WO2024070750A1 - Method for producing dip-formed object, and dip-formed object - Google Patents

Method for producing dip-formed object, and dip-formed object Download PDF

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Publication number
WO2024070750A1
WO2024070750A1 PCT/JP2023/033643 JP2023033643W WO2024070750A1 WO 2024070750 A1 WO2024070750 A1 WO 2024070750A1 JP 2023033643 W JP2023033643 W JP 2023033643W WO 2024070750 A1 WO2024070750 A1 WO 2024070750A1
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Prior art keywords
mold
rubber latex
latex composition
rubber
water
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PCT/JP2023/033643
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French (fr)
Japanese (ja)
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晃平 澤田
聖司 西岡
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住友精化株式会社
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C41/00—Shaping by coating a mould, core or other substrate, i.e. by depositing material and stripping-off the shaped article; Apparatus therefor
    • B29C41/02—Shaping by coating a mould, core or other substrate, i.e. by depositing material and stripping-off the shaped article; Apparatus therefor for making articles of definite length, i.e. discrete articles
    • B29C41/14—Dipping a core
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C41/00—Shaping by coating a mould, core or other substrate, i.e. by depositing material and stripping-off the shaped article; Apparatus therefor
    • B29C41/34—Component parts, details or accessories; Auxiliary operations
    • B29C41/36—Feeding the material on to the mould, core or other substrate
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
    • C08L1/00—Compositions of cellulose, modified cellulose or cellulose derivatives
    • C08L1/08—Cellulose derivatives
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
    • C08L21/00—Compositions of unspecified rubbers
    • C08L21/02—Latex
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
    • C08L5/00—Compositions of polysaccharides or of their derivatives not provided for in groups C08L1/00 or C08L3/00

Definitions

  • the present invention relates to a method for producing a dip-molded body, a dip-molded body, etc. More specifically, the present invention relates to a method for producing a dip-molded body by dip molding using rubber latex, and a dip-molded body that can be produced by the method.
  • dip molded articles using rubber latex is widely practiced, and examples of such products include gloves, sacks, catheters, and balloons. These products are manufactured by dipping a mold of the desired shape (also called a molding mold or membrane mold) into rubber latex, adhering rubber particles to the mold until the desired thickness is reached, and then vulcanizing the rubber attached to the mold as necessary.
  • a mold of the desired shape also called a molding mold or membrane mold
  • Patent Document 1 discloses a method for producing a dip-molded body from latex using a coagulating liquid containing calcium chloride.
  • Patent Document 2 discloses a method for producing a dip-molded body from natural rubber latex containing a heat-sensitizing agent and an anodic coagulant.
  • Patent Document 3 discloses a method for producing a dip-molded body from nitrile rubber latex containing a specific polysaccharide, using alcohol as a coagulant.
  • Patent Document 4 discloses a method for producing a dip-molded body by immersing a mold to which calcium ions are attached in chlorosulfonated polyethylene latex containing sodium alginate.
  • the object of the present invention is to provide a method for stably producing a relatively thick molded product by the dip molding method.
  • Another object of the present invention is to provide a relatively thick, practical dip molded product.
  • the present invention provides a method for producing a dip-molded body and a dip-molded body, for example, as described in the following sections.
  • Section A-1 A mold having a surface temperature of 30° C. or more and less than 100° C. is immersed in a rubber latex composition containing a water-soluble polymer having an acidic functional group and a rubber, thereby adhering the rubber latex composition to the surface of the mold; and gelling the water-soluble polymer in the rubber latex composition attached to the mold;
  • a method for producing a dip-molded body comprising the steps of: Section A-2.
  • the rubber latex composition is a latex composition containing a water-soluble polymer having an acidic functional group and a chlorosulfonated polyolefin.
  • Section A-9 Prior to depositing the rubber latex composition on the surface of the mold, The method according to any one of items A-1 to A-8, further comprising attaching a coagulant to the mold. Section A-10. After applying the rubber latex composition to the surface of the mold, The method according to any one of items A-1 to A-9, comprising attaching a coagulant to a mold having the rubber latex composition attached to its surface. Section A-11.
  • a dip-molded article comprising a water-soluble polymer having an acidic functional group and a rubber, the thickness of the membrane being greater than 0.3 mm, and the thickness unevenness calculated as follows being 50% or less.
  • Section B-1 A mold having a surface temperature of 30° C. or more and less than 100° C. is immersed in a rubber latex composition containing a water-soluble polymer having an acidic functional group (excluding sodium alginate) and rubber, thereby adhering the rubber latex composition to the surface of the mold; and gelling the water-soluble polymer in the rubber latex composition attached to the mold;
  • Section B-3 The method according to item B-2, wherein the polyvalent ion is at least one metal ion selected from the group consisting of calcium ion, magnesium ion, aluminum ion, zinc ion, iron ion, copper ion, cobalt ion, nickel ion, and barium ion.
  • Section B-4 The method according to any one of Items B-1 to B-3, wherein the mold is immersed in the rubber latex composition for 15 seconds or more.
  • Section B-5 The manufacturing method according to any one of Items B-1 to B-4, wherein the rubber latex composition contains 0.1 parts by mass or more of a water-soluble polymer having an acidic functional group per 100 parts by mass of rubber.
  • Section B-6 The manufacturing method according to any one of Items B-1 to B-4, wherein the rubber latex composition contains 0.1 parts by mass or more of a water-soluble polymer having an acidic functional group per 100 parts by mass of rubber.
  • Section B-7 The method according to any one of Items B-1 to B-5, wherein the water-soluble polymer having an acidic functional group is an acidic polysaccharide.
  • Section B-7 The method according to Item B-6, wherein the acidic polysaccharide is at least one selected from the group consisting of LM pectin, xanthan gum, ⁇ -carrageenan, ⁇ -carrageenan, and carboxymethylcellulose.
  • Section B-8. The production method according to any one of Items B-1 to B-7, wherein the rubber latex composition is a latex composition containing a water-soluble polymer having an acidic functional group and a chlorosulfonated polyolefin. Section B-9.
  • the present invention makes it possible to stably manufacture relatively thick dip-molded bodies using various types of rubber latex while suppressing thickness variations, entrapment of air bubbles, and loss of latex, thereby providing relatively thick, practical dip-molded bodies.
  • the present invention preferably includes a method for producing a dip-molded body, which includes immersing a mold (also called a molding mold or a film-molding mold) in a rubber latex composition containing a water-soluble polymer having an acidic functional group, and a dip-molded body that can be produced by the method, but is not limited to these, and the present invention includes all of the embodiments disclosed in this specification that can be recognized by a person skilled in the art.
  • the method for producing a dip-molded product included in the present invention includes immersing a mold (also called a molding mold or a film-molding mold) in a rubber latex composition containing a water-soluble polymer having an acidic functional group and rubber, and adhering the rubber latex composition to the surface of the mold, and further includes gelling the water-soluble polymer in the rubber latex composition that has been adhered to the mold. As a result, a rubber film is formed on the surface of the mold, and a dip-molded product can be obtained.
  • This production method is sometimes referred to as the production method of the present invention.
  • this rubber latex composition is sometimes referred to as the latex composition of the present invention.
  • the latex composition of the present invention contains a water-soluble polymer and rubber having an acidic functional group.
  • the rubber latex constituting the latex composition of the present invention is not particularly limited, and examples of the rubber latex that can be used include natural rubber latex, polybutadiene rubber latex, polyisoprene rubber latex, acrylonitrile-butadiene rubber latex, hydrogenated acrylonitrile-butadiene rubber latex, styrene-butadiene rubber latex, hydrogenated styrene-butadiene rubber latex, acrylic rubber latex, ethylene-propylene-diene rubber latex, chloroprene rubber latex, butyl rubber latex, chlorinated polyolefin rubber latex, chlorosulfonated polyolefin rubber latex, fluororubber latex, epichlorohydrin rubber latex, silicone rubber latex, and urethane rubber latex. These may be used alone or in combination of two or more. In particular, the present invention is particularly effective with chlorosulfonated polyolefin rubber latex, which is difficult to
  • the latex composition of the present invention has been described from the viewpoint of the rubber latex that can be used to form the latex composition of the present invention, but it can also be described from the viewpoint of the rubber contained in the latex composition of the present invention as follows. That is, examples of the rubber contained in the latex composition of the present invention include natural rubber, polybutadiene rubber, polyisoprene rubber, acrylonitrile-butadiene rubber, hydrogenated acrylonitrile-butadiene rubber, styrene-butadiene rubber, hydrogenated styrene-butadiene rubber, acrylic rubber, ethylene-propylene-diene rubber, chloroprene rubber, butyl rubber, chlorinated polyolefin rubber, chlorosulfonated polyolefin rubber, fluororubber, epichlorohydrin rubber, silicone rubber, and urethane rubber.
  • Chlorosulfonated polyolefin is a polymer having a structure in which a chlorosulfone group (-SO 2 Cl) and chlorine are bonded to a polyolefin main chain. Chlorosulfonated polyolefin can be obtained by chlorosulfonating and chlorinating polyolefin.
  • Polyolefins are polymers that contain 50% or more by mass of monomer units derived from olefins, such as ethylene, propylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 1-octene, and 1-decene.
  • olefins such as ethylene, propylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 1-octene, and 1-decene.
  • the polyolefin is preferably a polyolefin having at least ethylene and/or propylene as a monomer unit.
  • a homopolymer of ethylene or propylene or a copolymer of ethylene and/or propylene is preferable, and more preferably, for example, polyethylene, polypropylene, ethylene- ⁇ -olefin copolymer, ethylene-vinyl compound copolymer, etc.
  • the ⁇ -olefin include propylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 1-octene, 1-decene, etc.
  • vinyl compound examples include vinyl acetate, vinyl alcohol, acrylic acid, methyl methacrylate, vinyl chloride, acrylonitrile, styrene, vinylcyclohexane, N-isopropylacrylamide, acrolein, vinylene carbonate, maleic anhydride, etc.
  • the polyolefin may be copolymerized with other polymerizable components.
  • other polymerizable components include linear dienes such as 1,3-butadiene, isoprene, 1,4-hexadiene, 1,6-octadiene, 2-methyl-1,5-hexadiene, 6-methyl-1,5-heptadiene, and 7-methyl-1,6-octadiene; and cyclic dienes such as 1,3-cyclohexadiene, 1,4-cyclohexadiene, dicyclopentadiene, 5-vinyl-2-norbornene, 5-ethylidene-2-norbornene, 5-methylene-2-norbornene, and 5-isopropylidene-2-norbornene.
  • Chlorosulfonated polyolefins can be produced by reacting polyolefins with chlorine and sulfurous acid gas, or by reacting polyolefins with sulfuryl chloride in the presence of an amine.
  • the chlorine content in the chlorosulfonated polyolefin is not particularly limited, but from the viewpoint of solubility in a solvent when emulsifying the chlorosulfonated polyolefin and productivity, it is preferably 5 to 60 mass%, more preferably 10 to 50 mass%, and particularly preferably 20 to 40 mass%.
  • the sulfur content in the chlorosulfonated polyolefin is not particularly limited, but it is preferably 0.1 to 5 mass%, more preferably 0.4 to 3 mass%, and particularly preferably 0.6 to 2 mass%.
  • the chlorine content and sulfur content can be calculated by elemental analysis.
  • various methods can be used, such as polymerizing rubber-making monomers emulsified in water using an emulsifier and forming the latex as is, or dissolving solid rubber in an organic solvent, inverting the phases to emulsify and disperse the rubber in water, and then removing the organic solvent to form the latex.
  • the emulsifier used in the production of rubber latex is not particularly limited as long as it can emulsify the monomers used in rubber production.
  • anionic surfactants include aliphatic carboxylates, alkyl ether carboxylates, rosinates, alkyl sulfonates, alkyl benzene sulfonates, and alkyl phosphates.
  • nonionic surfactants include polyoxyalkylene ethers, polyoxyalkylene esters, polyhydric alcohol fatty acid esters, sugar fatty acid esters, and alkyl polyglycosides.
  • anionic-nonionic surfactants include polyoxyalkylene alkyl sulfates, polyoxyalkylene alkyl ether sulfates, and polyoxyalkylene alkyl phenyl ether sulfates. These may be used alone or in combination of two or more.
  • the solids (i.e. rubber) concentration of the rubber latex is preferably 20 to 70% by mass, more preferably 25 to 65% by mass, and particularly preferably 30 to 60% by mass.
  • the solids concentration can be measured in accordance with JIS K 6387-2:2011.
  • the particle size of the rubber in the rubber latex is not particularly limited, but the median particle size measured with a laser diffraction particle size distribution analyzer is preferably 0.05 to 10 ⁇ m, more preferably 0.1 to 5 ⁇ m, and particularly preferably 0.2 to 2.5 ⁇ m. A particle size within this range can result in a more stable rubber latex.
  • the particle size of the rubber can be adjusted by the type and amount of emulsifier, the amount of water used, the operating conditions of the emulsification device, etc.
  • the latex composition of the present invention is a rubber latex composition containing a water-soluble polymer having an acidic functional group and rubber, and can be prepared, for example, by adding a water-soluble polymer having an acidic functional group to the rubber latex.
  • the water-soluble polymer having an acidic functional group may have a part of the acidic functional group neutralized. Even if an attempt is made to neutralize the acidic functional group of a polymer having an acidic functional group, it may be difficult to neutralize all of the acidic functional groups, and commercially available products with the notation of salt are usually "water-soluble polymers having acidic functional groups" in which a part of the acidic functional groups has been neutralized.
  • water-soluble polymers having acidic functional groups polymers having carboxylic acid (salt) groups, sulfonic acid (salt) groups, sulfuric acid (salt) groups, phosphoric acid (salt) groups, phosphonic acid (salt) groups, phenol groups, etc. are preferred.
  • polymers that are soluble in 100 g of water at 50° C. at a rate of 1% by mass or more are preferred.
  • carboxylic acid (salt) and similar notations mean “carboxylic acid” and/or “carboxylate salt”.
  • sodium alginate may be excluded from the water-soluble polymer having an acidic functional group.
  • a rubber latex composition containing sodium alginate is easy to obtain a relatively thin dip-molded product, and therefore the present invention can exert a particularly remarkable effect on a rubber latex containing a "water-soluble polymer having an acidic functional group" other than sodium alginate.
  • water-soluble polymers having acidic functional groups include unsaturated carboxylic acid polymers, unsaturated sulfonic acid polymers, polyamino acids (polypeptides), acidic polysaccharides, etc.
  • Unsaturated carboxylic acid polymers include poly(meth)acrylic acid (salt), ethylene-(meth)acrylic acid (salt) copolymer, poly(styrene-maleic anhydride) copolymer, etc.
  • (meth)acrylic means "methacrylic” and/or "acrylic”.
  • unsaturated sulfonic acid polymers include polystyrene sulfonic acid (salt), polyvinyl sulfonic acid (salt), and poly(2-acrylamido-2-methyl-1-propanesulfonic acid (salt)).
  • polypeptides examples include polyglutamic acid (salt), polyaspartic acid (salt), gelatin, and water-soluble collagen.
  • the acidic polysaccharide may be a naturally occurring acidic polysaccharide or a processed naturally occurring acidic polysaccharide.
  • it may be a naturally occurring acidic polysaccharide that has been deesterified or deacylated, or a naturally occurring acidic polysaccharide that has been chemically modified.
  • it may be a naturally occurring neutral polysaccharide that has been chemically modified to add an acid structure.
  • naturally occurring acidic polysaccharides or processed versions thereof include polysaccharides having uronic acid structures such as galacturonic acid, glucuronic acid, mannuronic acid, and guluronic acid, or sulfated sugar structures.
  • examples of such naturally occurring acidic polysaccharides include pectin (LM pectin, HM pectin), xanthan gum, gellan gum (LA gellan gum, HA gellan gum), algin, gum arabic, ⁇ -carrageenan, ⁇ -carrageenan, tragacanth gum, glucomannan, tremel gum, fucoidan, heparin, hyaluronic acid, rhamsan gum, and diutan gum.
  • pectin LM pectin, HM pectin
  • xanthan gum gellan gum
  • LA gellan gum HA gellan gum
  • algin gum arabic
  • ⁇ -carrageenan ⁇ -carrageenan
  • tragacanth gum glucomannan
  • tremel gum fucoidan
  • fucoidan heparin
  • hyaluronic acid rhamsan gum
  • diutan gum examples of such naturally occurring acidic polys
  • Pectin includes low methoxyl pectin (LM pectin) and high methoxyl pectin (HM pectin).
  • Pectin structure can be broadly classified into two types based on the ratio of galacturonic acid to galacturonic acid methyl ester. It is classified according to the proportion of galacturonic acid methyl ester in the entire pectin molecule (degree of esterification: DE), and when the DE is 50% or more, it is called HM pectin (High Methoxyl Pectin), and when it is less than 50%, it is called LM pectin (Low Methoxyl Pectin).
  • DE degree of esterification
  • HM pectin High Methoxyl Pectin
  • LM pectin Low Methoxyl Pectin
  • pectin found in nature is HM pectin
  • LM pectin is prepared by deesterification treatment.
  • Gellan gum is a natural polysaccharide obtained by fermentation, and is a linear heteropolysaccharide consisting of a repeating structure of four sugars: two glucose units, one glucuronic acid unit, and one rhamnose unit.
  • Gellan gum obtained from fermentation is high acyl gellan gum (HA gellan gum), which has one acyl group on every other repeating unit on the glucose.
  • Low acyl gellan gum (LA gellan gum) can be obtained by removing the acyl groups from the fermentation product (deacylation process).
  • Chemically modified naturally occurring acidic polysaccharides include cationized xanthan gum and amidated pectin.
  • Naturally occurring polysaccharides that have been chemically modified to add an acid structure include carboxymethylcellulose, cellulose succinate, sulfonated cellulose, phosphorylated cellulose, maleic acid modified starch, etc.
  • Acidic polysaccharides can be used alone or in combination of two or more.
  • acidic polysaccharides which have an appropriate amount of acidic functional groups and are prone to gelation
  • the content of the water-soluble polymer having an acidic functional group in the rubber latex composition is preferably 0.1 parts by mass or more per 100 parts by mass of the solids (i.e., rubber) in the rubber latex, and more preferably 0.1 to 5 parts by mass.
  • the upper or lower limit of the range may be, for example, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2, 2.1, 2.2, 2.3, 2.4, 2.5, 2.6, 2.7, 2.8, 2.9, 3, 3.1, 3.2, 3.3, 3.4, 3.5, 3.6, 3.7, 3.8, 3.9, 4, 4.1, 4.2, 4.3, 4.4, 4.5, 4.6, 4.7, 4.8, or 4.9 parts by mass.
  • the range is more preferably 0.2 to 4 parts by mass, and particularly preferably 0.3 to 3 parts by mass.
  • the water-soluble polymer having an acidic functional group may be added during or after the rubber latex is produced. From the viewpoint of the efficiency of rubber latex production, it is preferable to add the water-soluble polymer after the rubber latex is produced.
  • the water-soluble polymer having an acidic functional group may be added as is, as an aqueous solution, or dispersed in alcohol or the like.
  • the rubber latex composition may contain known additives such as antioxidants, defoamers, pH adjusters, chelating agents, vulcanizing agents, vulcanization accelerators, vulcanization accelerator assistants, acid acceptors, film-forming assistants, plasticizers, thickeners, fillers, pigments, etc., within the scope of the present invention.
  • additives such as antioxidants, defoamers, pH adjusters, chelating agents, vulcanizing agents, vulcanization accelerators, vulcanization accelerator assistants, acid acceptors, film-forming assistants, plasticizers, thickeners, fillers, pigments, etc.
  • antioxidants examples include phenol-based antioxidants such as dibutylhydroxytoluene, 2,2'-methylenebis(4-ethyl-6-tert-butylphenol), and 2,5-di-tert-butylhydroquinone; amine-based antioxidants such as N-phenyl-1-naphthylamine and di(4-octylphenyl)amine; phosphorus-based antioxidants such as tris(nonylphenyl)phosphite; sulfur-based antioxidants such as dilauryl thiodipropionate, 2-mercaptobenzimidazole, and nickel dibutyldithiocarbamate; and bisphenol A epoxy resins.
  • phenol-based antioxidants such as dibutylhydroxytoluene, 2,2'-methylenebis(4-ethyl-6-tert-butylphenol), and 2,5-di-tert-butylhydroquinone
  • defoamers examples include oil-based defoamers, mineral oil-based defoamers, silicone-based defoamers, polyether-based defoamers, etc.
  • pH adjusters include sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, ammonia, triethylamine, triethanolamine, tetrabutylammonium hydroxide, hydrochloric acid, sulfuric acid, phosphoric acid, citric acid, acetic acid, etc.
  • Chelating agents include ethylenediaminetetraacetic acid, nitrilotriacetic acid, trans-1,2-diaminocyclohexanetetraacetic acid, diethylenetriaminepentaacetic acid, bis(aminoethyl)glycol ether-N,N,N',N'-tetraacetic acid, N-(2-hydroxyethyl)ethylenediamine-N,N',N'-triacetic acid, dihydroxyethylglycine, 1-hydroxyethane-1,1-diphosphonic acid, gluconic acid, citric acid, malic acid, and tartaric acid.
  • Vulcanizing agents include sulfur such as powdered sulfur, sulfur flowers, precipitated sulfur, and colloidal sulfur; organic peroxides such as di-tert-butyl peroxide and dicumyl peroxide; maleimide compounds such as N,N'-m-phenylene bismaleimide; quinoid compounds such as p-quinone dioxime and p,p'-dibenzoylquinone dioxime; metal compounds such as magnesium oxide and lead oxide; and polyhydric alcohol compounds such as pentaerythritol, dipentaerythritol, sorbitol, and trimethylolpropane.
  • sulfur such as powdered sulfur, sulfur flowers, precipitated sulfur, and colloidal sulfur
  • organic peroxides such as di-tert-butyl peroxide and dicumyl peroxide
  • maleimide compounds such as N,N'-m-phenylene bismaleimide
  • quinoid compounds such as p-quinone dioxime and p,
  • Vulcanization accelerators include diethyldithiocarbamic acid, dibutyldithiocarbamic acid, diphenyldithiocarbamic acid, sodium diethyldithiocarbamate, sodium dibutyldithiocarbamate, sodium diphenyldithiocarbamate, zinc diethyldithiocarbamate, zinc dibutyldithiocarbamate, zinc diphenyldithiocarbamate, 2-mercaptobenzothiazole, zinc 2-mercaptobenzothiazole, di-2-benzothiazolyl disulfide, 2-(4'-morpholinyl) Nodithio)benzothiazole, trimethylthiourea, N,N'-diethylthiourea, 1,3-diphenylguanidine, 1,3-di-o-tolylguanidine, N-cyclohexyl-2-benzothiazolylsulfenamide, N-oxyd
  • vulcanization accelerators examples include metal oxides such as zinc oxide and magnesium oxide, and fatty acids such as stearic acid and palmitic acid.
  • Acid acceptors include metal oxides such as lead oxide, magnesium oxide, zinc oxide, and calcium oxide; metal hydroxides such as magnesium hydroxide, calcium hydroxide, and aluminum hydroxide; clay minerals such as hydrotalcite; and epoxy compounds such as phenyl glycidyl ether, epoxidized soybean oil, epoxidized castor oil, epoxidized polybutadiene, and polyglycidyl methacrylate.
  • film-forming aids include propylene glycol, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, ethylene glycol monoisopropyl ether, ethylene glycol mono n-butyl ether, ethylene glycol mono isobutyl ether, ethylene glycol mono tert-butyl ether, ethylene glycol monophenyl ether, diethylene glycol monoethyl ether, diethylene glycol monopropyl ether, diethylene glycol monoisopropyl ether, diethylene glycol mono n-butyl ether, diethylene glycol mono isobutyl ether, diethylene glycol mono tert-butyl ether, diethylene glycol monophenyl ether, diethylene glycol dimethyl ether, diethylene glycol methyl ethyl ether, triethylene glycol mono
  • Plasticizers include phthalates such as dibutyl phthalate and dioctyl phthalate, aliphatic dibasic acid esters such as dioctyl adipate and dioctyl sebacate, glycerin fatty acid esters such as glycerin diacetomonolaurate, polyesters such as polyethylene adipate and polyhexamethylene succinate, and polyethers such as polyethylene glycol and polyethylene glycol laurate.
  • phthalates such as dibutyl phthalate and dioctyl phthalate
  • aliphatic dibasic acid esters such as dioctyl adipate and dioctyl sebacate
  • glycerin fatty acid esters such as glycerin diacetomonolaurate
  • polyesters such as polyethylene adipate and polyhexamethylene succinate
  • polyethers such as polyethylene glycol and polyethylene glycol laurate.
  • Thickening agents include neutral polysaccharides such as methylcellulose, hydroxyethylcellulose, guar gum, curdlan, and pullulan, and water-soluble polymers such as polyvinyl alcohol, polyethylene oxide, and polyvinylpyrrolidone.
  • Fillers include carbon fiber, cellulose fiber, carbon black, silica, talc, clay, calcium carbonate, titanium oxide, barium sulfate, etc.
  • Pigments include carbon black, titanium oxide, chromium oxide, iron blue, amber, nickel titanium yellow, viridian, cobalt blue, phthalocyanine blue, phthalocyanine green, molybdenum orange, chrome yellow, anthraquinone, quinacridone, etc.
  • the amount of additive is not particularly limited, but is preferably 5 to 30 parts by mass per 100 parts by mass of the solid content (i.e., rubber) in the rubber latex.
  • the viscosity of the latex composition of the present invention at 25°C is preferably 80 mPa ⁇ s or more and 4000 mPa or less, more preferably 90 mPa ⁇ s or more and 3000 mPa ⁇ s or less, and even more preferably 100 mPa ⁇ s or more and 2000 mPa ⁇ s or less.
  • the viscosity of the composition is measured under the following conditions.
  • the measurement spindle may be appropriately selected from LV-1 to LV-4 depending on the viscosity.
  • the measurement rotation speed may be appropriately set if it is outside the range in which viscosity can be measured.
  • Measurement device Brookfield viscometer (DV-II+, manufactured by BROOKFIELD) Measuring spindle: LV-1 to LV-4 Measurement temperature: 25°C Measurement speed: 60 rpm
  • the production method of the present invention includes a step of immersing a mold having a surface temperature of 30° C. or more and less than 100° C. in the latex composition of the present invention to adhere the rubber latex to the surface of the mold.
  • This step is also called a immersion step.
  • the mold for producing the dip-molded body (also called a molding mold or a membrane mold) can be a mold corresponding to the desired three-dimensional shape made of ceramic, metal, glass, plastic, etc.
  • the surface of the mold can be finished with a matte finish or provided with other materials such as fibers or other types of rubber coatings depending on the purpose of the dip-molded body.
  • the temperature of the mold during immersion is 30°C or higher and lower than 100°C.
  • the upper or lower limit of the range (30°C or more and less than 100°C) may be, for example, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, or 99°C.
  • the temperature of the mold during immersion may be 32 to 90° C., 35 to 90° C., 40 to 85° C., 50 to 85° C., 60 to 85° C., 65 to 85° C., 40 to 80° C., 50 to 80° C., 60 to 80° C., 65 to 80° C., or 70 to 80° C.
  • the temperature is preferably 45 to 85° C., more preferably 55 to 85° C., and particularly preferably 62 to 83° C.
  • the temperature of the mold here refers to the surface temperature immediately before immersion, and is measured with a radiation thermometer. More specifically, the temperature of the mold is measured with an infrared radiation thermometer (e.g., infrared radiation thermometer AD-5611A manufactured by A&D Corporation) with emissivity set to 0.95, from a position 20 cm away from the surface of the mold. The time from measurement to immersion is within 3 seconds.
  • infrared radiation thermometer e.g., infrared radiation thermometer AD-5611A manufactured by A&D Corporation
  • emissivity set to 0.95
  • the temperature of the mold can be adjusted using a hot air heater, infrared heater, microwave heater, high frequency heater, etc., and it is preferable to set the heating temperature taking into consideration the cooling time before immersion. It may also be adjusted by combining it with a cooling means such as a cold air blower.
  • the temperature of the rubber latex composition when immersed is not particularly limited, but in the present invention, it is preferable that the temperature of the rubber latex composition when immersed is lower than the temperature of the mold when immersed. Therefore, the temperature of the rubber latex composition when immersed is preferably [the temperature of the mold when immersed - 5] ° C or less, more preferably [the temperature of the mold when immersed - 7] ° C or less, even more preferably [the temperature of the mold when immersed - 20] ° C or less, and particularly preferably [the temperature of the mold when immersed - 30] ° C or less.
  • the temperature of the rubber latex composition when immersed is preferably 10 to 70 ° C, more preferably 15 to 60 ° C, even more preferably 20 to 50 ° C, and particularly preferably 20 to 30 ° C.
  • the temperature of the rubber latex composition during immersion is 10 to 70°C, 15 to 60°C, 20 to 50°C, or 20 to 30°C, and is preferably equal to or lower than [the temperature of the mold during immersion - 5]°C, more preferably equal to or lower than [the temperature of the mold during immersion - 7]°C, even more preferably equal to or lower than [the temperature of the mold during immersion - 20]°C, and particularly preferably equal to or lower than [the temperature of the mold during immersion - 30]°C.
  • the rubber latex composition is at such a temperature during immersion, it is possible to ensure appropriate fluidity and storage stability.
  • the time for immersing the mold in the rubber latex composition can be set so that the resulting film has the desired thickness (preferably, for example, thicker than 0.3 mm). For example, 15 seconds or more is preferable, 20 seconds or more is more preferable, and 30 seconds or more is even more preferable. Also, for example, 15 to 300 seconds is preferable, 20 to 200 seconds is more preferable, and 30 to 150 seconds is even more preferable.
  • the manufacturing method of the present invention includes a step of gelling the water-soluble polymer having an acidic functional group contained in the rubber latex composition that was attached to the mold in the immersion step. This causes a film to form on the surface of the mold. This step is also called the film formation step.
  • Various methods can be used to gel water-soluble polymers having acidic functional groups, depending on the type of water-soluble polymer having acidic functional groups used. Examples include a method of gelling by chemical cross-linking through a chemical reaction, a method of gelling by ionic cross-linking through ionic bonds, and a method of gelling by physical cross-linking through aggregation, crystallization, etc. of polymer chains.
  • a component that causes gelling can be used.
  • a component is also called a coagulant.
  • the coagulant may be, for example, a crosslinking agent for forming chemical crosslinks, or an ion-containing substance for forming ionic crosslinks.
  • a polyfunctional crosslinking agent is preferable as a crosslinking agent for forming chemical crosslinks, and more specifically, for example, ethylene glycol diglycidyl ether, pentaerythritol tetraglycidyl ether, etc.
  • a polyvalent ion-containing substance for example, a polyvalent ion-containing substance is preferable, and more specifically, for example, a substance containing a polyvalent cation such as calcium ion, magnesium ion, aluminum ion, zinc ion, iron ion, copper ion, cobalt ion, nickel ion, barium ion, etc. is preferable.
  • the method of gelling the water-soluble polymer includes reacting the polymer with a multifunctional crosslinking agent such as ethylene glycol diglycidyl ether or pentaerythritol tetraglycidyl ether (for example, reacting at 80°C) to gel the polymer through chemical crosslinking, or contacting the polymer with a multivalent ion to gel the polymer through ionic crosslinking.
  • a multifunctional crosslinking agent such as ethylene glycol diglycidyl ether or pentaerythritol tetraglycidyl ether
  • an acidic polysaccharide When an acidic polysaccharide is used as a water-soluble polymer having an acidic functional group, various methods can be used to gel the acidic polysaccharide depending on the type of acidic polysaccharide used.
  • LM pectin, algin, carboxymethylcellulose (CMC), ⁇ -carrageenan, ⁇ -carrageenan, etc. can be gelled by contacting them with polyvalent ions at a temperature of, for example, 30°C or higher to form ionic crosslinks.
  • Xanthan gum or ⁇ -carrageenan can be gelled by mixing with locust bean gum, heating (for example, 60°C), and then cooling.
  • LA gellan gum can be gelled by contacting it with cations after heating (for example, 40°C). This is because when the sugar chains lose water of hydration due to heating, they change from a random coil to a double helix when cooled, and the charge of the carboxyl groups is neutralized by cations, causing the double helices to associate with each other through hydrogen bonds.
  • HA gellan gum can be gelled by heating (e.g. 80°C) and then cooling. This is because the glyceryl groups in the double helix stabilize the double helix through interaction. Other methods that can be used include gelling by reaction with acids or bases or by contact with alcohol.
  • the method of gelling by contact with polyvalent ions is preferred from the viewpoint of fast gelling speed and strong gel strength.
  • gelling by contact with polyvalent ions it is preferable to gel the water-soluble polymer having acidic functional groups in the rubber latex composition attached to the mold by contacting it with a polyvalent ion-containing substance.
  • the polyvalent ion-containing substance can be said to act as a component that solidifies the water-soluble polymer having acidic functional groups.
  • the polyvalent ion is not particularly limited as long as it is a cation having a valence of two or more, but is preferably at least one metal ion selected from calcium ions, magnesium ions, aluminum ions, zinc ions, iron ions, copper ions, cobalt ions, nickel ions, and barium ions.
  • metal salts containing these ions e.g., halides, sulfates, nitrates, carbonates, acetates, alum, etc.
  • metal salts that are soluble at a concentration of 20 g or more per 100 g of water at 25°C being particularly preferred.
  • salts of potassium ions or sodium ions polysaccharides such as locust bean gum, acids, or polyol compounds can also be used as coagulants.
  • a gelation method using at least one acidic polysaccharide selected from the group consisting of LM pectin, xanthan gum, ⁇ -carrageenan, ⁇ -carrageenan, and carboxymethylcellulose, and a polyvalent ion-containing substance is preferred, and a gelation method using LM pectin and calcium ions is more preferred.
  • the origin of LM pectin is not particularly limited, and it may be derived from apples or citrus fruits, for example.
  • the degree of esterification (DE) of LM pectin is preferably 5 to 45%, more preferably 20 to 40%.
  • the degree of esterification can be measured by titration using an alkaline solution.
  • the degree of esterification can be adjusted by hydrolysis with an acid or alkali.
  • the coagulant may be applied to the mold in advance.
  • a coagulant application step of applying the coagulant to the surface of the mold may be provided before the immersion step.
  • the immersion step and the film formation step proceed simultaneously in parallel while the mold is immersed in the rubber latex composition.
  • the method of attaching the coagulant to the mold in advance is not particularly limited, but includes immersing the mold wetted with a solvent as necessary in the coagulant, spraying the coagulant onto the mold wetted with a solvent as necessary, immersing the mold in a solution of the coagulant (hereinafter also referred to as the coagulant liquid), applying the coagulant liquid to the mold, spraying the coagulant liquid onto the mold, etc.
  • the method of immersing the mold in the coagulant liquid is preferred from the viewpoint of uniform attachment.
  • the solvent used to prepare the coagulation liquid is not particularly limited as long as it can dissolve or disperse the coagulant uniformly, and examples include water, alcohol, etc. From the viewpoint of ease of dissolution, it is preferable to use water.
  • the concentration of the coagulant in the coagulation liquid is not particularly limited, but is preferably 5 to 50% by mass, more preferably 10 to 40% by mass, and particularly preferably 15 to 35% by mass.
  • the immersion time in the coagulant or coagulation liquid is not particularly limited, but is usually preferably 1 to 300 seconds, and more preferably 5 to 100 seconds.
  • the solvent may be removed by drying.
  • the drying temperature can be set appropriately depending on the solvent used, and is preferably 60 to 200°C, and more preferably 90 to 160°C. In this specification, the drying temperature refers to the temperature set in the drying device. There are no particular limitations on the drying time, but it is preferably 1 to 600 seconds, and more preferably 5 to 300 seconds. Drying at a high temperature for a short period of time makes it easier to create a state in which the coagulating agent is uniformly attached to the mold surface.
  • the mold may be immersed in the rubber latex composition, and after the rubber latex composition is adhered, the mold may be brought into contact with the coagulant.
  • the immersion step and the film formation step are carried out sequentially.
  • the mold to which the rubber latex composition is attached may be immersed in the coagulation liquid, or the coagulation liquid may be sprayed onto the mold to which the rubber latex composition is attached. From the viewpoint of obtaining sufficient gel strength, the method of immersing the mold to which the rubber latex composition is attached in the coagulation liquid is preferred.
  • the immersion time in the coagulation liquid is not particularly limited, but is usually preferably 1 to 300 seconds, and more preferably 5 to 100 seconds.
  • the rubber latex composition contains the above-mentioned thickener.
  • a water-soluble polymer having an acidic functional group may be used as a thickener.
  • the drying temperature is not particularly limited, but is preferably 50 to 200°C, more preferably 70 to 180°C, and particularly preferably 90 to 160°C.
  • the drying time is not particularly limited, but is preferably 1 to 120 minutes, more preferably 10 to 100 minutes, and particularly preferably 20 to 60 minutes.
  • the rubber latex composition may be one that has been aged in advance (also called pre-vulcanization).
  • the maturation temperature is not particularly limited, but is preferably 10 to 70°C, and more preferably 20 to 50°C.
  • the temperature here refers to the temperature of the rubber latex composition.
  • the maturation time is not particularly limited, but is preferably 4 to 120 hours, more preferably 10 to 72 hours, and particularly preferably 24 to 48 hours.
  • a rubber latex composition containing additives for vulcanization When a rubber latex composition containing additives for vulcanization is used, it is preferable to vulcanize the rubber component contained in the rubber latex composition by heating after forming a film. Vulcanization may be carried out simultaneously with drying after forming the aforementioned film.
  • the heating temperature for vulcanization is preferably 60 to 200°C, more preferably 80 to 180°C, and particularly preferably 100 to 160°C. By keeping the heating temperature within this range, it is possible to achieve a moderate vulcanization speed and suppress deterioration of the rubber components caused by excessive heating.
  • the heating time for vulcanization can be selected appropriately depending on the heating temperature, and is usually 5 to 120 minutes.
  • washing can be performed by immersing the film in a cleaning solution at 20 to 100°C for about 1 to 60 minutes, which can remove water-soluble impurities (e.g., emulsifiers, water-soluble polymers with acidic functional groups, coagulants, etc.).
  • a cleaning solution at 20 to 100°C for about 1 to 60 minutes, which can remove water-soluble impurities (e.g., emulsifiers, water-soluble polymers with acidic functional groups, coagulants, etc.).
  • Any cleaning solution that can remove water-soluble impurities can be used, such as water, saline, saturated sodium bicarbonate water, and aqueous solutions of chelating agents.
  • chelating agents that can be used here include citric acid, trisodium citrate, gluconic acid, ethylenediaminetetraacetic acid, and sodium tripolyphosphate.
  • Such a cleaning treatment may be carried out before or after the vulcanization. From the viewpoint of more efficient removal of water-soluble impurities, it is preferable to carry out the cleaning treatment before vulcanization.
  • drying may be performed.
  • the drying temperature and drying time are not particularly limited, but can be the same as those in the drying step after the film formation step described above.
  • the dip-molded body can be obtained by removing it from the mold.
  • Methods for removing it include peeling it off by hand, or by using water pressure or compressed air pressure.
  • the immersion molding Before or after the immersion molding is removed from the mold, it may be subjected to a heating treatment or a cleaning treatment.
  • the inner and outer surfaces of the immersion molding may be subjected to a surface treatment such as a chlorination treatment or a coating treatment.
  • the film thickness of the immersion molded article thus obtained can be freely controlled by the amount of the water-soluble polymer having an acidic functional group added, the viscosity of the rubber latex composition, the amount of the coagulant, the immersion time, etc.
  • the manufacturing method of the present invention is more effective and useful when manufacturing a relatively thick immersion molded article, so the film thickness is preferably thicker than 0.3 mm, more preferably more than 0.30 mm and not more than 2.00 mm, or more preferably 0.35 mm to 2.00 mm, and particularly preferably 0.40 mm to 1.00 mm.
  • the immersion molded body obtained in this manner has small unevenness in the film thickness, which is preferable.
  • the unevenness in thickness within the same molded body is preferably less than 50%, more preferably less than 40% or less than 30%, and particularly preferably less than 20%.
  • the thickness and unevenness of the coating are evaluated as follows.
  • the coating of the immersion molded article is divided into approximately thirds in the longitudinal direction, and the thickness is measured at three locations in each of the upper, middle, and lower areas (total of nine locations), and the average thickness of the nine locations is taken as the coating thickness.
  • the unevenness of thickness is evaluated as the difference between the maximum and minimum thicknesses of the nine locations divided by the coating thickness (average thickness of the nine locations) (see formula (1) below). The smaller this value, the smaller the unevenness of thickness, which is preferable.
  • Thickness unevenness (%) (maximum thickness - minimum thickness) / average thickness value x 100 (I)
  • the manufacturing method of the present invention makes it possible to prepare a dip-molded body having a relatively large thickness (preferably greater than 0.30 mm) as described above, while suppressing thickness variation, air bubble entrapment, and latex shedding.
  • the immersion molded product of the present invention is an immersion molded product that contains a water-soluble polymer having an acidic functional group and a rubber, and preferably has a film thickness of more than 0.3 mm and/or a thickness unevenness calculated as described above of 50% or less.
  • the explanation of the manufacturing method of the present invention and the latex composition of the present invention is applicable to the immersion molded product of the present invention.
  • the various characteristics (properties, structures, functions, etc.) described for each embodiment of the present invention above may be combined in any way to specify the present invention.
  • the present invention includes all subject matter consisting of all combinations of each of the combinable constituent elements described in this specification.
  • parts by mass represent the amount relative to 100 parts by mass of the solid content in the rubber latex (i.e. rubber; more specifically, chlorosulfonated polyethylene, hydrogenated nitrile rubber, chloroprene rubber, or styrene butadiene rubber).
  • rubber latex i.e. rubber; more specifically, chlorosulfonated polyethylene, hydrogenated nitrile rubber, chloroprene rubber, or styrene butadiene rubber.
  • all of the compounds used as coagulants were reagents manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.
  • Example 1 Preparation of Rubber Latex Composition> One part by mass of sodium polyacrylate (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd., reagent) was added to chlorosulfonated polyethylene latex (manufactured by Sumitomo Seika Chemicals, trade name "Seporex CSM", solid content concentration 40 mass%) and stirred until completely dissolved to obtain a rubber latex composition.
  • sodium polyacrylate manufactured by Fujifilm Wako Pure Chemical Industries, Ltd., reagent
  • chlorosulfonated polyethylene latex manufactured by Sumitomo Seika Chemicals, trade name "Seporex CSM", solid content concentration 40 mass
  • the ceramic mold was immersed in a 15% by mass aqueous solution of potassium aluminum sulfate for 5 seconds, and then dried in a 100°C air dryer for 300 seconds. The mold was then cooled to 60°C and immersed in the rubber latex composition maintained at 30°C for 30 seconds. The mold was removed from the latex composition and dried in a 100°C air dryer for 60 minutes, and then cooled to room temperature. The film was then peeled off from the mold to obtain a dip-molded body. The obtained dip-molded body was evaluated according to the following criteria.
  • the ceramic mold used was a rectangular thin plate of 20 cm x 8 cm, and the above-mentioned operation using half the length of this mold yielded two rectangular rubber films (dip-molded bodies) of about 10 cm x 8 cm (one on the front and one on the back of the mold).
  • the same operation was also performed on a ceramic mold in the shape of a boat (length 10 cm x width 1.5 cm x height 1 cm) shown in Figure 1, and the ability to follow a complex shape was evaluated.
  • the dip-molded bodies prepared using a ceramic boat-shaped mold were used only for the evaluation of conformability.
  • the thickness was measured at three locations in the upper, middle, and lower areas of the film when the film was divided into three in the longitudinal direction (total of nine locations), and the average thickness of the nine locations was taken as the film thickness.
  • the thickness unevenness was evaluated by dividing the difference between the maximum thickness and the minimum thickness by the film thickness (average thickness of the nine locations) (see formula (1) below), with A being less than 20%, B being 20% or more but less than 40%, C being 40% or more but less than 50%, and D being 50% or more.
  • Thickness unevenness (%) (maximum thickness - minimum thickness) / average thickness value x 100 (I)
  • Examples 2 to 4 Comparative Examples 1 to 4
  • Example 1 The same procedure as in Example 1 was carried out except that the conditions were changed as shown in Table 1, to obtain a dip-molded body.
  • the polyvinyl alcohol used in Comparative Example 4 was a reagent manufactured by Tokyo Chemical Industry Co., Ltd.
  • Example 5 Chlorosulfonated polyethylene latex (manufactured by Sumitomo Seika Chemicals, product name "Seporex CSM", solid content concentration 40 mass%) was added with 15 parts by mass of epoxidized polybutadiene (manufactured by Nippon Soda Co., Ltd., product name "NISSO-PB JP100”) as an acid acceptor, and mixed for 1 hour at 12000 rpm using a homomixer (T.K. Robomix, manufactured by Primix Corporation).
  • a homomixer T.K. Robomix, manufactured by Primix Corporation
  • a ceramic mold was immersed in a 35% by mass aqueous solution of calcium nitrate for 5 seconds, and then dried for 300 seconds in a blast dryer at 160° C. The mold was then allowed to cool to 74° C. and immersed for 30 seconds in the rubber latex composition maintained at 25° C. The mold was removed from the latex composition, dried for 20 minutes in a blast dryer at 100° C., and then heated for another 20 minutes at 160° C. After cooling to room temperature, the film was peeled off from the mold to obtain a dip-molded product.
  • Examples 6 to 23, Comparative Examples 5 to 9 The same operations as in Example 5 were carried out using the ingredients, amounts of ingredients, and immersion method shown in Table 2 to obtain immersion molded bodies.
  • the following commercially available water-soluble polymers were used.
  • Xanthan gum Tokyo Chemical Industry Co., Ltd.
  • Reagent CMC Tokyo Chemical Industry Co., Ltd.
  • Reagent ⁇ -carrageenan Sansho Co., Ltd.
  • product name "GENUVISCO carrageenan type PJ-JPE” Ammonium alginate: Fujifilm Wako Pure Chemical Industries, Ltd.
  • Reagent HA Gellan Gum Sumitomo Pharma Food & Chemical Co., Ltd.
  • Product name "Kelcogel HM" LA Gellan Gum Product name "Kelcogel” manufactured by Sumitomo Pharma Food & Chemical Co., Ltd.
  • Sodium alginate Reagent manufactured by Tokyo Chemical Industry Co., Ltd.
  • Examples 24 to 26 The same procedure as in Example 7 was carried out, except that the LM pectin used was changed to the following LM pectin, to obtain a dip-molded product.
  • the results are shown in Table 3.
  • LM pectin could be gelled under the same conditions as in Example 5, regardless of origin or degree of esterification, and a clean, thick film could be obtained.
  • Example 27 to 29 The same operation as in Example 1 was carried out using the types, compounding ingredients, and compounding amounts of rubber latex shown in Table 4 to obtain dip-molded bodies.
  • the following commercially available rubber latex was used.
  • Hydrogenated nitrile rubber latex Zeon Corporation, product name "Zetpol 2230LX”: listed as HNBR in Table 4.
  • Chloroprene rubber latex manufactured by Tosoh Corporation, product name "Skyprene LA-410”: listed as CR in Table 4.
  • Styrene butadiene rubber latex trade name "Nalstar SR-104" manufactured by Nippon A&L Co., Ltd.: listed as SBR in Table 4.
  • the method of the present invention has the same effect on rubber latex other than chlorosulfonated polyethylene latex, and a clean, thick coating can be obtained with any rubber latex.
  • Example 30 Chlorosulfonated polyethylene latex (manufactured by Sumitomo Seika Chemicals, product name "Seporex CSM", solid content concentration 40 mass%) was added with 15 parts by mass of epoxidized polybutadiene (manufactured by Nippon Soda, product name "NISSO-PB JP100”) as an acid acceptor, and mixed for 1 hour at 12000 rpm using a homomixer (T.K. Robomix, manufactured by Primix Corporation).
  • a homomixer T.K. Robomix, manufactured by Primix Corporation
  • a ceramic mold was heated to 40° C. and immersed in the rubber latex composition maintained at 25° C. for 10 seconds, and then removed from the latex composition.
  • the mold with the latex composition attached was immersed in a coagulation liquid (aqueous solution of 15% by mass of potassium aluminum sulfate) for 30 seconds, and then immersed in warm water at 60° C. for 10 minutes for cleaning.
  • the mold was dried in a 100° C. air dryer for 20 minutes, and then heated at 160° C. for 20 minutes. After cooling to room temperature, the film was peeled off from the mold to obtain a dip-molded product.
  • Example 31 The same procedure as in Example 4 was carried out using the ingredients, amounts thereof, and coagulation liquid shown in Table 5 to obtain dip-molded bodies.
  • a clean, thick coating was also obtained by immersing the mold with the latex composition in a coagulating liquid to cause it to gel.

Abstract

Provided is a method for producing a dip-formed object, the method comprising: dipping a model having a surface temperature of 30-100°C, excluding 100°C, in a rubber latex composition including a rubber and a water-soluble polymer having an acidic functional group to allow the rubber latex composition to adhere to the surface of the model; and causing the water-soluble polymer in the rubber latex composition adherent to the model to gel. This production method can produce a relatively thick dip-formed object while inhibiting thickness unevenness, bubble inclusion, and latex debonding.

Description

浸漬成形体の製造方法および浸漬成形体Manufacturing method of dip-molded body and dip-molded body
　本発明は、浸漬成形体の製造方法、及び浸漬成形体等に関する。より詳しくは、本発明は、ゴムラテックスを用いて浸漬成形（ディップ成形）を行う浸漬成形体の製造方法、及び当該方法により製造され得る浸漬成形体に関する。 The present invention relates to a method for producing a dip-molded body, a dip-molded body, etc. More specifically, the present invention relates to a method for producing a dip-molded body by dip molding using rubber latex, and a dip-molded body that can be produced by the method.
　ゴムラテックスを用いた浸漬成形体（ディップ成形体）の製造は広く行われており、例えば、手袋、サック、カテーテル、バルーン等が製造されている。これらの製品は、所望の形状をした型（成形型または膜成形用型ともいう）をゴムラテックスに浸漬し、所望の厚みになるまでゴム粒子を型に付着させ、その後、型に付着したゴムを必要に応じて加硫することにより製造される。 The manufacture of dip molded articles using rubber latex is widely practiced, and examples of such products include gloves, sacks, catheters, and balloons. These products are manufactured by dipping a mold of the desired shape (also called a molding mold or membrane mold) into rubber latex, adhering rubber particles to the mold until the desired thickness is reached, and then vulcanizing the rubber attached to the mold as necessary.
　様々な浸漬成形方法（ディップ成形方法）が開発されており、直接浸漬法、凝固浸漬法、感熱凝固法、電着浸漬法等が特性に応じて使い分けされている。 Various immersion molding methods (dip molding methods) have been developed, and direct immersion method, coagulation immersion method, heat-sensitive coagulation method, electrochemical deposition immersion method, etc. are used according to the characteristics.
　特許文献１には、塩化カルシウムを含有する凝着液を用いてラテックスから浸漬成形体を製造する方法が開示されている。特許文献２には、感熱化剤とアノード凝着剤を配合した天然ゴムラテックスから浸漬成形体を製造する方法が開示されている。特許文献３には、特定の多糖類を配合したニトリルゴムラテックスからアルコールを凝固剤として浸漬成形体を製造する方法が開示されている。特許文献４には、アルギン酸ナトリウムを配合したクロロスルホン化ポリエチレンラテックスに、カルシウムイオンを付着させた型を浸漬させて浸漬成形体を製造する方法が開示されている。 Patent Document 1 discloses a method for producing a dip-molded body from latex using a coagulating liquid containing calcium chloride. Patent Document 2 discloses a method for producing a dip-molded body from natural rubber latex containing a heat-sensitizing agent and an anodic coagulant. Patent Document 3 discloses a method for producing a dip-molded body from nitrile rubber latex containing a specific polysaccharide, using alcohol as a coagulant. Patent Document 4 discloses a method for producing a dip-molded body by immersing a mold to which calcium ions are attached in chlorosulfonated polyethylene latex containing sodium alginate.
特開平０６－１８２７８８号公報Japanese Patent Application Laid-Open No. 06-182788 特開２０００－０１７００２号公報JP 2000-017002 A 国際公開第２０２０／０６６７４２号International Publication No. 2020/066742 特許第７０３３２４２号公報Patent No. 7033242
　本発明者らは、種々の浸漬方法を検討するなかで、厚い皮膜を製造しようとすると（例えば、皮膜を厚くするために浸漬時間を比較的長くすると）、膜厚のバラつきが生じやすくなったり、気泡が入りやすくなったり（そのために予定した形状と異なる成形体になってしまう）、型からラテックスが脱落しやすくなったりするといった問題が生じやすくなることを見出した。かかる状況下、本発明の目的は、比較的厚い成形体を浸漬成形法で安定して製造する方法を提供することにある。また本発明は、比較的厚い実用的な浸漬成形体を提供することも目的とする。 The inventors, while examining various dipping methods, found that when attempting to produce a thick film (for example, by making the dipping time relatively long in order to thicken the film), problems such as film thickness variations, air bubbles being easily trapped (resulting in a molded product with a different shape than expected), and the latex being easily removed from the mold are likely to occur. Under these circumstances, the object of the present invention is to provide a method for stably producing a relatively thick molded product by the dip molding method. Another object of the present invention is to provide a relatively thick, practical dip molded product.
　本発明は、例えば以下の項に記載の浸漬成形体の製造方法および浸漬成形体を提供する。
項Ａ－１．
　酸性官能基を有する水溶性ポリマー及びゴムを含有するゴムラテックス組成物に、表面温度が３０℃以上１００℃未満の型を浸漬させ、型の表面にゴムラテックス組成物を付着させること、並びに、
　型に付着したゴムラテックス組成物中の前記水溶性ポリマーをゲル化させること、
を含む、浸漬成形体の製造方法。
項Ａ－２．
　型に付着したゴムラテックス組成物中の前記水溶性ポリマーをゲル化させることが、
型に付着したゴムラテックス組成物中の前記水溶性ポリマーを凝固剤と接触させてゲル化させることにより実行される、項Ａ－１に記載の方法。
項Ａ－３．
　前記凝固剤がカルシウムイオン、マグネシウムイオン、アルミニウムイオン、亜鉛イオン、鉄イオン、銅イオン、コバルトイオン、ニッケルイオン、及びバリウムイオンからなる群より選ばれる少なくとも１種の金属イオンを含む多価イオン含有物質である、項Ａ－２に記載の方法。
項Ａ－４．
　前記ゴムラテックス組成物に前記型を浸漬させる時間が１５秒以上である、項Ａ－１～Ａ－３のいずれかに記載の方法。
項Ａ－５．
　前記ゴムラテックス組成物が、ゴム１００質量部に対して酸性官能基を有する水溶性ポリマーを０．１質量部以上含有するゴムラテックス組成物である、項Ａ－１～Ａ－４のいずれかに記載の方法。
項Ａ－６．
　酸性官能基を有する水溶性ポリマーが酸性多糖類である、項Ａ－１～Ａ－５のいずれかに記載の方法。
項Ａ－７．
　酸性多糖類が、ＬＭペクチン、キサンタンガム、κ－カラギーナン、ι－カラギーナン、及びカルボキシメチルセルロースからなる群より選ばれる少なくとも１種である、項Ａ－６に記載の方法。
項Ａ－８．
　ゴムラテックス組成物が、酸性官能基を有する水溶性ポリマー及びクロロスルホン化ポリオレフィンを含有するラテックス組成物である、項Ａ－１～Ａ－７のいずれかに記載の方法。
項Ａ－９．
　型の表面にゴムラテックス組成物を付着させることの前に、
さらに、凝固剤を型に付着させることを含む、項Ａ－１～Ａ－８のいずれかに記載の方法。
項Ａ－１０．
　型の表面にゴムラテックス組成物を付着させることの後に、
表面にゴムラテックス組成物が付着した型に、凝固剤を付着させることを含む、項Ａ－１～Ａ－９のいずれかに記載の方法。
項Ａ－１１．
　酸性官能基を有する水溶性ポリマー及びゴムを含み、膜厚が０．３ｍｍより厚く、次のようにして算出される厚みムラが５０％以下である、浸漬成形体。
［厚みムラ算出方法］
　浸漬成形体の皮膜を長手方向におおよそ３分割したときの上部、中部、下部の範囲でそれぞれ３カ所ずつ（合計９カ所）厚みを測定して、当該９カ所の平均厚みを膜厚とし、さらに、下記式（Ｉ）に記載のように、当該９カ所のうち最大厚みと最小厚みとの差を前記膜厚（９カ所の平均厚み）で除した値を厚みムラとする。
厚みムラ（％）＝（最大厚み－最小厚み）／厚みの平均値×１００　　　（Ｉ） The present invention provides a method for producing a dip-molded body and a dip-molded body, for example, as described in the following sections.
Section A-1.
A mold having a surface temperature of 30° C. or more and less than 100° C. is immersed in a rubber latex composition containing a water-soluble polymer having an acidic functional group and a rubber, thereby adhering the rubber latex composition to the surface of the mold; and
gelling the water-soluble polymer in the rubber latex composition attached to the mold;
A method for producing a dip-molded body comprising the steps of:
Section A-2.
Gelling the water-soluble polymer in the rubber latex composition attached to the mold,
The method according to item A-1, which is carried out by contacting the water-soluble polymer in the rubber latex composition attached to the mold with a coagulant to gel it.
Section A-3.
The method according to item A-2, wherein the coagulant is a polyvalent ion-containing substance containing at least one metal ion selected from the group consisting of calcium ions, magnesium ions, aluminum ions, zinc ions, iron ions, copper ions, cobalt ions, nickel ions, and barium ions.
Section A-4.
The method according to any one of Items A-1 to A-3, wherein the mold is immersed in the rubber latex composition for 15 seconds or longer.
Section A-5.
The method according to any one of Items A-1 to A-4, wherein the rubber latex composition contains 0.1 parts by mass or more of a water-soluble polymer having an acidic functional group per 100 parts by mass of rubber.
Section A-6.
The method according to any one of Items A-1 to A-5, wherein the water-soluble polymer having an acidic functional group is an acidic polysaccharide.
Section A-7.
The method according to Item A-6, wherein the acidic polysaccharide is at least one selected from the group consisting of LM pectin, xanthan gum, κ-carrageenan, ι-carrageenan, and carboxymethylcellulose.
Section A-8.
The method according to any one of Items A-1 to A-7, wherein the rubber latex composition is a latex composition containing a water-soluble polymer having an acidic functional group and a chlorosulfonated polyolefin.
Section A-9.
Prior to depositing the rubber latex composition on the surface of the mold,
The method according to any one of items A-1 to A-8, further comprising attaching a coagulant to the mold.
Section A-10.
After applying the rubber latex composition to the surface of the mold,
The method according to any one of items A-1 to A-9, comprising attaching a coagulant to a mold having the rubber latex composition attached to its surface.
Section A-11.
A dip-molded article comprising a water-soluble polymer having an acidic functional group and a rubber, the thickness of the membrane being greater than 0.3 mm, and the thickness unevenness calculated as follows being 50% or less.
[Thickness Unevenness Calculation Method]
The coating of the immersion molded body is divided into approximately thirds in the longitudinal direction, and the thickness is measured at three locations in each of the upper, middle, and lower areas (total of nine locations). The average thickness of the nine locations is defined as the coating thickness. Furthermore, as shown in the following formula (I), the difference between the maximum and minimum thicknesses among the nine locations is divided by the coating thickness (average thickness of the nine locations) to define the thickness unevenness.
Thickness unevenness (%) = (maximum thickness - minimum thickness) / average thickness value x 100 (I)
項Ｂ－１．
　酸性官能基を有する水溶性ポリマー（ただし、アルギン酸ナトリウムを除く）及びゴムを含有するゴムラテックス組成物に、表面温度が３０℃以上１００℃未満の型を浸漬させ、型の表面にゴムラテックス組成物を付着させること、並びに、
　型に付着したゴムラテックス組成物中の前記水溶性ポリマーをゲル化させること、
を含む、膜厚が０．３ｍｍより厚い浸漬成形体の製造方法。
項Ｂ－２．
　型に付着したゴムラテックス組成物中の前記水溶性ポリマーをゲル化させることが、
型に付着したゴムラテックス組成物中の前記水溶性ポリマーに多価イオン含有物質を適用させてゲル化させることである、項Ｂ－１に記載の製造方法。
項Ｂ－３．
　多価イオンがカルシウムイオン、マグネシウムイオン、アルミニウムイオン、亜鉛イオン、鉄イオン、銅イオン、コバルトイオン、ニッケルイオン、及びバリウムイオンからなる群より選ばれる少なくとも１種の金属イオンである、項Ｂ－２に記載の製造方法。
項Ｂ－４．
　前記ゴムラテックス組成物に前記型を浸漬させる時間が１５秒以上である、項Ｂ－１～Ｂ－３のいずれかに記載の製造方法。
項Ｂ－５．
　前記ゴムラテックス組成物が、ゴム１００質量部に対して酸性官能基を有する水溶性ポリマーが０．１質量部以上含有されるゴムラテックス組成物である、項Ｂ－１～Ｂ－４のいずれかに記載の製造方法。
項Ｂ－６．
　酸性官能基を有する水溶性ポリマーが酸性多糖類である、項Ｂ－１～Ｂ－５のいずれかに記載の製造方法。
項Ｂ－７．
　酸性多糖類が、ＬＭペクチン、キサンタンガム、κ－カラギーナン、ι－カラギーナン、及びカルボキシメチルセルロースからなる群より選ばれる少なくとも１種である、項Ｂ－６に記載の製造方法。
項Ｂ－８．
　ゴムラテックス組成物が、酸性官能基を有する水溶性ポリマー及びクロロスルホン化ポリオレフィンを含有するラテックス組成物である、項Ｂ－１～Ｂ－７のいずれかに記載の製造方法。
項Ｂ－９．
　型の表面にゴムラテックス組成物を付着させることの前に、
さらに、多価イオン含有物質を型に付着させることを含む、項Ｂ－１～Ｂ－８のいずれかに記載の方法。
項Ｂ－１０．
　型の表面にゴムラテックス組成物を付着させることの後に、
表面にゴムラテックス組成物が付着した型に、多価金属イオンを含む溶液に浸漬させることを含む、項Ｂ－１～Ｂ－９のいずれかに記載の方法。
項Ｂ－１１．
　酸性官能基を有する水溶性ポリマー（ただし、アルギン酸ナトリウムを除く）、多価イオン含有物質、及びゴムを含み、次のようにして算出される厚みムラが５０％以下である、浸漬成形体。
［厚みムラ算出方法］
　浸漬成形体の皮膜を長手方向におおよそ３分割したときの上部、中部、下部の範囲でそれぞれ３カ所ずつ（合計９カ所）厚みを測定して、全体の平均を取り、それを膜厚とし、さらに、下記式（Ｉ）に記載のように、当該９カ所のうち最大厚みと最小厚みの差を前記膜厚（９カ所の平均）で除した値を厚みムラとする。
厚みムラ（％）＝（最大厚み－最小厚み）／厚みの平均値×１００　　　（Ｉ） Section B-1.
A mold having a surface temperature of 30° C. or more and less than 100° C. is immersed in a rubber latex composition containing a water-soluble polymer having an acidic functional group (excluding sodium alginate) and rubber, thereby adhering the rubber latex composition to the surface of the mold; and
gelling the water-soluble polymer in the rubber latex composition attached to the mold;
A method for producing a dip-molded body having a film thickness of more than 0.3 mm, comprising:
Section B-2.
Gelling the water-soluble polymer in the rubber latex composition attached to the mold,
The method according to Item B-1, further comprising applying a polyvalent ion-containing substance to the water-soluble polymer in the rubber latex composition adhered to the mold to cause gelation.
Section B-3.
The method according to item B-2, wherein the polyvalent ion is at least one metal ion selected from the group consisting of calcium ion, magnesium ion, aluminum ion, zinc ion, iron ion, copper ion, cobalt ion, nickel ion, and barium ion.
Section B-4.
The method according to any one of Items B-1 to B-3, wherein the mold is immersed in the rubber latex composition for 15 seconds or more.
Section B-5.
The manufacturing method according to any one of Items B-1 to B-4, wherein the rubber latex composition contains 0.1 parts by mass or more of a water-soluble polymer having an acidic functional group per 100 parts by mass of rubber.
Section B-6.
The method according to any one of Items B-1 to B-5, wherein the water-soluble polymer having an acidic functional group is an acidic polysaccharide.
Section B-7.
The method according to Item B-6, wherein the acidic polysaccharide is at least one selected from the group consisting of LM pectin, xanthan gum, κ-carrageenan, ι-carrageenan, and carboxymethylcellulose.
Section B-8.
The production method according to any one of Items B-1 to B-7, wherein the rubber latex composition is a latex composition containing a water-soluble polymer having an acidic functional group and a chlorosulfonated polyolefin.
Section B-9.
Prior to depositing the rubber latex composition on the surface of the mold,
The method according to any one of items B-1 to B-8, further comprising attaching a polyvalent ion-containing substance to the mold.
Section B-10.
After applying the rubber latex composition to the surface of the mold,
The method according to any one of Items B-1 to B-9, comprising immersing a mold having the rubber latex composition attached to its surface in a solution containing a polyvalent metal ion.
Section B-11.
A dip-molded article comprising a water-soluble polymer having an acidic functional group (excluding sodium alginate), a polyvalent ion-containing substance, and a rubber, the thickness unevenness of which, as calculated as follows, is 50% or less.
[Thickness Unevenness Calculation Method]
The coating of the immersion molded body is divided into approximately thirds in the longitudinal direction, and the thickness is measured at three locations in each of the upper, middle, and lower areas (total of nine locations). The overall average is taken and this is regarded as the coating thickness. Furthermore, as shown in the following formula (I), the difference between the maximum and minimum thicknesses of the nine locations is divided by the coating thickness (average of the nine locations) to determine the thickness unevenness.
Thickness unevenness (%) = (maximum thickness - minimum thickness) / average thickness value x 100 (I)
　本発明によれば、様々な種類のゴムラテックスを用いて、比較的厚い浸漬成形体を、厚みのバラつき、気泡の噛みこみ、ラテックスの脱落を抑制しつつ、安定して製造することができ、比較的厚い実用的な浸漬成形体が提供される。 The present invention makes it possible to stably manufacture relatively thick dip-molded bodies using various types of rubber latex while suppressing thickness variations, entrapment of air bubbles, and loss of latex, thereby providing relatively thick, practical dip-molded bodies.
実施例で用いた舟の形状のセラミック製の型を示す。1 shows a boat-shaped ceramic mold used in the examples.
　以下、本発明に包含される各実施形態について、さらに詳細に説明する。本発明は、酸性官能基を有する水溶性ポリマーを含有するゴムラテックス組成物に型（成形型または膜成形用型ともいう）を浸漬させることを含む、浸漬成形体の製造方法や、当該方法により製造され得る浸漬成形体等を好ましく包含するが、これらに限定されるわけではなく、本発明は本明細書に開示され当業者が認識できる全てを包含する。 Each embodiment included in the present invention will be described in more detail below. The present invention preferably includes a method for producing a dip-molded body, which includes immersing a mold (also called a molding mold or a film-molding mold) in a rubber latex composition containing a water-soluble polymer having an acidic functional group, and a dip-molded body that can be produced by the method, but is not limited to these, and the present invention includes all of the embodiments disclosed in this specification that can be recognized by a person skilled in the art.
　本発明に包含される浸漬成形体の製造方法は、酸性官能基を有する水溶性ポリマー及びゴムを含有するゴムラテックス組成物に、型（成形型または膜成形用型ともいう）を浸漬させ、型の表面にゴムラテックス組成物を付着させることを含み、さらに、型に付着したゴムラテックス組成物中の前記水溶性ポリマーをゲル化させることを含む。これにより、型の表面にゴム皮膜が形成され、浸漬成形体を得ることができる。当該製造方法を本発明の製造方法ということがある。また、当該ゴムラテックス組成物を本発明のラテックス組成物ということがある。 The method for producing a dip-molded product included in the present invention includes immersing a mold (also called a molding mold or a film-molding mold) in a rubber latex composition containing a water-soluble polymer having an acidic functional group and rubber, and adhering the rubber latex composition to the surface of the mold, and further includes gelling the water-soluble polymer in the rubber latex composition that has been adhered to the mold. As a result, a rubber film is formed on the surface of the mold, and a dip-molded product can be obtained. This production method is sometimes referred to as the production method of the present invention. Furthermore, this rubber latex composition is sometimes referred to as the latex composition of the present invention.
　本発明のラテックス組成物は、上記の通り、酸性官能基を有する水溶性ポリマー及びゴムを含有する。 As described above, the latex composition of the present invention contains a water-soluble polymer and rubber having an acidic functional group.
　本発明のラテックス組成物を構成するゴムラテックスは、特に限定されず、天然ゴムラテックス、ポリブタジエンゴムラテックス、ポリイソプレンゴムラテックス、アクリロニトリル－ブタジエンゴムラテックス、水素化アクリロニトリル－ブタジエンゴムラテックス、スチレン－ブタジエンゴムラテックス、水素化スチレン-ブタジエンゴムラテックス、アクリルゴムラテックス、エチレン－プロピレン－ジエンゴムラテックス、クロロプレンゴムラテックス、ブチルゴムラテックス、塩素化ポリオレフィンゴムラテックス、クロロスルホン化ポリオレフィンゴムラテックス、フッ素ゴムラテックス、エピクロロヒドリンゴムラテックス、シリコーンゴムラテックス、ウレタンゴムラテックス等を用いることが出来る。これらは単独、または２種以上を混合して用いてもよい。なかでも、ラテックスから厚い皮膜をつくることが難しい、クロロスルホン化ポリオレフィンゴムラテックスに対して、本発明は顕著な効果を発揮することができる。 The rubber latex constituting the latex composition of the present invention is not particularly limited, and examples of the rubber latex that can be used include natural rubber latex, polybutadiene rubber latex, polyisoprene rubber latex, acrylonitrile-butadiene rubber latex, hydrogenated acrylonitrile-butadiene rubber latex, styrene-butadiene rubber latex, hydrogenated styrene-butadiene rubber latex, acrylic rubber latex, ethylene-propylene-diene rubber latex, chloroprene rubber latex, butyl rubber latex, chlorinated polyolefin rubber latex, chlorosulfonated polyolefin rubber latex, fluororubber latex, epichlorohydrin rubber latex, silicone rubber latex, and urethane rubber latex. These may be used alone or in combination of two or more. In particular, the present invention is particularly effective with chlorosulfonated polyolefin rubber latex, which is difficult to form a thick film from.
　なお、上では、本発明のラテックス組成物を、構成し得るゴムラテックスの観点から説明したが、本発明のラテックス組成物に含有されるゴムという観点から、次の様に説明することもできる。すなわち、本発明のラテックス組成物に含有されるゴムとしては、天然ゴム、ポリブタジエンゴム、ポリイソプレンゴム、アクリロニトリル－ブタジエンゴム、水素化アクリロニトリル－ブタジエンゴム、スチレン－ブタジエンゴム、水素化スチレン-ブタジエンゴム、アクリルゴム、エチレン－プロピレン－ジエンゴム、クロロプレンゴム、ブチルゴム、塩素化ポリオレフィンゴム、クロロスルホン化ポリオレフィンゴム、フッ素ゴム、エピクロロヒドリンゴム、シリコーンゴム、ウレタンゴム等を挙げることができる。これらは単独、または２種以上を混合して用いてもよい。なかでも、クロロスルホン化ポリオレフィンゴムラテックスから厚い皮膜をつくることが難しいことから、ゴムとしてクロロスルホン化ポリオレフィンゴムを含有する本発明のラテックス組成物を用いる際には、本発明の製造方法により奏される効果がより有利となり、好ましい。 In the above, the latex composition of the present invention has been described from the viewpoint of the rubber latex that can be used to form the latex composition of the present invention, but it can also be described from the viewpoint of the rubber contained in the latex composition of the present invention as follows. That is, examples of the rubber contained in the latex composition of the present invention include natural rubber, polybutadiene rubber, polyisoprene rubber, acrylonitrile-butadiene rubber, hydrogenated acrylonitrile-butadiene rubber, styrene-butadiene rubber, hydrogenated styrene-butadiene rubber, acrylic rubber, ethylene-propylene-diene rubber, chloroprene rubber, butyl rubber, chlorinated polyolefin rubber, chlorosulfonated polyolefin rubber, fluororubber, epichlorohydrin rubber, silicone rubber, and urethane rubber. These may be used alone or in a mixture of two or more. Among them, since it is difficult to form a thick film from chlorosulfonated polyolefin rubber latex, when using the latex composition of the present invention containing chlorosulfonated polyolefin rubber as rubber, the effect achieved by the manufacturing method of the present invention is more advantageous and is preferable.
　なお、クロロスルホン化ポリオレフィンは、ポリオレフィン主鎖にクロロスルホン基（－ＳＯ２Ｃｌ）及び塩素が結合した構造を有するポリマーである。クロロスルホン化ポリオレフィンは、ポリオレフィンをクロロスルホン化および塩素化して得ることができる。 Chlorosulfonated polyolefin is a polymer having a structure in which a chlorosulfone group (-SO 2 Cl) and chlorine are bonded to a polyolefin main chain. Chlorosulfonated polyolefin can be obtained by chlorosulfonating and chlorinating polyolefin.
　ポリオレフィンは、オレフィンに由来する単量体単位を５０質量％以上有するポリマーであり、当該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、１－ペンテン、１－ヘキセン、４－メチル－１－ペンテン、１－オクテン、１－デセン等が挙げられる。 Polyolefins are polymers that contain 50% or more by mass of monomer units derived from olefins, such as ethylene, propylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 1-octene, and 1-decene.
　ポリオレフィンとしては、少なくともエチレン及び／又はプロピレンを単量体単位として有するポリオレフィンが好ましい。例えば、エチレン又はプロピレンの単独重合体またはエチレン及び／又はプロピレンの共重合体が好ましく、例えば、ポリエチレン、ポリプロピレン、エチレン－α－オレフィン共重合体、エチレン－ビニル化合物共重合体等がより好ましい。前記α－オレフィンとしては、例えば、プロピレン、１－ブテン、１－ペンテン、１－ヘキセン、４－メチル－１－ペンテン、１－オクテン、１－デセン等が挙げられる。前記ビニル化合物としては、例えば、酢酸ビニル、ビニルアルコール、アクリル酸、メタクリル酸メチル、塩化ビニル、アクリロニトリル、スチレン、ビニルシクロヘキサン、Ｎ－イソプロピルアクリルアミド、アクロレイン、ビニレンカーボネート、無水マレイン酸等が挙げられる。 The polyolefin is preferably a polyolefin having at least ethylene and/or propylene as a monomer unit. For example, a homopolymer of ethylene or propylene or a copolymer of ethylene and/or propylene is preferable, and more preferably, for example, polyethylene, polypropylene, ethylene-α-olefin copolymer, ethylene-vinyl compound copolymer, etc. Examples of the α-olefin include propylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 1-octene, 1-decene, etc. Examples of the vinyl compound include vinyl acetate, vinyl alcohol, acrylic acid, methyl methacrylate, vinyl chloride, acrylonitrile, styrene, vinylcyclohexane, N-isopropylacrylamide, acrolein, vinylene carbonate, maleic anhydride, etc.
　ポリオレフィンは、さらに他の重合可能な成分が共重合されてなるものであってもよい。他の重合可能な成分としては、例えば、１，３－ブタジエン、イソプレン、１，４－ヘキサジエン、１，６－オクタジエン、２－メチル－１，５－ヘキサジエン、６－メチル－１，５－ヘプタジエン、７－メチル－１，６－オクタジエンのような鎖状ジエン；１，３－シクロヘキサジエン、１，４－シクロヘキサジエン、ジシクロペンタジエン、５－ビニル－２－ノルボルネン、５－エチリデン－２－ノルボルネン、５－メチレン－２－ノルボルネン、５－イソプロピリデン－２－ノルボルネンのような環状ジエン等が挙げられる。 The polyolefin may be copolymerized with other polymerizable components. Examples of other polymerizable components include linear dienes such as 1,3-butadiene, isoprene, 1,4-hexadiene, 1,6-octadiene, 2-methyl-1,5-hexadiene, 6-methyl-1,5-heptadiene, and 7-methyl-1,6-octadiene; and cyclic dienes such as 1,3-cyclohexadiene, 1,4-cyclohexadiene, dicyclopentadiene, 5-vinyl-2-norbornene, 5-ethylidene-2-norbornene, 5-methylene-2-norbornene, and 5-isopropylidene-2-norbornene.
　ポリオレフィンを塩素および亜硫酸ガスと反応させることにより、またはポリオレフィンをアミン存在下、塩化スルフリルと反応させることにより、クロロスルホン化ポリオレフィンを製造することが出来る。 Chlorosulfonated polyolefins can be produced by reacting polyolefins with chlorine and sulfurous acid gas, or by reacting polyolefins with sulfuryl chloride in the presence of an amine.
　クロロスルホン化ポリオレフィン中に含まれる塩素含有量は特に限定されないが、クロロスルホン化ポリオレフィンを乳化する際の溶媒への溶解性および生産性の観点から、５～６０質量％が好ましく、１０～５０質量％がより好ましく、２０～４０質量％が特に好ましい。また、クロロスルホン化ポリオレフィン中に含まれる硫黄含有量は特に限定されないが、０．１～５質量％が好ましく、０．４～３質量％がより好ましく、０．６～２質量％が特に好ましい。塩素含有量や硫黄含有量は元素分析法により算出することが出来る。 The chlorine content in the chlorosulfonated polyolefin is not particularly limited, but from the viewpoint of solubility in a solvent when emulsifying the chlorosulfonated polyolefin and productivity, it is preferably 5 to 60 mass%, more preferably 10 to 50 mass%, and particularly preferably 20 to 40 mass%. In addition, the sulfur content in the chlorosulfonated polyolefin is not particularly limited, but it is preferably 0.1 to 5 mass%, more preferably 0.4 to 3 mass%, and particularly preferably 0.6 to 2 mass%. The chlorine content and sulfur content can be calculated by elemental analysis.
　ゴムラテックスの製造方法としては、乳化剤を用いて水中に乳化させたゴム製造用モノマーを重合させ、そのままラテックスとする方法や、固形ゴムを有機溶媒に溶解させた後、転相させて水に乳化分散させ、その後有機溶媒を除去しラテックスとする方法等を用いることが出来る。 To manufacture rubber latex, various methods can be used, such as polymerizing rubber-making monomers emulsified in water using an emulsifier and forming the latex as is, or dissolving solid rubber in an organic solvent, inverting the phases to emulsify and disperse the rubber in water, and then removing the organic solvent to form the latex.
　ゴムラテックスの製造で用いられる乳化剤は、ゴム製造用モノマーを乳化させることが出来れば特に制限されず、例えばアニオン系界面活性剤やノニオン系界面活性剤、アニオン－ノニオン系界面活性剤を用いることが出来る。アニオン系界面活性剤としては、例えば脂肪族カルボン酸塩系、アルキルエーテルカルボン酸塩系、ロジン酸塩系、アルキルスルホン酸塩系、アルキルベンゼンスルホン酸塩系、アルキルリン酸塩系などが挙げられる。ノニオン系界面活性剤としては、例えばポリオキシアルキレンエーテル系、ポリオキシアルキレンエステル系、多価アルコール脂肪酸エステル系、糖脂肪酸エステル系、アルキルポリグリコシド系などが挙げられる。アニオン－ノニオン系界面活性剤としては、ポリオキシアルキレンアルキル硫酸塩系、ポリオキシアルキレンアルキルエーテル硫酸塩系、ポリオキシアルキレンアルキルフェニルエーテル硫酸塩系等が挙げられる。これらは単独、または２種以上を併用してもよい。 The emulsifier used in the production of rubber latex is not particularly limited as long as it can emulsify the monomers used in rubber production. For example, anionic surfactants, nonionic surfactants, and anionic-nonionic surfactants can be used. Examples of anionic surfactants include aliphatic carboxylates, alkyl ether carboxylates, rosinates, alkyl sulfonates, alkyl benzene sulfonates, and alkyl phosphates. Examples of nonionic surfactants include polyoxyalkylene ethers, polyoxyalkylene esters, polyhydric alcohol fatty acid esters, sugar fatty acid esters, and alkyl polyglycosides. Examples of anionic-nonionic surfactants include polyoxyalkylene alkyl sulfates, polyoxyalkylene alkyl ether sulfates, and polyoxyalkylene alkyl phenyl ether sulfates. These may be used alone or in combination of two or more.
　ゴムラテックス中の乳化剤の含有量としては、特に制限はないが、得られる製品の機械物性を向上させる観点から、ゴム１００質量部に対し、０．０１～１０質量部程度が好ましい。 There are no particular restrictions on the amount of emulsifier in the rubber latex, but from the perspective of improving the mechanical properties of the resulting product, it is preferable to use about 0.01 to 10 parts by mass per 100 parts by mass of rubber.
　ゴムラテックスの固形分（すなわちゴム）濃度としては、２０～７０質量％が好ましく、２５～６５質量％がより好ましく、３０～６０質量％が特に好ましい。固形分濃度は、ＪＩＳ　Ｋ　６３８７－２：２０１１に従い、測定することができる。 The solids (i.e. rubber) concentration of the rubber latex is preferably 20 to 70% by mass, more preferably 25 to 65% by mass, and particularly preferably 30 to 60% by mass. The solids concentration can be measured in accordance with JIS K 6387-2:2011.
　ゴムラテックス中のゴムの粒子径は、特に限定されないが、レーザー回折式粒度分布計で測定される中位粒子径が０．０５～１０μｍであることが好ましく、０．１～５μｍであることがより好ましく、０．２～２．５μｍであることが特に好ましい。粒子径がこの範囲であると、安定性のより高いゴムラテックスとなり得る。ゴムの粒子径は、乳化剤の種類や量、水の使用量や、乳化装置の運転条件等により調整することが出来る。 The particle size of the rubber in the rubber latex is not particularly limited, but the median particle size measured with a laser diffraction particle size distribution analyzer is preferably 0.05 to 10 μm, more preferably 0.1 to 5 μm, and particularly preferably 0.2 to 2.5 μm. A particle size within this range can result in a more stable rubber latex. The particle size of the rubber can be adjusted by the type and amount of emulsifier, the amount of water used, the operating conditions of the emulsification device, etc.
　本発明のラテックス組成物は、酸性官能基を有する水溶性ポリマー及びゴムを含有するゴムラテックス組成物であり、例えば、前記ゴムラテックスにさらに酸性官能基を有する水溶性ポリマーを加えることで調製することができる。 The latex composition of the present invention is a rubber latex composition containing a water-soluble polymer having an acidic functional group and rubber, and can be prepared, for example, by adding a water-soluble polymer having an acidic functional group to the rubber latex.
　酸性官能基を有する水溶性ポリマーは、その酸性官能基の一部が中和されていてもよい。酸性官能基を有するポリマーの酸性官能基を中和しようとしても、そのすべての酸性官能基を中和することは実現しにくいことがあり、塩の表記の市販品は通常、酸性官能基の一部が中和された「酸性官能基を有する水溶性ポリマー」である。かかる「酸性官能基を有する水溶性ポリマー」としては、カルボン酸（塩）基、スルホン酸（塩）基、硫酸（塩）基、リン酸（塩）基、ホスホン酸（塩）基、フェノール基等を有するポリマーが好ましい。また、５０℃の水１００ｇに対して１質量％以上、溶解可能なポリマーが好ましい。なお、「カルボン酸（塩）」およびそれに類似する表記は、「カルボン酸」及び／又は「カルボン酸塩」を意味する表記である。
　なお、本発明において、アルギン酸ナトリウムは、酸性官能基を有する水溶性ポリマーから除かれてもよい。本発明の検討の過程で、アルギン酸ナトリウムを含有するゴムラテックス組成物は、比較的薄い浸漬成形体を得やすいことが判明しており、そのため、本発明は、アルギン酸ナトリウム以外の「酸性官能基を有する水溶性ポリマー」を含有するゴムラテックスに、特に顕著な効果を発揮することができる。 The water-soluble polymer having an acidic functional group may have a part of the acidic functional group neutralized. Even if an attempt is made to neutralize the acidic functional group of a polymer having an acidic functional group, it may be difficult to neutralize all of the acidic functional groups, and commercially available products with the notation of salt are usually "water-soluble polymers having acidic functional groups" in which a part of the acidic functional groups has been neutralized. As such "water-soluble polymers having acidic functional groups", polymers having carboxylic acid (salt) groups, sulfonic acid (salt) groups, sulfuric acid (salt) groups, phosphoric acid (salt) groups, phosphonic acid (salt) groups, phenol groups, etc. are preferred. In addition, polymers that are soluble in 100 g of water at 50° C. at a rate of 1% by mass or more are preferred. Note that "carboxylic acid (salt)" and similar notations mean "carboxylic acid" and/or "carboxylate salt".
In the present invention, sodium alginate may be excluded from the water-soluble polymer having an acidic functional group. In the course of the study of the present invention, it has been found that a rubber latex composition containing sodium alginate is easy to obtain a relatively thin dip-molded product, and therefore the present invention can exert a particularly remarkable effect on a rubber latex containing a "water-soluble polymer having an acidic functional group" other than sodium alginate.
　酸性官能基を有する水溶性ポリマーとしては、具体的には、例えば、不飽和カルボン酸系ポリマー、不飽和スルホン酸系ポリマー、ポリアミノ酸（ポリペプチド）、酸性多糖類等が挙げられる。 Specific examples of water-soluble polymers having acidic functional groups include unsaturated carboxylic acid polymers, unsaturated sulfonic acid polymers, polyamino acids (polypeptides), acidic polysaccharides, etc.
　不飽和カルボン酸系ポリマーとしては、ポリ（メタ）アクリル酸（塩）、エチレン－（メタ）アクリル酸（塩）共重合体、ポリ（スチレン－無水マレイン酸塩）共重合体等が挙げられる。なお、「（メタ）アクリル」等の表記は、「メタクリル」及び／又は「アクリル」を意味する表記である。 Unsaturated carboxylic acid polymers include poly(meth)acrylic acid (salt), ethylene-(meth)acrylic acid (salt) copolymer, poly(styrene-maleic anhydride) copolymer, etc. The term "(meth)acrylic" means "methacrylic" and/or "acrylic".
　不飽和スルホン酸系ポリマーとしては、ポリスチレンスルホン酸（塩）、ポリビニルスルホン酸（塩）、ポリ（２－アクリルアミド－２－メチル－１－プロパンスルホン酸（塩））等が挙げられる。 Examples of unsaturated sulfonic acid polymers include polystyrene sulfonic acid (salt), polyvinyl sulfonic acid (salt), and poly(2-acrylamido-2-methyl-1-propanesulfonic acid (salt)).
　ポリアミノ酸（ポリペプチド）としては、ポリグルタミン酸（塩）、ポリアスパラギン酸（塩）、ゼラチン、水溶性コラーゲン等が挙げられる。 Examples of polyamino acids (polypeptides) include polyglutamic acid (salt), polyaspartic acid (salt), gelatin, and water-soluble collagen.
　酸性多糖類としては、天然から得られる酸性多糖類であってもよく、天然から得られる酸性多糖類を処理したものであってもよい。例えば、天然から得られる酸性多糖類を脱エステル化処理したり、脱アシル化処理したりしたものや、あるいは天然から得られる酸性多糖類を化学修飾したものであってもよい。あるいはまた、天然から得られる中性多糖類に酸構造を付加するよう化学修飾したものであってもよい。天然から得られる酸性多糖類若しくはそれを処理したものとしては、例えばガラクツロン酸、グルクロン酸、マンヌロン酸、グルロン酸等のウロン酸構造や硫酸化糖構造を有する多糖類が挙げられ、より具体的には例えば、ペクチン（ＬＭペクチン、ＨＭペクチン）、キサンタンガム、ジェランガム（ＬＡジェランガム、ＨＡジェランガム）、アルギン、アラビアガム、κ-カラギーナン、ι-カラギーナン、トラガカントゴム、グルコマンナン、トレメルガム、フコイダン、ヘパリン、ヒアルロン酸、ラムザンガム、ダイユータンガム等が挙げられる。 The acidic polysaccharide may be a naturally occurring acidic polysaccharide or a processed naturally occurring acidic polysaccharide. For example, it may be a naturally occurring acidic polysaccharide that has been deesterified or deacylated, or a naturally occurring acidic polysaccharide that has been chemically modified. Alternatively, it may be a naturally occurring neutral polysaccharide that has been chemically modified to add an acid structure. Examples of naturally occurring acidic polysaccharides or processed versions thereof include polysaccharides having uronic acid structures such as galacturonic acid, glucuronic acid, mannuronic acid, and guluronic acid, or sulfated sugar structures. More specifically, examples of such naturally occurring acidic polysaccharides include pectin (LM pectin, HM pectin), xanthan gum, gellan gum (LA gellan gum, HA gellan gum), algin, gum arabic, κ-carrageenan, ι-carrageenan, tragacanth gum, glucomannan, tremel gum, fucoidan, heparin, hyaluronic acid, rhamsan gum, and diutan gum.
　なお、ペクチンには、低メトキシルペクチン（ＬＭペクチン）及び高メトキシルペクチン（ＨＭペクチン）が包含される。ペクチンの構造はガラクツロン酸とガラクツロン酸メチルエステルの比率により、大きく２つに分類できる。ペクチン分子全体に占めるガラクツロン酸メチルエステルの割合（エステル化度：ＤＥ）により分類され、ＤＥが５０％以上の場合はＨＭペクチン（Ｈｉｇｈ　Ｍｅｔｈｏｘｙｌ　Ｐｅｃｔｉｎ）と、５０％未満の場合はＬＭペクチン（Ｌｏｗ　Ｍｅｔｈｏｘｙｌ　Ｐｅｃｔｉｎ）と、それぞれ呼ばれる。一般的に、自然に存在するペクチンはＨＭペクチンであり、ＬＭペクチンは脱エステル処理により調製される。 Pectin includes low methoxyl pectin (LM pectin) and high methoxyl pectin (HM pectin). Pectin structure can be broadly classified into two types based on the ratio of galacturonic acid to galacturonic acid methyl ester. It is classified according to the proportion of galacturonic acid methyl ester in the entire pectin molecule (degree of esterification: DE), and when the DE is 50% or more, it is called HM pectin (High Methoxyl Pectin), and when it is less than 50%, it is called LM pectin (Low Methoxyl Pectin). Generally, pectin found in nature is HM pectin, and LM pectin is prepared by deesterification treatment.
　また、ジェランガムは発酵によって得られる天然の多糖類であり、２個のグルコース、１個のグルクロン酸、１個のラムノースの４糖が結合した構成の繰り返しからなる直鎖状のヘテロ多糖類である。発酵物から得られるジェランガムは、高アシルジェランガム（ＨＡジェランガム；Ｈｉｇｈ　Ａｃｙｌ　ｇｅｌｌａｎ　ｇｕｍ）であり、グルコース上に繰り返し単位の１つ置きに１個のアシル基を有している。発酵物からアシル基を除去（脱アシル化処理）することで低アシルジェランガム（ＬＡジェランガム、Ｌｏｗ　Ａｃｙｌ　ｇｅｌｌａｎ　ｇｕｍ）が得られる。 Gellan gum is a natural polysaccharide obtained by fermentation, and is a linear heteropolysaccharide consisting of a repeating structure of four sugars: two glucose units, one glucuronic acid unit, and one rhamnose unit. Gellan gum obtained from fermentation is high acyl gellan gum (HA gellan gum), which has one acyl group on every other repeating unit on the glucose. Low acyl gellan gum (LA gellan gum) can be obtained by removing the acyl groups from the fermentation product (deacylation process).
　天然から得られる酸性多糖類を化学修飾したものとしては、カチオン化キサンタンガム、アミド化ペクチン等が挙げられる。天然から得られる多糖類に酸構造を付加するよう化学修飾したものとしては、カルボキシメチルセルロース、コハク酸セルロース、スルホン化セルロース、リン酸化セルロース、マレイン酸変性デンプン等が挙げられる。酸性多糖類は、１種単独で又は２種以上を組み合わせて用いることができる。 Chemically modified naturally occurring acidic polysaccharides include cationized xanthan gum and amidated pectin. Naturally occurring polysaccharides that have been chemically modified to add an acid structure include carboxymethylcellulose, cellulose succinate, sulfonated cellulose, phosphorylated cellulose, maleic acid modified starch, etc. Acidic polysaccharides can be used alone or in combination of two or more.
　なかでも酸性官能基の量が適度で、ゲル化が起こりやすいという観点から、酸性多糖類を用いることが好ましく、ＬＭペクチン、キサンタンガム、κ－カラギーナン、ι－カラギーナン、カルボキシメチルセルロースから選ばれる少なくとも１種を用いることが特に好ましい。 Among these, it is preferable to use acidic polysaccharides, which have an appropriate amount of acidic functional groups and are prone to gelation, and it is particularly preferable to use at least one selected from LM pectin, xanthan gum, κ-carrageenan, ι-carrageenan, and carboxymethylcellulose.
　ゴムラテックス組成物中の酸性官能基を有する水溶性ポリマーの含有量としては、ゴムラテックス中の固形分（すなわちゴム）１００質量部に対して０．１質量部以上が好ましく、０．１～５質量部がより好ましい。当該範囲（０．１～５質量部）の上限または下限は、例えば、０．１、０．２、０．３、０．４、０．５、０．６、０．７、０．８、０．９、１、１．１、１．２、１．３、１．４、１．５、１．６、１．７、１．８、１．９、２、２．１、２．２、２．３、２．４、２．５、２．６、２．７、２．８、２．９、３、３．１、３．２、３．３、３．４、３．５、３．６、３．７、３．８、３．９、４、４．１、４．２、４．３、４．４、４．５、４．６、４．７、４．８、又は４．９質量部であってもよい。例えば当該範囲は、０．２～４質量部がさらに好ましく、０．３～３質量部が特に好ましい。 The content of the water-soluble polymer having an acidic functional group in the rubber latex composition is preferably 0.1 parts by mass or more per 100 parts by mass of the solids (i.e., rubber) in the rubber latex, and more preferably 0.1 to 5 parts by mass. The upper or lower limit of the range (0.1 to 5 parts by mass) may be, for example, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2, 2.1, 2.2, 2.3, 2.4, 2.5, 2.6, 2.7, 2.8, 2.9, 3, 3.1, 3.2, 3.3, 3.4, 3.5, 3.6, 3.7, 3.8, 3.9, 4, 4.1, 4.2, 4.3, 4.4, 4.5, 4.6, 4.7, 4.8, or 4.9 parts by mass. For example, the range is more preferably 0.2 to 4 parts by mass, and particularly preferably 0.3 to 3 parts by mass.
　本発明のラテックス組成物の調製に際しては、酸性官能基を有する水溶性ポリマーを、ゴムラテックスの製造時に添加してもよいし、ゴムラテックス製造後に添加してもよい。ゴムラテックスの製造効率の観点から、ゴムラテックスを製造後に添加する方が好ましい。 When preparing the latex composition of the present invention, the water-soluble polymer having an acidic functional group may be added during or after the rubber latex is produced. From the viewpoint of the efficiency of rubber latex production, it is preferable to add the water-soluble polymer after the rubber latex is produced.
　酸性官能基を有する水溶性ポリマーはそのまま添加してもよいし、水溶液として添加してもよいし、アルコール等に分散させたものを添加してもよい。 The water-soluble polymer having an acidic functional group may be added as is, as an aqueous solution, or dispersed in alcohol or the like.
　ゴムラテックス組成物には、本発明の効果を損なわない範囲で、老化防止剤、消泡剤、ｐＨ調整剤、キレート剤、加硫剤、加硫促進剤、加硫促進助剤、受酸剤、成膜助剤、可塑剤、増粘剤、充填剤、顔料等、公知の添加剤を含んでいてもよい。 The rubber latex composition may contain known additives such as antioxidants, defoamers, pH adjusters, chelating agents, vulcanizing agents, vulcanization accelerators, vulcanization accelerator assistants, acid acceptors, film-forming assistants, plasticizers, thickeners, fillers, pigments, etc., within the scope of the present invention.
　老化防止剤としては、ジブチルヒドロキシトルエン、２,２'－メチレンビス（４－エチル－６－ｔｅｒｔ－ブチルフェノール）、２,５-ジ-ｔｅｒｔ-ブチルハイドロキノン等のフェノール系老化防止剤、Ｎ－フェニル－１－ナフチルアミン、ジ(４－オクチルフェニル)アミン等のアミン系老化防止剤、トリス（ノニルフェニル）ホスファイト等のリン系老化防止剤、チオジプロピオン酸ジラウリル、２-メルカプトベンズイミダゾール、ジブチルジチオカルバミン酸ニッケル等の硫黄系老化防止剤、ビスフェノールＡ型エポキシ樹脂等が挙げられる。 Examples of antioxidants include phenol-based antioxidants such as dibutylhydroxytoluene, 2,2'-methylenebis(4-ethyl-6-tert-butylphenol), and 2,5-di-tert-butylhydroquinone; amine-based antioxidants such as N-phenyl-1-naphthylamine and di(4-octylphenyl)amine; phosphorus-based antioxidants such as tris(nonylphenyl)phosphite; sulfur-based antioxidants such as dilauryl thiodipropionate, 2-mercaptobenzimidazole, and nickel dibutyldithiocarbamate; and bisphenol A epoxy resins.
　消泡剤としては、油脂系消泡剤、ミネラルオイル系消泡剤、シリコーン系消泡剤、ポリエーテル系消泡剤などが挙げられる。 Examples of defoamers include oil-based defoamers, mineral oil-based defoamers, silicone-based defoamers, polyether-based defoamers, etc.
　ｐＨ調整剤としては、水酸化ナトリウム、水酸化カリウム、炭酸ナトリウム、炭酸カリウム、アンモニア、トリエチルアミン、トリエタノールアミン、テトラブチルアンモニウムヒドロキシド、塩酸、硫酸、リン酸、クエン酸、酢酸等が挙げられる。 pH adjusters include sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, ammonia, triethylamine, triethanolamine, tetrabutylammonium hydroxide, hydrochloric acid, sulfuric acid, phosphoric acid, citric acid, acetic acid, etc.
　キレート剤としては、エチレンジアミン四酢酸 、ニトリロ三酢酸、トランス－１，２－ ジアミノシクロヘキサン四酢酸、ジエチレントリアミン五酢酸、ビス（アミノエチル）グリコールエーテル－Ｎ，Ｎ，Ｎ’，Ｎ’－四酢酸、Ｎ－（２－ヒドロキシエチル）エチレンジアミン－Ｎ，Ｎ’，Ｎ’－三酢酸、ジヒドロキシエチルグリシン、１－ヒドロキシエタン－１，１－ジホスホン酸、グルコン酸、クエン酸、リンゴ酸、酒石酸等が挙げられる。 Chelating agents include ethylenediaminetetraacetic acid, nitrilotriacetic acid, trans-1,2-diaminocyclohexanetetraacetic acid, diethylenetriaminepentaacetic acid, bis(aminoethyl)glycol ether-N,N,N',N'-tetraacetic acid, N-(2-hydroxyethyl)ethylenediamine-N,N',N'-triacetic acid, dihydroxyethylglycine, 1-hydroxyethane-1,1-diphosphonic acid, gluconic acid, citric acid, malic acid, and tartaric acid.
　加硫剤としては、粉末硫黄、硫黄華、沈降硫黄、コロイド硫黄等の硫黄、ジ－ｔｅｒｔ－ブチルパーオキシド、ジクミルパーオキシド等の有機過酸化物、Ｎ，Ｎ’－ｍ－フェニレンビスマレイミド等のマレイミド化合物、ｐ－キノンジオキシム、ｐ，ｐ’－ジベンゾイルキノンジオキシム等のキノイド化合物、酸化マグネシウム、酸化鉛等の金属化合物、ペンタエリスリトール、ジペンタエリスリトール、ソルビトール、トリメチロールプロパン等の多価アルコール化合物が挙げられる。 Vulcanizing agents include sulfur such as powdered sulfur, sulfur flowers, precipitated sulfur, and colloidal sulfur; organic peroxides such as di-tert-butyl peroxide and dicumyl peroxide; maleimide compounds such as N,N'-m-phenylene bismaleimide; quinoid compounds such as p-quinone dioxime and p,p'-dibenzoylquinone dioxime; metal compounds such as magnesium oxide and lead oxide; and polyhydric alcohol compounds such as pentaerythritol, dipentaerythritol, sorbitol, and trimethylolpropane.
　加硫促進剤としては、ジエチルジチオカルバミン酸、ジブチルジチオカルバミン酸、ジフェニルジチオカルバミン酸、ジエチルジチオカルバミン酸ナトリウム、ジブチルジチオカルバミン酸ナトリウム、ジフェニルジチオカルバミン酸ナトリウム、ジエチルジチオカルバミン酸亜鉛、ジブチルジチオカルバミン酸亜鉛、ジフェニルジチオカルバミン酸亜鉛、２－メルカプトベンゾチアゾール、２－メルカプトベンゾチアゾール亜鉛、ジ－２－ベンゾチアゾリルジスルフィド、２－（４'－モルホリノジチオ）ベンゾチアゾール、トリメチルチオ尿素、Ｎ,Ｎ'－ジエチルチオ尿素、１,３－ジフェニルグアニジン、１,３－ジ－ｏ－トリルグアニジン、Ｎ－シクロヘキシル－２－ベンゾチアゾリルスルフェンアミド、Ｎ-オキシジエチレン－２－ベンゾチアゾリルスルフェンアミド、テトラメチルチウラムジスルフィド、テトラエチルチウラムジスルフィド、テトラメチルチウラムモノスルフィド、ジペンタメチレンチウラムテトラスルフィド、イソプロピルキサントゲン酸亜鉛等が挙げられる。 Vulcanization accelerators include diethyldithiocarbamic acid, dibutyldithiocarbamic acid, diphenyldithiocarbamic acid, sodium diethyldithiocarbamate, sodium dibutyldithiocarbamate, sodium diphenyldithiocarbamate, zinc diethyldithiocarbamate, zinc dibutyldithiocarbamate, zinc diphenyldithiocarbamate, 2-mercaptobenzothiazole, zinc 2-mercaptobenzothiazole, di-2-benzothiazolyl disulfide, 2-(4'-morpholinyl) Nodithio)benzothiazole, trimethylthiourea, N,N'-diethylthiourea, 1,3-diphenylguanidine, 1,3-di-o-tolylguanidine, N-cyclohexyl-2-benzothiazolylsulfenamide, N-oxydiethylene-2-benzothiazolylsulfenamide, tetramethylthiuram disulfide, tetraethylthiuram disulfide, tetramethylthiuram monosulfide, dipentamethylenethiuram tetrasulfide, zinc isopropylxanthate, etc.
　加硫促進助剤としては、酸化亜鉛、酸化マグネシウム等の金属酸化物、ステアリン酸、パルミチン酸等の脂肪酸等が挙げられる。 Examples of vulcanization accelerators include metal oxides such as zinc oxide and magnesium oxide, and fatty acids such as stearic acid and palmitic acid.
　受酸剤としては、酸化鉛、酸化マグネシウム、酸化亜鉛、酸化カルシウム等の金属酸化物、水酸化マグネシウム、水酸化カルシウム、水酸化アルミニウム等の金属水酸化物、ハイドロタルサイト等の粘土鉱物、フェニルグリシジルエーテル、エポキシ化大豆油、エポキシ化ヒマシ油、エポキシ化ポリブタジエン、ポリグリシジルメタクリレート等のエポキシ化合物等が挙げられる。 Acid acceptors include metal oxides such as lead oxide, magnesium oxide, zinc oxide, and calcium oxide; metal hydroxides such as magnesium hydroxide, calcium hydroxide, and aluminum hydroxide; clay minerals such as hydrotalcite; and epoxy compounds such as phenyl glycidyl ether, epoxidized soybean oil, epoxidized castor oil, epoxidized polybutadiene, and polyglycidyl methacrylate.
　成膜助剤としては、プロピレングリコール、プロピレングリコールモノメチルエーテル、プロピレングリコールモノエチルエーテル、プロピレングリコールモノプロピルエーテル、エチレングリコールモノエチルエーテル、エチレングリコールモノプロピルエーテル、エチレングリコールモノイソプロピルエーテル、エチレングリコールモノｎ－ブチルエーテル、エチレングリコールモノｉｓｏ－ブチルエーテル、エチレングリコールモノｔｅｒｔ－ブチルエーテル、エチレングリコールモノフェニルエーテル、ジエチレングリコールモノエチルエーテル、ジエチレングリコールモノプロピルエーテル、ジエチレングリコールモノイソプロピルエーテル、ジエチレングリコールモノｎ－ブチルエーテル、ジエチレングリコールモノｉｓｏ－ブチルエーテル、ジエチレングリコールモノｔｅｒｔ－ブチルエーテル、ジエチレングリコールモノフェニルエーテル、ジエチレングリコールジメチルエーテル、ジエチレングリコールメチルエチルエーテル、トリエチレングリコールモノブチルエーテル、トリエチレングリコールジメチルエーテル、テトラエチレングリコールジメチルエーテル、ジプロピレングリコールモノn-ブチルエーテル、ジプロピレングリコールジメチルエーテル、トリプロピレングリコールモノメチルエーテル、２，２，４－トリメチル－１，３－ペンタンジオールモノイソブチレート等が挙げられる。 Examples of film-forming aids include propylene glycol, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, ethylene glycol monoisopropyl ether, ethylene glycol mono n-butyl ether, ethylene glycol mono isobutyl ether, ethylene glycol mono tert-butyl ether, ethylene glycol monophenyl ether, diethylene glycol monoethyl ether, diethylene glycol monopropyl ether, diethylene glycol monoisopropyl ether, diethylene glycol mono n-butyl ether, diethylene glycol mono isobutyl ether, diethylene glycol mono tert-butyl ether, diethylene glycol monophenyl ether, diethylene glycol dimethyl ether, diethylene glycol methyl ethyl ether, triethylene glycol monobutyl ether, triethylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, dipropylene glycol mono n-butyl ether, dipropylene glycol dimethyl ether, tripropylene glycol monomethyl ether, and 2,2,4-trimethyl-1,3-pentanediol monoisobutyrate.
　可塑剤としては、ジブチルフタレート、ジオクチルフタレート等のフタル酸エステル類、ジオクチルアジペート、ジオクチルセバケート等の脂肪族二塩基酸エステル類、グリセリンジアセトモノラウレート等のグリセリン脂肪酸エステル類、ポリエチレンアジペート、ポリヘキサメチレンサクシネート等のポリエステル類、ポリエチレングリコール、ポリエチレングリコールラウレート等のポリエーテル類が挙げられる。 Plasticizers include phthalates such as dibutyl phthalate and dioctyl phthalate, aliphatic dibasic acid esters such as dioctyl adipate and dioctyl sebacate, glycerin fatty acid esters such as glycerin diacetomonolaurate, polyesters such as polyethylene adipate and polyhexamethylene succinate, and polyethers such as polyethylene glycol and polyethylene glycol laurate.
　増粘剤としては、メチルセルロース、ヒドロキシエチルセルロース、グアーガム、カードラン、プルラン等の中性多糖類、ポリビニルアルコール、ポリエチレンオキシド、ポリビニルピロリドン等の水溶性ポリマー等が挙げられる。 Thickening agents include neutral polysaccharides such as methylcellulose, hydroxyethylcellulose, guar gum, curdlan, and pullulan, and water-soluble polymers such as polyvinyl alcohol, polyethylene oxide, and polyvinylpyrrolidone.
　充填剤としては、炭素繊維、セルロース繊維、カーボンブラック、シリカ、タルク、クレイ、炭酸カルシウム、酸化チタン、硫酸バリウム等が挙げられる。 Fillers include carbon fiber, cellulose fiber, carbon black, silica, talc, clay, calcium carbonate, titanium oxide, barium sulfate, etc.
　顔料としては、カーボンブラック、酸化チタン、酸化クロム、紺青、アンバー、ニッケルチタンイエロー、ビリジアン、コバルトブルー、フタロシアニンブルー、フタロシアニングリーン、モリブデンオレンジ、クロムイエロー、アントラキノン、キナクドリン等が挙げられる。 Pigments include carbon black, titanium oxide, chromium oxide, iron blue, amber, nickel titanium yellow, viridian, cobalt blue, phthalocyanine blue, phthalocyanine green, molybdenum orange, chrome yellow, anthraquinone, quinacridone, etc.
　ゴムラテックス組成物が添加剤を含む場合の添加剤の量としては特に限定はされないが、ゴムラテックス中の固形分（すなわちゴム）１００質量部に対し、５～３０質量部が好ましい。 When the rubber latex composition contains additives, the amount of additive is not particularly limited, but is preferably 5 to 30 parts by mass per 100 parts by mass of the solid content (i.e., rubber) in the rubber latex.
　本発明のラテックス組成物の粘度は、２５℃において８０ｍＰａ・ｓ以上４０００ｍＰａ以下が好ましく、９０ｍＰａ・ｓ以上３０００ｍＰａ・ｓ以下がより好ましく、１００ｍＰａ・ｓ以上２０００ｍＰａ・ｓ以下がさらに好ましい。 The viscosity of the latex composition of the present invention at 25°C is preferably 80 mPa·s or more and 4000 mPa or less, more preferably 90 mPa·s or more and 3000 mPa·s or less, and even more preferably 100 mPa·s or more and 2000 mPa·s or less.
　なお、本発明において、組成物の粘度は以下の条件で測定した粘度である。以下の条件において、測定スピンドルは、ＬＶ－１～ＬＶ－４の中から粘度に応じて適宜選択してよい。また、測定回転数については、粘度測定可能範囲外の場合、回転数は適宜設定してもよい。 In the present invention, the viscosity of the composition is measured under the following conditions. Under the following conditions, the measurement spindle may be appropriately selected from LV-1 to LV-4 depending on the viscosity. Furthermore, the measurement rotation speed may be appropriately set if it is outside the range in which viscosity can be measured.
［粘度測定条件］
測定装置：ブルックフィールド型粘度計（ＤＶ－ＩＩ＋、ＢＲＯＯＫＦＩＥＬＤ製）
測定スピンドル：ＬＶ－１～ＬＶ－４
測定温度：２５℃
測定回転数：６０ｒｐｍ [Viscosity measurement conditions]
Measurement device: Brookfield viscometer (DV-II+, manufactured by BROOKFIELD)
Measuring spindle: LV-1 to LV-4
Measurement temperature: 25°C
Measurement speed: 60 rpm
　本発明の製造方法は、本発明のラテックス組成物に、表面温度が３０℃以上１００℃未満の型を浸漬させ、型の表面にゴムラテックスを付着させる工程を有する。この工程を浸漬工程ともいう。
　浸漬成形体を製造するための型（成形型または膜成形用型ともいう）は、セラミックや金属、ガラス、プラスチック等の、所望する立体形状に対応した型を使用できる。型の表面は、浸漬成形体の目的に応じて、梨地面に仕上げたり、繊維や別種のゴム皮膜等、別の素材を備えたりしていてもよい。 The production method of the present invention includes a step of immersing a mold having a surface temperature of 30° C. or more and less than 100° C. in the latex composition of the present invention to adhere the rubber latex to the surface of the mold. This step is also called a immersion step.
The mold for producing the dip-molded body (also called a molding mold or a membrane mold) can be a mold corresponding to the desired three-dimensional shape made of ceramic, metal, glass, plastic, etc. The surface of the mold can be finished with a matte finish or provided with other materials such as fibers or other types of rubber coatings depending on the purpose of the dip-molded body.
　上記の通り、浸漬する際の型の温度は３０℃以上１００℃未満である。当該範囲（３０℃以上１００℃未満）の上限または下限は、例えば、３１、３２、３３、３４、３５、３６、３７、３８、３９、４０、４１、４２、４３、４４、４５、４６、４７、４８、４９、５０、５１、５２、５３、５４、５５、５６、５７、５８、５９、６０、６１、６２、６３、６４、６５、６６、６７、６８、６９、７０、７１、７２、７３、７４、７５、７６、７７、７８、７９、８０、８１、８２、８３、８４、８５、８６、８７、８８、８９、９０、９１、９２、９３、９４、９５、９６、９７、９８又は９９℃であってもよい。例えば、浸漬する際の型の温度は、３２～９０℃、３５～９０℃、４０～８５℃、５０～８５℃、６０～８５℃、６５～８５℃、４０～８０℃、５０～８０℃、６０～８０℃、６５～８０℃、７０～８０℃であってよい。該温度は、４５～８５℃が好ましく、５５～８５℃がより好ましく、６２～８３℃が特に好ましい。浸漬する際の型がこのような温度であると、型をラテックス組成物に浸漬した際に、後述の酸性官能基を有する水溶性ポリマーのゲル化が起こりやすくなる温度を維持することができる。
　ここでの型の温度は、浸漬する直前の表面温度を表しており、放射温度計で測定される。より具体的には、型の温度は、赤外線放射温度計（例えばＡ＆Ｄ社製赤外線放射温度計ＡＤ－５６１１Ａ）を用いて、放射率を０．９５に設定し、型の表面から２０ｃｍ離れた位置から測定される。また、測定から浸漬までの時間は３秒以内とする。 As described above, the temperature of the mold during immersion is 30°C or higher and lower than 100°C. The upper or lower limit of the range (30°C or more and less than 100°C) may be, for example, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, or 99°C. For example, the temperature of the mold during immersion may be 32 to 90° C., 35 to 90° C., 40 to 85° C., 50 to 85° C., 60 to 85° C., 65 to 85° C., 40 to 80° C., 50 to 80° C., 60 to 80° C., 65 to 80° C., or 70 to 80° C. The temperature is preferably 45 to 85° C., more preferably 55 to 85° C., and particularly preferably 62 to 83° C. When the mold is at such a temperature during immersion, it is possible to maintain a temperature at which gelation of the water-soluble polymer having an acidic functional group, which will be described later, is likely to occur when the mold is immersed in the latex composition.
The temperature of the mold here refers to the surface temperature immediately before immersion, and is measured with a radiation thermometer. More specifically, the temperature of the mold is measured with an infrared radiation thermometer (e.g., infrared radiation thermometer AD-5611A manufactured by A&D Corporation) with emissivity set to 0.95, from a position 20 cm away from the surface of the mold. The time from measurement to immersion is within 3 seconds.
　型の温度は、熱風加熱装置、赤外線加熱装置、マイクロ波加熱装置、高周波加熱装置等を用いて調整することが出来、加熱温度は浸漬するまでの放冷を考慮して設定することが好ましい。また、冷風機等の冷却手段を組み合わせて調整してもよい。 The temperature of the mold can be adjusted using a hot air heater, infrared heater, microwave heater, high frequency heater, etc., and it is preferable to set the heating temperature taking into consideration the cooling time before immersion. It may also be adjusted by combining it with a cooling means such as a cold air blower.
　浸漬する際のゴムラテックス組成物の温度は特に制限されないが、本発明においては、浸漬する際のゴムラテックス組成物の温度は、浸漬する際の型の温度よりも低い温度であることが好ましい。そこで、浸漬する際のゴムラテックス組成物の温度は、［浸漬する際の型の温度－５］℃以下が好ましく、［浸漬する際の型の温度－７］℃以下がより好ましく、［浸漬する際の型の温度－２０］℃以下がさらに好ましく、［浸漬する際の型の温度－３０］℃以下が特に好ましい。また、浸漬する際のゴムラテックス組成物の温度は、具体的には、１０～７０℃が好ましく、１５～６０℃がより好ましく、２０～５０℃がさらに好ましく、２０～３０℃が特に好ましい。例えば、浸漬する際のゴムラテックス組成物の温度は、１０～７０℃、１５～６０℃、２０～５０℃、または２０～３０℃であり、且つ、［浸漬する際の型の温度－５］℃以下が好ましく、［浸漬する際の型の温度－７］℃以下がより好ましく、［浸漬する際の型の温度－２０］℃以下がさらに好ましく、［浸漬する際の型の温度－３０］℃以下が特に好ましい。浸漬する際のゴムラテックス組成物がこのような温度であると、適度な流動性と保存安定性を確保することが出来る。 The temperature of the rubber latex composition when immersed is not particularly limited, but in the present invention, it is preferable that the temperature of the rubber latex composition when immersed is lower than the temperature of the mold when immersed. Therefore, the temperature of the rubber latex composition when immersed is preferably [the temperature of the mold when immersed - 5] ° C or less, more preferably [the temperature of the mold when immersed - 7] ° C or less, even more preferably [the temperature of the mold when immersed - 20] ° C or less, and particularly preferably [the temperature of the mold when immersed - 30] ° C or less. Furthermore, the temperature of the rubber latex composition when immersed is preferably 10 to 70 ° C, more preferably 15 to 60 ° C, even more preferably 20 to 50 ° C, and particularly preferably 20 to 30 ° C. For example, the temperature of the rubber latex composition during immersion is 10 to 70°C, 15 to 60°C, 20 to 50°C, or 20 to 30°C, and is preferably equal to or lower than [the temperature of the mold during immersion - 5]°C, more preferably equal to or lower than [the temperature of the mold during immersion - 7]°C, even more preferably equal to or lower than [the temperature of the mold during immersion - 20]°C, and particularly preferably equal to or lower than [the temperature of the mold during immersion - 30]°C. When the rubber latex composition is at such a temperature during immersion, it is possible to ensure appropriate fluidity and storage stability.
　型をゴムラテックス組成物に浸漬する時間は、得られる皮膜が所望する厚み（好ましくは、例えば０．３ｍｍより厚い）となるように設定することができる。例えば、１５秒以上が好ましく、２０秒以上がより好ましく、３０秒以上がさらに好ましい。また例えば、１５～３００秒が好ましく、２０～２００秒がより好ましく、３０～１５０秒がさらに好ましい。 The time for immersing the mold in the rubber latex composition can be set so that the resulting film has the desired thickness (preferably, for example, thicker than 0.3 mm). For example, 15 seconds or more is preferable, 20 seconds or more is more preferable, and 30 seconds or more is even more preferable. Also, for example, 15 to 300 seconds is preferable, 20 to 200 seconds is more preferable, and 30 to 150 seconds is even more preferable.
　本発明の製造方法は、浸漬工程で型に付着したゴムラテックス組成物中に含まれる酸性官能基を有する水溶性ポリマーを、ゲル化させる工程を有する。これにより型の表面に皮膜を形成させる。この工程を皮膜形成工程ともいう。 The manufacturing method of the present invention includes a step of gelling the water-soluble polymer having an acidic functional group contained in the rubber latex composition that was attached to the mold in the immersion step. This causes a film to form on the surface of the mold. This step is also called the film formation step.
　酸性官能基を有する水溶性ポリマーをゲル化させる方法としては、用いる酸性官能基を有する水溶性ポリマーの種類により種々の方法が採用でき、例えば、化学反応により化学架橋させゲル化させる方法、イオン結合によりイオン架橋させゲル化させる方法、ポリマー鎖の凝集、結晶化等により物理架橋させゲル化させる方法等が挙げられる。 Various methods can be used to gel water-soluble polymers having acidic functional groups, depending on the type of water-soluble polymer having acidic functional groups used. Examples include a method of gelling by chemical cross-linking through a chemical reaction, a method of gelling by ionic cross-linking through ionic bonds, and a method of gelling by physical cross-linking through aggregation, crystallization, etc. of polymer chains.
　なお、化学反応により化学架橋させゲル化させる場合や、イオン結合によりイオン架橋させゲル化させる場合においては、これらのゲル化を起こすための成分を用いることができる。当該成分を本明細書においては凝固剤とも呼ぶ。 In addition, when gelling is performed by chemical cross-linking through a chemical reaction, or when gelling is performed by ionic cross-linking through ionic bonds, a component that causes gelling can be used. In this specification, such a component is also called a coagulant.
　凝固剤としては、例えば、化学架橋を形成させるための架橋剤や、イオン架橋を形成させるためのイオン含有物質等が挙げられる。用いる酸性官能基を有する水溶性ポリマーの種類にもよるが、化学架橋を形成させるための架橋剤としては、多官能架橋剤が好ましく、より具体的には例えばエチレングリコールジグリシジルエーテルやペンタエリスリトールテトラグリシジルエーテル等が挙げられる。また、イオン架橋を形成させるためのイオン含有物質としては、例えば多価イオン含有物質が好ましく、より具体的には例えばカルシウムイオン、マグネシウムイオン、アルミニウムイオン、亜鉛イオン、鉄イオン、銅イオン、コバルトイオン、ニッケルイオン、バリウムイオン等の多価陽イオンを含有する物質が好ましい。 The coagulant may be, for example, a crosslinking agent for forming chemical crosslinks, or an ion-containing substance for forming ionic crosslinks. Although it depends on the type of water-soluble polymer having an acidic functional group used, a polyfunctional crosslinking agent is preferable as a crosslinking agent for forming chemical crosslinks, and more specifically, for example, ethylene glycol diglycidyl ether, pentaerythritol tetraglycidyl ether, etc. Furthermore, as an ion-containing substance for forming ionic crosslinks, for example, a polyvalent ion-containing substance is preferable, and more specifically, for example, a substance containing a polyvalent cation such as calcium ion, magnesium ion, aluminum ion, zinc ion, iron ion, copper ion, cobalt ion, nickel ion, barium ion, etc. is preferable.
　酸性官能基を有する水溶性ポリマーとして、不飽和カルボン酸系ポリマー、不飽和スルホン酸系ポリマー、またはポリアミノ酸を用いる場合、該水溶性ポリマーをゲル化させる方法としては、エチレングリコールジグリシジルエーテルやペンタエリスリトールテトラグリシジルエーテル等の多官能架橋剤と反応（例えば８０℃で反応）させ化学架橋によりゲル化させる方法や、多価イオンと接触させイオン架橋によりゲル化させる方法が挙げられる。 When an unsaturated carboxylic acid polymer, an unsaturated sulfonic acid polymer, or a polyamino acid is used as the water-soluble polymer having an acidic functional group, the method of gelling the water-soluble polymer includes reacting the polymer with a multifunctional crosslinking agent such as ethylene glycol diglycidyl ether or pentaerythritol tetraglycidyl ether (for example, reacting at 80°C) to gel the polymer through chemical crosslinking, or contacting the polymer with a multivalent ion to gel the polymer through ionic crosslinking.
　酸性官能基を有する水溶性ポリマーとして、酸性多糖類を用いる場合、該酸性多糖類をゲル化させる方法は、用いる酸性多糖類の種類によって種々の方法を用いることが出来る。例えば、ＬＭペクチンやアルギン、カルボキシメチルセルロース（ＣＭＣ）、κ－カラギーナン、ι－カラギーナン等は、例えば３０℃以上程度の温度で多価イオンと接触させることでイオン架橋を形成させゲル化させることが出来る。キサンタンガムやκ－カラギーナンはローカストビーンガムと混合し、加熱（例えば６０℃）後、冷却することによりゲル化させることが出来る。これは、加熱によりほぐれた糖鎖が冷却される際に、キサンタンガムやκ－カラギーナンの二重らせん構造部とローカストビーンガムのランダムコイル構造部が分子間相互作用により結合し、糖鎖の運動が部分的に抑制されることによる。ＬＡジェランガムは加熱（例えば４０℃）後、陽イオンと接触させることによりゲル化させることが出来る。これは、加熱により水和水を失った糖鎖が、冷却される際、ランダムコイル状から二重らせんを形成し、さらに陽イオンによりカルボキシ基の電荷が中和され、二重らせん同士が水素結合により会合することによる。ＨＡジェランガムは加熱（例えば８０℃）後、冷却することによりゲル化することが出来る。これは、二重らせん内のグリセリル基が相互作用により二重らせんを安定化することによる。この他にも、酸や塩基との反応やアルコールとの接触によりゲル化する方法等も用いることが出来る。 When an acidic polysaccharide is used as a water-soluble polymer having an acidic functional group, various methods can be used to gel the acidic polysaccharide depending on the type of acidic polysaccharide used. For example, LM pectin, algin, carboxymethylcellulose (CMC), κ-carrageenan, ι-carrageenan, etc. can be gelled by contacting them with polyvalent ions at a temperature of, for example, 30°C or higher to form ionic crosslinks. Xanthan gum or κ-carrageenan can be gelled by mixing with locust bean gum, heating (for example, 60°C), and then cooling. This is because when the sugar chains loosened by heating are cooled, the double helix structure of xanthan gum or κ-carrageenan and the random coil structure of locust bean gum are bound by intermolecular interactions, partially suppressing the movement of the sugar chains. LA gellan gum can be gelled by contacting it with cations after heating (for example, 40°C). This is because when the sugar chains lose water of hydration due to heating, they change from a random coil to a double helix when cooled, and the charge of the carboxyl groups is neutralized by cations, causing the double helices to associate with each other through hydrogen bonds. HA gellan gum can be gelled by heating (e.g. 80°C) and then cooling. This is because the glyceryl groups in the double helix stabilize the double helix through interaction. Other methods that can be used include gelling by reaction with acids or bases or by contact with alcohol.
　なかでも、ゲル化速度が速く、ゲル強度が強いという観点から、多価イオンと接触させゲル化させる方法が好ましい。そして、多価イオンと接触させゲル化させるにあたっては、型に付着したゴムラテックス組成物中の酸性官能基を有する水溶性ポリマーを多価イオン含有物質と接触させてゲル化させることが好ましい。この場合、多価イオン含有物質は酸性官能基を有する水溶性ポリマーを凝固させる成分としてはたらくということができる。 Among these, the method of gelling by contact with polyvalent ions is preferred from the viewpoint of fast gelling speed and strong gel strength. When gelling by contact with polyvalent ions, it is preferable to gel the water-soluble polymer having acidic functional groups in the rubber latex composition attached to the mold by contacting it with a polyvalent ion-containing substance. In this case, the polyvalent ion-containing substance can be said to act as a component that solidifies the water-soluble polymer having acidic functional groups.
　多価イオンとしては、２価以上の価数を有する陽イオンであれば特に限定されないが、カルシウムイオン、マグネシウムイオン、アルミニウムイオン、亜鉛イオン、鉄イオン、銅イオン、コバルトイオン、ニッケルイオン、バリウムイオンから選ばれる少なくとも１種の金属イオンであることが好ましい。 The polyvalent ion is not particularly limited as long as it is a cation having a valence of two or more, but is preferably at least one metal ion selected from calcium ions, magnesium ions, aluminum ions, zinc ions, iron ions, copper ions, cobalt ions, nickel ions, and barium ions.
　よって、多価イオン含有物質としては、これらのイオンを含む金属塩（例えば、ハロゲン化物、硫酸塩、硝酸塩、炭酸塩、酢酸塩、ミョウバン等）が好ましく、水溶性の金属塩を用いることがより好ましく、２５℃の水１００ｇに対し２０ｇ以上の濃度で溶解可能な金属塩が特に好ましい。 Therefore, as the polyvalent ion-containing substance, metal salts containing these ions (e.g., halides, sulfates, nitrates, carbonates, acetates, alum, etc.) are preferred, and it is more preferable to use water-soluble metal salts, with metal salts that are soluble at a concentration of 20 g or more per 100 g of water at 25°C being particularly preferred.
　また、用いる酸性多糖類によっては、凝固剤としてカリウムイオンやナトリウムイオンからなる塩、ローカストビーンガム等の多糖類、酸、若しくはポリオール化合物等を用いることもできる。 Depending on the acidic polysaccharide used, salts of potassium ions or sodium ions, polysaccharides such as locust bean gum, acids, or polyol compounds can also be used as coagulants.
　なかでも、ゲル化速度が速く、ゲル強度が強いという観点から、ＬＭペクチン、キサンタンガム、κ－カラギーナン、ι－カラギーナン、及びカルボキシメチルセルロースからなる群より選ばれる少なくとも１種の酸性多糖類と、多価イオン含有物質とを用いるゲル化方法が好ましく、ＬＭペクチンとカルシウムイオンとを用いるゲル化方法がより好ましい。ＬＭペクチンは、その由来は特に限定されず、例えばリンゴ由来であってもよいし、柑橘由来であってもよい。またＬＭペクチンのエステル化度（ＤＥ）は５～４５％が好ましく、２０～４０％がより好ましい。エステル化度はアルカリ溶液による滴定法で測定することが出来る。当該エステル化度は、酸やアルカリにより加水分解を行うことで調整することが出来る。 Among them, from the viewpoint of fast gelation speed and strong gel strength, a gelation method using at least one acidic polysaccharide selected from the group consisting of LM pectin, xanthan gum, κ-carrageenan, ι-carrageenan, and carboxymethylcellulose, and a polyvalent ion-containing substance is preferred, and a gelation method using LM pectin and calcium ions is more preferred. The origin of LM pectin is not particularly limited, and it may be derived from apples or citrus fruits, for example. The degree of esterification (DE) of LM pectin is preferably 5 to 45%, more preferably 20 to 40%. The degree of esterification can be measured by titration using an alkaline solution. The degree of esterification can be adjusted by hydrolysis with an acid or alkali.
　凝固剤はあらかじめ型に付着させてもよい。すなわち、浸漬工程の前に、型の表面に凝固剤を付着させる凝固剤付着工程を備えてもよい。この場合、浸漬工程と皮膜形成工程は、ゴムラテックス組成物中に型を浸漬している間に同時並行で進行する。 The coagulant may be applied to the mold in advance. In other words, a coagulant application step of applying the coagulant to the surface of the mold may be provided before the immersion step. In this case, the immersion step and the film formation step proceed simultaneously in parallel while the mold is immersed in the rubber latex composition.
　凝固剤をあらかじめ型に付着させる方法としては、特に限定されないが、必要に応じて溶媒で濡らした型を凝固剤に浸漬する方法、必要に応じて溶媒で濡らした型に凝固剤を噴霧する方法、凝固剤の溶液（以下、凝固液ともいう）に型を浸漬する方法、凝固液を型に塗布する方法、凝固液を型に噴霧する方法等が挙げられる。なかでも、均一に付着させる観点から、凝固液に型を浸漬する方法が好ましい。 　The method of attaching the coagulant to the mold in advance is not particularly limited, but includes immersing the mold wetted with a solvent as necessary in the coagulant, spraying the coagulant onto the mold wetted with a solvent as necessary, immersing the mold in a solution of the coagulant (hereinafter also referred to as the coagulant liquid), applying the coagulant liquid to the mold, spraying the coagulant liquid onto the mold, etc. Among these, the method of immersing the mold in the coagulant liquid is preferred from the viewpoint of uniform attachment.
　凝固液の調製に用いられる溶媒としては、凝固剤を均一に溶解、または分散可能であれば特に制限されず、例えば、水、アルコール等が挙げられる。溶解しやすさの観点から水を用いることが好ましい。 The solvent used to prepare the coagulation liquid is not particularly limited as long as it can dissolve or disperse the coagulant uniformly, and examples include water, alcohol, etc. From the viewpoint of ease of dissolution, it is preferable to use water.
　凝固液における凝固剤の濃度としては、特に限定はされないが、５～５０質量％が好ましく、１０～４０質量％がより好ましく、１５～３５質量％が特に好ましい。 The concentration of the coagulant in the coagulation liquid is not particularly limited, but is preferably 5 to 50% by mass, more preferably 10 to 40% by mass, and particularly preferably 15 to 35% by mass.
　凝固剤または凝固液への浸漬時間としては、特に限定されないが、通常１～３００秒が好ましく、５～１００秒がより好ましい。 The immersion time in the coagulant or coagulation liquid is not particularly limited, but is usually preferably 1 to 300 seconds, and more preferably 5 to 100 seconds.
　凝固液を使用した場合は、溶媒を乾燥により除去してもよい。乾燥温度としては、使用する溶媒に応じて適宜設定することができ、例えば６０～２００℃が好ましく、９０～１６０℃がより好ましい。なお、本明細書における乾燥温度は、乾燥装置における設定温度を表す。また、乾燥時間は特に限定されないが、１～６００秒が好ましく、５～３００秒がより好ましい。高温、短時間で乾燥させることにより、型表面に均一に凝固剤が付着した状態を作りやすくなる。 If a coagulating liquid is used, the solvent may be removed by drying. The drying temperature can be set appropriately depending on the solvent used, and is preferably 60 to 200°C, and more preferably 90 to 160°C. In this specification, the drying temperature refers to the temperature set in the drying device. There are no particular limitations on the drying time, but it is preferably 1 to 600 seconds, and more preferably 5 to 300 seconds. Drying at a high temperature for a short period of time makes it easier to create a state in which the coagulating agent is uniformly attached to the mold surface.
　本発明の製造方法の実施形態としては、型をゴムラテックス組成物に浸漬させ、ゴムラテックス組成物を付着させた後に、凝固剤と接触させてもよい。この場合、浸漬工程と皮膜形成工程は順次行われる。 In one embodiment of the manufacturing method of the present invention, the mold may be immersed in the rubber latex composition, and after the rubber latex composition is adhered, the mold may be brought into contact with the coagulant. In this case, the immersion step and the film formation step are carried out sequentially.
　凝固剤と接触させる方法としては、例えば、ゴムラテックス組成物を付着させた型を凝固液に浸漬してもよいし、ゴムラテックス組成物を付着させた型に凝固液を噴霧してもよい。十分なゲル強度を得る観点から、ゴムラテックス組成物を付着させた型を凝固液に浸漬する方法が好ましい。 As a method for contacting with the coagulant, for example, the mold to which the rubber latex composition is attached may be immersed in the coagulation liquid, or the coagulation liquid may be sprayed onto the mold to which the rubber latex composition is attached. From the viewpoint of obtaining sufficient gel strength, the method of immersing the mold to which the rubber latex composition is attached in the coagulation liquid is preferred.
　凝固液へ浸漬する場合の浸漬時間としては、特に限定されないが、通常１～３００秒が好ましく、５～１００秒がより好ましい。 The immersion time in the coagulation liquid is not particularly limited, but is usually preferably 1 to 300 seconds, and more preferably 5 to 100 seconds.
　この形態を採用する場合、より厚い皮膜を得る観点から、ゴムラテックス組成物は、前述の増粘剤を含有することが好ましい。また、酸性官能基を有する水溶性ポリマーを増粘剤として用いてもよい。 When this form is adopted, from the viewpoint of obtaining a thicker film, it is preferable that the rubber latex composition contains the above-mentioned thickener. In addition, a water-soluble polymer having an acidic functional group may be used as a thickener.
　皮膜を形成させた後に、乾燥を行うことが好ましい。この際における乾燥温度は、特に限定されないが、５０～２００℃が好ましく、７０～１８０℃がより好ましく、９０～１６０℃が特に好ましい。また、乾燥時間は、特に限定されないが、１～１２０分が好ましく、１０～１００分がより好ましく、２０～６０分が特に好ましい。 After the film is formed, it is preferable to dry it. The drying temperature is not particularly limited, but is preferably 50 to 200°C, more preferably 70 to 180°C, and particularly preferably 90 to 160°C. The drying time is not particularly limited, but is preferably 1 to 120 minutes, more preferably 10 to 100 minutes, and particularly preferably 20 to 60 minutes.
　ゴムラテックス組成物に、加硫のための添加剤を含有するものを用いる場合には、ゴムラテックス組成物として、予め熟成（前加硫ともいう）させたものを用いてもよい。 When using a rubber latex composition that contains additives for vulcanization, the rubber latex composition may be one that has been aged in advance (also called pre-vulcanization).
　熟成温度は、特に限定されないが、１０～７０℃が好ましく、２０～５０℃がより好ましい。ここでいう温度は、ゴムラテックス組成物の温度を表す。また、熟成時間は、特に限定されないが、４～１２０時間が好ましく、１０～７２時間がより好ましく、２４～４８時間が特に好ましい。 The maturation temperature is not particularly limited, but is preferably 10 to 70°C, and more preferably 20 to 50°C. The temperature here refers to the temperature of the rubber latex composition. The maturation time is not particularly limited, but is preferably 4 to 120 hours, more preferably 10 to 72 hours, and particularly preferably 24 to 48 hours.
　ゴムラテックス組成物に、加硫のための添加剤を含有するものを用いる場合には、皮膜を形成させた後、加熱することにより、ゴムラテックス組成物に含まれるゴム成分を加硫させることが好ましい。加硫は、前述の皮膜を形成させた後の乾燥と同時に行ってもよい。 When a rubber latex composition containing additives for vulcanization is used, it is preferable to vulcanize the rubber component contained in the rubber latex composition by heating after forming a film. Vulcanization may be carried out simultaneously with drying after forming the aforementioned film.
　加硫のための加熱温度は、６０～２００℃が好ましく、８０～１８０℃がより好ましく、１００～１６０℃が特に好ましい。加熱温度をこの範囲にすることにより、適度な加硫速度とするとともに、過剰な加熱によるゴム成分の劣化を抑制することが出来る。加硫のための加熱時間は、加熱温度に応じて適宜選択すればよく、通常、５～１２０分である。 The heating temperature for vulcanization is preferably 60 to 200°C, more preferably 80 to 180°C, and particularly preferably 100 to 160°C. By keeping the heating temperature within this range, it is possible to achieve a moderate vulcanization speed and suppress deterioration of the rubber components caused by excessive heating. The heating time for vulcanization can be selected appropriately depending on the heating temperature, and is usually 5 to 120 minutes.
　必要に応じて、型に形成される皮膜を洗浄することが好ましい。洗浄は２０～１００℃の洗浄液に１～６０分程度浸漬することにより、皮膜から水溶性不純物（例えば、乳化剤、酸性官能基を有する水溶性ポリマー、凝固剤など）を除去することが出来る。洗浄液としては、水溶性不純物を除去可能なものであればよく、水、食塩水、飽和重曹水、キレート剤水溶液等を用いることが出来る。ここで用いられるキレート剤としては、クエン酸、クエン酸三ナトリウム、グルコン酸、エチレンジアミン四酢酸、トリポリリン酸ナトリウム等が挙げられる。 If necessary, it is preferable to wash the film formed on the mold. Washing can be performed by immersing the film in a cleaning solution at 20 to 100°C for about 1 to 60 minutes, which can remove water-soluble impurities (e.g., emulsifiers, water-soluble polymers with acidic functional groups, coagulants, etc.). Any cleaning solution that can remove water-soluble impurities can be used, such as water, saline, saturated sodium bicarbonate water, and aqueous solutions of chelating agents. Examples of chelating agents that can be used here include citric acid, trisodium citrate, gluconic acid, ethylenediaminetetraacetic acid, and sodium tripolyphosphate.
　このような洗浄処理は、前記加硫させる前に行ってもよく、また加硫後に行なってもよい。より効率的に水溶性不純物を除去できる観点から、加硫させる前に行なうことが好ましい。 Such a cleaning treatment may be carried out before or after the vulcanization. From the viewpoint of more efficient removal of water-soluble impurities, it is preferable to carry out the cleaning treatment before vulcanization.
　洗浄した後に、さらに乾燥を行ってもよい。この際における乾燥温度、乾燥時間は、特に限定されないが、前述した、皮膜形成工程後の乾燥工程における乾燥温度、乾燥時間と同様とすることができる。 After washing, drying may be performed. The drying temperature and drying time are not particularly limited, but can be the same as those in the drying step after the film formation step described above.
　このようにして皮膜を形成した後、型から脱着することによって、浸漬成形体を得ることができる。脱着方法としては、手で剥したり、水圧や圧縮空気の圧力により剥したりする方法が挙げられる。 After the coating is formed in this way, the dip-molded body can be obtained by removing it from the mold. Methods for removing it include peeling it off by hand, or by using water pressure or compressed air pressure.
　浸漬成形体を型から脱着する前、または脱着した後に、さらに加熱処理、洗浄処理を行ってもよい。また、浸漬成形体を型から脱着した後に、浸漬成形体の内側や外側の表面に、塩素化処理やコーティング処理などの表面処理を行ってもよい。 Before or after the immersion molding is removed from the mold, it may be subjected to a heating treatment or a cleaning treatment. In addition, after the immersion molding is removed from the mold, the inner and outer surfaces of the immersion molding may be subjected to a surface treatment such as a chlorination treatment or a coating treatment.
　このようにして得られる浸漬成形体の膜厚は、酸性官能基を有する水溶性ポリマーの添加量やゴムラテックス組成物の粘度、凝固剤の量や浸漬時間等により任意に制御することができる。本発明の製造方法は、比較的厚い浸漬成形体を製造する際に、より効果的であり、より有用であるので、該膜厚は、０．３ｍｍより厚いことが好ましく、０．３０ｍｍ超え２．００ｍｍ以下または０．３５ｍｍ～２．００ｍｍがより好ましく、０．４０ｍｍ～１．００ｍｍが特に好ましい。さらにいえば、本発明の製造方法においては、特に浸漬工程において、最終的に得られる当該浸漬成形体の皮膜厚さが前記のようになる程度の時間、浸漬させることが好ましい。 The film thickness of the immersion molded article thus obtained can be freely controlled by the amount of the water-soluble polymer having an acidic functional group added, the viscosity of the rubber latex composition, the amount of the coagulant, the immersion time, etc. The manufacturing method of the present invention is more effective and useful when manufacturing a relatively thick immersion molded article, so the film thickness is preferably thicker than 0.3 mm, more preferably more than 0.30 mm and not more than 2.00 mm, or more preferably 0.35 mm to 2.00 mm, and particularly preferably 0.40 mm to 1.00 mm. Furthermore, in the manufacturing method of the present invention, particularly in the immersion step, it is preferable to immerse the immersion molded article for a time period during which the film thickness of the finally obtained immersion molded article is as described above.
　また、このようにして得られる浸漬成形体は、膜厚のムラが小さく、好ましい。同一成形体の中の厚みムラは、５０％未満が好ましく、４０％未満もしくは３０％未満がより好ましく、２０％未満が特に好ましい。 Furthermore, the immersion molded body obtained in this manner has small unevenness in the film thickness, which is preferable. The unevenness in thickness within the same molded body is preferably less than 50%, more preferably less than 40% or less than 30%, and particularly preferably less than 20%.
　なお、皮膜の膜厚および厚みのムラについては、以下のようにして評価される。浸漬成形体の皮膜を長手方向におおよそ３分割したときの上部、中部、下部の範囲でそれぞれ３カ所ずつ（合計９カ所）厚みを測定して、当該９カ所の平均厚みを膜厚とする。厚みムラは、９カ所のうち最大厚みと最小厚みとの差を前記膜厚（９カ所の平均厚み）で除した値（下記式（１）参照）で評価する。当該値が小さいほど厚みムラが小さく好ましい。
厚みムラ（％）＝（最大厚み－最小厚み）／厚みの平均値×１００　　　（Ｉ） The thickness and unevenness of the coating are evaluated as follows. The coating of the immersion molded article is divided into approximately thirds in the longitudinal direction, and the thickness is measured at three locations in each of the upper, middle, and lower areas (total of nine locations), and the average thickness of the nine locations is taken as the coating thickness. The unevenness of thickness is evaluated as the difference between the maximum and minimum thicknesses of the nine locations divided by the coating thickness (average thickness of the nine locations) (see formula (1) below). The smaller this value, the smaller the unevenness of thickness, which is preferable.
Thickness unevenness (%) = (maximum thickness - minimum thickness) / average thickness value x 100 (I)
　本発明の製造方法によれば、上記のような比較的厚い厚み（好ましくは０．３０ｍｍより厚い）を有し、且つ厚みのバラつき、気泡の噛みこみ、ラテックスの脱落の抑制された浸漬成形体を調製することができる。 The manufacturing method of the present invention makes it possible to prepare a dip-molded body having a relatively large thickness (preferably greater than 0.30 mm) as described above, while suppressing thickness variation, air bubble entrapment, and latex shedding.
　本発明の浸漬成形体は、酸性官能基を有する水溶性ポリマー及びゴムを含む浸漬成形体であり、好ましくは、さらに、膜厚が０．３ｍｍより厚く、及び／又は、上記のようにして算出される厚みムラが５０％以下である、浸漬成形体である。本発明の浸漬成形体についての説明は、本発明の製造方法や本発明のラテックス組成物について行った説明が、そのまま当てはまる。 The immersion molded product of the present invention is an immersion molded product that contains a water-soluble polymer having an acidic functional group and a rubber, and preferably has a film thickness of more than 0.3 mm and/or a thickness unevenness calculated as described above of 50% or less. The explanation of the manufacturing method of the present invention and the latex composition of the present invention is applicable to the immersion molded product of the present invention.
　また、上述した本発明の各実施形態について説明した各種特性（性質、構造、機能等）は、本発明を特定するにあたり、どのように組み合わせられてもよい。すなわち、本発明には、本明細書に記載される組み合わせ可能な各構成要件のあらゆる組み合わせからなる主題が全て包含される。 Furthermore, the various characteristics (properties, structures, functions, etc.) described for each embodiment of the present invention above may be combined in any way to specify the present invention. In other words, the present invention includes all subject matter consisting of all combinations of each of the combinable constituent elements described in this specification.
　以下、例を示して本発明の実施形態をより具体的に説明するが、本発明の実施形態は下記の例に限定されるものではない。なお、以下特に断らない限り、質量部はゴムラテックス中の固形分（すなわちゴム；より具体的にはクロロスルホン化ポリエチレン、水素化ニトリルゴム、クロロプレンゴム、またはスチレンブタジエンゴム）１００質量部に対する量を表す。また、凝固剤として用いた化合物は、すべて富士フイルム和光純薬社製の試薬を用いた。 The following provides a more detailed explanation of the embodiments of the present invention using examples, but the embodiments of the present invention are not limited to the following examples. Unless otherwise specified below, parts by mass represent the amount relative to 100 parts by mass of the solid content in the rubber latex (i.e. rubber; more specifically, chlorosulfonated polyethylene, hydrogenated nitrile rubber, chloroprene rubber, or styrene butadiene rubber). In addition, all of the compounds used as coagulants were reagents manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.
（実施例１）
＜ゴムラテックス組成物の調製＞
　クロロスルホン化ポリエチレンラテックス（住友精化社製、商品名「セポレックスＣＳＭ」、固形分濃度４０質量％）に、１質量部のポリアクリル酸ナトリウム（富士フイルム和光純薬社製、試薬）を加え、完全に溶解するまで攪拌してゴムラテックス組成物を得た。 Example 1
<Preparation of Rubber Latex Composition>
One part by mass of sodium polyacrylate (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd., reagent) was added to chlorosulfonated polyethylene latex (manufactured by Sumitomo Seika Chemicals, trade name "Seporex CSM", solid content concentration 40 mass%) and stirred until completely dissolved to obtain a rubber latex composition.
＜浸漬成形体の製造＞
　セラミック製の型を１５質量％の硫酸カリウムアルミニウム水溶液に５秒間浸漬し、その後、１００℃の送風乾燥機で３００秒間乾燥させた。その後、６０℃まで放冷した型を、３０℃に維持した前記ゴムラテックス組成物に３０秒間浸漬した。ラテックス組成物から引き上げた型を、１００℃の送風乾燥機で６０分間乾燥させたのち、室温まで冷却した。その後、型から皮膜を剥離し、浸漬成形体を得た。得られた浸漬成形体は以下の基準で評価した。なお、用いたセラミック製の型は２０ｃｍ×８ｃｍの長方形の薄板であり、この型の半分の長さを用いた前述の操作によって、約１０ｃｍ×８ｃｍの長方形のゴム皮膜（浸漬成形体）が２枚（型の表に１枚、裏に１枚）得られた。また、図１に示す舟の形状（縦１０ｃｍ×横１．５ｃｍ×高さ１ｃｍ）のセラミック製の型でも同様の操作を行い、複雑な形状への追随性を評価した。（舟の形状のセラミック製の型により調製した浸漬成形体は追随性評価にのみ用いた。） <Production of Dip-molded Body>
The ceramic mold was immersed in a 15% by mass aqueous solution of potassium aluminum sulfate for 5 seconds, and then dried in a 100°C air dryer for 300 seconds. The mold was then cooled to 60°C and immersed in the rubber latex composition maintained at 30°C for 30 seconds. The mold was removed from the latex composition and dried in a 100°C air dryer for 60 minutes, and then cooled to room temperature. The film was then peeled off from the mold to obtain a dip-molded body. The obtained dip-molded body was evaluated according to the following criteria. The ceramic mold used was a rectangular thin plate of 20 cm x 8 cm, and the above-mentioned operation using half the length of this mold yielded two rectangular rubber films (dip-molded bodies) of about 10 cm x 8 cm (one on the front and one on the back of the mold). The same operation was also performed on a ceramic mold in the shape of a boat (length 10 cm x width 1.5 cm x height 1 cm) shown in Figure 1, and the ability to follow a complex shape was evaluated. (The dip-molded bodies prepared using a ceramic boat-shaped mold were used only for the evaluation of conformability.)
＜皮膜の評価＞
　皮膜の膜厚および厚みのムラについては、以下のようにして評価した。 <Evaluation of the film>
The film thickness and thickness unevenness of the film were evaluated as follows.
　皮膜を長手方向に３分割したときの上部、中部、下部の範囲でそれぞれ３カ所ずつ（合計９カ所）厚みを測定して、それら９カ所の平均厚みを膜厚とした。厚みムラは、最大厚みと最小厚みとの差を前記膜厚（９カ所の平均厚み）で除した値（下記式（１）参照）で評価し、２０％未満である場合をＡ、２０％以上４０％未満である場合をＢ、４０％以上５０％未満である場合をＣ、５０％以上である場合をＤとした。
厚みムラ（％）＝（最大厚み－最小厚み）／厚みの平均値×１００　　　（Ｉ） The thickness was measured at three locations in the upper, middle, and lower areas of the film when the film was divided into three in the longitudinal direction (total of nine locations), and the average thickness of the nine locations was taken as the film thickness. The thickness unevenness was evaluated by dividing the difference between the maximum thickness and the minimum thickness by the film thickness (average thickness of the nine locations) (see formula (1) below), with A being less than 20%, B being 20% or more but less than 40%, C being 40% or more but less than 50%, and D being 50% or more.
Thickness unevenness (%) = (maximum thickness - minimum thickness) / average thickness value x 100 (I)
　また、外観を観察し、気泡や割れの有無を評価し、気泡や割れが皮膜全体にわたって見られない場合をＡ、皮膜の一部に気泡や割れが見られる場合をＢ、皮膜全体にわたって気泡や割れが見られる場合をＣとした。 The appearance was also observed and evaluated for the presence or absence of bubbles or cracks. If no bubbles or cracks were found throughout the entire film, it was rated as A, if bubbles or cracks were found in only a portion of the film, it was rated as B, and if bubbles or cracks were found throughout the entire film, it was rated as C.
＜追随性の評価＞
　得られた浸漬成形体の形状が型と同様の舟の形状であった場合は○、舟の凹部がゴムで埋まっていた場合は×と評価した。 <Evaluation of followability>
When the shape of the obtained dip-molded article was the same as that of the mold, it was rated as ◯, and when the recess of the boat was filled with rubber, it was rated as ×.
＜ラテックスの脱落の評価＞
　ラテックス組成物から薄板形状の型を引き上げた際に、ゲル化した皮膜が脱落した場合、または、ゲル化が不十分で型からラテックス組成物が垂れ落ちた場合、脱落ありと評価した。 <Evaluation of latex shedding>
When the thin plate-shaped mold was lifted from the latex composition, if the gelled film fell off, or if the latex composition dripped off the mold due to insufficient gelation, it was evaluated as "falling off."
（実施例２～４、比較例１～４）
　条件を表１の表のように変えた以外は、実施例１と同様の操作を行い、浸漬成形体を得た。 (Examples 2 to 4, Comparative Examples 1 to 4)
The same procedure as in Example 1 was carried out except that the conditions were changed as shown in Table 1, to obtain a dip-molded body.
　なお、比較例４で用いたポリビニルアルコールは、東京化成工業社製の試薬を用いた。 The polyvinyl alcohol used in Comparative Example 4 was a reagent manufactured by Tokyo Chemical Industry Co., Ltd.
　以上の結果を表１にまとめて示す。 The above results are summarized in Table 1.
Figure JPOXMLDOC01-appb-T000001
Figure JPOXMLDOC01-appb-T000001
　酸性官能基を有する水溶性ポリマーを使用し、型の温度を高くした実施例ではラテックス組成物がゲル化し、欠陥や厚みムラの少ない、厚い皮膜が得られた。一方、型の温度が高すぎると皮膜に気泡が見られ（比較例１）、型の温度が低すぎると十分にゲル化が進行せず、ラテックスの脱落が見られ（比較例２）、いずれも厚みムラの大きい皮膜しか得られなかった。さらにゲル化をさせない場合、ラテックスが垂れ、厚みムラの大きい皮膜しか得られなかった（比較例３）。また、酸性官能基を持たない水溶性ポリマーを使用した場合、凝固剤を用いてもゲル化は起こらず、ラテックスが垂れ、厚みムラの大きい皮膜しか得られなかった（比較例４）。 In the examples where a water-soluble polymer having acidic functional groups was used and the mold temperature was raised, the latex composition gelled, and a thick film with few defects and uneven thickness was obtained. On the other hand, when the mold temperature was too high, air bubbles were observed in the film (Comparative Example 1), and when the mold temperature was too low, gelation did not proceed sufficiently and latex was observed to fall off (Comparative Example 2), and in either case, only a film with large thickness unevenness was obtained. Furthermore, when gelation was not allowed, the latex sagged and only a film with large thickness unevenness was obtained (Comparative Example 3). Moreover, when a water-soluble polymer without acidic functional groups was used, gelation did not occur even with the use of a coagulant, and only a film with large thickness unevenness was obtained, with the latex sagging (Comparative Example 4).
（実施例５）
　クロロスルホン化ポリエチレンラテックス（住友精化社製、商品名「セポレックスＣＳＭ」、固形分濃度４０質量％）に、受酸剤として１５質量部のエポキシ化ポリブタジエン（日本曹達社製、商品名「ＮＩＳＳＯ―ＰＢ　ＪＰ１００」）を加え、ホモミキサー（プライミクス社製Ｔ．Ｋ．ロボミックス）を用いて、１２０００ｒｐｍで１時間混合した。その後、０．５質量部のリンゴ由来ＬＭペクチン（住友ファーマフード＆ケミカル社製、商品名「Ｈ＆Ｆペクチン　クラシックＡＢ９０２」、エステル化度４０）を加え、完全に溶解するまで攪拌した後、ジブチルジチオカルバミン酸ナトリウム水溶液（大内新興化学工業社製、商品名「ノクセラーＴＰ」）を固形分換算で３質量部を加え、さらに撹拌してゴムラテックス組成物を得た。 Example 5
Chlorosulfonated polyethylene latex (manufactured by Sumitomo Seika Chemicals, product name "Seporex CSM", solid content concentration 40 mass%) was added with 15 parts by mass of epoxidized polybutadiene (manufactured by Nippon Soda Co., Ltd., product name "NISSO-PB JP100") as an acid acceptor, and mixed for 1 hour at 12000 rpm using a homomixer (T.K. Robomix, manufactured by Primix Corporation). Then, 0.5 parts by mass of apple-derived LM pectin (manufactured by Sumitomo Pharma Food & Chemical Co., Ltd., product name "H&F Pectin Classic AB902", esterification degree 40) was added and stirred until completely dissolved, and then 3 parts by mass of sodium dibutyldithiocarbamate aqueous solution (manufactured by Ouchi Shinko Chemical Industry Co., Ltd., product name "Noccela TP") was added in terms of solid content, and further stirred to obtain a rubber latex composition.
＜浸漬成形体の製造＞
　セラミック製の型を３５質量％の硝酸カルシウム水溶液に５秒間浸漬し、その後、１６０℃の送風乾燥機で３００秒乾燥させた。その後、７４℃まで放冷した型を、２５℃に維持した前記ゴムラテックス組成物に３０秒間浸漬した。ラテックス組成物から引き上げた型を、１００℃の送風乾燥機で２０分間乾燥させたのち、さらに１６０℃で２０分間加熱た。室温まで冷却後、型から皮膜を剥離し、浸漬成形体を得た。 <Production of Dip-molded Body>
A ceramic mold was immersed in a 35% by mass aqueous solution of calcium nitrate for 5 seconds, and then dried for 300 seconds in a blast dryer at 160° C. The mold was then allowed to cool to 74° C. and immersed for 30 seconds in the rubber latex composition maintained at 25° C. The mold was removed from the latex composition, dried for 20 minutes in a blast dryer at 100° C., and then heated for another 20 minutes at 160° C. After cooling to room temperature, the film was peeled off from the mold to obtain a dip-molded product.
（実施例６～２３、比較例５～９）
　表２に記載の配合剤、配合量、浸漬方法を用いて、実施例５と同様の操作を行い、浸漬成形体を得た。なお、水溶性ポリマーは以下の市販品を用いた。
キサンタンガム：東京化成工業社製　試薬
ＣＭＣ：東京化成工業社製　試薬
κ－カラギーナン：三昌社製　商品名「ＧＥＮＵＧＥＬ　ｃａｒｒａｇｅｅｎａｎ　ｔｙｐｅ　ＪＰＥ－１２６」
ι－カラギーナン：三昌社製　商品名「ＧＥＮＵＶＩＳＣＯ　ｃａｒｒａｇｅｅｎａｎ　ｔｙｐｅ　ＰＪ－ＪＰＥ」
アルギン酸アンモニウム：富士フイルム和光純薬社製　試薬
ＨＡジェランガム：住友ファーマフード＆ケミカル社製　商品名「ケルコゲルＨＭ」
ＬＡジェランガム：住友ファーマフード＆ケミカル社製　商品名「ケルコゲル」
アルギン酸ナトリウム：東京化成工業社製　試薬 (Examples 6 to 23, Comparative Examples 5 to 9)
The same operations as in Example 5 were carried out using the ingredients, amounts of ingredients, and immersion method shown in Table 2 to obtain immersion molded bodies. The following commercially available water-soluble polymers were used.
Xanthan gum: Tokyo Chemical Industry Co., Ltd. Reagent CMC: Tokyo Chemical Industry Co., Ltd. Reagent κ-carrageenan: Sansho Co., Ltd. Product name "GENUGEL carrageenan type JPE-126"
ι-Carrageenan: Sansho Co., Ltd., product name "GENUVISCO carrageenan type PJ-JPE"
Ammonium alginate: Fujifilm Wako Pure Chemical Industries, Ltd. Reagent HA Gellan Gum: Sumitomo Pharma Food & Chemical Co., Ltd. Product name "Kelcogel HM"
LA Gellan Gum: Product name "Kelcogel" manufactured by Sumitomo Pharma Food & Chemical Co., Ltd.
Sodium alginate: Reagent manufactured by Tokyo Chemical Industry Co., Ltd.
Figure JPOXMLDOC01-appb-T000002
Figure JPOXMLDOC01-appb-T000002
　表２の通り、水溶性ポリマーとして酸性多糖類を添加したラテックスを用いた場合、種々のゲル化方法を用いることにより、きれいな厚い皮膜を得ることが出来た。一方、型の温度が適当でなかったり、ゲル化要因が欠如したりすると、きれいな厚い皮膜を得ることが難しく、またラテックスの脱落が見られた。 As shown in Table 2, when latex containing added acidic polysaccharides was used as the water-soluble polymer, a clean, thick film could be obtained by using various gelling methods. On the other hand, if the mold temperature was not appropriate or if the gelling factor was lacking, it was difficult to obtain a clean, thick film, and the latex fell off.
（実施例２４～２６）
　用いるＬＭペクチンを以下のＬＭペクチンに変えた以外は、実施例７と同様の操作を行い、浸漬成形体を得た。結果を表３にまとめた。
柑橘由来ＬＭペクチン（エステル化度９）：三昌社製　商品名「ＧＥＮＵ　ｐｅｃｔｉｎ　ｔｙｐｅ　ＬＭ－５ＣＳＪ」
柑橘由来ＬＭペクチン（エステル化度２６）：三昌社製　商品名「ＧＥＮＵ　ｐｅｃｔｉｎ　ｔｙｐｅ　ＬＭ－１０４ＡＳ－ＦＳ－Ｊ」
柑橘由来ＬＭペクチン（エステル化度３５）：富士フイルム和光純薬製　試薬 (Examples 24 to 26)
The same procedure as in Example 7 was carried out, except that the LM pectin used was changed to the following LM pectin, to obtain a dip-molded product. The results are shown in Table 3.
Citrus-derived LM pectin (esterification degree 9): Sansho Co., Ltd., product name "GENU pectin type LM-5CSJ"
Citrus-derived LM pectin (esterification degree 26): Sansho Co., Ltd., product name "GENU pectin type LM-104AS-FS-J"
Citrus-derived LM pectin (esterification degree 35): Fujifilm Wako Pure Chemical Reagent
Figure JPOXMLDOC01-appb-T000003
Figure JPOXMLDOC01-appb-T000003
　ＬＭペクチンであれば、由来やエステル化度の違いによらず、実施例５と同じ条件でゲル化させることが出来、きれいな厚い皮膜を得ることが出来た。 LM pectin could be gelled under the same conditions as in Example 5, regardless of origin or degree of esterification, and a clean, thick film could be obtained.
（実施例２７～２９）
　表４に記載のゴムラテックスの種類、配合剤、配合量を用いて、実施例１と同様の操作を行い、浸漬成形体を得た。なお、ゴムラテックスは以下の市販品を用いた。
水素化ニトリルゴムラテックス：日本ゼオン社製　商品名「Ｚｅｔｐｏｌ　２２３０ＬＸ」：表４ではＨＮＢＲと記載した。
クロロプレンゴムラテックス：東ソー社製　商品名「スカイプレン　ＬＡ－４１０」：表４ではＣＲと記載した。
スチレンブタジエンゴムラテックス：日本エイアンドエル社製　商品名「ナルスター　ＳＲ－１０４」：表４ではＳＢＲと記載した。 (Examples 27 to 29)
The same operation as in Example 1 was carried out using the types, compounding ingredients, and compounding amounts of rubber latex shown in Table 4 to obtain dip-molded bodies. The following commercially available rubber latex was used.
Hydrogenated nitrile rubber latex: Zeon Corporation, product name "Zetpol 2230LX": listed as HNBR in Table 4.
Chloroprene rubber latex: manufactured by Tosoh Corporation, product name "Skyprene LA-410": listed as CR in Table 4.
Styrene butadiene rubber latex: trade name "Nalstar SR-104" manufactured by Nippon A&L Co., Ltd.: listed as SBR in Table 4.
Figure JPOXMLDOC01-appb-T000004
Figure JPOXMLDOC01-appb-T000004
　本発明の方法はクロロスルホン化ポリエチレンラテックス以外のゴムラテックスに対しても同様の効果が得られ、いずれのゴムラテックスであってもきれいな厚い皮膜を得ることが出来た。 The method of the present invention has the same effect on rubber latex other than chlorosulfonated polyethylene latex, and a clean, thick coating can be obtained with any rubber latex.
（実施例３０）
　クロロスルホン化ポリエチレンラテックス（住友精化社製、商品名「セポレックスＣＳＭ」、固形分濃度４０質量％）に、受酸剤として１５質量部のエポキシ化ポリブタジエン（日本曹達社製、商品名「ＮＩＳＳＯ―ＰＢ　ＪＰ１００」）を加え、ホモミキサー（プライミクス社製Ｔ．Ｋ．ロボミックス）を用いて、１２０００ｒｐｍで１時間混合した。その後、２質量部のポリアクリル酸ナトリウムを加え、完全に溶解するまで攪拌した後、ジブチルジチオカルバミン酸ナトリウム水溶液（大内新興化学工業社製、商品名「ノクセラーＴＰ」）を固形分換算で３質量部を加え、さらに撹拌してゴムラテックス組成物を得た。 (Example 30)
Chlorosulfonated polyethylene latex (manufactured by Sumitomo Seika Chemicals, product name "Seporex CSM", solid content concentration 40 mass%) was added with 15 parts by mass of epoxidized polybutadiene (manufactured by Nippon Soda, product name "NISSO-PB JP100") as an acid acceptor, and mixed for 1 hour at 12000 rpm using a homomixer (T.K. Robomix, manufactured by Primix Corporation). Then, 2 parts by mass of sodium polyacrylate was added and stirred until completely dissolved, after which 3 parts by mass of sodium dibutyldithiocarbamate aqueous solution (manufactured by Ouchi Shinko Chemical Industry, product name "Noccela TP") was added in terms of solid content, and further stirred to obtain a rubber latex composition.
＜浸漬成形体の製造＞
　セラミック製の型を４０℃に加熱し、２５℃に維持した前記ゴムラテックス組成物に１０秒間浸漬し、その後、ラテックス組成物から引き上げた。ラテックス組生物が付着した型を凝固液（１５質量％の硫酸カリウムアルミニウム水溶液）に３０秒間浸漬し、その後、６０℃の温水に１０分間浸漬させ洗浄した。型を１００℃の送風乾燥機で２０分間乾燥させたのち、さらに１６０℃で２０分間加熱た。室温まで冷却後、型から皮膜を剥離し、浸漬成形体を得た。 <Production of Dip-molded Body>
A ceramic mold was heated to 40° C. and immersed in the rubber latex composition maintained at 25° C. for 10 seconds, and then removed from the latex composition. The mold with the latex composition attached was immersed in a coagulation liquid (aqueous solution of 15% by mass of potassium aluminum sulfate) for 30 seconds, and then immersed in warm water at 60° C. for 10 minutes for cleaning. The mold was dried in a 100° C. air dryer for 20 minutes, and then heated at 160° C. for 20 minutes. After cooling to room temperature, the film was peeled off from the mold to obtain a dip-molded product.
（実施例３１、３２）
　表５に記載の配合剤、配合量、凝固液を用いて、実施例４と同様の操作を行い、浸漬成形体を得た。 (Examples 31 and 32)
The same procedure as in Example 4 was carried out using the ingredients, amounts thereof, and coagulation liquid shown in Table 5 to obtain dip-molded bodies.
Figure JPOXMLDOC01-appb-T000005
Figure JPOXMLDOC01-appb-T000005
　ラテックス組成物の付着した型を凝固液に浸漬することでゲル化する方法でも、きれいな厚い皮膜が得られた。 A clean, thick coating was also obtained by immersing the mold with the latex composition in a coagulating liquid to cause it to gel.

Claims (11)

  1. 　酸性官能基を有する水溶性ポリマー及びゴムを含有するゴムラテックス組成物に、表面温度が３０℃以上１００℃未満の型を浸漬させ、型の表面にゴムラテックス組成物を付着させること、並びに、
    　型に付着したゴムラテックス組成物中の前記水溶性ポリマーをゲル化させること、
    を含む、浸漬成形体の製造方法。     A mold having a surface temperature of 30° C. or more and less than 100° C. is immersed in a rubber latex composition containing a water-soluble polymer having an acidic functional group and a rubber, thereby adhering the rubber latex composition to the surface of the mold; and
    gelling the water-soluble polymer in the rubber latex composition attached to the mold;
    A method for producing a dip-molded body comprising the steps of:
  2. 　型に付着したゴムラテックス組成物中の前記水溶性ポリマーをゲル化させることが、
    型に付着したゴムラテックス組成物中の前記水溶性ポリマーを凝固剤と接触させてゲル化させることにより実行される、請求項１に記載の方法。     Gelling the water-soluble polymer in the rubber latex composition attached to the mold,
    The method of claim 1 , carried out by contacting the water-soluble polymer in the rubber latex composition adhered to a mold with a coagulant to cause gelation.
  3. 　前記凝固剤がカルシウムイオン、マグネシウムイオン、アルミニウムイオン、亜鉛イオン、鉄イオン、銅イオン、コバルトイオン、ニッケルイオン、及びバリウムイオンからなる群より選ばれる少なくとも１種の金属イオンを含む多価イオン含有物質である、請求項２に記載の製造方法。 The method according to claim 2, wherein the coagulant is a polyvalent ion-containing substance containing at least one metal ion selected from the group consisting of calcium ions, magnesium ions, aluminum ions, zinc ions, iron ions, copper ions, cobalt ions, nickel ions, and barium ions.
  4. 　前記ゴムラテックス組成物に前記型を浸漬させる時間が１５秒以上である、請求項１～３のいずれかに記載の方法。 The method according to any one of claims 1 to 3, wherein the mold is immersed in the rubber latex composition for 15 seconds or more.
  5. 　前記ゴムラテックス組成物が、ゴム１００質量部に対して酸性官能基を有する水溶性ポリマーを０．１質量部以上含有するゴムラテックス組成物である、請求項１～３のいずれかに記載の方法。 The method according to any one of claims 1 to 3, wherein the rubber latex composition contains 0.1 parts by mass or more of a water-soluble polymer having an acidic functional group per 100 parts by mass of rubber.
  6. 　酸性官能基を有する水溶性ポリマーが酸性多糖類である、請求項１～３のいずれかに記載の方法。 The method according to any one of claims 1 to 3, wherein the water-soluble polymer having an acidic functional group is an acidic polysaccharide.
  7. 　酸性多糖類が、ＬＭペクチン、キサンタンガム、κ－カラギーナン、ι－カラギーナン、及びカルボキシメチルセルロースからなる群より選ばれる少なくとも１種である、請求項６に記載の方法。 The method according to claim 6, wherein the acidic polysaccharide is at least one selected from the group consisting of LM pectin, xanthan gum, κ-carrageenan, ι-carrageenan, and carboxymethylcellulose.
  8. 　ゴムラテックス組成物が、酸性官能基を有する水溶性ポリマー及びクロロスルホン化ポリオレフィンを含有するラテックス組成物である、請求項１～３のいずれかに記載の方法。 The method according to any one of claims 1 to 3, wherein the rubber latex composition is a latex composition containing a water-soluble polymer having an acidic functional group and a chlorosulfonated polyolefin.
  9. 　型の表面にゴムラテックス組成物を付着させることの前に、
    　さらに、凝固剤を型に付着させることを含む、請求項１～３のいずれかに記載の方法。     Prior to depositing the rubber latex composition on the surface of the mold,
    The method of any one of claims 1 to 3, further comprising depositing a coagulant on the form.
  10. 　型の表面にゴムラテックス組成物を付着させることの後に、
    　表面にゴムラテックス組成物が付着した型に、凝固剤を付着させることを含む、請求項１～３のいずれかに記載の方法。     After applying the rubber latex composition to the surface of the mold,
    The method according to any one of claims 1 to 3, comprising applying a coagulant to a mold having the rubber latex composition applied to its surface.
  11. 　酸性官能基を有する水溶性ポリマー及びゴムを含み、膜厚が０．３ｍｍより厚く、次のようにして算出される厚みムラが５０％以下である、浸漬成形体。
    ［厚みムラ算出方法］
    　浸漬成形体の皮膜を長手方向におおよそ３分割したときの上部、中部、下部の範囲でそれぞれ３カ所ずつ（合計９カ所）厚みを測定して、当該９カ所の平均厚みを膜厚とし、さらに、下記式（Ｉ）に記載のように、当該９カ所のうち最大厚みと最小厚みとの差を前記膜厚（９カ所の平均厚み）で除した値を厚みムラとする。
    厚みムラ（％）＝（最大厚み－最小厚み）／厚みの平均値×１００　　　（Ｉ）     A dip-molded article comprising a water-soluble polymer having an acidic functional group and a rubber, the thickness of the membrane being greater than 0.3 mm, and the thickness unevenness calculated as follows being 50% or less.
    [Thickness Unevenness Calculation Method]
    The coating of the immersion molded body is divided into approximately thirds in the longitudinal direction, and the thickness is measured at three locations in each of the upper, middle, and lower areas (total of nine locations). The average thickness of the nine locations is defined as the coating thickness. Furthermore, as shown in the following formula (I), the difference between the maximum and minimum thicknesses among the nine locations is divided by the coating thickness (average thickness of the nine locations) to define the thickness unevenness.
    Thickness unevenness (%) = (maximum thickness - minimum thickness) / average thickness value x 100 (I)
PCT/JP2023/033643 2022-09-26 2023-09-15 Method for producing dip-formed object, and dip-formed object WO2024070750A1 (en)

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JP2020503401A (en) * 2016-12-15 2020-01-30 シントマー スンディリアン ブルハド Curable polymer latex compositions for rubber product manufacture
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JP2009197149A (en) * 2008-02-22 2009-09-03 Nippon A&L Inc Copolymer latex for dip forming, composition for dip forming, and dip-formed product
WO2016047418A1 (en) * 2014-09-26 2016-03-31 日本ゼオン株式会社 Method for producing dip-molded article, and dip-molded article
JP2016141691A (en) * 2015-01-29 2016-08-08 日本ゼオン株式会社 Composition for dip molding and dip molded body
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