WO2022196221A1 - Chemical foaming agent composition, chemical foaming agent master batch, foam and method for producing foam - Google Patents

Chemical foaming agent composition, chemical foaming agent master batch, foam and method for producing foam Download PDF

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Publication number
WO2022196221A1
WO2022196221A1 PCT/JP2022/005949 JP2022005949W WO2022196221A1 WO 2022196221 A1 WO2022196221 A1 WO 2022196221A1 JP 2022005949 W JP2022005949 W JP 2022005949W WO 2022196221 A1 WO2022196221 A1 WO 2022196221A1
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Prior art keywords
foam
resin
agent composition
foaming agent
chemical
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PCT/JP2022/005949
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French (fr)
Japanese (ja)
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賀文 今津
基 森
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コニカミノルタ株式会社
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Priority to JP2023506880A priority Critical patent/JPWO2022196221A1/ja
Publication of WO2022196221A1 publication Critical patent/WO2022196221A1/en

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    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
    • C08J9/00—Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof
    • C08J9/04—Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof using blowing gases generated by a previously added blowing agent
    • C08J9/06—Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof using blowing gases generated by a previously added blowing agent by a chemical blowing agent
    • C08J9/08—Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof using blowing gases generated by a previously added blowing agent by a chemical blowing agent developing carbon dioxide
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
    • C08K3/00—Use of inorganic substances as compounding ingredients
    • C08K3/01—Use of inorganic substances as compounding ingredients characterized by their specific function
    • C08K3/016—Flame-proofing or flame-retarding additives
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
    • C08L101/00—Compositions of unspecified macromolecular compounds
    • C08L101/12—Compositions of unspecified macromolecular compounds characterised by physical features, e.g. anisotropy, viscosity or electrical conductivity
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
    • C09K3/00—Materials not provided for elsewhere

Definitions

  • the present invention relates to a chemical foaming agent composition, a chemical foaming agent masterbatch, a foam, and a method for producing a foam. More specifically, the present invention provides a chemical foaming agent composition and a chemical foaming agent masterbatch that are capable of both miniaturizing cells and suppressing deterioration of flame retardancy when used for molding a foam, and furthermore, the chemical foaming agent composition.
  • the present invention relates to a foam produced by using a physical or chemical foaming agent masterbatch, in which both cell miniaturization and reduction in flame retardancy are suppressed, and a method for producing the same.
  • Injection foam molding is used to suppress sink marks (dents caused by molding shrinkage) and warpage in the molding of resin or elastomer foams used for exterior parts and structural parts used in automobiles and electrical appliances. things are increasing. In particular, for parts that are produced in small lots, if the chemical foaming method, which requires less equipment investment, is selected, the unit price of the product will be reduced, which is advantageous in terms of cost.
  • the chemical foaming method uses a chemical foaming agent that generates gas through thermal decomposition or chemical reaction.
  • foams obtained by the chemical foaming method had problems of deterioration in appearance quality and reduction in strength due to large internal cell diameters.
  • a technology has been developed to refine the air bubbles by adding a chemical foaming agent and a foaming aid to resins or elastomers.
  • “Chemical foaming agent” refers to a compound that generates gas (bubbles) by thermal decomposition or chemical reaction, among the chemicals used to obtain a foam by mixing with resin or the like.
  • “Chemical foaming agent composition” refers to a composition comprising a chemical foaming agent and an auxiliary agent other than the chemical foaming agent.
  • a “chemical blowing agent masterbatch” is a composition that combines a thermoplastic resin or thermoplastic elastomer with a chemical blowing agent or chemical blowing agent composition.
  • Patent Document 1 a foaming agent composition containing a citrate and a lithium compound (but excluding lithium salt) or zinc oxide is added to a thermally decomposable foaming agent to a thermoplastic resin to obtain fine particles.
  • a blowing agent composition that is foam molded with fine cells and a method for producing a thermoplastic resin foam are described.
  • Patent Document 2 discloses a foaming agent composition used for molding a resin foam, comprising sodium bicarbonate, which is a thermally decomposable foaming agent, lithium stearate, monosodium citrate, Blowing agent compositions are described that contain predetermined amounts of at least one of zinc, talc, and silica.
  • a foaming agent composition used for molding a resin foam comprising sodium bicarbonate, which is a thermally decomposable foaming agent, lithium stearate, monosodium citrate, Blowing agent compositions are described that contain predetermined amounts of at least one of zinc, talc, and silica.
  • by foam molding a resin using this foaming agent composition fine and uniform distribution of cells can be achieved, and appearance such as planar smoothness and substrate performance are improved. Excellent foams are said to be obtained.
  • the present invention has been made in view of the above-mentioned problems and circumstances, and the problem to be solved is a chemical foaming agent composition that can achieve both miniaturization of cells and suppression of deterioration in flame retardancy when used for molding foams. and to provide a chemical blowing agent masterbatch.
  • Another object of the present invention is to provide a foam produced using the above-mentioned chemical foaming agent composition or chemical foaming agent masterbatch, which achieves both miniaturization of cells and suppression of deterioration in flame retardancy, and a method for producing the same.
  • the present inventors selected sodium bicarbonate as a chemical foaming agent and selected a specific acidic substance as a foaming aid combined with it in the process of studying the causes of the above problems. It has been found that by using a chemical blowing agent composition, the foam obtained using the chemical blowing agent composition is a foam that achieves both miniaturization of cells and suppression of deterioration in flame retardancy. reached. That is, the above problems related to the present invention are solved by the following means.
  • a foaming material containing the chemical blowing agent composition according to any one of items 1 to 3 or the chemical blowing agent masterbatch according to item 4, and a thermoplastic resin or thermoplastic elastomer A foam molded by foaming.
  • thermoplastic resin or thermoplastic elastomer contains at least one selected from polyolefin resins, acrylonitrile-butadiene-styrene resins, polystyrene resins, polyamide resins, polyvinyl chloride resins, ethylene vinyl acetate resins and thermoplastic elastomers.
  • a foaming material is produced by mixing the chemical blowing agent composition according to any one of items 1 to 3 or the chemical blowing agent masterbatch according to item 4 with a thermoplastic resin or a thermoplastic elastomer. and foam-molding the foam material with an injection molding machine.
  • the inventors of the present invention have investigated inorganic compounds from the viewpoint of suppressing the deterioration of the flame retardancy of the obtained foam, and found that, among inorganic compounds, acidic substances in particular suppress the deterioration of the flame retardancy of the foam.
  • acidic substances in particular suppress the deterioration of the flame retardancy of the foam.
  • sodium bicarbonate is also excellent in the ability to make air bubbles fine.
  • the inventors have found that even if an organic compound is used, an acidic substance having a melting point of 400° C. or higher can provide the same effect as an inorganic acidic substance.
  • sodium bicarbonate causes the chemical reaction represented by the above acidic substance and formula (2) to generate bubbles (CO 2 gas).
  • the decomposition temperature of sodium hydrogen carbonate is 270°C, but it is known that the decomposition reaction of formula (1) occurs gradually from about 50°C.
  • the chemical reaction of formula (2) is believed to occur at a lower temperature than the reaction of formula (1).
  • sodium bicarbonate generates bubbles ( CO2 gas) at a lower temperature when it reacts with an acidic substance as in equation (2).
  • foaming occurs at such a low temperature, the viscosity of the matrix such as resin or elastomer is in a state of high viscosity, so it is difficult for the foamed gas bubbles to coalesce.
  • the chemical blowing agent composition of the present invention is a chemical blowing agent composition containing sodium hydrogencarbonate and an acidic substance, wherein the acidic substance is an inorganic compound or an organic compound having a melting point of 400° C. or higher. and This feature is a technical feature common to each embodiment of the chemical blowing agent composition below.
  • the chemical blowing agent composition may contain an organic compound having a melting point of less than 400°C. It is preferable that the content of the organic compound having a melting point of less than 400° C. is within a range of 58% by mass or less with respect to the total amount of the foaming agent composition.
  • the acidic substance is at least one selected from boric acid, diboron trioxide, sodium dihydrogen phosphate and sodium hydrogen sulfite. It preferably contains seeds.
  • the chemical blowing agent masterbatch of the present invention contains the chemical blowing agent composition of the present invention and a thermoplastic resin or thermoplastic elastomer.
  • the foam of the present invention is obtained by foam-molding a foam material containing the chemical foaming agent composition of the present invention or the chemical foaming agent masterbatch of the present invention and a thermoplastic resin or thermoplastic elastomer. is.
  • the content of the organic compound derived from the chemical foaming agent composition and having a melting point of less than 400° C. relative to the total amount of the foam is 1% by mass or less. is preferably within the range of
  • the thermoplastic resin or thermoplastic elastomer is polyolefin resin, acrylonitrile-butadiene-styrene resin, polystyrene resin, polyamide resin, polyvinyl chloride resin. , ethylene vinyl acetate resin and thermoplastic elastomer.
  • the foam may further contain a flame retardant from the viewpoint of exhibiting the effects of the present invention.
  • the method for producing the foam of the present invention comprises the step of mixing the chemical foaming agent composition of the present invention or the chemical foaming agent masterbatch of the present invention with a thermoplastic resin or thermoplastic elastomer to obtain a foam material; and a step of foam-molding the material with an injection molding machine.
  • the ratio of the chemical foaming agent composition to the total amount of the thermoplastic resin or thermoplastic elastomer in the foam material is 0.1 to 1. It is preferably in the range of 0.7% by weight.
  • the chemical blowing agent composition of the present invention is a chemical blowing agent composition containing sodium hydrogencarbonate and an acidic substance, wherein the acidic substance is an inorganic compound or an organic compound having a melting point of 400° C. or higher. and As described above, the chemical foaming agent composition is a composition comprising a chemical foaming agent and an auxiliary agent that is a component other than the chemical foaming agent. Auxiliaries include foaming aids, anti-drip agents, antioxidants, lubricants, dispersants, nucleating agents, and the like.
  • the chemical foaming agent composition of the present invention contains sodium hydrogen carbonate as a chemical foaming agent and the acidic substance as an auxiliary agent (foaming auxiliary agent).
  • Sodium bicarbonate is used as a chemical blowing agent in the chemical blowing agent composition of the present invention.
  • Sodium bicarbonate decomposes as in the above formula (1) or formula (2) to generate CO 2 gas, for example, thermoplastic resin or thermoplastic elastomer (hereinafter sometimes referred to as "resin etc.”). form air bubbles within the matrix of
  • the chemical blowing agent composition of the present invention is used to form foams.
  • the foam is composed of a matrix containing a resin or the like as a main component and cells.
  • the acidic substance contained in the chemical foaming agent composition of the present invention (hereinafter referred to as "acidic substance A”) is an inorganic compound or an organic compound having a melting point of 400°C or higher.
  • the acidic substance according to the present invention also includes a substance (for example, diboron trioxide) that generates an acid capable of dissociating protons H 3 + in the coexistence of water or an aqueous medium.
  • the acidic substance A functions as a foaming aid that aids foaming of the chemical foaming agent, sodium hydrogen carbonate.
  • an acidic substance that is an inorganic compound is also referred to as “acidic substance A1”, and an acidic substance that is an organic compound having a melting point of 400° C. or higher is also referred to as “acidic substance A2”.
  • the acidic substance A functions to cause the CO 2 gas generated from sodium hydrogen carbonate to exist as fine bubbles in a matrix such as a resin.
  • the acidic substance A preferably has a property of improving the flame retardancy without causing deterioration of the flame retardancy of the resin constituting the matrix of the foam. The method for evaluating the cell diameter and flame retardancy of the foam will be described later.
  • the chemical foaming agent composition of the present invention may contain optional components other than sodium hydrogen carbonate and acidic substance A within a range that does not impair the effects of the present invention.
  • optional components include chemical foaming agents other than sodium hydrogencarbonate, foaming aids other than acidic substance A, anti-drip agents, antioxidants, lubricants, dispersants, and nucleating agents.
  • the content of the organic compound having a melting point of less than 400° C. may be 58% by mass or less with respect to the total amount of the chemical blowing agent composition. It is preferably 22% by mass or less, more preferably 22% by mass or less. It is particularly preferred that the chemical blowing agent composition of the present invention does not contain organic compounds with a melting point of less than 400°C.
  • composition of chemical foaming agent composition contains sodium bicarbonate and acidic substance A. Furthermore, optional components may be contained within the above ranges. Each component contained in the chemical foaming agent composition of the present invention will be described below.
  • sodium hydrogen carbonate is a chemical foaming agent that is solid (typically powdery) at room temperature (25° C.), and thermally decomposes as a single unit of sodium hydrogen carbonate as shown in formula (1). Decomposition of sodium bicarbonate according to formula (1) is said to begin gradually at 50°C.
  • sodium hydrogen carbonate reacts with acidic substance A according to formula (2).
  • the reaction temperature is not particularly fixed, cells can be generated simply by adding to the thermoplastic resin or thermoplastic elastomer that mainly constitutes the matrix of the foam and performing molding.
  • the acidic substance A is typically solid at room temperature (25° C.) and preferably powder.
  • the acidic substance A can dissociate protons H + in the presence of water or an aqueous medium. It is a pH of an aqueous solution of the substance measured at a temperature of 23° C.) is less than 7.0.
  • the pH of the acidic substance A is preferably 4.6 or less, more preferably in the range of 2.1 to 4.6, from the viewpoint of miniaturization of cells when formed into a foam.
  • the particle shape and average particle size of the acidic substance A are preferably the same as those of sodium hydrogen carbonate used together, for example.
  • Examples of the acidic substance A1 include solid acids or acid salts such as boric acid, its anhydrides, borates, phosphates, sulfites, and acidic metal oxides.
  • As the acidic substance A among these, one or more selected from boric acid, diboron trioxide, sodium dihydrogen phosphate and sodium hydrogen sulfite are preferable.
  • the content ratio of sodium hydrogen carbonate and acidic substance A in the chemical blowing agent composition is 100% by mass for the total of sodium hydrogen carbonate and acidic substance A. It is preferably in the range of 5 to 90 mass %, and the acidic substance A is in the range of 95 to 10 mass %. More preferably, sodium hydrogen carbonate is in the range of 10 to 85% by mass, and acidic substance A is in the range of 90 to 15% by mass. More preferably, sodium hydrogen carbonate is in the range of 15 to 80% by mass, and acidic substance A is in the range of 85 to 20% by mass.
  • the chemical foaming agent composition may contain other chemical foaming agents other than sodium hydrogencarbonate as optional components within a range that does not impair the effects of the present invention.
  • Other chemical blowing agents specifically include azodicarbonamide (ADCA), P,P'-oxybis(benzenesulfonylhydrazide) (OBSH), N,N'-dinitrosopentamethylenetetramine, 5-phenyl-1 , 2,3,4-tetrazole and organic acid metal salts.
  • organic chemical blowing agents having a melting point of less than 400°C are It is preferable that the total content of organic compounds (hereinafter also referred to as “low-melting-point organic compounds”) is 58% by mass or less. More preferably, the chemical blowing agent composition does not contain low-melting organic chemical blowing agents, and particularly preferably does not contain other chemical blowing agents.
  • the chemical foaming agent composition may contain optional components, such as auxiliary agents other than acidic substance A, foaming assistants other than acidic substance A, anti-drip agents, antioxidants, lubricants, etc. , dispersants, nucleating agents and the like.
  • auxiliary agents include inorganic compounds that are not acidic substances, such as talc, calcium carbonate, lithium carbonate, and lithium borate.
  • organic acidic compounds with a melting point of less than 400°C such as citric acid and monosodium citrate, and non-acidic organic compounds such as lithium stearate, lithium acetate, lithium oxalate, lithium citrate, sodium oxalate and sodium benzoate. compound.
  • the total content of low-melting organic compounds in the chemical foaming agent composition It is preferably contained in an amount of 58% by mass or less. More preferably, the chemical blowing agent composition does not contain a low-melting organic blowing aid, and particularly preferably does not contain other aids.
  • the compounds described as specific examples of anti-drip agents, antioxidants, lubricants, etc. in the later-described foaming material can be used as specific examples of other auxiliary agents in the chemical foaming agent composition.
  • the chemical blowing agent composition contains aids other than these blowing aids, the total content of low-melting organic compounds in the chemical blowing agent composition should be 58% by mass or less. is preferred. It is more preferable that the chemical blowing agent composition does not contain low-melting-point organic compounds among aids other than these foaming aids, and particularly preferably does not contain aids other than these foaming aids.
  • the chemical foaming agent composition of the present invention preferably does not contain components other than sodium hydrogen carbonate and acidic substance A. That is, the chemical foaming agent composition of the present invention preferably comprises sodium hydrogen carbonate and acidic substance A.
  • the chemical blowing agent composition of the present invention may be in the form of a mixture of sodium bicarbonate and acidic substance A, or a mixture of these essential ingredients and optional ingredients.
  • the sodium hydrogen carbonate and the acidic substance A are prepared separately, or when optional ingredients are used in addition to these essential ingredients, the optional ingredients are further prepared.
  • it may be in the form of a two-component or multi-component type composition in which each component prepared separately is used in combination at the time of use.
  • the chemical foaming agent masterbatch of the present invention is characterized by containing the chemical foaming agent composition of the present invention and a thermoplastic resin or thermoplastic elastomer (resin or the like).
  • a foam material is produced by directly blending the chemical foaming agent composition into a resin or the like that mainly constitutes the matrix of the foam. , a method of foam-molding the foam material to form a foam.
  • the foam material may be produced by blending the chemical foaming agent masterbatch of the present invention with a resin or the like.
  • the chemical foaming agent masterbatch of the present invention By using the chemical foaming agent masterbatch of the present invention, uniform mixing with enhanced dispersibility of the chemical foaming agent composition in the resin or the like can be facilitated. By uniformly dispersing the chemical foaming agent composition, bonding of cells can be suppressed, and the cell diameter can be made finer.
  • the resin or the like contained in the chemical foaming agent masterbatch of the present invention can be part of the resin or the like contained in the foaming material in the foam to be described later.
  • the sum of the resin etc. derived from the chemical foaming agent masterbatch and the resin etc. added later in the foaming material is the resin etc. which mainly constitutes the matrix of the foam. .
  • X [mass%] is, for example, preferably 1 to 5% by mass, more preferably 2 to 4% by mass.
  • the content of the chemical foaming agent composition in the chemical foaming agent masterbatch of the present invention can be calculated from the content of the chemical foaming agent composition with respect to the total amount of resins and the like in the foaming material described later.
  • the content of the chemical foaming agent composition with respect to the total amount of resin etc. in the foaming material is Y [% by mass]
  • the content of the chemical foaming agent composition in the chemical foaming agent masterbatch is, with respect to the total amount of resin etc. Y/(X/100) [% by mass].
  • the resins, etc. that mainly constitute the matrix of the foam, the resins, etc. in the chemical foaming agent masterbatch and the resins, etc. added later may be the same or different.
  • the chemical foaming agent masterbatch of the present invention may further contain other additives as necessary.
  • specific examples of other additives include the same specific examples as the additives in the foamed material described later.
  • the method for producing the chemical blowing agent masterbatch of the present invention is not particularly limited.
  • the mixture thus obtained is used as a chemical foaming agent masterbatch.
  • a method of melting and kneading the mixture obtained above to form a chemical foaming agent masterbatch may be used.
  • the following operations may be performed to suppress the decomposition of sodium hydrogencarbonate and the reaction between sodium hydrogencarbonate and the acidic substance A as much as possible, that is, to suppress foaming.
  • the operations include applying pressure to the melt-kneaded material, setting the temperature of the melt-kneaded material to a low temperature, and cooling the melt-kneaded material immediately after melt-kneading.
  • the foam of the present invention is obtained by foam-molding a foam material containing the chemical foaming agent composition of the present invention or the chemical foaming agent masterbatch of the present invention and a thermoplastic resin or thermoplastic elastomer. is.
  • a “foaming material” is a composition in which a thermoplastic resin or thermoplastic elastomer is mixed with a chemical foaming agent, a chemical foaming agent composition, or a chemical foaming masterbatch.
  • a “foam” is a molded article obtained by foam-molding a composition obtained by mixing a thermoplastic resin or thermoplastic elastomer with a chemical foaming agent, a chemical foaming agent composition, or a chemical foaming agent masterbatch into a predetermined shape. It may also be said that it is a molded product obtained by foam-molding a foam material into a predetermined shape.
  • the foaming material according to the present invention is a composition containing the chemical foaming agent composition of the present invention or the chemical foaming agent masterbatch of the present invention and a thermoplastic resin or thermoplastic elastomer.
  • the foam of the present invention is a molded article obtained by foam-molding the foam material of the present invention into a predetermined shape.
  • the foaming material for obtaining the foam of the present invention contains the chemical foaming agent composition of the present invention or the chemical foaming agent masterbatch of the present invention and a thermoplastic resin or thermoplastic elastomer (resin or the like).
  • the foam material may be produced by directly blending the chemical foaming agent composition into the resin or the like that mainly constitutes the matrix of the foam of the present invention. It may be produced by compounding.
  • the chemical foaming agent masterbatch of the present invention is used for the foaming material, the resins and the like contained in the foaming material are the sum of the resins and the like contained in the chemical foaming agent masterbatch of the present invention and the resins and the like added later.
  • any thermoplastic resin or thermoplastic elastomer normally used for foam molding can be used without particular limitation. That is, according to the foam of the present invention, by using the chemical foaming agent composition of the present invention, it is possible to miniaturize cells and suppress deterioration of flame retardancy due to the effects described above. Therefore, according to the foam of the present invention, by using the chemical blowing agent composition of the present invention, it is possible to use any kind of thermoplastic resin and thermoplastic elastomer regardless of the kind of thermoplastic resin and thermoplastic elastomer. Similarly, microbubbles can be made finer and flame retardancy can be suppressed.
  • thermoplastic resin or thermoplastic elastomer contained in the foam material is not particularly limited, but polyolefin resin, acrylonitrile-butadiene-styrene resin (ABS resin), polystyrene resin, polyamide resin, polychlorinated It preferably contains at least one selected from vinyl resins, ethylene vinyl acetate resins and thermoplastic elastomers.
  • ABS resin acrylonitrile-butadiene-styrene resin
  • polystyrene resin polyamide resin
  • polychlorinated It preferably contains at least one selected from vinyl resins, ethylene vinyl acetate resins and thermoplastic elastomers.
  • thermoplastic resin examples include polyolefin resins, polystyrene resins, polyamide resins, polyimide resins, polyester resins, acrylic resins, polyurethane resins, polyvinyl chloride resins, vinyl acetate resins, ethylene vinyl acetate resins, epoxy resins, and phenol resins.
  • melamine resin polycarbonate resin, polyacetal resin, polyphenylene ether resin, polyphenylene sulfide resin, polysulfone resin, styrene-acrylonitrile resin (AS resin), styrene-(meth)acrylic acid resin, styrene-methyl methacrylate resin, acrylonitrile-butadiene -Styrene resin (ABS resin), methyl methacrylate-butadiene-styrene resin (MBS resin), and the like.
  • AS resin styrene-acrylonitrile resin
  • ABS resin acrylonitrile-butadiene -Styrene resin
  • MFS resin methyl methacrylate-butadiene-styrene resin
  • thermoplastic resins used for the foam of the present invention.
  • Polyolefin resins are homopolymers or copolymers polymerized with olefin as the main monomer component.
  • olefin means the aliphatic chain type unsaturated hydrocarbon which has one double bond.
  • the main component that constitutes the resin refers to a component that accounts for 50% by mass or more of the total monomer components that constitute the polymer.
  • the polyolefin resin is a homopolymer or copolymer containing olefin in an amount of preferably 60 to 100% by mass, more preferably 70 to 100% by mass, and still more preferably 80 to 100% by mass in the total monomer components. .
  • Olefin copolymers include copolymers of olefins with other olefins, or copolymers of olefins with other monomers that can be copolymerized with olefins.
  • the content of the other monomers in the polyolefin resin is preferably 30% by mass or less, more preferably 0 to 20% by mass, based on the total monomer components.
  • an ⁇ -olefin having 2 to 12 carbon atoms is preferable.
  • examples of olefins include ethylene, propylene, 1-butene, isobutene, 1-pentene, 3-methyl-1-butene, 1-hexene, 1-octene, and 1-decene.
  • the olefins may be used singly or in combination of two or more.
  • Examples of other monomers copolymerizable with olefins include cyclic olefins such as cyclopentene and norbornene, and dienes such as 1,4-hexadiene and 5-ethylidene-2-norbornene. Furthermore, monomers such as vinyl acetate, styrene, (meth)acrylic acid and its derivatives, vinyl ether, maleic anhydride, carbon monoxide, and N-vinylcarbazole may be used. These other monomers may be used singly or in combination of two or more in the polymerization of the polyolefin resin.
  • “(meth)acrylic acid” means at least one of acrylic acid and methacrylic acid.
  • polyolefin resins include polyethylene resins containing ethylene as a main component, such as high-density polyethylene (HDPE), low-density polyethylene (LDPE), and linear low-density polyethylene (LLDPE); polypropylene (propylene homopolymer); , ethylene-propylene copolymers, propylene-butene copolymers, ethylene-propylene-butene copolymers, and ethylene-propylene-diene copolymers.
  • HDPE high-density polyethylene
  • LDPE low-density polyethylene
  • LLDPE linear low-density polyethylene
  • polypropylene propylene homopolymer
  • ethylene-propylene copolymers propylene-butene copolymers
  • ethylene-propylene-butene copolymers ethylene-propylene-butene copolymers
  • ethylene-propylene-diene copolymers ethylene-propylene-diene
  • polyethylene resin and polypropylene resin are preferable, and polypropylene resin is more preferable.
  • the stereoregularity of the structure derived from propylene in the polypropylene resin may be isotactic, syndiotactic, or atactic.
  • Polypropylene is more preferable as the polypropylene resin.
  • a polystyrene resin is a homopolymer or copolymer polymerized with a styrene-based monomer as the main monomer component.
  • Styrenic monomers include, for example, styrene, ⁇ -methylstyrene, vinyltoluene, chlorostyrene, ethylstyrene, i-propylstyrene, dimethylstyrene, bromostyrene and the like.
  • polystyrene resin a polystyrene resin containing styrene as a main component, that is, containing 50% by mass or more of styrene is preferable, and polystyrene (styrene homopolymer) is more preferable.
  • the polystyrene resin may be a copolymer of a styrene-based monomer and a vinyl monomer copolymerizable with the styrene-based monomer, the main component of which is a styrene-based monomer.
  • vinyl monomers examples include alkyl (meth)acrylates such as methyl (meth)acrylate, ethyl (meth)acrylate, butyl (meth)acrylate, and cetyl (meth)acrylate; (meth)acrylonitrile; ate, dimethyl fumarate, diethyl fumarate, ethyl fumarate, divinylbenzene, alkylene glycol dimethacrylate, and other bifunctional monomers.
  • ABS resin acrylonitrile-butadiene-styrene resin
  • BR polybutadiene
  • SBR styrene-butadiene copolymer
  • ABS resin can also be produced by a blending method in which rubber and AS resin are mechanically mixed.
  • An ABS resin obtained by a graft-blending method of mixing a polymer and an AS resin is preferred.
  • ABS resin for example, part of styrene can be replaced with ⁇ -methylstyrene for the purpose of improving heat resistance.
  • ABS resins it is also possible to introduce methyl methacrylate into the AS resin phase.
  • Polyamide resins include, for example, aliphatic, aromatic, and aliphatic-aromatic polyamide homopolymers, aliphatic and aromatic polyamide copolymers, and mixtures thereof.
  • Polyamide homopolymers specifically include polyhexamethyleneadipamide (polyamide 66), polyhexamethyleneazelaamide (polyamide 69), polyhexamethylenesebacamide (polyamide 610), polyhexamethylenedodecanediamide (polyamide 612), polytetramethylene adipamide (polyamide 46), polydodecanmethylenedodecanamide (polyamide 1212), polycyclamide Q2 (polyamide C8), and the like.
  • Polyamide homopolymers further include lactams such as polycaprolactam (polyamide 6), polylaurolactam (polyamide 12), poly-11-aminoundecanoic acid (polyamide 11) and di(p-aminocyclohexyl)methandodecanediamide.
  • lactams such as polycaprolactam (polyamide 6), polylaurolactam (polyamide 12), poly-11-aminoundecanoic acid (polyamide 11) and di(p-aminocyclohexyl)methandodecanediamide.
  • Polyamides and the like prepared by ring opening are included.
  • polyxylylene adipamide polyamide MXD6
  • polytrimethylhexamethylene terephthalamide polyamide 6-3-T
  • polyhexamethylenediamine terephthalamide polyamide 6T
  • polyhexamethylene isophthalamide polyamide 6I
  • Aliphatic and aromatic polyamide copolymers include polyamides prepared by copolymerization of at least two of the above polymers or their constituents. Specific examples of these copolymers include polyamide 6/66 copolymer, polyamide 6/12 copolymer, polyamide 6/6T copolymer, and polyamide 6I/6T copolymer.
  • thermoplastic resin used for the foam of the present invention one of the thermoplastic resins listed above may be used alone, or two or more of them may be used in combination.
  • a polystyrene resin may be used as a main component, and a combination of the polystyrene resin and other resins may be used.
  • other resins in that case, polyethylene resins, polypropylene resins, acrylic resins, AS resins, ABS resins and the like are preferable.
  • thermoplastic elastomer are polymers or polymer blends that have properties similar to vulcanized rubber at the temperature of use, but can be molded and remolded like thermoplastics at elevated temperatures. It consists of In the present invention, thermoplastic elastomers are preferred as resins and the like, as with polyolefin resins, ABS resins, polystyrene resins, polyamide resins, polyvinyl chloride resins, and ethylene vinyl acetate resins in the above thermoplastic resins.
  • Thermoplastic elastomers contain both a flexible component (rubber phase or soft segment) and a molecularly constrained component (resin phase or hard segment) within the material.
  • the chemical composition and structure of various raw rubbers can be adopted for the soft segment, and various resin components are applied for the hard segment.
  • Thermoplastic elastomers are generally classified according to the chemical composition of the hard segments.
  • Thermoplastic elastomers classified in this way include styrene elastomers, chlorinated polyethylene, vinyl chloride elastomers, olefin elastomers, urethane elastomers, ester elastomers, amide elastomers, and ionomers.
  • Styrenic elastomers include block copolymers of styrene and butadiene or isoprene (SBS or SIS) and their hydrogenated (hydrogenated) polymers (SEBS or SEPS).
  • SBS styrene-based elastomers
  • diene-based rubber-like polymers such as polybutadiene (BR), styrene-butadiene copolymer (SBR), and ethylene-propylene-nonconjugated diene three-dimensional copolymer are added to polystyrene resin. and high impact polystyrene (HIPS).
  • PVC-based elastomers examples include a blend of polyvinyl chloride (PVC) with a high degree of polymerization and a plasticizer, a blend of partially crosslinked PVC to which a crosslinked structure is imparted during PVC synthesis and plasticized PVC, and PVC and acrylonitrile-butadiene rubber (NBR). and blended products with urethane rubber.
  • PVC polyvinyl chloride
  • NBR acrylonitrile-butadiene rubber
  • the olefinic elastomers include polyolefins, preferably polypropylene, and rubbers such as ethylene-propylene rubber (EPM), ethylene-propylene-diene rubber (EPDM), isobutylene-isoprene rubber (IIR), natural rubber (NR), NBR and the like.
  • EPM ethylene-propylene rubber
  • EPDM ethylene-propylene-diene rubber
  • IIR isobutylene-isoprene rubber
  • NR natural rubber
  • NBR NBR
  • a dynamic vulcanization type in which crosslinked rubber particles are finely dispersed in polyolefin by vulcanizing rubber when mixing polyolefin and rubber.
  • urethane-based elastomer a block copolymer in which the hard segment is polyurethane and the soft segment is aliphatic polyether or polyester can be applied.
  • ester-based elastomer a block copolymer having an aromatic polyester hard segment and an aliphatic polyether or polyester soft segment can be applied.
  • amide elastomer a block copolymer having an aliphatic polyamide (mainly polyamide 12 and 11) as the hard segment and an aliphatic polyether or polyester as the soft segment can be applied.
  • thermoplastic resin or thermoplastic elastomer contained in the foamed material of the present invention one selected from the above thermoplastic resins and thermoplastic elastomers may be used alone, or two or more thereof may be used in combination.
  • the foaming material according to the present invention contains the chemical foaming agent composition of the present invention in the range of 0.1 to 1.7% by mass with respect to the total amount of the thermoplastic resin and thermoplastic elastomer (resin etc.) in the foaming material. is preferably contained in the range of 0.2 to 0.5% by mass.
  • the content of the organic compound having a melting point of less than 400° C. derived from the chemical foaming agent composition, relative to the total amount of the foaming material, is preferably within the range of 1% by mass or less, and is 0.3% by mass or less. is more preferable, and it is particularly preferable that it is 0% by mass, that is, it does not contain.
  • the content of the organic compound having a melting point of less than 400° C. derived from the chemical foaming agent composition is 1% by mass or less, further 0.3% by mass.
  • it can be set to 0 mass % especially.
  • by using a chemical foaming agent composition to form a foam from a resin or the like that does not contain a chemical foaming agent composition it is difficult to A decrease in combustibility can be suppressed.
  • the foam material according to the present invention preferably contains a flame retardant as an optional component depending on the type of thermoplastic resin or thermoplastic elastomer. Whether or not to add a flame retardant to the foam material is appropriately selected, for example, in the evaluation of flame retardancy described later, using the burning time of the resin or the like as an index. Examples of resins having flame retardancy without the addition of flame retardants include polyamide resins.
  • flame retardants examples include brominated flame retardants, phosphorus flame retardants, and inorganic flame retardants such as antimony compounds and metal hydroxides.
  • a flame retardant may be used individually by 1 type, and may use 2 or more types together.
  • Brominated flame retardants include tetrabromobisphenol A (TBBA), decabromodiphenyl ether (Deca-BDE), tribromophenol, hexabromocyclododecane (HBCD), ethylenebis(tetrabromophthalimide), TBBA carbonate oligomer, TBBA Epoxy oligomers, brominated polystyrene, bis(pentabromophenyl)ethane, TBBA-bis(dibromopropyl ether), poly(dibromophenol), hexabromobenzene (HBB), and the like.
  • TBBA tetrabromobisphenol A
  • Deca-BDE decabromodiphenyl ether
  • HBCD hexabromocyclododecane
  • ethylenebis(tetrabromophthalimide) ethylenebis(tetrabromophthalimide
  • brominated flame retardant bis(hydroxyphenyl)sulfone derivatives, bis(alkoxyphenyl)sulfone derivatives, etc. may be used. Specific examples include bis[3,5-dibromo-4-(2,3-dibromopropoxy)phenyl]sulfone.
  • non-drip type brominated flame retardants that prevent resin from dripping during combustion include, for example, bis(pentabromophenyl)ethane.
  • an anti-drip agent which will be described later, may be used in combination.
  • the phosphorus-based flame retardant may be an organic phosphorus-based flame retardant or an inorganic phosphorus-based flame retardant.
  • Organic phosphorus flame retardants include, for example, organic phosphoric acid esters.
  • organic phosphates include phosphate compounds such as phosphites, phosphates and phosphonates. Among these, it is particularly preferable to use phosphates.
  • the inorganic phosphorus-based flame retardant a high-molecular-weight inorganic phosphorus-based compound is preferable, and examples thereof include ammonium polyphosphate and derivatives thereof.
  • phosphites include triphenylphosphite, tris(nonylphenyl)phosphite, tris(2,4-di-t-butylphenyl)phosphite, distearylpentaerythritol diphosphite, bis(2 ,6-di-t-butyl-4-methylphenyl)pentaerythritol diphosphite, bis(2,4-di-t-butylphenyl)pentaerythritol diphosphite and the like.
  • phosphate esters include triphenyl phosphate, tris(nonylphenyl) phosphate, tris(2,4-di-t-butylphenyl) phosphate, distearylpentaerythritol diphosphate, bis(2,6-di- t-butyl-4-methylphenyl)pentaerythritol diphosphate, bis(2,4-di-t-butylphenyl)pentaerythritol diphosphate, tributyl phosphate, bisphenol A bis-diphenyl phosphate, aromatic condensed phosphate ester, etc. mentioned.
  • aromatic condensed phosphate esters examples include 1,3-phenylene bis(di-2,6 xylenyl phosphate), bisphenol A bis(diphenyl phosphate) and 1,3-phenylene bis(diphenyl phosphate).
  • phosphonate examples include dimethyl benzenephosphonate and benzenephosphonate.
  • the content of the flame retardant in the foamed material according to the present invention is preferably in the range of 1 to 30% by mass with respect to the total amount of the resin and the like.
  • the content of the flame retardant in the foam material is within the above range, the resulting foam has good flame retardancy and foam moldability is likely to be ensured. More preferably, the content of the flame retardant is in the range of 1 to 25% by mass with respect to the total amount of the resin and the like.
  • the foaming material according to the present invention contains a resin or the like and the chemical foaming agent composition of the present invention as essential components, and further contains a flame retardant as an optional component.
  • the foam material according to the present invention may contain additives other than the flame retardant as long as the effects of the present invention are not impaired.
  • known additives generally added to foams can be applied.
  • Other additives include anti-drip agents, antioxidants, lubricants, hindered amine compounds, ultraviolet absorbers, antistatic agents, fluorescent whitening agents, pigments, dyes, and the like.
  • Anti-drip agents are added for the purpose of preventing dripping of resin materials during combustion and improving flame retardancy. silicates and the like.
  • An anti-drip agent may be used individually by 1 type, or may be used in combination of 2 or more types.
  • Antioxidants include hindered phenol antioxidants, phosphite ester antioxidants, or a mixture of both.
  • Lubricants include fatty acid salts, fatty acid amides, silane polymers, solid paraffin, liquid paraffin, calcium stearate, zinc stearate, stearamide, silicone powder, methylene bis stearamide and N,N'-ethylene bis stearamide.
  • fatty acid salts include fatty acid salts, fatty acid amides, silane polymers, solid paraffin, liquid paraffin, calcium stearate, zinc stearate, stearamide, silicone powder, methylene bis stearamide and N,N'-ethylene bis stearamide.
  • the content of other additives in the foamed material according to the present invention is within a range that does not impair the effects of the present invention. and the total content is preferably in the range of 0.1 to 22.5% by mass.
  • the foamed material according to the present invention is obtained by appropriately mixing the above-mentioned components. Specifically, a mixture obtained by dry blending a resin or the like, the chemical foaming agent composition of the present invention, an optionally contained flame retardant, and other additives that may be contained as necessary. is used as a foam material.
  • the chemical foaming agent masterbatch of the present invention may be used instead of the chemical foaming agent composition of the present invention. That is, a mixture obtained by dry blending a resin or the like, the chemical foaming agent masterbatch of the present invention, an optionally contained flame retardant, and other additives that may be contained as necessary is used as a foaming material. may be When a chemical foaming agent masterbatch is used to prepare a foaming material, the content of the resin, etc. in the foaming material is the sum of the amount of the resin, etc. in the chemical foaming agent masterbatch and the amount of the resin, etc. added separately. be.
  • a foaming material may be formed by melt-kneading the mixture obtained above.
  • the following operations may be performed to suppress the decomposition of sodium hydrogencarbonate and the reaction between sodium hydrogencarbonate and the acidic substance A as much as possible, that is, to suppress foaming.
  • the operations include applying pressure to the melt-kneaded material, setting the temperature of the melt-kneaded material to a low temperature, and cooling the melt-kneaded material immediately after melt-kneading.
  • the foaming material according to the present invention can take various forms such as powder, granules, tablets, pellets, flakes, fibers, and liquid, depending on the preparation method described above. can.
  • the foam of the present invention is obtained by foam-molding the above foam material.
  • the foam molding method is not particularly limited, and a known foam molding method using sodium hydrogen carbonate as a chemical foaming agent can be applied.
  • a foam is obtained by molding the above-mentioned foam material and heating it to the decomposition temperature of sodium hydrogen carbonate or higher.
  • a preferable foam-molding method for obtaining the foam of the present invention is the production method of the present invention, which will be described later.
  • the foam of the present invention is a foam in which the cell diameter of the foam is fine and the decrease in flame retardancy is suppressed.
  • the cell diameter of the foam of the present invention is preferably 0.4 mm or less, more preferably 0.2 mm or less, as an average cell diameter measured by the following method.
  • the foam is cut with a cutter or the like, and the cross section is observed with a transmission electron microscope such as JEM-2000FX (manufactured by JEOL Ltd.) to take an image of the foamed portion.
  • the foamed part means, for example, when the foam is molded in a mold, the foamed part has a dense skin layer in which the foam has almost no cells, and the foamed part has uniform cells. The region where uniform bubbles can be observed near the center of the cross section, excluding the skin layer vicinity where the
  • the maximum diameter of all existing bubbles was measured for a randomly selected measurement area of 2 mm ⁇ 8 mm using an image measuring machine (NEXIV VMR3020), and the average bubble diameter was averaged.
  • the flame retardancy of the foam of the present invention can be evaluated using, for example, the burning time measured in the following burning test as an index.
  • the burning time measured in the following burning test as an index.
  • a molded article obtained by molding a molding material that does not contain the chemical foaming agent composition of the present invention is subjected to the following combustion test with a combustion time T1, and the foam of the present invention is obtained. Assuming that the combustion time is T2 in the following combustion test, it is preferable that T2 does not greatly increase compared to T1.
  • T2/T1 is preferably 2.0 or less, more preferably 1.5 or less.
  • T2 is preferably 30 seconds or less, more preferably 10 seconds or less, in consideration of the ASTM D3801 standard.
  • the burning time is measured by a 20 mm vertical burning test according to ASTM D3801.
  • test pieces three test pieces having a size of 125 ⁇ 5 mm ⁇ 13 ⁇ 0.5 mm and a thickness of 2 mm are prepared. Each test piece is vertically attached to a clamp, and a burner is used at the lower end of the test piece to apply two 10-second indirect flames with a 20 mm flame, and the combustion behavior is judged.
  • the burning time was obtained by the following method. That is, for each test piece, the longer of the flaming combustion times in two flame contact times is adopted as the combustion time. The average of the burning times for the three test pieces was taken as the burning time.
  • the use of the foam of the present invention is not particularly limited, and examples include electric and electronic parts, electrical components, exterior parts, and interior parts in the fields of home appliances and automobiles, as well as various packaging materials, household goods, and office supplies. , piping, and agricultural materials.
  • the method for producing a foam of the present invention is characterized by having the following (1) foam material preparation step and (2) foam molding step.
  • a step of mixing the chemical blowing agent composition of the present invention or the chemical blowing agent masterbatch of the present invention with a thermoplastic resin or thermoplastic elastomer (resin or the like) to obtain a foaming material (foaming material preparation step)
  • a step of foam-molding the foamed material obtained in (1) above with an injection molding machine (foam molding step)
  • the production method of the present invention may have steps other than (1) foam material preparation step and (2) foam molding step, if necessary. Each step will be described below.
  • the foaming material preparation step in the production method of the present invention can be carried out in the same manner as the foaming material preparation method described in the above foam.
  • the content of each component in the foam material can also be set to the same amount as the content of each component in the foam material described above for the foam.
  • a mixture obtained by dry blending a resin or the like, the chemical foaming agent composition of the present invention, an optionally contained flame retardant, and other additives that may be contained as necessary. is used as a foam material.
  • the foaming material may be prepared using the chemical blowing agent masterbatch of the present invention instead of the chemical blowing agent composition of the present invention.
  • the content of the resin, etc. in the foaming material is the sum of the amount of the resin, etc. in the chemical foaming agent masterbatch and the amount of the resin, etc. added separately. be.
  • the foaming material may be prepared by melt-kneading.
  • the following operations may be performed to suppress the decomposition of sodium hydrogencarbonate and the reaction between sodium hydrogencarbonate and the acidic substance A as much as possible, that is, to suppress foaming.
  • the operations include applying pressure to the melt-kneaded material, setting the temperature of the melt-kneaded material to a low temperature, and cooling the melt-kneaded material immediately after melt-kneading.
  • melt-kneading is generally performed using a kneading device such as a Banbury mixer, roll, plastograph, extruder (single-screw extruder, multi-screw extruder (e.g., twin-screw extruder), etc.), and kneader.
  • a kneading device such as a Banbury mixer, roll, plastograph, extruder (single-screw extruder, multi-screw extruder (e.g., twin-screw extruder), etc.), and kneader.
  • melt-kneading is preferably carried out using an extruder because of its high production efficiency.
  • a multi-screw extruder is preferably used for melt-kneading, and a twin-screw extruder is more preferably used, since high shearability can be imparted.
  • the term extruder is used in a category
  • the temperature and pressure during melt-kneading should be such that the decomposition of sodium hydrogen carbonate and the reaction between sodium hydrogen carbonate and acidic substance A are suppressed as much as possible.
  • the kneading melt temperature corresponds to the cylinder temperature.
  • the screw rotation speed is preferably in the range of 50 to 300 rpm. Further, the discharge rate of the foamed material from the extruder is preferably in the range of 1 to 50 kg/hr.
  • the strand-shaped kneaded material can be processed into pellets, flakes, or the like.
  • the foam molding step in the production method of the present invention is a step of foam molding the foamed material obtained above using an injection molding machine.
  • the injection molding machine includes, for example, a cylinder that heats the foam material, an injection part that communicates with the cylinder and injects the heated foam material from the cylinder, and a mold for molding the injected foam material into a predetermined shape.
  • a general injection molding machine can be used.
  • the heating of the foaming material in the cylinder is the temperature at which the foaming material can be injected from the injection part (viscosity).
  • the heating temperature is, for example, a temperature equal to or higher than the melting temperature of resin or the like contained in the foam material.
  • the heating temperature of the foam material is preferably in the range of 190 to 220°C, more preferably 200 to 210°C.
  • the heating temperature of the foam material is preferably in the range of 220-240.degree. It should be noted that the temperature of the foaming material inside the cylinder can be treated as substantially the same as the temperature of the cylinder. Even if the temperature of the foaming material rises above the decomposition temperature of sodium bicarbonate in the cylinder filled with the foaming material, foaming does not occur because the foaming material cannot increase its volume under the sealed condition.
  • the injection conditions are adjusted as appropriate according to the structure of the injection molding machine, especially the structure of the injection section.
  • the injection pressure is the pressure at which the heated foaming material can be injected from the cylinder into the cavity of the mold, and can be in the range of approximately 10 to 200 MPa.
  • the injection time that is, the time from the start of injection to the end of injection, is preferably within 2 seconds, for example.
  • the injection speed is appropriately adjusted according to, for example, the type of resin used, the shape of the product, the thickness of the product, and the like.
  • the foam material injected into the mold cavity is foam-molded into the shape of the cavity.
  • the volume of the cavity of the mold used is set larger than the volume of the raw foaming material, and the foaming material injected by injection expands in the cavity of the mold, thereby filling the entire cavity with foam. .
  • a value obtained by dividing the volume of the mold cavity by the volume of the foaming material used corresponds to the expansion ratio.
  • the temperature of the foam material during foam molding is a temperature equal to or higher than the decomposition temperature of sodium hydrogencarbonate, preferably in the range of 170 to 230°C.
  • the temperature of the foam material during foam molding may be estimated, for example, as the temperature of the foam material during injection, that is, the temperature of the cylinder.
  • the mold may be a mold with a fixed cavity volume, or a mold with a variable cavity volume.
  • a mold with a variable cavity volume the volume is kept small when the foam material is filled, and by expanding the cavity volume after filling, the generation and expansion of air bubbles can be actively promoted.
  • Such a molding method is called core-back molding. According to core-back molding, a skin layer is formed when the foam material contacts the mold, so a foam with a good surface appearance can be obtained.
  • the conditions for core-back molding from the viewpoint of performing uniform foaming, it is preferable to shorten the time from the end of filling the cavity with the foaming material to the start of expanding the volume of the cavity, for example, within 2 seconds.
  • the temperature of the mold can be set to the cooling temperature from the time of injection of the foam material.
  • the cooling temperature (the temperature of the mold and foam) is preferably 40 to 80°C, for example.
  • the cooling time is appropriately adjusted according to, for example, the type of resin used, the shape of the product, the thickness of the product, and the like.
  • Chemical Blowing Agent Compositions 10 to 13 of the present invention and Chemical Blowing Agent Compositions 1 to 9 of Comparative Examples were prepared by mixing 1 part by mass of each of the compounds shown in Table I with 0.2 part by mass of sodium hydrogen carbonate.
  • Chemical Blowing Agent Compositions 14-15 were prepared.
  • Table I shows the melting point of the compound, the pH when the compound is made into an aqueous solution, and whether the compound is an organic compound or an inorganic compound.
  • Table I also shows the content of the organic compound having a melting point of less than 400°C in the chemical foaming agent composition as a content B [% by mass].
  • a foam with an expansion ratio of 1.1 under the following injection molding condition 1 (the size of the foam is for measuring the burning time (which is the same size as the test piece of ) was molded.
  • the cylinder temperature corresponds to the foam temperature in the cylinder and during injection.
  • a mold having a fixed volume was used. Also, no pressure was applied to the mold during foam molding.
  • the mold temperature corresponds to the cooling temperature.
  • injection molding condition 1 Cylinder temperature (foaming material temperature); 200°C Injection pressure; 20MPa Injection time (time from injection start to injection end); 0.9 seconds Injection speed; 40 [mm/s] Mold temperature; 50°C Cooling time; 15 seconds
  • the cell diameter and burning time (T2) were measured by the methods described above.
  • a resin composition that does not contain the chemical foaming agent composition 1 was prepared, and the molded body obtained by injection molding was measured for the combustion time (T1), which was 4.9 [sec. ]Met.
  • Table I shows T2/T1 and T2-T1 along with bubble diameter and burning time (T2).
  • FIG. 1 shows a graph showing the relationship between the pH of the compound used in combination with sodium hydrogen carbonate (measurement temperature 23° C.) and the cell diameter of the resulting foam.
  • Foaming materials 21 to 29 shown in Table II were prepared using the chemical foaming agent compositions 10 to 13 obtained above and the following thermoplastic resins and flame retardants.
  • Foam materials 33-35 were prepared using chemical blowing agent composition 3 consisting of (outside the range of acidic substance A).
  • thermoplastic resin Polypropylene; Novatec PP_MG03BD (product name, manufactured by Japan Polypropylene Corporation, hereinafter referred to as "PP”.
  • ABS resin Cebian V_660SF (product name, manufactured by Daicel Polymer Ltd., hereinafter referred to as "ABS”).
  • Polyamide resin Amilan_CM1017 (product name, manufactured by Toray Industries, Inc., hereinafter referred to as "PA”.
  • Flame retardant 1 Bis[3,5-dibromo-4-(2,3-dibromopropoxy)phenyl]sulfone (hereinafter referred to as “flame retardant 1”) Bis(pentabromophenyl)ethane (hereinafter referred to as “flame retardant 2”) Condensed phosphate ester (PX-200 (product name, manufactured by Daihachi Chemical Industry Co., Ltd., hereinafter referred to as “flame retardant 3”)
  • injection molding condition 2 Cylinder temperature (foaming material temperature); 220°C Injection pressure; 20MPa Injection time (time from injection start to injection end); 0.9 seconds Injection speed; 40 [mm/s] Mold temperature; 50°C Cooling time; 15 seconds
  • injection molding condition 3 Cylinder temperature (foaming material temperature); 250°C Injection pressure; 20MPa Injection time (time from injection start to injection end); 0.9 seconds Injection speed; 40 [mm/s] Mold temperature; 70°C Cooling time; 15 seconds
  • the cell diameter and burning time (T2) were measured by the methods described above. Also, for each foaming material, a chemical foaming agent composition or a resin composition containing no sodium hydrogencarbonate was prepared, and the combustion time (T1) was measured for the molding obtained by injection molding. Table III shows T2/T1 and T2-T1, along with bubble diameter, combustion time (T2), and combustion time (T1).
  • the foam of the present invention achieves the effect of the present invention, that is, both miniaturization of cells and suppression of deterioration in flame retardancy.
  • a chemical foaming agent composition and a chemical foaming agent masterbatch that can achieve both miniaturization of cells and suppression of deterioration in flame retardancy when used for molding a foam.
  • a foam produced using the chemical foaming agent composition or the chemical foaming agent masterbatch which achieves both miniaturization of cells and suppression of deterioration in flame retardancy, and a method for producing the same.

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Abstract

The present invention addresses the problem of providing a chemical foaming agent composition and a chemical foaming agent master batch, each of which is capable of achieving a good balance between miniaturization of air bubbles and suppression of decrease in flame retardancy if used for molding of a foam. The present invention provides: a foam which is produced using the above-described chemical foaming agent composition or chemical foaming agent master batch, and which has achieved both miniaturization of air bubbles and suppression of decrease in flame retardancy; and a method for producing this foam. A thermoplastic resin composition according to the present invention is a chemical foaming agent composition which contains sodium hydrogen carbonate and an acidic substance, wherein the acidic substance is an inorganic compound or an organic compound that has a melting point of 400°C or more.

Description

化学発泡剤組成物、化学発泡剤マスターバッチ、発泡体及び発泡体の製造方法Chemical blowing agent composition, chemical blowing agent masterbatch, foam and method for producing foam
　本発明は、化学発泡剤組成物、化学発泡剤マスターバッチ、発泡体及び発泡体の製造方法に関する。より詳しくは、本発明は、発泡体の成形に用いた際に気泡の微細化と難燃性低下の抑制が両立できる化学発泡剤組成物及び化学発泡剤マスターバッチ、さらに、当該化学発泡剤組成物又は化学発泡剤マスターバッチを用いて製造された気泡の微細化と難燃性低下の抑制が共に達成された発泡体及びその製造方法に関する。 The present invention relates to a chemical foaming agent composition, a chemical foaming agent masterbatch, a foam, and a method for producing a foam. More specifically, the present invention provides a chemical foaming agent composition and a chemical foaming agent masterbatch that are capable of both miniaturizing cells and suppressing deterioration of flame retardancy when used for molding a foam, and furthermore, the chemical foaming agent composition. The present invention relates to a foam produced by using a physical or chemical foaming agent masterbatch, in which both cell miniaturization and reduction in flame retardancy are suppressed, and a method for producing the same.
　自動車や電化製品等に使用される外装部品や構造部品に用いる樹脂又はエラストマーの発泡体の成形には、ヒケ（成形収縮により生じる凹み等）やソリの抑制のために射出発泡成形が採用されることが増えている。中でも小ロット生産をする部品は設備投資が安価な化学発泡方式を選択すれば製品単価が安くなりコスト面で有利である。 Injection foam molding is used to suppress sink marks (dents caused by molding shrinkage) and warpage in the molding of resin or elastomer foams used for exterior parts and structural parts used in automobiles and electrical appliances. things are increasing. In particular, for parts that are produced in small lots, if the chemical foaming method, which requires less equipment investment, is selected, the unit price of the product will be reduced, which is advantageous in terms of cost.
　化学発泡方式では、熱分解又は化学反応により気体を発生する化学発泡剤が使用される。化学発泡方式で得られる発泡体は、一昔前は内部の気泡径が大きいことが原因で外観品質悪化及び強度低下が問題になっていた。しかしながら、近年では、樹脂又はエラストマーに、化学発泡剤と共に発泡助剤を加えることで気泡を微細化する技術が開発されており、外装部品や構造部品としても問題ない品質が確保できるようになっている。 The chemical foaming method uses a chemical foaming agent that generates gas through thermal decomposition or chemical reaction. A decade ago, foams obtained by the chemical foaming method had problems of deterioration in appearance quality and reduction in strength due to large internal cell diameters. However, in recent years, a technology has been developed to refine the air bubbles by adding a chemical foaming agent and a foaming aid to resins or elastomers. there is
　なお、「化学発泡剤」とは、樹脂等に混合し発泡体を得るための薬品のうち、熱分解又は化学反応によりガス（気泡）を発生する化合物を指す。「化学発泡剤組成物」とは、化学発泡剤と、化学発泡剤以外の成分である助剤とからなる組成物をいう。「化学発泡剤マスターバッチ」は、熱可塑性樹脂又は熱可塑性エラストマーに化学発泡剤又は化学発泡剤組成物を混ぜ合わせた組成物である。 "Chemical foaming agent" refers to a compound that generates gas (bubbles) by thermal decomposition or chemical reaction, among the chemicals used to obtain a foam by mixing with resin or the like. "Chemical foaming agent composition" refers to a composition comprising a chemical foaming agent and an auxiliary agent other than the chemical foaming agent. A "chemical blowing agent masterbatch" is a composition that combines a thermoplastic resin or thermoplastic elastomer with a chemical blowing agent or chemical blowing agent composition.
　例えば、特許文献１には、熱可塑性樹脂に、熱分解型発泡剤にクエン酸塩とリチウム化合物（ただし、リチウム塩は除く）又は亜鉛華を含んだ発泡剤組成物を添加することで、微細な気泡で発泡成形される発泡剤組成物および熱可塑性樹脂発泡体の製造方法が記載されている。 For example, in Patent Document 1, a foaming agent composition containing a citrate and a lithium compound (but excluding lithium salt) or zinc oxide is added to a thermally decomposable foaming agent to a thermoplastic resin to obtain fine particles. A blowing agent composition that is foam molded with fine cells and a method for producing a thermoplastic resin foam are described.
　また、特許文献２には、樹脂の発泡体を成形するのに用いられる発泡剤組成物であって、熱分解型発泡剤である炭酸水素ナトリウムと、ステアリン酸リチウムと、クエン酸モノナトリウムと、亜鉛、タルク及びシリカの少なくとも１つを、それぞれ所定の量含有する発泡剤組成物が記載されている。特許文献２には、この発泡剤組成物を用いて、樹脂を発泡成形することで、気泡を微細で均一な分布なものとすることができ、平面平滑性等の外観や基材性能などに優れた発泡体が得られることが記載されている。 Further, Patent Document 2 discloses a foaming agent composition used for molding a resin foam, comprising sodium bicarbonate, which is a thermally decomposable foaming agent, lithium stearate, monosodium citrate, Blowing agent compositions are described that contain predetermined amounts of at least one of zinc, talc, and silica. In Patent Document 2, by foam molding a resin using this foaming agent composition, fine and uniform distribution of cells can be achieved, and appearance such as planar smoothness and substrate performance are improved. Excellent foams are said to be obtained.
　ここで、上記自動車や電化製品等の部品には発泡体としての特性とともに、難燃性が求められている。そのため、発泡体を成形する際にも、樹脂の種類に応じて、適宜、難燃剤が添加される。しかしながら、特許文献１及び特許文献２に記載の熱分解型発泡剤と上記所定の成分を組み合わせた発泡剤組成物を用いて得られる発泡体は、樹脂及び難燃剤の種類に関係なく難燃性が低下することが問題であった。 Here, in addition to foam characteristics, flame retardancy is required for parts such as automobiles and electrical appliances. Therefore, when molding a foam, a flame retardant is added as appropriate according to the type of resin. However, the foams obtained by using the foaming agent compositions obtained by combining the thermally decomposable foaming agents described in Patent Documents 1 and 2 with the above-described predetermined components are flame retardant regardless of the types of resin and flame retardant. was a problem.
特許第４１９６２３８号公報Japanese Patent No. 4196238 特許第４１１００３２号公報Japanese Patent No. 4110032
　本発明は、上記問題・状況に鑑みてなされたものであり、その解決課題は、発泡体の成形に用いた際に気泡の微細化と難燃性低下の抑制が両立できる化学発泡剤組成物及び化学発泡剤マスターバッチを提供することである。また、上記化学発泡剤組成物又は化学発泡剤マスターバッチを用いて製造された気泡の微細化と難燃性低下の抑制が共に達成された発泡体及びその製造方法を提供することである。 The present invention has been made in view of the above-mentioned problems and circumstances, and the problem to be solved is a chemical foaming agent composition that can achieve both miniaturization of cells and suppression of deterioration in flame retardancy when used for molding foams. and to provide a chemical blowing agent masterbatch. Another object of the present invention is to provide a foam produced using the above-mentioned chemical foaming agent composition or chemical foaming agent masterbatch, which achieves both miniaturization of cells and suppression of deterioration in flame retardancy, and a method for producing the same.
　本発明者は、上記課題を解決すべく、上記問題の原因等について検討する過程において、化学発泡剤として炭酸水素ナトリウムを選択し、これと組み合わせる発泡助剤として、特定の酸性物質を選択して化学発泡剤組成物とすることで、当該化学発泡剤組成物を用いて得られる発泡体は、気泡の微細化と難燃性低下の抑制が共に達成された発泡体であることを見出し本発明に至った。すなわち、本発明に係る上記課題は、以下の手段により解決される。 In order to solve the above problems, the present inventors selected sodium bicarbonate as a chemical foaming agent and selected a specific acidic substance as a foaming aid combined with it in the process of studying the causes of the above problems. It has been found that by using a chemical blowing agent composition, the foam obtained using the chemical blowing agent composition is a foam that achieves both miniaturization of cells and suppression of deterioration in flame retardancy. reached. That is, the above problems related to the present invention are solved by the following means.
　１．炭酸水素ナトリウムと酸性物質とを含有する化学発泡剤組成物であって、前記酸性物質が、無機化合物又は融点が４００℃以上の有機化合物である化学発泡剤組成物。 1. A chemical blowing agent composition containing sodium bicarbonate and an acidic substance, wherein the acidic substance is an inorganic compound or an organic compound having a melting point of 400° C. or higher.
　２．前記化学発泡剤組成物の全量に対して、融点が４００℃未満の有機化合物を５８質量％以下の範囲内で含有する第１項に記載の化学発泡剤組成物。 2. 2. The chemical blowing agent composition according to claim 1, containing 58% by mass or less of an organic compound having a melting point of less than 400° C. based on the total amount of the chemical blowing agent composition.
　３．前記酸性物質が、ホウ酸、三酸化二ホウ素、リン酸二水素ナトリウム及び亜硫酸水素ナトリウムから選ばれる少なくとも１種を含む第１項又は第２項に記載の化学発泡剤組成物。 3. 3. The chemical blowing agent composition according to item 1 or 2, wherein the acidic substance comprises at least one selected from boric acid, diboron trioxide, sodium dihydrogen phosphate and sodium hydrogen sulfite.
　４．第１項から第３項までのいずれか一項に記載の化学発泡剤組成物と、熱可塑性樹脂又は熱可塑性エラストマーと、を含有する化学発泡剤マスターバッチ。 4. A chemical blowing agent masterbatch containing the chemical blowing agent composition according to any one of items 1 to 3 and a thermoplastic resin or thermoplastic elastomer.
　５．第１項から第３項までのいずれか一項に記載の化学発泡剤組成物又は第４項に記載の化学発泡剤マスターバッチと、熱可塑性樹脂又は熱可塑性エラストマーと、を含有する発泡材料を発泡成形した発泡体。 5. A foaming material containing the chemical blowing agent composition according to any one of items 1 to 3 or the chemical blowing agent masterbatch according to item 4, and a thermoplastic resin or thermoplastic elastomer A foam molded by foaming.
　６．前記発泡体の全量に対する、前記化学発泡剤組成物由来の融点が４００℃未満の有機化合物の含有割合が、１質量％以下の範囲内である第５項に記載の発泡体。 6. 6. The foam according to claim 5, wherein the content of the chemical foaming agent composition-derived organic compound having a melting point of less than 400° C. is within the range of 1% by mass or less relative to the total amount of the foam.
　７．前記熱可塑性樹脂又は熱可塑性エラストマーが、ポリオレフィン樹脂、アクリロニトリル－ブタジエン－スチレン樹脂、ポリスチレン樹脂、ポリアミド樹脂、ポリ塩化ビニル樹脂、エチレン酢酸ビニル樹脂及び熱可塑性エラストマーから選ばれる少なくとも１種を含む第５項又は第６項に記載の発泡体。 7. Item 5, wherein the thermoplastic resin or thermoplastic elastomer contains at least one selected from polyolefin resins, acrylonitrile-butadiene-styrene resins, polystyrene resins, polyamide resins, polyvinyl chloride resins, ethylene vinyl acetate resins and thermoplastic elastomers. Or the foam according to item 6.
　８．さらに、難燃剤を含有する第５項から第７項までのいずれか一項に記載の発泡体。 8. 8. The foam of any one of paragraphs 5-7, further comprising a flame retardant.
　９．第１項から第３項までのいずれか一項に記載の化学発泡剤組成物又は第４項に記載の化学発泡剤マスターバッチと、熱可塑性樹脂又は熱可塑性エラストマーとを混合して発泡材料を得る工程と、前記発泡材料を射出成形機にて発泡成形する工程と、を有する発泡体の製造方法。 9. A foaming material is produced by mixing the chemical blowing agent composition according to any one of items 1 to 3 or the chemical blowing agent masterbatch according to item 4 with a thermoplastic resin or a thermoplastic elastomer. and foam-molding the foam material with an injection molding machine.
　１０．前記発泡材料における前記熱可塑性樹脂又は熱可塑性エラストマーの総量に対する前記化学発泡剤組成物の割合が０．１～１．７質量％の範囲内にある第９項に記載の発泡体の製造方法。 10. 10. The method for producing a foam according to item 9, wherein the ratio of the chemical blowing agent composition to the total amount of the thermoplastic resin or thermoplastic elastomer in the foam material is within the range of 0.1 to 1.7% by mass.
　本発明の上記手段により、発泡体の成形に用いた際に気泡の微細化と難燃性低下の抑制が両立できる化学発泡剤組成物及び化学発泡剤マスターバッチを提供することができる。また、上記化学発泡剤組成物又は化学発泡剤マスターバッチを用いて製造された気泡の微細化と難燃性低下の抑制が共に達成された発泡体及びその製造方法を提供することができる。 By the above-described means of the present invention, it is possible to provide a chemical foaming agent composition and a chemical foaming agent masterbatch that can achieve both miniaturization of cells and suppression of deterioration in flame retardancy when used for molding foams. In addition, it is possible to provide a foam produced using the chemical foaming agent composition or the chemical foaming agent masterbatch, which achieves both miniaturization of cells and suppression of deterioration in flame retardancy, and a method for producing the same.
　本発明の効果の発現機構ないし作用機構については、明確にはなっていないが、以下のように推察している。 Although the expression mechanism or action mechanism of the effects of the present invention has not been clarified, it is speculated as follows.
　炭酸水素ナトリウムは、加熱又は酸により以下の式（１）又は式（２）に示すように分解してＣＯ２を発生する。
式（１）：　　２ＮａＨＣＯ３→Ｎａ２ＣＯ３＋Ｈ２Ｏ＋ＣＯ２
式（２）：　　ＮａＨＣＯ３＋ＨＡ→ＮaＡ＋Ｈ２Ｏ＋ＣＯ２
（式（２）中、ＨＡは、プロトンＨ＋を放出する酸を表す。Ａは、酸ＨＡの共役塩基を表す。） Sodium bicarbonate is decomposed by heating or acid to generate CO 2 as shown in the following formula (1) or (2).
Formula (1): 2NaHCO3 → Na2CO3 + H2O + CO2
Formula (2): NaHCO3 +HA→NaA+ H2O + CO2
(In formula (2), HA represents an acid that releases protons H + . A represents the conjugate base of acid HA.)
　炭酸水素ナトリウムを樹脂やエラストマーに混錬して成形し加熱すると、炭酸水素ナトリウムの熱又は酸による分解反応により発生したＣＯ２が、樹脂やエラストマー等のマトリックス内で気泡を形成して発泡体が得られる。 When sodium bicarbonate is kneaded with resin or elastomer, molded and heated, CO2 generated by the decomposition reaction of sodium bicarbonate due to heat or acid forms bubbles in the matrix of resin or elastomer, resulting in a foam. can get.
　従来、炭酸水素ナトリウムにクエン酸塩等の有機酸化合物を発泡助剤として組み合わせることで、発泡体中の気泡が微細化されることが知られている。また、タルク、シリカ、炭酸カルシウム等の無機物を発泡助剤として用いることで、発泡体中の気泡が微細化されるとされている。通常、樹脂内部で炭酸水素ナトリウムが分解して発泡する場合、発泡体中の気泡が大きくなるのは、気泡が結合したり、気泡が破裂して気泡同士が連通したりすることによるものと考えられている。系内に発泡助剤が存在することで、当該発泡助剤が気泡核となって気泡数を増加させることができ、結果として気泡の結合や破裂を抑制して、発泡の微細化に寄与すると考えられている。 Conventionally, it is known that by combining sodium bicarbonate with an organic acid compound such as citrate as a foaming aid, the bubbles in the foam can be made finer. In addition, it is reported that the use of an inorganic substance such as talc, silica, calcium carbonate, etc. as a foaming aid makes the bubbles in the foam finer. Normally, when sodium bicarbonate decomposes and foams inside a resin, the reason why the bubbles in the foam grow is thought to be that the bubbles combine or rupture and communicate with each other. It is The presence of a foaming aid in the system allows the foaming aid to act as cell nuclei and increase the number of cells. It is considered.
　本発明者らは、得られる発泡体の難燃性の低下を抑制できる観点から、無機化合物について検討したところ、無機化合物のうちでも特に酸性物質が、発泡体の難燃性の低下を抑制しながら、炭酸水素ナトリウムによる気泡を微細化する能力にも優れることを見出した。さらに、有機化合物であっても、融点が４００℃以上の酸性物質であれば、無機酸性物質と同様の効果が得られることを見出したものである。 The inventors of the present invention have investigated inorganic compounds from the viewpoint of suppressing the deterioration of the flame retardancy of the obtained foam, and found that, among inorganic compounds, acidic substances in particular suppress the deterioration of the flame retardancy of the foam. However, it was found that sodium bicarbonate is also excellent in the ability to make air bubbles fine. Furthermore, the inventors have found that even if an organic compound is used, an acidic substance having a melting point of 400° C. or higher can provide the same effect as an inorganic acidic substance.
　炭酸水素ナトリウムは単独で用いた場合には、式（１）で示されるとおり熱分解により気泡（ＣＯ２ガス）を発生する。本発明の化学発泡剤組成物においては、炭酸水素ナトリウムは上記酸性物質と式（２）に示される化学反応を生起し、気泡（ＣＯ２ガス）を発生する。ここで、炭酸水素ナトリウムの分解温度は２７０℃とされているが、式（１）の分解反応は、概ね５０℃から徐々に起こることが知られている。しかしながら、式（２）の化学反応は、式（１）の反応より、低温で生起すると考えられる。 When sodium hydrogen carbonate is used alone, it generates bubbles (CO 2 gas) by thermal decomposition as shown in formula (1). In the chemical foaming agent composition of the present invention, sodium bicarbonate causes the chemical reaction represented by the above acidic substance and formula (2) to generate bubbles (CO 2 gas). Here, the decomposition temperature of sodium hydrogen carbonate is 270°C, but it is known that the decomposition reaction of formula (1) occurs gradually from about 50°C. However, the chemical reaction of formula (2) is believed to occur at a lower temperature than the reaction of formula (1).
　このように、炭酸水素ナトリウムは、式（２）のように酸性物質と反応する方が低温で気泡（ＣＯ２ガス）を発生する。そして、このような低温で発泡が起こった場合、樹脂やエラストマー等のマトリックスは粘度が高い状態にあるため、発泡したガスからなる気泡が合体しにくく、結果として発泡の微細化に寄与すると考えている。 Thus, sodium bicarbonate generates bubbles ( CO2 gas) at a lower temperature when it reacts with an acidic substance as in equation (2). When foaming occurs at such a low temperature, the viscosity of the matrix such as resin or elastomer is in a state of high viscosity, so it is difficult for the foamed gas bubbles to coalesce. there is
　さらに、式（１）による炭酸水素ナトリウム単体の熱分解では、炭酸水素ナトリウム２分子から、１分子のＣＯ２が生成するのに比べ、式（２）による炭酸水素ナトリウムと酸性物質の反応では、炭酸水素ナトリウム１分子に対して１分子のＣＯ２が生成する。すなわち、生成ガス量が増加することで、発泡の微細化に寄与するとも考えている。 Furthermore, in the thermal decomposition of sodium hydrogen carbonate alone according to formula (1), one molecule of CO 2 is generated from two molecules of sodium hydrogen carbonate, whereas the reaction between sodium hydrogen carbonate and an acidic substance according to formula (2) produces: One molecule of CO 2 is produced for one molecule of sodium bicarbonate. In other words, it is believed that an increase in the amount of generated gas contributes to finer foaming.
　また、難燃性の低下を抑制できる点については、酸性物質のうちでも有機化合物は、燃焼時に可燃性ガスを発生させるため燃えやすくなると推察した。ただし、酸性物質として、融点が高い（４００℃以上）有機化合物（酸性物質）を用いれば、難燃性が殆ど低下しないことを本発明者らは見出した。融点が高い（４００℃以上）有機化合物で難燃性が低下しない理由は、このような有機化合物では、可燃性ガスを発生させるタイミングが遅く、消火までに可燃性ガスが発生しないためと推察している。 In addition, regarding the ability to suppress the deterioration of flame retardancy, it was speculated that among acidic substances, organic compounds are more likely to burn because they generate combustible gas when burned. However, the present inventors have found that if an organic compound (acidic substance) with a high melting point (400° C. or higher) is used as the acidic substance, the flame retardancy is hardly lowered. The reason why the flame retardancy of organic compounds with a high melting point (400°C or higher) does not decrease is presumed that the timing of generating combustible gas is delayed in such organic compounds, and combustible gas is not generated until the fire is extinguished. ing.
炭酸水素ナトリウムと併用する化合物のｐＨと得られる発泡体の気泡径との関係を示すグラフGraph showing the relationship between the pH of the compound used in combination with sodium bicarbonate and the cell diameter of the resulting foam
　本発明の化学発泡剤組成物は、炭酸水素ナトリウムと酸性物質とを含有する化学発泡剤組成物であって、前記酸性物質が、無機化合物又は融点が４００℃以上の有機化合物であることを特徴とする。この特徴は、以下の化学発泡剤組成物の各実施形態に共通する技術的特徴である。 The chemical blowing agent composition of the present invention is a chemical blowing agent composition containing sodium hydrogencarbonate and an acidic substance, wherein the acidic substance is an inorganic compound or an organic compound having a melting point of 400° C. or higher. and This feature is a technical feature common to each embodiment of the chemical blowing agent composition below.
　本発明の化学発泡剤組成物の実施態様としては、前記化学発泡剤組成物は融点が４００℃未満の有機化合物を含有してもよく、その場合、難燃性低下の抑制の観点から、化学発泡剤組成物の全量に対する、融点が４００℃未満の有機化合物の含有割合を５８質量％以下の範囲内とすることが好ましい。 As an embodiment of the chemical blowing agent composition of the present invention, the chemical blowing agent composition may contain an organic compound having a melting point of less than 400°C. It is preferable that the content of the organic compound having a melting point of less than 400° C. is within a range of 58% by mass or less with respect to the total amount of the foaming agent composition.
　本発明の化学発泡剤組成物の実施態様としては、本発明の効果発現の観点から、前記酸性物質が、ホウ酸、三酸化二ホウ素、リン酸二水素ナトリウム及び亜硫酸水素ナトリウムから選ばれる少なくとも１種を含むことが好ましい。 As an embodiment of the chemical foaming agent composition of the present invention, from the viewpoint of exhibiting the effect of the present invention, the acidic substance is at least one selected from boric acid, diboron trioxide, sodium dihydrogen phosphate and sodium hydrogen sulfite. It preferably contains seeds.
　本発明の化学発泡剤マスターバッチは、本発明の化学発泡剤組成物と、熱可塑性樹脂又は熱可塑性エラストマーとを含有する。 The chemical blowing agent masterbatch of the present invention contains the chemical blowing agent composition of the present invention and a thermoplastic resin or thermoplastic elastomer.
　本発明の発泡体は、本発明の化学発泡剤組成物又は本発明の化学発泡剤マスターバッチと、熱可塑性樹脂又は熱可塑性エラストマーとを含有する発泡材料を発泡成形したことを特徴とする発泡体である。 The foam of the present invention is obtained by foam-molding a foam material containing the chemical foaming agent composition of the present invention or the chemical foaming agent masterbatch of the present invention and a thermoplastic resin or thermoplastic elastomer. is.
　本発明の発泡体の実施態様としては、難燃性の観点から、前記発泡体の全量に対する、前記化学発泡剤組成物由来の融点が４００℃未満の有機化合物の含有割合が、１質量％以下の範囲内であることが好ましい。 As an embodiment of the foam of the present invention, from the viewpoint of flame retardancy, the content of the organic compound derived from the chemical foaming agent composition and having a melting point of less than 400° C. relative to the total amount of the foam is 1% by mass or less. is preferably within the range of
　本発明の発泡体の実施態様としては、本発明の効果発現の観点から、前記熱可塑性樹脂又は熱可塑性エラストマーが、ポリオレフィン樹脂、アクリロニトリル－ブタジエン－スチレン樹脂、ポリスチレン樹脂、ポリアミド樹脂、ポリ塩化ビニル樹脂、エチレン酢酸ビニル樹脂及び熱可塑性エラストマーから選ばれる少なくとも１種を含むことが好ましい。 As an embodiment of the foam of the present invention, from the viewpoint of exhibiting the effects of the present invention, the thermoplastic resin or thermoplastic elastomer is polyolefin resin, acrylonitrile-butadiene-styrene resin, polystyrene resin, polyamide resin, polyvinyl chloride resin. , ethylene vinyl acetate resin and thermoplastic elastomer.
　本発明の発泡体の実施態様としては、本発明の効果発現の観点から、発泡体は、さらに、難燃剤を含有してもよい。 As an embodiment of the foam of the present invention, the foam may further contain a flame retardant from the viewpoint of exhibiting the effects of the present invention.
　本発明の発泡体の製造方法は、本発明の化学発泡剤組成物又は本発明の化学発泡剤マスターバッチと、熱可塑性樹脂又は熱可塑性エラストマーとを混合して発泡材料を得る工程と、前記発泡材料を射出成形機にて発泡成形する工程と、を有することを特徴とする。 The method for producing the foam of the present invention comprises the step of mixing the chemical foaming agent composition of the present invention or the chemical foaming agent masterbatch of the present invention with a thermoplastic resin or thermoplastic elastomer to obtain a foam material; and a step of foam-molding the material with an injection molding machine.
　本発明の発泡体の製造方法の実施態様としては、難燃性の観点から、前記発泡材料における前記熱可塑性樹脂又は熱可塑性エラストマーの総量に対する前記化学発泡剤組成物の割合が０．１～１．７質量％の範囲内にあることが好ましい。 As an embodiment of the foam production method of the present invention, from the viewpoint of flame retardancy, the ratio of the chemical foaming agent composition to the total amount of the thermoplastic resin or thermoplastic elastomer in the foam material is 0.1 to 1. It is preferably in the range of 0.7% by weight.
　以下、本発明とその構成要素、及び本発明を実施するための形態・態様について詳細な説明をする。なお、本願において、「～」は、その前後に記載される数値を下限値及び上限値として含む意味で使用する。本明細書において、「主成分とする」、「主として含有する」、「主体として構成される」は、全体に対して、主となる当該成分が全体の５０質量％以上、好ましくは６０質量％以上、より好ましくは７０質量％以上、さらに好ましくは８０質量％以上を占めることを意味する。 The following is a detailed description of the present invention, its components, and the forms and modes for carrying out the present invention. In the present application, "-" is used to mean that the numerical values before and after it are included as the lower limit and the upper limit. In the present specification, "mainly composed", "mainly contained", and "mainly composed" mean that the main component is 50% by mass or more, preferably 60% by mass, of the whole. 70% by mass or more, more preferably 80% by mass or more.
[化学発泡剤組成物]
　本発明の化学発泡剤組成物は、炭酸水素ナトリウムと酸性物質とを含有する化学発泡剤組成物であって、前記酸性物質が、無機化合物又は融点が４００℃以上の有機化合物であることを特徴とする。上記のとおり、化学発泡剤組成物は、化学発泡剤と、化学発泡剤以外の成分である助剤とからなる組成物である。助剤には、発泡助剤、ドリップ防止剤、酸化防止剤、滑剤、分散剤、核剤等が挙げられる。本発明の化学発泡剤組成物は、化学発泡剤として炭酸水素ナトリウムを含有し、助剤（発泡助剤）として、上記酸性物質を含有するものである。 [Chemical blowing agent composition]
The chemical blowing agent composition of the present invention is a chemical blowing agent composition containing sodium hydrogencarbonate and an acidic substance, wherein the acidic substance is an inorganic compound or an organic compound having a melting point of 400° C. or higher. and As described above, the chemical foaming agent composition is a composition comprising a chemical foaming agent and an auxiliary agent that is a component other than the chemical foaming agent. Auxiliaries include foaming aids, anti-drip agents, antioxidants, lubricants, dispersants, nucleating agents, and the like. The chemical foaming agent composition of the present invention contains sodium hydrogen carbonate as a chemical foaming agent and the acidic substance as an auxiliary agent (foaming auxiliary agent).
　本発明の化学発泡剤組成物において、炭酸水素ナトリウムは化学発泡剤として用いられる。炭酸水素ナトリウムは、上記式（１）又は式（２）のように分解してＣＯ２ガスを発生し、例えば、熱可塑性樹脂又は熱可塑性エラストマー（以下、「樹脂等」ということもある。）のマトリックス内に気泡を形成する。本発明の化学発泡剤組成物は、発泡体を成形するために用いられる。当該発泡体は、樹脂等を主成分とするマトリックスと気泡からなる。 Sodium bicarbonate is used as a chemical blowing agent in the chemical blowing agent composition of the present invention. Sodium bicarbonate decomposes as in the above formula (1) or formula (2) to generate CO 2 gas, for example, thermoplastic resin or thermoplastic elastomer (hereinafter sometimes referred to as "resin etc."). form air bubbles within the matrix of The chemical blowing agent composition of the present invention is used to form foams. The foam is composed of a matrix containing a resin or the like as a main component and cells.
　本発明の化学発泡剤組成物が含有する酸性物質（以下、「酸性物質Ａ」）は、無機化合物又は融点が４００℃以上である有機化合物である。なお、本発明に係る酸性物質には、水や水系媒体の共存下でプロトンＨ＋を解離し得る酸を生成する物質（例えば三酸化二ホウ素）も含む。本発明の化学発泡剤組成物において、酸性物質Ａは、化学発泡剤である炭酸水素ナトリウムの発泡を助ける発泡助剤として機能する。 The acidic substance contained in the chemical foaming agent composition of the present invention (hereinafter referred to as "acidic substance A") is an inorganic compound or an organic compound having a melting point of 400°C or higher. The acidic substance according to the present invention also includes a substance (for example, diboron trioxide) that generates an acid capable of dissociating protons H 3 + in the coexistence of water or an aqueous medium. In the chemical foaming agent composition of the present invention, the acidic substance A functions as a foaming aid that aids foaming of the chemical foaming agent, sodium hydrogen carbonate.
　以下、無機化合物である酸性物質を「酸性物質Ａ１」ともいい、融点が４００℃以上の有機化合物である酸性物質を「酸性物質Ａ２」ともいう。酸性物質Ａは、炭酸水素ナトリウムから発生したＣＯ２ガスを樹脂等のマトリックス内で微細な径の気泡として存在させるように機能する。これに加えて、酸性物質Ａは、発泡体のマトリックスを構成する樹脂等の難燃性の低下を招くことがなく、好ましくは難燃性を向上する性質を有する。なお、発泡体における気泡径及び難燃性の評価方法については後述のとおりである。 Hereinafter, an acidic substance that is an inorganic compound is also referred to as “acidic substance A1”, and an acidic substance that is an organic compound having a melting point of 400° C. or higher is also referred to as “acidic substance A2”. The acidic substance A functions to cause the CO 2 gas generated from sodium hydrogen carbonate to exist as fine bubbles in a matrix such as a resin. In addition to this, the acidic substance A preferably has a property of improving the flame retardancy without causing deterioration of the flame retardancy of the resin constituting the matrix of the foam. The method for evaluating the cell diameter and flame retardancy of the foam will be described later.
　本発明の化学発泡剤組成物は、本発明の効果を損なわない範囲で、炭酸水素ナトリウム及び酸性物質Ａ以外の任意成分を含有してもよい。任意成分としては、例えば、炭酸水素ナトリウム以外の化学発泡剤及び酸性物質Ａ以外の発泡助剤、ドリップ防止剤、酸化防止剤、滑剤、分散剤、核剤等が挙げられる。 The chemical foaming agent composition of the present invention may contain optional components other than sodium hydrogen carbonate and acidic substance A within a range that does not impair the effects of the present invention. Examples of optional components include chemical foaming agents other than sodium hydrogencarbonate, foaming aids other than acidic substance A, anti-drip agents, antioxidants, lubricants, dispersants, and nucleating agents.
　ただし、本発明の化学発泡剤組成物が任意成分を含有する場合、融点が４００℃未満の有機化合物の含有量は、化学発泡剤組成物の全量に対して、５８質量％以下とすることが好ましく、より好ましくは２２質量％以下である。本発明の化学発泡剤組成物は、融点が４００℃未満の有機化合物を含有しないことが特に好ましい。 However, when the chemical blowing agent composition of the present invention contains optional components, the content of the organic compound having a melting point of less than 400° C. may be 58% by mass or less with respect to the total amount of the chemical blowing agent composition. It is preferably 22% by mass or less, more preferably 22% by mass or less. It is particularly preferred that the chemical blowing agent composition of the present invention does not contain organic compounds with a melting point of less than 400°C.
〔化学発泡剤組成物の組成〕
　本発明の化学発泡剤組成物は、炭酸水素ナトリウムと酸性物質Ａを含有する。さらに、上記範囲で任意成分を含有してもよい。以下、本発明の化学発泡剤組成物が含有する各成分について説明する。 [Composition of chemical foaming agent composition]
The chemical blowing agent composition of the present invention contains sodium bicarbonate and acidic substance A. Furthermore, optional components may be contained within the above ranges. Each component contained in the chemical foaming agent composition of the present invention will be described below.
（炭酸水素ナトリウム）
　炭酸水素ナトリウムは、常温（２５℃）で固体（典型的には粉末状）の化学発泡剤であり、式（１）に示すとおり炭酸水素ナトリウム単体で熱分解をする。式（１）による炭酸水素ナトリウムの分解は５０℃から徐々に始まるとされる。 (sodium hydrogen carbonate)
Sodium hydrogen carbonate is a chemical foaming agent that is solid (typically powdery) at room temperature (25° C.), and thermally decomposes as a single unit of sodium hydrogen carbonate as shown in formula (1). Decomposition of sodium bicarbonate according to formula (1) is said to begin gradually at 50°C.
　本発明の化学発泡剤組成物においては、炭酸水素ナトリウムは、式（２）により酸性物質Ａと反応する。その場合、特に反応温度は確定していないことから、発泡体のマトリックスを主として構成する熱可塑性樹脂又は熱可塑性エラストマーに添加して成形を行うだけで気泡を発生させることができる。 In the chemical foaming agent composition of the present invention, sodium hydrogen carbonate reacts with acidic substance A according to formula (2). In that case, since the reaction temperature is not particularly fixed, cells can be generated simply by adding to the thermoplastic resin or thermoplastic elastomer that mainly constitutes the matrix of the foam and performing molding.
（酸性物質Ａ）
　酸性物質Ａは、典型的には常温（２５℃）で固体であって、粉体であることが好ましい。酸性物質Ａは、水や水系媒体の共存下でプロトンＨ＋を解離し得る、すなわち、酸性物質Ａを水溶液とした際のｐＨ（測定温度２３℃、以下、特に断りのない限り「ｐＨ」は当該物質の水溶液を温度２３℃で測定したｐＨである。）が７．０未満の物質であればよい。発泡体とした際の気泡微細化の観点から、酸性物質ＡのｐＨは４．６以下が好ましく、２．１～４．６の範囲がより好ましい。酸性物質Ａにおける粒子形状及び平均粒径は、例えば、共に用いる炭酸水素ナトリウムの粒子形状及び平均粒径と同様であることが好ましい。 (Acidic substance A)
The acidic substance A is typically solid at room temperature (25° C.) and preferably powder. The acidic substance A can dissociate protons H + in the presence of water or an aqueous medium. It is a pH of an aqueous solution of the substance measured at a temperature of 23° C.) is less than 7.0. The pH of the acidic substance A is preferably 4.6 or less, more preferably in the range of 2.1 to 4.6, from the viewpoint of miniaturization of cells when formed into a foam. The particle shape and average particle size of the acidic substance A are preferably the same as those of sodium hydrogen carbonate used together, for example.
　酸性物質Ａ１としては、例えば、ホウ酸、その無水物、ホウ酸塩、リン酸塩、亜硫酸塩、金属の酸性酸化物等の固体の酸又は酸の塩が挙げられる。酸性物質Ａとしては、これらの中でも、ホウ酸、三酸化二ホウ素、リン酸二水素ナトリウム及び亜硫酸水素ナトリウムから選ばれる１種以上が好ましい。 Examples of the acidic substance A1 include solid acids or acid salts such as boric acid, its anhydrides, borates, phosphates, sulfites, and acidic metal oxides. As the acidic substance A, among these, one or more selected from boric acid, diboron trioxide, sodium dihydrogen phosphate and sodium hydrogen sulfite are preferable.
　化学発泡剤組成物における、炭酸水素ナトリウムと酸性物質Ａの含有割合は、炭酸水素ナトリウムと酸性物質Ａの合計を１００質量％とした場合に、気泡径を微細化し易い観点から、炭酸水素ナトリウムが５～９０質量％の範囲にあり、酸性物質Ａが９５～１０質量％の範囲にあることが好ましい。より好ましくは、炭酸水素ナトリウムが１０～８５質量％の範囲内であり、酸性物質Ａが９０～１５質量％の範囲内である。さらには好ましくは、炭酸水素ナトリウムが１５～８０質量％の範囲内であり、酸性物質Ａが８５～２０質量％の範囲内である。 The content ratio of sodium hydrogen carbonate and acidic substance A in the chemical blowing agent composition is 100% by mass for the total of sodium hydrogen carbonate and acidic substance A. It is preferably in the range of 5 to 90 mass %, and the acidic substance A is in the range of 95 to 10 mass %. More preferably, sodium hydrogen carbonate is in the range of 10 to 85% by mass, and acidic substance A is in the range of 90 to 15% by mass. More preferably, sodium hydrogen carbonate is in the range of 15 to 80% by mass, and acidic substance A is in the range of 85 to 20% by mass.
（任意成分）
　化学発泡剤組成物は、本発明の効果を損なわない範囲で、任意成分として、例えば、炭酸水素ナトリウム以外のその他の化学発泡剤を含有してもよい。その他の化学発泡剤として、具体的には、アゾジカルボンアミド（ＡＤＣＡ）、Ｐ，Ｐ´－オキシビス（ベンゼンスルホニルヒドラジド）（ＯＢＳＨ）、Ｎ，Ｎ´－ジニトロソペンタメチレンテトラミン、５－フェニル－１，２，３，４－テトラゾールおよび有機酸金属塩等が挙げられる。 (Optional component)
The chemical foaming agent composition may contain other chemical foaming agents other than sodium hydrogencarbonate as optional components within a range that does not impair the effects of the present invention. Other chemical blowing agents specifically include azodicarbonamide (ADCA), P,P'-oxybis(benzenesulfonylhydrazide) (OBSH), N,N'-dinitrosopentamethylenetetramine, 5-phenyl-1 , 2,3,4-tetrazole and organic acid metal salts.
　その他の化学発泡剤の内でも、融点が４００℃未満の有機化学発泡剤（以下、「低融点有機化学発泡剤」ともいう。）については、化学発泡剤組成物中の融点が４００℃未満の有機化合物（以下、「低融点有機化合物」ともいう。）の合計含有量として、５８質量％以下となるように含有されることが好ましい。化学発泡剤組成物は、低融点有機化学発泡剤を含有しないことがより好ましく、その他の化学発泡剤を含有しないことが特に好ましい。 Among other chemical blowing agents, organic chemical blowing agents having a melting point of less than 400°C (hereinafter also referred to as "low-melting organic chemical blowing agents") are It is preferable that the total content of organic compounds (hereinafter also referred to as "low-melting-point organic compounds") is 58% by mass or less. More preferably, the chemical blowing agent composition does not contain low-melting organic chemical blowing agents, and particularly preferably does not contain other chemical blowing agents.
　化学発泡剤組成物は、本発明の効果を損なわない範囲で、任意成分として、例えば、酸性物質Ａ以外の助剤として、酸性物質Ａ以外の発泡助剤、ドリップ防止剤、酸化防止剤、滑剤、分散剤、核剤等のその他の助剤を含有してもよい。 The chemical foaming agent composition may contain optional components, such as auxiliary agents other than acidic substance A, foaming assistants other than acidic substance A, anti-drip agents, antioxidants, lubricants, etc. , dispersants, nucleating agents and the like.
　その他の助剤として、具体的には、タルク、炭酸カルシウム、炭酸リチウム、ホウ酸リチウム等の酸性物質ではない無機化合物が挙げられる。また、クエン酸、クエン酸一ナトリウム等の融点が４００℃未満の有機酸性化合物、ステアリン酸リチウム、酢酸リチウム、シュウ酸リチウム、クエン酸リチウム、シュウ酸ナトリウム、安息香酸ナトリウム等の酸性物質ではない有機化合物が挙げられる。 Specific examples of other auxiliary agents include inorganic compounds that are not acidic substances, such as talc, calcium carbonate, lithium carbonate, and lithium borate. In addition, organic acidic compounds with a melting point of less than 400°C such as citric acid and monosodium citrate, and non-acidic organic compounds such as lithium stearate, lithium acetate, lithium oxalate, lithium citrate, sodium oxalate and sodium benzoate. compound.
　その他の助剤の内でも、融点が４００℃未満の有機発泡助剤（以下、「低融点有機発泡助剤」ともいう。）については、化学発泡剤組成物中の低融点有機化合物の合計含有量として、５８質量％以下となるように含有されることが好ましい。化学発泡剤組成物は、低融点有機発泡助剤を含有しないことがより好ましく、その他の助剤を含有しないことが特に好ましい。 Among other aids, for organic foaming aids with a melting point of less than 400°C (hereinafter also referred to as "low-melting organic foaming aids"), the total content of low-melting organic compounds in the chemical foaming agent composition It is preferably contained in an amount of 58% by mass or less. More preferably, the chemical blowing agent composition does not contain a low-melting organic blowing aid, and particularly preferably does not contain other aids.
　また、上記化合物以外に、後述の発泡材料において、ドリップ防止剤、酸化防止剤、滑剤等の具体例として記載した化合物を、化学発泡剤組成物におけるその他の助剤の具体例とすることができる。化学発泡剤組成物は、これらの発泡助剤以外の助剤を含有する場合についても、化学発泡剤組成物中の低融点有機化合物の合計含有量が５８質量％以下となるように含有することが好ましい。化学発泡剤組成物は、これらの発泡助剤以外の助剤のうちの低融点有機化合物を含有しないことがより好ましく、これらの発泡助剤以外の助剤を含有しないことが特に好ましい。 In addition to the above compounds, the compounds described as specific examples of anti-drip agents, antioxidants, lubricants, etc. in the later-described foaming material can be used as specific examples of other auxiliary agents in the chemical foaming agent composition. . Even when the chemical blowing agent composition contains aids other than these blowing aids, the total content of low-melting organic compounds in the chemical blowing agent composition should be 58% by mass or less. is preferred. It is more preferable that the chemical blowing agent composition does not contain low-melting-point organic compounds among aids other than these foaming aids, and particularly preferably does not contain aids other than these foaming aids.
　以上説明したとおり、本発明の化学発泡剤組成物は、炭酸水素ナトリウム及び酸性物質Ａ以外の成分を含有しないことが好ましい。すなわち、本発明の化学発泡剤組成物は、炭酸水素ナトリウムと酸性物質Ａとからなることが好ましい。 As explained above, the chemical foaming agent composition of the present invention preferably does not contain components other than sodium hydrogen carbonate and acidic substance A. That is, the chemical foaming agent composition of the present invention preferably comprises sodium hydrogen carbonate and acidic substance A.
〔化学発泡剤組成物の形態〕
　本発明の化学発泡剤組成物は、炭酸水素ナトリウム及び酸性物質Ａを混合した混合物、又はこれらの必須成分に任意成分を添加して混合した混合物の形態であってよい。本発明の化学発泡剤組成物は、また、炭酸水素ナトリウム及び酸性物質Ａを別々に準備して、又はこれらの必須成分に加えて任意成分を用いる場合には、当該任意成分をさらに別に準備して、このように別々に準備した各成分を使用時に組み合わせて用いる２成分又は多成分タイプの組成物の形態であってもよい。 [Form of chemical foaming agent composition]
The chemical blowing agent composition of the present invention may be in the form of a mixture of sodium bicarbonate and acidic substance A, or a mixture of these essential ingredients and optional ingredients. In the chemical blowing agent composition of the present invention, the sodium hydrogen carbonate and the acidic substance A are prepared separately, or when optional ingredients are used in addition to these essential ingredients, the optional ingredients are further prepared. Alternatively, it may be in the form of a two-component or multi-component type composition in which each component prepared separately is used in combination at the time of use.
［化学発泡剤マスターバッチ］
　本発明の化学発泡剤マスターバッチは、本発明の化学発泡剤組成物と、熱可塑性樹脂又は熱可塑性エラストマー（樹脂等）とを含有することを特徴とする。 [Chemical Blowing Agent Masterbatch]
The chemical foaming agent masterbatch of the present invention is characterized by containing the chemical foaming agent composition of the present invention and a thermoplastic resin or thermoplastic elastomer (resin or the like).
　本発明の化学発泡剤組成物を用いて発泡体を成形する際には、例えば、当該発泡体のマトリックスを主として構成する樹脂等に化学発泡剤組成物を直接配合することで発泡材料を製造し、当該発泡材料を発泡成形して発泡体とする方法がとられる。なお、上記発泡材料は、本発明の化学発泡剤マスターバッチを樹脂等に配合することで製造されてもよい。 When forming a foam using the chemical foaming agent composition of the present invention, for example, a foam material is produced by directly blending the chemical foaming agent composition into a resin or the like that mainly constitutes the matrix of the foam. , a method of foam-molding the foam material to form a foam. The foam material may be produced by blending the chemical foaming agent masterbatch of the present invention with a resin or the like.
　本発明の化学発泡剤マスターバッチを用いることで、樹脂等に対する化学発泡剤組成物の分散性をより高めた均一な混合がし易くなる。化学発泡剤組成物が均一に分散されることで、気泡の結合等が抑制され、気泡径をより微細なものとすることができる。 By using the chemical foaming agent masterbatch of the present invention, uniform mixing with enhanced dispersibility of the chemical foaming agent composition in the resin or the like can be facilitated. By uniformly dispersing the chemical foaming agent composition, bonding of cells can be suppressed, and the cell diameter can be made finer.
　本発明の化学発泡剤マスターバッチが含有する樹脂等は、後述する発泡体における発泡材料が含有する樹脂等の一部とすることができる。化学発泡剤マスターバッチを用いて成形された発泡体において、化学発泡剤マスターバッチに由来する樹脂等と発泡材料における後添加された樹脂等の合計が発泡体のマトリックスを主として構成する樹脂等である。 The resin or the like contained in the chemical foaming agent masterbatch of the present invention can be part of the resin or the like contained in the foaming material in the foam to be described later. In a foam molded using a chemical foaming agent masterbatch, the sum of the resin etc. derived from the chemical foaming agent masterbatch and the resin etc. added later in the foaming material is the resin etc. which mainly constitutes the matrix of the foam. .
　化学発泡剤マスターバッチにおける樹脂等と後添加される樹脂等の合計量（１００質量％）に対する、化学発泡剤マスターバッチにおける樹脂等の割合をＸ［質量％］とした場合、Ｘ［質量％］は、例えば、１～５質量％が好ましく、２～４質量％がより好ましい。本発明の化学発泡剤マスターバッチにおける化学発泡剤組成物の含有量は、後述の発泡材料における樹脂等の総量に対する化学発泡剤組成物の含有量から計算できる。発泡材料における樹脂等の総量に対する化学発泡剤組成物の含有量をＹ［質量％］とした場合、化学発泡剤マスターバッチにおける化学発泡剤組成物の含有量は、樹脂等の総量に対して、Ｙ／（Ｘ／１００）［質量％］とすることができる。 When the ratio of the resin, etc. in the chemical foaming agent masterbatch to the total amount (100% by mass) of the resin, etc. in the chemical foaming agent masterbatch and the resin etc. added later is X [mass%], X [mass%] is, for example, preferably 1 to 5% by mass, more preferably 2 to 4% by mass. The content of the chemical foaming agent composition in the chemical foaming agent masterbatch of the present invention can be calculated from the content of the chemical foaming agent composition with respect to the total amount of resins and the like in the foaming material described later. When the content of the chemical foaming agent composition with respect to the total amount of resin etc. in the foaming material is Y [% by mass], the content of the chemical foaming agent composition in the chemical foaming agent masterbatch is, with respect to the total amount of resin etc. Y/(X/100) [% by mass].
　なお、発泡体のマトリックスを主として構成する樹脂等として複数の種類の樹脂等を用いる場合、化学発泡剤マスターバッチにおける樹脂等と後添加される樹脂等は同じであっても異なってもよい。 When using a plurality of types of resins, etc. as the resins, etc. that mainly constitute the matrix of the foam, the resins, etc. in the chemical foaming agent masterbatch and the resins, etc. added later may be the same or different.
　本発明の化学発泡剤マスターバッチは、必要に応じてその他の添加剤をさらに含むものであってもよい。その他の添加剤の具体例としては、後述の発泡材料における添加剤と同様の具体例が挙げられる。 The chemical foaming agent masterbatch of the present invention may further contain other additives as necessary. Specific examples of other additives include the same specific examples as the additives in the foamed material described later.
　本発明の化学発泡剤マスターバッチを製造する方法は、特に制限を受けず、例えば、樹脂等と、本発明の化学発泡剤組成物、及び必要に応じて添加されるその他の添加剤をドライブレンドして得られた混合物を化学発泡剤マスターバッチとする方法が挙げられる。 The method for producing the chemical blowing agent masterbatch of the present invention is not particularly limited. The mixture thus obtained is used as a chemical foaming agent masterbatch.
　また、上記で得られた混合物を溶融混練する方法により化学発泡剤マスターバッチとする方法をとってもよい。溶融混錬の際は、炭酸水素ナトリウムの分解、炭酸水素ナトリウムと酸性物質Ａの反応を極力抑える、すなわち発泡を抑えるために次の操作を行ってもよい。例えば、溶融混練物に圧力をかける、溶融混練物の温度を低く設定する、溶融混錬後直ちに冷却する等の操作である。 Alternatively, a method of melting and kneading the mixture obtained above to form a chemical foaming agent masterbatch may be used. During the melt-kneading, the following operations may be performed to suppress the decomposition of sodium hydrogencarbonate and the reaction between sodium hydrogencarbonate and the acidic substance A as much as possible, that is, to suppress foaming. For example, the operations include applying pressure to the melt-kneaded material, setting the temperature of the melt-kneaded material to a low temperature, and cooling the melt-kneaded material immediately after melt-kneading.
［発泡体］
　本発明の発泡体は、本発明の化学発泡剤組成物又は本発明の化学発泡剤マスターバッチと、熱可塑性樹脂又は熱可塑性エラストマーとを含有する発泡材料を発泡成形したことを特徴とする発泡体である。 [Foam]
The foam of the present invention is obtained by foam-molding a foam material containing the chemical foaming agent composition of the present invention or the chemical foaming agent masterbatch of the present invention and a thermoplastic resin or thermoplastic elastomer. is.
　「発泡材料」は、熱可塑性樹脂又は熱可塑性エラストマーに化学発泡剤、化学発泡剤組成物又は化学発泡マスターバッチを混ぜ合わせた組成物である。「発泡体」は、熱可塑性樹脂又は熱可塑性エラストマーに化学発泡剤、化学発泡剤組成物又は化学発泡剤マスターバッチを混ぜ合わせた組成物を所定の形状に発泡成形した成形体である。発泡材料を所定の形状に発泡成形した成形体と言ってもよい。 A "foaming material" is a composition in which a thermoplastic resin or thermoplastic elastomer is mixed with a chemical foaming agent, a chemical foaming agent composition, or a chemical foaming masterbatch. A "foam" is a molded article obtained by foam-molding a composition obtained by mixing a thermoplastic resin or thermoplastic elastomer with a chemical foaming agent, a chemical foaming agent composition, or a chemical foaming agent masterbatch into a predetermined shape. It may also be said that it is a molded product obtained by foam-molding a foam material into a predetermined shape.
　本発明に係る発泡材料は、本発明の化学発泡剤組成物又は本発明の化学発泡剤マスターバッチと、熱可塑性樹脂又は熱可塑性エラストマーとを含有する組成物である。本発明の発泡体は、本発明に係る発泡材料を所定の形状に発泡成形した成形体である。 The foaming material according to the present invention is a composition containing the chemical foaming agent composition of the present invention or the chemical foaming agent masterbatch of the present invention and a thermoplastic resin or thermoplastic elastomer. The foam of the present invention is a molded article obtained by foam-molding the foam material of the present invention into a predetermined shape.
〔発泡材料〕
　本発明の発泡体を得るための発泡材料は、本発明の化学発泡剤組成物又は本発明の化学発泡剤マスターバッチと、熱可塑性樹脂又は熱可塑性エラストマー（樹脂等）とを含有する。 [Foam material]
The foaming material for obtaining the foam of the present invention contains the chemical foaming agent composition of the present invention or the chemical foaming agent masterbatch of the present invention and a thermoplastic resin or thermoplastic elastomer (resin or the like).
　発泡材料は、上記のとおり、本発明の発泡体のマトリックスを主として構成する樹脂等に化学発泡剤組成物を直接配合して製造されてもよく、本発明の化学発泡剤マスターバッチを樹脂等に配合することで製造されてもよい。発泡材料に本発明の化学発泡剤マスターバッチを用いる場合、発泡材料が含有する樹脂等は、本発明の化学発泡剤マスターバッチが含有する樹脂等と後添加される樹脂等の合計である。 As described above, the foam material may be produced by directly blending the chemical foaming agent composition into the resin or the like that mainly constitutes the matrix of the foam of the present invention. It may be produced by compounding. When the chemical foaming agent masterbatch of the present invention is used for the foaming material, the resins and the like contained in the foaming material are the sum of the resins and the like contained in the chemical foaming agent masterbatch of the present invention and the resins and the like added later.
　発泡材料が含有する樹脂等としては、通常、発泡体成形に用いられる熱可塑性樹脂又は熱可塑性エラストマーであれば、特に制限なく用いることができる。すなわち、本発明の発泡体によれば、本発明の化学発泡剤組成物を用いることで、上に説明した作用効果により気泡の微細化と難燃性低下の抑制ができる。したがって、本発明の発泡体によれば、本発明の化学発泡剤組成物を用いることで、熱可塑性樹脂及び熱可塑性エラストマーの種類によらず、どの種類の熱可塑性樹脂及び熱可塑性エラストマーを使用しても同様に気泡の微細化と難燃性低下の抑制ができる。 As the resin or the like contained in the foam material, any thermoplastic resin or thermoplastic elastomer normally used for foam molding can be used without particular limitation. That is, according to the foam of the present invention, by using the chemical foaming agent composition of the present invention, it is possible to miniaturize cells and suppress deterioration of flame retardancy due to the effects described above. Therefore, according to the foam of the present invention, by using the chemical blowing agent composition of the present invention, it is possible to use any kind of thermoplastic resin and thermoplastic elastomer regardless of the kind of thermoplastic resin and thermoplastic elastomer. Similarly, microbubbles can be made finer and flame retardancy can be suppressed.
　なお、以下にも説明するが、発泡材料が含有する熱可塑性樹脂又は熱可塑性エラストマーは、特に制限されないが、ポリオレフィン樹脂、アクリロニトリル－ブタジエン－スチレン樹脂（ＡＢＳ樹脂）、ポリスチレン樹脂、ポリアミド樹脂、ポリ塩化ビニル樹脂、エチレン酢酸ビニル樹脂及び熱可塑性エラストマーから選ばれる少なくとも１種を含むことが好ましい。 As described below, the thermoplastic resin or thermoplastic elastomer contained in the foam material is not particularly limited, but polyolefin resin, acrylonitrile-butadiene-styrene resin (ABS resin), polystyrene resin, polyamide resin, polychlorinated It preferably contains at least one selected from vinyl resins, ethylene vinyl acetate resins and thermoplastic elastomers.
（熱可塑性樹脂）
　熱可塑性樹脂として、具体的には、ポリオレフィン樹脂、ポリスチレン樹脂、ポリアミド樹脂、ポリイミド樹脂、ポリエステル樹脂、アクリル樹脂、ポリウレタン樹脂、ポリ塩化ビニル樹脂、酢酸ビニル樹脂、エチレン酢酸ビニル樹脂、エポキシ樹脂、フェノール樹脂、メラミン樹脂、ポリカーボネート樹脂、ポリアセタール樹脂、ポリフェニレンエーテル樹脂、ポリフェニレンスルファイド樹脂、ポリスルホン樹脂、スチレン－アクリロニトリル樹脂（ＡＳ樹脂）、スチレン－（メタ）アクリル酸樹脂、スチレン－メタクリル酸メチル樹脂、アクリロニトリル－ブタジエン－スチレン樹脂（ＡＢＳ樹脂）、メタクリル酸メチル－ブタジエン－スチレン樹脂（ＭＢＳ樹脂）等が挙げられる。 (Thermoplastic resin)
Specific examples of thermoplastic resins include polyolefin resins, polystyrene resins, polyamide resins, polyimide resins, polyester resins, acrylic resins, polyurethane resins, polyvinyl chloride resins, vinyl acetate resins, ethylene vinyl acetate resins, epoxy resins, and phenol resins. , melamine resin, polycarbonate resin, polyacetal resin, polyphenylene ether resin, polyphenylene sulfide resin, polysulfone resin, styrene-acrylonitrile resin (AS resin), styrene-(meth)acrylic acid resin, styrene-methyl methacrylate resin, acrylonitrile-butadiene -Styrene resin (ABS resin), methyl methacrylate-butadiene-styrene resin (MBS resin), and the like.
　これらのうちでも、本発明の発泡体に用いる熱可塑性樹脂としては、ポリオレフィン樹脂、ＡＢＳ樹脂、ポリスチレン樹脂、ポリアミド樹脂、ポリ塩化ビニル樹脂及びエチレン酢酸ビニル樹脂等が好ましい。 Among these, polyolefin resins, ABS resins, polystyrene resins, polyamide resins, polyvinyl chloride resins, ethylene vinyl acetate resins, and the like are preferable as the thermoplastic resins used for the foam of the present invention.
＜ポリオレフィン樹脂＞
　ポリオレフィン樹脂は、オレフィンを単量体成分の主成分として重合された単独重合体又は共重合体である。なお、本明細書において、「オレフィン」は、二重結合を１つ有する脂肪族鎖式不飽和炭化水素をいう。 <Polyolefin resin>
Polyolefin resins are homopolymers or copolymers polymerized with olefin as the main monomer component. In addition, in this specification, "olefin" means the aliphatic chain type unsaturated hydrocarbon which has one double bond.
　ここで、樹脂（重合体）を構成する主成分とは、重合体を構成する全単量体成分中、５０質量％以上である成分をいう。ポリオレフィン樹脂は、オレフィンを全単量体成分中、好ましくは６０～１００質量％、より好ましくは７０～１００質量％、さらに好ましくは８０～１００質量％含んでなる単独重合体又は共重合体である。 Here, the main component that constitutes the resin (polymer) refers to a component that accounts for 50% by mass or more of the total monomer components that constitute the polymer. The polyolefin resin is a homopolymer or copolymer containing olefin in an amount of preferably 60 to 100% by mass, more preferably 70 to 100% by mass, and still more preferably 80 to 100% by mass in the total monomer components. .
　オレフィン共重合体には、オレフィンと他のオレフィンとの共重合体、又はオレフィンとオレフィンに共重合可能な他の単量体との共重合体が含まれる。ポリオレフィン樹脂における上記他の単量体の含有量は、全単量体成分中、好ましくは３０質量％以下、より好ましくは０～２０質量％である。 Olefin copolymers include copolymers of olefins with other olefins, or copolymers of olefins with other monomers that can be copolymerized with olefins. The content of the other monomers in the polyolefin resin is preferably 30% by mass or less, more preferably 0 to 20% by mass, based on the total monomer components.
　オレフィンとしては、炭素数２～１２のα－オレフィンが好ましい。オレフィンとしては、例えば、エチレン、プロピレン、１－ブテン、イソブテン、１－ペンテン、３－メチル－１－ブテン、１－ヘキセン、１－オクテン、及び１－デセン等を挙げることができる。ポリオレフィン樹脂の重合に際して、オレフィンは、１種を単独で用いてもよく、２種以上を併用してもよい。 As the olefin, an α-olefin having 2 to 12 carbon atoms is preferable. Examples of olefins include ethylene, propylene, 1-butene, isobutene, 1-pentene, 3-methyl-1-butene, 1-hexene, 1-octene, and 1-decene. When polymerizing the polyolefin resin, the olefins may be used singly or in combination of two or more.
　オレフィンに共重合可能な他の単量体としては、例えば、シクロペンテン及びノルボルネン等の環状オレフィン、並びに１，４－ヘキサジエン及び５－エチリデン－２－ノルボルネン等のジエン等を挙げることができる。さらに、酢酸ビニル、スチレン、（メタ）アクリル酸及びその誘導体、ビニルエーテル、無水マレイン酸、一酸化炭素、Ｎ－ビニルカルバゾール等の単量体を用いてもよい。上記他の単量体は、ポリオレフィン樹脂の重合に際して、１種を単独で用いてもよく、２種以上を併用してもよい。なお、「（メタ）アクリル酸」は、アクリル酸及びメタクリル酸の少なくとも一方を意味する。 Examples of other monomers copolymerizable with olefins include cyclic olefins such as cyclopentene and norbornene, and dienes such as 1,4-hexadiene and 5-ethylidene-2-norbornene. Furthermore, monomers such as vinyl acetate, styrene, (meth)acrylic acid and its derivatives, vinyl ether, maleic anhydride, carbon monoxide, and N-vinylcarbazole may be used. These other monomers may be used singly or in combination of two or more in the polymerization of the polyolefin resin. In addition, "(meth)acrylic acid" means at least one of acrylic acid and methacrylic acid.
　ポリオレフィン樹脂の具体例としては、高密度ポリエチレン（ＨＤＰＥ）、低密度ポリエチレン（ＬＤＰＥ）、及び直鎖状低密度ポリエチレン（ＬＬＤＰＥ）等のエチレンを主成分とするポリエチレン樹脂；ポリプロピレン（プロピレン単独重合体）、エチレン－プロピレン共重合体、プロピレン－ブテン共重合体、エチレン－プロピレン－ブテン共重合体、及びエチレン－プロピレン－ジエン共重合体等のプロピレンを主成分とするポリプロピレン樹脂；ポリブテン；並びにポリペンテン等を挙げることができる。 Specific examples of polyolefin resins include polyethylene resins containing ethylene as a main component, such as high-density polyethylene (HDPE), low-density polyethylene (LDPE), and linear low-density polyethylene (LLDPE); polypropylene (propylene homopolymer); , ethylene-propylene copolymers, propylene-butene copolymers, ethylene-propylene-butene copolymers, and ethylene-propylene-diene copolymers. can be mentioned.
　ポリオレフィン樹脂としては、ポリエチレン樹脂及びポリプロピレン樹脂が好ましく、ポリプロピレン樹脂がより好ましい。ポリプロピレン樹脂におけるプロピレンに由来する構造の立体規則性は、アイソタクチック、シンジオタクチック、及びアタクチックのいずれでもよい。ポリプロピレン樹脂としては、ポリプロピレンがさらに好ましい。 As the polyolefin resin, polyethylene resin and polypropylene resin are preferable, and polypropylene resin is more preferable. The stereoregularity of the structure derived from propylene in the polypropylene resin may be isotactic, syndiotactic, or atactic. Polypropylene is more preferable as the polypropylene resin.
＜ポリスチレン樹脂＞
　ポリスチレン樹脂は、スチレン系単量体を単量体成分の主成分として重合された単独重合体又は共重合体である。スチレン系単量体としては、例えば、スチレン、α－メチルスチレン、ビニルトルエン、クロロスチレン、エチルスチレン、ｉ－プロピルスチレン、ジメチルスチレン、ブロモスチレン等が挙げられる。 <Polystyrene resin>
A polystyrene resin is a homopolymer or copolymer polymerized with a styrene-based monomer as the main monomer component. Styrenic monomers include, for example, styrene, α-methylstyrene, vinyltoluene, chlorostyrene, ethylstyrene, i-propylstyrene, dimethylstyrene, bromostyrene and the like.
　ポリスチレン樹脂としては、スチレンを主成分とする、すなわち、スチレンを５０質量％以上含有するポリスチレン樹脂が好ましく、ポリスチレン（スチレン単独重合体）がより好ましい。 As the polystyrene resin, a polystyrene resin containing styrene as a main component, that is, containing 50% by mass or more of styrene is preferable, and polystyrene (styrene homopolymer) is more preferable.
　ポリスチレン樹脂としては、スチレン系単量体を主成分とする、スチレン系単量体とこのスチレン系単量体と共重合可能なビニル単量体との共重合体であってもよい。このようなビニル単量体としては、例えば、メチル（メタ）アクリレート、エチル（メタ）アクリレート、ブチル（メタ）アクリレート、セチル（メタ）アクリレート等のアルキル（メタ）アクリレート、（メタ）アクリロニトリル、ジメチルマレエート、ジメチルフマレート、ジエチルフマレート、エチルフマレートの他、ジビニルベンゼン、アルキレングリコールジメタクリレートなどの二官能性単量体等が挙げられる。 The polystyrene resin may be a copolymer of a styrene-based monomer and a vinyl monomer copolymerizable with the styrene-based monomer, the main component of which is a styrene-based monomer. Examples of such vinyl monomers include alkyl (meth)acrylates such as methyl (meth)acrylate, ethyl (meth)acrylate, butyl (meth)acrylate, and cetyl (meth)acrylate; (meth)acrylonitrile; ate, dimethyl fumarate, diethyl fumarate, ethyl fumarate, divinylbenzene, alkylene glycol dimethacrylate, and other bifunctional monomers.
＜ＡＢＳ樹脂＞
　ＡＢＳ樹脂（アクリロニトリル－ブタジエン－スチレン樹脂）は、ポリブタジエン（ＢＲ）、スチレン－ブタジエン共重合体（ＳＢＲ）等のゴムにスチレン及びアクリロニトリルがグラフト重合した構造を有する熱可塑性樹脂である。 <ABS resin>
ABS resin (acrylonitrile-butadiene-styrene resin) is a thermoplastic resin having a structure in which styrene and acrylonitrile are graft polymerized to rubber such as polybutadiene (BR) and styrene-butadiene copolymer (SBR).
　ＡＢＳ樹脂は、ゴムとＡＳ樹脂を機械的に混合するブレンド法でも製造できるが、製品品質の均一性の観点から、ゴムの存在下にスチレン及びアクリロニトリルを重合させるグラフト法及びグラフト法で得られた重合体とＡＳ樹脂を混合するグラフト－ブレンド法で得られるＡＢＳ樹脂が好ましい。 ABS resin can also be produced by a blending method in which rubber and AS resin are mechanically mixed. An ABS resin obtained by a graft-blending method of mixing a polymer and an AS resin is preferred.
　ＡＢＳ樹脂において、例えば、耐熱性を向上させる目的でスチレンの一部をα－メチルスチレンで置き替えることが可能である。また、ＡＢＳ樹脂において、ＡＳ樹脂相にメタクリル酸メチルを導入することも可能である。 In ABS resin, for example, part of styrene can be replaced with α-methylstyrene for the purpose of improving heat resistance. In ABS resins, it is also possible to introduce methyl methacrylate into the AS resin phase.
＜ポリアミド樹脂＞
　ポリアミド樹脂としては、例えば、脂肪族、芳香族、及び脂肪－芳香族ポリアミド単独重合体、脂肪族及び芳香族ポリアミド共重合体及びそれらの混合物が挙げられる。 <Polyamide resin>
Polyamide resins include, for example, aliphatic, aromatic, and aliphatic-aromatic polyamide homopolymers, aliphatic and aromatic polyamide copolymers, and mixtures thereof.
　ポリアミド単独重合体には、具体的には、ポリヘキサメチレンアジパミド（ポリアミド６６）、ポリヘキサメチレンアゼラアミド（ポリアミド６９）、ポリヘキサメチレンセバカミド（ポリアミド６１０）、ポリヘキサメチレンドデカンジアミド（ポリアミド６１２）、ポリテトラメチレンアジパミド（ポリアミド４６）、ポリドデカンメチレンドデカンアミド（ポリアミド１２１２）、ポリシクラミドＱ２（ポリアミドＣ８）等が含まれる。 Polyamide homopolymers specifically include polyhexamethyleneadipamide (polyamide 66), polyhexamethyleneazelaamide (polyamide 69), polyhexamethylenesebacamide (polyamide 610), polyhexamethylenedodecanediamide (polyamide 612), polytetramethylene adipamide (polyamide 46), polydodecanmethylenedodecanamide (polyamide 1212), polycyclamide Q2 (polyamide C8), and the like.
　ポリアミド単独重合体には、さらに、ポリカプロラクタム（ポリアミド６）、ポリラウロラクタム（ポリアミド１２）、ポリ－１１－アミノウンデカン酸（ポリアミド１１）及びジ（ｐ－アミノシクロヘキシル）メタンドデカンジアミド等のラクタムの開環により調製されるポリアミド等が含まれる。また、ポリキシリレンアジパミド（ポリアミドＭＸＤ６）、ポリトリメチルヘキサメチレンテレフタルアミド（ポリアミド６－３－Ｔ）、ポリヘキサメチレンジアミンテレフタルアミド（ポリアミド６Ｔ）及びポリヘキサメチレンイソフタルアミド（ポリアミド６Ｉ）等の芳香族ポリアミドも含まれる。 Polyamide homopolymers further include lactams such as polycaprolactam (polyamide 6), polylaurolactam (polyamide 12), poly-11-aminoundecanoic acid (polyamide 11) and di(p-aminocyclohexyl)methandodecanediamide. Polyamides and the like prepared by ring opening are included. In addition, polyxylylene adipamide (polyamide MXD6), polytrimethylhexamethylene terephthalamide (polyamide 6-3-T), polyhexamethylenediamine terephthalamide (polyamide 6T) and polyhexamethylene isophthalamide (polyamide 6I), etc. Also included are aromatic polyamides.
　脂肪族及び芳香族ポリアミド共重合体としては、少なくとも２種の上記ポリマー又はそれらの構成成分の共重合により調製されるポリアミドが挙げられる。これらの共重合体として、具体的には、ポリアミド６／６６共重合体、ポリアミド６／１２共重合体、ポリアミド６／６Ｔ共重合体、ポリアミド６Ｉ／６Ｔ共重合体等が挙げられる。 Aliphatic and aromatic polyamide copolymers include polyamides prepared by copolymerization of at least two of the above polymers or their constituents. Specific examples of these copolymers include polyamide 6/66 copolymer, polyamide 6/12 copolymer, polyamide 6/6T copolymer, and polyamide 6I/6T copolymer.
　本発明の発泡体に用いる熱可塑性樹脂としては、上記に挙げた熱可塑性樹脂の１種を単独で用いてもよく、２種類以上を組み合わせて用いてもよい。例えば、ポリスチレン樹脂を主成分として、ポリスチレン樹脂とその他の樹脂を組み合わせて用いてもよい。その場合のその他の樹脂としては、ポリエチレン樹脂、ポリプロピレン樹脂、アクリル樹脂、ＡＳ樹脂、ＡＢＳ樹脂等が好ましい。 As the thermoplastic resin used for the foam of the present invention, one of the thermoplastic resins listed above may be used alone, or two or more of them may be used in combination. For example, a polystyrene resin may be used as a main component, and a combination of the polystyrene resin and other resins may be used. As other resins in that case, polyethylene resins, polypropylene resins, acrylic resins, AS resins, ABS resins and the like are preferable.
（熱可塑性エラストマー）
　熱可塑性エラストマーは、使用温度では加硫されたゴムと同様の性質を持つが、昇温されると熱可塑性樹脂と同様に成形することができ、また、再成形することができるポリマー又はポリマーブレンドからなるものである。本発明においては、樹脂等として、上記熱可塑性樹脂におけるポリオレフィン樹脂、ＡＢＳ樹脂、ポリスチレン樹脂、ポリアミド樹脂、ポリ塩化ビニル樹脂及びエチレン酢酸ビニル樹脂と同様に、熱可塑性エラストマーが好ましい。 (thermoplastic elastomer)
Thermoplastic elastomers are polymers or polymer blends that have properties similar to vulcanized rubber at the temperature of use, but can be molded and remolded like thermoplastics at elevated temperatures. It consists of In the present invention, thermoplastic elastomers are preferred as resins and the like, as with polyolefin resins, ABS resins, polystyrene resins, polyamide resins, polyvinyl chloride resins, and ethylene vinyl acetate resins in the above thermoplastic resins.
　熱可塑性エラストマーは、材料内に、柔軟性成分（ゴム相またはソフトセグメント）と分子拘束成分（樹脂相またはハードセグメント）の両者を含有する。上記ソフトセグメントには各種原料ゴムの化学的組成や構造が採用でき、ハードセグメントには種々の樹脂成分が適用される。熱可塑性エラストマーは、ハードセグメントの化学的組成によって分類するのが一般的である。 Thermoplastic elastomers contain both a flexible component (rubber phase or soft segment) and a molecularly constrained component (resin phase or hard segment) within the material. The chemical composition and structure of various raw rubbers can be adopted for the soft segment, and various resin components are applied for the hard segment. Thermoplastic elastomers are generally classified according to the chemical composition of the hard segments.
　このようにして分類された熱可塑性エラストマーとしては、スチレン系エラストマー、塩素化ポリエチレン、塩ビ系エラストマー、オレフィン系エラストマー、ウレタン系エラストマー、エステル系エラストマー、アミド系エラストマー、アイオノマー等が挙げられる。 Thermoplastic elastomers classified in this way include styrene elastomers, chlorinated polyethylene, vinyl chloride elastomers, olefin elastomers, urethane elastomers, ester elastomers, amide elastomers, and ionomers.
　スチレン系エラストマーとしては、スチレンとブタジエン又はイソプレンとのブロックコポリマー（ＳＢＳ又はＳＩＳ）とその水素添加（水添）ポリマー（ＳＥＢＳ又はＳＥＰＳ）等が挙げられる。また、スチレン系エラストマーには、ポリスチレン樹脂に、ポリブタジエン（ＢＲ）、スチレン－ブタジエン共重合体（ＳＢＲ）、エチレン－プロピレン－非共役ジエン三次元共重合体などのジエン系のゴム状重合体を添加したハイインパクトポリスチレン（ＨＩＰＳ）が含まれる。 Styrenic elastomers include block copolymers of styrene and butadiene or isoprene (SBS or SIS) and their hydrogenated (hydrogenated) polymers (SEBS or SEPS). For styrene-based elastomers, diene-based rubber-like polymers such as polybutadiene (BR), styrene-butadiene copolymer (SBR), and ethylene-propylene-nonconjugated diene three-dimensional copolymer are added to polystyrene resin. and high impact polystyrene (HIPS).
　塩ビ系エラストマーとしては、高重合度のポリ塩化ビニル（ＰＶＣ）と可塑剤とのブレンド、ＰＶＣ合成時に架橋構造を付与した部分架橋ＰＶＣと可塑化ＰＶＣのブレンド、ＰＶＣとアクリロニトリル－ブタジエンゴム（ＮＢＲ）やウレタンゴムとのブレンド品が挙げられる。 Examples of PVC-based elastomers include a blend of polyvinyl chloride (PVC) with a high degree of polymerization and a plasticizer, a blend of partially crosslinked PVC to which a crosslinked structure is imparted during PVC synthesis and plasticized PVC, and PVC and acrylonitrile-butadiene rubber (NBR). and blended products with urethane rubber.
　オレフィン系エラストマーとしては、ポリオレフィン、好ましくはポリプロピレンと、ゴム、例えば、エチレン－プロピレンゴム（ＥＰＭ）、エチレン－プロピレン－ジエンゴム（ＥＰＤＭ）、イソブチレン－イソプレンゴム（ＩＩＲ）、天然ゴム（ＮＲ）、ＮＢＲ等との単純ブレンド品、ポリオレフィンとゴムを混合する際にゴムに加硫をかけてポリオレフィン中に架橋ゴム粒子を細かく分散させた動的加硫タイプ等が挙げられる。 The olefinic elastomers include polyolefins, preferably polypropylene, and rubbers such as ethylene-propylene rubber (EPM), ethylene-propylene-diene rubber (EPDM), isobutylene-isoprene rubber (IIR), natural rubber (NR), NBR and the like. A dynamic vulcanization type in which crosslinked rubber particles are finely dispersed in polyolefin by vulcanizing rubber when mixing polyolefin and rubber.
　ウレタン系エラストマーとしては、ハードセグメントがポリウレタンであり、ソフトセグメントが脂肪族ポリエーテル又はポリエステルであるブロックコポリマーが適用できる。エステル系エラストマーとしては、ハードセグメントが芳香族ポリエステルであり、ソフトセグメントが脂肪族ポリエーテル又はポリエステルであるブロックコポリマーが適用できる。アミド系エラストマーとしては、ハードセグメントが脂肪族ポリアミド（ポリアミド１２、１１が主）、ソフトセグメントが脂肪族ポリエーテルあるいはポリエステルからなるブロックコポリマーが適用できる。 As the urethane-based elastomer, a block copolymer in which the hard segment is polyurethane and the soft segment is aliphatic polyether or polyester can be applied. As the ester-based elastomer, a block copolymer having an aromatic polyester hard segment and an aliphatic polyether or polyester soft segment can be applied. As the amide elastomer, a block copolymer having an aliphatic polyamide (mainly polyamide 12 and 11) as the hard segment and an aliphatic polyether or polyester as the soft segment can be applied.
　本発明の発泡材料が含有する熱可塑性樹脂又は熱可塑性エラストマーは、上記熱可塑性樹脂及び熱可塑性エラストマーから選ばれる１種が単独で用いられてもよく、２種以上が併用されてもよい。 As for the thermoplastic resin or thermoplastic elastomer contained in the foamed material of the present invention, one selected from the above thermoplastic resins and thermoplastic elastomers may be used alone, or two or more thereof may be used in combination.
（発泡材料の組成）
　本発明に係る発泡材料は、本発明の化学発泡剤組成物を、発泡材料中の熱可塑性樹脂及び熱可塑性エラストマー（樹脂等）の総量に対して、０．１～１．７質量％の範囲で含有することが好ましく、０．２～０．５質量％の範囲で含有することがより好ましい。 (Composition of foam material)
The foaming material according to the present invention contains the chemical foaming agent composition of the present invention in the range of 0.1 to 1.7% by mass with respect to the total amount of the thermoplastic resin and thermoplastic elastomer (resin etc.) in the foaming material. is preferably contained in the range of 0.2 to 0.5% by mass.
　また、発泡材料の全量に対する、化学発泡剤組成物に由来する融点が４００℃未満の有機化合物の含有割合は、１質量％以下の範囲内であることが好ましく、０．３質量％以下であることがより好ましく、０質量％である、すなわち含有しないことが特に好ましい。 In addition, the content of the organic compound having a melting point of less than 400° C. derived from the chemical foaming agent composition, relative to the total amount of the foaming material, is preferably within the range of 1% by mass or less, and is 0.3% by mass or less. is more preferable, and it is particularly preferable that it is 0% by mass, that is, it does not contain.
　これにより、上記発泡材料を用いて得られる本発明の発泡体における、化学発泡剤組成物に由来する融点が４００℃未満の有機化合物の含有割合を１質量％以下、さらには０．３質量％以下、特には０質量％とすることができる。また、これにより、上記発泡材料を用いて得られる本発明の発泡体において、化学発泡剤組成物を含有しない場合の樹脂等から、化学発泡剤組成物を用いて発泡体とすることで、難燃性が低下することを抑制することができる。 As a result, in the foam of the present invention obtained using the foaming material, the content of the organic compound having a melting point of less than 400° C. derived from the chemical foaming agent composition is 1% by mass or less, further 0.3% by mass. Hereafter, it can be set to 0 mass % especially. In addition, in the foam of the present invention obtained using the above foaming material, by using a chemical foaming agent composition to form a foam from a resin or the like that does not contain a chemical foaming agent composition, it is difficult to A decrease in combustibility can be suppressed.
　本発明に係る発泡材料は、熱可塑性樹脂又は熱可塑性エラストマーの種類に応じて、任意成分として難燃剤を含有することが好ましい。発泡材料に難燃剤を添加するか否かは、例えば、後述する難燃性の評価において、樹脂等の燃焼時間を指標として適宜選択される。難燃剤の添加なしに難燃性を有する樹脂等としては、例えば、ポリアミド樹脂が挙げられる。 The foam material according to the present invention preferably contains a flame retardant as an optional component depending on the type of thermoplastic resin or thermoplastic elastomer. Whether or not to add a flame retardant to the foam material is appropriately selected, for example, in the evaluation of flame retardancy described later, using the burning time of the resin or the like as an index. Examples of resins having flame retardancy without the addition of flame retardants include polyamide resins.
（難燃剤）
　難燃剤としては、臭素系難燃剤、リン系難燃剤、及び、例えば、アンチモン化合物や金属水酸化物等の無機系難燃剤等が挙げられる。難燃剤は、１種を単独で用いてもよく、２種以上を併用してもよい。 (Flame retardants)
Examples of flame retardants include brominated flame retardants, phosphorus flame retardants, and inorganic flame retardants such as antimony compounds and metal hydroxides. A flame retardant may be used individually by 1 type, and may use 2 or more types together.
＜臭素系難燃剤＞
　臭素系難燃剤としては、テトラブロモビスフェノールＡ（ＴＢＢＡ）、デカブロモジフェニルエーテル（Ｄｅｃａ－ＢＤＥ）、トリブロモフェノール、ヘキサブロモシクロドデカン（ＨＢＣＤ）、エチレンビス（テトラブロモフタルイミド）、ＴＢＢＡカーボネート・オリゴマー、ＴＢＢＡエポキシ・オリゴマー、臭素化ポリスチレン、ビス（ペンタブロモフェニル）エタン、ＴＢＢＡ－ビス（ジブロモプロピルエーテル）、ポリ（ジブロモフェノール）、ヘキサブロモベンゼン（ＨＢＢ）等が挙げられる。 <Brominated flame retardant>
Brominated flame retardants include tetrabromobisphenol A (TBBA), decabromodiphenyl ether (Deca-BDE), tribromophenol, hexabromocyclododecane (HBCD), ethylenebis(tetrabromophthalimide), TBBA carbonate oligomer, TBBA Epoxy oligomers, brominated polystyrene, bis(pentabromophenyl)ethane, TBBA-bis(dibromopropyl ether), poly(dibromophenol), hexabromobenzene (HBB), and the like.
　臭素系難燃剤としては、ビス（ヒドロキシフェニル）スルホン誘導体、ビス（アルコキシフェニル）スルホン誘導体等を用いてもよい。具体的には、ビス［３，５－ジブロモ－４－（２，３－ジブロモプロポキシ）フェニル］スルホン等が挙げられる。 As the brominated flame retardant, bis(hydroxyphenyl)sulfone derivatives, bis(alkoxyphenyl)sulfone derivatives, etc. may be used. Specific examples include bis[3,5-dibromo-4-(2,3-dibromopropoxy)phenyl]sulfone.
　なお、臭素系難燃剤のうちでも、燃焼時に樹脂等の滴下（ドリップ）を防止する、ノンドリップタイプの臭素系難燃剤として、例えば、ビス（ペンタブロモフェニル）エタン等が挙げられる。なお、ドリップタイプの臭素系難燃剤を用いる場合には、後述のドリップ防止剤を併用してもよい。 Among the brominated flame retardants, non-drip type brominated flame retardants that prevent resin from dripping during combustion include, for example, bis(pentabromophenyl)ethane. When a drip-type brominated flame retardant is used, an anti-drip agent, which will be described later, may be used in combination.
＜リン系難燃剤＞
　リン系難燃剤としては、有機リン系難燃剤であっても無機リン系難燃剤であってもよい。有機リン系難燃剤としては、例えば、有機リン酸エステルが挙げられる。有機リン酸エステルとしては、亜リン酸エステル、リン酸エステルおよびホスホン酸エステルなどのリン酸エステル化合物が挙げられ、これらの中でも、特にリン酸エステルを用いることが好ましい。無機リン系難燃剤の場合、高分子量の無機リン系化合物が好ましく、例えば、ポリリン酸アンモニウム及びその誘導体等が挙げられる。 <Phosphorus flame retardant>
The phosphorus-based flame retardant may be an organic phosphorus-based flame retardant or an inorganic phosphorus-based flame retardant. Organic phosphorus flame retardants include, for example, organic phosphoric acid esters. Examples of organic phosphates include phosphate compounds such as phosphites, phosphates and phosphonates. Among these, it is particularly preferable to use phosphates. In the case of the inorganic phosphorus-based flame retardant, a high-molecular-weight inorganic phosphorus-based compound is preferable, and examples thereof include ammonium polyphosphate and derivatives thereof.
　亜リン酸エステルの具体例としては、トリフェニルホスファイト、トリス（ノニルフェニル）ホスファイト、トリス（２，４－ジ－ｔ－ブチルフェニル）ホスファイト、ジステアリルペンタエリスリトールジホスファイト、ビス（２，６－ジ－ｔ－ブチル－４－メチルフェニル）ペンタエリスリトールジホスファイト、ビス（２，４－ジ－ｔ－ブチルフェニル）ペンタエリスリトールジホスファイトなどが挙げられる。 Specific examples of phosphites include triphenylphosphite, tris(nonylphenyl)phosphite, tris(2,4-di-t-butylphenyl)phosphite, distearylpentaerythritol diphosphite, bis(2 ,6-di-t-butyl-4-methylphenyl)pentaerythritol diphosphite, bis(2,4-di-t-butylphenyl)pentaerythritol diphosphite and the like.
　リン酸エステルの具体例としては、トリフェニルホスフェート、トリス（ノニルフェニル）ホスフェート、トリス（２，４－ジ－ｔ－ブチルフェニル）ホスフェート、ジステアリルペンタエリスリトールジホスフェート、ビス（２，６－ジ－ｔ－ブチル－４－メチルフェニル）ペンタエリスリトールジホスフェート、ビス（２，４－ジ－ｔ－ブチルフェニル）ペンタエリスリトールジホスフェート、トリブチルホスフェート、ビスフェノールＡビス－ジフェニルホスフェート、芳香族縮合リン酸エステルなどが挙げられる。 Specific examples of phosphate esters include triphenyl phosphate, tris(nonylphenyl) phosphate, tris(2,4-di-t-butylphenyl) phosphate, distearylpentaerythritol diphosphate, bis(2,6-di- t-butyl-4-methylphenyl)pentaerythritol diphosphate, bis(2,4-di-t-butylphenyl)pentaerythritol diphosphate, tributyl phosphate, bisphenol A bis-diphenyl phosphate, aromatic condensed phosphate ester, etc. mentioned.
　芳香族縮合リン酸エステルとしては、例えば、１，３－フェニレンビス（ジ２，６キシレニルホスフェート）、ビスフェノールＡビス（ジフェニルホスフェート）及び１，３－フェニレンビス（ジフェニルホスフェート）などが挙げられる。 Examples of aromatic condensed phosphate esters include 1,3-phenylene bis(di-2,6 xylenyl phosphate), bisphenol A bis(diphenyl phosphate) and 1,3-phenylene bis(diphenyl phosphate). .
　ホスホン酸エステルの具体例としては、ベンゼンホスホン酸ジメチル、ベンゼンホスホン酸エステルなどが挙げられる。 Specific examples of phosphonate include dimethyl benzenephosphonate and benzenephosphonate.
　本発明に係る発泡材料における難燃剤の含有量は、樹脂等の総量に対して１～３０質量％の範囲内にあることが好ましい。発泡材料における難燃剤の含有量が、上記範囲内であれば、得られる発泡体において、難燃性が良好であるとともに発泡成形性が担保されやすい。難燃剤の含有量は、樹脂等の総量に対して、１～２５質量％の範囲内にあることがより好ましい。 The content of the flame retardant in the foamed material according to the present invention is preferably in the range of 1 to 30% by mass with respect to the total amount of the resin and the like. When the content of the flame retardant in the foam material is within the above range, the resulting foam has good flame retardancy and foam moldability is likely to be ensured. More preferably, the content of the flame retardant is in the range of 1 to 25% by mass with respect to the total amount of the resin and the like.
（その他の添加剤）
　本発明に係る発泡材料は、樹脂等及び本発明の化学発泡剤組成物を必須成分として含有し、さらに任意成分として難燃剤を含有する。本発明に係る発泡材料は、本発明の効果を損なわない範囲で、難燃剤以外のその他の添加剤を含有することができる。その他の添加剤としては、発泡体に一般的に添加される公知の添加剤が適用できる。その他の添加剤としては、ドリップ防止剤、酸化防止剤、滑剤、ヒンダードアミン化合物、紫外線吸収剤、帯電防止剤、蛍光増白剤、顔料、染料等が挙げられる。 (Other additives)
The foaming material according to the present invention contains a resin or the like and the chemical foaming agent composition of the present invention as essential components, and further contains a flame retardant as an optional component. The foam material according to the present invention may contain additives other than the flame retardant as long as the effects of the present invention are not impaired. As other additives, known additives generally added to foams can be applied. Other additives include anti-drip agents, antioxidants, lubricants, hindered amine compounds, ultraviolet absorbers, antistatic agents, fluorescent whitening agents, pigments, dyes, and the like.
＜ドリップ防止剤＞
　ドリップ防止剤は、燃焼時に樹脂材料の滴下（ドリップ）を防止し、難燃性を向上させる目的で添加されるものであり、ドリップ防止剤としては、フッ素系ドリップ防止剤やシリコンゴム類、層状ケイ酸塩等が挙げられる。ドリップ防止剤は１種単独で用いても２種以上併用してもよい。 <Drip prevention agent>
Anti-drip agents are added for the purpose of preventing dripping of resin materials during combustion and improving flame retardancy. silicates and the like. An anti-drip agent may be used individually by 1 type, or may be used in combination of 2 or more types.
＜酸化防止剤＞
　酸化防止剤としては、ヒンダードフェノール類酸化防止剤、亜リン酸エステル類酸化防止剤又はその両方の混合系が挙げられる。 <Antioxidant>
Antioxidants include hindered phenol antioxidants, phosphite ester antioxidants, or a mixture of both.
＜滑剤＞
　滑剤としては、脂肪酸塩、脂肪酸アミド、シランポリマー、固体パラフィン、液体パラフィン、ステアリン酸カルシウム、ステアリン酸亜鉛、ステアリン酸アミド、シリコーン粉末、メチレンビスステアリン酸アミド及びＮ，Ｎ´－エチレンビスステアリン酸アミドからなる群より選ばれる１種又は２種以上のものが挙げられる。 <Lubricant>
Lubricants include fatty acid salts, fatty acid amides, silane polymers, solid paraffin, liquid paraffin, calcium stearate, zinc stearate, stearamide, silicone powder, methylene bis stearamide and N,N'-ethylene bis stearamide. One or two or more selected from the group consisting of:
　本発明に係る発泡材料におけるその他の添加剤の含有量は、本発明の効果を損なわない範囲であり、例えば、発泡材料の全量に対して、合計で０．１～５８質量％程度の範囲内であり、合計で０．１～２２．５質量％の範囲内が好ましい。 The content of other additives in the foamed material according to the present invention is within a range that does not impair the effects of the present invention. and the total content is preferably in the range of 0.1 to 22.5% by mass.
　本発明に係る発泡材料は、上記含有成分を適宜混合して得られる。具体的には、樹脂等及び本発明の化学発泡剤組成物、任意に含有される難燃剤、並びに必要に応じて含有されていてもよいその他の添加剤を、ドライブレンドして得られた混合物を発泡材料とする方法が挙げられる。 The foamed material according to the present invention is obtained by appropriately mixing the above-mentioned components. Specifically, a mixture obtained by dry blending a resin or the like, the chemical foaming agent composition of the present invention, an optionally contained flame retardant, and other additives that may be contained as necessary. is used as a foam material.
　なお、発泡材料の調製においては、本発明の化学発泡剤組成物の代わりに本発明の化学発泡剤マスターバッチを用いてもよい。すなわち、樹脂等及び本発明の化学発泡剤マスターバッチ、任意に含有される難燃剤、並びに必要に応じて含有されていてもよいその他の添加剤を、ドライブレンドして得られた混合物を発泡材料としてもよい。発泡材料の調製に化学発泡剤マスターバッチを用いる場合、発泡材料における樹脂等の含有量は、化学発泡剤マスターバッチにおける樹脂等の量と、それとは別に添加される樹脂等の量の合計量である。 In the preparation of the foaming material, the chemical foaming agent masterbatch of the present invention may be used instead of the chemical foaming agent composition of the present invention. That is, a mixture obtained by dry blending a resin or the like, the chemical foaming agent masterbatch of the present invention, an optionally contained flame retardant, and other additives that may be contained as necessary is used as a foaming material. may be When a chemical foaming agent masterbatch is used to prepare a foaming material, the content of the resin, etc. in the foaming material is the sum of the amount of the resin, etc. in the chemical foaming agent masterbatch and the amount of the resin, etc. added separately. be.
　また、上記で得られた混合物を溶融混練する方法により発泡材料とする方法をとってもよい。溶融混錬の際は、炭酸水素ナトリウムの分解、炭酸水素ナトリウムと酸性物質Ａの反応を極力抑える、すなわち発泡を抑えるために次の操作を行ってもよい。例えば、溶融混練物に圧力をかける、溶融混練物の温度を低く設定する、溶融混錬後直ちに冷却する等の操作である。 Alternatively, a foaming material may be formed by melt-kneading the mixture obtained above. During the melt-kneading, the following operations may be performed to suppress the decomposition of sodium hydrogencarbonate and the reaction between sodium hydrogencarbonate and the acidic substance A as much as possible, that is, to suppress foaming. For example, the operations include applying pressure to the melt-kneaded material, setting the temperature of the melt-kneaded material to a low temperature, and cooling the melt-kneaded material immediately after melt-kneading.
　なお、本発明に係る発泡材料は、上記調製方法に応じて、例えば、粉末状、顆粒状、タブレット（錠剤）状、ペレット状、フレーク状、繊維状、及び液状等の各種形態をとることができる。 The foaming material according to the present invention can take various forms such as powder, granules, tablets, pellets, flakes, fibers, and liquid, depending on the preparation method described above. can.
〔発泡体〕
　本発明の発泡体は、上記発泡材料を発泡成形して得られるものである。発泡成形の方法としては、特に限定されず、炭酸水素ナトリウムを化学発泡剤として用いた公知の発泡体の成形方法が適用できる。具体的には、上記発泡材料を成形し、炭酸水素ナトリウムの分解温度以上に加熱することで、発泡体が得られる。なお、本発明の発泡体を得るための好ましい発泡成形方法は、後述する本発明の製造方法である。 [Foam]
The foam of the present invention is obtained by foam-molding the above foam material. The foam molding method is not particularly limited, and a known foam molding method using sodium hydrogen carbonate as a chemical foaming agent can be applied. Specifically, a foam is obtained by molding the above-mentioned foam material and heating it to the decomposition temperature of sodium hydrogen carbonate or higher. A preferable foam-molding method for obtaining the foam of the present invention is the production method of the present invention, which will be described later.
　本発明の発泡体は、当該発泡体が有する気泡径が微細であり、かつ難燃性の低下が抑制された発泡体である。 The foam of the present invention is a foam in which the cell diameter of the foam is fine and the decrease in flame retardancy is suppressed.
　本発明の発泡体における気泡径は、例えば、以下の方法で測定される平均気泡径として、０．４ｍｍ以下が好ましく、０．２ｍｍ以下がより好ましい。 The cell diameter of the foam of the present invention is preferably 0.4 mm or less, more preferably 0.2 mm or less, as an average cell diameter measured by the following method.
＜気泡径の測定方法＞
　発泡体をカッター等で切断しその断面を、透過型電子顕微鏡、例えば、ＪＥＭ－２０００ＦＸ（日本電子（株）製）により観察し、発泡部の画像を撮影する。ここで、発泡部とは、例えば、金型内で発泡体が成形された場合に、発泡体が有する略気泡が存在しない緻密なスキン層及び均一な気泡を有する発泡部と明らかに気泡の形態が異なるスキン層近傍部を除いた、断面の中心部に近い均一な気泡が観察できる領域をいう。 <Method for measuring bubble diameter>
The foam is cut with a cutter or the like, and the cross section is observed with a transmission electron microscope such as JEM-2000FX (manufactured by JEOL Ltd.) to take an image of the foamed portion. Here, the foamed part means, for example, when the foam is molded in a mold, the foamed part has a dense skin layer in which the foam has almost no cells, and the foamed part has uniform cells. The region where uniform bubbles can be observed near the center of the cross section, excluding the skin layer vicinity where the
　上記発泡部の断面において、ランダムに選択された２ｍｍ×８ｍｍの測定領域について、存在する全ての気泡における最大径を、画像測定機（ＮＥＸＩＶ　ＶＭＲ３０２０）を用いてそれぞれ測定し、平均して平均気泡径とする。 In the cross section of the foamed portion, the maximum diameter of all existing bubbles was measured for a randomly selected measurement area of 2 mm × 8 mm using an image measuring machine (NEXIV VMR3020), and the average bubble diameter was averaged. and
　また、本発明の発泡体における難燃性については、例えば、以下の燃焼試験で測定される燃焼時間を指標として評価することができる。具体的には、上記発泡材料において、本発明の化学発泡剤組成物を含有しない成形材料を成形した成形体を以下の燃焼試験に供した場合の燃焼時間をＴ１とし、本発明の発泡体を以下の燃焼試験に供した場合の燃焼時間をＴ２とした場合に、Ｔ１に比べてＴ２が大きく増加しないことが好ましい。 In addition, the flame retardancy of the foam of the present invention can be evaluated using, for example, the burning time measured in the following burning test as an index. Specifically, in the above-mentioned foam material, a molded article obtained by molding a molding material that does not contain the chemical foaming agent composition of the present invention is subjected to the following combustion test with a combustion time T1, and the foam of the present invention is obtained. Assuming that the combustion time is T2 in the following combustion test, it is preferable that T2 does not greatly increase compared to T1.
　上記Ｔ２とＴ１の関係としては、例えば、Ｔ２／Ｔ１が２．０以下であることが好ましく、１．５以下であることがより好ましい。また、Ｔ２は、具体的には、ＡＳＴＭ　Ｄ３８０１の基準を勘案すれば、３０秒以下が好ましく、１０秒以下がより好ましい。 As for the relationship between T2 and T1, for example, T2/T1 is preferably 2.0 or less, more preferably 1.5 or less. Also, specifically, T2 is preferably 30 seconds or less, more preferably 10 seconds or less, in consideration of the ASTM D3801 standard.
＜燃焼時間＞
　ＡＳＴＭ　Ｄ３８０１に準拠した２０ｍｍ垂直燃焼試験による燃焼時間を測定する。試験片として、１２５±５ｍｍ×１３±０．５ｍｍのサイズで、厚さ２ｍｍの試験片を３本準備する。各試験片をクランプに垂直に取付け、試験片の下端にバーナーを用いて２０ｍｍ炎による１０秒間接炎を２回行い、その燃焼挙動により判定を行う。 <Burning time>
The burning time is measured by a 20 mm vertical burning test according to ASTM D3801. As test pieces, three test pieces having a size of 125±5 mm×13±0.5 mm and a thickness of 2 mm are prepared. Each test piece is vertically attached to a clamp, and a burner is used at the lower end of the test piece to apply two 10-second indirect flames with a 20 mm flame, and the combustion behavior is judged.
　燃焼時間は次の方法で求めた。すなわち、各試験片において２回の接炎における有炎燃焼時間の長い方の時間を燃焼時間として採用する。３本の試験片における当該燃焼時間の平均を燃焼時間とした。 The burning time was obtained by the following method. That is, for each test piece, the longer of the flaming combustion times in two flame contact times is adopted as the combustion time. The average of the burning times for the three test pieces was taken as the burning time.
（用途）
　本発明の発泡体の用途としては、特に限定されず、例えば、家電製品及び自動車等の分野における電気電子部品、電装部品、外装部品、及び内装部品等、並びに各種包装資材、家庭用品、事務用品、配管、及び農業用資材等を挙げることができる。 (Application)
The use of the foam of the present invention is not particularly limited, and examples include electric and electronic parts, electrical components, exterior parts, and interior parts in the fields of home appliances and automobiles, as well as various packaging materials, household goods, and office supplies. , piping, and agricultural materials.
［発泡体の製造方法］
　本発明の発泡体の製造方法は、以下の（１）発泡材料調製工程及び（２）発泡成形工程を有することを特徴とする。 [Method for producing foam]
The method for producing a foam of the present invention is characterized by having the following (1) foam material preparation step and (2) foam molding step.
（１）本発明の化学発泡剤組成物又は本発明の化学発泡剤マスターバッチと、熱可塑性樹脂又は熱可塑性エラストマー（樹脂等）とを混合して発泡材料を得る工程（発泡材料調製工程）
（２）上記（１）で得られた発泡材料を射出成形機にて発泡成形する工程（発泡成形工程） (1) A step of mixing the chemical blowing agent composition of the present invention or the chemical blowing agent masterbatch of the present invention with a thermoplastic resin or thermoplastic elastomer (resin or the like) to obtain a foaming material (foaming material preparation step)
(2) A step of foam-molding the foamed material obtained in (1) above with an injection molding machine (foam molding step)
　本発明の製造方法においては、必要に応じて、（１）発泡材料調製工程及び（２）発泡成形工程以外の工程を有してもよい。以下、各工程を説明する。 The production method of the present invention may have steps other than (1) foam material preparation step and (2) foam molding step, if necessary. Each step will be described below.
〔発泡材料調製工程〕
　本発明の製造方法における発泡材料調製工程は、上記発泡体において説明した発泡材料の調製方法と同様の方法で行うことができる。発泡材料における、各含有成分の含有量についても、上記発泡体において説明した発泡材料の各含有成分の含有量と同様の量とすることができる。 [Foam material preparation step]
The foaming material preparation step in the production method of the present invention can be carried out in the same manner as the foaming material preparation method described in the above foam. The content of each component in the foam material can also be set to the same amount as the content of each component in the foam material described above for the foam.
　具体的には、樹脂等及び本発明の化学発泡剤組成物、任意に含有される難燃剤、並びに必要に応じて含有されていてもよいその他の添加剤を、ドライブレンドして得られた混合物を発泡材料とする方法が挙げられる。あるいは、上記において、本発明の化学発泡剤組成物の代わりに本発明の化学発泡剤マスターバッチを用いて発泡材料を調製してもよい。発泡材料の調製に化学発泡剤マスターバッチを用いる場合、発泡材料における樹脂等の含有量は、化学発泡剤マスターバッチにおける樹脂等の量と、それとは別に添加される樹脂等の量の合計量である。 Specifically, a mixture obtained by dry blending a resin or the like, the chemical foaming agent composition of the present invention, an optionally contained flame retardant, and other additives that may be contained as necessary. is used as a foam material. Alternatively, in the above, the foaming material may be prepared using the chemical blowing agent masterbatch of the present invention instead of the chemical blowing agent composition of the present invention. When a chemical foaming agent masterbatch is used to prepare a foaming material, the content of the resin, etc. in the foaming material is the sum of the amount of the resin, etc. in the chemical foaming agent masterbatch and the amount of the resin, etc. added separately. be.
　また、溶融混練により発泡材料を調製してもよい。溶融混錬の際は、炭酸水素ナトリウムの分解、炭酸水素ナトリウムと酸性物質Ａの反応を極力抑える、すなわち発泡を抑えるために次の操作を行ってもよい。例えば、溶融混練物に圧力をかける、溶融混練物の温度を低く設定する、溶融混錬後直ちに冷却する等の操作である。 Alternatively, the foaming material may be prepared by melt-kneading. During the melt-kneading, the following operations may be performed to suppress the decomposition of sodium hydrogencarbonate and the reaction between sodium hydrogencarbonate and the acidic substance A as much as possible, that is, to suppress foaming. For example, the operations include applying pressure to the melt-kneaded material, setting the temperature of the melt-kneaded material to a low temperature, and cooling the melt-kneaded material immediately after melt-kneading.
　ドライブレンドの方法としては、発泡材料が含有する各成分を、例えば、タンブラーやヘンシェルミキサーとして知られた高速ミキサー等の各種混合機を用いて行う方法が挙げられる。 As a method of dry blending, there is a method of mixing each component contained in the foaming material using various mixers such as a tumbler and a high-speed mixer known as a Henschel mixer.
　溶融混練は、一般的には、バンバリーミキサー、ロール、プラストグラフ、押出機（単軸押出機、多軸押出機（例えば、二軸押出機）等）、及びニーダー等の混練装置を用いて行われる。これらの中でも、溶融混練は、生産効率がよいことから、押出機を用いて行うことが好ましい。さらに、高いせん断性を付与できることから、溶融混練は多軸押出機を用いることが好ましく、二軸押出機を用いることがより好ましい。ここで、押出機の用語は、押出混練機を含む範疇で用いられる。 Melt-kneading is generally performed using a kneading device such as a Banbury mixer, roll, plastograph, extruder (single-screw extruder, multi-screw extruder (e.g., twin-screw extruder), etc.), and kneader. will be Among these, melt-kneading is preferably carried out using an extruder because of its high production efficiency. Furthermore, a multi-screw extruder is preferably used for melt-kneading, and a twin-screw extruder is more preferably used, since high shearability can be imparted. Here, the term extruder is used in a category including an extrusion kneader.
　溶融混練の際の温度及び圧力は、炭酸水素ナトリウムの分解、炭酸水素ナトリウムと酸性物質Ａの反応を極力抑える温度及び圧力とする。溶融混練に押出機を用いる場合、混練溶融温度はシリンダ温度に相当する。 The temperature and pressure during melt-kneading should be such that the decomposition of sodium hydrogen carbonate and the reaction between sodium hydrogen carbonate and acidic substance A are suppressed as much as possible. When an extruder is used for melt-kneading, the kneading melt temperature corresponds to the cylinder temperature.
　溶融混練に押出機を用いる場合、スクリュー回転数は、５０～３００ｒｐｍの範囲が好ましい。また、押出機からの発泡材料の吐出量は、１～５０ｋｇ／ｈｒの範囲が好ましい。 When using an extruder for melt-kneading, the screw rotation speed is preferably in the range of 50 to 300 rpm. Further, the discharge rate of the foamed material from the extruder is preferably in the range of 1 to 50 kg/hr.
　発泡材料調製工程においては、混練物をストランド状に押し出した後、当該ストランド状の混練物をペレット状やフレーク状等の形態に加工することができる。 In the foaming material preparation step, after the kneaded material is extruded into a strand, the strand-shaped kneaded material can be processed into pellets, flakes, or the like.
〔発泡成形工程〕
　本発明の製造方法における発泡成形工程は、上記で得られた発泡材料を、射出成形機を用いて発泡成形する工程である。 [Foam molding process]
The foam molding step in the production method of the present invention is a step of foam molding the foamed material obtained above using an injection molding machine.
　射出成形機としては、例えば、発泡材料を加熱するシリンダと、シリンダに連通しシリンダから加熱された発泡材料を射出する射出部と、射出された発泡材料を所定の形状に成形するための金型を備える、一般的な射出成形機を用いることができる。 The injection molding machine includes, for example, a cylinder that heats the foam material, an injection part that communicates with the cylinder and injects the heated foam material from the cylinder, and a mold for molding the injected foam material into a predetermined shape. A general injection molding machine can be used.
　シリンダ内での発泡材料の加熱は、発泡材料が射出部から射出可能な状態（粘度）となる温度とされる。当該加熱温度は、例えば、発泡材料が含有する樹脂等の溶融温度以上の温度である。樹脂等としてポリプロピレン系樹脂を用いる場合、発泡材料の加熱温度は、１９０～２２０℃の範囲が好ましく、２００～２１０℃がより好ましい。樹脂等としてＡＢＳ樹脂を用いる場合、発泡材料の加熱温度は２２０～２４０℃の範囲が好ましい。なお、シリンダ内の発泡材料の温度は、シリンダの温度と略同じとして扱うことができる。発泡材料が充填されたシリンダ内で発泡材料の温度が炭酸水素ナトリウムの分解温度以上となっても、密閉状態下、発泡材料は体積を増加させることができないため発泡は起こらない。 The heating of the foaming material in the cylinder is the temperature at which the foaming material can be injected from the injection part (viscosity). The heating temperature is, for example, a temperature equal to or higher than the melting temperature of resin or the like contained in the foam material. When a polypropylene-based resin is used as the resin or the like, the heating temperature of the foam material is preferably in the range of 190 to 220°C, more preferably 200 to 210°C. When ABS resin is used as the resin or the like, the heating temperature of the foam material is preferably in the range of 220-240.degree. It should be noted that the temperature of the foaming material inside the cylinder can be treated as substantially the same as the temperature of the cylinder. Even if the temperature of the foaming material rises above the decomposition temperature of sodium bicarbonate in the cylinder filled with the foaming material, foaming does not occur because the foaming material cannot increase its volume under the sealed condition.
　射出条件は、射出成形機の構造、特には、射出部の構造に応じて適宜調整される。射出圧力は、加熱された発泡材料をシリンダから金型のキャビティ内に向かって射出できる圧力であり、概ね１０～２００ＭＰａの範囲とすることができる。射出時間、すなわち、射出開始から射出終了までの時間は、例えば、２秒以内が好ましい。射出速度は、例えば、用いる樹脂等の種類、製品形状、製品厚み等によりにより適宜調整される。 The injection conditions are adjusted as appropriate according to the structure of the injection molding machine, especially the structure of the injection section. The injection pressure is the pressure at which the heated foaming material can be injected from the cylinder into the cavity of the mold, and can be in the range of approximately 10 to 200 MPa. The injection time, that is, the time from the start of injection to the end of injection, is preferably within 2 seconds, for example. The injection speed is appropriately adjusted according to, for example, the type of resin used, the shape of the product, the thickness of the product, and the like.
　射出時において、上記上限値を超えた射出時間となると、樹脂等の結晶化が起こり、発泡倍率を高めることが難しくなったり、マトリックス中の発泡ガスが表面へと逃げることを許すこととなり、成形された発泡体表面にシルバーマーク等が発生しやすくなるおそれがある。 At the time of injection, if the injection time exceeds the above upper limit, crystallization of the resin, etc. will occur, making it difficult to increase the expansion ratio, or allowing the foaming gas in the matrix to escape to the surface, resulting in molding. There is a risk that silver marks or the like are likely to occur on the surface of the foam that has been treated.
　金型のキャビティ内に射出された発泡材料は、キャビティの形状に発泡成形される。用いられる金型のキャビティの容積は、原料の発泡材料の容積より大きく設定され、射出により注入された発泡材料が金型のキャビティ内で発泡することによりキャビティ内の全体が発泡体で充填される。金型のキャビティの容積を、用いた発泡材料の容積で除した値が発泡倍率に相当する。 The foam material injected into the mold cavity is foam-molded into the shape of the cavity. The volume of the cavity of the mold used is set larger than the volume of the raw foaming material, and the foaming material injected by injection expands in the cavity of the mold, thereby filling the entire cavity with foam. . A value obtained by dividing the volume of the mold cavity by the volume of the foaming material used corresponds to the expansion ratio.
　発泡成形時の発泡材料の温度は、炭酸水素ナトリウムの分解温度以上の温度であり、好ましくは、１７０～２３０℃の範囲である。なお、発泡成形時の発泡材料の温度は、例えば、射出時の発泡材料の温度、すなわち、シリンダの温度と見積もってもよい。 The temperature of the foam material during foam molding is a temperature equal to or higher than the decomposition temperature of sodium hydrogencarbonate, preferably in the range of 170 to 230°C. The temperature of the foam material during foam molding may be estimated, for example, as the temperature of the foam material during injection, that is, the temperature of the cylinder.
　金型はキャビティの容積が固定された金型であってもよく、キャビティの容積が可変である金型を用いてもよい。キャビティの容積が可変である金型を用いる場合、発泡材料を充填するときには容積を小さくしておき、充填後にキャビティの容積を拡大することで積極的に気泡発生、拡大を促進させることができる。このような、成形法をコアバック成形という。コアバック成形によれば、発泡材料が金型に接触するときにスキン層が形成されるため、表面外観が良好な発泡体が得られる。 The mold may be a mold with a fixed cavity volume, or a mold with a variable cavity volume. When using a mold with a variable cavity volume, the volume is kept small when the foam material is filled, and by expanding the cavity volume after filling, the generation and expansion of air bubbles can be actively promoted. Such a molding method is called core-back molding. According to core-back molding, a skin layer is formed when the foam material contacts the mold, so a foam with a good surface appearance can be obtained.
　コアバック成形の条件としては、均一な発泡を行う観点から、キャビティへの発泡材料の充填終了から、キャビティの容積拡大を開始するまでの時間を短く、例えば、２秒以内とすることが好ましい。 As for the conditions for core-back molding, from the viewpoint of performing uniform foaming, it is preferable to shorten the time from the end of filling the cavity with the foaming material to the start of expanding the volume of the cavity, for example, within 2 seconds.
　また、発泡成形後に金型を冷却することで、得られた発泡体を冷却することが好ましい。なお、射出時間が短い場合には、金型の温度は、発泡材料の射出時から冷却温度に設定しておくことも可能である。冷却温度（金型及び発泡体の温度）は、例えば、４０～８０℃が好ましい。冷却時間は、例えば、用いる樹脂等の種類、製品形状、製品厚み等によりにより適宜調整される。冷却後、金型から発泡体を取り出すことで、発泡体の製造が完了する。 In addition, it is preferable to cool the resulting foam by cooling the mold after foam molding. If the injection time is short, the temperature of the mold can be set to the cooling temperature from the time of injection of the foam material. The cooling temperature (the temperature of the mold and foam) is preferably 40 to 80°C, for example. The cooling time is appropriately adjusted according to, for example, the type of resin used, the shape of the product, the thickness of the product, and the like. After cooling, the foam production is completed by removing the foam from the mold.
　以下、実施例を挙げて本発明を具体的に説明するが、本発明はこれらに限定されるものではない。なお、実施例において「部」あるいは「％」の表示を用いるが、特に断りがない限り「質量部」あるいは「質量％」を表す。 The present invention will be specifically described below with reference to examples, but the present invention is not limited to these. In addition, although "parts" or "%" is used in the examples, "mass parts" or "mass%" is indicated unless otherwise specified.
［化学発泡剤組成物の調製］
　炭酸水素ナトリウムの０．２質量部に対して表Ｉに示す化合物をそれぞれ１質量部ずつ混合して、本発明の化学発泡剤組成物１０～１３及び比較例の化学発泡剤組成物１～９、化学発泡剤組成物１４～１５を調製した。表Ｉには、化合物の融点、当該化合物を水溶液とした際のｐＨ及び化合物が有機化合物であるか無機化合物であるかを示した。また、表Ｉには、化学発泡剤組成物中の融点４００℃未満の有機化合物の含有量を含有量Ｂ［質量％］として併せて示した。 [Preparation of chemical blowing agent composition]
Chemical Blowing Agent Compositions 10 to 13 of the present invention and Chemical Blowing Agent Compositions 1 to 9 of Comparative Examples were prepared by mixing 1 part by mass of each of the compounds shown in Table I with 0.2 part by mass of sodium hydrogen carbonate. , Chemical Blowing Agent Compositions 14-15 were prepared. Table I shows the melting point of the compound, the pH when the compound is made into an aqueous solution, and whether the compound is an organic compound or an inorganic compound. Table I also shows the content of the organic compound having a melting point of less than 400°C in the chemical foaming agent composition as a content B [% by mass].
＜評価＞
　樹脂等としてポリプロピレン（ノバテックＰＰ＿ＭＧ０３ＢＤ（製品名、日本ポリプロ社製）を１００質量部、難燃剤としてビス［３，５－ジブロモ－４－（２，３－ジブロモプロポキシ）フェニル］スルホンを５質量部、及び上記化学発泡剤組成物１を１．２質量部、秤量して手動で混合して発泡材料１を調製した。同様にして、化学発泡剤組成物１の代わりに化学発泡剤組成物２～１５を含有する発泡材料２～１５を調製した。 <Evaluation>
100 parts by mass of polypropylene (Novatec PP_MG03BD (product name, manufactured by Japan Polypro Co., Ltd.) as a resin etc., 5 parts by mass of bis[3,5-dibromo-4-(2,3-dibromopropoxy)phenyl]sulfone as a flame retardant, and 1.2 parts by mass of the above chemical foaming agent composition 1 were weighed and mixed manually to prepare foaming material 1. Similarly, instead of chemical foaming agent composition 1, chemical foaming agent compositions 2 to Foamed materials 2-15 containing 15 were prepared.
　発泡材料１～１５について、射出成形機（ＲＯＢＯＳＨＯＴ　２０００ｉ　５０Ｂ、ＦＡＮＵＣ社製）を用いて、以下の射出成形条件１で発泡倍率１．１倍の発泡体（発泡体のサイズは、燃焼時間測定用の試験片と同じサイズである）を成形した。シリンダ温度は、シリンダ内及び射出時の発泡材料温度に相当する。なお、金型は容積が固定された金型を用いた。また、発泡体成形中、金型には圧力を印加しなかった。金型の温度は、冷却温度に相当する。 For foam materials 1 to 15, using an injection molding machine (ROBOSHOT 2000i 50B, manufactured by FANUC), a foam with an expansion ratio of 1.1 under the following injection molding condition 1 (the size of the foam is for measuring the burning time (which is the same size as the test piece of ) was molded. The cylinder temperature corresponds to the foam temperature in the cylinder and during injection. A mold having a fixed volume was used. Also, no pressure was applied to the mold during foam molding. The mold temperature corresponds to the cooling temperature.
（射出成形条件１）
　シリンダ温度（発泡材料温度）；２００℃
　射出圧；２０ＭＰａ
　射出時間（射出開始から射出終了までの時間）；０．９秒
　射出速度；４０［ｍｍ／ｓ］
　金型温度；５０℃
　冷却時間；１５秒 (Injection molding condition 1)
Cylinder temperature (foaming material temperature); 200°C
Injection pressure; 20MPa
Injection time (time from injection start to injection end); 0.9 seconds Injection speed; 40 [mm/s]
Mold temperature; 50°C
Cooling time; 15 seconds
　得られた発泡体について、上記の方法で、気泡径及び燃焼時間（Ｔ２）を測定した。また、発泡材料１において、化学発泡剤組成物１を含有しない樹脂組成物を調製し、射出成形を行って得られた成形体について、燃焼時間（Ｔ１）を測定したところ、４．９［ｓｅｃ］であった。表Ｉに気泡径及び燃焼時間（Ｔ２）と共に、Ｔ２／Ｔ１及びＴ２－Ｔ１を示す。 For the resulting foam, the cell diameter and burning time (T2) were measured by the methods described above. In addition, in the foaming material 1, a resin composition that does not contain the chemical foaming agent composition 1 was prepared, and the molded body obtained by injection molding was measured for the combustion time (T1), which was 4.9 [sec. ]Met. Table I shows T2/T1 and T2-T1 along with bubble diameter and burning time (T2).
　また、図１に炭酸水素ナトリウムと併用した化合物のｐＨ（測定温度２３℃）と得られる発泡体の気泡径との関係を表すグラフを示す。 In addition, FIG. 1 shows a graph showing the relationship between the pH of the compound used in combination with sodium hydrogen carbonate (measurement temperature 23° C.) and the cell diameter of the resulting foam.
Figure JPOXMLDOC01-appb-T000001
Figure JPOXMLDOC01-appb-T000001
　表Ｉ及び図１から、炭酸水素ナトリウムと共にｐＨが７未満（条件１）の酸性物質を用いた場合、得られる発泡体における気泡径を微細なものにできることがわかる。また、炭酸水素ナトリウムと共に用いる化合物が無機化合物の場合及び融点が４００℃以上の有機化合物の場合（条件２）、難燃性の低下を抑制していることがわかる。上記条件１及び条件２を満足する化合物を酸性物質Ａとして炭酸水素ナトリウムと共に含有する化学発泡剤組成物１０～１３は、気泡の微細化と難燃性低下の抑制を両立するという、本発明の効果を達成していることがわかる。 From Table I and FIG. 1, it can be seen that when an acidic substance having a pH of less than 7 (Condition 1) is used together with sodium bicarbonate, the resulting foam can have fine cell diameters. Moreover, when the compound used with sodium hydrogencarbonate is an inorganic compound and when the compound is an organic compound having a melting point of 400° C. or higher (Condition 2), it can be seen that deterioration in flame retardancy is suppressed. The chemical blowing agent compositions 10 to 13 containing a compound that satisfies the conditions 1 and 2 as the acidic substance A together with sodium bicarbonate achieve both miniaturization of cells and suppression of deterioration in flame retardancy. It turns out that the effect is achieved.
［発泡体の製造］
（１）発泡材料の調製
　上記で得られた化学発泡剤組成物１０～１３と以下の熱可塑性樹脂及び難燃剤を用いて、表IIに示す発泡材料２１～２９を調製した。また、比較例として、化学発泡剤組成物１０～１３の代わりに炭酸水素ナトリウムのみを用いた発泡材料３０～３２、化学発泡剤組成物１０～１３の代わりに、炭酸水素ナトリウムとクエン酸一ナトリウム（酸性物質Ａの範囲外）からなる化学発泡剤組成物３を用いた発泡材料３３～３５（表IIに組成に示す。）を調製した。 [Production of foam]
(1) Preparation of foaming materials Foaming materials 21 to 29 shown in Table II were prepared using the chemical foaming agent compositions 10 to 13 obtained above and the following thermoplastic resins and flame retardants. In addition, as comparative examples, foaming materials 30 to 32 using only sodium hydrogen carbonate instead of the chemical blowing agent compositions 10 to 13, sodium hydrogen carbonate and monosodium citrate instead of the chemical blowing agent compositions 10 to 13 Foam materials 33-35 (composition shown in Table II) were prepared using chemical blowing agent composition 3 consisting of (outside the range of acidic substance A).
（熱可塑性樹脂）
　ポリプロピレン；ノバテックＰＰ＿ＭＧ０３ＢＤ（製品名、日本ポリプロ社製、以下、「ＰＰ」と記す。
　ＡＢＳ樹脂；セビアンＶ＿６６０ＳＦ（製品名、ダイセルポリマー社製、以下、「ＡＢＳ」と記す。
　ポリアミド樹脂；アミラン＿ＣＭ１０１７（製品名、東レ社製、以下、「ＰＡ」と記す。 (Thermoplastic resin)
Polypropylene; Novatec PP_MG03BD (product name, manufactured by Japan Polypropylene Corporation, hereinafter referred to as "PP".
ABS resin: Cebian V_660SF (product name, manufactured by Daicel Polymer Ltd., hereinafter referred to as "ABS").
Polyamide resin; Amilan_CM1017 (product name, manufactured by Toray Industries, Inc., hereinafter referred to as "PA".
（難燃剤）
　ビス［３，５－ジブロモ－４－（２，３－ジブロモプロポキシ）フェニル］スルホン（以下、「難燃剤１」と記す。）
　ビス（ペンタブロモフェニル）エタン（以下、「難燃剤２」と記す。）
　縮合リン酸エステル（ＰＸ－２００（製品名、大八化学工業社製、以下、「難燃剤３」と記す。） (Flame retardants)
Bis[3,5-dibromo-4-(2,3-dibromopropoxy)phenyl]sulfone (hereinafter referred to as “flame retardant 1”)
Bis(pentabromophenyl)ethane (hereinafter referred to as "flame retardant 2")
Condensed phosphate ester (PX-200 (product name, manufactured by Daihachi Chemical Industry Co., Ltd., hereinafter referred to as “flame retardant 3”)
Figure JPOXMLDOC01-appb-T000002
Figure JPOXMLDOC01-appb-T000002
（２）発泡体の製造
　上記で得られた発泡材料２１～３５を用いて、射出成形機（ＲＯＢＯＳＨＯＴ＿２０００ｉ＿５０Ｂ（製品名、ＦＡＮＵＣ社製）により、熱可塑性樹脂としてＰＰを用いた場合は上記射出成形条件１で、ＡＢＳを用いた場合は以下の射出成形条件２で、ＰＡを用いた場合は以下の射出成形条件３で、発泡倍率１．１倍の発泡体２１～３５（発泡体のサイズは、燃焼時間測定用の試験片と同じサイズである）を成形した。シリンダ温度は、シリンダ内及び射出時の発泡材料温度に相当する。なお、金型は容積が固定された金型を用いた。また、発泡体成形中、金型には圧力を印加しなかった。金型の温度は、冷却温度に相当する。 (2) Production of foams Using the foam materials 21 to 35 obtained above, an injection molding machine (ROBOSHOT_2000i_50B (product name, manufactured by FANUC) is used. When PP is used as the thermoplastic resin, the above injection molding conditions 1, the following injection molding conditions 2 when ABS is used, and the following injection molding conditions 3 when PA is used, foams 21 to 35 with an expansion ratio of 1.1 (the size of the foam is The same size as the test piece for measuring the burning time) was molded.The cylinder temperature corresponds to the temperature of the foam material in the cylinder and during injection.The mold used was a mold with a fixed volume. Also, no pressure was applied to the mold during foam molding, and the temperature of the mold corresponds to the cooling temperature.
（射出成形条件２）
　シリンダ温度（発泡材料温度）；２２０℃
　射出圧；２０ＭＰａ
　射出時間（射出開始から射出終了までの時間）；０．９秒
　射出速度；４０［ｍｍ／ｓ］
　金型温度；５０℃
　冷却時間；１５秒 (Injection molding condition 2)
Cylinder temperature (foaming material temperature); 220°C
Injection pressure; 20MPa
Injection time (time from injection start to injection end); 0.9 seconds Injection speed; 40 [mm/s]
Mold temperature; 50°C
Cooling time; 15 seconds
（射出成形条件３）
　シリンダ温度（発泡材料温度）；２５０℃
　射出圧；２０ＭＰａ
　射出時間（射出開始から射出終了までの時間）；０．９秒
　射出速度；４０［ｍｍ／ｓ］
　金型温度；７０℃
　冷却時間；１５秒 (Injection molding condition 3)
Cylinder temperature (foaming material temperature); 250°C
Injection pressure; 20MPa
Injection time (time from injection start to injection end); 0.9 seconds Injection speed; 40 [mm/s]
Mold temperature; 70°C
Cooling time; 15 seconds
　得られた発泡体について、上記の方法で、気泡径及び燃焼時間（Ｔ２）を測定した。また、各発泡材料において、化学発泡剤組成物又は炭酸水素ナトリウムを含有しない樹脂組成物を調製し、射出成形を行って得られた成形体について、燃焼時間（Ｔ１）を測定した。表IIIに、気泡径及び燃焼時間（Ｔ２）、燃焼時間（Ｔ１）と共に、Ｔ２／Ｔ１及びＴ２－Ｔ１を示す。 For the resulting foam, the cell diameter and burning time (T2) were measured by the methods described above. Also, for each foaming material, a chemical foaming agent composition or a resin composition containing no sodium hydrogencarbonate was prepared, and the combustion time (T1) was measured for the molding obtained by injection molding. Table III shows T2/T1 and T2-T1, along with bubble diameter, combustion time (T2), and combustion time (T1).
Figure JPOXMLDOC01-appb-T000003
Figure JPOXMLDOC01-appb-T000003
　表IIIから、本発明の発泡体は、気泡の微細化と難燃性低下の抑制を両立するという、本発明の効果を達成していることがわかる。 From Table III, it can be seen that the foam of the present invention achieves the effect of the present invention, that is, both miniaturization of cells and suppression of deterioration in flame retardancy.
　本発明によれば、発泡体の成形に用いた際に気泡の微細化と難燃性低下の抑制が両立できる化学発泡剤組成物及び化学発泡剤マスターバッチを提供することができる。また、上記化学発泡剤組成物又は化学発泡剤マスターバッチを用いて製造された気泡の微細化と難燃性低下の抑制が共に達成された発泡体及びその製造方法を提供することができる。 According to the present invention, it is possible to provide a chemical foaming agent composition and a chemical foaming agent masterbatch that can achieve both miniaturization of cells and suppression of deterioration in flame retardancy when used for molding a foam. In addition, it is possible to provide a foam produced using the chemical foaming agent composition or the chemical foaming agent masterbatch, which achieves both miniaturization of cells and suppression of deterioration in flame retardancy, and a method for producing the same.

Claims (10)

  1. 　炭酸水素ナトリウムと酸性物質とを含有する化学発泡剤組成物であって、
    　前記酸性物質が、無機化合物又は融点が４００℃以上の有機化合物である化学発泡剤組成物。     A chemical blowing agent composition containing sodium bicarbonate and an acidic substance,
    The chemical foaming agent composition, wherein the acidic substance is an inorganic compound or an organic compound having a melting point of 400° C. or higher.
  2. 　前記化学発泡剤組成物の全量に対して、融点が４００℃未満の有機化合物を５８質量％以下の範囲内で含有する請求項１に記載の化学発泡剤組成物。 The chemical blowing agent composition according to claim 1, which contains 58% by mass or less of an organic compound having a melting point of less than 400°C with respect to the total amount of the chemical blowing agent composition.
  3. 　前記酸性物質が、ホウ酸、三酸化二ホウ素、リン酸二水素ナトリウム及び亜硫酸水素ナトリウムから選ばれる少なくとも１種を含む請求項１又は請求項２に記載の化学発泡剤組成物。 The chemical blowing agent composition according to claim 1 or claim 2, wherein the acidic substance contains at least one selected from boric acid, diboron trioxide, sodium dihydrogen phosphate and sodium hydrogen sulfite.
  4. 　請求項１から請求項３までのいずれか一項に記載の化学発泡剤組成物と、熱可塑性樹脂又は熱可塑性エラストマーと、を含有する化学発泡剤マスターバッチ。 A chemical blowing agent masterbatch containing the chemical blowing agent composition according to any one of claims 1 to 3 and a thermoplastic resin or thermoplastic elastomer.
  5. 　請求項１から請求項３までのいずれか一項に記載の化学発泡剤組成物又は請求項４に記載の化学発泡剤マスターバッチと、熱可塑性樹脂又は熱可塑性エラストマーと、を含有する発泡材料を発泡成形した発泡体。 A foaming material containing the chemical blowing agent composition according to any one of claims 1 to 3 or the chemical blowing agent masterbatch according to claim 4 and a thermoplastic resin or thermoplastic elastomer A foam molded by foaming.
  6. 　前記発泡体の全量に対する、前記化学発泡剤組成物由来の融点が４００℃未満の有機化合物の含有割合が、１質量％以下の範囲内である請求項５に記載の発泡体。 The foam according to claim 5, wherein the content of the organic compound having a melting point of less than 400°C derived from the chemical foaming agent composition is within a range of 1% by mass or less with respect to the total amount of the foam.
  7. 　前記熱可塑性樹脂又は熱可塑性エラストマーが、ポリオレフィン樹脂、アクリロニトリル－ブタジエン－スチレン樹脂、ポリスチレン樹脂、ポリアミド樹脂、ポリ塩化ビニル樹脂、エチレン酢酸ビニル樹脂及び熱可塑性エラストマーから選ばれる少なくとも１種を含む請求項５又は請求項６に記載の発泡体。 5. Said thermoplastic resin or thermoplastic elastomer comprises at least one selected from polyolefin resin, acrylonitrile-butadiene-styrene resin, polystyrene resin, polyamide resin, polyvinyl chloride resin, ethylene vinyl acetate resin and thermoplastic elastomer. Or the foam of Claim 6.
  8. 　さらに、難燃剤を含有する請求項５から請求項７までのいずれか一項に記載の発泡体。 The foam according to any one of claims 5 to 7, further comprising a flame retardant.
  9. 　請求項１から請求項３までのいずれか一項に記載の化学発泡剤組成物又は請求項４に記載の化学発泡剤マスターバッチと、熱可塑性樹脂又は熱可塑性エラストマーとを混合して発泡材料を得る工程と、
    　前記発泡材料を射出成形機にて発泡成形する工程と、
    　を有する発泡体の製造方法。     The chemical blowing agent composition according to any one of claims 1 to 3 or the chemical blowing agent masterbatch according to claim 4 is mixed with a thermoplastic resin or thermoplastic elastomer to form a foaming material. a process of obtaining
    a step of foam-molding the foam material with an injection molding machine;
    A method for producing a foam having
  10. 　前記発泡材料における前記熱可塑性樹脂又は熱可塑性エラストマーの総量に対する前記化学発泡剤組成物の割合が０．１～１．７質量％の範囲内にある請求項９に記載の発泡体の製造方法。 The method for producing a foam according to claim 9, wherein the ratio of the chemical foaming agent composition to the total amount of the thermoplastic resin or thermoplastic elastomer in the foam material is within the range of 0.1 to 1.7% by mass.
PCT/JP2022/005949 2021-03-19 2022-02-15 Chemical foaming agent composition, chemical foaming agent master batch, foam and method for producing foam WO2022196221A1 (en)

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Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2006131719A (en) * 2004-11-04 2006-05-25 Kaneka Corp Thermoplastic resin foam with improved heat insulation and its manufacturing process
JP2014159541A (en) * 2013-01-22 2014-09-04 Sekisui Chem Co Ltd Thermally expandable fire-resistant resin composition
JP2016505659A (en) * 2012-11-29 2016-02-25 コンパニー ゼネラール デ エタブリッスマン ミシュラン Vehicle tire having a tread containing a heat-foamable rubber composition
CN111205503A (en) * 2020-02-21 2020-05-29 中化石化销售有限公司 Foaming agent material, foaming agent master batch and preparation method thereof

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2006131719A (en) * 2004-11-04 2006-05-25 Kaneka Corp Thermoplastic resin foam with improved heat insulation and its manufacturing process
JP2016505659A (en) * 2012-11-29 2016-02-25 コンパニー ゼネラール デ エタブリッスマン ミシュラン Vehicle tire having a tread containing a heat-foamable rubber composition
JP2014159541A (en) * 2013-01-22 2014-09-04 Sekisui Chem Co Ltd Thermally expandable fire-resistant resin composition
CN111205503A (en) * 2020-02-21 2020-05-29 中化石化销售有限公司 Foaming agent material, foaming agent master batch and preparation method thereof

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