JP5139140B2 - Polyolefin resin sheet - Google Patents

Description

  The present invention relates to a polyolefin resin sheet having excellent impact resistance and excellent moldability, and a molded product thereof.

  Cyclic polyolefin resins are excellent in transparency, heat resistance, mechanical strength, and dimensional stability, and are used as materials for optical components such as lenses, optical disks, prisms, and sheets. When obtaining such a molded article of an optical component, a resin material outside the product remaining in the spool portion or the runner portion, an excess portion called an ear generated at both ends of the film or the sheet, or a waste material such as a nonstandard product is generated. Although these waste materials are also considered to be melted, pelletized, and reused, their transparency is lowered, so that it is difficult to reuse them for optical parts. Accordingly, incineration treatment and landfill treatment are generally performed, and other measures for effectively treating the waste material of the cyclic polyolefin resin are being sought.

  A sheet for thermoforming to which a cyclic polyolefin resin is added has also been proposed, but it is for improving the sag of a polypropylene resin sheet during thermoforming, and the resulting sheet and molded product have poor impact resistance. It was unsuitable as a sheet for packaging material or cushioning material (see Patent Document 1).

  Further, a resin composition of a diene polymer hydrogenated with a cyclic polyolefin resin and a polyolefin resin has been proposed, but in addition to the high cost of the hydrogenated diene polymer, the impact resistance is poor. Since it was sufficient, the obtained tray-shaped molded article was insufficient in impact resistance (see Patent Document 2).

  On the other hand, since cyclic polyolefin resin is generally a good electrical insulator, it is easy to be charged with static electricity. Therefore, when a sheet using a cyclic polyolefin resin is used for an electronic component packaging material, it is necessary to provide antistatic performance, but the cyclic polyolefin resin has a non-crystalline property and a high glass transition temperature. Has a problem that it is difficult to exhibit antistatic performance.

  Furthermore, since cyclic polyolefin is relatively brittle and difficult to mix with polypropylene resin, it is difficult to obtain a sheet having excellent impact resistance and moldability simply by mixing with polypropylene resin and melt-kneading. there were.

JP2002-249625 JP-A-6-316653

  The present invention relates to a polyolefin resin sheet having excellent impact resistance and excellent molding processability, and a molded product thereof.

Therefore, as a result of intensive studies, the present inventors have found that an ethylene-α-olefin copolymer is used with respect to 100 parts by weight of a resin composition comprising 60 to 20% by weight of a polypropylene resin and 40 to 80% by weight of a cyclic polyolefin resin. 5-30 parts by weight of a resin is added, and an antistatic agent is further included. The specific surface resistivity is less than 1 × 10 ¹³ (Ω) when the temperature is 22 ° C. and the humidity is 65% in accordance with JIS K6911 5.13. It has been found that the above-mentioned problems can be solved by using a polyolefin resin sheet and a molded product thereof.

Thereby, it is possible to provide a polyolefin resin sheet having excellent impact resistance and excellent molding processability, and a molded product thereof. Therefore, even if a cyclic polyolefin-based resin is contained, it is suitable for use as a tray-shaped molded product in addition to a sheet for a packaging material or a cushioning material because of its excellent impact resistance as well as effective use of waste materials. In addition, when a sheet using a cyclic polyolefin resin is used as an electronic component packaging material, it contains an antistatic agent, and has a surface resistivity at a temperature of 22 ° C. and a humidity of 65% in accordance with JIS K6911 5.13. Is less than 1 × 10 ¹³ (Ω), it is possible to impart antistatic performance even to a polyolefin resin sheet containing a cyclic polyolefin resin.

Embodiments of the present invention will be described below.
(Polypropylene resin)
The polypropylene resin of the present invention is conventionally used, and is not particularly limited. For example, homopolypropylene, a block copolymer of propylene and a monomer copolymerizable therewith or a random copolymer, and the like. Can be mentioned.
Examples of the monomer copolymerizable with propylene include ethylene, 1-butene, isobutene, 1-pentene, 3-methyl-1-butene, 1-hexene, 4-methyl-1-pentene, 1-heptene, 1 Α-olefins such as octene and 1-decene, dienes such as 1,4-hexadiene, 5-methyl-1,4-hexadiene and 7-methyl-1,6-octadiene, vinyl chloride, vinylidene chloride, acrylonitrile, acetic acid Vinyl, acrylic acid, methacrylic acid, maleic acid, methyl acrylate, ethyl acrylate, butyl acrylate, methyl methacrylate, ethyl methacrylate, butyl methacrylate, maleic anhydride, styrene, methyl styrene, vinyl toluene, divinyl benzene, etc. Polyolefin sheet obtained by using Ethylene is preferred in that impact resistance is excellent.
And if there are few propylene components in the block copolymer or random copolymer of the said propylene and a monomer copolymerizable with this, the heat resistance of the polyolefin resin sheet obtained, rigidity, and impact resistance will fall. Therefore, 80% by weight or more is preferable, and 90% by weight or more is more preferable.

If the melt flow rate of the polypropylene resin is low, the extrusion processability during production may be reduced and productivity may be reduced. If the melt flow rate is high, the kneadability with the cyclic polyolefin resin may be reduced. 5 to 20 g / 10 min is preferable, and 1 to 10 g / 10 min is more preferable.
The melt flow rate of the polypropylene resin is an index representing the flow characteristics of the resin, and can be obtained by measuring according to JIS K7210. In the present invention, measurement is performed at 230 ° C. and a load of 2.16 kg from the point of using a polypropylene resin.

(Cyclic polyolefin resin)
The cyclic polyolefin resin of the present invention refers to a polyolefin resin having a cyclic aliphatic hydrocarbon in the main chain or side chain. Examples of the cyclic aliphatic hydrocarbon include those represented by the structural formula shown in “Chemical Formula 1”.

  Examples of commercially available cyclic polyolefin-based resins include ZEONEX (registered trademark) and ZEONOR (registered trademark) manufactured by ZEON Corporation, Arton (registered trademark) manufactured by JSR, APPEL (registered trademark) manufactured by Mitsui Chemicals, For example, Topas made by Polyplastics.

  More preferable cyclic polyolefin-based resins are those having a glass transition temperature of 100 ° C to 160 ° C. Within this range, good kneadability is exhibited when melt-mixed with polypropylene and an ethylene-α-olefin copolymer. In addition, the glass transition temperature of the said cyclic polyolefin-type resin is a midpoint glass transition temperature measured by the measuring method prescribed | regulated to JISK7121 using the differential scanning calorimeter (Seiko Denshi Kogyo RDC220 type | mold).

  Cyclic polyolefin resins include cycloolefin copolymer (COC) type obtained by copolymerizing norbornene and ethylene with a metallocene catalyst, and cycloolefin polymer (COP) type of metathesis ring-opening polymerization type. It doesn't matter.

Virgin raw materials may be used for the above cyclic olefin resin, but, for example, optical parts such as optical lenses and prisms, and crushed products of spool parts and runner parts that are generated when the optical parts are manufactured by injection molding or the like. Also, re-pellet products may be used.
The proportions of the polypropylene resin and the cyclic polyolefin resin are 60 to 20% by weight of the polypropylene resin and 40 to 80% by weight of the cyclic polyolefin resin. When the amount of polypropylene resin is more than 60% by weight, the amount of cyclic polyolefin used is small, which is not preferable from the viewpoint of recycling. Further, when the polypropylene resin is less than 20% by weight, the impact resistance and moldability are lowered, which is not preferable. More preferably, the proportion of the polypropylene resin is 60 to 40% by weight and the proportion of the cyclic polyolefin resin is 40 to 60% by weight.

(Ethylene-α-olefin copolymer resin)
Examples of the α-olefin of the ethylene-α-olefin copolymer resin include propylene, 1-butene, isobutene, 1-pentene, 3-methyl-1-butene, 1-hexene, 4-methyl-1-pentene, Examples include 1-heptene, 1-octene, 1-decene and the like.
The α-olefin has a high cost when its carbon number is large, and when the carbon number is small, the impact resistance of the resulting polyolefin resin sheet is lowered. Olefin is preferable, 1-butene, 1-hexene and 1-octene are more preferable, and 1-hexene is particularly preferable.

  Examples of the copolymer resin of ethylene and α-olefin having 4 to 8 carbon atoms include, for example, trade name “Excellen FX CX3502” (ethylene-1-butene copolymer) manufactured by Sumitomo Chemical Co., Ltd., Nippon Polyethylene Co., Ltd. Under the trade name “Kernel KS240T” (ethylene-1-hexene copolymer) and Dow Chemical Company under the trade name “engage EG8100” (ethylene-1-octene copolymer).

Furthermore, if the density of the ethylene-α-olefin copolymer resin is large, the impact resistance of the resulting polyolefin resin sheet is lowered, which is not preferable. Moreover, since the mechanical strength of the polyolefin-type resin sheet and rigidity at high temperature may fall when it is small, 0.85-0.91 g / cm < ³ > is preferable, 0.86-0.88 g / cm ³ is more preferable.

  And if there is little content of the said ethylene-alpha-olefin copolymer, the impact resistance of the polyolefin-type resin sheet obtained will fall, and when large, the mechanical strength of the polyolefin-type resin sheet obtained, and at the time of high temperature This is not preferable because the rigidity of the resin decreases. Accordingly, the ethylene-α-olefin copolymer resin is limited to 5 to 30 parts by weight with respect to 100 parts by weight of the resin composition comprising 60 to 20% by weight of the polypropylene resin and 40 to 80% by weight of the cyclic polyolefin resin. The amount is preferably 10 to 30 parts by weight, more preferably 10 to 20 parts by weight. By including the ethylene-α-olefin copolymer resin, the effect of the antistatic agent is enhanced.

(Antistatic agent)
As the antistatic agent used in the present invention, any one of a polymer type antistatic agent and a surfactant type antistatic agent can be used.

  The polymer type antistatic agent of the present invention is a polymer type antistatic agent called, for example, a long-lasting antistatic agent or a permanent antistatic agent, and specifically includes polyethylene oxide, polypropylene oxide, polyethylene glycol. A polyester amide, a polyether ester amide, a polyether polyolefin, an ionomer such as an ethylene-methacrylic acid copolymer, a quaternary ammonium salt such as a polyethylene glycol methacrylate copolymer, Or a mixture of two or more kinds, or two or more kinds of copolymers, and copolymers thereof with other resins such as polypropylene, etc., having a polar group in the molecular chain, or an inorganic salt or low molecular weight organic Examples include resins capable of complexing or solvating protonic acid salts such as inorganic salts or organic protonic acid salts. It may be complexed or solvated. Of these, polyether polyolefin and polyether ester amide are preferred, and polyether polyolefin is particularly preferred from the viewpoint of compatibility with polypropylene resin and cyclic polyolefin resin and antistatic performance.

  The polymer type antistatic agent is preferably 10 to 20 parts by weight with respect to 100 parts by weight of a resin composition comprising 60 to 20% by weight of a polypropylene resin and 40 to 80% by weight of a cyclic polyolefin resin. If the amount of the polymer type antistatic agent is less than 10 parts by weight, stable predetermined antistatic performance cannot be obtained, and if it is more than 20 parts by weight, the extrusion processability is lowered, and the improvement in antistatic performance is not recognized so much. This is not preferable because it increases costs.

  Moreover, a conventionally well-known compound can be used as surfactant type antistatic agent of this invention. For example, cationic surfactants typified by quaternary ammonium salts, pyridine derivatives, alkyl sulfate esters, alkyl aromatic sulfonates, succinate sulfonates, phosphate esters, and the like , Partial fatty acid ester of polyhydric alcohol and its ethylene oxide adduct, ethylene oxide adduct of aliphatic alcohol, ethylene oxide adduct of aliphatic amine, ethylene oxide adduct of fatty acid amide, ethylene oxide adduct of alkylphenol or alkylnaphthol Nonionic surfactants typified by, amphoteric surfactants typified by betaine-type carboxylic acid derivatives, imidazoline derivatives, etc., are used alone or in combination. Of these, nonionic surfactants are preferred in the present invention from the viewpoints of effects, ease of handling, and safety to the human body.

  The nonionic surfactant type antistatic agent is not particularly limited. For example, an alcoholic antistatic agent such as polyethylene glycol, an ether-based charging agent such as polyoxyethylene alkyl ether or polyoxyalkylene alkyl ether, and the like. Antistatic agents, sorbitan fatty acid esters, polyoxyethylene sorbitan fatty acid esters, polyoxyethylene sorbitol fatty acid esters, ester antistatic agents such as glycerin fatty acid esters, amine-based antistatic agents such as polyoxyethylene alkylamine, polyoxyethylene glycerides, etc. Glycerin-based antistatic agents and amide-based antistatic agents such as alkyl alkanolamides. Alcohol-based antistatic agents and amine-based antistatic agents are preferred because of their high bleed-out speed. Glycol, polyoxyethylene alkylamines are more preferred, and polyoxyethylene alkyl amine is particularly preferred. The nonionic surfactant type antistatic agent may be used alone or in combination.

  If the amount of the surfactant type antistatic agent added is large, the surface of the resulting polyolefin resin sheet becomes sticky, and if it is small, the antistatic performance of the resulting polyolefin resin sheet is insufficient. The amount is preferably 0.2 to 5 parts by weight, more preferably 1 to 4 parts by weight with respect to 100 parts by weight of the resin composition comprising 60 to 20% by weight of the resin based on resin and 40 to 80% by weight of the cyclic polyolefin resin.

  In the present invention, if necessary, a colorant or a light blocking agent may be added. Such colorants and light blocking agents include, for example, inorganic materials such as carbon black, titanium oxide, zinc oxide, iron oxide, aluminum oxide, cyanine blue, cyanine green, miloli blue, selenium blue, cadmium red, cadmium yellow, cadmium orange. And pigments such as petals, ultramarine blue, and phthalocyanine blue. These may be added directly, but it is preferable to use a master batch from the viewpoint of workability. The base resin of the master batch is preferably LDPE or PP.

  Moreover, you may add stabilizers, such as antioxidant, a deterioration inhibitor, and an ultraviolet absorber, as needed.

(Production method)
The polyolefin-based resin sheet of the present invention can be obtained by melt-kneading the resin composition and the antistatic agent in an extruder and extruding it into the atmosphere from a mold attached to the tip of the extruder. More specifically, a manufacturing method in which a T-die is attached to the tip of the extruder and a sheet extruded therefrom is formed by a cooling drum (cooling roll), or a circular die is attached to the tip of the extruder and extruded from there. Either of the manufacturing methods in which a sheet-like sheet is formed with a mandrel and then cut into a sheet form can be applied.

The polyolefin resin sheet of the present invention has a surface resistivity of less than 1 × 10 ¹³ (Ω) when the temperature is 22 ° C. and the humidity is 65% in accordance with JIS K6911 5.13. If the surface specific resistance value exceeds 1 × 10 ¹³ (Ω), the package may be destroyed by static electricity when used as a packaging material for electronic components.

  The range of 0.3-3 mm is preferable and, as for the thickness of the polyolefin resin sheet of this invention, the range of 0.5-2 mm is more preferable. When the thickness of the sheet is less than 0.3 mm, the moldability is poor and the strength of the molded product may be insufficient. Those exceeding 3 mm are not preferable because the moldability is poor and the molded product becomes heavy.

Hereinafter, the present invention will be described in detail based on examples and comparative examples.
Example 1
To 60 parts by weight of a polypropylene resin (BC6C manufactured by Nippon Polypro Co., Ltd.) having a melt flow rate of 2.5 g / 10 min and 40 parts by weight of a cyclic polyolefin (ZEONEX 480R manufactured by Nippon Zeon Co., Ltd.) having a glass transition temperature of 138 ° C. 20 parts by weight of ethylene-α-olefin copolymer resin (Nippon Polyethylene Kernel KS240T) having a density of 0.88 g / cm ³ , nonionic surfactant (polyoxyethylene alkylamine type nonionic surfactant) 2 parts by weight of (agent) (TS-2B manufactured by Kao Corporation) was added and mixed with a blender. Thereafter, the cylinder was supplied to a single screw extruder (a single screw extruder having a diameter of 65 mmφ (L / D = 37)) maintained at 220 ° C. and melted and kneaded in the cylinder.
Next, it was extruded downward from a T-die (width 300 mm, slit width 0.6 mm) connected to this extruder, and the temperature was adjusted with water at 30 ° C. Two coolings with a diameter of 150 mmφ laid at 100 mm from the T-die The extruded melt was cooled and solidified with a drum (drum interval 1.0 mm, drum cooling temperature 40 ° C.) to obtain a polyolefin sheet. The obtained sheet had a width of 270 mm and a thickness of 1.0 mm.
The resulting sheet is heated in an oven so that the surface temperature becomes 170 ° C., and then pressed with a cup-shaped matched mold made of aluminum, and after 10 seconds, the matched mold is released and released. The type was confirmed. The molded product did not attach to the matched mold or was not torn, and the mold release and moldability were good.

(Example 2)
A polyolefin sheet was obtained in the same manner as in Example 1 except that the proportion of the polypropylene resin was 20 parts by weight and the proportion of the cyclic polyolefin resin was 80 parts by weight. The obtained sheet had a width of 280 mm and a thickness of 1.0 mm.
The resulting sheet is heated in an oven so that the surface temperature becomes 170 ° C., and then pressed with a cup-shaped matched mold made of aluminum, and after 10 seconds, the matched mold is released and released. The type was confirmed. The molded product did not attach to the matched mold or was not torn, and the mold release and moldability were good.

(Example 3)
A polyolefin sheet was obtained in the same manner as in Example 1 except that the addition amount of the ethylene-α-olefin copolymer resin was 10 parts by weight. The obtained sheet had a width of 270 mm and a thickness of 1.0 mm.
The resulting sheet is heated in an oven so that the surface temperature becomes 170 ° C., and then pressed with a cup-shaped matched mold made of aluminum, and after 10 seconds, the matched mold is released and released. The type was confirmed. The molded product did not attach to the matched mold or was not torn, and the mold release and moldability were good.

Example 4
A polyolefin sheet was obtained in the same manner as in Example 1 except that the addition amount of the antistatic agent was 0.3 parts by weight. The obtained sheet had a width of 270 mm and a thickness of 1.0 mm.
The resulting sheet is heated in an oven so that the surface temperature becomes 170 ° C., and then pressed with a cup-shaped matched mold made of aluminum, and after 10 seconds, the matched mold is released and released. The type was confirmed. The molded product did not attach to the matched mold or was not torn, and the mold release and moldability were good.

(Example 5)
A polyolefin-based sheet was obtained in the same manner as in Example 1 except that the addition amount of the antistatic agent was 4 parts by weight. The width of the obtained sheet was 270 mm and the thickness was 1.0 mm.
The obtained sheet is heated in an oven so that the surface temperature becomes 170 ° C., then pressed with a cup-shaped matched mold made of aluminum, and then the mold is released after 10 seconds to confirm the releasability. did. The molded product did not attach to the matched mold or was not torn, and the mold release and moldability were good.

(Example 6)
A polyolefin-based sheet was obtained in the same manner as in Example 1 except that the antistatic agent was an anionic surfactant (sodium alkyl sulfonate) (ELECON SS700 manufactured by Dainichi Seika Co., Ltd.). The width of the obtained sheet was 270 mm and the thickness was 1.0 mm.
The obtained sheet is heated in an oven so that the surface temperature becomes 170 ° C., then pressed with a cup-shaped matched mold made of aluminum, and then the mold is released after 10 seconds to confirm the releasability. did. The molded product did not attach to the matched mold or was not torn, and the mold release and moldability were good.

(Example 7)
A polyolefin sheet was prepared in the same manner as in Example 1 except that 12 parts by weight of a polymer type antistatic agent (polyether polyolefin type polymer antistatic agent) (Pelestat 300 manufactured by Sanyo Kasei Co., Ltd.) was added as an antistatic agent. Obtained. The obtained sheet had a width of 280 mm and a thickness of 1.0 mm.
The obtained sheet is heated in an oven so that the surface temperature becomes 170 ° C., then pressed with a cup-shaped matched mold made of aluminum, and then the mold is released after 10 seconds to confirm the releasability. did. The molded product did not attach to the matched mold or was not torn, and the mold release and moldability were good.

(Example 8)
A polyolefin-based sheet was obtained in the same manner as in Example 7 except that 20 parts by weight of the antistatic agent was added. The width of the obtained sheet was 280 mm and the thickness was 1.0 mm.
The obtained sheet is heated in an oven so that the surface temperature becomes 170 ° C., then pressed with a cup-shaped matched mold made of aluminum, and then the mold is released after 10 seconds to confirm the releasability. did. The molded product did not attach to the matched mold or was not torn, and the mold release and moldability were good.

(Comparative Example 1)
A polyolefin sheet was obtained in the same manner as in Example 1 except that the ethylene-α-olefin copolymer resin was not added. The obtained sheet had a width of 270 mm and a thickness of 1.0 mm.
The resulting sheet is heated in an oven so that the surface temperature becomes 170 ° C., and then pressed with a cup-shaped matched mold made of aluminum, and after 10 seconds, the matched mold is released and released. The type was confirmed. The molded product did not attach to the matched mold or was not torn, and the mold release and moldability were good.

(Comparative Example 2)
A polyolefin sheet was obtained in the same manner as in Example 1 except that the proportion of the polypropylene resin was 10 parts by weight and the proportion of the cyclic polyolefin resin was 90 parts by weight. The obtained sheet had a width of 280 mm and a thickness of 1.0 mm.
The resulting sheet is heated in an oven so that the surface temperature becomes 170 ° C., and then pressed with a cup-shaped matched mold made of aluminum, and after 10 seconds, the matched mold is released and released. The type was confirmed. The molded product was stuck to the matched mold and then released, so wrinkles were found everywhere. Further, the sheet elongation at the time of the matched-type pressing was poor, and streaky tearing occurred at the cup side wall.

(Comparative Example 3)
A polyolefin-based sheet was obtained in the same manner as in Example 1 except that the addition amount of the antistatic agent was 0.1 parts by weight. The obtained sheet had a width of 270 mm and a thickness of 1.0 mm.
The obtained sheet is heated in an oven so that the surface temperature becomes 170 ° C., then pressed with a cup-shaped matched mold made of aluminum, and then the mold is released after 10 seconds to confirm the releasability. did. The molded product did not attach to the matched mold or was not torn, and the mold release and moldability were good.

(Comparative Example 4)
A polyolefin-based sheet was extruded in the same manner as in Example 1 except that the addition amount of the antistatic agent was 7 parts by weight. However, the antistatic agent slips at the raw material supply part during extrusion, and it is difficult to obtain a sheet stably. Further, the surface of the temporarily obtained sheet was sticky.

(Comparative Example 5)
A polyolefin-based sheet was extruded in the same manner as in Example 7 except that the addition amount of the antistatic agent was 8 parts by weight. The obtained sheet had a width of 280 mm and a thickness of 1.0 mm.
The obtained sheet is heated in an oven so that the surface temperature becomes 170 ° C., then pressed with a cup-shaped matched mold made of aluminum, and then the mold is released after 10 seconds to confirm the releasability. did. The molded product did not attach to the matched mold or was not torn, and the mold release and moldability were good.

  Table 1 below summarizes the sheet width, sheet thickness, surface intrinsic low efficiency, perforation impact value, and moldability during thermoforming of Examples 1 to 8 and Comparative Examples 1 and 2. In any case, it is recognized that the examples are better than the comparative examples.

[Each measurement method]
(Surface specific resistivity)
Surface specific resistivity measuring device (measured in accordance with JIS K6911 5.13 using a trade name “ULTRA HIGH RESISTANCE METER” manufactured by ADVANTEST Co. After being left for 24 hours in an atmosphere of 22 ° C. and 65% humidity, this test piece is set in a surface resistivity measuring apparatus, a voltage of 500 V is applied to the test piece, and the surface resistivity after one minute has elapsed. It was measured.

(Drilling impact value)
The test piece was measured in accordance with JIS P 8134, which is a paperboard impact punching strength test (piercing impact test), except that a 150 mm square foam was used. The number of tests was 10, and the average value was taken.

(Releasability during thermoforming)
After press forming a sheet heated to a surface temperature of 170 ° C in a vertical cup-shaped matched mold having a φ100 mm opening and a φ80 mm bottom and a depth of 150 mm, the matched mold is released after 10 seconds. Then, the releasability was confirmed visually. When the mold release from the matched mold is good at the time of mold release, the mold release property ○, when the mold release from the matched mold is bad, wrinkles or a cup of the predetermined depth is not obtained Releasability x. In addition, the case where the molded product is torn is indicated by x, and the case where it is not is indicated by ◯. Both were confirmed visually.

Claims (4)

With respect to 100 parts by weight of a resin composition comprising 60 to 20% by weight of a polypropylene resin and 40 to 80% by weight of a cyclic polyolefin resin,
And 5 to 30 parts by weight of an ethylene-α-olefin copolymer resin,
Contains antistatic agents,
JIS K6911 5.13 Temperature 22 ° C. conforming to, Ri surface resistivity is 1 × ^{10 13} (Ω) under der when the 65% humidity,
The polyolefin resin sheet, wherein the α-olefin of the ethylene-α-olefin copolymer resin is an α-olefin having 4 to 8 carbon atoms .   2. The polyolefin resin sheet according to claim 1, wherein the antistatic agent is a nonionic surfactant type antistatic agent.   The nonionic surfactant type antistatic agent is 0.2 to 5 parts by weight with respect to 100 parts by weight of a resin composition comprising 60 to 20% by weight of a polypropylene resin and 40 to 80% by weight of a cyclic polyolefin resin. The polyolefin resin sheet according to claim 2. A polyolefin resin sheet molded article obtained by thermoforming the polyolefin resin sheet according to any one of claims 1 to 3.