JP7254251B2 - Polypropylene resin composition, molded article and product - Google Patents

Description

The present disclosure relates to polypropylene-based resin compositions, molded articles and products.

Thermoplastic resins are lighter and easier to process than metals, and their molded articles are used in various applications such as home appliances and housings. Contamination such as dust may adhere to these thermoplastic resin moldings depending on the environment in which they are used. If dirt adheres to the molded product, the appearance of the molded product deteriorates, and the performance of the product may be deteriorated. There is a method of coating the surface with an antifouling material, but there is a problem that the coating is removed by wiping and the effect does not last. Therefore, various kneading-type resin molded products have been proposed to suppress adhesion of dirt.

For example, Patent Document 1 (JP-A-2001-278985) discloses a block copolymer consisting of an olefin block and a hydrophilic polymer block, and Patent Document 2 (JP-A-2016-23254) discloses a polyether ester high A molecular type antistatic agent is disclosed.

Further, Patent Document 3 (Japanese Patent Application Laid-Open No. 2018-062554) discloses a composition containing a silicone compound and having a water-repellent effect. Furthermore, Patent Document 4 (International Publication No. 2019/069503) discloses a composition containing a modified silicone compound and having an antifouling effect against oil.

Japanese Unexamined Patent Application Publication No. 2001-278985 JP 2016-23254 A JP 2018-062554 A WO2019/069503

As described above, the antistatic agents disclosed in Patent Documents 1 and 2 are effective against charged substances such as dust. The composition described in Patent Document 3 is recognized to be effective against water-based stains, and the composition described in Patent Document 4 is recognized to be effective against oil-based stains.

However, dust includes hydrophilic dust (sand dust, dust, etc.) and hydrophobic dust (soot, oily smoke, etc.), and liquid dirt includes water-based dirt and oil-based dirt. These soils have contradictory properties, being hydrophilic and hydrophobic, or water-based and oil-based. For this reason, it is difficult to suppress the adhesion of all dirt simply by adding the materials used in the above-described conventional techniques, and some dirt may become more likely to adhere.

An object of the present disclosure is to provide a polypropylene-based resin composition having an antifouling effect against all hydrophilic dust, hydrophobic dust, water-based stains and oil-based stains.

The polypropylene-based resin composition of the present embodiment is
a polypropylene-based resin (A);
a copolymer (B) having a first block comprising hydrophilic polyether chains;
and a silicone compound (C),
The molar ratio of oxygen to carbon in the elements constituting the hydrophilic polyether chain is 0.3 or more,
The silicone compound (C) is a silicone graft copolymer or high molecular weight silicone.

According to the present disclosure, it is possible to provide a polypropylene resin composition that can suppress both hydrophilic dust stains and hydrophobic dust stains, and can suppress both water-based and oil-based liquid stains.

2 is a conceptual diagram showing the behavior of each component during molding of the polypropylene-based resin composition according to Embodiment 1. FIG. FIG. 5 is a schematic cross-sectional view showing an example of a molded product according to Embodiment 2; 7 is a graph showing composition distribution in the depth direction for an example of a molded product according to Embodiment 2. FIG.

Embodiments of the present disclosure will be described below. In the drawings, dimensional relationships such as length, width, thickness, and depth are changed as appropriate for clarity and simplification of the drawings, and do not represent actual dimensional relationships.

Embodiment 1.
The polypropylene-based resin composition of the present embodiment is
a polypropylene-based resin (A);
a copolymer (B) having a first block comprising hydrophilic polyether chains;
a silicone compound (C);
contains
The molar ratio of oxygen to carbon in the elements constituting the hydrophilic polyether chain is 0.3 or more,
The silicone compound (C) is a silicone graft copolymer or high molecular weight silicone.

The polypropylene-based resin composition of the present embodiment and the molded article containing the same have a remarkable antifouling effect against all hydrophilic dust, hydrophobic dust, water-based stains and oil-based stains. Antifouling effect is exhibited.

Note that such a remarkable effect is exhibited by blending both the component (B) and the component (C) with the component (A), and when only the component (B) is blended with the component (A), and when the component (B) is blended with the component (A) When only component (C) is added to (A), it is difficult to obtain such a remarkable antifouling effect.

<Polypropylene resin (A)>
The polypropylene-based resin is not particularly limited, and may be a propylene homopolymer, a block copolymer, or a random copolymer. A homopolymer of propylene is preferable from the viewpoint of the rigidity and heat resistance of the molded article obtained using the polypropylene-based resin composition of the present embodiment. A block copolymer is preferable from the viewpoint of the impact resistance of the molded article obtained using the polypropylene-based resin composition of the present embodiment. Polypropylene-based resins may be used singly or in combination of two or more.

Copolymers such as the above block copolymers and random copolymers are obtained by copolymerizing propylene and a monomer copolymerizable with propylene. Examples of the monomer include olefins such as ethylene, butene, pentene, hexene and octene, preferably ethylene or 1-butene. Two or more kinds of these monomers may be used. The ratio of the amount of the monomer used to the total amount (100% by mass) of all monomers used in the synthesis of the copolymer is usually 30% by weight or less, preferably 20% by weight or less.

The polypropylene-based resin may be obtained by synthesizing by a conventionally known method. You may use a commercial item.

The melt flow rate (MFR) of the polypropylene resin measured at a temperature of 230°C and a load of 2.16 kgf based on JIS K 7210 gives a composition with excellent processability and moldability, and the antifouling effect is enhanced. It is preferably 5 to 100 g/10 minutes, more preferably 8 to 60 g/10 minutes, from the viewpoint that a molded article such as an injection molded article can be easily obtained.

The Charpy impact strength (23° C.) of the polypropylene-based resin measured according to JIS K7111 is preferably 2 to 2, because it is possible to easily obtain a molded article such as an injection molded article having excellent impact resistance. 20 kJ/m ² .

The flexural modulus of the polypropylene-based resin measured according to JIS K7171 is preferably 1000 to 2500 MPa from the viewpoint that a molded article such as an injection molded article having excellent mechanical strength can be easily obtained.

The tensile modulus of the polypropylene-based resin, measured according to JIS K7161, is preferably 1000 to 2500 MPa from the viewpoint that molded articles such as injection molded articles having excellent mechanical strength can be easily obtained.

The content of the polypropylene-based resin (A) in the polypropylene-based resin composition (the ratio of the mass of the polypropylene-based resin (A) to the total amount of the polypropylene-based resin composition) is preferably 80 to 98% by mass, more preferably is 90 to 96% by mass.

<Copolymer (B) Having First Block Containing Hydrophilic Polyether Chain>
A hydrophilic polyether chain is a polyether chain formed by polymerizing hydrophilic or water-soluble monomers.

Since the first block containing hydrophilic polyether chains functions as a hydrophilic segment, the copolymer (B) having the first block containing hydrophilic polyether chains has hydrophilic properties.

The copolymer (B) is kneaded (for example, melt-kneaded) with another material, and the resulting kneaded product is molded to form a molded product. The striped copolymer (B) forms a conductive path, so that the molded product exhibits antistatic performance, and part of the hydrophilic dust and hydrophobic dust that adheres due to electrification. On the other hand, it expresses an adhesion suppressing effect. Therefore, by adding the copolymer (B) to the polypropylene-based resin composition, the antifouling effect of the molded article obtained from the polypropylene-based resin composition can be enhanced.

The first block is not particularly limited as long as it contains a hydrophilic polyether chain. The first block may be a block composed only of a hydrophilic polyether chain, or may contain a portion other than the hydrophilic polyether chain.

The hydrophilic polyether chain contained in the first block preferably has sufficiently high polarity and sufficiently high hydrophilicity. Specifically, for example, it is preferable that the monomer constituting the hydrophilic polyether chain has an affinity for water, such as ethylene glycol.

More specifically, in the elements constituting the hydrophilic polyether chain, the molar ratio (O/C) of oxygen (O) to carbon (C) is 0.3 or more. Such polyether chains have hydrophilic properties. If the O/C is smaller than this value, the hydrophilicity of the polyether chain is insufficient, so that the antistatic performance of the molded article obtained from the polypropylene resin composition is insufficient, and a high antifouling effect cannot be obtained. .

For example, when the hydrophilic polyether chain is a polyethylene glycol chain, the O/C of the polyethylene glycol chain is the same as the ratio (O/C) of its constituent units [-(OCH ₂ -CH ₂ )-]. Since the structural unit has one oxygen element and two carbon atoms, the O/C ratio of polyethylene glycol is 0.5. Further, when the hydrophilic polyether chain is a polypropylene glycol chain, the number of oxygen atoms in the constituent units of the polypropylene glycol chain is 1 and the number of carbon atoms is 3, so the O/C of polypropylene glycol is 0.33. is.

Thus, polyoxyethylene chains having an O/C of 0.3 or more, such as polyethylene glycol chains and polypropylene glycol chains, are included in the hydrophilic polyether chains in the present embodiment. Accordingly, specific examples of hydrophilic polyether chains contained in the first block include polyoxyethylene chains derived from polyethylene glycol, polypropylene glycol, and the like.

Copolymer (B) is preferably a copolymer having alternating first blocks and blocks (second blocks) composed of polyester or polyolefin. The second block composed of polyester or polyolefin has compatibility with the polypropylene-based resin (A) as a hydrophobic segment. Therefore, by having the copolymer (B) alternately having the first blocks and the second blocks, the dispersibility of the copolymer (B) in the polypropylene resin (A) can be enhanced. This allows the antistatic performance of the first block to function on the entire surface of the polypropylene-based resin composition.

Two or more types of copolymers (B) having different second blocks can be used by mixing them at any ratio as long as each of them satisfies the above functions. For example, even if a second block composed of polyester and a second block composed of polyolefin are mixed and used, each copolymer exhibits the above functions. Therefore, the copolymer (B) may be a mixture of a copolymer of the first block and a second block composed of polyester and a copolymer of the first block and a second block composed of polyolefin. , the antifouling property of the molded article made of the polypropylene-based resin composition can be enhanced.

However, it is preferred that the hydrophilicity of the second block is no greater than the polyether chains of the first block.

For example, it is not preferred to use polyetheresteramide as copolymer (B). Polyetheresteramides are block-type copolymers containing hydrophilic segments (first block) consisting of polyoxyethylene chains and blocks of polyallide chains. The second block imparts hydrophobicity to the copolymer (B) and imparts compatibility with the polypropylene resin (A), thereby improving the dispersibility of the copolymer (B) in the polyolefin resin (A). can be enhanced. However, since the polyamide has many polar groups, the polarity is too high and compatibility with the polypropylene resin (A) cannot be obtained, and the copolymer (B) in the polyolefin resin (A) cannot be dispersed. because it cannot As described above, the study by the present inventors revealed that polyether ester amide is not preferable as the copolymer (B).

Copolymer (B) can be produced by various known methods, and copolymer (B) can also be purchased commercially.

For example, a copolymer having alternating first blocks (blocks containing a hydrophilic polyether chain) and second blocks (blocks composed of a polyester) can be prepared by, for example, the method described in WO 2019/021943. can be obtained using

Further, a copolymer obtained by repeatedly and alternately binding a block (first block) derived from a hydrophilic polymer having a polyoxyethylene chain and a block (second block) composed of a polyolefin is disclosed, for example, in JP-A-2001. As described in JP-A-278985 (Patent Document 1) and JP-A-2003-48990, it can be obtained by acid-modifying polypropylene or polyethylene and reacting it with polyalkylene glycol.

The copolymer (B) having a first block containing a hydrophilic polyether chain is dispersed in the polypropylene-based resin composition when mixed with the polypropylene-based resin (A) or the like, but the molded article obtained from the polypropylene-based resin composition is characterized in that it gathers especially on the surface of the molded product and is present at a higher density than other parts. It is believed that this is because the copolymer (B) has a low melt viscosity and is extruded to the tip of the flow when subjected to a shearing force during the injection process during molding. Due to this feature, the antifouling effect is efficiently exhibited with respect to the amount of the copolymer (B) added. Therefore, compared with the case where a general hydrophilic polymer other than the copolymer (B) is added, the copolymer (B) can exhibit antifouling performance with a small amount.

In this way, the copolymer (B) is present in the vicinity of the surface of the molded article obtained from the polypropylene-based resin composition, thereby particularly enhancing the antistatic effect of the molded article. Therefore, it is generally preferred that the surface resistance of the copolymer (B) itself is as low as possible. The surface resistance value of the copolymer (B) is preferably 1×10 ⁴ to 1×10 ¹⁰ Ω, more preferably 1×10 ⁴ to 1×10 ⁷ Ω.

In the present embodiment, it is preferable to select the amount and type of the second block so that the copolymer (B) has such surface resistance and sufficient dispersibility in the polypropylene resin.

The content of the copolymer (B) in the polypropylene-based resin composition is preferably 1-15% by mass, more preferably 2-12% by mass.

In addition, the polypropylene-based resin composition is used for the purpose of improving the effect of suppressing the adhesion of some of the hydrophilic and hydrophobic dust stains that adhere due to the electrostatic property, other than the above-mentioned copolymer (B). It may further contain an agent. Other antistatic agents include, for example, surfactants, ionic liquids, and the like.

<Silicone compound (C)>
Component (C) used in the present invention is a silicone compound.

Since the silicone compound (C) generally has a low surface free energy (surface tension), the silicone compound (C) has the effect of reducing the surface free energy of the polypropylene-based resin composition. By reducing the surface free energy, the intermolecular force between the surface of the polypropylene resin composition and dirt is reduced, and adhesion of hydrophilic and hydrophobic dust dirt and water-based and oil-based dirt is reduced. , can be suppressed.

Therefore, as the silicone compound (C), it is preferable to use a compound that is highly effective in reducing the surface free energy of the polypropylene-based resin composition. In order to lower the surface free energy of the polypropylene-based resin composition, it is preferable to use a silicone compound (C) having a low surface free energy.

Examples of silicone compounds include silane monomers, silicone oils, silicone powders, organically modified silicone oils, high-molecular-weight silicones, and silicone-modified resins.

Among these, the bleed-out from the surface of the polypropylene resin composition is suppressed, the effect of suppressing the adhesion of dust (hydrophilic dust and hydrophobic dust) over a long period of time, and the antifouling effect against water-based and oil-based stains is sustained. In particular, high-molecular-weight silicones and silicone-modified resins are preferable.

The molecular weight of the high molecular weight silicone is preferably 5,000 or more, more preferably 10,000 or more.

As the high-molecular-weight silicone, it is desirable to use a mixture kneaded with a polypropylene-based resin. In this case, the effect of enhancing the dispersibility of the silicone compound (C) in the polypropylene resin can be obtained.

Examples of high-molecular-weight silicones include silicone compounds obtained by kneading dimethylpolysiloxane and polypropylene-based resins. In the present embodiment, as the polypropylene-based resin (A) and the silicone compound (C), commercially available products obtained by pre-kneading such a high-molecular-weight silicone and a polypropylene-based resin may be used.

Examples of silicone-modified resins include block copolymers and graft copolymers (silicone graft copolymers) in which silicone is chemically bonded to resins (such as polypropylene-based resins).

In particular, the silicone compound (C) is preferably a silicone graft copolymer obtained by graft polymerization of silicone and resin. In this case, when the silicone compound (C) is added to the polypropylene resin (A), more of the silicone portion of the silicone compound (C) (a portion containing a siloxane bond) is exposed on the surface of the polypropylene resin composition. , the surface free energy of the polypropylene-based resin composition can be further lowered.

The silicone graft copolymer is preferably a copolymer (silicone graft polymerization polypropylene) obtained by graft polymerization of silicone and polypropylene resin.

Silicone-graft-polymerized polypropylene can be obtained, for example, by chemically bonding (grafting) organopolysiloxane to polypropylene molecular chains of a polypropylene-based resin. Specifically, for example, by melt-kneading polypropylene, organopolysiloxane, and organic peroxide, it is possible to produce silicone-graft-polymerized polypropylene. Such a manufacturing method is a known technique, and one example is disclosed in Japanese Patent Application Laid-Open No. 6-16824.

Polypropylene-based resins constituting silicone graft polymerized polypropylene include, for example, propylene homopolymers, copolymers (block copolymers, random copolymers, etc.) of propylene and α-olefins other than propylene (ethylene, butene-1, etc.). polymers, graft copolymers, etc.), mixtures thereof, and the like.

Moreover, the skeleton of the organopolysiloxane that constitutes the silicone graft polymerized polypropylene may be at least one of linear, branched, and cyclic.

Examples of organopolysiloxanes include dimethylsiloxane, methylphenylpolysiloxane, methylhydrodienepolysiloxane, both-terminal trimethylsiloxy group-blocked polymethylvinylsiloxane, and both-terminal trimethylsiloxy group-blocked dimethylsiloxane-methylhexenyl copolymer. is mentioned.

By exposing the silicone part contained in the silicone compound (C) to the outermost surface of the molded article obtained from the polypropylene resin composition, the surface free energy of the polypropylene resin composition is reduced, and the copolymer (B) is A synergistic effect with the antistatic effect is exhibited. As a result, a remarkable antifouling effect is exhibited against both hydrophilic dust and hydrophobic dust.

The silicone portion contained in the silicone compound (C) exerts water-repellent and oil-repellent effects, improving the antifouling effect against both water-based stains and oil-based stains.

When the silicone part contained in the silicone compound (C) is exposed on the outermost surface of the polypropylene-based resin composition, it is possible to efficiently obtain an antifouling effect against both water-based stains and oil-based stains.

The content of the silicone compound (C) in the polypropylene resin composition is preferably 0.1 to 10% by mass, more preferably 0.3 to 6% by mass.
<Surfactant>
The polypropylene-based resin composition of the present embodiment may further contain a surfactant in order to improve antifouling properties.

Examples of surfactants include anionic surfactants, cationic surfactants, nonionic surfactants, and amphoteric surfactants.

Examples of anionic surfactants include alkylsulfonates and alkylbenzenesulfonates.

Cationic surfactants include quaternary ammonium salts such as alkyltrimethylammonium salts and alkylbenzyldimethylammonium salts.

Examples of nonionic surfactants include glycerin fatty acid esters, fatty acid diethanolamides, alkyldiethanolamines, and the like.

Amphoteric surfactants include alkyl betaine, alkyl imidazolium betaine and the like.

These can be used alone or in combination of two or more.
In particular, alkyl benzene sulfonates, glycerin fatty acid esters, and the like are preferable as surfactants in terms of enhancing the antistatic effect and further improving the antifouling property. Alkylbenzenesulfonates include, for example, sodium alkylbenzenesulfonate.

When the polypropylene-based resin composition contains a surfactant, the content of the surfactant is preferably 0.1 to 5% by mass with respect to the total amount of the polypropylene-based resin composition. By including a surfactant, the antistatic effect is further enhanced, and the effect of suppressing adhesion of dirt is improved.

<Nucleating agent>
The polypropylene-based resin composition of the present embodiment may further contain a nucleating agent in order to improve mechanical properties during production and product use.

In a molded product made of resin, creep occurs due to continuous application of a load, and creep rupture, creep deformation, and the like occur. When a molded article made of the polypropylene-based resin composition of the present embodiment is used, for example, as a part to which stress is continuously applied, it is particularly preferable to mix a nucleating agent in the polypropylene-based resin composition. By including a nucleating agent in the polypropylene-based resin composition, the mechanical properties of the molded product can be improved, the creep rupture time can be extended, and the amount of creep deformation can be reduced.

As the nucleating agent, inorganic nucleating agents and organic nucleating agents can be used. Talc etc. are mentioned as an inorganic nucleating agent. Examples of organic nucleating agents include aromatic carboxylic acid metal salts, alicyclic alkyl carboxylic acid metal salts, p-tert-butyl aluminum benzoate, aromatic phosphate metal salts, dibenzylidene sorbitols and the like.

Specific examples of organic nucleating agents include sodium-2,2'-methylenebis(4,6-di-tert-butylphenyl)phosphate, lithium-2,2'-methylenebis(4,6-di-tert-butyl phenyl)phosphate, aluminum hydroxybis[2,2'methylenebis(4,6-di-tert-butylphenyl)phosphate], sodium benzoate, hydroxyaluminum di-p-tert-butylbenzoate, sodium adipate, dibenzylidene Sorbitol, bis(methylbenzylidene)sorbitol, bis(3,4-dimethylbenzylidene)sorbitol, bis(p-ethylbenzylidene)sorbitol, and bis(dimethylbenzylidene)sorbitol, N,N'-dicyclohexylnaphthalene dicarboxamide, N,N ',N''-tris[2-methylcyclohexyl]-1,2,3-propanetricarboxamide, N,N',N''-tricyclohexyl-1,3,5-benzenetricarboxamide, N,N'-dicyclohexyl naphthalene dicarboxamide, 1,3,5-tri(dimethylisopropoylamino)benzene and the like.

Dibenzylidene sorbitols and aromatic phosphate metal salts are particularly preferred from the viewpoint of improving the mechanical properties of molded articles.

When the polypropylene-based resin composition contains a nucleating agent, the content of the nucleating agent in the polypropylene-based resin composition is preferably 0.01 to 1 mass%, more preferably 0.02 to 0. .6 mass %.

<Inorganic filler>
The polypropylene-based resin composition of the present embodiment may contain an inorganic filler instead of or in combination with a nucleating agent in order to improve mechanical properties during production and product use.

Examples of inorganic fillers include talc, wollastonite, mica, clay, montmontlilonite, smectite, kaolin, calcium carbonate, glass fibers, glass beads, glass balloons, glass milled fibers, glass flakes, carbon fibers, and carbon flakes. , carbon beads, carbon milled fibers, metal flakes, metal fibers, metal-coated glass fibers, metal-coated carbon fibers, metal-coated glass flakes, silica, ceramic particles, ceramic fibers, ceramic balloons, aramid particles, aramid fibers, polyarylate fibers, Various whiskers such as graphite, potassium titanate whisker, aluminum borate whisker, and basic magnesium sulfate are included. Among them, silicate-based fillers such as talc, wollastonite, mica, glass fiber, and glass milled fiber are preferably used. Among them, talc, glass fiber and glass wool are particularly preferred.

The talc preferably contains few impurities. Also, the whiteness of talc is preferably 94% or more, more preferably 96% or more. In order to increase the effect of improving mechanical properties, the particle size of talc is preferably 15 μm or less, more preferably 5 μm or less.

The glass fiber preferably has a fiber length of 2 to 4 mm and a fiber diameter of 14 to 10 μm in order to enhance the effect of improving mechanical properties.

The glass wool preferably has a fiber length of 1 mm or less and a fiber diameter of 3 to 8 μm.

When blending an inorganic filler, the polypropylene resin composition of the present embodiment further contains an acidic group such as a carboxylic acid anhydride group or a sulfonic acid group in order to improve the wettability of the inorganic filler. Additives may be added.

The amount of the inorganic filler added in the present embodiment is preferably 0.1 to 30 parts by mass, more preferably 0.5 to 20 parts by mass, more preferably 1 part by mass with respect to 100 parts by mass of the polypropylene resin composition. ~10 parts by mass. If the amount added is less than 0.1 parts by mass, the reinforcing effect of the inorganic filler is weak, and if it exceeds 30 parts by mass, the impact strength may significantly decrease.

<Optional component>
The polypropylene-based resin composition of the present embodiment is substantially formed from a polypropylene-based resin (A), a copolymer having a first block containing a hydrophilic polyether chain (B), and a silicone compound (C). However, other polymers other than the above may be contained in an amount that does not impair the effects of the present disclosure. Other polymers include, for example, α-olefin copolymers.

Examples of such α-olefin copolymers include polyethylene, ethylene-butene copolymer, ethylene-pentene copolymer, ethylene-hexene copolymer, ethylene-octene copolymer, propylene-butene copolymer. propylene-hexene copolymers, propylene-octene copolymers, butene-hexene copolymers, butene-octene copolymers, hexene-octene copolymers, and the like.

In addition, the polypropylene-based resin composition of the present embodiment includes optional components such as antioxidants, ultraviolet absorbers, light stabilizers, antibacterial agents, and antifungal agents as long as the effects of the present embodiment are not impaired. It may contain components such as

(Antioxidant)
The polypropylene-based resin composition of the present embodiment may contain an antioxidant in order to improve thermal stability during production and use.

As the antioxidant, it is preferable to use a phosphorus-based antioxidant and/or a phenol-based antioxidant, and it is more preferable to use them in combination.

The amount of the phosphorus-based antioxidant and/or the phenol-based antioxidant added to the polypropylene-based resin composition of the present embodiment is not particularly limited.

From the viewpoint of effectively obtaining the effect of improving thermal stability and not affecting the blending amount of each of the above essential components, the amount of the phosphorus antioxidant and/or the phenolic antioxidant to be added is It is preferably 0.01 to 1 part by mass, more preferably 0.01 to 0.6 part by mass with respect to 100 parts by mass of the polypropylene resin composition.

Phosphorous antioxidants include phosphorous acid, phosphoric acid, phosphonous acid, phosphonic acid, esters thereof, phosphonite compounds, tertiary phosphines, and the like.

Phosphites (phosphite compounds) include triphenylphosphite, tris(nonylphenyl)phosphite, tridecylphosphite, distearylpentaerythritol diphosphite, bis(2,4-di-tert-butylphenyl ) pentaerythritol diphosphite, bis(2,6-di-tert-butyl-4-methylphenyl)pentaerythritol diphosphite, bis{2,4-bis(1-methyl-1-phenylethyl)phenyl}penta Erythritol diphosphite, phenylbisphenol A pentaerythritol diphosphite, bis(nonylphenyl)pentaerythritol diphosphite, dicyclohexylpentaerythritol diphosphite and the like.

As the phosphite (phosphite compound), in addition to those mentioned above, those having a cyclic structure by reacting with dihydric phenols can also be used.

For example, 2,2′-methylenebis(4,6-di-tert-butylphenyl)(2,4-di-tert-butylphenyl)phosphite, 2,2′-methylenebis(4,6-di-tert- butylphenyl)(2-tert-butyl-4-methylphenyl)phosphite and 2,2-methylenebis(4,6-di-tert-butylphenyl)octylphosphite.

Phosphate esters (phosphate compounds) include triphenyl phosphate, trimethyl phosphate, and the like.

Phosphonite compounds include tetrakis(di-tert-butylphenyl)-biphenylenediphosphonite, bis(di-tert-butylphenyl)-phenyl-phenylphosphonite, and the like.

The phosphonite compound can be used in combination with the above-described phosphite compound having two or more aryl groups as alkyl group substituents, and is preferred.

Phosphonate esters (phosphonate compounds) include dimethyl benzenephosphonate, diethyl benzenephosphonate, and dipropyl benzenephosphonate.

Tertiary phosphines include triphenylphosphine and the like.
Phosphonite compounds and phosphite compounds are preferred among the phosphorus-based antioxidants.

As the phosphonite compound, tetrakis(2,4-di-tert-butylphenyl)-biphenylenediphosphonite is preferred.

More preferred phosphite compounds are distearylpentaerythritol diphosphite, bis(2,4-di-tert-butylphenyl)pentaerythritol diphosphite, bis(2,6-di-tert-butyl-4-methyl Phenyl)pentaerythritol diphosphite, 3,9-bis(2,6-di-tert-butyl-4-methylphenoxy)-2,4,8,10-tetraoxa-3,9-diphosphapyro[5,5] undecane and bis{2,4-bis(1-methyl-1-phenylethyl)phenyl}pentaerythritol diphosphite.

As the phenol compound, for example, hindered phenol compounds and semi-hindered phenol compounds can be used. Hindered phenols and semi-hindered phenols include, for example, tetrakis[methylene-3-(3-tert-butyl-4-hydroxy-5-methylphenyl)propionate]methane, octadecyl-3-(3,5- Di-tert-butyl-4-hydroxyphenyl)propionate, and 3,9-bis[2-{3-(3-t-butyl-4-hydroxy-5-methylphenyl)propionyloxy}-1,1-dimethyl ethyl]-2,4,8,10-tetraoxaspiro[5,5]undecane and the like.

The polypropylene-based resin composition of the present embodiment can optionally contain antioxidants other than the phosphorus-based antioxidant and the phenol-based antioxidant.

The other antioxidant is preferably used in combination with at least one of a phosphorus antioxidant and a phenolic antioxidant, and particularly used in combination with both a phosphorus antioxidant and a phenolic antioxidant. is preferred.

Other antioxidants include, for example, lactone antioxidants represented by reaction products of 3-hydroxy-5,7-di-tert-butyl-furan-2-one and o-xylene (this oxidation For details of inhibitors, see JP-A-7-233160).

The amount of the lactone antioxidant added is preferably 0.0005 to 0.05 parts by mass, more preferably 0.001 to 0.03 parts by mass, per 100 parts by mass of the polypropylene resin composition.

Other antioxidants include sulfur-containing antioxidants such as pentaerythritol tetrakis (3-mercaptopropionate), pentaerythritol tetrakis (3-laurylthiopropionate), and glycerol-3-stearylthiopropionate. are mentioned.

The addition amount of other antioxidants other than the phosphorus-based antioxidant and/or the phenol-based antioxidant in the polypropylene-based resin composition of the present embodiment is not particularly limited, and the polypropylene-based resin composition is 100 parts by mass. , preferably 0.0005 to 0.1 parts by mass, more preferably 0.001 to 0.08 parts by mass, and particularly preferably 0.001 to 0.05 parts by mass.

(Ultraviolet absorber)
The polypropylene-based resin composition of the present embodiment may contain an ultraviolet absorber. In order to improve the weather resistance of the polypropylene-based resin composition of the present embodiment, it is effective to add an ultraviolet absorber.

Examples of the ultraviolet absorber of the present embodiment include a benzophenone-based ultraviolet absorber, a benzotriazole-based ultraviolet absorber, a hydroxyphenyltriazine-based ultraviolet absorber, a cyclic imino ester-based ultraviolet absorber, and a cyanoacrylate-based ultraviolet absorber. An ultraviolet absorber etc. are mentioned.

Benzophenone-based UV absorbers include, for example, 2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-octoxybenzophenone, 2-hydroxy-4-benzyloxybenzophenone, 2-hydroxy -4-methoxy-5-sulfoxybenzophenone, 2-hydroxy-4-methoxy-5-sulfoxytrihydrate benzophenone, 2,2'-dihydroxy-4-methoxybenzophenone, 2,2',4,4'- Tetrahydroxybenzophenone, 2,2'-dihydroxy-4,4'-dimethoxybenzophenone, 2,2'-dihydroxy-4,4'-dimethoxy-5-sodium sulfoxybenzophenone, bis(5-benzoyl-4-hydroxy -2-methoxyphenyl)methane, 2-hydroxy-4-n-dodecyloxybenzophenone, and 2-hydroxy-4-methoxy-2'-carboxybenzophenone.

Benzotriazole-based UV absorbers include, for example, 2-(2-hydroxy-5-methylphenyl)benzotriazole, 2-(2-hydroxy-5-tert-octylphenyl)benzotriazole, 2-(2 -hydroxy-3,5-dicumylphenyl)phenylbenzotriazole, 2-(2-hydroxy-3-tert-butyl-5-methylphenyl)-5-chlorobenzotriazole, 2,2′-methylenebis[4-( 1,1,3,3-tetramethylbutyl)-6-(2H-benzotriazol-2-yl)phenol], 2-(2-hydroxy-3,5-di-tert-butylphenyl)benzotriazole, 2-(2-hydroxy-3,5-di-tert-butylphenyl)-5-chlorobenzotriazole, 2-(2-hydroxy-3,5-di-tert-amylphenyl)benzotriazole, 2-( 2-hydroxy-5-tert-octylphenyl)benzotriazole, 2-(2-hydroxy-5-tert-butylphenyl)benzotriazole, 2-(2-hydroxy-4-octoxyphenyl)benzotriazole, 2,2′-methylenebis(4-cumyl-6-benzotriazolephenyl), 2,2′-p-phenylenebis(1,3-benzoxazin-4-one), 2-[2-hydroxy-3-( 3,4,5,6-tetrahydrophthalimidomethyl)-5-methylphenyl]benzotriazole and the like. Other benzotriazole-based UV absorbers are exemplified by polymers having a 2-hydroxyphenyl-2H-benzotriazole skeleton. Polymers having a 2-hydroxyphenyl-2H-benzotriazole skeleton include, for example, 2-(2′-hydroxy-5-methacryloxyethylphenyl)-2H-benzotriazole and a vinyl-based monomer copolymerizable therewith. and a copolymer of 2-(2'-hydroxy-5-acryloxyethylphenyl)-2H-benzotriazole and a vinyl monomer copolymerizable with the monomer.

Examples of hydroxyphenyltriazine-based UV absorbers include 2-(4,6-diphenyl-1,3,5-triazin-2-yl)-5-hexyloxyphenol, 2-(4,6-diphenyl- 1,3,5-triazin-2-yl)-5-methyloxyphenol, 2-(4,6-diphenyl-1,3,5-triazin-2-yl)-5-ethyloxyphenol, 2-( 4,6-diphenyl-1,3,5-triazin-2-yl)-5-propyloxyphenol, and 2-(4,6-diphenyl-1,3,5-triazin-2-yl)-5- butyloxyphenol and the like. Furthermore, the phenyl group of the above-exemplified compounds such as 2-(4,6-bis(2,4-dimethylphenyl)-1,3,5-triazin-2-yl)-5-hexyloxyphenol is 2, A compound substituted with a 4-dimethylphenyl group is exemplified.

Cyclic iminoester-based UV absorbers include, for example, 2,2′-p-phenylenebis(3,1-benzoxazin-4-one), 2,2′-(4,4′-diphenylene)bis( 3,1-benzoxazin-4-one), 2,2′-(2,6-naphthalene)bis(3,1-benzoxazin-4-one), and the like.

Examples of cyanoacrylate ultraviolet absorbers include 1,3-bis-[(2′-cyano-3′,3′-diphenylacryloyl)oxy]-2,2-bis[(2-cyano-3, 3-diphenylacryloyl)oxy]methyl)propane, 1,3-bis-[(2-cyano-3,3-diphenylacryloyl)oxy]benzene, and the like.

Furthermore, the UV absorber is a polymer-type UV-absorbing agent obtained by copolymerizing a UV-absorbing monomer and/or a photostable monomer having a hindered amine structure with a monomer such as an alkyl (meth)acrylate. It may be an agent. As the UV-absorbing monomer, a (meth)acrylic acid ester is preferably a compound containing a benzotriazole skeleton, a benzophenone skeleton, a triazine skeleton, a cyclic iminoester skeleton, and a cyanoacrylate skeleton in the ester substituent. exemplified.

Among the above, benzotriazole-based and hydroxyphenyltriazine-based UV absorbers are preferred in terms of UV absorption capacity, and cyclic iminoester-based and cyanoacrylate-based UV absorbers are preferred in terms of heat resistance and hue (transparency). is preferred. The ultraviolet absorbers may be used singly or as a mixture of two or more.

The amount of the ultraviolet absorbent to be added is preferably 0.01 to 2 parts by mass, more preferably 0.03 to 1 part by mass with respect to 100 parts by mass of the polypropylene resin composition.

(light stabilizer)
The polypropylene-based resin composition of the present embodiment may contain a light stabilizer. Since the polypropylene-based resin composition of the present embodiment may cause yellowing in the dark, it is effective to add a light stabilizer to prevent such deterioration.

Hindered amine light stabilizers (HALS) can be preferably used as light stabilizers.

As hindered amine light stabilizers (HALS), compounds derived from substituted piperidine compounds are preferred, and compounds derived from alkyl-substituted piperidyl, piperidinyl or piperazinone compounds, and substituted alkoxypiperidinyl compounds are more preferred.

(Antibacterial agent)
The polypropylene-based resin composition of the present embodiment may contain an antibacterial agent. Although the antibacterial agent is not particularly limited, for example, by adding an inorganic antibacterial agent, an organic antibacterial agent, or an inorganic/organic composite antibacterial agent, antibacterial properties can be imparted to the polypropylene resin composition. can.

As the inorganic antibacterial agent, for example, an antibacterial agent obtained by supporting an antibacterial metal or its metal ion on a carrier can be used.

Examples of antibacterial metals include silver, copper, zinc and the like, with silver and zinc being particularly preferred.

Examples of carriers include silicate-based carriers such as aluminosilicate, magnesium aluminometasilicate, and calcium silicate; phosphate-based carriers such as zirconium phosphate, calcium phosphate, and calcium phosphate reconstitute; silica, silica gel, and zinc oxide. , oxide-based carriers such as alkaline earth metal (hydrate) oxides, glass-based carriers such as soluble glass and composite glass, potassium titanate, activated alumina, diatomaceous earth, activated carbon, hydroxyapatite, magnesium oxide, perchlorine and magnesium acid.

Examples of inorganic antibacterial agents containing silver and/or zinc include Bactekiller BM-102-TG, BM-102-SD manufactured by Fuji Chemical Co., Ltd., and the like.

The amount of the inorganic antibacterial agent added is preferably 0.01 to 2 parts by mass, more preferably 0.1 to 1.5 parts by mass with respect to 100 parts by mass of the polypropylene resin composition.

As organic antibacterial agents, alcohol, phenol, ester, peroxide/epoxy, halogen, imidazole-thiazole, thiocarbamate, and surfactant antibacterial agents may be used. As an organic antibacterial agent, a glycerin fatty acid ester or the like may be used. When using a low-molecular-weight antibacterial agent, the antibacterial agent may fall off when the surface of the molded product is rubbed or wet, but the antibacterial agent seeps out again from the inside, In some cases, the effect lasts, and if the molded article is not used in an environment where it is rubbed or wet, it is possible to maintain the antibacterial properties for a long period of time.

The amount of the organic antibacterial agent to be added is preferably 0.01 to 2 parts by mass, more preferably 0.1 to 1 part by mass with respect to 100 parts by mass of the polypropylene resin composition.

(antifungal agent)
The polypropylene-based resin composition of the present embodiment may contain an antifungal agent. Antifungal agents include, but are not limited to, thiabendazole, carbendazine, captan, fluorofolpet, chlorothalonil, OBPA (10,10'-oxybis-10H-phenoxyarsine), methylsulfonyltetrachloropyridine, chloro methylisothiazoline, methylisothiazoline, diiodomethylparatolylsulfone, and the like.

Moreover, you may use the antibacterial agent mentioned above as an antifungal agent. Some antibacterial agents have an antifungal effect. In particular, components other than those commercially available as antifungal agents can also be used as antifungal agents.

Alternatively, copper powder may be directly added to the polypropylene-based resin composition, and the polypropylene-based resin composition and the copper powder may be kneaded to obtain a molded product. In this case, in order to obtain sufficient antibacterial and antifungal effects, the amount of copper powder added is preferably 5 to 60 parts by mass, more preferably 10 to 30 parts by mass, with respect to 100 parts by mass of the polypropylene resin composition. Department.

It is also possible to add a drug having an antiviral effect to the polypropylene-based resin composition to impart antiviral properties to the composition.

(other optional ingredients)
Dyes for coloring, pigments, antifoaming agents, plasticizers, lubricants, release agents, flame retardants, and the like can be given as other optional components that can be used in the present embodiment.

<Production of polypropylene resin composition>
Any method is adopted for the production of the polypropylene-based resin composition of the present embodiment. For example, a polypropylene resin (A), a copolymer (B) having a first block containing a hydrophilic polyether chain, a silicone compound (C), and any other additives (nucleating agents, surfactants, etc.) is sufficiently mixed using a premixing means such as a V-type blender, a Henschel mixer, a mechanochemical device, and an extrusion mixer, and then, if necessary, an extrusion granulator, a briquetting machine, or the like is used to form the premix. There is a method of granulating, then melt-kneading with a melt-kneader typified by a vented twin-screw extruder, and then pelletizing with a pelletizer.

In addition, there is a method of supplying each component independently to a melt kneader represented by a vented twin-screw extruder, or a method of premixing a part of each component and then supplying the rest of the components independently to a melt kneader. There are also methods of As a method of premixing a part of each component, for example, after premixing components other than the polypropylene resin (A) in advance, each component is mixed with the polypropylene resin (A), or A method of supplying each component directly can be mentioned.

As the extruder, it is preferable to use an extruder having a vent capable of degassing moisture in the raw material and volatile gas generated from the melt-kneaded resin. A vacuum pump is preferably installed from the vent for efficiently discharging generated moisture and volatile gas to the outside of the extruder. It is also possible to install a screen in front of the die portion of the extruder to remove foreign matters and the like mixed in the extruded raw material to remove the foreign matters from the resin composition. Such screens include wire meshes, screen changers, sintered metal plates (such as disk filters), and the like.

Examples of the melt-kneader include a twin-screw extruder, a Banbury mixer, a kneading roll, a single-screw extruder, and a multi-screw extruder with three or more screws.

The polypropylene-based resin composition extruded as described above is pelletized by direct cutting or by cutting a strand formed from an extruded product of the composition with a pelletizer. The shape of the pellet is preferably cylindrical. The diameter of such cylinders is preferably 1-5 mm, more preferably 2-3.3 mm. On the other hand, the length of the cylinder is preferably 1-30 mm, more preferably 2.5-3.5 mm.

Using the polypropylene-based resin composition of the present embodiment, various products can be produced by injection-molding the pellets produced as described above to obtain molded articles. Such injection molding includes not only ordinary molding methods, but also injection compression molding, injection press molding, gas-assisted injection molding, foam molding (including a method of injecting a supercritical fluid), insert molding, in-mold coating molding, heat insulation. Mold molding, rapid heating and cooling mold molding, two-color molding, sandwich molding, ultra-high speed injection molding, and the like can be mentioned. Moreover, as a method of molding, for example, either a cold runner method or a hot runner method can be selected.

Moreover, the polypropylene-based resin composition of the present embodiment can also be used in the form of various profile extrudates, sheets, films, and the like by extrusion molding. In addition, the inflation method, calendering method, casting method, and the like can be used for forming sheets and films. Furthermore, it is also possible to form a heat-shrinkable tube by applying a stretching operation. Further, the polypropylene-based resin composition of the present embodiment can be formed into a molded product by rotational molding, blow molding, or the like.

(Behavior of each component during molding)
In FIG. 1, each component (polypropylene resin (A) 1, a copolymer (B) having a first block containing a hydrophilic polyether chain at the time of molding (melt extrusion molding) of the polypropylene resin composition of Embodiment 1 2 and silicone compound (C) 3).

FIG. 1(a) shows a state in which the copolymer (B) 2 and the silicone compound (C) 3 are melted and uniformly mixed. The melt viscosity of the copolymer (B) during molding is lower than the melt viscosity of the polypropylene-based resin (A)1. Therefore, when subjected to a shearing force in the injection process during molding, the copolymer (B) 2 is first extruded to the tip of the flow (see FIG. 1(b)), and is present in many streaks on the surface layer. In this way, copolymer (B) 2 is concentrated on the surface of the molded article (see FIG. 1(c)).

The melt viscosity of the silicone compound (C) 3 during molding is also lower than that of the polypropylene-based resin (A) 1 . For this reason, similar to copolymer (B) 2, a surface concentrating effect occurs, and many are present on the surface. Furthermore, since the silicone compound (C) 3 has low compatibility with the polypropylene-based resin (A) 1, it is easily exposed on the surface of the molded product.

Thus, the copolymer (B) 2 tends to be located near the surface of the molded article, and the silicone compound (C) 3 tends to be located on the outermost surface of the molded article (see FIG. 1(c)).

The molecular weight of the silicone compound (C) is preferably 5,000 or more, more preferably 10,000 or more. The larger the molecular weight of the silicone compound (C), the more the silicone compound (C) is suppressed from detaching from the molded article, and the effect of suppressing the adhesion of dust (hydrophilic dust and hydrophobic dust) over a long period of time, and water-based stains and oil. Antifouling effect against system fouling lasts.

Further, when a polymer obtained by polymerizing silicone and polypropylene, such as silicone-graft-polymerized polypropylene, is used as the silicone compound (C), the polypropylene portion (resin portion 30) of the polymer is strongly bound to the resin (polypropylene-based resin). As a result, the silicone compound (C) is less likely to detach from the molded product, so that the effect of suppressing adhesion of dust and the antifouling effect against water-based and oil-based stains is maintained over a long period of time.

Embodiment 2.
A molded article according to the present embodiment is made of the polypropylene-based resin composition described above. The molded article according to the present embodiment is resistant to both hydrophilic dust stains and hydrophobic dust stains, and both water-based and oil-based liquid stains, by being made of the polypropylene-based resin composition. Has a staining effect.

FIG. 2 is a schematic cross-sectional view showing an example of a molded article according to Embodiment 2. FIG. In FIG. 2, a polypropylene resin composition containing a polypropylene resin (A) 1, a copolymer (B) 2 having a first block containing a hydrophilic polyether chain, and a silicone compound (C) 3, In the molded article, the desired arrangement state is shown for the copolymer (B) 2 and the silicone compound (C) 3.

Specifically, in FIG. 2(a), the copolymer (B) 2 is present in a layer near the surface of the molded article (surface layer) at a higher density than other sites, for example, 50% or more of the total copolymer (B) exists within a range from 1 nm to 50 μm in depth from the outermost surface (in the surface layer). On the other hand, the silicone compound (C) 3 and its silicone part are exposed on the outermost surface of the molded article.

FIGS. 2(b) and (c) show more desirable arrangement states of the silicone compound (C) 3. FIG. The resin portion 30 (see FIG. 2(b)) of the silicone compound (C) 3 is mixed with the polypropylene-based resin (A) 1 and integrated, and the silicone portion 31 is densely exposed on the outermost surface of the molded product. (See FIG. 2(c)).

In addition, when the copolymer (B) is exposed on the outermost surface in a large proportion, the hydrophilic portion may be exposed and water-based stains may easily adhere. However, since the copolymer (B) is present in large amounts near the surface of the molded article (for example, the depth from the outermost surface of the molded article is in the range of 1 nm to 50 μm), water-based stains are likely to adhere. can be avoided.

In addition, even if the copolymer (B) is present near the surface of the molded product, it may affect the outermost surface of the molded product, and the surface may become hydrophilic. However, since the silicone portion of the silicone compound (C) is exposed on the outermost surface, the outermost surface has both hydrophilic properties and hydrophobic properties.

Therefore, in the molded article according to this embodiment, it is preferable that the silicone part of the silicone compound is exposed on the surface. In particular, a structure such as that shown in FIG. 2(a) or FIG. In addition, the antifouling effect can be exhibited more remarkably against both water-based stains and oil-based stains.

The silicone concentration near the surface of the molded article is preferably higher than the silicone concentration inside the molded article. Here, the silicone concentration is the content of the silicone compound (C) in the polypropylene-based resin composition. Specifically, the silicone concentration in the range from the outermost surface of the molded product to a depth (depth from the outermost surface) of 10 nm higher than the silicone concentration in the deep part). The outermost surface of the molded product does not have to be the entire outermost surface of the molded product, and may be a part of the outermost surface.

Such a difference in silicone concentration in the depth direction of the molded product can be obtained by, for example, performing elemental analysis on the surface of the molded product using X-ray photoelectron spectroscopy, while sputtering the molded product with argon ions from the outermost surface side. It can be confirmed by a method of measuring the distribution of silicon concentration in the depth direction. The silicon concentration can be measured by measuring the silicon (Si) element concentration after confirming the Si—O bond. An example of measurement results is shown in FIG.

Embodiment 3.
A product according to the present embodiment includes the molded product described above. That is, the above-mentioned molded product is used, for example, as resin parts (internal parts, housings, etc.) of products such as home electric appliances and OA equipment. In the product of the present embodiment, by including the molded product described above, the effect of improving cleanliness and reducing the frequency of maintenance can be achieved.

Products include, for example, personal computers, notebook computers, CRT displays, printers, mobile terminals, mobile phones, copiers, fax machines, recording media (CD, CD-ROM, DVD, PD, FDD, etc.) drives, parabolic antennas, and power tools. , VTR, TV, iron, hair dryer, rice cooker, microwave oven, audio equipment, audio equipment (audio, laser disc (registered trademark), compact disc, etc.), lighting equipment (LED), remote control, ventilation fan, range hood, refrigerator , air conditioners (air conditioners, dehumidifiers, humidifiers, etc.), air purifiers, vacuum cleaners, rice cookers, cooking heaters, bath products, washroom products, jet towels, fans, typewriters, word processors, automobiles, vehicles Equipment (car navigation, car stereo, etc.), miscellaneous goods, and the like.

In addition, for example, if the above molded products are applied to resin parts such as air conditioners, doors, display devices, insulators, mirrors, measuring instruments, and operation parts of various devices, adhesion of dust dirt is reduced and cleanliness is improved. can be improved and maintenance frequency can be reduced. In particular, the molded article is useful as a resin part of a product that cannot be maintained for a long period of time by a user or a trader.

The molded article containing the above-described polypropylene-based resin composition of the present embodiment can be applied as long as the product has a resin part, and can be widely applied without being limited to the uses described above.

In addition, since the antifouling effect can be easily obtained only by molding, there is an advantage that there are overwhelmingly few complicated processes such as moving the molded product and coating work compared to painting or coating that has an antifouling effect. Therefore, the molded article containing the above-described polypropylene-based resin composition is suitable for mass production of products and has extremely high practicability. In addition, molded articles containing the above-mentioned polypropylene resin composition can be applied as exterior members without worrying about surface unevenness, rainbow patterns, glossiness, etc., compared to painting or coating with antifouling effects. Since it has the advantage of being easy to use, it is suitable for mass production of products and has extremely high practicality.

EXAMPLES The present invention will be described in more detail with reference to examples below, but the present invention is not limited to these examples.

[Examples 1 to 21, Comparative Examples 1 to 11]
For Examples 1-18 and Comparative Examples 1-11, components A, B and C were mixed in a blender in the proportions shown in Tables 1 and 3 below. In addition, for Examples 19 to 21, the ratios shown in Table 2 below were used for A component, B component, C component and nucleating agent (Example 19), or A component, B component, C component and nucleating agent. and surfactants (Examples 20, 21) or A component, B component, C component and inorganic filler (Examples 22, 23) were mixed in a blender. Each of the mixtures obtained above was melt-kneaded using Xplore series MC15 manufactured by DSM under conditions of a temperature of 200° C. and a screw rotation speed of 120 rpm.

From the melt-kneaded materials obtained in Examples 1 to 21 and Comparative Examples 1 to 11, square plates (molded products) with a size of 80 mm × 30 mm and a thickness of 2 mm were produced by injection molding using Xplore series IM12 manufactured by DSM. bottom.

Further, from the melt-kneaded materials obtained in Examples 1 to 21, a dumbbell test piece (molded article) specified in ISO527-2-1B was produced by injection molding using Xplore series IM12 manufactured by DSM.

The components A to C shown in Tables 1 to 3 are as follows.
[A component: polypropylene resin]
(A-1) Polypropylene (MA3H manufactured by Japan Polypropylene)
[Component B: a copolymer having a first block containing a hydrophilic polyether chain]
(B-1) A block (first block) derived from a hydrophilic polymer having a polyoxyethylene chain (hydrophilic polyether chain) and a block (second block) composed of polyester are repeatedly and alternately bonded. block copolymer (ADEKA STAB AS-301E, manufactured by ADEKA Co., Ltd.)
(B-2) A block (first block) derived from a hydrophilic polymer having a polyoxyethylene chain (hydrophilic polyether chain) and a block (second block) composed of polyolefin are repeatedly and alternately bonded. Block copolymer (Pelectron HS, Sanyo Chemical Industries Co., Ltd.)
[Component C: silicone compound]
(C-1) Silicone graft polymerization polypropylene (Rikeaid SG-170P, Riken Vitamin Co., Ltd.)
(C-2) Silicone graft polymerization polypropylene (BY-201, DuPont Toray Specialty Materials Co., Ltd.)
(C-3) Mixture of silicone resin and polypropylene (Crimbell CB-50PP, Fuji Chemical Co., Ltd.)
In Table 2, the nucleating agent is a mixture of polypropylene resin and nucleating agent (Rikemaster SN-003P, Riken Vitamin Co., Ltd.), and the surfactant is a mixture of polypropylene resin and nonionic surfactant (Rike Master PSR-345, Riken Vitamin Co., Ltd.).

<Evaluation method>
(1) The following measurements and evaluations (1-1) to (1-3) were performed on the obtained molded articles (square plates) of Examples 1 to 21 and Comparative Examples 1 to 11. Tables 1 and 2 show the results of measurement and evaluation.
(1-1) Evaluation of antifouling property against dust (hydrophilic dust and hydrophobic dust) After leaving the square plate in an environment of 23 ° C. and 50% humidity for 24 hours, a dust adhesion test was performed on the square plate. .

Antifouling properties were evaluated using Kanto loam (11 types of JIS test powder) as hydrophilic dust and carbon black (12 types of JIS test powder) as hydrophobic dust.

A method for attaching hydrophilic dust will be described. First, a certain amount (5 g) of Kanto loam is put into a mixer and stirred, and the surface of the molded product is exposed to the surface of the molded product, which is adhered to the surface of the molded product. After that, at an angle of 90° to the ground, from a height of 3 cm above the ground, it is brought into contact with the ground 5 times at a speed of 20 cm/sec to remove excess deposits.

Next, a method for adhering hydrophobic dust will be described. First, a certain amount (0.5 mL) of carbon black is sprinkled on the surface of the molded product through a sieve. After that, at an angle of 90° to the ground, from a height of 3 cm above the ground, it is brought into contact with the ground 5 times at a speed of 20 cm/sec to remove excess deposits.

The surface of the molded article to which hydrophilic dust or hydrophobic dust has adhered as described above is observed at a magnification of 100 times using a Nikon optical microscope Eclipse LV100ND, and the area of the molded article (80 mm × 30 mm) is binarized by image processing. ) to determine the ratio of the dust adhesion area.

The ratio of the measured dust adhesion area was evaluated based on the following criteria.
[Evaluation Criteria for Dust Adhesion]
Regarding the dust adhesion area ratio, if it is 3% or less, it is A (excellent antifouling property against dust), and if it is more than 3% and less than 9%, it is B (poor antifouling property against dust is better than A), A case of 9% or more is judged as C (insufficient antifouling property against dust).
(1-2) Evaluation of antifouling property against water-based fouling After leaving the square plate in an environment of 23 ° C. and 50% humidity for 24 hours, the contact angle of the square plate was measured to determine the antifouling property against water-based fouling. was evaluated.

The contact angle was measured using a contact angle measurement device DMo-501 manufactured by Kyowa Interface Science Co., Ltd. with a water droplet amount of 2 μL.

The contact angle measurement results were evaluated based on the following criteria.
[Evaluation criteria for antifouling property against water-based fouling]
A contact angle of 98° or more is judged as A (excellent antifouling property against water-based fouling), and a contact angle of less than 98° is judged as C (insufficient antifouling property against water-based fouling).
(1-3) Evaluation of antifouling property against oil-based dirt After the square plate was left in an environment of 23°C and 50% humidity for 24 hours, the square plate was subjected to an oil-based dirt adhesion test. Specifically, 50 μL of JIS_C9606 artificial contaminant was dripped on the surface of a square plate placed horizontally as an oil-based stain, spread over a 10 mm×25 mm square using a spatula, and left for 24 hours. After standing, the area of the artificially contaminated liquid was measured with a ruler, and the ratio to the area of the initially spread contaminated liquid (adhesion area of the contaminated liquid after 24 hours/area of the initially spread contaminated liquid) was obtained. .

The measurement result of the ratio of the surface area to which the artificial contaminant adhered was evaluated based on the following criteria.
[Evaluation Criteria for Adherence to Oil-Based Dirt]
It was expressed by the area ratio of the oil-based stain adhering to the square plate. Regarding the area ratio, when it is less than 50%, it is judged as A (especially excellent antifouling property against water-based fouling), and when it is 50% or more, it is judged as C (insufficient antifouling property against water-based fouling).
(2) Evaluation of creep properties (creep rupture strength test)
The obtained dumbbell test pieces of Examples 1 to 21 were pulled with a load of 15 MPa by a creep tester, and the displacement rate of the portion between the chucks holding the test pieces (inter-chuck distance) after starting to pull. The time until the test piece was elongated was measured so that ([(distance between chucks−initial distance between chucks)/initial distance between chucks]×100) was 6.4%. The measurement was performed with N=3, and the average value was obtained. In Table 2, this time (average value) is indicated as "creep characteristic (hour)" (unit: hr).

The measurement result of the time was evaluated based on the following criteria.
[Evaluation Criteria for Creep Property]
Regarding the measured time (average value), A is judged to be 30 hours or more, and C is judged to be less than 30 hours.

As for the creep properties, Table 2 below shows the results of Examples 19 to 21 only. However, the results of the creep rupture strength test of Examples 1 to 18 were all C judgments.

From the evaluation results shown in Tables 1 and 2, a polypropylene resin containing a polypropylene resin (A), a copolymer having a first block containing a hydrophilic polyether chain (B), and a silicone compound (C) It can be seen that Examples 1 to 21, which are molded articles of the composition, have an antifouling effect against all hydrophilic dust, hydrophobic dust, water-based stains, and oil-based stains.

On the other hand, when only component (B) is blended with component (A), and when only component (C) is blended with component (A) (Comparative Examples 1 to 11), Table 3 shows Thus, it was not possible to have sufficient antifouling effect against all hydrophilic dust, hydrophobic dust, water-based dirt and oil-based dirt.

In addition, in Examples 19 to 21, the creep property also satisfies the criteria, and it can be seen that the molded article of the present disclosure can be applied to parts and products subjected to stress.

It should be considered that the embodiments and examples disclosed this time are illustrative in all respects and not restrictive. The scope of the present disclosure is indicated by the scope of claims rather than the above description, and is intended to include all changes within the meaning and scope of equivalence to the scope of claims.

1 polypropylene-based resin (A), 2 copolymer (B) having a first block containing a hydrophilic polyether chain, 3 silicone compound (C), 30 resin portion, 31 silicone portion.

Claims (9)

a polypropylene-based resin (A);
a copolymer (B) having a first block comprising hydrophilic polyether chains;
a silicone compound (C);
contains
The molar ratio of oxygen to carbon in the elements constituting the hydrophilic polyether chain is 0.3 or more,
said copolymer (B) having alternating said first blocks and second blocks composed of polyester or polyolefin;
The silicone compound (C) is a silicone graft copolymer,
A polypropylene-based resin composition. a polypropylene-based resin (A);
a copolymer (B) having a first block comprising hydrophilic polyether chains;
a silicone compound (C);
a nucleating agent;
contains
The molar ratio of oxygen to carbon in the elements constituting the hydrophilic polyether chain is 0.3 or more,
said copolymer (B) having alternating said first blocks and second blocks composed of polyester or polyolefin;
The polypropylene-based resin composition, wherein the silicone compound (C) is at least one of a silicone graft copolymer and dimethylpolysiloxane. a polypropylene-based resin (A);
a copolymer (B) having a first block comprising hydrophilic polyether chains;
a silicone compound (C);
a surfactant;
contains
The molar ratio of oxygen to carbon in the elements constituting the hydrophilic polyether chain is 0.3 or more,
said copolymer (B) having alternating said first blocks and second blocks composed of polyester or polyolefin;
The polypropylene-based resin composition, wherein the silicone compound (C) is at least one of a silicone graft copolymer and dimethylpolysiloxane. a polypropylene-based resin (A);
a copolymer (B) having a first block comprising hydrophilic polyether chains;
a silicone compound (C);
contains
The molar ratio of oxygen to carbon in the elements constituting the hydrophilic polyether chain is 0.3 or more,
The copolymer (B) is a mixture of a copolymer of the first block and a second block composed of polyester and a copolymer of the first block and a second block composed of polyolefin,
The silicone compound (C) is a silicone graft copolymer or a high molecular weight silicone,
A polypropylene-based resin composition. 5. The polypropylene resin composition according to claim 1, further comprising a nucleating agent. 5. The polypropylene resin composition according to claim 1 , further comprising a surfactant. A molded article made of the polypropylene-based resin composition according to any one of claims 1 to 6 . The molded article according to claim 7 , wherein the silicone portion of the silicone compound (C) is exposed on the surface. A product comprising a molded article according to claim 7 or 8 .

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