Antistatic masterbatch, antistatic resin composition, and antistatic resin molded body

Abstract

To provide an antistatic masterbatch which can produce a resin composition or a resin molding having excellent antistatic properties in a short time until an effective antistatic effect is exhibited even when a polypropylene resin or a low-density polyethylene resin is used as a diluent resin. [Solution] An antistatic masterbatch comprising at least one base resin selected from the group consisting of homopolypropylene resin, ethylene-propylene random copolymer, and low-density polyethylene resin, a donor-acceptor type antistatic agent, and a bleed effect agent, wherein the bleed effect agent is at least one selected from the group consisting of long-chain aliphatic alcohols, long-chain aliphatic esters, and surfactants, the content of the antistatic agent is 5 to 25 mass%, the content of the bleed effect agent is 0.5 to 15 mass%, and the amount of the bleed effect agent per part by mass of the antistatic agent is 0.1 to 1 part by mass.

Description

[Technical field]

[0001] The present invention relates to an antistatic masterbatch, an antistatic resin composition, and an antistatic resin molded article. [Background technology]

[0002] Since resins such as plastics have high electrical insulation properties, resin molded bodies (resin molded bodies) are prone to become charged and generate static electricity, which can easily cause problems such as equipment failure and fire. In order to avoid such problems, resin compositions containing surfactant-type antistatic agents (Patent Document 1), polymer-type antistatic agents (Patent Document 2), and donor-acceptor-type antistatic agents (Patent Document 3), as well as various molded bodies produced using such compositions, have been proposed.

[0003] It is known that surfactant-type antistatic agents exert an antistatic effect by adding a small amount, but the effect is deactivated relatively quickly. In addition, polymer-type antistatic agents do not exert an antistatic effect unless they are kneaded into the resin at a high concentration, so the physical properties of the resin itself are easily damaged. In contrast, donor-acceptor-type antistatic agents exert an antistatic effect semi-permanently by adding a small amount, so it is possible to manufacture various resin molded products that can exert a good antistatic effect for a long period of time without damaging the physical properties of the resin itself. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2010-280841 A [Patent Document 2] JP 2004-256778 A [Patent Document 3] JP 2023-32969 A Summary of the Invention [Problem to be solved by the invention]

[0005] However, donor-acceptor type antistatic agents are unlikely to exhibit effective antistatic effects unless they migrate to the surface of a resin composition or a resin molded product. For this reason, when a master batch containing a high concentration of donor-acceptor type antistatic agent is diluted with a diluent resin to produce a resin composition or molded product, it takes a considerable amount of time for the antistatic effect to appear, depending on the type of resin. Specifically, it was found that when polypropylene resin or low-density polyethylene resin is used, it takes a long time for the antistatic effect to appear.

[0006] The present invention has been made in consideration of the problems associated with such conventional techniques, and an object of the present invention is to provide an antistatic masterbatch which, even when a polypropylene resin or a low-density polyethylene resin is used as a diluent resin, can produce a resin composition or a resin molding having excellent antistatic properties in a short time until an effective antistatic effect is exhibited.

[0007] Another object of the present invention is to provide an antistatic resin composition and an antistatic resin molded article which are obtained by using the above-mentioned antistatic masterbatch and which have excellent antistatic properties and which take a short time to exhibit an effective antistatic effect. [Means for solving the problem]

[0008] That is, according to the present invention, there is provided the following antistatic masterbatch. [1] An antistatic masterbatch comprising at least one base resin selected from the group consisting of homopolypropylene resins, ethylene-propylene random copolymers, and low-density polyethylene resins, a donor-acceptor type antistatic agent, and a bleed effect agent, wherein the bleed effect agent is at least one selected from the group consisting of long-chain aliphatic alcohols, long-chain aliphatic esters, and surfactants, the content of the antistatic agent is 5 to 25 mass%, the content of the bleed effect agent is 0.5 to 15 mass%, and the amount of the bleed effect agent per part by mass of the antistatic agent is 0.1 to 1 part by mass. [2] The antistatic masterbatch according to [1], wherein the antistatic agent contains a compound represented by the following general formula (1):

[0009] TIFF0007631603000001.tif58170 (In the general formula (1), R1 and R2 each independently represent R7COOCH2- or HOCH2-, and at least one of them is R7COOCH2-; R3 and R4 each independently represent CH3-, C2H5-, HOCH2-, HOC2H4-, or HOCH2CH(CH3)-; R5 represents -C2H4- or -C3H6-; and R6 and R7 each independently represent an alkyl group having 11 to 21 carbon atoms.)

[0010] [3] The antistatic masterbatch according to [1] or [2], wherein the bleeding effect agent is at least one selected from the group consisting of stearyl alcohol, glycerin fatty acid ester, and alcohol ethoxylate.

[0011] According to the present invention, there is also provided the following antistatic resin composition. [4] An antistatic resin composition comprising the antistatic masterbatch according to any one of [1] to [3] above and at least one diluent resin selected from the group consisting of a homopolypropylene resin, an ethylene-propylene random copolymer, and a low-density polyethylene resin. [5] The surface resistivity (10 a1 The surface resistivity (10 Ω / sq) of a control resin composition having the same composition as the antistatic resin composition except that it does not contain the bleeding effect agent is a multiplier a1. a2The antistatic resin composition according to the above item [4], wherein a 99% charge decay time α1 (seconds) of the antistatic resin composition having an antistatic agent content of 0.75% by mass and a multiplier a2 of the charge decay time Ω / sq satisfy the relationship of the following formula (A1), and a 99% charge decay time α1 (seconds) of the antistatic resin composition having an antistatic agent content of 0.75% by mass and a 99% charge decay time α2 (seconds) of a control resin composition having the same composition as the antistatic resin composition except that it does not contain the bleed effect agent satisfy the relationship of the following formula (A2). 0.6≦a2-a1≦3 (A1) 80≦α2-α1≦118 (A2) [6] The surface resistivity (10 b1 The surface resistivity (10 Ω / sq) of a control resin composition having the same composition as the antistatic resin composition except that it does not contain the bleeding effect agent is multiplied by b1. b2 The antistatic resin composition according to the above item [4], wherein a 99% charge decay time β1 (seconds) of the antistatic resin composition having an antistatic agent content of 0.75% by mass and a multiplier b2 of the charge decay time β2 (seconds) of a control resin composition having the same composition as the antistatic resin composition except that it does not contain the bleed effect agent satisfy the relationship of the following formula (B2): 0.3≦b2-b1≦1 (B1) 6≦β2-β1≦12 (B2) [7] The surface resistivity (10 c1 The surface resistivity (10 Ω / sq) of a control resin composition having the same composition as the antistatic resin composition except that it does not contain the bleeding effect agent is multiplied by c1. c2The antistatic resin composition according to the above item [4], wherein a 99% charge decay time γ1 (seconds) of the antistatic resin composition having an antistatic agent content of 0.75% by mass and a multiplier c2 of the charge decay time γ2 (seconds) of a control resin composition having the same composition as the antistatic resin composition except that it does not contain the bleed effect agent satisfy the relationship of the following formula (C2): 0.2≦c2-c1≦0.9 (C1) 5≦γ2-γ1≦10 (C2)

[0012] Furthermore, according to the present invention, there is provided the following antistatic resin molding. [8] An antistatic resin molded article, which is a molded product of the antistatic resin composition according to any one of [4] to [7] above. [9] The antistatic resin molding according to [8], which is an automobile part, a building material part, a machine part, an electric or electronic part, a furniture or home appliance part, a container, a packaging material, or a film. Effect of the Invention

[0013] According to the present invention, even when a polypropylene resin or a low-density polyethylene resin is used as a diluent resin, it is possible to provide an antistatic masterbatch which can produce a resin composition or a resin molded article having excellent antistatic properties in a short time until an effective antistatic effect is exhibited.

[0014] Furthermore, according to the present invention, it is possible to provide an antistatic resin composition and an antistatic resin molded product which are obtained by using the above-mentioned antistatic masterbatch and which have excellent antistatic properties and which take a short time to exhibit an effective antistatic effect. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] <Antistatic masterbatch> Hereinafter, an embodiment of the present invention will be described, but the present invention is not limited to the following embodiment. One embodiment of the antistatic masterbatch of the present invention contains at least one base resin selected from the group consisting of homopolypropylene resin, ethylene-propylene random copolymer, and low-density polyethylene resin, a donor-acceptor type antistatic agent, and a bleed effect agent. Hereinafter, the antistatic masterbatch of this embodiment (hereinafter also simply referred to as "masterbatch") will be described in detail.

[0016] (Base resin) The masterbatch of the present embodiment contains at least one base resin selected from the group consisting of a homopolypropylene resin, an ethylene-propylene random copolymer, and a low-density polyethylene resin.

[0017] From the viewpoint of manufacturing such as kneading, the content of the base resin in the masterbatch is preferably 60 to 94.5 mass %, and more preferably 70 to 90 mass %, based on the total mass of the masterbatch.

[0018] [Polypropylene resin] As the polypropylene resin, from the viewpoints of antistatic properties, processability, moldability, and the like, homopolypropylene resins such as crystalline homopolypropylene and ethylene-propylene random copolymers can be used.

[0019] Polypropylene resins can be classified according to their ethylene content. For example, a polypropylene resin having an ethylene content of 0 to 0.1% by mass is a crystalline homopolypropylene. A polypropylene resin having an ethylene content of more than 0.1% by mass and not more than 5% by mass is an ethylene-propylene random copolymer. The ethylene content of a polypropylene resin can be measured by infrared spectroscopy and 13 It can be measured by C-NMR measurement.

[0020] The MFR (melt flow rate) of the polypropylene resin measured according to the test method ISO1133 (230°C, 21.2N) is preferably 0.1 g / 10 min to 80 g / 10 min, and preferably 0.4 g / 10 min to 60 g / 10 min. If the MFR of the polypropylene resin is less than 0.1 g / 10 min, the viscosity is high, and the dispersibility of the antistatic agent and various additives may be slightly reduced. On the other hand, if the MFR of the polypropylene resin is more than 80 g / 10 min, the viscosity is low, and the dispersibility of the antistatic agent and various additives may be slightly reduced. These polypropylene resins are commercially available, for example, from Japan Polypropylene Corporation, SunAllomer Corporation, Prime Polymer Corporation, and the like.

[0021] [Low density polyethylene resin] The density of low-density polyethylene resin is usually 0.91 to 0.94 g / cm 3 The low-density polyethylene resin may be either a metallocene-based linear low-density polyethylene or a high-pressure low-density polyethylene.

[0022] The density of metallocene-based linear low-density polyethylene is 0.91 to 0.94 g / cm 3 It is preferable that the MFR of the metallocene-based linear low-density polyethylene is 2 to 16 g / 10 min. Examples of commercially available products of such metallocene-based linear low-density polyethylene include, under the trade names below, Sumikathene E (manufactured by Sumitomo Chemical Co., Ltd.), Harmolex (manufactured by Japan Polyethylene Co., Ltd.), and Elite (manufactured by Dow Chemical Co., Ltd.).

[0023] The density of high-pressure low-density polyethylene is 0.91 to 0.925 g / cm 3 It is preferable that the MFR of the high-pressure low-density polyethylene is 1 to 10 g / 10 min. Examples of commercially available products of such high-pressure low-density polyethylene include Novatec LD (manufactured by Japan Polyethylene Co., Ltd.), Suntec LD (manufactured by Asahi Kasei Corporation), Sumikathene (manufactured by Sumitomo Chemical Co., Ltd.), and Petrothene (manufactured by Tosoh Corporation), under the trade names below.

[0024] (Antistatic agent) A donor-acceptor type antistatic agent is, for example, a high molecular weight antistatic agent that has a donor part, which is a basic organic nitrogen compound that eliminates negative charges, and an acceptor part, which is a semi-polar organic boron compound that eliminates positive charges, in the molecule. When a donor-acceptor type antistatic agent is used, the charge generated by charge transfer transition is neutralized at the same time as the charge is generated, and the antistatic effect is expressed. On the other hand, low molecular weight antistatic agents usually have the effect of reducing the surface resistivity by bleeding out on the surface of a resin composition or a molded body, but they tend to last for a short period of time due to being scraped off from the surface by friction, etc.

[0025] The donor-acceptor type high molecular weight antistatic agent is less likely to bleed out on the surface of the resin composition or molded body, and the antistatic effect is expressed by being present near the surface. Therefore, when a donor-acceptor type high molecular weight antistatic agent is used, the surface resistivity of the resulting resin composition or molded body can be further reduced compared to when a low molecular weight antistatic agent is used, and it is also advantageous in terms of the charge decay rate. Furthermore, when a donor-acceptor type high molecular weight antistatic agent is used, the antistatic effect lasts for a longer period of time, and since it is less likely to bleed out, the surface condition of the resin composition or molded body can be maintained better. Other antistatic agents include, for example, ionic liquids. However, since ionic liquids are liquid at room temperature, when ionic liquids are used as antistatic agents, the moldability decreases and the impact strength of the resulting resin composition or molded body decreases. In addition, since ionic liquids can become solid depending on the temperature, the weather resistance of the resulting resin composition or molded body tends to decrease, and their uses tend to be limited.

[0026] The donor-acceptor type antistatic agent preferably contains a compound represented by the following formula (1): Furthermore, the donor-acceptor type antistatic agent is more preferably a compound represented by the following formula (1):

[0027] TIFF0007631603000002.tif58170 (In the general formula (1), R1 and R2 each independently represent R7COOCH2- or HOCH2-, and at least one of them is R7COOCH2-; R3 and R4 each independently represent CH3-, C2H5-, HOCH2-, HOC2H4-, or HOCH2CH(CH3)-; R5 represents -C2H4- or -C3H6-; and R6 and R7 each independently represent an alkyl group having 11 to 21 carbon atoms.)

[0028] In the general formula (1), R1 and R2 are preferably both R7COOCH2-. R3 and R4 are preferably each independently CH3- or C2H5-, more preferably both CH3-. R5 is preferably -C3H6-. The number of carbon atoms of the alkyl groups represented by R6 and R7 are preferably each independently 12 to 20, more preferably 14 to 18.

[0029] The content of the donor-acceptor type antistatic agent in the master batch is 5 to 25 mass % based on the total mass of the master batch, and preferably 10 to 20 mass %. If the content of the antistatic agent is less than 5 mass %, the amount of the antistatic agent present near the surface of the obtained resin composition or molded body is insufficient, resulting in insufficient antistatic effect. On the other hand, if the content of the antistatic agent is more than 25 mass %, the excess antistatic agent is likely to bleed out to the surface of the resin composition or molded body, and it becomes difficult to make the master batch.

[0030] (Bleeding effect agent) The bleeding effect agent is a component that has high affinity with the antistatic agent present in a dispersed state in the base resin, but has low compatibility with the base resin. effect By using this agent, the antistatic agent can be transferred to the vicinity of the surface of the resin composition or molded article obtained without excessive bleeding out onto the surface of the resin composition or molded article, while maintaining the surfaces of the resin composition or molded article in good condition.

[0031] In the master batch of this embodiment, the respective contents of the antistatic agent and the bleed effect agent and their quantitative ratio are appropriately set in consideration of the crystallinity and polarity of the polypropylene resin and the low-density polyethylene resin. The bleed effect agent acts both in a system in which the antistatic agent is relatively well dispersed in the resin and in a system in which the antistatic agent is difficult to disperse in the resin and tends to aggregate. Bleed effect The action of the bleed effect agent is considered to be related to the polarity, crystallinity, and density of the resin. As described above, it is effective when homopolypropylene resin, ethylene-propylene random copolymer, and low-density polyethylene resin are used as base resins or dilution resins. For example, it was confirmed that the bleed effect agent is effective when either homopolypropylene resin or ethylene-propylene random copolymer, which are polar resins with different crystallinity, is used. In addition, it was confirmed that the bleed effect agent is effective only when low-density polyethylene resin is used for low-density polyethylene resin and high-density polyethylene resin, which are non-polar resins with different crystallinity.

[0032] The bleeding effect agent is at least one selected from the group consisting of long-chain aliphatic alcohols, long-chain aliphatic esters, and surfactants. The long-chain aliphatic alcohol preferably has 12 or more carbon atoms. Among them, stearyl alcohol having 18 carbon atoms is preferred.

[0033] Examples of the surfactant include nonionic surfactants, anionic surfactants, and cationic surfactants. Examples of the nonionic surfactant include long-chain fatty acid esters, ethanolamines, and polyoxyethylene alkyl ethers. Examples of the anionic surfactant include alkyl sulfonates. Examples of the cationic surfactant include quaternary ammonium salts. Among these, it is preferable to use long-chain fatty acid esters and ethanolamines as the surfactant.

[0034] Examples of long-chain fatty acid esters include glycerin fatty acid esters, polyglycerin fatty acid esters, sorbitan fatty acid esters, polyoxysorbitan fatty acid esters, etc. Among these, it is preferable to use glycerin fatty acid esters.

[0035] The content of the bleed effect agent in the masterbatch is 0.5 to 15 mass% based on the total mass of the masterbatch, and preferably 1 to 10 mass%. If the content of the bleed effect agent is less than 0.5 mass%, the effect of transferring the antistatic agent to the surface of the molded body is reduced, resulting in insufficient antistatic effect. On the other hand, if the content of the bleed effect agent is more than 15 mass%, the effect of transferring the antistatic agent to the surface of the molded body is excessive, and the excess antistatic agent is likely to bleed out onto the surface of the resin composition or the molded body.

[0036] In the master batch, the amount of the bleed effect agent relative to 1 part by mass of the antistatic agent is 0.1 to 1 part by mass, preferably 0.15 to 0.5 parts by mass. If the amount of the bleed effect agent relative to 1 part by mass of the antistatic agent is less than 0.1 part by mass, the antistatic agent is less likely to migrate to the surface of the resin composition or molded article, and the time until the antistatic effect is exhibited cannot be shortened. On the other hand, if the amount of the bleed effect agent relative to 1 part by mass of the antistatic agent is more than 1 part by mass, the antistatic agent and the bleed effect agent are more likely to bleed out to the surface of the resin composition or molded article.

[0037] (Other Ingredients) The master batch may further contain other components in addition to the above-mentioned components, as necessary. Examples of other components include a flame retardant auxiliary, a filler for improving various properties such as mechanical properties, and other additives.

[0038] Examples of the flame retardant aid include metal hydroxides such as aluminum hydroxide, magnesium hydroxide, and calcium hydroxide. Examples of the filler include silica, talc, clay, mica, titanium oxide, glass beads, glass flakes, glass fibers, calcium carbonate, barium carbonate, calcium sulfate, barium sulfate, calcium silicate, potassium titanate, aluminum borate, magnesium borate, and carbon fibers. Examples of other additives include plasticizers, antioxidants, ultraviolet absorbers, light stabilizers, curing agents, curing accelerators, antistatic agents, conductivity-imparting agents, release agents, lubricants, dyes, and pigments.

[0039] (Method of manufacturing antistatic master batch) The master batch of this embodiment can be produced by mixing and melt-kneading a base resin, a donor-acceptor type antistatic agent, a bleed effect agent, and other components used as necessary. Specific examples of the melt-kneading method include a method in which each component is mixed in advance using various mixers such as a high-speed mixer, and then melt-kneaded using a kneading device such as a Banbury mixer, a roll, a plastograph, a single-screw extruder, a twin-screw extruder, and a kneader. Among them, from the viewpoint of production efficiency, it is preferable to melt-knead using an extruder, and it is more preferable to melt-knead using a twin-screw extruder. Each component is melt-kneaded using an extruder, and the resulting kneaded product is extruded into a strand shape, and then processed into a pellet shape, a flake shape, or the like.

[0040] The temperature during melt kneading may be, for example, 150 to 280°C, and can be appropriately set depending on the type of base resin used. When a polypropylene resin is used as the base resin, the temperature during melt kneading is preferably 180 to 270°C, more preferably 190 to 230°C. When a low-density polyethylene resin is used as the base resin, the temperature during melt kneading is preferably 160 to 250°C, more preferably 170 to 210°C. Since the master batch of this embodiment uses a donor-acceptor type antistatic agent, it is difficult to thermally decompose even when melt kneaded under such high temperature conditions, and the generation of an unpleasant odor can be avoided.

[0041] <Antistatic resin composition> The antistatic resin composition of this embodiment (hereinafter, also simply referred to as "resin composition") contains the above-mentioned antistatic master batch and at least one diluent resin selected from the group consisting of homopolypropylene resin, ethylene-propylene random copolymer, and low-density polyethylene resin. By making the resin composition contain the diluent resin to which antistatic properties are to be imparted and the master batch, the dispersibility of the antistatic agent is improved and the occurrence of poor appearance can be prevented compared to the case where each component is kneaded without using the master batch.

[0042] The resin composition of the present embodiment can be obtained by melt-kneading each component in the same manner as the masterbatch described above. The kneading device that can be used and the temperature during melt-kneading are the same as those used in the production of the masterbatch described above.

[0043] The resin composition is preferably in the form of pellets or flakes. The resin composition can be molded by various molding methods such as extrusion molding, injection molding, calendar molding, film molding, sheet molding, blow molding, injection blow molding, inflation molding, and foam molding to produce a molded article (antistatic molded article) of a desired shape. In particular, the resin composition of the present embodiment is suitable as a material for producing a resin molded article having a portion with a thickness of 100 μm or more.

[0044] (diluted resin) The diluent resin is a thermoplastic resin similar to the base resin used in the masterbatch. That is, the diluent resin is at least one thermoplastic resin selected from the group consisting of homopolypropylene resin, ethylene-propylene random copolymer, and low-density polyethylene resin. Since the diluent resin has good compatibility with the masterbatch, it is preferable that the diluent resin is the same type of thermoplastic resin as the base resin used in the masterbatch. The content of the masterbatch in the resin composition is preferably 1 to 20 mass % and more preferably 1 to 10 mass % based on the total amount of the resin composition.

[0045] The content of the thermoplastic resin in the resin composition (the total content of the base resin and the diluted resin) is preferably 92% by mass or more and 99.945% by mass or less based on the total mass of the resin composition. From the viewpoint of imparting antistatic properties to the diluted resin, the content of the antistatic agent in the resin composition is preferably 0.05% by mass or more and 5% by mass or less, and more preferably 0.05% by mass or more and 2.5% by mass or less, based on the total mass of the resin composition. The content of the bleed effect agent in the resin composition is preferably 0.005% by mass or more and 3% by mass or less, and more preferably 0.005% by mass or more and 1.5% by mass or less, based on the total mass of the resin composition.

[0046] (Surface resistivity) By using the above-mentioned master batch, antistatic properties can be easily imparted to the diluted resin, and the resin composition of this embodiment exhibiting the desired antistatic properties can be obtained. Specifically, when the base resin and the diluted resin are both homopolypropylene resins, the surface resistivity (10 a1 The surface resistivity (10 Ω / sq) of the control resin composition, which has the same composition as the resin composition except that it does not contain a bleeding effect agent, is a2 and a2, a multiplier of Ω / sq, preferably satisfy the relationship of the following formula (A1). 0.6≦a2-a1≦3 (A1)

[0047] In addition, when the base resin and the diluent resin are both ethylene-propylene random copolymers, the surface resistivity (10 b1 The surface resistivity (10 Ω / sq) of the control resin composition, which has the same composition as the resin composition except that it does not contain a bleeding effect agent, is b2 and a multiplier b2 of the linear exponent Ω / sq preferably satisfy the relationship of the following formula (B1). 0.3≦b2-b1≦1 (B1)

[0048] Furthermore, when the base resin and the diluent resin are both low-density polyethylene resins, the surface resistivity (10 c1 The surface resistivity (10 Ω / sq) of the control resin composition, which has the same composition as the resin composition except that it does not contain a bleeding effect agent, is multiplied by c1. c2 and a multiplier c2 of the linear exponent Ω / sq preferably satisfy the relationship of the following formula (C1). 0.2≦c2-c1≦0.9 (C1)

[0049] (charge decay time) By using the above-mentioned master batch, the resin composition of the present embodiment can be obtained with a short charge decay time and a shortened time until the antistatic effect is exerted. Specifically, when the base resin and the dilution resin are both homopolypropylene resins, the 99% charge decay time α1 (seconds) of the resin composition containing 0.75 mass% of the antistatic agent and the 99% charge decay time α2 (seconds) of the control resin composition having the same composition as the resin composition except that it does not contain the bleed effect agent preferably satisfy the relationship of the following formula (A2). 80≦α2-α1≦118 (A2)

[0050] Furthermore, when the base resin and the diluent resin are both ethylene-propylene random copolymers, the 99% charge decay time β1 (seconds) of a resin composition containing 0.75 mass% of an antistatic agent and the 99% charge decay time β2 (seconds) of a control resin composition having the same composition as the resin composition except that it does not contain a bleed effect agent preferably satisfy the relationship of the following formula (B2). 6≦β2-β1≦12 (B2)

[0051] Furthermore, when the base resin and the diluent resin are both low-density polyethylene resins, the 99% charge decay time γ1 (seconds) of a resin composition containing 0.75 mass% of an antistatic agent and the 99% charge decay time γ2 (seconds) of a control resin composition having the same composition as the resin composition except that it does not contain a bleed effect agent preferably satisfy the relationship of the following formula (C2). 5≦γ2-γ1≦10 (C2)

[0052] The resin composition of the present embodiment is useful as a resin material for producing various resin molded bodies (articles) that are excellent in design and charge decay because components such as antistatic agents and bleeding effect agents are less likely to bleed out and the surface condition is maintained in a good, non-sticky state.

[0053] (Antistatic resin molding) The antistatic resin molded body of this embodiment (hereinafter, also simply referred to as "resin molded body" or "molded body") is a molded product of the above-mentioned antistatic resin composition. Therefore, the resin molded body of this embodiment has a short charge decay time, shortens the time until an effective antistatic effect is exerted, and has excellent antistatic properties, even though it uses polypropylene resin or low-density polyethylene resin as a diluent resin. In addition, since it contains a donor-acceptor type antistatic agent, an excellent antistatic effect is exerted for a long period of time. Therefore, the resin molded body of this embodiment is useful as an automobile part, a building material part, a machine part, an electric / electronic part, a furniture / home appliance part, a container, a packaging material, or a film. EXAMPLES

[0054] The present invention will be described in detail below with reference to examples, but the present invention is not limited to these examples. In the examples and comparative examples, "parts" and "%" are by mass unless otherwise specified.

[0055] <Preparing materials> The following materials were prepared.

[0056] (Polypropylene resin) h-PP: Homopolypropylene resin, product name "Novatec PP-MA3", manufactured by Japan Polyethylene Corporation, MFR 11g / 10min r-PP: Ethylene-propylene random copolymer, product name "Prime Polypro F219DA", manufactured by Prime Polymer, MFR 8g / 10min

[0057] (Polyethylene resin) LDPE: Low density polyethylene resin, product name "Suntech LD F2270", manufactured by Asahi Kasei Chemicals Corporation, density 0.92g / cm 3 , MFR7g / 10min HDPE: High density polyethylene resin, product name "Hi-Zex 5305E", manufactured by Prime Polymer, density 0.95g / cm 3 , MFR 0.79g / 10min

[0058] (Antistatic agent) A donor-acceptor type antistatic agent (BN type charge transfer type antistatic agent) represented by the following formula (2):

[0059] TIFF0007631603000003.tif59170

[0060] (Bleeding effect agent) A-1: Stearyl alcohol: Trade name "Kalcol 8098", manufactured by Kao Chemical Co., Ltd. A-2: Glycerin fatty acid ester A: Product name "Dasper K200", manufactured by Miyoshi Oil Co., Ltd. A-3: Glycerin fatty acid ester B: Product name "Electrostripper TS-5", manufactured by Kao Chemical Co., Ltd.

[0061] <Masterbatch manufacturing> Example 1 A mixture was obtained by mixing 80 parts of h-PP, 15 parts of antistatic agent, and 5 parts of bleed effect agent A-1. The mixture was melt-kneaded at 170 to 210°C for 3 minutes using a lab mixer (product name "R60H type", manufactured by Toyo Seiki Seisakusho Co., Ltd.) to obtain a master batch.

[0062] (Examples 2 to 10, Comparative Examples 1 to 9, Reference Examples 1 to 4) A masterbatch was obtained in the same manner as in Example 1, except that the types and amounts (units: parts) of each component shown in Tables 1-1 and 1-2 were used. In Comparative Example 7, the strands became liquid, and a masterbatch could not be obtained.

[0063] <Production of resin composition and molded body (test piece)> The master batch was mixed with the same type of base resin as that used in the master batch so that the concentration of the antistatic agent was 0.75%, and then the mixture was melt-kneaded at 180 to 240°C using a single-screw extruder (product name "IPE-30", manufactured by CTE Corporation) to obtain a homogeneous resin composition. The resin composition obtained was injection molded using an injection molding machine (product name "SANJECT3601", manufactured by Yamashiro Seiki Co., Ltd.) under conditions of a cylinder temperature of 190 to 215°C and a mold temperature of 40°C to obtain a test piece (45mm x 60mm x 2mm) that was an injection molded body.

[0064] <Evaluation> (Measurement of surface resistivity) The surface resistivity of the obtained test piece was measured using a surface resistivity meter (Worksurface Tester ST-4, manufactured by Simco Japan) under the conditions of an applied voltage of 100 V and a measurement time of 30 seconds. n The multiplier (n) of 10 Ω / sq is shown in Tables 1-1 and 1-2. 13.5 Any value exceeding "10 Ω / sq" is 13.5 Ω / sq", so "10 13.5"Ω / sq" was set as the upper limit of the surface resistivity. In addition, in order to confirm the effect obtained by using the bleeding effect agent, the values ​​of "a2-a1", "b2-b1", and "c2-c1" were calculated for the resin compositions obtained in Examples 1 to 3, 9, and 10. The results are shown in Table 2.

[0065] (Measurement of charge decay time) The obtained test piece was conditioned for 24 hours (temperature 23±2°C, humidity 50±2%RH), and a charge decay meter (product name "STATIC HONESTMETER H-0110", manufactured by Shishido Co., Ltd.) was used to apply -10kV for 30 seconds, and then the charge amount was measured at 120 seconds. After the application was completed, the time until the applied voltage of -10kV was 1% or less (99% charge decay) (99% charge decay time) was measured. With this charge decay meter, all values ​​over "120 seconds" are "120 seconds", so "120 seconds" was set as the upper limit of the 99% charge decay time. In addition, in order to confirm the effect obtained by using the bleeding effect agent, the values ​​of "α2-α1", "β2-β1", and "γ2-γ1" were calculated for the resin compositions obtained in Examples 1 to 3, 9, and 10. The results are shown in Table 2.

[0066] (Bleed-out prevention) The produced test pieces were observed and evaluated for bleed-out inhibition according to the following evaluation criteria, and the results are shown in Tables 1-1 and 1-2. ○: No poor appearance or stickiness was observed. △: Poor appearance and stickiness were observed in some areas. ×: Poor appearance and stickiness were observed throughout.

[0067] TIFF0007631603000004.tif126170

[0068] TIFF0007631603000005.tif103170

[0069] TIFF0007631603000006.tif86170

[0070] (Application example: film production) Using a 20 mm single-screw extruder equipped with a T-die, the resin composition obtained in Example 1 was extrusion molded under the processing temperature condition of 170 to 210°C to prepare a film (test piece) having a thickness of about 50 μm. The film thus produced had the same performance as the test piece obtained by injection molding. [Industrial Applicability]

[0071] The antistatic masterbatch of the present invention is useful as a material for producing resin compositions and various molded articles having excellent antistatic properties.

Claims

1. The present invention comprises at least one base resin selected from the group consisting of homopolypropylene resin, ethylene-propylene random copolymer, and low-density polyethylene resin, a donor-acceptor type antistatic agent, and a bleed effect agent, the bleed effect agent is a long chain aliphatic alcohol; The content of the antistatic agent is 5 to 25% by mass, The content of the bleeding effect agent is 0.5 to 15% by mass, The amount of the bleed effect agent relative to 1 part by mass of the antistatic agent is 0.1 to 1 part by mass.

2. The antistatic masterbatch according to claim 1 , wherein the antistatic agent comprises a compound represented by the following general formula (1): (In the general formula (1), R １ and R ２ Each independently represents R ７ COOCH ２ - or HOCH ２ - and at least one is R ７ COOCH ２ - and R ３ and R ４ Each independently represents CH ３ -, C ２ H ５ - , HOCH ２ --HOC ２ H ４ - or HOCH ２ CH (CH ３ )-, R ５ is -C ２ H ４ -or-C ３ H ６ - indicates R ６ and R ７ each independently represents an alkyl group having 11 to 21 carbon atoms.

3. 2. The antistatic masterbatch according to claim 1, wherein the bleed effect agent is stearyl alcohol.

4. The antistatic masterbatch according to any one of claims 1 to 3, and at least one diluent resin selected from the group consisting of a homopolypropylene resin, an ethylene-propylene random copolymer, and a low-density polyethylene resin.

5. The base resin and the diluent resin are both homopolypropylene resins, The surface resistivity (10 ａ１ The surface resistivity (10 Ω / sq) of a control resin composition having the same composition as the antistatic resin composition except that it does not contain the bleeding effect agent is a multiplier a1. ａ２ and a multiplier a2 of the linear exponent Ω / sq satisfy the relationship of the following formula (A1), The 99% charge decay time α of the antistatic resin composition having an antistatic agent content of 0.75% by mass １ (seconds), and the 99% charge decay time α of a control resin composition having the same composition as the antistatic resin composition except that it does not contain the bleeding effect agent. ２ The antistatic resin composition according to claim 4, wherein (seconds) satisfies the following formula (A2): 0.6≦a2-a1≦3...(A1) 80≦α ２ -α １ ≦118 ・・・(A2)

6. The base resin and the diluent resin are both ethylene-propylene random copolymers, The surface resistivity (10 ｂ１ The surface resistivity (10 Ω / sq) of a control resin composition having the same composition as the antistatic resin composition except that it does not contain the bleeding effect agent is a multiplier b1. ｂ２ and a multiplier b2 of the square root of the square root of the sigma-squared constant Ω / sq satisfy the relationship of the following formula (B1), The 99% charge decay time β of the antistatic resin composition having an antistatic agent content of 0.75% by mass １ (seconds), and the 99% charge decay time β of a control resin composition having the same composition as the antistatic resin composition except that it does not contain the bleeding effect agent. ２ The antistatic resin composition according to claim 4, wherein (seconds) satisfies the following formula (B2): 0.3≦b2-b1≦1...(B1) 6≦β ２ -β １ ≦12 ・・・(B2)

7. The base resin and the diluent resin are both low-density polyethylene resins, The surface resistivity (10 ｃ１ The surface resistivity (10 Ω / sq) of a control resin composition having the same composition as the antistatic resin composition except that it does not contain the bleeding effect agent is a multiplier c1. ｃ２ and a multiplier c2 of the square root of the square root of the sigma-squared constant Ω / sq satisfy the relationship of the following formula (C1), The 99% charge decay time γ of the antistatic resin composition having an antistatic agent content of 0.75% by mass １ (seconds), and the 99% charge decay time γ of a control resin composition having the same composition as the antistatic resin composition except that it does not contain the bleeding effect agent. ２ The antistatic resin composition according to claim 4, wherein (seconds) satisfies the following formula (C2): 0.2≦c2-c1≦0.9...(C1) 5≦γ ２ -c １ ≦10 ・・・(C2)

8. 5. An antistatic resin molded article which is a molded product of the antistatic resin composition according to claim 4.

9. 9. The antistatic resin molding according to claim 8, which is an automobile part, a building material part, a machine part, an electric or electronic part, a furniture or home appliance part, a container, a packaging material, or a film.

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