Mold-releasing agents for vulcanized rubbers, water-diluted mold-releasing agents for vulcanized rubbers, vulcanized rubbers, and manufacturing method of vulcanized rubbers

Abstract

To provide mold-releasing agents for vulcanized rubbers having excellent inserting property, mold releasability, and washability all.SOLUTION: Mold-releasing agents for vulcanized rubbers of the present invention include the following component (A) and (B): (A) adducts which comprise polyoxyalkylene adducts of amine having weight-average molecular weights of under 5,000; and (B) polyoxyalkylene adducts of alcohol.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to a release agent for vulcanized rubber, a water-diluted release agent for vulcanized rubber, vulcanized rubber, and a method for producing vulcanized rubber. [Background technology]

[0002] In the automotive and other fields, vulcanized rubber molded products such as rubber hoses are widely used. In the production of these vulcanized rubber molded products, for example, unvulcanized rubber is inserted into a mold such as a mandrel molded into a predetermined shape, vulcanized and molded, and then the vulcanized rubber molded product is removed from the mold.

[0003] In order to facilitate the insertion and removal of unvulcanized rubber from the mold, a release agent for vulcanized rubber is used. For example, Patent Document 1 proposes a compound in which ethylene oxide and propylene oxide are randomly copolymerized (average number of moles added: 30 to 180) with an aliphatic alcohol having 3 to 10 carbon atoms as a release agent for vulcanized rubber that simultaneously satisfies insertability, pullability, and washability during molding and has excellent dimensional stability of rubber products (Claim 1, paragraph 0025, etc. of the same document). Patent Document 2 also proposes a mandrel release agent for hose production that is a polyoxyethylene polyoxypropylene block copolymer having a molecular weight of 2000 to 4000, and in which the ratio of oxyethylene groups to the total molecules is less than 20 to 40% (Claim 1, paragraph 0015, etc. of the same document). Patent Document 3 also proposes the use of an AO (alkylene oxide) adduct of diamine. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2004-114472 A [Patent Document 2] JP 2004-306409 A [Patent Document 3] Japanese Patent Application Publication No. 7-292236 Summary of the Invention [Problem to be solved by the invention]

[0005] A release agent for vulcanized rubber must be easy to insert unvulcanized rubber into a molding die (e.g., a mold such as a mandrel) (insertable property), easy to remove the vulcanized rubber molded product from the mold (releasable property), and easy to remove the release agent adhering to the surface of the vulcanized rubber molded product after it has been removed (cleanable property).

[0006] The release agents for vulcanized rubber described in Patent Documents 1 to 3 exhibit their performance by blending a polymer surfactant in which an alkylene oxide is added to a polyhydric alcohol. However, the polymer surfactant becomes highly viscous at high concentrations, which may make it difficult to wash off and may damage the appearance of the vulcanized rubber. On the other hand, if the blending amount of polyhydric alcohols is reduced to ensure washability, the amount of adhesion to the vulcanized rubber may decrease, which may damage the release properties. Therefore, there is a need for a release agent for vulcanized rubber that exhibits high adhesion prevention performance and slipperiness in vulcanized rubber, has high washability, and does not damage the appearance of the product.

[0007] Therefore, an object of the present invention is to provide a release agent for vulcanized rubber, which is excellent in all of insertability, releasability and washability, a water-diluted release agent for vulcanized rubber, vulcanized rubber and a method for producing vulcanized rubber. [Means for solving the problem]

[0008] In order to achieve the above object, the release agent for vulcanized rubber of the present invention is characterized by comprising the following components (A) and (B): (A) A polyoxyalkylene adduct of an amine having a weight average molecular weight of less than 5000. (B) Polyoxyalkylene adduct of alcohol

[0009] The aqueous dilution of the release agent for vulcanized rubber of the present invention is obtained by diluting the release agent for vulcanized rubber of the present invention with water.

[0010] The first vulcanized rubber of the present invention is characterized in that it is obtained by adhering the release agent for vulcanized rubber of the present invention or the water-diluted release agent for vulcanized rubber of the present invention to the interface between unvulcanized rubber and a molding die, and then vulcanizing the rubber.

[0011] The second vulcanized rubber of the present invention is characterized in that the component (A) and the component (B) in the release agent for vulcanized rubber of the present invention are adhered to the surface.

[0012] The method for producing vulcanized rubber of the present invention is characterized by comprising a vulcanization step of vulcanizing the unvulcanized rubber in a state in which the release agent for vulcanized rubber of the present invention or the aqueous diluted solution of the release agent for vulcanized rubber of the present invention is attached to the interface between the unvulcanized rubber and a mold. Effect of the Invention

[0013] According to the present invention, it is possible to provide a release agent for vulcanized rubber, which is excellent in all of insertability, releasability and washability, a water-diluted release agent for vulcanized rubber, vulcanized rubber, and a method for producing vulcanized rubber. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to the following description.

[0015] [1. Release agents for vulcanized rubber] As described above, the release agent for vulcanized rubber of the present invention is characterized by containing the following components (A) and (B). (A) A polyoxyalkylene adduct of an amine having a weight average molecular weight of less than 5000. (B) Polyoxyalkylene adduct of alcohol

[0016] [1-1. Polyoxyalkylene adducts] The component (A) and the component (B) of the release agent for vulcanized rubber of the present invention are polyoxyalkylene adducts as described above. In the present invention, the polyoxyalkylene of the polyoxyalkylene adduct is not particularly limited, but for example, the polyoxyalkylene may be a polymer of an oxyalkylene group having 2 to 4 carbon atoms. In addition, the polyoxyalkylene may or may not contain an oxyethylene group, for example, and may or may not contain an oxypropylene group. In addition, in the present invention, the polyoxyalkylene may be a polymer of only one type of oxyalkylene group, or may be a copolymer of multiple types of oxyalkylene groups. In addition, in the present invention, chain-like groups such as alkyl groups and alkylene groups may be linear or branched, unless otherwise specified. In addition, in the present invention, when the polymer (for example, polyoxyalkylene) is a copolymer, it may be a block copolymer or a random copolymer, unless otherwise specified.

[0017] In the present invention, the oxyethylene group (hereinafter sometimes referred to as "EO") is an atomic group represented by the following chemical formula (1). [ka]

[0018] In the present invention, the oxypropylene group (hereinafter sometimes referred to as "PO") is an atomic group represented by the following chemical formula (2). [ka]

[0019] In the component (A) and the component (B) of the release agent for vulcanized rubber of the present invention, the polyoxyalkylene may be, for example, composed of only EO or only PO. However, from the viewpoint of compatibility between the releasability and washability of the release agent for vulcanized rubber, it is preferable to contain both EO and PO, and it is more preferable to be composed of only EO and PO. In the polyoxyalkylene, the number of EO is preferably 20% or more, 30% or more, or 40% or more of the total number of oxyalkylene groups from the viewpoint of washability of the release agent for vulcanized rubber. In addition, the number of EO is preferably 80% or less, 70% or less, or 60% or less of the total number of oxyalkylene groups from the viewpoint of releasability (lubricity) of the release agent for vulcanized rubber. In the polyoxyalkylene, the number of PO is preferably 20% or more, 30% or more, or 40% or more of the total number of oxyalkylene groups from the viewpoint of releasability (lubricity) of the release agent for vulcanized rubber. From the viewpoint of the washability of the release agent for vulcanized rubber, the number of PO's is preferably 80% or less, 70% or less, or 60% or less of the total number of oxyalkylene groups.

[0020] In the release agent for vulcanized rubber of the present invention, the mass ratio ((A) / (B)) obtained by dividing the mass of the component (A) by the mass of the component (B) is not particularly limited, but is preferably 0.05 to 30. From the viewpoint of washability, it is preferable that the mass ratio (A) / (B) is not too small. From the viewpoint of releasability, it is preferable that the mass ratio (A) / (B) is not too large. The mass ratio (A) / (B) may be, for example, 0.05 or more, 0.1 or more, or 0.2 or more, and may be, for example, 15 or less, 10 or less, or 5 or less.

[0021] [1-2. Polyoxyalkylene adduct of amine (A)] The component (A) (polyoxyalkylene adduct of amine) in the release agent for vulcanized rubber of the present invention is not particularly limited, and may be, for example, a polyoxyalkylene derivative represented by the following chemical formula (I).

[0022] [ka]

[0023] In the above chemical formula (I), each R is an arbitrary atom or atomic group, for example, a hydrogen atom, an alkyl group (for example, an alkyl group having 1 to 18 carbon atoms), or a group represented by the following chemical formula (I-2), and may be the same or different, provided that at least one R is a group represented by the following chemical formula (I-2).

[0024] [ka]

[0025] In the above chemical formula (I-2), R 41 is an alkylene group (e.g., an alkylene group having 2 to 4 carbon atoms), and n 41 is a positive integer and represents the degree of polymerization, and each R 41 In the above chemical formula (I), -R 41 The polymerization unit (oxyalkylene) represented by -O- may be, for example, EO, PO, or EO and PO. 41 For example, may be 1 or more and may be 100 or less.

[0026] The polyoxyalkylene adduct of amine may be, for example, a polyoxyalkylene adduct of polyamine (diamine, triamine, etc.). The polyoxyalkylene adduct of diamine may be, for example, a polyoxyalkylene derivative represented by the following chemical formula (II).

[0027] [ka]

[0028] In the above chemical formula (II), R 50is an alkylene group (e.g., an alkyl group having 1 to 18 carbon atoms), and each R is an arbitrary atom or atomic group, for example, a hydrogen atom, an alkyl group (e.g., an alkyl group having 1 to 18 carbon atoms), or a group represented by the following chemical formula (II-2), which may be the same or different, provided that at least one R is a group represented by the following chemical formula (II-2).

[0029] [ka]

[0030] In the above chemical formula (II-2), R 51 is an alkylene group (e.g., an alkylene group having 2 to 4 carbon atoms), and n 51 is a positive integer and represents the degree of polymerization, and each R 51 In the above chemical formula (I), -R 51 The polymerization unit (oxyalkylene) represented by -O- may be, for example, EO, PO, or EO and PO. 51 For example, may be 1 or more and may be 100 or less.

[0031] The polyoxyalkylene derivative represented by the above chemical formula (II) may be, for example, a polyoxyalkylene derivative represented by the following chemical formula (II-3). [ka]

[0032] In the chemical formula (II-3), A is 2 to 6, and a1, b1, c1, d1, m1, a2, b2, c2, d2, m2, a3, b3, c3, d3, m3, a4, b4, c4, d4, and m4 are each a positive integer.

[0033] In the release agent for vulcanized rubber of the present invention, the component (A) of the polyoxyalkylene adduct of amine may be used alone or in combination of two or more kinds.

[0034] In the release agent for vulcanized rubber of the present invention, the polyoxyalkylene adduct of amine, which is the component (A), may be, for example, an ethylenediamine polyoxyalkylene adduct.

[0035] In the release agent for vulcanized rubber of the present invention, the polyoxyalkylene adduct of amine, which is the component (A), has a weight average molecular weight of less than 5000 as described above. If the weight average molecular weight of the component (A) is 5000 or more, there is a problem that the cleaning property of the release agent is reduced, so the weight average molecular weight of the component (A) needs to be less than 5000. The weight average molecular weight of the component (A) may be, for example, 4500 or less, 4000 or less, or 3500 or less. The lower limit of the weight average molecular weight of the component (A) is not particularly limited, but may be, for example, 500 or more, 1000 or more, 1500 or more, or 2000 or more. From the viewpoint of releasability, it is preferable that the weight average molecular weight of the component (A) is not too small.

[0036] In the release agent for vulcanized rubber of the present invention, the content of the polyoxyalkylene adduct of amine, which is the component (A), is not particularly limited, but may be, for example, 0.5 to 95% by mass based on the total mass of the components other than water in the release agent for vulcanized rubber. The content of the component (A) may be, for example, 93% by mass or less, 90% by mass or less, 88% by mass or less, or 85% by mass or less based on the total mass of the components other than water in the release agent for vulcanized rubber, and may be, for example, 1.0% by mass or more, 5.0% by mass or more, 10.0% by mass or more, or 20.0% by mass or more. From the viewpoint of washability, it is preferable that the content of the component (A) is not too low. From the viewpoint of releasability, it is preferable that the content of the component (A) is not too high.

[0037] In the release agent for vulcanized rubber of the present invention, the content of the polyoxyalkylene adduct of amine, which is the component (A), is not particularly limited, and may be, for example, 0.5 to 80% by mass relative to the total mass of the release agent for vulcanized rubber. The content of the component (A) may be, for example, 70% by mass or less, 50% by mass or less, 40% by mass or less, or 30% by mass or less relative to the total mass of the release agent for vulcanized rubber, and may be, for example, 1.0% by mass or more, 2.0% by mass or more, 3.0% by mass or more, or 5.0% by mass or more.

[0038] In the present invention, the method for measuring the weight-average molecular weight of a substance is not particularly limited. For example, the weight-average molecular weight of the substance, including but not limited to the component (A), can be measured by GPC (gel permeation chromatography) under the following analysis conditions. (Analysis conditions) Equipment: Waters e2695 Detector: Refractive index detector Waters 2414 Columns: A total of three columns, Waters HSPgel MB-H, RT2.0, and RT4.0, were connected in series. Solvent: Tetrahydrofuran Flow rate: 0.3mL / min Temperature: 40℃

[0039] In the oxyalkylene adduct of amine, which is the component (A), the oxyalkylene group may contain, for example, an oxyethylene group, as described above. In this case, the content of the oxyethylene group is not particularly limited, but, for example, the content of the oxyethylene group in the oxyalkylene is preferably 5 to 50 mass% when the mass of the entire oxyalkylene group is 100 mass%. The content of the oxyethylene group in the oxyalkylene in the component (A) may be, for example, 45 mass% or less, 40 mass% or less, 35 mass% or less, 30 mass% or less, or 25 mass% or less when the mass of the entire oxyalkylene group is 100 mass%, and may be, for example, 8 mass% or more, 10 mass% or more, 12 mass% or more, or 15 mass% or more. From the viewpoint of cleaning property, it is preferable that the content of the oxyethylene group is not too low. From the viewpoint of releasability, it is preferable that the content of the oxyethylene group is not too high.

[0040] [1-3. Polyoxyalkylene adducts of alcohols (B)] The component (B) (polyoxyalkylene adduct of alcohol) in the release agent for vulcanized rubber of the present invention is not particularly limited, and may be, for example, a polyoxyalkylene adduct of a monohydric alcohol (monool) or a polyoxyalkylene adduct of a polyhydric alcohol (e.g., diol, triol, etc.). Examples of the monohydric alcohol (monool) include methanol, ethanol, propanol, butanol, 2-ethylhexanol, nonanol, lauryl alcohol, and tridecanol. Examples of the polyhydric alcohol include ethylene glycol, glycerin, trimethylolpropane, pentaerythritol, and sorbitol.

[0041] The polyoxyalkylene adduct of the monohydric alcohol (monool) may be, for example, a polyoxyalkylene derivative represented by the following chemical formula (III).

[0042] [ka]

[0043] In the above chemical formula (III), R 1 is an alkyl group (e.g., an alkyl group having 1 to 18 carbon atoms), and R 11 is an alkylene group (e.g., an alkylene group having 2 to 4 carbon atoms), and n 11 is a positive integer and represents the degree of polymerization, and each R 11 In the above chemical formula (III), -R 11 The polymerization unit (oxyalkylene) represented by -O- may be, for example, EO, PO, or EO and PO. 11 For example, may be 1 or more and 500 or less.

[0044] Among the polyhydric alcohols, the polyoxyalkylene adduct of a dihydric alcohol (diol) may be, for example, a polyoxyalkylene derivative represented by the following chemical formula (IV).

[0045] [ka]

[0046] In the above chemical formula (IV), R 2 is an alkylene group (e.g., an alkyl group having 1 to 4 carbon atoms), and R 21 is an alkylene group (e.g., an alkylene group having 2 to 4 carbon atoms), and n 21 is a positive integer and represents the degree of polymerization, and each R 21 may be the same or different. 22 is an alkylene group (e.g., an alkylene group having 2 to 4 carbon atoms), and n 22 is a positive integer and represents the degree of polymerization, and each R 22 In the above chemical formula (IV), -R 21 -O- and OR 22 The polymerization unit (oxyalkylene) represented by - may be, for example, EO, PO, or EO and PO. 21 and n 22may be, for example, 1 or more and 400 or less.

[0047] Among the polyhydric alcohols, the polyoxyalkylene adduct of a trihydric alcohol (triol) may be, for example, a polyoxyalkylene derivative represented by the following chemical formula (V).

[0048] [ka]

[0049] In the above chemical formula (V), R 3 is a saturated hydrocarbon group (e.g., a saturated hydrocarbon group having 1 to 4 carbon atoms), and R 31 is an alkylene group (e.g., an alkylene group having 2 to 4 carbon atoms), and n 31 is a positive integer and represents the degree of polymerization, and each R 31 may be the same or different. 32 is an alkylene group (e.g., an alkylene group having 2 to 4 carbon atoms), and n 32 is a positive integer and represents the degree of polymerization, and each R 32 may be the same or different. 33 is an alkylene group (e.g., an alkylene group having 2 to 4 carbon atoms), and n 33 is a positive integer and represents the degree of polymerization, and each R 33 In the above chemical formula (IV), -R 31 -O-, -OR 32 - and OR 33 The polymerization unit (oxyalkylene) represented by - may be, for example, EO, PO, or EO and PO. 31 , n 32 and n 33 may be, for example, 1 or more and 300 or less.

[0050] Among the polyoxyalkylene adducts of alcohols, examples of the polyoxyalkylene adducts of monools include Adeka Carpol MH-1000. Examples of the polyoxyalkylene adducts of diols include Adeka Carpol PH-2000, Adeka Carpol PH-800, Braunon P-178, Epan U-108, Epan 785, and Leocon 2105E. Examples of the polyoxyalkylene adducts of triols include Adeka Carpol GH-10, Adeka Carpol GH-5, and Leocon CW-200. All of the names containing "Adeka Carpol" above are trade names of ADEKA Corporation. All of the names containing "Braunon" above are trade names of Aoki Oil & Fat Industries Co., Ltd., all of the names containing "Epan" above are trade names of Daiichi Kogyo Seiyaku Co., Ltd., and all of the names containing "Leocon" above are trade names of Lion Specialty Chemicals Co., Ltd.

[0051] In the release agent for vulcanized rubber of the present invention, the polyoxyalkylene adduct of alcohol, which is the component (B), may be used alone or in combination of two or more kinds.

[0052] In the release agent for vulcanized rubber of the present invention, the weight average molecular weight of the polyoxyalkylene adduct of alcohol, which is the component (B), is not particularly limited, but may be, for example, 30,000 or less, 20,000 or less, 10,000 or less, 8,000 or less, or 6,000 or less. From the viewpoint of cleaning properties, it is preferable that the weight average molecular weight of the component (B) is not too large. The lower limit of the weight average molecular weight of the component (B) is not particularly limited, but may be, for example, 500 or more, 1,000 or more, 1,500 or more, or 2,000 or more. From the viewpoint of releasability, it is preferable that the weight average molecular weight of the component (B) is not too small.

[0053] In the release agent for vulcanized rubber of the present invention, the content of the polyoxyalkylene adduct of alcohol, which is the component (B), is not particularly limited, and may be, for example, 0.5 to 95% by mass based on the total mass of the components other than water in the release agent for vulcanized rubber. The content of the component (A) may be, for example, 93% by mass or less, 90% by mass or less, 88% by mass or less, or 85% by mass or less based on the total mass of the components other than water in the release agent for vulcanized rubber, and may be, for example, 1.0% by mass or more, 5.0% by mass or more, 10.0% by mass or more, or 20.0% by mass or more. From the viewpoint of washability, it is preferable that the content of the component (B) is not too low. From the viewpoint of releasability, it is preferable that the content of the component (B) is not too high.

[0054] In the release agent for vulcanized rubber of the present invention, the content of the polyoxyalkylene adduct of alcohol, which is the component (B), is not particularly limited, and may be, for example, 0.5 to 80 mass% based on the total mass of the release agent for vulcanized rubber. The content of the component (A) may be, for example, 40 mass% or less, 30 mass% or less, 20 mass% or less, or 10 mass% or less based on the total mass of the release agent for vulcanized rubber, and may be, for example, 0.8 mass% or more, 1.0 mass% or more, 1.2 mass% or more, or 1.5 mass% or more.

[0055] In the polyoxyalkylene adduct of alcohol, which is the component (B), the oxyalkylene group may contain, for example, an oxyethylene group, as described above. In this case, the content of the oxyethylene group is not particularly limited, but, for example, the content of the oxyethylene group in the oxyalkylene is preferably 5 to 50 mass% when the mass of the entire oxyalkylene group is 100 mass%. The content of the oxyethylene group in the oxyalkylene in the component (B) may be, for example, 45 mass% or less, 40 mass% or less, 35 mass% or less, or 30 mass% or less when the mass of the entire oxyalkylene group is 100 mass%, and may be, for example, 8 mass% or more, 10 mass% or more, 13 mass% or more, or 15 mass% or more. From the viewpoint of cleaning property, it is preferable that the content of the oxyethylene group is not too low. From the viewpoint of releasability, it is preferable that the content of the oxyethylene group is not too high.

[0056] [1-4.Optional components] The release agent for vulcanized rubber of the present invention may or may not contain any optional components other than the component (A) and the component (B).

[0057] [1-4-1. Dilution solvent] The release agent for vulcanized rubber of the present invention may or may not contain a dilution solvent. The dilution solvent is not particularly limited, but is preferably water from the viewpoints of cost, ease of handling, solvent crack resistance of the release agent, and the like. The water is not particularly limited, but may be, for example, tap water, ion-exchanged water, and the like. The content of the water is not particularly limited, but may be, for example, 98% by mass or less, 95% by mass or less, 93% by mass or less, or 90% by mass or less, and may be, for example, 5% by mass or more, 10% by mass or more, 15% by mass or more, 20% by mass or more, or 40% by mass or more, with respect to the total mass of the release agent for vulcanized rubber. From the viewpoint of washability, it is preferable that the content of water is not too low. From the viewpoint of releasability, it is preferable that the content of water is not too high.

[0058] The release agent for vulcanized rubber of the present invention may or may not contain a dilution solvent other than water as the dilution solvent. As the dilution solvent other than water, for example, alcohol such as methanol, ethanol, isopropyl alcohol, etc. can be used alone or in combination with water.

[0059] [1-4-2.Nonionic surfactants] The optional components may or may not contain a nonionic surfactant. For example, it is preferable to further include a nonionic surfactant as a release component in addition to the components (A) and (B), since the washability is further improved. The reason for this is not entirely clear, but it is believed that the addition of a nonionic surfactant appropriately reduces the viscosity of the release agent after the dilution solvent evaporates in the high-temperature vulcanization process, allowing it to be washed in a short time (high washability).

[0060] The nonionic surfactant is not particularly limited, but may be the same as the nonionic surfactant contained as a release component in a general release agent for vulcanized rubber. More specifically, the nonionic surfactant may be the same as the nonionic surfactant contained as a release component in a general release agent for mandrels (release agent for vulcanized rubber). The nonionic surfactant may be, for example, glycerin fatty acid ester, sorbitan fatty acid ester, sucrose fatty acid ester, polyoxyethylene polyoxypropylene glycol, polyoxyethylene alkylphenyl ether, etc. Among these, the nonionic surfactant represented by the following chemical formula (3) is preferred. RO-(AO) n -R (3)

[0061] In the chemical formula (3), each R is a hydrogen atom, an aliphatic hydrocarbon group, or an acyl group, and may be the same or different. However, at least one of the Rs is an aliphatic hydrocarbon group or an acyl group. The aliphatic hydrocarbon group may be, for example, an aliphatic hydrocarbon group having 8 to 18 carbon atoms. The acyl group may be, for example, an acyl group having 8 to 18 carbon atoms. The aliphatic hydrocarbon group may be linear or branched, and may be either saturated or unsaturated. The acyl group may be linear or branched, and may be either saturated or unsaturated. The number of carbon atoms in R is preferably 12 to 16, more preferably 12 to 14, from the viewpoint of excellent dispersibility of the component (A). AO represents an oxyalkylene group having 2 to 4 carbon atoms, and n represents the average number of moles of AO added. n is preferably 1 to 30, and more preferably 3 to 25. Specifically, from the viewpoint of preventing a decrease in surface activity and a decrease in dispersibility of component (A), n is preferably 1 or more (i.e., not 0). Moreover, from the viewpoint of preventing a decrease in adhesiveness due to excessively high hydrophilicity, n preferably does not exceed 30, and more preferably does not exceed 25.

[0062] In the release agent for vulcanized rubber of the present invention, the nonionic surfactant may be used alone or in combination of two or more kinds.

[0063] In the release agent for vulcanized rubber of the present invention, the weight average molecular weight of the nonionic surfactant is not particularly limited, but may be, for example, less than 5,000. The weight average molecular weight of the nonionic surfactant may be, for example, 4,500 or less, 4,000 or less, or 3,500 or less. From the viewpoint of cleaning properties, it is preferable that the weight average molecular weight of the nonionic surfactant is not too large. The lower limit of the weight average molecular weight of the nonionic surfactant is not particularly limited, but may be, for example, 500 or more, 1000 or more, 1500 or more, or 2000 or more. From the viewpoint of releasability, it is preferable that the weight average molecular weight of the nonionic surfactant is not too small.

[0064] In the release agent for vulcanized rubber of the present invention, the blending amount (content) of the nonionic surfactant is preferably not too high from the viewpoint of achieving both releasability and washability at a low concentration. If the blending amount (content) of the nonionic surfactant is too high, the release agent is difficult to retain at the interface between the rubber and the mold, and the release property may be reduced. When the release agent for vulcanized rubber of the present invention contains the nonionic surfactant, the blending amount (content) may be, for example, 20% by mass or less, 15% by mass or less, 10% by mass or less, 5% by mass or less, or 2% by mass or less, for example, 0.01% by mass or more, 0.05% by mass or more, 0.1% by mass or more, 0.5% by mass or more, or 1% by mass or more, based on the total mass of the components other than water in the release agent for vulcanized rubber.

[0065] [1-4-3. Viscosity modifier] The release agent for vulcanized rubber of the present invention may or may not contain a viscosity modifier as the optional component. For example, by adding a thickener as a viscosity modifier, the viscosity of the release agent for vulcanized rubber can be appropriately increased, and the release property can be further improved. The thickener is not particularly limited, but examples thereof include mono- or di-fatty acid esters of polyethylene glycol, xanthan gum, tamarind gum, propylene glycol, carboxymethylcellulose (CMC), sodium alginate, polyvinyl alcohol, acrylic polymers, etc.

[0066] In the release agent for vulcanized rubber of the present invention, the viscosity modifier may be used alone or in combination of two or more kinds.

[0067] In the release agent for vulcanized rubber of the present invention, the blending amount (content) of the viscosity modifier is preferably 1 to 15% by weight, more preferably 3 to 10% by weight, based on the total weight of the release agent for vulcanized rubber. Also, the blending amount (content) of the viscosity modifier is preferably 10 to 25% by weight, based on the total weight of the components excluding the dilution solvent (e.g. water) from the release agent for vulcanized rubber.

[0068] [1-4-4. Solubilizing agents] The release agent for vulcanized rubber of the present invention may contain, for example, a solubilizing agent. The solubilizing agent is not particularly limited, but examples thereof include cationic surfactants, anionic surfactants, and nonionic surfactants. The nonionic surfactant may contain, for example, the nonionic surfactant described above.

[0069] Examples of the cationic surfactant include alkylamine salts and quaternary ammonium salts. Examples of the nonionic surfactant include alkyl ether EOPO adducts, alkylamine EOPO adducts, polyoxyalkylene alkyl ether type nonionic surfactants. Examples of the nonionic surfactant include the nonionic surfactants exemplified above as the nonionic surfactants. Examples of the anionic surfactant include the following (1) to (4). (1) Carboxylic acid type anionic surfactants, such as higher fatty acid salts, alkyl ether carboxylates, polyoxyalkylene ether carboxylates, alkyl (or alkenyl) amide ether carboxylates, and acylamino carboxylates. (2) Sulfate-type anionic surfactants, such as higher alcohol sulfates, polyoxyalkylene higher alcohol sulfates, alkyl phenyl ether sulfates, polyoxyalkylene alkyl phenyl ether sulfates, and glycerin fatty acid ester monosulfates. (3) Sulfonic acid type anionic surfactants such as alkanesulfonates, α-olefinsulfonates, linear alkylbenzenesulfonates, α-sulfofatty acid ester salts, and dialkylsulfosuccinates. (4) Phosphate ester type anionic surfactants, such as alkyl phosphate ester salts, polyoxyalkylene alkyl phosphate ester salts, polyoxyalkylene alkylphenyl phosphate ester salts, and glycerin fatty acid ester monophosphate ester salts.

[0070] The counter ion of the anionic surfactant is not particularly limited, but is preferably an alkali metal such as sodium or potassium, or an alkanolamine such as monoethanolamine or diethanolamine. These may be used alone or in combination of two or more.

[0071] As the anionic surfactant, a dialkyl sulfosuccinate salt (alkyl sulfosuccinate salt) is preferred, and dioctyl sulfosuccinate sodium salt is more preferred, since it gives an antiadhesive agent suspension that has superior wettability with the surface of unvulcanized rubber.

[0072] In the release agent for vulcanized rubber of the present invention, the solubilizing agent may be used alone or in combination of two or more kinds.

[0073] In the release agent for vulcanized rubber of the present invention, the blending amount (content) of the solubilizing agent is preferably 0.3 to 8% by weight, more preferably 0.3 to 6% by weight, based on the total weight of the release agent for vulcanized rubber. The blending amount (content) of the solubilizing agent is preferably 3 to 20% by weight, more preferably 3 to 15% by weight, based on the total weight of the components excluding the dilution solvent (e.g. water) from the release agent for vulcanized rubber.

[0074] [1-4-5. Antibacterial agents, etc.] The release agent for vulcanized rubber of the present invention may or may not contain, as the optional components, known release components such as antibacterial agents, nonionic surfactants, anionic surfactants, silicones, oils (mineral oils, vegetable oils, mineral oils, etc.), preservatives, rust inhibitors, etc. The antibacterial agents are not particularly limited, but examples thereof include cyclic nitrogen-based antibacterial agents, etc.

[0075] [2. Method for producing release agent for vulcanized rubber] The method for producing the release agent for vulcanized rubber of the present invention is not particularly limited, but for example, each component may simply be mixed. For example, from the viewpoint of ease of handling, each component may be dissolved or dispersed in a dilution solvent to prepare the release agent for vulcanized rubber of the present invention. In this case, the weight of the components other than the dilution solvent may be, for example, 10 to 80% by weight of the entire release agent for vulcanized rubber. The dilution solvent is not particularly limited, but as described above, water is preferred from the viewpoints of cost, ease of handling, and solvent crack resistance of the release agent. The water is not particularly limited, but examples thereof include tap water and ion-exchanged water, as described above. In addition to water, for example, alcohols such as methanol, ethanol, and isopropyl alcohol can be used alone or in combination with water.

[0076] When dissolving or dispersing each of the components in the diluent solvent, heating, stirring, etc. may be performed as necessary. The heating temperature may be, for example, 20 to 90° C. The heating time may be, for example, 0.2 to 5 hours, etc.

[0077] [3. Methods of using release agents for vulcanized rubber, methods of manufacturing vulcanized rubber, etc.] The method of using the release agent for vulcanized rubber of the present invention is not particularly limited, and for example, it can be used in the same manner as the method of using a general release agent for vulcanized rubber. Specifically, for example, as described above, the release agent for vulcanized rubber of the present invention or the water dilution of the present invention is attached to the interface between the unvulcanized rubber and the mold, and the unvulcanized rubber is vulcanized. As described above, the vulcanized rubber can be produced by the method of producing vulcanized rubber of the present invention, which includes this vulcanization step.

[0078] The release agent for vulcanized rubber of the present invention may be used as it is without dilution, or may be diluted with water before use (before being attached to the interface between the unvulcanized rubber and the mold) to form the water-diluted solution of the present invention. The weight of the components other than water in the water-diluted solution of the present invention may be, for example, 7 to 36% by weight, or 10 to 30% by weight of the entire water-diluted solution of the present invention.

[0079] The mold may be, for example, a molding mold. The mold may be, but is not particularly limited to, a metal mold, for example, a mandrel, etc. The vulcanized rubber may be, for example, a vulcanized rubber molded product. The vulcanized rubber molded product may be, but is not particularly limited to, for example, a rubber hose, etc. The method of attaching the release agent for vulcanized rubber of the present invention or the water-diluted solution of the present invention to the interface between the unvulcanized rubber and the mold is not particularly limited, and a general method or a method similar thereto can be used. Specifically, for example, a method of immersing the tip of the unvulcanized rubber (for example, an unvulcanized rubber hose) in the release agent, a method of applying the release agent to the interface in advance with a brush or spray, etc., etc. are mentioned. At this time, for example, the release agent for vulcanized rubber of the present invention or the water-diluted solution of the present invention is attached to one or both of the unvulcanized rubber and the mold. For example, when the mold is a mandrel and the unvulcanized rubber is an unvulcanized rubber hose, the release agent for vulcanized rubber of the present invention or the water-diluted solution of the present invention may be attached to one or both of the outer surface of the mandrel and the inner surface of the hose by, for example, coating or immersion.

[0080] The vulcanization process for vulcanizing the unvulcanized rubber may be, for example, a vulcanization molding process for vulcanizing and molding the unvulcanized rubber. The vulcanization process is not particularly limited, and can be carried out in the same manner as a general vulcanization process or vulcanization molding process for unvulcanized rubber. Specifically, for example, steam vulcanization, hot air vulcanization, etc. can be used. Note that a method of vulcanizing a mandrel with an unvulcanized hose inserted therein by placing it in a vulcanizing can (a device that vulcanizes an unvulcanized hose by filling the device with steam or hot air) is called "steam vulcanization" and a method of vulcanizing with hot air is called "hot air vulcanization".

[0081] The type of vulcanized rubber that can be produced by the method for producing vulcanized rubber of the present invention is not particularly limited, but examples thereof include rubbers that can be vulcanized and molded, such as natural rubber, styrene-butadiene rubber (SBR), acrylonitrile-butadiene rubber (NBR), butyl rubber (IIR), ethylene-propylene-diene copolymer rubber (EPDM), blend polymer of NBR and polyvinyl chloride (NBR / PVC), etc. In addition, the vulcanized rubber that can be produced by the method for producing vulcanized rubber of the present invention is also not particularly limited, but examples thereof include rubber molded products such as rubber hoses and rubber seals.

[0082] The release agent for vulcanized rubber of the present invention, for example, has excellent insertability, which can prevent deformation and wrinkling when unvulcanized rubber (e.g., unvulcanized rubber hose) is inserted into a mold (e.g., mandrel). In addition, for example, the release coating has high slipperiness and excellent releasability, which provides excellent workability when pulling out the rubber after vulcanization. In addition, for example, the release agent has excellent cleanability, which can be easily washed off in a cleaning process, which provides an excellent appearance for the vulcanized rubber product.

[0083] For example, by covering the interface between the hose and the mandrel with the release agent for vulcanized rubber of the present invention and preventing contact between the mandrel and the rubber hose, it is possible to prevent adhesion during vulcanization and provide slippage when inserting and removing the hose, thereby ensuring workability in the rubber hose manufacturing process and preventing defects such as deformation of the finished rubber hose.

[0084] In the present invention, the component (A) (a polyoxyalkylene adduct of an amine having a weight-average molecular weight of less than 5000) and the component (B) (a polyoxyalkylene adduct of an alcohol) are used in combination. As mentioned above, the polyoxyalkylene adduct of an alcohol has a problem of becoming a highly viscous body at a high concentration. In contrast, the release agent for vulcanized rubber of the present invention can maintain a low viscosity even at a high concentration by using a polyoxyalkylene adduct of an amine having a low molecular weight as the component (A). The release agent for vulcanized rubber of the present invention can, for example, exhibit high adhesion prevention performance and slip performance while also exhibiting high washability that allows easy removal from vulcanized rubber products, and can also not impair the appearance of the vulcanized rubber products. The release agent for vulcanized rubber of the present invention can be easily washed while maintaining, for example, adhesion prevention and insertability between the hole and the mandrel, and therefore can manufacture and provide a high-quality rubber hose without impairing the appearance of the product. Furthermore, as described above, the release agent for vulcanized rubber of the present invention is not limited to rubber hoses and mandrels, but may be applied to any rubber product and mold. EXAMPLES

[0085] Next, examples of the present invention will be described, but the present invention is not limited to the following examples.

[0086] [Examples 1 to 11 and Comparative Examples 1 to 4] The release agents for vulcanized rubber of Examples 1 to 11 (Table 1) and Comparative Examples 1 to 4 (Table 2) were produced by mixing the components shown in Tables 1 and 2 in the mass ratios shown in the following Tables 1 and 2. The numerical values ​​of each component in Tables 1 and 2 are the content (mass%) of each component when the total mass of the release agent for vulcanized rubber is taken as 100 mass%. In Tables 1 and 2, (A) represents the component (A) of the present invention, and (B) represents the component (B) of the present invention.

[0087] [Method for measuring weight average molecular weight] In the following Tables 1 and 2, the weight average molecular weight was measured by GPC (gel permeation chromatography) under the following analytical conditions. (Analysis conditions) Equipment: Waters e2695 Detector: Refractive index detector Waters 2414 Columns: A total of three columns, Waters HSPgel MB-H, RT2.0, and RT4.0, were connected in series. Solvent: Tetrahydrofuran Flow rate: 0.3mL / min Temperature: 40℃

[0088] [Method for evaluating the characteristics of release agents for vulcanized rubber] The properties (insertion property, releasability, and washability) of each release agent for vulcanized rubber produced in the Examples and Comparative Examples were measured and evaluated by the following methods. The evaluation results are shown in Tables 1 and 2 below.

[0089] (1) Evaluation method for insertability and releasability An unvulcanized rubber hose made of acrylic rubber soaked in a release agent was inserted into a molded hose mandrel coated with the release agent. The release agent was used as is without diluting it with water. The ease of insertion was evaluated on a 5-point scale from 1 to 5 according to the following criteria. 5: Easy to insert without resistance 4: There is slight resistance when inserting, but it can be inserted easily 3: There is some resistance when inserting, but it can be inserted 2: There is a lot of resistance when inserting, but it can be inserted 1: There is resistance when inserting and it cannot be inserted

[0090] Next, the unvulcanized rubber hose inserted into the mandrel was heated at 150°C for 30 minutes to perform a vulcanization treatment to obtain a vulcanized rubber hose. After that, the vulcanized rubber hose was pulled out from the mandrel. The workability during this pulling out (removing) was regarded as demoldability, and was evaluated on a 5-point scale from 5 to 1, similar to the insertion ability, according to the following criteria. 5: Easy to remove without resistance 4: There is a slight resistance when removing from the mold, but it comes out easily 3: There is some resistance when removing the mold, but it comes out easily 2: There is a lot of resistance when removing the mold, but it comes out 1: There is resistance when releasing and it does not come out

[0091] (2) Method for evaluating cleaning performance The vulcanized rubber hose obtained in the above evaluation of insertion property and releasability was immersed in water at 40°C for 2 minutes and then taken out. Thereafter, the surface of the vulcanized rubber hose was visually observed and evaluated on a three-level scale of ○, △, and × according to the following criteria. ○: After immersion for 2 minutes, no release agent remains on the surface of the vulcanized rubber hose. △: After immersion for 2 minutes, a small amount of release agent remains on the surface of the vulcanized rubber hose. ×: A large amount of release agent remains on the surface of the vulcanized rubber hose even after immersion for 2 minutes.

[0092] [Table 1]

[0093] The following components were used as the components (raw materials) in Table 1. The same applies to Table 2 below. The "EO ratio" below indicates the mass ratio of oxyethylene groups when the total oxyalkylene groups are taken as 100 mass%. Raw materials used Component (A) A-1: Ethylenediamine polyoxyalkylene adduct (weight average molecular weight 4650, EO ratio 40%), synthetic product. A-2: Ethylenediamine polyoxyalkylene adduct (weight average molecular weight 3500, EO ratio 20%), synthetic product. A-3: Ethylenediamine polyoxyalkylene adduct (weight average molecular weight 3100, EO ratio 10%), synthetic product. A-4: Propanediamine polyoxyalkylene adduct (weight average molecular weight 3200, EO ratio 10%), synthetic product. A-5: Pentanediamine polyoxyalkylene adduct (weight average molecular weight 3100, EO ratio 10%), synthetic product. (B) Component B-1: Polyoxyalkylene alcohol (weight average molecular weight 4800, EO ratio 50%), synthetic product. B-2: Polyoxyalkylene glycol (weight average molecular weight 3100, EO ratio 10%), synthetic product. B-3: Polyoxyalkylene glycol (weight average molecular weight 2600, EO ratio 20%), synthetic product. B-4: Polyoxyalkylene glycerol (weight average molecular weight 2600, EO ratio 50%), synthetic product. Other Ingredients PEG distearate, synthetic product. Antibacterial agent: Cyclic nitrogen-based antibacterial agent.

[0094] [Table 2]

[0095] As shown in Table 1, the release agents for vulcanized rubber of Examples 1 to 11, which contain the components (A) and (B) of the present invention, were excellent in all of the insertability, releasability, and washability. In contrast, the release agents for vulcanized rubber of Comparative Examples 1 and 2, which contain only the component (A) of the present invention but do not contain the component (B), were excellent in washability but inferior in insertability and releasability to the Examples. On the other hand, the release agents for vulcanized rubber of Comparative Examples 3 and 4, which contain only the component (B) of the present invention but do not contain the component (A), were excellent in insertability and releasability but inferior in washability to the Examples.

[0096] <Additional Notes> A part or all of the above-described embodiments and examples may be described as follows, but is not limited to the following. (Appendix 1) A release agent for vulcanized rubber, comprising the following components (A) and (B): (A) A polyoxyalkylene adduct of an amine having a weight average molecular weight of less than 5000. (B) Polyoxyalkylene adduct of alcohol (Appendix 2) 2. The release agent for vulcanized rubber according to claim 1, wherein the content of the polyoxyalkylene adduct of amine, which is the component (A), is 0.5 to 95 mass % based on the total mass of the components other than water in the release agent for vulcanized rubber. (Appendix 3) 3. The release agent for vulcanized rubber according to claim 1 or 2, wherein the content of the polyoxyalkylene adduct of amine, which is the component (A), is 0.5 to 80% by mass based on the total mass of the release agent for vulcanized rubber. (Appendix 4) The release agent for vulcanized rubber according to any one of Appendices 1 to 3, wherein the content of the polyoxyalkylene adduct of alcohol, which is the component (B), is 0.5 to 95 mass % based on the total mass of the components other than water in the release agent for vulcanized rubber. (Appendix 5) 5. The release agent for vulcanized rubber according to any one of claims 1 to 4, wherein the content of the polyoxyalkylene adduct of alcohol, which is the component (B), is 0.5 to 80 mass % based on the total mass of the release agent for vulcanized rubber. (Appendix 6) 6. The release agent for vulcanized rubber according to any one of claims 1 to 5, wherein a mass ratio ((A) / (B)) obtained by dividing the mass of the component (A) by the mass of the component (B) is 0.05 to 30. (Appendix 7) 7. The release agent for vulcanized rubber according to any one of claims 1 to 6, wherein in the oxyalkylene adduct of alcohol which is component (B), the content of oxyethylene groups in the oxyalkylene is 5 to 50 mass%, with the mass of all oxyalkylene groups being 100 mass%. (Appendix 8) 8. The release agent for vulcanized rubber according to any one of claims 1 to 7, wherein in the amine oxyalkylene adduct which is the component (A), the content of oxyethylene groups in the oxyalkylene is 5 to 50 mass%, with the mass of all oxyalkylene groups being 100 mass%. (Appendix 9) 9. The release agent for vulcanized rubber according to any one of claims 1 to 8, wherein the oxyalkylene adduct of an amine, which is component (A), is an ethylenediamine polyoxyalkylene adduct. (Appendix 10) 10. A water-diluted release agent for vulcanized rubber, obtained by diluting the release agent for vulcanized rubber according to any one of claims 1 to 9 with water. (Appendix 11) A vulcanized rubber, characterized in that the vulcanized rubber release agent according to any one of claims 1 to 9 or the water-diluted release agent according to claim 10 is applied to the interface between unvulcanized rubber and a mold, and the vulcanized rubber is vulcanized. (Appendix 12) 12. The vulcanized rubber according to claim 11, wherein the mold is a molding mold. (Appendix 13) 13. The vulcanized rubber according to claim 12, wherein the mold is a mandrel. (Appendix 14) 10. A vulcanized rubber, comprising the release agent for vulcanized rubber according to any one of claims 1 to 9, and the component (A) and the component (B) adhered to a surface of the vulcanized rubber. (Appendix 15) The vulcanized rubber according to any one of appendixes 11 to 14, wherein the vulcanized rubber is a rubber hose. (Appendix 16) A method for producing vulcanized rubber, comprising a vulcanization step of vulcanizing unvulcanized rubber in a state in which the release agent for vulcanized rubber according to any one of claims 1 to 9 or the water-diluted release agent for vulcanized rubber according to claim 10 is attached to an interface between the unvulcanized rubber and a mold. (Appendix 17) The method of claim 16, wherein the mold is a molding mold. (Appendix 18) The method of claim 17, wherein the mold is a mandrel. (Appendix 19) The method according to any one of appendixes 16 to 18, wherein the vulcanized rubber is a rubber hose.

Claims

1. It contains the following components (A) and (B), In the polyoxyalkylene adduct of alcohol which is the following component (B), with the total mass of the oxyalkylene groups being 100% by mass, the content of oxyethylene groups in the oxyalkylene is 5 to 50% by mass, and it is a mold release agent for vulcanized rubber characterized by this. (A) A polyoxyalkylene adduct of an amine, and the adduct has a weight average molecular weight of less than 5000 (B) A polyoxyalkylene adduct of alcohol

2. The mold release agent for vulcanized rubber according to Claim 1, wherein the mass ratio ((A) / (B)) obtained by dividing the mass of the component (A) by the mass of the component (B) is 0.05 to 30.

3. The mold release agent for vulcanized rubber according to Claim 1, wherein the component (B) is a polyoxyalkylene adduct of a polyhydric alcohol, and its weight average molecular weight is 1000 or more and 30000 or less.

4. In the oxyalkylene adduct of amine which is the component (A), with the total mass of the oxyalkylene groups being 100% by mass, the content of oxyethylene groups in the oxyalkylene is 5 to 50% by mass, and it is the mold release agent for vulcanized rubber according to Claim 1.

5. The mold release agent for vulcanized rubber according to Claim 1, wherein the oxyalkylene adduct of amine which is the component (A) is an ethylenediamine polyoxyalkylene adduct.

6. A water-diluted solution of the mold release agent for vulcanized rubber, which is obtained by diluting the mold release agent for vulcanized rubber according to Claim 1 with water.

7. A vulcanized rubber characterized by adhering the mold release agent for vulcanized rubber according to Claim 1 or the water-diluted solution of the mold release agent for vulcanized rubber according to Claim 6 to the interface between the unvulcanized rubber and the mold and then vulcanizing.

8. The vulcanized rubber according to Claim 7, wherein the mold is a molding mold.

9. The vulcanized rubber according to Claim 7, wherein the vulcanized rubber is a rubber hose. Claim 10 A method for producing vulcanized rubber, comprising a vulcanization step of vulcanizing the unvulcanized rubber in a state where the mold release agent for vulcanized rubber according to claim 1 or the aqueous dilution of the mold release agent for vulcanized rubber according to claim 6 is adhered to the interface between the unvulcanized rubber and the mold.