Resin raw material composition for molding, resin raw material composition for microporous film, and methods for producing the same

Abstract

According to the present disclosure, a resin raw material composition containing resin pellets, powder and liquid components is provided. The resin raw material composition is a resin raw material composition for molding or a resin raw material composition for a microporous membrane. The resin raw material composition comprises: at least a portion of the surface of the above-mentioned resin pellets is covered with the above-mentioned liquid component, and the above-mentioned powder is attached to the liquid component. Taking the total mass of the resin raw material composition as a reference, the ratio of the mass % of the above-mentioned resin pellets to the mass % of the above-mentioned powder is greater than 0.01 and less than 100, and the ratio of the mass % of the above-mentioned resin pellets to the mass % of the above-mentioned liquid component is greater than 1 and less than 199. And taking the total number of granules as a reference, the number of granules including aggregates formed by more than 10 granules of the above-mentioned resin pellets is less than 20%.

Description

Technical Field

[0001] The present disclosure relates to a molding resin raw material composition, a microporous film resin raw material composition, and methods for producing the same. Background Art

[0002] Conventionally, general-purpose plastics such as polyethylene, process plastics such as polyester, synthetic resins such as elastomers, and especially polyolefin resins such as polyethylene and polypropylene have a good balance of molded product properties, molding processability, and weather resistance, and are widely used in packaging films, agricultural and other industrial films, blow molding of bottles and containers, structural materials, injection molding of large containers, and the manufacture of microporous films.

[0003] The pellets and powdered resin raw materials used in these applications are generally widely known to be formed by extrusion molding. These resin raw materials are used in the form of a single resin, or mixed with inorganic fillers, fiber materials, etc. other than the resin. In addition, in order to give functions to the resin raw materials, fillers are mixed, or liquid raw materials, such as plasticizers of mineral oils such as liquid paraffin, or antifogging agents, antistatic agents, etc. are added in liquid form, or mixed with glycerides. Extrusion molding of pellets is recorded in Patent Document 1, and extrusion molding of powders is recorded in Patent Document 2.

[0004] Most of these resin raw materials are usually sold in the form of pellets with a particle size of about 2 mm to 5 mm, and sometimes in the form of powders with a particle size of about 50 μm to 500 μm. In addition, metal oxides of aluminum oxide, silicon dioxide, zirconium oxide and titanium oxide, as well as fillers such as talc, boehmite and kaolin are usually sold in the form of powders of about 10 nm to 500 μm. Recently, as described in Patent Document 3, it is also possible to make a raw material by crushing and fragmenting a thin film or microporous membrane in a non-melting manner.

[0005] As a use of microporous membranes, the market for microporous membrane-shaped separators for lithium ion secondary batteries has been increasing, especially in electric vehicles. Patent Document 2 also discloses a method for producing such a separator for lithium ion secondary batteries.

[0006] In order to improve the functionality of molded products, there are more and more examples of mixing liquids with pellets and powders and molding them. As examples, there are separators for lithium-ion secondary batteries that are made porous by mixing plasticizers such as liquid paraffin with resin powders such as polyethylene and polypropylene, extruding and stretching, and then extracting the plasticizers with solvents. The usual technology is to add plasticizers such as mineral oil for softening to pellets of polyethylene, elastomers, and polypropylene.

[0007] In addition, ultra-high molecular weight polyethylene resin with a viscosity average molecular weight of more than 300,000 can obtain a molded product or microporous membrane with very high strength when molded, but on the other hand, due to the high molecular weight, the melt viscosity is significantly high, and it is difficult to extrude and mold, so it is usually not sold in the form of pellets, but in the form of polymer powder. When it is necessary to mix the ultra-high molecular weight polyethylene powder with ordinary polyethylene or polypropylene pellets and achieve high strength, it is necessary to mix the pellets and powder for use.

[0008] When utilizing these conventional techniques, pellets or powders are basically fed into an extruder alone, or mixed in advance as necessary, and then fed into an extruder. This method is widely and generally used.

[0009] Prior art literature

[0010] Patent Literature

[0011] Patent Document 1: Japanese Patent Application Laid-Open No. 59-39536

[0012] Patent Document 2: Japanese Patent Application Publication No. 2002-194132

[0013] Patent Document 3: Japanese Patent Application Publication No. 2006-21519

[0014] Patent Document 4: Japanese Patent Application Publication No. 2019-142002 Summary of the invention

[0015] Problem that the invention aims to solve

[0016] However, when using the prior art, especially when pellets and powders are mixed and simultaneously used for extrusion molding, especially film molding, and when pellets and powders are mixed and simultaneously extruded for the production of microporous membranes, there are problems with molding processability and product properties.

[0017] <Problems with formability>

[0018] In the manufacture of a resin raw material composition for molding, a method of mixing pellets and powders in advance in large quantities using a drum mixer, a Henschel mixer, etc. is generally adopted. When using this method, since a large amount of processing can be achieved, the production cost can be suppressed. At this time, first, during piping transportation, the pellets and powders are graded in a static hopper, and the composition distribution is prone to unevenness. The reason is that compared with pellets with a particle size of several mm, powders are usually small, ranging from several μm to hundreds of μm. Therefore, during piping transportation, the pellets and powders are graded in a static hopper, and the composition distribution is prone to unevenness. For example, if resin pellets of about 3 mm and inorganic fillers of about 5 μm or less are mixed in a weight ratio (resin pellets: inorganic fillers) of about 8:2, and filled into a hopper with a diameter of 500 mm, a height of 1000 mm, and a capacity of 100 liters, they are slowly graded during operation and the powder settles. As a countermeasure, even if an agitator is installed at various locations in the process, the problem cannot be fundamentally solved because the agitator will be reclassified very close to the downstream of the installation location. In addition, since the powder raw material is light, it is easy to fly in the air in the form of dust, which can easily deteriorate the working environment around the resin raw material supply port of the extruder (hereinafter sometimes referred to as "dust generation" etc.).

[0019] In the manufacture of microporous membrane resin raw material compositions such as separators, an extrusion molding method in which a single or multiple resin raw materials are mixed and put into an extruder is generally used. Extrusion molding is widely used in film forming, blow molding, fiber forming, injection molding, etc. because it is low-cost and easy to obtain a molded product. However, when pellets and fillers and resin powders are simultaneously put into an extruder, due to the difference in their sizes, classification is produced in the usual dry mixing, and the distribution of each raw material component is easily insufficient. Therefore, if directly put into an extruder, the dispersion and mixing in the extruder become uneven, and the variation of film thickness is easily produced due to the variation of the extrusion state. For example, for the film forming of the inflation method, adhesion preventing agents such as silicon dioxide and calcium carbonate for the opening of bubbles are used. However, this method also requires mixing pellets, silicon dioxide, calcium carbonate, etc. in advance, and the manufacturing cost increases.

[0020] In particular, for separators obtained by wet methods, which are now widely used as separators for lithium-ion secondary batteries, in order to swell the resin with a plasticizer, resin powders with small particle sizes are usually used as raw materials. However, examples of using pellet raw materials for various purposes have also increased recently. As the main raw material, commercially available polyolefins have more types or circulations of pellets than powders, so it is believed that the use of pellets for purposes such as cost reduction will increase in the future. In addition, if it is a pellet, various functional masterbatches, such as masterbatches containing lubricants, antistatic agents, and fillers, can be used together with pellets. In addition, the opportunities for global environmental protection have increased recently, and even for extrusion molding purposes, the recycling of raw materials has been promoted. For recycled raw materials, films and molded products are crushed and melt-granulated using an extruder. Therefore, in order to use recycled raw materials, it is necessary to use them in the form of pellets. It is expected that even in the use of separators, the necessity of using these pellet-shaped resin raw materials together with powders will also increase in the future.

[0021] One of the common methods of simultaneously feeding pellets and powder into an extruder and forming them with high quality is to optimize the screw shape of the extruder, or to lengthen the axial length of the screw and increase the time for mixing. These methods require large-scale and specialized equipment to increase the energy of mixing, and the manufacturing cost increases. In addition, since the particle diameters of powder and pellets are greatly different, classification occurs in the stage before being put into the extruder, such as in the feed hopper, and good shaping cannot be performed. When using the prior art in this way, when it is put into the extrusion mixing machine, it is impossible to obtain a raw material composition in which pellets and powders are not classified, and there is no method for mixing pellets and powders well.

[0022] More specifically, compared with pellets with a particle size of several mm, powders are usually small, ranging from several μm to hundreds of μm. Therefore, when transported by piping and placed in a static hopper, pellets and powders are classified, and the composition distribution is prone to unevenness. For example, if resin pellets of about 3 mm and inorganic fillers of about 5 μm or less are mixed at a weight ratio of about 8:2 (resin pellets: inorganic fillers) and filled into a hopper with a diameter of 500 mm, a height of 1000 mm, and an effective capacity of about 100 liters, they are slowly classified during operation and the powder settles. As a countermeasure, even if countermeasures such as setting up agitators at various locations in the process are adopted, they will be classified again very close to the downstream of the setting, so it cannot be fundamentally solved. In addition, since the powder raw material is light, it is easy to fly in the air in the form of dust, especially to deteriorate the working environment around the resin raw material supply port of the extruder (hereinafter sometimes recorded as "dust-raising").

[0023] 〈Product physical properties issues〉

[0024] If the composition distribution is uneven due to classification as described above, the film thickness is likely to change due to the change of the extrusion state as described above, so the obtained extruded products, such as films, and the obtained microporous films, such as separators, have the following tendency: fish eyes, unmelted gels, or uneven thickness variation within the film surface due to insufficient mixing, or uneven strength. Even if the composition distribution is eliminated to the allowable range, the melting rate (time until melting) in the extruder will be different due to the difference in the shape of the pellets and powder, especially the difference in their particle size, and the large pellets will be melted and residual, or on the contrary, the surface of the pellets will be dissolved in advance and entangled with the powder, and the mixing energy cannot be transferred to the powder. There are also examples of powder melting and residual. If this phenomenon occurs, it will also lead to changes in extrusion pressure and extrusion volume. In order to solve the above problem, if the necessary raw materials are melted and granulated in advance using a twin-screw mixer, etc., it will be improved, but the same phenomenon will occur when it is put into the twin-screw mixer, and it cannot be fundamentally solved. In addition, the number of manufacturing steps increases, the production cost increases significantly, and further, the thermal degradation and shearing caused by passing through a plurality of extruders increase the degradation, and there is a tendency for the overall strength to decrease.

[0025] Thus, in any of the above methods, there are problems with forming processability and / or product properties. When using the previous solution, not only the manufacturing cost increases, but also the combination range of applicable components is narrow due to the difference in the size of the pellets and the powder, the mixing amount, and the need for each fine adjustment of each component. These problems are particularly important for the microporous membrane of the separator for lithium ion secondary batteries, which has recently progressed in thin filmization.

[0026] In view of the above, the purpose of the present disclosure is to provide a resin raw material composition for molding, a resin raw material composition for microporous membranes, and a method for manufacturing the same, which have good dispersibility, piping transportability and formability, less dusting and classification, and can produce molded products or microporous membranes with various good physical properties.

[0027] Solutions for solving problems

[0028] The present inventors have conducted intensive studies to solve the above problems and have found that the above problems can be solved by using a resin raw material composition that satisfies specific conditions. They have also found a method for producing such a resin raw material composition.

[0029] Examples of embodiments of the present disclosure are listed below.

[0030] [1] A resin raw material composition comprising resin pellets (PL), powder (PW) and a liquid component (LQ),

[0031] The above-mentioned resin raw material composition is a molding resin raw material composition,

[0032] The resin raw material composition comprises: at least a part of the surface of the resin pellets is covered with the liquid component, the resin pellets covered with the liquid component are single particles or aggregates of a plurality of particles, and the powder is attached to the liquid component.

[0033] Based on the total mass of the resin raw material composition, the ratio of the mass % of the resin pellets to the mass % of the powder (PL / PW) is 0.01 or more and 100 or less, and the ratio of the mass % of the resin pellets to the mass % of the liquid component (PL / LQ) is 1 or more and 199 or less,

[0034] The number of granules including aggregates composed of 10 or more of the resin pellets is 20% or less based on the total number of granules.

[0035] [2] A resin raw material composition comprising resin pellets (PL), powder (PW) and a liquid component (LQ),

[0036] The above-mentioned resin raw material composition is a resin raw material composition for a microporous membrane,

[0037] The resin raw material composition comprises: at least a part of the surface of the resin pellets is covered with the liquid component, the resin pellets covered with the liquid component are single particles or aggregates of a plurality of particles, and the powder is attached to the liquid component.

[0038] Based on the total mass of the resin raw material composition, the ratio of the mass % of the resin pellets to the mass % of the powder (PL / PW) is 0.01 or more and 100 or less, and the ratio of the mass % of the resin pellets to the mass % of the liquid component (PL / LQ) is 1 or more and 199 or less,

[0039] The number of granules including aggregates composed of 10 or more of the resin pellets is 20% or less based on the total number of granules.

[0040] [3] The resin raw material composition according to item 1 or 2, which mainly comprises granules in which the powder is attached to the liquid component of the resin pellets covered with the liquid component.

[0041] [4] A resin raw material composition according to any one of items 1 to 3, wherein the number of granules comprising individual particles of the above-mentioned resin granules or aggregates of 2 to 9 particles is 95% or more based on the total number of granules, and the number of granules having a particle size of 10 mm or more is 1% by mass or less based on the total mass of the above-mentioned resin raw material composition.

[0042] [5] A resin raw material composition according to any one of items 1 to 4, wherein the number of granules comprising individual particles of the above-mentioned resin pellets is 70% or more based on the total number of granules, and the maximum diameter of the granules comprising individual particles of the above-mentioned resin pellets is greater than the particle size of the above-mentioned resin pellets and less than the particle size of the above-mentioned resin pellets + 5 mm.

[0043] [6] The resin raw material composition according to any one of items 1 to 5, wherein the number of granules comprising aggregates of a plurality of particles of the resin granules is less than 30% based on the total number of granules, and

[0044] When the resin raw material composition further includes granules composed of the powder and the liquid component without the resin pellets, the number of granules without the resin pellets is less than 20% based on the total number of granules.

[0045] [7] The resin raw material composition according to any one of items 1 to 6, wherein the number of granules including aggregates formed of 10 or more of the resin granules is 1% or less based on the total number of granules.

[0046] [8] The resin raw material composition according to any one of items 1 to 7, wherein the resin pellets contain at least one selected from the group consisting of polyolefins, PET, polyamide, aromatic polyamide, polyvinyl chloride, synthetic rubber, ABS and PPE.

[0047] [9] The resin raw material composition according to any one of items 1 to 8, wherein the powder contains at least one selected from the group consisting of polyethylene, elastomer, PET, polyamide, aromatic polyamide and inorganic particles.

[0048]

[10] The resin raw material composition according to any one of items 1 to 9, wherein the particle size of the powder is 10 nm or more and 50 μm or less.

[0049]

[11] The resin raw material composition according to any one of items 1 to 10, wherein the liquid component is at least one selected from the group consisting of lubricating oil, mineral oil and liquid paraffin.

[0050]

[12] The resin raw material composition according to any one of items 1 to 11, wherein the dispersion of bulk density of the resin raw material composition is 10% or less.

[0051]

[13] The resin raw material composition according to any one of items 1 to 12, wherein the angle of repose of the resin raw material composition is 30° or more and 55° or less.

[0052]

[14] A method for producing a resin raw material composition, wherein:

[0053] The above-mentioned resin raw material composition is a molding resin raw material composition,

[0054] The method for producing the resin raw material composition comprises:

[0055] a covering step of kneading the resin pellets and the liquid component by a mixer, thereby covering at least a portion of the surface of the resin pellets with the liquid component; and

[0056] The attachment step is a step of adding powder to the mixer after the covering step and further kneading the powder to attach the powder to the liquid component of the resin pellets covered with the liquid component.

[0057]

[15] The method for producing a resin raw material composition according to item 14, wherein the torque rise time is within 150 seconds.

[0058]

[16] A method for producing a resin raw material composition, wherein:

[0059] The above-mentioned resin raw material composition is a resin raw material composition for a microporous membrane,

[0060] The method for producing the resin raw material composition comprises:

[0061] a covering step of kneading the resin pellets and the liquid component by a mixer, thereby covering at least a portion of the surface of the resin pellets with the liquid component; and

[0062] The attachment step is a step of adding powder to the mixer after the covering step and further kneading the powder to attach the powder to the liquid component of the resin pellets covered with the liquid component.

[0063]

[17] The method for producing a resin raw material composition according to item 16, wherein the torque rise time is within 150 seconds.

[0064]

[18] A method for producing a mixed composition, comprising:

[0065] A step of producing a resin raw material composition using the method for producing a resin raw material composition according to item 16 or 17; and

[0066] A step of further mixing resin pellets (PL) and / or powder (PW) which are the same as or different from the resin pellets (PL) and the powder (PW) with the resin raw material composition.

[0067] Effects of the Invention

[0068] According to the present disclosure, when being used for film and microporous membrane, it is provided that various excellent physical properties such as strength, optics, foreign matter are obtained in the forming process, and the forming resin raw material composition with excellent formability and operability is obtained. In addition, according to the present disclosure, it is also provided to obtain a microporous membrane with excellent various physical properties and a microporous membrane resin raw material composition with excellent formability and operability. Therefore, the forming resin raw material composition disclosed in the present disclosure is particularly well used for the forming of film and microporous membrane. BRIEF DESCRIPTION OF THE DRAWINGS

[0069] Figure 1 This is a photograph of granules of the resin raw material composition of the present disclosure.

[0070] Figure 2 This is a photograph of granular bodies of a conventional resin raw material composition.

[0071] Figure 3 It is a graph showing the relationship between the kneading time and the average torque (torque rise time) of the resin raw material composition of Example 1.1 and the resin raw material composition of Comparative Example 1.1. DETAILED DESCRIPTION

[0072] 《Resin raw material composition》

[0073] The resin raw material composition disclosed in the present invention contains pellets, powder and liquid components (hereinafter sometimes recorded as "PL", "PW" and "LQ" respectively). The resin raw material composition is a resin raw material composition for molding or a resin raw material composition for a microporous membrane. The resin raw material composition contains a lot of granules, which contain aggregates having one pellet or multiple pellets, the surface of all or part of the pellets is covered with a liquid, and then the liquid is attached with powdered granules (hereinafter, sometimes recorded as "PWL" in the specification of this application). In the specification of this application, granules having one (single particle) resin pellet are sometimes recorded as "PWL1", and granules having aggregates of multiple resin pellets are recorded as "PWL2", "PWL3"... etc. based on the number of resin pellets. Granules that do not contain resin pellets, are formed by powder and liquid components, and have a sieve diameter of 1 mm or more and 10 mm or less are sometimes recorded as "PWL0". “The total number of granules” refers to the total number of granules above PWL0 and PWL1.

[0074] The resin raw material composition preferably contains pellets, powders and liquid components as main components. Here, the "main component" means that the total mass of the pellets, powders and liquid components is 50% by mass or more, preferably 70% by mass or more, more preferably 90% by mass or more, and may be substantially 100% by mass relative to the total mass of the resin raw material composition. In addition to the main component, the resin raw material composition may also contain other additives, modifiers and other components as described below.

[0075] 〈Resin pellets〉

[0076] As resin pellets (PL), it is possible to use commonly used commercially available resin pellets. Any resin of the resin pellets can be used, for example, selected from polyolefins, polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polyacrylonitrile (PAN), polyamide, aromatic polyamide, polyvinyl chloride, synthetic rubber, acrylonitrile-butadiene-styrene copolymer resin (ABS), and polyphenylene benzobisoxazole (PPE). The material of the resin pellets is preferably selected from at least one of the groups consisting of polyolefins, PET, polyamide, aromatic polyamide, polyvinyl chloride, synthetic rubber, ABS and PPE. The resin pellets preferably contain polyolefins as the main component. "Main component" refers to 50% by mass or more, preferably 70% by mass or more, more preferably 90% by mass or more, and can also be substantially 100% by mass relative to the total mass of the resin pellets. As polyolefins, polypropylene (PP), polyethylene (PE) and olefin elastomers can be listed.

[0077] The polypropylene is not particularly limited, and examples thereof include homopolymers of propylene such as isotactic polypropylene (IPP), syndiotactic polypropylene, and atactic polypropylene; random copolymers (RPP), block copolymers (BPP), and terpolymers obtained by copolymerizing propylene with comonomers such as ethylene, butene, and α-olefins having more than 5 carbon atoms, etc. These may be either single substances or mixtures.

[0078] The viscosity average molecular weight (Mv) of the resin as the resin pellets is preferably 1,000,000 or less, more preferably 700,000 or less, and further preferably 600,000 or less, because melt kneading becomes easy, and as a result, when the resin raw material composition is formed into a film or a microporous membrane, there is a tendency to improve the fish-eye defect, so it is preferably 1,000,000 or less, more preferably 700,000 or less, and further preferably 600,000 or less. In addition, from the viewpoint of strength, the viscosity average molecular weight of the resin of the resin pellets is 100,000 or more, and more preferably 200,000 or more. In the case where the resin pellets are polypropylene, from the same viewpoint, the viscosity average molecular weight (Mv) of the polypropylene is preferably 1,000,000 or less, more preferably 700,000 or less, and further preferably 600,000 or less, and preferably 100,000 or more, and more preferably 200,000 or more.

[0079] Here, fisheye refers to small spherical blocks generated in film-like or sheet-like molded products or microporous membranes as defined in "Polymer Dictionary" written by Polymer Editorial Committee (Polymer Editing Committee), Daseisha, 1997, 6th edition, 337 pages, etc., and is named as such because most of them show transparency like fisheyes. Fisheyes are distinguished by the main causes of their generation, and various types of fisheyes can be listed, such as unmelted blocks caused by insufficient mixing of molding materials, blocks formed by gelation of part of the raw materials, blocks caused by partial deterioration of the materials during molding, and fisheyes with foreign matter as the core. However, in this specification, fisheyes are caused by the material of the resin raw material composition used as the raw material of the molded product, and fisheyes with foreign matter as the core are excluded. It should be noted that such foreign matter can be listed, for example, cellulose, dust, metal pieces, carbide of resin, different types of plastics, waste yarn, and paper pieces.

[0080] The resin of the resin pellet is preferably a polypropylene whose stereoregularity is controlled by a metallocene catalyst, or a resin obtained by mixing 0.5 to 30% by mass of BPP or RPP with respect to IPP. By using such a polypropylene, for example, in microporous membrane applications, permeability tends to be improved.

[0081] The resin of the resin pellets can be a mixture of polyethylene and polypropylene. As polyethylene, for example, high-density polyethylene, ultra-high molecular weight polyethylene, linear low-density polyethylene, high-pressure low-density polyethylene, and mixtures thereof can be cited. In addition, polyethylene with a narrow molecular weight distribution obtained by metallocene catalysts, high-density polyethylene, or polyethylene obtained by multi-stage polymerization can also be used. Among the above, from the viewpoint of reducing the heat shrinkage when forming a film or a microporous membrane, linear high-density polyethylene, ultra-high molecular weight polyethylene, or mixtures thereof obtained by ion polymerization are preferably used. The ultra-high molecular weight polyethylene referred to herein refers to polyethylene with a viscosity-average molecular weight of more than 500,000. As the ratio of ultra-high molecular weight polyethylene to all polyethylene, it is preferably 5 to 50% by mass, and from the viewpoint of dispersibility, it is more preferably 9 to 40% by mass. However, at this time, ultra-high molecular weight polyethylene is usually used in powder form, so it is classified as "powder" at this time.

[0082] Polyethylene preferably contains a polyethylene component with a molecular weight less than 10,000. The polyethylene component with a molecular weight less than 10,000 referred to herein refers to a portion of the molecular weight less than 10,000 in a graph of molecular weight distribution measured by gel permeation chromatography (GPC), and its ratio can be obtained by the area ratio on the graph. If a polyethylene component with a molecular weight less than 10,000 is formed under specific conditions, a portion of it moves to the surface of the microporous membrane, and as a result, it has the effect of reducing the amount of polypropylene on the surface. As a method for making such a polyethylene component with a molecular weight less than 10,000 contained in polyethylene, it can be prepared by setting polymerization conditions in a manner containing a lot of low molecular weight components during the polymerization of polyethylene, or it can be prepared by mixing a polyethylene component with a weight average molecular weight less than 10,000 in a common polyethylene.

[0083] The content of the polyethylene component with a molecular weight less than 10,000 is preferably 5% by mass or more relative to the total polyethylene amount. If it is within this range, friction is reduced in the film-making of the film and microporous membrane, and there is a tendency to improve productivity. More preferably, it is 10% by mass or more. If it is within this range, there is a tendency to improve the winding processability in the secondary processing steps of these films and microporous membranes. And then if it is 20% by mass or more, further high-speed processing can be achieved, and there is a tendency to improve productivity. On the other hand, from the viewpoint of improving the strength of the film and microporous membrane, it is preferably 50% by mass or less. In addition, from the viewpoint of further improving friction reduction, it is preferably more than 1% by mass of the polyethylene component with a molecular weight less than 1000.

[0084] The resin of the resin pellets may contain polybutene-1 resin, propylene elastomer, ethylene elastomer, and especially random copolymer elastomer of propylene and ethylene, as a resin other than polypropylene and polyethylene, in order to improve film forming properties. Polymethylpentene-1 resin may also be used, and a resin having a melt flow rate (MFR) of 0.01 to 30 g / 10 minutes is preferably used. It is particularly preferably in the range of 0.1 to 5 g / 10 minutes.

[0085] The resin of the resin pellets may be, in addition to the above, an engineering plastic resin such as polyphenylene ether, a polyamide resin such as nylon 6, nylon 6-12, and aramid resin, a polyimide resin, a polyester resin such as PET and PBT, a polycarbonate resin, a fluorine resin such as polyvinylidene fluoride (PVDF), a copolymer of ethylene and vinyl alcohol, a copolymer of C2 to C12 α-olefin and carbon monoxide and its hydride, a hydride of a styrene polymer, a copolymer of styrene and α-olefin and its hydride, a copolymer of styrene and aliphatic monounsaturated fatty acid, an acrylic acid and acrylic acid derivative polymer, a copolymer of styrene and a conjugated diene unsaturated monomer and their hydrides, and the like.

[0086] From the viewpoint of extrusion molding properties, the particle size of the resin pellets is preferably in the range of about 1 mm to 10 mm, more preferably 2 mm to 6 mm, and further preferably 3 mm to 5 mm. The method for producing the pellets is not limited. For example, in the case of high-density polyethylene, polyethylene powder having a particle size of tens to hundreds of μm polymerized by a low-pressure method is melt-kneaded in an extruder heated to about 200° C., and then cut into a particle size of about 1 mm to 5 mm by wire cutting or underwater cutting. Pellets obtained by cutting a film temporarily formed by pressure bonding can also be used.

[0087] The proportion of the resin pellets in the total mass of the resin raw material composition is preferably 5% by mass to 98% by mass, more preferably 30% by mass to 98% by mass.

[0088] <powder>

[0089] Powder (PW) refers to fine particles with a particle size of several nm to several hundred μm. The ratio of powder to the total mass of the resin raw material composition is preferably 5% to 90% by mass, and more preferably 8% to 50% by mass. The powder is preferably resin particles, inorganic particles, etc., and may also be powder obtained by crushing fibers, natural powders such as wood chips, fine metal particles, etc.

[0090] The resin particles can be, for example, the resins listed as the above-mentioned resin pellets. The type and molecular weight of the resin are described in the column of the resin pellets, so they are omitted here. As a method for preparing the resin pellets, there can be listed a method of pulverizing a polymerized resin or its pellets.

[0091] As resin particles, among the resins listed as resin pellets, powders of polyethylene, polypropylene, elastomer, PET, polyamide, and aramid, etc. can be listed. The resin particles preferably contain polyolefin as a main component. "Main component" means that the total mass of the resin pellets is 50% by mass or more, preferably 70% by mass or more, more preferably 90% by mass or more, and can also be substantially 100% by mass. As polyolefin, polyethylene, polypropylene, and olefin-based elastomers are preferably listed, and polyethylene is more preferred.

[0092] As the viscosity average molecular weight (Mv) of the resin particles, from the viewpoint of improving the strength of the film and microporous membrane, it is preferably 200,000 or more, and more preferably 300,000 or more. As the upper limit of the viscosity average molecular weight (Mv), from the viewpoint of extrusion formability and stretchability, it is preferably 10 million or less, and more preferably 5 million or less. As the viscosity average molecular weight (Mv) of the polyethylene powder (the overall viscosity average molecular weight when using a variety of polyethylenes), from the viewpoint of improving the strength of the film and microporous membrane, it is preferably 200,000 or more, and more preferably 300,000 or more. As the upper limit of the viscosity average molecular weight (Mv), from the viewpoint of extrusion formability and stretchability, it is preferably 10 million or less, and more preferably 5 million or less. From the viewpoint of improving the mixing property of inorganic fillers and the like and suppressing the defects of the granular state formed by the secondary aggregation of inorganic fillers, the molecular weight distribution (Mw / Mn) of the polyethylene powder is preferably 5 or more, and more preferably 8 or more. As described above, from the viewpoint of reducing the thermal shrinkage when forming a film or microporous membrane, a powder of ultra-high molecular weight polyethylene can be used.

[0093] The diameter of the resin particles is smaller than the size of the pellets, and the average diameter is preferably 300 μm or less. If it is 300 μm or less, the reaction time is shortened during the production of the polymerized powder, and the productivity is excellent. The diameter of the resin particles is preferably 200 μm or less, and more preferably 100 μm or less. The lower limit is not particularly limited, and is appropriately prepared from the viewpoint of dust explosion during air transportation during molding, and can be, for example, 10 μm or more, 50 μm or more, or 100 μm or more.

[0094] The proportion of the resin particles in the total mass of the resin raw material composition is preferably 5% by mass to 90% by mass, more preferably 10% by mass to 50% by mass.

[0095] As inorganic particles, for example, oxide ceramics such as aluminum oxide (such as α-alumina, etc.), silicon dioxide, titanium dioxide, zirconium oxide (containing yttria-modified zirconium oxide), magnesium oxide, cerium oxide, yttria, zinc oxide, and iron oxide can be listed; nitride ceramics such as silicon nitride, titanium nitride, and boron nitride; ceramics such as silicon carbide, calcium carbonate, aluminum sulfate, aluminum hydroxide, potassium titanate, talc, kaolin clay, kaolinite (kaolin), halloysite, pyrophyllite, montmorillonite, sericite, mica, magnesium chlorite, bentonite, asbestos, zeolite, calcium silicate, magnesium silicate, diatomaceous earth, and silica sand; glass fiber, etc., which can be used alone or in combination. Among them, as inorganic particles, at least one selected from the group consisting of silicon dioxide, aluminum oxide, zeolite, kaolin, talc, zirconium oxide, and titanium dioxide is preferred.

[0096] The proportion of the inorganic particles in the total mass of the resin raw material composition is preferably 3% by mass to 90% by mass, more preferably 5% by mass to 55% by mass.

[0097] The particle size of the inorganic particles is not particularly limited, and is, for example, not less than 10 nm and not more than 50 μm. In addition, various particle sizes can be used as needed. For example, in the case of using hydrophobic inorganic particles to improve wettability with organic solvents, in order to improve dispersibility and surface area in the resin, inorganic particles with a relatively small average particle size, such as 5 nm to 1 μm, preferably about 5 nm to 100 nm, can be used. On the other hand, if inorganic particles with an average particle size of 1 μm to 10 μm are used, there is a tendency to improve the strength of the thin film and microporous membrane, and further, if inorganic particles with an average particle size of 1.5 μm to 5 μm are used, there is a tendency to improve the uneven thickness during film formation. The bulk specific gravity (bulk density) of the inorganic particles is 0.05 g / cm 3 ~10g / cm 3 About 0.1 to 5 g / cm 3 These powders may be used alone or in combination.

[0098] 〈Liquid ingredients〉

[0099] By containing a liquid component in the resin raw material composition, the pellets and the powder are integrated, and the dusting caused by the powder can be suppressed. If the liquid component (LQ) is liquid and can suppress dusting, it is not particularly limited. It is preferably a lubricating oil or mineral oil used as a plasticizer in the manufacture of molded products and microporous membranes. It can be phthalates such as dioctyl phthalate (DOP) and dibutyl phthalate (DBP) that contribute to the performance of the product obtained by extrusion molding, liquid paraffin, other plasticizers, softeners and antifogging agents. The liquid component (LQ) is preferably selected from at least one of the groups consisting of lubricating oil, mineral oil and liquid paraffin. It should be noted that when the molded product is used for microporous membranes, plasticizers such as liquid paraffin are mostly or completely removed from the final product. Through the action of the liquid component, powders that are usually easy to classify with pellets and have the characteristics of flying in the workplace in the form of dust, such as nanofillers with a particle size of about 5nm to 50nm, can also be used well.

[0100] The viscosity of the liquid component is not particularly limited. When a resin powder having a relatively large particle size, for example, 100 μm or larger, is used, a relatively high viscosity is preferred, and a kinematic viscosity (JIS K 2283) at 40° C. of 50 mm 2 / S or more, more preferably 60mm 2 / S or more. If the viscosity is high, the adhesion to the pellets is good, and the pellets and powder are not easily separated during transportation.

[0101] The ratio of the liquid component to the total mass of the resin raw material composition is preferably 0.1% by mass to 30% by mass, more preferably 2% by mass to 7% by mass.

[0102] 〈Granular Body〉

[0103] The granules are formed by covering at least a portion of the surface of the resin pellets with a liquid component, the resin pellets covered with the liquid component are in the form of individual particles or aggregates of a plurality of particles, and powder is attached to the liquid component. And the number of granules (PWL10 or more) including aggregates formed of 10 or more resin pellets is 20% or less based on the total number of granules. By reducing the number of PWL10 or more, a resin raw material composition with less classification, excellent dispersibility, piping transportability, moldability, and various physical properties obtained can be provided.

[0104] In order to obtain such a resin raw material composition with a small number of PWL10 or more, the weight mixing ratio of PL, LQ and PW is preferably appropriate. First, the mass % ratio of the resin pellets to the mass % of the powder (PL / PW) is preferably about 99.01 / 0.99 (upper limit) to 1 / 99 (0.01 to 100), more preferably 99 / 1 (upper limit) to 1 / 99 (0.01 to 99), further preferably 95 / 5 (upper limit) to 10 / 90 (0.11 to 19), further preferably 95 / 5 (upper limit) to 50 / 50 (1 to 19), particularly preferably 95 / 5 (upper limit) to 66.7 / 33.3 (2 to 19), particularly preferably 90 / 10 (upper limit) to 70 / 30 (2.3 to 9). For example, PL / PW is preferably 2 or more and 100 or less. In the range exceeding the upper limit, the adhesiveness of the resin raw material composition increases, and there is a tendency to be difficult to transport by piping. If the value is less than the lower limit, the adhesion between the pellets and the powder is insufficient, and classification is likely to occur, which tends to generate dust due to the powder.

[0105] In addition, the mass % of the resin pellets relative to the mass % of the liquid component (PL / LQ) is an upper limit of 99.5 / 0.5 to a lower limit of 50 / 50 (1 to 199), preferably an upper limit of 99 / 1 to a lower limit of 50 / 50 (1 to 99), more preferably an upper limit of 99 / 1 to a lower limit of 70 / 30 (2.3 to 99), further preferably an upper limit of 98 / 2 to a lower limit of 70 / 30 (2.3 to 49), and further preferably an upper limit of 97 / 3 to a lower limit of 80 / 20 (4 to 32.3). Within this range, the dispersibility is stable. If the upper limit is exceeded, PL is difficult to be covered by LQ, and dust and classification are easily generated. If it is less than the lower limit, LQ is excessive, stickiness is generated, and there is a tendency for the piping transportability to deteriorate.

[0106] The ratio of the mass % of the powder to the mass % of the liquid component (PW / LQ) is preferably within the range of an upper limit of 99 / 1 to a lower limit of 20 / 80 (0.25 to 99), more preferably an upper limit of 95 / 5 to a lower limit of 30 / 70 (0.43 to 19), and further preferably an upper limit of 90 / 10 to a lower limit of 40 / 60 (0.67 to 9). If the mixture is mixed at a mixing ratio within this range and kneaded using appropriate means such as a drum mixer or a Henschel mixer, the outer surface of the pellets is covered with the liquid component, and the powder is easily attached to the resin pellets. By being 0.25 or more, the adhesion of the powder is improved, and by being 99 or less, the stickiness of the resin raw material composition caused by the liquid component is suppressed, and there is a tendency for the pipe transportability to be improved.

[0107] In the resin raw material composition, the maximum diameter of the granules (PWL1) of the individual particles containing the resin pellets is preferably equal to or larger than the particle diameter of the resin pellets, more preferably larger than the particle diameter of the resin pellets, preferably equal to or smaller than the particle diameter of the resin pellets + 5 mm, more preferably equal to or smaller than the particle diameter of the resin pellets + 4 mm, further preferably equal to or smaller than the particle diameter of the resin pellets + 3 mm, further preferably equal to or smaller than the particle diameter of the resin pellets + 2 mm, further preferably equal to or smaller than the particle diameter of the resin pellets + 1 mm. If the maximum diameter of the granules (PWL1) of the individual particles containing the resin pellets is within the above range, the number of granules with excess powder attached to the surface of the resin pellets is reduced, classification can be further suppressed, and there is a tendency that the pipe transportability is further improved.

[0108] The resin raw material composition preferably has a granular body in which a powder is attached to the liquid component of the resin pellets covered with the liquid component as a main component. Here, the "main component" means that the granular body accounts for 50% by mass or more, preferably 70% by mass or more, more preferably 90% by mass or more, and may be substantially 100% by mass relative to the total mass of the resin raw material composition.

[0109] From the viewpoints of operability, low dusting and formability, the number of single-particle granules (PWL1) and 2-9 granules (PWL2-9) is preferably 95% or more based on the total number of granules; and the number of granules with a particle size of 10 mm or more is preferably 1% by mass or less based on the total mass of the resin raw material composition. From the same viewpoint, the number of granules of resin pellets containing multiple particles is preferably less than 30%, more preferably less than 20%, based on the total number of granules; and when the resin raw material composition also contains granules (PWL0) formed of powder and liquid components without resin pellets, the number of PWL0 is preferably less than 20%, more preferably less than 10%, based on the total number of granules. PWL0 refers to granules with a sieve size of 1 mm or more and 10 mm or less. If there are many blocks with a size of less than 1 mm or more than 10 mm, the dispersion state will deteriorate. From the same viewpoint, the number of granules (PWL10 or more) containing 10 or more resin granules based on the total number of granules is 20% or less, preferably 1% or less, and more preferably substantially no granules are contained.

[0110] It is particularly preferred that the number of PWL1 is 70% or more based on the total number of granules, and the maximum diameter of the granules (PWL1) containing individual particles of the resin pellets is not less than the particle diameter of the resin pellets and not more than the particle diameter of the resin pellets + 5 mm. By making the number of PWL1 not less than a certain ratio and reducing its maximum diameter, a resin raw material composition having particularly excellent handling properties, low dust generation properties, and moldability can be obtained.

[0111] 〈Bulk density〉

[0112] The bulk density of the resin raw material composition is largely determined by its specific gravity, especially when an inorganic filler is used. For use as a normal raw material, it is preferably 0.1 g / cm 3 ~2g / cm 3 , more preferably 0.3 g / cm 3 ~1.5g / cm 3 , more preferably 0.5 g / cm 3 ~1.2g / cm 3 In addition, the deviation of bulk density is preferably 10% or less, more preferably 5% or less, and further preferably 3% or less. If the bulk density and its deviation are within the above range, the supply amount to the extruder is stabilized, and the uniformity of the film product or microporous membrane is improved.

[0113] 〈Angle of repose〉

[0114] The resin raw material composition preferably has an angle of repose of 30° or more and 55° or less. When the angle of repose is within the above range, it can be used favorably using a raw material hopper or a supply feeder of a common extrusion molding device.

[0115] 〈Torque rise time〉

[0116] The resin raw material composition preferably has a torque rise time of less than 150 seconds using a Plastomill mixer (manufactured by Toyo Seiki Co., Ltd.). In the present application specification, "torque rise time" refers to the time from the start of mixing until the torque of the Plastomill mixer rises and reaches a peak soon. A short torque rise time means that the resin pellets and the liquid component in step (a) are fully mixed and the liquid component can be roughly uniformly attached to the surface of the resin pellets. As a result, it is easy to obtain a structure that is stable as PWL1 with a maximum diameter of less than the particle size of the resin pellets + 5 mm.

[0117] 〈Other ingredients〉

[0118] The resin raw material composition may contain, in addition to pellets, powders and liquid components, other resin components other than these forms, inorganic fillers, antioxidants, dispersing aids, antistatic agents, processing stabilizers, crystal nucleating agents and other additives, organic fillers and other additives, etc., for the purpose of modification, cost reduction, etc. The proportion of each of these components in the resin raw material composition is preferably 5% by mass or less, more preferably 2% by mass or less, and may be substantially 0% by mass.

[0119] As antioxidants, phenolic antioxidants such as "Irganox 1010", "Irganox 1076", and "BHT" (all trademarks, manufactured by Ciba Specialty Chemicals Inc.) can be listed; phosphorus-based and sulfur-based secondary antioxidants; and hindered amine-based weathering agents, etc., which can be used alone or in combination as needed. In particular, a combination of a phenolic antioxidant and a phosphorus-based antioxidant is suitably used. Specifically, pentaerythritol-tetrakis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], octadecyl-3-(3,5-di-tert-butylhydroxyphenyl)propionate, 1,3,5-trimethyl-2,4,6-tris(3,5-di-tert-butylhydroxybenzyl)benzene, tris(2,4-di-tert-butylphenyl)phosphite, tetrakis(2,4-di-tert-butylphenyl)-4,4'-biphenylenephosphite, etc. are preferred. In addition, 6-[3-(3-tert-butyl-4-hydroxy-5-methylphenyl) propoxy]-2,4,8,10-tetra-tert-butyl dibenzo[d,f][1,3,2]dioxyphosphatine and the like are also suitable. The amount of the antioxidant blended is preferably 100 ppm to 10000 ppm relative to the total mass of the resin pellets of the resin raw material composition. When a phenolic antioxidant and a phosphorus antioxidant are used in combination, the mass ratio of the phenolic antioxidant to the phosphorus antioxidant is preferably 1 / 3 to 3 / 1.

[0120] In the case where the resin raw material composition is used for the forming of a microporous film, in particular, in the case of manufacturing a microporous film by extrusion molding, the resin raw material composition preferably contains a resin pellet of polypropylene as a resin pellet, and contains a crystal nucleating agent in order to control the crystallinity of the polypropylene and control the formation of microporous. As the type of crystal nucleating agent, it is not particularly limited, and the carboxylic acid metal salts such as the common benzyl sorbitol system (" GEL ALL " (trademark New Japan Chemical Society system)), phosphate metal salts, aluminum tert-butyl benzoate, etc. can be listed. As its specific example, it is bis (p-ethyl benzyl) sorbitol, bis (4-methyl benzyl) sorbitol, bis (3,4-dimethyl benzyl) sorbitol, bis benzyl sorbitol, etc. As the compounding amount of the crystal nucleating agent, although it depends on the desired crystallization conditions, from the viewpoint that crystallization is rapidly carried out and formability becomes easy, it is preferably more than 100ppm relative to the amount of polypropylene, and from the viewpoint of preventing excessive oozing caused by excessive crystal nucleating agent, it is preferably less than 10000ppm. The more preferred amount of the crystal nucleating agent is 100 ppm to 2000 ppm relative to the polypropylene. In the manufacture of a conventional microporous membrane using a plasticizer, when liquid paraffin or a phthalate-based plasticizer is used, a microporous membrane using polyethylene is easy to exhibit permeability, while polypropylene has smaller pores than polyethylene and tends to have poor permeability. As a means of improving the permeability of the polypropylene, a method of adjusting the pores to an appropriate size is effective, for example, by using a crystal nucleating agent, adjusting the phase separation rate, and facilitating the formation of an appropriate pore structure.

[0121] In addition, as the dispersing aid for polypropylene and polyethylene, for example, hydrogenated styrene-butadiene elastomers, elastomers copolymerized with ethylene and propylene, etc. can also be used as needed. The blending amount of these dispersing aids is not particularly limited, but is preferably 1 to 10 parts by weight relative to 100 parts by weight of the total amount of polypropylene and polyethylene.

[0122] As antistatic agents, amines such as alkyldiethanolamine and hydroxyalkylethanolamine, amine esters such as stearyldiethanolamine monofatty acid esters, alkanolamides such as lauric acid diethanolamide and stearic acid diethanolamide, glycerol, monofatty acid esters of diglycerol, anionic antistatic agents such as alkylbenzenesulfonic acid, and polyoxyethylene alkyl ethers can be listed, and they can be used alone or in combination. The amount of the antistatic agent is not particularly limited, but is preferably about 500 to 10,000 ppm relative to the total mass of the resin pellets of the resin raw material composition.

[0123] 《Mixed composition containing resin raw material composition》

[0124] In the case where the resin raw material composition disclosed in the present invention is a resin raw material composition for microporous membrane, the resin raw material composition for microporous membrane, which can be used alone for the formation of microporous membrane, can also be used for the formation of microporous membrane in the form of a mixed composition mixed with pellets (PL) and / or powder (PW). That is, the resin raw material composition for microporous membrane disclosed in the present invention can be used as a masterbatch to manufacture a desired mixed composition. The additional mixed PL and / or PW can be the same material as the PL and PW contained in the resin raw material composition for microporous membrane, or it can be a different material. For example, polypropylene pellets can be used as PL, polyethylene powder can be used as PW, and mineral oil can be used as LQ, for example, a microporous membrane resin raw material composition (raw material A) of PL / PW / LQ=85 / 10 / 5 (weight mixing ratio) is manufactured, and a polyethylene powder (raw material B) that is the same or different from the polyethylene powder used in raw material A is further added and mixed therein to obtain a mixed composition. At this time, since PW is already attached to PL of raw material A, there is an advantage that the mixed composition is not easily classified when dry-mixed with PW of raw material B. According to this method, the desired composition can be adjusted by a simple method such as dry mixing, so the productivity can be greatly improved.

[0125] 《Method for producing resin raw material composition》

[0126] The method for producing a resin raw material composition disclosed herein comprises the following steps (a) and (b) when the resin raw material composition is a molding resin raw material composition.

[0127] (a) The coating step is to knead the resin pellets and the liquid component by a mixer, thereby coating at least a portion of the surface of the resin pellets with the liquid component.

[0128] (b) Adhering step: After the covering step, the powder is put into a mixer and further kneaded to adhere the powder to the liquid component of the resin pellets covered with the liquid component.

[0129] Each component can be added at once or divided into several additions. In addition, additives other than the above components can also be added through the steps (a) and / or (b). The addition of granules and powders can be appropriately added not only through (a) but also through (b). The mixers referred to in steps (a) and (b) are preferably mixers such as drum mixers and Henschel mixers. They can be used at room temperature. If a drum mixer is used in step (b), after mixing, a lot of powder and granules are attached to the inside of the mixer due to the liquid component. The raw material in the central part without attachment can be used directly, or the attachment can be scraped off with a scraper, etc., and then continued to mix and mix with the raw material in the central part. The same is true when a Henschel mixer is used in step (b). It should be noted that the method for producing a resin raw material composition for a microporous membrane can remove large particle size blocks using a sieve with an opening diameter of about 10 mm after any one of the processes in steps (a) and (b), preferably after step (b).

[0130] The method for producing a resin raw material composition disclosed herein includes the following steps (a') and (b') when the resin raw material composition is a resin raw material composition for a microporous membrane.

[0131] (a′) A coating step of mixing the resin pellets and the liquid component using a mixer to coat at least a portion of the surface of the resin pellets with the liquid component.

[0132] (b') Adhering step: After the covering step, the powder is put into a mixer and further mixed to adhere the powder to the liquid component of the resin pellets covered with the liquid component.

[0133] Each component can be added at once or divided into several additions. Additives other than the above components can also be added through the steps (a') and / or (b'). The addition of granules and powders can be appropriately added not only through (a') but also through (b'). The mixers referred to in the steps (a') and (b') are preferably mixers such as drum mixers and Henschel mixers. They can be used at room temperature. If a drum mixer is used in the step (b'), after mixing, a lot of powder and granules are attached to the inside of the mixer due to the liquid components. The raw material in the central part without attachment can be used directly, or the attachment can be scraped off with a scraper, etc., and then continued to mix and mix with the raw material in the central part. The same is true when a Henschel mixer is used in the step (b'). It should be noted that the method for producing a resin raw material composition for a microporous membrane can remove large particle size blocks using a sieve with an opening diameter of about 10 mm after any one of the processes in the steps (a') and (b'), preferably after the step (b').

[0134] In the method for producing the resin raw material composition disclosed in the present invention, in order to obtain a stable PWL1 having a maximum diameter equal to or less than the particle diameter of the resin pellets + 5 mm, it is preferred that the weight mixing ratio of PL, LQ and PW is appropriate. The weight mixing ratio is described in the column of "granular body", so it is omitted here.

[0135] The obtained resin raw material composition preferably has a torque rise time of 150 seconds or less by Plastomill. The details of the torque rise time are as described above, so the description is omitted here.

[0136] An example of a method for producing a resin raw material composition is described. As step (a), resin pellets and a liquid component are put into a mixer and kneaded. Thus, the surface of the resin pellets is appropriately wetted with the liquid component. It is preferred that the entire surface of the resin pellets is evenly covered with the liquid component. Then, as step (b), powder is added to the mixer and further stirred. Separate mixers can be used in step (a) and step (b), or powder can be added to the same mixer containing the resin pellets covered with the liquid component obtained in step (a) to perform step (b). Through step (b), powder is attached to the liquid component on the surface of the resin pellets, and the resin raw material composition of the present disclosure can be obtained. The granular body of the obtained resin raw material composition preferably has a maximum diameter of PWL1 of the particle size of the resin pellets + 5 mm or less, and is a stable structure as PWL1. Then, the resin raw material composition is put into any molding device, such as the hopper of an extruder. The resin raw material composition of the present disclosure has excellent operability and low dust properties due to less classification in the hopper and less dust generation. In addition, the pellets and powder are integrated, so it is not easy to separate the two. If the mixing is started in the drum just below the hopper of the extruder, each material is quickly and evenly dispersed and melted. Therefore, the resin raw material composition disclosed in the present invention also has excellent moldability.

[0137] As an example of steps (a) and (b), the following describes the case where a commercially available polyethylene pellet (PL1) is mixed with a commercially available anti-blocking agent (PW1) in the form of a powder and a mineral oil (LQ1) as a liquid component. As step (a), first weigh 20 kg of PL1, add LQ1 thereto, and stir for 10 minutes using an 80-liter drum mixer. Thus, the surface of PL1 is properly wetted with LQ1. Step (b): Then add PW1 and stir for further 5 minutes. The amount of input can be adjusted so that the composition ratio (wt%) after mixing is, for example, PL1 / PW1 / LQ1=92 / 5 / 3. The resin raw material composition thus manufactured can be supplied to a sieve with an aperture of about 10 mm to remove large particles.

[0138] Figure 1This is an example of a granular body of the resin raw material composition (10) disclosed in the present invention. In this example, the granular body contains only one granular body (PWL1 granule) as the main component. The resin raw material composition may also contain granular bodies having multiple granules of PWL2 to 10, but in a relatively small amount. In addition, it is confirmed that there is almost no granular body or powder dust formed only by powder and liquid components or substantially no granular body or powder dust. Therefore, the handleability, low dusting property and formability are excellent.

[0139] An example of a conventional method for manufacturing a resin raw material composition is described. In this method, first, resin pellets and powder are put into a mixer and kneaded, and then a liquid component is put into a mixer and kneaded. Therefore, the surface of the resin pellets cannot be uniformly covered with the liquid component as a whole, and the resulting resin raw material composition includes large granules formed by the liquid component and the powder, and large granules formed by gathering a large amount of powder around the resin pellets. It is speculated that this is because before the liquid component is uniformly attached to the surface of the resin pellets, the liquid component is attached to the part with more powder and the wall of the mixer, and large blocks of powder grow on the wall of the mixer, which are broken and formed. Then, if the resin raw material composition is put into the hopper of the extruder, it is easy to produce classification and deteriorate operability. Even if the drum directly below the hopper of the extruder is mixed, each material is not easy to be evenly dispersed and melted, so the former resin raw material composition has poor formability.

[0140] Another example of a conventional method for producing a resin raw material composition is described. In this method, resin pellets and powder are put into a mixer at once to produce a dry-mixed resin raw material composition. The obtained resin raw material composition is then put into the hopper of an extruder, but classification is easily generated, the operability is poor, and powder dust is generated.

[0141] An example of a method for producing a conventional microporous film resin raw material composition is described. In this method, a raw material composition formed by dry mixing only a plurality of powders is generally used. However, in the wet method, there is no example of mixing powder and granules for use. Therefore, in order to use the powder and granules simultaneously by the wet method, the granules and powder are put into a mixer (mixer) such as a Henschel mixer and dry mixed. However, the difference between the particle sizes of the powder and the granules is large and easy to classify. In order to reduce this classification, it is considered to add a liquid component thereto, but the liquid component integrates a plurality of resin granules and a large amount of powder. As a result, the obtained microporous film resin raw material composition includes a large granular body formed by the liquid component and the powder, and a large granular body formed by gathering a large amount of powder around the resin granules. It is speculated that this is because before the liquid component is evenly attached to the surface of the resin granules, the liquid component is attached to the part with more powder and the wall of the mixer, and on the wall of the mixer, a large block of powder grows and is broken and formed. Then, if the microporous film resin raw material composition is put into the hopper of the extruder, classification is easy to occur, and the operability is poor. Even if it is put into the extruder and kneading is started, each material is not easy to be evenly dispersed and melted, so fish eyes are often generated, and the moldability of the previous microporous film resin raw material composition is poor.

[0142] Other examples of the method for producing a conventional microporous film resin raw material composition are described. In this method, resin pellets and powder are put into a mixer at once to produce a dry-mixed microporous film resin raw material composition. The obtained microporous film resin raw material composition is then put into the hopper of an extruder, but classification is easily generated, operability is poor, and powder dust is generated.

[0143] Figure 2 This is an example of a granular body of a conventional resin raw material composition (30) produced by the above-mentioned dry blending method. In this example, since the sizes of the resin granules and the powder dust are different, classification is easily generated. In addition, since a large amount of powder dust is contained, it is known that the dust generation property is high.

[0144] 《Method for producing mixed composition》

[0145] It is also possible to further mix powder and / or granules in the resin raw material composition for microporous membrane of the present disclosure produced in steps (a') and (b') and use it in the form of a mixed composition (hereinafter referred to as step (c')). Step (c') can be carried out using a common mixer such as a Henschel mixer and a drum mixer. In step (c'), powder and / or granules can be added to the mixer used in step (b') after step (b'), or a mixer different from step (b') can be used.

[0146] Example

[0147] 《Measurement and evaluation methods》

[0148] <Contents (mass %) of PL, PW, and LQ in the resin raw material composition, and the ratio of PW to L>

[0149] The determination was performed by the following steps.

[0150] 1. The number of PWL0, PWL1, PWL2 and PWL10 and above, and the ratio of PWL1 to 9

[0151] 5 g of the resin raw material composition was sampled into a container (about 250 to 500 pellets). The number of PWL0, 1, 2, and 10 or more was counted and the respective ratios (number %) were calculated. In addition, the total weight of PWL1 to 9 was measured and the ratio (mass %) relative to the total weight (5 g) was measured.

[0152] 2. Determination of the ratio (mass %) of PL, PW and LQ

[0153] Collect 100 grains of PWL1 and measure the weight (W T ). It is washed with a solvent that dissolves only the liquid component (such as dichloromethane when the liquid component is liquid paraffin), PL and PW are filtered, and their weights (W PL+PW ). T -W PL+PW Calculate the weight of LQ (W LQ ) and weight ratio (mass %). Then PL and PW were sieved and their respective weights (W PL , W PW ), and weight ratio (mass %).

[0154] 3. Determination of the ratio (mass %) of particles with a particle size of 10 mm or more

[0155] 50 g of the resin raw material composition was sampled into a container (about 2500 to 5000 particles), and classified by a sieve with a pore size of 10 mm. The weight of particles with a particle size of 10 mm or more was measured, and the ratio (mass %) to the total weight (50 g) was determined.

[0156] 〈Particle size〉

[0157] For powders, pellets, and granules with a size of about 0.05 mm (50 μm) or more, the particle size was measured using a microscopic camera manufactured by KEYENCE CORPORATION, and for materials with a size below 0.05 mm, the particle size was measured using a scanning electron microscope. The diameter (maximum diameter) of the circle circumscribed with the particle to be measured was set as the particle size, and 100 particles were randomly selected to obtain the average.

[0158] 〈Dispersion (torque rise time)〉

[0159] The measurement was performed by the following procedure using a Plastomill R-60 manufactured by Toyo Seiki Co., Ltd. with a roller diameter of 30 mm.

[0160] step

[0161] 1. Prepare a resin raw material composition and liquid paraffin. The amount of liquid paraffin is adjusted to 30% by mass after the two are mixed, and mix them in a cup using a stirring rod. The total amount of the two is 48 g.

[0162] 2. A Plastomill manufactured by Toyo Seiki Co., Ltd. was set in an air atmosphere at a temperature of 200° C. and a rotation speed of 30 rpm.

[0163] 3. Quickly add the resin raw material composition prepared in step 1 and immediately start kneading. The time when the raw material addition is completed is set as 0 minutes.

[0164] 4. The time until the kneading torque of the Plastomill rises and reaches a peak soon after is measured.

[0165] This determination method is an index of the ease (dispersibility) of mixing in an actual extruder. In conventional extrusion molding, the resin raw material needs to start melting in the extruder in a short time and the screw torque needs to increase. If the torque rises slowly, the mixing capacity of the extruder cannot be fully utilized, resulting in poor dispersion.

[0166] The dispersibility was evaluated by the torque rise time according to the following criteria.

[0167] A150 seconds or less

[0168] B More than 150 seconds and less than 200 seconds

[0169] CMore than 200 seconds and less than 300 seconds

[0170] D More than 300 seconds

[0171] 〈Deviation of Bulk Density〉

[0172] Measured by the following method according to JIS-Z2504. 20 kg of the resin raw material composition disclosed in the present invention is put into a raw material hopper with a height of 600 mm, a diameter of 400 mm at the top, a diameter of 250 mm at the bottom, a hemispherical dome at the bottom, and an opening for extracting raw materials from the bottom of the dome. Just after the input, the resin is extracted 5 times from the upper surface of the raw material using a 200cc cup, and the first bulk density is calculated from the average weight. Then 15 g of raw material is extracted from the opening at the bottom of the hopper, and then the second bulk density is calculated using the same method. At this time, the ratio of the bulk density (1st bulk density / 2nd bulk density) is set as the deviation of the bulk density. Evaluate as follows.

[0173] The ratio of A bulk density is in the range of 0.95 to 1.05.

[0174] The ratio of the B bulk density is in the range of more than 0.90 and less than 0.95, or more than 1.05 and 1.10 or less.

[0175] The ratio of C bulk density is less than 0.90 or exceeds 1.10.

[0176] 〈Grading〉

[0177] Take 200g of the resin raw material composition disclosed by the sample and randomly put it into a cylindrical polyethylene sample bottle with an outer shape of 79mm and a capacity of 500cc. Vibrate it for 5 minutes using a commercially available small vibrator (KENIS LIMITED, KENIS MINISHAKER 3D33180556, oscillation amplitude of about 7 degrees, oscillation number 30rpm). Then collect 10g of the resin raw material composition from the upper part of the bottle (about 1 / 10 of the range by height) and the bottom of the bottle (about 1 / 10 of the range by height), count the number of pellets therein, and measure the number ratio (upper part / bottom part). In the case of good gradability, the number ratio is close to 1.0. Evaluate as described below.

[0178] The A number ratio is greater than or equal to 0.9 and less than 1.1.

[0179] The B number ratio is in the range of 0.85 or more and less than 0.9, or in the range of more than 1.1 and 1.15 or less.

[0180] The C number ratio is less than 0.85 or greater than 1.15.

[0181] 〈Angle of repose〉

[0182] Determine using a device based on JIS9301-2-2. Feed 200g of sample at a speed of 20g to 60g per minute from a height of about 40mm from the upper edge of the funnel. At this time, the falling speed is kept constant. Feed 200g of sample from the funnel, and measure the angle formed by the inclined surface formed by the sample and the horizontal plane using a protractor. Evaluate as described below.

[0183] The angle A is within the range of not less than 30° and not more than 55°.

[0184] B Angle is less than 30° or more than 55°.

[0185] 〈Dust generation (dust generation)〉

[0186] 500cc of the resin raw material composition was placed in a measuring cup and dropped from a height of 30cm onto a rectangular black paper with one side of 30cm or more. The dust flying was observed visually from the front and side 5 seconds after the drop to make a judgment. It should be noted that a black board was placed in the background so that the flying was easy to see. The evaluation was based on the following criteria.

[0187] ANo flying at all or even if flying, the height is less than 15cm.

[0188] B dance occurs at a height of more than 15cm.

[0189] 〈Pipeline transport performance〉

[0190] 5 kg of the resin raw material composition to be measured was prepared and transported to a height of 2 m using an air transport automatic loader connected to a 10 m long polyvinyl chloride hose. The ratio of bulk density before and after transport (before transport / after transport) was measured in the same manner as the above-mentioned <Bulk Density> measurement method.

[0191] The ratio of A bulk density is in the range of 0.95 to 1.05.

[0192] The ratio of the B bulk density is in the range of more than 0.90 and less than 0.95, or more than 1.05 and 1.10 or less.

[0193] The ratio of C bulk density is less than 0.90 or exceeds 1.10.

[0194] <Fish eyes of molding resin raw material composition>

[0195] The molding resin raw material composition is put into a twin-screw extruder with an axis diameter of 30mm and L / D35, kneaded at a specified temperature (230°C), extruded using a 300mm T-die, and cooled using a casting roll to obtain a non-stretched original roll with a thickness of 1mm. The original roll is cut into 8mm×8mm and stretched to 4 times×4 times using an intermittent biaxial stretching machine to form a film. The stretched film is cut into 20cm×20cm, and the fisheyes with a diameter of more than 0.5mm are counted. It should be noted that the evaluation is converted to a value per 10g of film.

[0196] AThe number of fish eyes is less than 5 / 10g

[0197] B The number of fish eyes is 6 to 20 / 10g

[0198] C The number of fish eyes exceeds 20 / 10g.

[0199] <Fish eyes of the resin raw material composition for microporous membrane>

[0200] Liquid paraffin as a plasticizer is further added and mixed into the resin raw material composition for microporous membrane containing liquid paraffin as a plasticizer, and the raw material adjusted in such a way that the amount of liquid paraffin forms 65% by weight after mixing is put into a twin-screw extruder with an axis diameter of 30 mm and L / D35, kneaded at a specified temperature (230°C), extruded using a 300mm T-die, and cooled using a casting roll to obtain an unstretched original roll with a thickness of 0.5 mm. The original roll is cut into 8mm×8mm and stretched to 7 times×7 times by an intermittent biaxial stretching machine for filming. The stretched film is then immersed in an excess of dichloromethane and dried, and the plasticizer is extracted and removed to obtain a microporous membrane. The obtained microporous membrane is cut into 20cm×20cm, and fisheyes with a diameter of 0.5mm or more are counted. It should be noted that the evaluation is converted to a value per 10g of microporous membrane.

[0201] AThe number of fish eyes is less than 5 / 10g

[0202] B The number of fish eyes is 6 to 20 / 10g

[0203] C The number of fish eyes exceeds 20 / 10g.

[0204] <Thickness of microporous membrane (μm)>

[0205] The thickness of the sample was measured at an ambient temperature of 23±2° C. using a micro thickness gauge manufactured by Toyo Seiki (type KBN, terminal diameter Φ5 mm, measuring pressure 62.47 kPa).

[0206] <Porosity of microporous membrane (%)>

[0207] The weight per unit area W (g / cm 2 ) and the average density ρ (g / cm 3 ), and calculated from the thickness d (cm) of the microporous membrane using the following formula.

[0208] Porosity = (W / (d×ρ))×100(%)

[0209] It should be noted that the porosity ratio of each layer (porosity of layer A / porosity of layer B) is

[0210] For example, if a three-layer film of A layer / B layer / A layer can be peeled off, peel it off and use the above method to determine it. In the case of the wet method, it may not be peeled off. In this case, the volume concentration P of the added solvent of each layer is measured (the A layer is set to P A , B layer is set to P B ), the thickness D obtained by cross-sectional observation using SEM (the thickness of the A layer is set to D A, the thickness of layer B is set to D B ), and the porosity of layer A is set to V A The porosity of layer B is V B , can be found by solving the following two equations together.

[0211] Formula 1: Total layer porosity = (P A ×D A ×Number of layers 2+P B ×D B × Number of layers1) / Total layer thickness

[0212] Formula 2…(V A / V B )=(P A / P B )

[0213] 〈Air permeability of microporous membrane (sec / 100cc)〉

[0214] The air permeability was measured using a Gurley air permeometer "G-B2" (manufactured by Toyo Seiki Seisaku-sho, Ltd., trademark) in accordance with JIS P-8117. The values ​​in the table are air permeabilities calculated by ratio calculation based on the total thickness at 20 μm.

[0215] <Puncture strength of microporous membrane (g)>

[0216] The value was determined by performing a puncture test using a portable compression tester "KES-G5" (trademark, manufactured by KATO TECH CO., LTD.) under the conditions of a curvature radius of the needle tip of 0.5 mm and a puncture speed of 2 mm / sec.

[0217] 《Examples 1.1 to 1.18》

[0218] The pellets, powders and liquids in Tables 1, 2 and 3 were used in the combination shown in Table 4 to prepare a molding resin raw material composition by the following steps.

[0219] (a) A predetermined amount of pellets was added to an 80-liter drum mixer, and a liquid component was added thereto, the liquid component being added to the center so as to prevent it from adhering to the mixer wall as much as possible. The mixture was then stirred for 10 minutes.

[0220] (b) Then, a predetermined amount of powder was added, and the mixture was further stirred for 10 minutes. PL / PW / LQ was added in a total amount of 20 kg according to the composition ratios shown in Tables 4 and 5.

[0221] In Examples 1.1 to 1.18, there was no stickiness, and the number of granules including aggregates formed of 10 or more resin pellets was less than 20%. The dispersibility, pipe transportability, gradability and dust generation properties of the molding resin raw material composition were all good. The deviation (gradability) of bulk density, angle of repose and fisheye were also all good.

[0222] Figure 3 The solid line shows the torque rise time in Example 1.1. The average torque peaked in about 100 seconds from the addition of the raw materials (start of kneading), which shows that the dispersibility is better than that of Comparative Example 1.1 (about 180 seconds).

[0223] 《Comparative Examples 1.1 to 1.5》

[0224] For Comparative Example 1.1, LQ was not added, and the powder and pellets were made into a molding resin raw material composition by dry mixing with the same composition as Example 1.4. Due to the absence of LQ, the powder and pellets were completely separated, and dust was also flying during transportation and classification in the hopper. For the manufacturing method of Comparative Example 1.2, although it was based on the same method as Example 1.1, it was a composition outside the scope of the present disclosure, so the performance was insufficient. Figure 3 The dotted line represents the torque rise time in Comparative Example 1.2. It takes about 180 seconds from the time the raw materials are dropped (mixing starts) for the average torque to reach the peak, and it can be seen that the dispersibility is worse than that of Example 1.1 (about 100 seconds). Comparative Examples 1.3 and 1.4 are the same methods as Example 1.1 except for the composition. For Comparative Example 1.5, although it has the same composition as Example 1.4, all the raw materials are added at once in step a and stirred for 20 minutes, and step b is not performed. In Comparative Example 1.3, the adhesion between the powder and the granules is insufficient, resulting in classification and dust. In Comparative Example 1.4, there are too many liquid components and they are adhesive. Therefore, a large number of PWL10 particles and PWL0 particles are produced. In Comparative Example 1.5, since all the raw materials of the granules, powders, and liquid components are stirred at once, no single particles are produced and all are PWL10 or above. As a result, the dispersibility and piping transportability are significantly deteriorated.

[0225] [Table 1]

[0226] Table 1. Pellets

[0227]

[0228] LDPE: Low-density polyethylene (viscosity average molecular weight 70,000)

[0229] HDPE1: High-density polyethylene (viscosity average molecular weight 200,000)

[0230] PP: Polypropylene (viscosity average molecular weight 950,000)

[0231] EL: Elastomer (viscosity average molecular weight 60,000)

[0232] [Table 2]

[0233] Table 2. Powders

[0234] PW1 HDPE2 Average particle size 200μm, Mv 2 million PW2 Packing 1 Primary particle size 13nm, dry silica PW3 Packing 2 Average particle size 3μm, talc

[0235] [Table 3]

[0236] Table 3. Liquid ingredients

[0237] LQ1 <![CDATA[Liquid paraffin, kinematic viscosity 68mm 2 / s (cst)]]>

[0238] [Table 4]

[0239]

[0240] [Table 5]

[0241]

[0242] 《Examples 2.1 to 2.22》

[0243] The pellets, powders (resin powders, fillers) and liquids in Tables 6, 7 and 8 were used in combination in Tables 9 and 10 to prepare a microporous film resin raw material composition by the following steps.

[0244] Step (a'): A predetermined amount of pellets was added to a tumble mixer, and a liquid component was added thereto, the liquid component being added to the center so as to prevent it from adhering to the mixer wall as much as possible. The mixture was then stirred at 15 rpm for 10 minutes.

[0245] Step (b'): Then add a prescribed amount of powder and stir for further 10 minutes. It should be noted that PL / PW / LQ is put into the composition ratio of Tables 9 and 10 in a total amount of 20 kg. If the lid of the mixer is temporarily opened here, many particles will adhere to the wall of the mixer, but if it is dropped into the mixer using a scraper or the like and further stirred for 5 minutes, a uniform microporous membrane resin raw material composition is obtained as a whole. The dispersibility, piping transportability, gradability and dust generation of the microporous membrane resin raw material composition are all good. The deviation (gradability) of the bulk density, the angle of repose and the fisheye are all good. The results are shown in Tables 9 and 10.

[0246] In Examples 2.1, 2.2, and 2.4 to 2.10, the microporous membrane resin raw material composition described in Tables 9 and 10 was used as it is. In Examples 2.3 and 2.11 to 2.22, after obtaining the microporous membrane resin raw material composition described in Tables 9 and 10, as step (c'), the powders described in Tables 11 and 12 were additionally added and mixed to obtain a mixed composition. Even in step (c'), good mixing was possible.

[0247] The prepared microporous membrane resin raw material composition or mixed composition was fed into a twin-screw extruder with a screw diameter of 44 mm. For Examples 2.3 and 2.11 to 2.22, the pellets were all covered with powder, so even when additional powder was added in step (c') and fed into the twin-screw extruder, there was no classification and a good mixing state was maintained.

[0248] Liquid paraffin as a plasticizer is added from the middle of the barrel of the extruder. The polymer content during extrusion after adding liquid paraffin is calculated by the following formula: {total mass of resin components (g) / total mass of the composition after liquid paraffin is added (g)}×100 (mass%), and is prepared in a manner of forming 33 mass%. Extrusion is performed at an extrusion temperature of 200°C, and the sheet-like molten resin extruded from the T-die head at the front end of the extruder is guided to a casting roll with a roller temperature of 90 degrees, and cooled and solidified to obtain an unstretched original roll of a specified thickness. The unstretched original roll is then guided to a biaxial stretching machine, and biaxially stretched at a temperature of 120°C at 7 times in the longitudinal direction and 7 times in the transverse direction, and then the plasticizer is removed by dichloromethane extraction. It is then introduced into a heat treatment device to obtain a microporous membrane. The heat treatment temperature is adjusted in the range of 130 to 135°C. The thickness is adjusted to approximately 9μm. For this microporous membrane, the dispersion of the resin is good, and the air permeability and puncture strength as a microporous membrane are also good. The results are shown in Tables 11 and 12. The film forming results of Examples 2.1 to 2.22 show that the microporous film-forming resin raw material composition of the present disclosure has no problem in the film forming property and product properties of the microporous film.

[0249] 《Comparative Examples 2.1 to 2.5》

[0250] For Comparative Example 2.1, LQ was not added, and the powder and pellets were made into a microporous membrane resin raw material composition by dry mixing with the same composition as Example 2.4. Due to the absence of LQ, the powder and pellets were completely separated, and dust was also flying during transportation and classification in the hopper. Although the manufacturing methods of Comparative Examples 2.2 to 2.4 were based on the same method as Example 2.1, the performance was not sufficient.

[0251] Comparative Examples 2.3 and 2.4 are the same as Example 2.1 except for the composition. For Comparative Example 2.5, all the raw materials were added at once in step a and stirred for 20 minutes, and step b was not performed. In Comparative Example 2.3, the adhesion between the powder and the granules was insufficient, resulting in classification and dust. In Comparative Examples 2.4 and 2.5, there were too many liquid components and they were all adhesive. Therefore, a large number of PWL10 particles and PWL0 particles were produced. In Comparative Example 2.5, since all the raw materials of the granules, powders, and liquid components were stirred at once, no single particles were produced and all were PWL10 or above. As a result, the dispersibility and piping transportability were significantly deteriorated.

[0252] For Comparative Examples 2.1 to 2.5, the microporous film forming properties and physical properties were confirmed by using the microporous film resin raw material compositions described in Tables 9 and 10 as they were. They had problems in the dispersion of the raw material composition, so they planned to invest in an extruder to form a film. All of them were confirmed to have poor dispersion, especially Comparative Example 2.4, which had very poor dispersion, had many fish eyes, and had a significantly lower puncture strength than other cases.

[0253] Reference Example

[0254] Only the powder (PW2) described in Table 7 was used as a microporous membrane resin raw material composition, and dispersibility, pipe transportability, classification property, dust generation property, bulk density variation, angle of repose, and fisheye were evaluated.

[0255] [Table 6]

[0256] Table 6. Pellets

[0257]

[0258] HDPE1: High-density polyethylene (viscosity average molecular weight 200,000)

[0259] PP: Polypropylene (viscosity average molecular weight 950,000)

[0260] EL: Elastomer (viscosity average molecular weight 60,000)

[0261] [Table 7]

[0262] Table 7. Powders

[0263] PW1 HDPE2 Average particle size 200μm, Mv 6 million PW2 HDPE3 Average particle size 200μm, Mv 400,000 PW3 Packing 1 Primary particle size 13nm, dry silica PW4 Packing 2 Average particle size 3μm, talc PW5 PP2 Average particle size 200μm Mv1 million

[0264] [Table 8]

[0265] Table 8. Liquid ingredients

[0266] LQ1 <![CDATA[Liquid paraffin, kinematic viscosity 68mm 2 / s (cst)]]>

[0267] [Table 9]

[0268]

[0269] [Table 10]

[0270]

[0271] [Table 11]

[0272]

[0273] [Table 12]

[0274]

[0275] Industrial Applicability

[0276] The resin raw material composition disclosed herein has good dispersibility, pipe conveyability and formability, less dusting and classification, and obtains various good formed products of physical properties. For example, in the manufacture of packaging film and microporous film, in the use of powder and pellets for extrusion molding at the same time, the dispersibility of the components of pellets and powder is good, and there is no generation of dust after the mixing of powder and pellets. During piping transportation, it will not be classified or attached to the piping and can be well transported, even if it will not produce classification in the hopper, extrusion molding is also good, and the obtained film and microporous film have very few formed products of fish eyes. Thus, for example, there is the industrial availability of separators such as packaging films, lithium ion secondary batteries, etc. with excellent forming processability and dispersibility.

[0277] Description of Reference Numerals

[0278] 10 Resin raw material composition disclosed herein

[0279] 20 Conventional resin raw material composition

Claims

1. A resin raw material composition comprising resin pellets (PL), powder (PW) and a liquid component (LQ), The resin raw material composition is a molding resin raw material composition, The resin raw material composition comprises: at least a part of the surface of the resin pellets is covered by the liquid component, the resin pellets covered by the liquid component are single particles or aggregates of a plurality of particles, and the powder is attached to the liquid component. Based on the total mass of the resin raw material composition, the ratio of the mass % of the resin pellets to the mass % of the powder (PL / PW) is 0.01 or more and 100 or less, and the ratio of the mass % of the resin pellets to the mass % of the liquid component (PL / LQ) is 1 or more and 199 or less, The number of granules including aggregates composed of 10 or more of the resin pellets is 20% or less based on the total number of granules.

2. A resin raw material composition comprising resin pellets (PL), powder (PW) and a liquid component (LQ), The resin raw material composition is a resin raw material composition for a microporous membrane, The resin raw material composition comprises: at least a part of the surface of the resin pellets is covered by the liquid component, the resin pellets covered by the liquid component are single particles or aggregates of a plurality of particles, and the powder is attached to the liquid component. Based on the total mass of the resin raw material composition, the ratio of the mass % of the resin pellets to the mass % of the powder (PL / PW) is 0.01 or more and 100 or less, and the ratio of the mass % of the resin pellets to the mass % of the liquid component (PL / LQ) is 1 or more and 199 or less, The number of granules including aggregates composed of 10 or more of the resin pellets is 20% or less based on the total number of granules.

3. The resin raw material composition according to claim 1 or 2, wherein The ratio of the mass % of the resin pellets to the mass % of the powder (PL / PW) is 0.11 or more and 19 or less.

4. The resin raw material composition according to claim 1 or 2, wherein The ratio of the mass % of the resin pellets to the mass % of the powder (PL / PW) is 2.3 or more and 9 or less.

5. The resin raw material composition according to claim 1 or 2, wherein The ratio of the mass % of the resin pellets to the mass % of the liquid component (PL / LQ) is 1 or more and 99 or less.

6. The resin raw material composition according to claim 1 or 2, wherein The ratio of the mass % of the resin pellets to the mass % of the liquid component (PL / LQ) is 4 or more and 32.3 or less.

7. The resin raw material composition according to claim 1 or 2, wherein The ratio of the mass % of the powder to the mass % of the liquid component (PW / LQ) is 0.25 or more and 99 or less.

8. The resin raw material composition according to claim 1 or 2, wherein The ratio of the mass % of the powder to the mass % of the liquid component (PW / LQ) is 0.67 or more and 9 or less. 9 . The resin raw material composition according to claim 1 , comprising, as a main component, granules in which the powder is attached to the liquid component of the resin pellets covered with the liquid component.

10. The resin raw material composition according to claim 9, wherein The granular material of the powder accounts for 50% by mass or more of the total mass of the resin raw material composition.

11. The resin raw material composition according to claim 1 or 2, wherein Taking the total number of granules as a benchmark, the number of granules containing single particles of the resin granules or aggregates of 2 to 9 particles is more than 95%, and taking the total mass of the resin raw material composition as a benchmark, the number of granules with a particle size of more than 10 mm is less than 1 mass%.

12. The resin raw material composition according to claim 1 or 2, wherein Taking the total number of granules as a benchmark, the number of granules including individual particles of the resin granules is more than 70%, and the maximum diameter of the granules including individual particles of the resin granules is greater than the particle size of the resin granules and less than the particle size of the resin granules + 5 mm.

13. The resin raw material composition according to claim 12, wherein Taking the total number of granules as a benchmark, the number of granules including individual particles of the resin granules is more than 70%, and the maximum diameter of the granules including individual particles of the resin granules is greater than the particle size of the resin granules and less than the particle size of the resin granules + 1 mm.

14. The resin raw material composition according to claim 1 or 2, wherein The number of granules composed of aggregates of a plurality of particles of the resin pellets is less than 30% based on the total number of granules, and When the resin raw material composition further includes granules composed of the powder and the liquid component without the resin pellets, the number of granules without the resin pellets is less than 20% based on the total number of granules.

15. The resin raw material composition according to claim 14, wherein The number of granules composed of aggregates of a plurality of particles of the resin pellets is less than 20% based on the total number of granules, and When the resin raw material composition further includes granules composed of the powder and the liquid component without the resin pellets, the number of granules without the resin pellets is less than 10% based on the total number of granules.

16. The resin raw material composition according to claim 1 or 2, wherein The number of granules including aggregates composed of 10 or more of the resin pellets is 1% or less based on the total number of granules.

17. The resin raw material composition according to claim 1 or 2, wherein The resin pellets contain at least one selected from the group consisting of polyolefin, PET, polyamide, aromatic polyamide, polyvinyl chloride, synthetic rubber, ABS and PPE.

18. The resin raw material composition according to claim 17, wherein The resin pellets contain 50% by mass or more of a polyolefin based on the total mass of the resin pellets.

19. The resin raw material composition according to claim 17, wherein The viscosity average molecular weight (Mv) of the resin in the resin pellets is 100,000 or more and 1,000,000 or less.

20. The resin raw material composition according to claim 17, wherein The viscosity average molecular weight (Mv) of the resin in the resin pellets is 200,000 or more and 600,000 or less.

21. The resin raw material composition according to claim 1 or 2, wherein The particle size of the resin pellets is 1 mm to 10 mm.

22. The resin raw material composition according to claim 1 or 2, wherein The powder (PW) has an average diameter of 10 μm or more and 300 μm or less.

23. The resin raw material composition according to claim 1 or 2, wherein The powder contains at least one selected from the group consisting of polyethylene, elastomer, PET, polyamide, aramid, and inorganic particles.

24. The resin raw material composition according to claim 23, wherein The powder is a polyethylene powder having a viscosity average molecular weight (Mv) of 200,000 to 10,000,000.

25. The resin raw material composition according to claim 1 or 2, wherein The particle size of the powder is 10 nm or more and 50 μm or less.

26. The resin raw material composition according to claim 1 or 2, wherein The particle size of the powder is 5 nm or more and 1 μm or less.

27. The resin raw material composition according to claim 1 or 2, wherein The liquid component is at least one selected from the group consisting of lubricating oil, mineral oil and liquid paraffin.

28. The resin raw material composition according to claim 1 or 2, wherein The bulk density of the resin raw material composition is 0.1 g / cm 3 ~2g / cm 3 .

29. The resin raw material composition according to claim 1 or 2, wherein The resin raw material composition has a bulk density with a variation of 10% or less.

30. The resin raw material composition according to claim 1 or 2, wherein The resin raw material composition has a bulk density with a variation of 3% or less.

31. The resin raw material composition according to claim 1 or 2, wherein The angle of repose of the resin raw material composition is 30° or more and 55° or less.

32. A method for producing the resin raw material composition according to any one of claims 1 and 3 to 31, wherein: The resin raw material composition is a molding resin raw material composition, The method for producing the resin raw material composition comprises: a covering step of kneading the resin pellets and the liquid component using a mixer, thereby covering at least a portion of the surface of the resin pellets with the liquid component; and The attachment step is a step of adding powder to the mixer after the covering step and further kneading the powder to attach the powder to the liquid component of the resin pellets covered with the liquid component.

33. The method for producing a resin raw material composition according to claim 32, wherein The torque rise time is within 150 seconds.

34. A method for producing a resin raw material composition according to any one of claims 2 to 31, wherein The resin raw material composition is a resin raw material composition for a microporous membrane, The method for producing the resin raw material composition comprises: a covering step of kneading the resin pellets and the liquid component using a mixer, thereby covering at least a portion of the surface of the resin pellets with the liquid component; and The attachment step is a step of adding powder to the mixer after the covering step and further kneading the powder to attach the powder to the liquid component of the resin pellets covered with the liquid component.

35. The method for producing a resin raw material composition according to claim 34, wherein The torque rise time is within 150 seconds.

36. A method for producing a mixed composition, comprising: A step of producing a resin raw material composition using the method for producing a resin raw material composition according to claim 34 or 35; and A step of further mixing resin pellets (PL) and / or powder (PW) which are the same as or different from the resin pellets (PL) and the powder (PW) into the resin raw material composition.

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