JP2002292804A - Conductive sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a conductive sheet excellent in mechanical characteristics such as impact resistance or the like. SOLUTION: The conductive sheet is prepared by laminating a skin layer, which is formed from a conductive resin composition constituted of thermoplastic resins (A1 ) and (A2 ) (A) different in solubility and a conductive agent (B) and characterized in that the difference [δ (A2 )-δ (A1 )] between the solubility parameters of the components (A1 ) and (A2 ) is 1.5-10 (MPa)<1/2> and the Du Pont impact strength of the sheet with a thickness of 0.7 mm is not less than 0.5 N.m, on at least one surface of a base material sheet formed from a thermoplastic resin. The component (A1 ) is polyethylene and the component (A2 ) may be a polypropylene resin. The thermoplastic resin constituting the base material sheet may be a polyolefinic resin. The thickness ratio of the base material sheet and the skin layer is about base material sheet/skin layer=30/1-1/1 and the thickness of the skin layer is about 5-500 μm.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a conductive sheet suitable for fields such as a packaging material for semiconductors and electronic parts, and a molded article formed using the sheet.

[0002]

2. Description of the Related Art In general, sheets and molded articles formed of a thermoplastic resin have a high surface specific resistance value and are very easily charged, so that packaging materials for semiconductors and electronic parts (for example, these electronic materials are transported). Embossed tape, tray,
When used as a container or sheet for a magazine or the like, electronic materials may be damaged or destroyed by static electricity. Therefore, these packaging materials need to impart surface conductivity at least to the antistatic level. As a method of imparting conductivity to these materials, a method of kneading conductive carbon black into a thermoplastic resin is known.

Japanese Patent Application Laid-Open No. 50-32240 discloses a resin composition containing a mixture of a polyolefin and a polymer having poor compatibility with the polyolefin (polyamide, polyester, polystyrene, poly (meth) acrylate), and carbon black. Are disclosed. In this resin composition, the resin phase composed of polyolefin and the incompatible resin phase form a network structure, and carbon black is selectively dispersed in the polyolefin resin phase, so that the amount of carbon black used is small. Even in this case, the conductive path is formed efficiently. JP-A-55-152736 discloses a conductive resin composition comprising a crystalline propylene polymer, a high-density ethylene polymer, and carbon black. In this resin composition as well, the dispersion domain of polypropylene and the dispersion domain of high-density polyethylene each substantially form a continuous circuit, and carbon black is substantially included in the dispersion domain of high-density polyethylene. However, in these resin compositions, the moldability and mechanical properties of the thermoplastic resin are reduced by the addition of carbon black.

JP-A-58-24449 discloses a composite plastic sheet in which a polyolefin resin composition film containing 5 to 50 parts by weight of carbon black is laminated on one or both sides of a polyolefin sheet. JP-A-62-156949 discloses a heat-resistant composite polypropylene sheet in which a polypropylene resin composition film containing 5 to 50 parts by weight of carbon black is laminated on one or both sides of a sheet composed of a polypropylene resin and a filler. It has been disclosed.

[0005] However, these laminated sheets require a large amount of carbon black to be incorporated in order to exhibit sufficient conductivity, so that carbon black falls off from the sheet surface. In addition, the incorporation of a large amount of carbon black reduces the formability and mechanical properties of the sheet and the appearance of the sheet surface.

[0006]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a conductive sheet and a molded article having excellent mechanical properties such as impact resistance.

Another object of the present invention is to provide a conductive sheet and a molded article having excellent surface appearance.

[0008] It is still another object of the present invention to provide a conductive sheet and a molded product in which the conductive agent is less likely to fall off.

[0009]

Means for Solving the Problems As a result of intensive studies, the present inventors have found that at least one surface of a base sheet is made of two types of thermoplastic resins having a specific relationship in solubility parameter, and a conductive agent. It has been found that by laminating with the skin layer composed of the above, a conductive sheet and a molded product having excellent mechanical properties such as impact resistance can be obtained, and the present invention has been completed.

That is, in the conductive sheet of the present invention, a skin layer composed of a thermoplastic resin (A) and a conductive agent (B) is provided on at least one surface of a base sheet formed of a thermoplastic resin. In the laminated sheet, in this skin layer, the thermoplastic resin (A) is composed of thermoplastic resins (A ₁ ) and (A ₂ ) having different solubility, and the component (A ₁ ) and the component (A ₂ ) )) Difference in solubility parameter with component [δ (A ₂ ) −
δ (A ₁ )] is 1.5 to 10 (MPa) ^1/2 and the DuPont impact strength at a sheet thickness of 0.7 mm is 0.5 N ·
m or more. From the viewpoint that sufficient conductivity is exhibited by a small amount of the conductive agent, at least one of the components (A ₁ ) and (A ₂ ) forms a continuous phase in the skin layer, and (B) is contained in the continuous phase. ) Components may be included. The thermoplastic resin (A) may be composed of high-density polyethylene (A ₁ ) and polypropylene-based resin (A ₂ ). The conductive agent (B) may be conductive carbon black. The ratio (weight ratio) of the component (A ₁ ) to the component (A ₂ ) is (A ₁ ) / (A ₂ ) = 5/95 to 70/30,
It is preferably about 10/90 to 50/50, and (B)
The proportion of the component is 0.1 to 30 parts by weight, preferably 0.2 to 20 parts by weight, based on 100 parts by weight of the total of the component (A). From the viewpoint of antistatic, skin layers may be laminated on both surfaces of the base sheet. The ratio of the thickness of the base sheet to each skin layer is as follows: base sheet / skin layer = 30/1 to 1
1/1, preferably about 20/1 to 2/1. The thickness of each skin layer is 5 to 500 μm, preferably 10 to 30
It is about 0 μm. The sheet has excellent conductivity and a surface resistivity of about 1 to 10 ¹⁰ Ω / □.

The present invention also includes a molded article formed from the sheet. The present invention also includes a method of forming the sheet by a coextrusion method in which the skin layer and the base sheet are coextruded.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION The conductive sheet of the present invention has a structure in which a skin layer is laminated on at least one surface of a base sheet in order to impart sufficient conductivity without impairing the properties of the resin. is there.

[Skin Layer] The skin layer is provided for imparting conductivity to the sheet surface, and comprises (A) thermoplastic resins (A ₁ ) and (A ₂ ) having different solubilities (solubility parameters); (B) a conductive agent.

(A) Thermoplastic resin The component (A) is not particularly limited, and examples thereof include a polyolefin resin, a polystyrene resin, an acrylic resin, a vinyl resin, a polyamide resin, a polyester resin, and a polycarbonate resin. And various thermoplastic resins such as polyphenylene oxide resin, polysulfone resin, and fluorine resin, and a polyolefin resin is usually used.

Examples of the polyolefin resin include α-olefins such as ethylene, propylene, 1-butene, 3-methyl-1-pentene, 4-methyl-1-butene, 1-hexene and 1-octene (particularly α-olefins). _C2-10 olefins), such as polyolefins (polyethylene, ethylene-propylene copolymer, polypropylene, etc.), modified polyolefins [ethylene-butene-1 copolymer, ethylene Ethylene- (meth) such as-(4-methylpentene-1) copolymer, ethylene-vinyl acetate copolymer, ethylene- (meth) acrylic acid copolymer or its ionomer, ethylene-ethyl acrylate copolymer Acrylate copolymer, propylene-butene-1 copolymer, ethylene-propylene-butene 1 copolymer, and maleic polypropylene anhydride, etc.] or the like. In addition, these copolymers include a random copolymer, a block copolymer, and a graft copolymer. Among them, polyolefin resins having a C _2-10 alkylene unit (particularly, a C _2-3 alkylene unit) such as polyethylene, polypropylene, polybutene, and polyoctenylene are preferable.

The thermoplastic resins (A ₁ ) and (A ₂ ) are thermoplastic resins having different solubilities selected from the above-mentioned thermoplastic resins. Specifically, the components (A ₁ ) and (A ₁ ) ₂ ) Difference in solubility parameter with component [δ (A ₂ ) −δ (A ₁ )]
^{But, 1.5~10 (MPa) 1/2} , preferably from 1.7 to 5
(MPa) ^1/2, more preferably 1.9~3 (MPa) ^1/2
It is about. If the difference in solubility parameters is too small,
The conductive agent does not selectively dissolve in one component. If the difference between the solubility parameters is too large, the processing stability at the time of extrusion, the mechanical properties of the resin, and the like are reduced. Incidentally, the solubility parameter in the present invention, POLYMER HANDBOOK (FOURTH EDITION)
According to.

In the skin layer, (A ₁ ) and (A ₂ )
The difference in solubility parameter between the components is within the above range, and the difference in melt viscosity is increased, so that at least one of the components (A ₁ ) and (A ₂ ) (particularly, the component (A ₁ )) becomes a continuous phase. To form As the structure, only one component is a continuous phase to form a matrix, the other component is a sea-island structure dispersed in the matrix, both phases are a three-dimensional network structure, and both components are a continuous phase. A bicontinuous structure to be formed is mentioned, and a bicontinuous structure is preferable. Furthermore, since the conductive agent (B) is selectively included in one of the components forming the continuous phase, the conductive agent exists in a dense form to form a conductive path. Therefore, sufficient conductivity is provided even though the ratio of the conductive agent is small.

A preferred combination of the thermoplastic resins (A ₁ ) and (A ₂ ) is that the component (A ₁ ) is a polyethylene resin (particularly high density polyethylene) and the component (A ₂ ) is
It is a polypropylene resin.

(A ₁ ) Polyethylene resins include low-density polyethylene, medium-density polyethylene, high-density polyethylene, linear polyethylene (for example, linear low-density polyethylene), branched-chain polyethylene, low-molecular-weight polyethylene, Examples include ionomers and chlorinated polyethylene. Among these polyethylene resins, high-density polyethylene is preferable, and specifically, 0.945 g /
cm ³ or more (e.g., about 0.945~0.97g / cm ^3), preferably 0.95 g / cm ³ or more (e.g.,
0.95~0.97g / cm ³ or so), more preferably 0.96 g / cm ³ or more (e.g., 0.96 to 0.9
About 7 g / cm ³ ).

The melt flow rate (MF) of the component (A ₁ )
R) is 1 to 50 g / 10 min, preferably 3 to 40 g / 1.
0 minutes, more preferably about 5 to 30 g / 10 minutes. In addition, MFR is based on JIS K7210,
Condition 4 of Table 1 of IS K 7210 (test temperature 190
° C and a test load of 21.18 N).

(A ₂ ) As the polypropylene resin,
A propylene homopolymer or a propylene-α-olefin copolymer can be exemplified. The ratio (weight ratio) of propylene to the α-olefin is propylene / α-olefin = 70/30 to 100/0, preferably 80/30. 20 ~
100/0, more preferably 90/10 to 100/0
It is about. If the proportion of the α-olefin is too large, the rigidity and heat resistance decrease. The form of the copolymer may be any of a block copolymer and a random copolymer. Preferably, it is a propylene homopolymer. The stereoregularity in the polypropylene resin is not particularly limited, and examples thereof include isotactic, syndiotactic, atactic, and metallocene structures generated by a metallocene catalyst.
From the viewpoint of simplicity and economy, an isotactic structure that has been widely used in the past is preferable.

The MFR of the component (A ₂ ) is 0.3 to 30 g /
It is 10 minutes, preferably about 0.5 to 20 g / 10 minutes, and more preferably about 1 to 15 g / 10 minutes. In addition, MFR
Is based on JIS K 7210 according to JIS K 7210.
Condition 14 in Table 1 of 10 (test temperature 230 ° C., test load 2
1.18N). At least (A ₁ )
In order for the component to form a continuous phase, the MF of the component (A ₁ )
Preferably, R is higher than the MFR of the component (A ₂ ).

The ratio (weight ratio) of the component (A ₁ ) to the component (A ₂ ) is (A ₁ ) / (A ₂ ) = 5/95 to 70/30, preferably 10/90 to 50/50. , More preferably 1
It is about 5/85 to 45/55.

(B) Conductive agent As the component (B), carbon powder (conventional artificial graphite powder,
Expanded graphite powder, natural graphite powder, coke powder, conductive carbon black, etc.), carbon fiber, metal powder, etc.
Among these, conductive carbon black is preferably used. These conductive agents can be used alone or in combination of two or more.

Examples of the conductive carbon black include furnace black, channel black, gas black, acetylene black, arc black and the like. Among these conductive carbon blacks, furnace black having a large specific surface area and excellent conductivity, particularly Ketjen black, is preferred. Further, a conductive composite carbon black obtained by combining these conductive carbon blacks may be used. The specific surface area of the conductive carbon black is 1
00~1500m ² / g, especially 500~1500m ² / g
The degree is preferred.

The average particle size of the conductive agent (especially conductive carbon black) has a close relationship with the ratio of the component (A) and cannot be specified unconditionally, but is usually 1 nm to 10 μm, preferably 5 nm to 1 μm. More preferably, 10 to 100 n
m.

Conductive agent (especially conductive carbon black)
Is contained in the component constituting the continuous phase among the components (A ₁ ) and (A ₂ ). For example, the component (A ₁ ) is a high-density polyethylene, and the component (A ₂ ) is a polypropylene resin. In some cases, the component (B) is contained in the continuous phase composed of the component (A ₁ ).

The proportion of the component (B) is 1 in total of the component (A).
0.1 to 30 parts by weight (e.g.,
0.5 to 20 parts by weight), preferably about 1 to 20 parts by weight (for example, 2 to 20 parts by weight), and more preferably about 3 to 15 parts by weight (particularly 5 to 15 parts by weight). If the proportion of the component (B) is too small, the conductivity becomes insufficient. If the proportion is too large, the processability and the mechanical properties of the resin deteriorate.

In the skin layer, if necessary, an antistatic agent (a surfactant having a weight average molecular weight of 3000 or less), a coloring agent, a dispersant, a release agent, and a stabilizer (an antioxidant, an ultraviolet absorber) , A heat stabilizer, etc.), a flame retardant, a lubricant, an antiblocking agent, a filler, an antifoaming agent, a coating improver, a thickener and the like.

[Base Sheet] As the thermoplastic resin constituting the base sheet, the same resins as those exemplified in the section of the skin layer can be used. Among the thermoplastic resins, a resin of the same type as the component (A ₁ ) or the component (A ₂ ) constituting the skin layer is preferable. When a resin of the same type as the component (A ₁ ) or the component (A ₂ ) is used, good adhesiveness can be obtained without the need for an adhesive.

As a preferred combination, the skin layer is composed of a polyolefin resin, and the base sheet is composed of a polyolefin resin, particularly a thermoplastic resin containing a polypropylene resin having excellent heat resistance and mechanical properties. preferable. When the base sheet is a resin containing a polypropylene resin, a polystyrene resin or a rubber-like polymer may be combined in order to further improve the rigidity and moldability of the sheet. For example, a preferable combination may be a combination of a polypropylene resin, a polystyrene resin (polystyrene and / or high impact polystyrene), and a diene rubber (styrene-butadiene block copolymer or the like). When combined with another thermoplastic resin, the polypropylene-based resin is 1
The content is preferably 0% by weight or more, particularly preferably 20% by weight or more.

The conventional additives exemplified in the section of the skin layer may be added to the base sheet. The base sheet mainly plays a role of reinforcing the stiffness and mechanical properties of the sheet, and therefore, among the additives, fillers (talc, mica, glass fiber, glass flake, calcium carbonate, etc.).
Is 1 to 50 parts by weight, preferably 3 to 40 parts by weight, more preferably 5 to 50 parts by weight, based on 100 parts by weight of the thermoplastic resin.
About 30 parts by weight may be added.

[Laminated Sheet] In the laminated sheet, a skin layer is laminated on at least one surface of the base sheet, and depending on the application, it may be sufficient to laminate the skin layer on only one surface. It is preferable that both surfaces of the material sheet are laminated with a skin layer. The ratio of the thickness between the base sheet and each skin layer is as follows: base sheet / skin layer = 30/1 to 1 /
1, preferably 20/1 to 2/1, more preferably 1
It is about 5/1 to 5/1. The thickness of each skin layer is 5
It is about 500 μm, preferably about 10 to 300 μm, more preferably about 20 to 200 μm (particularly about 30 to 100 μm). The thickness of the substrate sheet is 50 to 5000 μm, preferably 100 to 3000 μm, and more preferably 20 to 5000 μm.
It is about 0 to 2000 μm (particularly 300 to 1000 μm). The thickness of the entire laminated sheet is 0.01 to 5 mm, preferably 0.1 to 3 mm, and more preferably 0.5 to 1 mm.
mm.

[Dupont Impact Strength] The conductive sheet of the present invention has a DuPont impact strength of 0.5 N · m or more, preferably 0.5 to 0.5 Nm at a sheet thickness of 0.7 mm.
It is about 10 N · m, more preferably about 0.5 to 5 N · m, and is extremely excellent in impact resistance.

[Surface resistivity] The conductive sheet of the present invention has a surface resistivity of 1 to 10 ¹⁰ Ω / □, preferably 10 ¹⁰ Ω / □.
~10 ⁸ Ω / □, more preferably 10 ² ~10 ⁶ Ω / □
(Particularly about 10 ² to 10 ⁵ Ω / □), which is very excellent in conductivity.

[Manufacturing Method of Laminated Sheet] The skin layer and the base sheet are not particularly limited, and can be manufactured by mixing the respective components and then forming into a sheet by a conventional method. For example, the extrusion method [die (flat shape, T shape (T die), cylindrical shape (circular die), etc.))
Method, inflation method, etc.], a stretching method by a tenter method, a tube method, an inflation method and the like. The resin sheet may be stretched (uniaxial stretching, biaxial stretching, etc.) or may be unstretched. The laminated sheet may be prepared by a method such as heat lamination or dry lamination of the obtained sheet, but it is preferable to prepare the skin layer and the base sheet by a co-extrusion method. In the lamination method,
No adhesive is required.

[Secondary molded article] The sheet obtained in this manner is subjected to secondary molding by conventional blow molding such as free blow molding, vacuum molding, bending, air pressure molding, match molding and hot plate molding. can do. Examples of the secondary molded product include packaging materials, food containers, chemical containers, trays, embossed tapes or carrier tapes, and magazines.

The surface of the sheet or the secondary molded article may be subjected to a surface treatment (for example, discharge treatment such as corona discharge or glow discharge, acid treatment, flame treatment, etc.). The surface of the sheet or the secondary molded article may be further subjected to a conductive treatment or an antistatic treatment (for example, application or kneading of an antistatic agent, a conductivity imparting agent such as a metal oxide) or a conductive coating or an antistatic layer (for example, Etc.) may be formed.

The sheet of the present invention is excellent in the antistatic property and its resilience, does not fall off carbon black, and is excellent in various properties such as heat resistance, appearance and mechanical properties. Useful for packaging materials for semiconductors and electronic components, molded products for transportation having housing recesses for housing semiconductors and electronic components (for example, trays for transporting electronic components, carrier tapes, etc.), and packaging materials for electronic components such as liquid crystals It is.

[0040]

According to the present invention, a conductive sheet having excellent mechanical properties such as impact resistance can be obtained. This conductive sheet is excellent in the appearance and formability of the sheet surface, and the conductive agent is less likely to fall off the sheet surface. Therefore, it is useful in the field of packaging materials for semiconductors and electronic parts that require high antistatic properties.

[0041]

EXAMPLES The present invention will be described in more detail with reference to the following Examples, but it should not be construed that the invention is limited thereto. The content of each component used in the following examples and the method of measuring the evaluation items are as follows.

[High Density Polyethylene] HDPE-1: Nipolon Hard 250, manufactured by Tosoh Corporation
0 (MI = 8 g / 10 min, solubility parameter 16.4) HDPE-2: Nipolon Hard 100 manufactured by Tosoh Corporation
0 (MI = 20 g / 10 min, solubility parameter 16.
4).

[Polypropylene resin] PP-1: J104W (M
I = 5 g / 10 min, solubility parameter 19.2) PP-2: J105WT, manufactured by Grand Polymer Co., Ltd.
(MI = 13 g / 10 min, solubility parameter 19.2) PP-3: manufactured by Grand Polymer Co., Ltd., B101WA
(MI = 0.5 g / 10 min) PP-4: F109D (M, manufactured by Grand Polymer Co., Ltd.)
I = 9 g / 10 min).

[Carbon Black] CB-1: manufactured by Lion Corporation, Ketjen Black EC CB-2: Cabot Specialty Chemicals Co., Ltd.
Vulcan XC-72, manufactured by Ink Corporation.

[Polystyrene resin] GPPS: Toyo Styrene Co., Ltd., G340C HIPS: Toyo Styrene Co., Ltd., E850 [Styrene thermoplastic elastomer] SBS: JSR Co., Ltd., TR2003 [Filler]: Talc .

[Surface resistivity] According to JIS K 7194, the surface resistivity (Ω) of the sheet was measured using a low resistivity meter.
/ □) was measured.

[Surface Appearance] The size of the convex foreign matter on the sheet surface was measured and evaluated according to the following criteria.

○: There is no foreign matter of 1 mm or more. X: There is foreign matter of 1 mm or more.

[Non-dropping property of carbon] Length 20 cm × width 2
Fix a 0cm sheet, and place 30m of copy paper on it
The paper was reciprocated 10 times in m spans, and the color change of the copy paper due to friction was visually observed and evaluated according to the following criteria.

：: no carbon adhesion ×: carbon adhesion

[Impact Resistance] The DuPont impact strength of the sheet was measured according to JIS K 7211 and evaluated according to the following criteria.

：: Impact strength of 0.5 N · m or more ×: Impact strength of less than 0.5 N · m

Examples 1 to 8 and Comparative Examples 1 to 4 The components constituting the skin layer were blended according to the composition shown in Table 1.
The mixture was kneaded with a twin-screw extruder (L / D = 20), extruded into strands and cut to prepare pellets. The components constituting the core layer were dry-blended with a composition shown in Table 1 using a tumbler.

The first single screw extruder (screw diameter 50 mm, L / D = 25) of the multilayer extruder (two-type three-layer extruder)
The pellets constituting the skin layer are heated at a cylinder temperature of 230 ° C
And a second single screw extruder (screw diameter 65 mm,
(L / D = 32), the resin composition constituting the core layer is supplied at a cylinder temperature of 210 ° C., the skin layers are joined on both sides of the core layer in the feed block, and laminated, and a sheet is formed by a T-die casting method. After being extruded into a shape, it is cooled by a cooling roll to a total thickness of 700 μm (thickness ratio: skin layer /
A laminated sheet of (core layer / skin layer = 1/10/1) was obtained. Table 1 shows the evaluation results of the laminated sheet.

Comparative Example 5 A single-layered sheet having the same composition as that of the skin layer of Example 4 and having a thickness of 700 μm was obtained by a T-die casting method using an extruder (screw diameter: 65 mm, L / D = 32). Table 1 shows the evaluation results of this sheet.

[0056]

[Table 1]

From the results shown in Table 1, the sheets of Examples 1 to 8 have a low surface resistivity, a small amount of carbon black falling off, and are excellent in surface appearance and impact resistance. On the other hand, the sheets of Comparative Examples 1 and 2 have a high surface specific resistance value, and the sheets of Comparative Examples 3 and 4 have a sharp dropout of carbon black, and have insufficient surface appearance and impact resistance. In the sheet of Comparative Example 5, the carbon black fell off sharply and the impact resistance was not sufficient.

Further, for the sheets of Example 1 and Comparative Example 2, an electron micrograph (2500) of the cross section of the skin layer was obtained.
1 and 2 are shown in FIGS. In FIG.
The dark portion is a continuous phase of high-density polyethylene and carbon black, and the light-colored portion is a continuous phase of polypropylene, forming a bicontinuous structure. In FIG. 2, the dark portion is the dispersed phase of carbon black, and the light portion is the continuous phase of polypropylene, forming a sea-island structure.

[Brief description of the drawings]

FIG. 1 is a schematic drawing of an electron micrograph (2500 times) of a cross section of a skin layer in a sheet of Example 1.

FIG. 2 is a simulated view of an electron micrograph (2500 times) of a cross section of a skin layer in a sheet of Comparative Example 2.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification code FI theme coat ゛ (reference) C08L 101/00 C08L 101/00 F term (reference) 4F100 AA37A AA37C AC10 AK01A AK01B AK01C AK03B AK05A AK05B AK05C AK07A AK07B AK07C AK73 AL05A AL05B AL05C BA03 BA06 BA10A BA10C CA21A CA21C EH20 GB15 GB41 JB16A JB16B JB16C JG01 JG03 JK10 JK10A JK10C YY00A YY00B YY00C 4J002 AA011 BB03W BB11G BB12G BB12X BB12X BB12G

Claims (15)

[Claims] 1. A sheet in which a skin layer composed of a thermoplastic resin (A) and a conductive agent (B) is laminated on at least one surface of a substrate sheet formed of a thermoplastic resin, In this skin layer, the thermoplastic resin (A)
It is composed of thermoplastic resins (A ₁ ) and (A ₂ ) having different solubilities, and has a difference [δ (A ₂ ) −δ (A ₁ ) of a solubility parameter between the component (A ₁ ) and the component (A ₂ ). ] Is 1.5 to 10 (MP
a) A conductive sheet that is ^1/2 and has a DuPont impact strength of 0.5 Nm or more at a sheet thickness of 0.7 mm. 2. In the skin layer, (A ₁ ) and (A ₂ )
The sheet according to claim 1, wherein at least one of the components forms a continuous phase, and component (B) is contained in the continuous phase. 3. In the skin layer, the component (A ₁ ) and the component (A ₂ ) form a co-continuous phase structure, and the component (B) is contained in the continuous phase composed of the component (A ₁ ). The sheet according to claim 1, wherein 4. The sheet according to claim 1, wherein the thermoplastic resin (A) comprises high-density polyethylene (A ₁ ) and polypropylene-based resin (A ₂ ). 5. The sheet according to claim 1, wherein the conductive agent (B) is conductive carbon black. 6. The ratio (weight ratio) of the component (A ₁ ) to the component (A ₂ ) is (A ₁ ) / (A ₂ ) = 5/95 to 70/30, and the component (B) Of the component (A) is 10
The sheet according to claim 1, wherein the amount is 0.1 to 30 parts by weight based on 0 part by weight. 7. The thermoplastic resin constituting the base sheet,
Constituting the skin layer (A ₁₎ component or (A ₂₎ component and the sheet of claim 1, wherein the resin or sheet of the same strain. 8. The sheet according to claim 2, wherein the thermoplastic resin constituting the base sheet contains a polyolefin resin. 9. The sheet according to claim 1, wherein skin layers are laminated on both sides of the base sheet. 10. The sheet according to claim 1, wherein the ratio of the thickness of the base sheet to each skin layer is 30/1 to 1/1. 11. The sheet according to claim 1, wherein each skin layer has a thickness of 5 to 500 μm. 12. The sheet according to claim 1, wherein the sheet has a surface resistivity of 1 to 10 ¹⁰ Ω / □. 13. A resin composition containing a polypropylene resin.
High-density polyethylene on both sides of the substrate sheet
(A₁), Polypropylene (A_Two) And conductive carbon
Sea with laminated skin layer composed of black (B)
And a surface resistivity of 1 to 10⁸Ω / □,
(A₁) Component and (A)_Two) Component (weight ratio)
(A₁) / (A_Two) = 10/90 to 50/50, (B)
The percentage of (A ₁) And (A_Two) 100 parts by weight of total components
0.5 to 20 parts by weight with respect to (A₁) Components
(A_Two) Component and the difference in solubility parameter [δ (A_Two)-
δ (A₁)] Is 1.7 to 5 (MPa).^1/2And the sheet thickness
0.5mm DuPont impact strength at 0.7mm
m, the ratio of the thickness of the base sheet and each skin layer,
Substrate sheet / skin layer = 20/1 to 2/1, and
A conductive sheet in which the thickness of each skin layer is 10 to 300 μm
G. 14. A molded article formed from the sheet according to claim 1. 15. The method of forming a sheet according to claim 1, wherein the skin layer and the base sheet are co-extruded by a co-extrusion method.