , Sb ₂ O ₅ , Al ₂ O ₃ , In ₂ O ₃ , SiO ₂ , MgO, BaO, MoO ₃ , BaSO ₄ , SrSO ₄ , MgSO ₄ , MgCO ₃ and CaCO ₃ Can be.

In addition, the organic compound may be a nonionic, anionic, cationic or amphoteric surfactant, such as an ethoxylated alkylamine, a glycerin fatty acid ester, a sorbitan fatty acid ester, or an alkyl ethanol amide. Active agents, or anionic surfactants such as alkyl sulfonates, alkyl phosphates or alkylbenzene sulfonates, cationic surfactants such as tetraalkyl ammonium salts or trialkylbenzyl ammonium salts, or alkyl betaine, alkylalanine or imidazoline, etc. An amphoteric surfactant may be used, and in particular, it may be preferably selected in consideration of transparency.

In addition, as the organic compound, a conductive polymer such as polyaniline, polypyrrole, polythiophene or PEDOT [poly(3,4-ethylenedioxythiophene)] may be used.

In addition, the present invention comprises the steps of: I) supplying a transparent ABS resin, PMMA resin, or impact resistant PMMA resin to an extruder, melting and kneading, and extruding to form a base layer sheet; And II) transferring the base layer sheet to an in-line laminating device to sequentially in-line laminating an antistatic PMMA film on both surfaces of the base layer sheet.

First, as in the present invention, all known molding methods such as injection molding, extrusion molding, and compression molding can be used to manufacture a flat sheet using a thermoplastic resin such as transparent ABS resin, PMMA resin, or impact-resistant PMMA resin as a raw material. However, in the step I), a known extrusion molding method is more preferably used.

On the other hand, in order to obtain the antistatic effect by the antistatic treatment of the thermoplastic resin, the antistatic agent is added to the thermoplastic resin composition before molding and then extruded or injection molded to mix the antistatic agent inside the thermoplastic resin, or the thermoplastic resin product after molding Antistatic agents may be applied to the surface of the In the former, the antistatic effect is sustained because the antistatic agent is mixed inside the thermoplastic resin product, whereas the latter is applied to the surface of the thermoplastic resin product, so the antistatic effect is weak over time due to friction or washing. There is a disadvantage in that the production cost is increased due to the complicated coating and drying process of the antistatic agent.

Therefore, in the present invention, the substrate layer sheet formed in step I) is transferred to an in-line laminating device, and an antistatic PMMA film is sequentially in-line laminated on both surfaces of the substrate layer sheet by a simple in-line laminating process to achieve a continuous anti-static effect. As can be seen, the antistatic sheet 100 obtained according to the manufacturing method of the present invention described above has a very low surface resistivity and can be applied as a packaging sheet for electronic components including semiconductor components.

Hereinafter, specific examples will be described in detail.

(Example 1)

A sheet (substrate layer) was formed by feeding 100 kg of transparent ABS resin pellets to the hopper portion of the extruder, melting and kneading, and extruding. Meanwhile, a master batch consisting of 80% by weight of a PMMA resin and 20% by weight of an antistatic agent was injection-molded to obtain an antistatic PMMA film. Subsequently, the formed sheet is transferred to an in-line laminating device, and an antistatic PMMA film is sequentially inline laminated on both surfaces of the sheet to prepare an antistatic sheet (antistatic PMMA film/transparent ABS base layer/antistatic PMMA film). I did.

(Example 2)

An antistatic sheet (antistatic PMMA film/PMMA substrate layer/antistatic PMMA film) was prepared in the same manner as in Example 1, except that PMMA resin pellets were used to form a sheet (substrate layer).

(Example 3)

An antistatic sheet (antistatic PMMA film/impact PMMA substrate layer/antistatic PMMA film) was prepared in the same manner as in Example 1, except that impact-resistant PMMA resin pellets were used to form a sheet (substrate layer).

(Comparative Example 1)

An antistatic sheet (antistatic PMMA film/transparent ABS substrate layer/) in the same manner as in Example 1, except that a master batch consisting of 70% by weight of PMMA resin and 30% by weight of an antistatic agent was injection-molded to obtain an antistatic PMMA film. Antistatic PMMA film) was prepared.

(Comparative Example 2)

An antistatic sheet (antistatic PMMA film/transparent ABS substrate layer/) in the same manner as in Example 1, except that a master batch consisting of 90% by weight of PMMA resin and 10% by weight of an antistatic agent was injection-molded to obtain an antistatic PMMA film. Antistatic PMMA film) was prepared.

(Test Example)

The total light transmittance (Tt) and haze (Hz) of the antistatic sheets prepared from Examples 1 to 3 and Comparative Examples 1 and 2 were measured using a haze meter according to the ASTM D1003 method, and the surface resistivity was JIS K6911 method. According to the UPMCP-HT450, the surface specific resistance value (right after sheet manufacturing and after 1 year) at an applied voltage of 500V was measured.

Table 1 below shows the total light transmittance (Tt), haze (Hz), and surface specific resistance values measured from the test examples.

Sample Tt(%) Hz(%) Surface specific resistance (Ω/cm) Immediately after sheet manufacturing 1 year later Example 1 85.0 10.0 1.1 x 10 ⁷ 1.2 x 10 ⁷ Example 2 87.1 11.2 1.0 x 10 ⁷ 1.1 x 10 ⁷ Example 3 84.5 12.1 1.1 x 10 ⁷ 1.2 x 10 ⁷ Comparative Example 1 80.2 14.1 1.2 x 10 ⁷ 1.5 x 10 ⁷ Comparative Example 2 84.5 11.5 1.3 x 10 ⁸ 1.5 x 10 ⁸

As can be seen from [Table 1], the antistatic sheets of Examples 1 to 3 manufactured according to the present invention have excellent transparency and have a surface resistivity value of 10 ⁷ order, which is seen in conventional antistatic sheets. It ^{can be confirmed that the antistatic performance is significantly lower than the surface specific resistance value of 10 9} to 10 ¹⁰ order (even in the case of Comparative Examples 1 and 2 different from Example 1 only in the content of the antistatic agent, in-line laminated antistatic PMMA Since the film is formed, the antistatic performance is superior to that of the conventional antistatic sheet).

In addition, there is almost no change in the specific surface resistivity after 1 year, so the antistatic effect is maintained even after a long period of time, so it can be used stably for a long period of time, and the unique surface required for packaging sheets such as ordinary semiconductor parts and electronic parts. It was found that the resistance value remains in a very low range.

Therefore, the antistatic sheet according to the present invention replaces the conventional polymer sheet with an antistatic coating layer, and has excellent transparency and mechanical properties, and has a very low surface resistivity. Not only can it be applied as a packaging sheet such as a photomask storage case, but also mass production is possible due to a simple in-line laminating process.

10. Base layer
20(30). In-line laminated antistatic PMMA film
100. Antistatic sheet

Claims (7)

a) a base layer of transparent ABS resin, PMMA resin, or impact resistant PMMA resin; And
b) an antistatic PMMA film comprising 75 to 85% by weight of a PMMA resin and 15 to 25% by weight of an antistatic agent laminated in-line on both surfaces of the base layer; delete The antistatic sheet according to claim 1, wherein the antistatic agent is an inorganic or organic compound. The method of claim 3, wherein the inorganic compound is ZnO, ZnSb ₂ O ₆ , InSbO ₄ , TiO ₂ , ZrO ₂ , SnO ₂ , Sb ₂ O ₃ , Sb ₂ O ₅ , Al ₂ O ₃ , In ₂ O ₃ , SiO ₂ , MgO, BaO, MoO ₃ , BaSO ₄ , SrSO ₄ , MgSO ₄ , MgCO ₃ and CaCO ₃ Antistatic sheet, characterized in that at least one selected from the group consisting of. The antistatic sheet according to claim 3, wherein the organic compound is a nonionic, anionic, cationic or amphoteric surfactant or a conductive polymer. 6. The antistatic sheet according to any one of claims 1 and 3 to 5, wherein the antistatic sheet is for packaging electronic components. I) supplying a transparent ABS resin, PMMA resin, or impact resistant PMMA resin to an extruder, melting and kneading, and extruding to form a base layer sheet; And
II) transferring the base layer sheet to an in-line laminating device and sequentially in-line laminating an antistatic PMMA film comprising 75 to 85% by weight of a PMMA resin and 15 to 25% by weight of an antistatic agent on both surfaces of the base layer sheet; Manufacturing method of an antistatic sheet comprising a.

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