JPWO2010113907A1 - Composite molded body, method for producing the same, and use of the composite molded body - Google Patents

Abstract

A member comprising a polyurethane alone or a polyurethane composition mainly comprising polyurethane and a member comprising silicone alone or a silicone composition mainly comprising silicone, wherein the polyurethane comprises a polymer polyol, an organic polyisocyanate and a chain extender. In which the polymer polyol mainly contains a polyester polyol, and the aromatic dicarboxylic acid unit and the aromatic occupy the total of all dicarboxylic acid units and all hydroxycarboxylic acid units constituting the polyester polyol. A composite molded article excellent in adhesiveness, comprising a polyurethane having a total proportion of hydroxycarboxylic acid units of 30 to 100 mol%, and a method for producing the same.

Description

  The present invention relates to a composite molded body useful as a material constituting a keypad used for a communication terminal such as a mobile phone, various instruments, a keyboard for personal computer input, an operation part of a remote controller, and the like, and a method for manufacturing the same.

  In recent years, a key manufactured by bonding a key top (button key) to a keypad obtained from a keypad film made of a resin film such as thermoplastic polyurethane, polyethylene terephthalate, polyester elastomer, etc. Sheets are widely used in operation units such as communication terminals such as mobile phones, various instruments, keyboards for PC input, and remote controls, and several techniques related to such key sheets are known (for example, patents). Reference 1 and 2 etc.). Among the materials of the keypad film constituting the keypad, thermoplastic polyurethane is particularly suitable because it has high durability in addition to moderate soft feeling and excellent cushioning properties. Several techniques related to keypad films made of thermoplastic polyurethane are also known.

  For example, a thermoplastic polyurethane synthesized by using, as a synthesis component, an isocyanate and a polyol selected from hexamethylene diisocyanate or hydrogenated diphenylmethane diisocyanate as a keypad surface material to be laminated on silicone rubber or the like as a keypad There has been proposed a method of forming a surface material made of polyurethane which is excellent in soft touch, does not cause yellowing, has high water resistance and heat resistance, and has little deterioration in physical properties by being composed of a resin (see Patent Document 3).

  Resin pellets obtained by reacting an organic diisocyanate mainly composed of hexamethylene diisocyanate, a polymer polyol mainly composed of polycarbonate diol, and a chain extender mainly composed of an aliphatic diol having 2 to 10 carbon atoms. A polyurethane resin keypad obtained by thermoforming a thermoplastic polyurethane resin sheet obtained by melt-molding is excellent in secondary moldability, oleic acid resistance, discoloration resistance, transparency, printability, etc. It is known (see Patent Document 4).

  By the way, when manufacturing a keypad or a key sheet using a keypad film made of a resin such as thermoplastic polyurethane, a silicone adhesive or printing ink is applied to solidify or fix it. Or laminated with a layer made of silicone resin. However, since the surface activity of normal thermoplastic polyurethane keypad film is insufficient, surface activation treatment such as primer treatment, corona discharge treatment, plasma treatment, ozone treatment, flame treatment, etc. must be performed in advance. There is a bad work efficiency.

  For example, a thermoplastic resin such as polycarbonate, polypropylene, polybutylene terephthalate, etc., is injected into the mold cavity as a primary injection using an injection molding machine, for example, as a technology for integrally molding a thermoplastic resin and a silicone resin without surface activation treatment. After molding, the addition-curable silicone rubber composition is subjected to secondary injection molding on the thermoplastic resin layer formed in the cavity, and at the same time, the silicone rubber composition is cured at a temperature not lower than the melting point and lower than the melting point of the thermoplastic resin. A method of manufacturing a composite molded body in which a silicone rubber layer and a thermoplastic resin layer are laminated and integrated is known (see Patent Document 5).

  However, even if this method is applied to the production of a composite molded body of a thermoplastic polyurethane and a silicone resin, a composite molded body in which the thermoplastic polyurethane layer and the silicone resin layer are well bonded cannot be obtained.

JP 2004-327307 A JP 2004-111258 A JP 2005-25960 A International Publication No. 2004/106401 Pamphlet JP-A-8-174604

  SUMMARY OF THE INVENTION The present invention solves the above problems, and an object of the present invention is to provide a composite molded body in which a polyurethane-containing member and a silicone-containing member are sufficiently bonded to each other without performing surface activation treatment, and a method for producing the same. And providing a keypad and a key sheet using the composite molded body.

  As a result of various studies conducted by the present inventors to achieve the above object, a polyester polyol containing an aromatic dicarboxylic acid and an aromatic hydroxycarboxylic acid as a polycarboxylic acid component as a polymer polyol in the production of polyurethane. The polyurethane is excellent in adhesiveness with silicone, and the polyurethane composition containing a specific amount of carboxylate salt is excellent in adhesiveness with silicone. The present invention was completed by overlapping.

That is, the present invention
[1] A first member that is made of polyurethane alone or a member made of a polyurethane composition mainly containing polyurethane, and a second member that is made of silicone alone or made of a silicone composition mainly containing silicone. A composite molded body having a member,
The polyurethane of the first member is a polyurethane obtained by reacting a polymer polyol, an organic polyisocyanate and a chain extender, and the polymer polyol mainly contains a polyester polyol, and all dicarboxylic acids constituting the polyester polyol A composite molded article comprising a polyurethane having a total proportion of aromatic dicarboxylic acid units and aromatic hydroxycarboxylic acid units in the total of the units and all hydroxycarboxylic acid units of 30 to 100 mol%,
[2] In the above, the first member has a third member which is a member made of a polyurethane composition containing 0.01 to 2 parts by mass of a carboxylate with respect to 100 parts by mass of polyurethane. The composite molded article according to [1],
[3] The polyurethane is a polyurethane obtained by reacting a polymer polyol, an organic polyisocyanate and a chain extender, wherein the polymer polyol mainly contains a polyester polyol, and all dicarboxylic acid units constituting the polyester polyol And the composite molded article according to the above [2], wherein the ratio of the total of aromatic dicarboxylic acid units and aromatic hydroxycarboxylic acid units in the total of all hydroxycarboxylic acid units is polyurethane of 30 to 100 mol%,
[4] The above, wherein the ratio of the total of aromatic dicarboxylic acid units and aromatic hydroxycarboxylic acid units to the total of all dicarboxylic acid units and all hydroxycarboxylic acid units constituting the polyester polyol is 30 to 95 mol%. 1] or a composite molded article according to [3],
[5] The composite molded body according to any one of [1] to [4], wherein the first member or the third member has a thickness of 10 to 3000 μm.
[6] A first member which is a member made of polyurethane alone or a polyurethane composition mainly containing polyurethane, and a second member which is made of silicone alone or a silicone composition mainly containing silicone. A method for producing a composite molded body having a member,
The polyurethane of the first member is a polyurethane obtained by reacting a polymer polyol, an organic polyisocyanate and a chain extender,
The polymer polyol mainly contains a polyester polyol, and the ratio of the total of aromatic dicarboxylic acid units and aromatic hydroxycarboxylic acid units in the total of all dicarboxylic acid units and all hydroxycarboxylic acid units constituting the polyester polyol is 30 to 30%. 100 mol%,
Forming a second member by curing the curable silicone composition on the first member;
[7] A method for producing a composite molded body having a third member which is a member made of a polyurethane composition containing 0.01 to 2 parts by mass of a carboxylate salt with respect to 100 parts by mass of polyurethane instead of the first member. And
The method for producing a composite molded article according to the above [6], wherein the second member is formed by curing the curable silicone composition on the third member,
[8] The polyurethane is a polyurethane obtained by reacting a polymer polyol, an organic polyisocyanate, and a chain extender, and an aromatic occupying the total of all dicarboxylic acid units and all hydroxycarboxylic acid units constituting the polyester polyol. The method for producing a composite molded article according to the above [7], comprising a polyurethane having a total ratio of the aromatic dicarboxylic acid unit and the aromatic hydroxycarboxylic acid unit of 30 to 100 mol%,
[9] The above, wherein the ratio of the total of aromatic dicarboxylic acid units and aromatic hydroxycarboxylic acid units to the total of all dicarboxylic acid units and all hydroxycarboxylic acid units constituting the polyester polyol is 30 to 95 mol%. 6] or the production method according to [8],
[10] The manufacturing method according to any one of [6] to [9], wherein the first member or the third member has a thickness of 10 to 3000 μm.
[11] A keypad formed from the composite molded body according to any one of [1] to [5], and [12] a key sheet having at least the keypad and keytop according to [11]. .

According to the present invention, it is possible to obtain a composite molded body in which a member containing polyurethane and a member containing silicone are sufficiently bonded without performing surface activation treatment.
Further, according to the present invention, a composite molded body in which a member containing polyurethane and a member containing silicone are sufficiently bonded can be efficiently produced.
The composite molded body is particularly useful when manufacturing a keypad or a key sheet.

Hereinafter, the present invention will be described in detail.
The present invention includes the composite molded body of the first aspect described below and the composite molded body of the second aspect described below.

[Composite Molded Body of First Aspect]
The composite molded body of the first aspect of the present invention is a composite molded body having the following first member and second member.
First member: a member made of polyurethane alone or made of a polyurethane composition mainly containing polyurethane (hereinafter, the member may be abbreviated as “polyurethane-based member”).
Second member: a member made of silicone alone or a silicone composition mainly containing silicone (hereinafter, the member may be abbreviated as “silicone-based member”).

  In the composite molded body of the first aspect, the polyurethane-based member and the silicone-based member are in contact.

  The polyurethane is a polyurethane obtained by reacting a polymer polyol, an organic polyisocyanate and a chain extender.

  The polymer polyol mainly includes a polyester polyol. And the ratio of the sum total of the aromatic dicarboxylic acid unit and the aromatic hydroxycarboxylic acid unit in the total of all the dicarboxylic acid units and all the hydroxycarboxylic acid units constituting the polyester polyol is in the range of 30 to 100 mol%, Preferably it exists in the range of 40-100 mol%, More preferably, it exists in the range of 50-100 mol%, More preferably, it exists in the range of 70-100 mol%. The ratio of the aromatic dicarboxylic acid unit and the aromatic hydroxycarboxylic acid unit in the total of all dicarboxylic acid units and all hydroxycarboxylic acid units constituting the polyester polyol is within the above range, so that the adhesiveness to the silicone-based member is increased. A polyurethane-based member with improved can be obtained.

  Further, the ratio of the total of the aromatic dicarboxylic acid unit and the aromatic hydroxycarboxylic acid unit in the total of all the dicarboxylic acid units and all the hydroxycarboxylic acid units constituting the polyester polyol is in the range of 30 to 100 mol%, By being in the range of 30 to 95 mol% (preferably in the range of 30 to 90 mol%, more preferably in the range of 30 to 85 mol%, particularly preferably in the range of 40 to 70 mol%), The polyurethane member has a good balance between the adhesiveness with the silicone-based member and the excellent flexibility.

  As the above-mentioned polyester polyol, a polyol component and a dicarboxylic acid component such as a dicarboxylic acid or an ester-forming derivative thereof (ester (lower alkyl ester, aryl ester, carbonate ester, etc.), acid anhydride, etc.) are directly esterified. Or polyester polyol obtained by transesterification; polymerizing hydroxycarboxylic acid components such as hydroxycarboxylic acid or ester-forming derivatives thereof (esters (lower alkyl esters, aryl esters, carbonates, etc.), acid anhydrides, lactones, etc.) Examples thereof include polyester polyols obtained by polymerizing polyester polyols obtained by polymerizing the above polyol component, dicarboxylic acid component and hydroxycarboxylic acid component. Further, as a component for producing a polyester polyol, a compound having a trifunctional or higher functional group (that is, a compound having three or more functional groups) (for example, three or more carboxy groups such as trimellitic acid and pyromellitic acid) A polyester polyol having 2 or more hydroxyl groups per molecule can also be produced by using a small amount of a polycarboxylic acid having a hydroxyl group or a polyol having 3 or more hydroxyl groups per molecule described later. In the polyester polyol used in the present invention, the ratio of the dicarboxylic acid unit in the total of the dicarboxylic acid unit and the hydroxycarboxylic acid unit is within the range of 50 to 100 mol% from the viewpoint of availability of raw materials. Preferably, it is in the range of 80 to 100 mol%, more preferably in the range of 95 to 100 mol%, and particularly preferably 100 mol%.

  As the dicarboxylic acid component and / or hydroxycarboxylic acid component used in producing the polyester polyol, aromatic dicarboxylic acid and / or aromatic hydroxycarboxylic acid, or ester-forming derivatives thereof in a desired ratio. By using, the ratio of the sum total of the aromatic dicarboxylic acid unit and the aromatic hydroxycarboxylic acid unit which occupies for the sum total of all the dicarboxylic acid units and all the hydroxycarboxylic acid units which comprise a polyester polyol can be made into the said range.

  Examples of the aromatic dicarboxylic acid include terephthalic acid, isophthalic acid, orthophthalic acid, and naphthalenedicarboxylic acid. The aromatic dicarboxylic acid may be used alone or in combination of two or more. May be. Among these, the aromatic dicarboxylic acid is preferably terephthalic acid and / or isophthalic acid. Examples of the aromatic hydroxycarboxylic acid include 4-hydroxymethylbenzoic acid, 4- (2-hydroxyethyl) benzoic acid, 4- (2-hydroxyethoxy) benzoic acid, and the like. The group hydroxycarboxylic acid may be used alone or in combination of two or more.

  The polyester polyol contains a non-aromatic dicarboxylic acid unit and / or a non-aromatic hydroxycarboxylic acid unit as long as the total ratio of the aromatic dicarboxylic acid unit and the aromatic hydroxycarboxylic acid unit falls within the above range. Also good. As the dicarboxylic acid component that gives the non-aromatic dicarboxylic acid unit, dicarboxylic acid components generally used in the production of polyesters can be used. For example, succinic acid, glutaric acid, adipic acid, pimelic acid , Suberic acid, azelaic acid, sebacic acid, dodecanedioic acid, methylsuccinic acid, 2-methylglutaric acid, 3-methylglutaric acid, trimethyladipic acid, 2-methyloctanedioic acid, 3,8-dimethyldecanedioic acid, 3 Aliphatic dicarboxylic acids having 4 to 12 carbon atoms such as 1,7-dimethyldecanedioic acid; cycloaliphatic dicarboxylic acids such as cyclohexanedicarboxylic acid, dimer acid and hydrogenated dimer acid; or ester-forming derivatives thereof. Can do. These dicarboxylic acid components may be used alone or in combination of two or more. Among them, the dicarboxylic acid component that gives a non-aromatic dicarboxylic acid unit is preferably an aliphatic dicarboxylic acid having 4 to 12 carbon atoms, more preferably an aliphatic dicarboxylic acid having 6 to 12 carbon atoms. More preferably, it is at least one selected from the group consisting of acids, azelaic acid and sebacic acid.

  In addition, as the hydroxycarboxylic acid component that gives the above-mentioned non-aromatic hydroxycarboxylic acid unit, a hydroxycarboxylic acid component generally used in the production of polyesters can be used, for example, 6-hydroxyhexanoic acid, C4-C12 aliphatic hydroxycarboxylic acids such as 5-hydroxy-3-methylpentanoic acid; or ester-forming derivatives thereof (ε-caprolactone, β-methyl-δ-valerolactone, etc.). it can. These hydroxycarboxylic acid components may be used alone or in combination of two or more.

  On the other hand, as the above-mentioned polyol component used in producing a polyester polyol, a polyol component generally used in the production of polyester can be used, for example, ethylene glycol, diethylene glycol, triethylene glycol, propylene. Glycol, 1,3-propanediol, 2-methyl-1,3-propanediol, 2,2-diethyl-1,3-propanediol, 1,3-butanediol, 1,4-butanediol, 2-methyl -1,4-butanediol, neopentyl glycol, 1,5-pentanediol, 3-methyl-1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol 2-methyl-1,8-octanediol, 2,7-di Carbon number of til-1,8-octanediol, 1,9-nonanediol, 2-methyl-1,9-nonanediol, 2,8-dimethyl-1,9-nonanediol, 1,10-decanediol, etc. 2-15 aliphatic diols; 1,4-cyclohexanediol, cyclohexanedimethanol (1,4-cyclohexanedimethanol, etc.), cyclooctanedimethanol, dimethylcyclooctanedimethanol, etc .; 1,4- Diols having two hydroxyl groups per molecule such as aromatic dihydric alcohols such as bis (β-hydroxyethoxy) benzene, trimethylolpropane, trimethylolethane, glycerin, 1,2,6-hexanetriol, pentaerythritol, Polyols having 3 or more hydroxyl groups per molecule such as diglycerin And so on.

  In addition to the above, as the polyol component used in producing the polyester polyol, polyether polyol, polycarbonate polyol, polyolefin polyol, conjugated diene polymer polyol which may be hydrogenated, castor oil polyol, Polymer polyols such as vinyl polymer-based polyols can also be used. The number average molecular weight of the polymer polyol used as the polyol component used when producing the polyester polyol is preferably in the range of 500 to 8,000, and in the range of 600 to 5,000. It is more preferable that it is in the range of 800 to 3,500. In addition, the said number average molecular weight is a number average molecular weight computed based on the hydroxyl value measured based on JISK-1557.

  In producing the polyester polyol, these polyol components may be used alone or in combination of two or more. Among these, the polyol component is preferably an aliphatic diol having 2 to 15 carbon atoms, more preferably an aliphatic diol having 4 to 10 carbon atoms, 1,4-butanediol, 3-methyl-1 More preferably, it is at least one selected from the group consisting of 1,5-pentanediol, 1,6-hexanediol and 1,8-octanediol.

  The polyester polyol used in the production of the above polyurethane is an aromatic dicarboxylic acid unit and an aromatic hydroxycarboxylic acid unit as long as the total ratio of the aromatic dicarboxylic acid unit and the aromatic hydroxycarboxylic acid unit falls within the above range. The polyester polyol which does not contain any of these may be included. In the case of using such a polyester polyol in combination, the above-mentioned ratio of the total of the aromatic dicarboxylic acid unit and the aromatic hydroxycarboxylic acid unit does not include any of the aromatic dicarboxylic acid unit and the aromatic hydroxycarboxylic acid unit. It means the proportion of the total of aromatic dicarboxylic acid units and aromatic hydroxycarboxylic acid units in the total of all dicarboxylic acid units and all hydroxycarboxylic acid units constituting the polyester polyol including polyester polyol.

  Moreover, although the said polymer polyol used for manufacture of a polyurethane may contain only polyester polyol, it may contain other polymer polyol other than that other than polyester polyol. As such other polymer polyol, any polymer polyol conventionally used in the production of polyurethane can be used. For example, polyether polyol, polycarbonate polyol, polyolefin-based polyol, hydrogenated Examples thereof include good conjugated diene polymer-based polyols, castor oil-based polyols, vinyl polymer-based polyols, and the like. These other polymer polyols may be used alone or in combination of two or more. Among these, polyether polyol and / or polyolefin-based polyol are preferable.

  As a content rate of the polyester polyol in the polymer polyol used for the production of polyurethane, the adhesive strength between the polyurethane-based member containing the obtained polyurethane and the silicone-based member can be improved. It is preferably within the range, and more preferably within the range of 80 to 100% by mass.

  The number average molecular weight of the polymer polyol used for the production of polyurethane is preferably in the range of 500 to 8,000, more preferably in the range of 600 to 5,000, and 800 to 3, More preferably, it is in the range of 500, even more preferably 850 to 1200, particularly preferably 900 to 1100, and most preferably 1000. By using a polymer polyol having a number average molecular weight in the above range, mechanical properties such as non-adhesiveness, melt moldability, abrasion resistance, and tensile strength at break, flexibility, flexibility, and low residual strain A polyurethane excellent in various properties such as can be obtained. In this specification, the number average molecular weight of the polymer polyol used for the production of polyurethane is a number average molecular weight calculated based on the hydroxyl value measured according to JIS K-1557.

  In addition, as the number of hydroxyl groups per molecule in the polymer polyol used for the production of polyurethane, polyurethane having excellent melt moldability, non-adhesiveness, abrasion resistance, mechanical properties and the like can be obtained. It is preferably within the range of 0 to 2.1, and more preferably within the range of 2.0 to 2.07.

  As said organic polyisocyanate used for manufacture of a polyurethane, any organic polyisocyanate conventionally used for manufacture of a polyurethane can be used. Examples of the organic polyisocyanate include 4,4′-diphenylmethane diisocyanate (MDI), tolylene diisocyanate, phenylene diisocyanate, xylylene diisocyanate, 1,5-naphthylene diisocyanate, 3,3′-dichloro-4,4 ′. -Aromatic diisocyanates such as diphenylmethane diisocyanate; aliphatic or alicyclic diisocyanates such as hexamethylene diisocyanate, isophorone diisocyanate, 4,4'-dicyclohexylmethane diisocyanate, and hydrogenated xylylene diisocyanate. These organic polyisocyanates may be used alone or in combination of two or more. Among them, the organic polyisocyanate mainly contains 4,4′-diphenylmethane diisocyanate because a polyurethane that is non-adhesive, excellent in melt moldability, excellent in mechanical properties, and excellent in heat resistance can be obtained (preferably 50 mol% or more, more preferably 80 mol% or more, further preferably 95 mol% or more, particularly preferably 100 mol%).

  As the chain extender used in the production of polyurethane, a low molecular weight compound having two or more active hydrogen atoms and a molecular weight of 400 or less can be used. Specifically, ethylene glycol, propylene glycol, 1, Diols such as 4-butanediol (BD), 1,6-hexanediol, 1,4-bis (β-hydroxyethoxy) benzene, 1,4-cyclohexanediol, bis (β-hydroxyethyl) terephthalate, xylylene glycol Diamines such as hydrazine, ethylenediamine, propylenediamine, xylylenediamine, isophoronediamine, piperazine or derivatives thereof, phenylenediamine, tolylenediamine, xylenediamine, adipic acid dihydrazide, isophthalic acid dihydrazide; aminoethyl alcohol And amino alcohols such as aminopropyl alcohol. These chain extenders may be used individually by 1 type, or may use 2 or more types together. Among these, since a polyurethane that is non-adhesive, excellent in melt moldability, excellent in mechanical properties, and excellent in heat resistance is obtained, the chain extender is mainly an aliphatic diol having 2 to 10 carbon atoms. (Preferably 50 mol% or more, more preferably 80 mol% or more, further preferably 95 mol% or more, particularly preferably 100 mol%), and mainly contains 1,4-butanediol (preferably 50 mol% or more). More preferably, it contains at least 80 mol%, more preferably at least 80 mol%, even more preferably at least 95 mol%, particularly preferably 100 mol%).

  In the production of polyurethane by reacting the above-mentioned polymer polyol, organic polyisocyanate and chain extender, the mixing ratio of each component is appropriately determined in consideration of the hardness, mechanical performance, etc. to be imparted to the target polyurethane. Although it is determined, it is preferable to use each component in such a ratio that the molar ratio of active hydrogen atoms: isocyanate groups present in the reaction system is in the range of 1: 0.9 to 1.3. It is more preferable to use each component at a ratio of 9 to 1.1. By using each component in the above proportion, a polyurethane excellent in mechanical properties represented by abrasion resistance, tensile breaking strength, tensile breaking elongation, and the like can be obtained.

  The production method of the polyurethane is not particularly limited, and any of known urethanation reaction techniques may be employed using a polymer polyol, an organic polyisocyanate and a chain extender, and a prepolymer method or a one-shot method Any of these can be employed. Among these, it is preferable to perform melt polymerization substantially in the absence of a solvent, and it is more preferable to employ a continuous melt polymerization method using a multi-screw extruder. The polymerization temperature for melt polymerization is preferably in the range of 180 to 280 ° C.

  In producing polyurethane by reacting the above-described polymer polyol, organic polyisocyanate and chain extender, a urethanization reaction catalyst may be used. The type of the urethanization reaction catalyst is not particularly limited, and any urethanization reaction catalyst conventionally used in the production of polyurethane can be used. Examples of the urethanization reaction catalyst include at least one compound selected from organic tin compounds, organic zinc compounds, organic bismuth compounds, organic titanium compounds, organic zirconium compounds, and amine compounds. Can do. A urethanization reaction catalyst may be used individually by 1 type, or may use 2 or more types together.

  The content of nitrogen atoms derived from isocyanate groups in the polyurethane is preferably in the range of 1.5 to 6% by mass, more preferably in the range of 2 to 5% by mass, and 2.5 to 5%. The content is more preferably in the range of mass%, particularly preferably 3 to 5 mass%, particularly preferably 4 to 5 mass%. Polyurethanes having a content of nitrogen atoms derived from isocyanate groups within the above range are excellent in adhesiveness to silicone, and polyurethane-based members containing them are represented by wear resistance, tensile breaking strength, tensile breaking elongation, etc. It has excellent properties such as mechanical properties.

  The composite molded body of the first aspect is produced by curing the curable silicone composition on the polyurethane-based member. Thereby, even if it does not perform a surface activation process, the composite molded object with which the polyurethane-type member (1st member) and the silicone-type member (2nd member) fully adhere | attached can be obtained.

  The melt viscosity of the polyurethane is preferably in the range of 1,000 to 4,000 Pa · s, and in the range of 1,500 to 3,000 Pa · s, as measured by the method described in the Examples. Is more preferable. The polyurethane having such a melt viscosity is advantageous in that a thermoplastic polyurethane having excellent melt moldability, excellent mechanical properties represented by tensile stress and tear strength, and excellent heat resistance can be obtained.

  The production method of the polyurethane-based member is not particularly limited, and may be produced by employing any of the above-described molding techniques using the above-described polyurethane or polyurethane composition, for example, injection molding, extrusion molding, Various shapes (for example, sheets, films, plates, tubular bodies, rod-shaped bodies, hollow molded bodies, various containers, various block-shaped moldings by any molding method such as inflation molding, blow molding, calendar molding, press molding, casting, etc. Body, various molds, etc.). Among the molding methods described above, it is preferable to employ injection molding, extrusion molding or inflation molding, and it is more preferable to employ extrusion molding or inflation molding using a single screw type extruder. In this case, the cylinder temperature of the single screw extruder is preferably in the range of 180 to 230 ° C.

Examples of the curable silicone composition for forming a silicone-based member used in the method for producing a composite molded body according to the first aspect include (i) a silicone rubber or a silicone resin cured at room temperature. From the viewpoint of workability, a normal temperature curable silicone composition can be used, and (ii) a heat vulcanized silicone rubber composition such as methyl vinyl silicone that is cured by heating to form a silicone rubber or a silicone resin. The above-mentioned (i) room-temperature curable silicone composition which is soft paste-like or semi-fluid before curing and is preferably a room-temperature curable silicone rubber composition which is cured at room temperature to form silicone rubber. used.
The (i) room-temperature curable silicone composition includes a one-part silicone composition that cures with moisture in the air and a two-part silicone composition that cures with a curing agent. In general, a one-component room-temperature-curing silicone composition has adhesion to a molding apparatus or a different material, but tends to be inferior in releasability and handleability. A two-component room-temperature curable silicone composition exhibiting excellent adhesiveness and excellent handleability, particularly a two-component room-temperature curable silicone rubber composition is preferably used.

Two-pack type room temperature curing silicone compositions are roughly classified into two types, a condensation reaction type and an addition reaction type, depending on the functional groups introduced into the silicone.
In the condensation reaction type, a hydroxyl-terminated reactive diorganopolysiloxane and an alkoxy-terminated reactive diorganopolysiloxane are polymerized with a catalyst such as a tin compound. On the other hand, the addition reaction type includes an organopolysiloxane having an alkenyl group such as a vinyl group and an organohydrogenpolysiloxane having a hydrogen atom bonded to a silicon atom (hydrogenated polysiloxane), platinum, palladium, iridium, rhodium, Using a hydrosilylation catalyst composed of a noble metal compound such as osmium or ruthenium, the reaction is performed at room temperature or under heating (in the case of heating, the temperature is generally 150 ° C. or lower).
In the present invention, since the composite molded body having improved adhesive strength between the polyurethane-based member and the silicone-based member can be produced smoothly, the above-described addition-reactive curable silicone composition is used as the curable silicone composition. The product is preferably used. The addition reaction type curable silicone composition includes (α) a curable silicone composition containing an organohydrogenpolysiloxane having a hydrogen atom bonded to a silicon atom and a hydrosilylation catalyst; or (β) bonded to a silicon atom. Any of the hydrogenated organohydrogenpolysiloxane, the alkenyl group-containing organopolysiloxane, and the curable silicone composition containing the hydrosilylation catalyst can be used.

  The organohydrogenpolysiloxane used in the curable silicone compositions (α) and (β) described above may be an organohydrogenpolysiloxane having at least one hydrogen atom bonded to a silicon atom in one molecule. Any may be sufficient and it does not restrict | limit in particular. Among them, the organohydrogenpolysiloxane is a diorganopolysiloxane bonded to a silicon atom in the diorganopolysiloxane molecule from the viewpoints of flexibility, excellent elastic properties, availability, and curability. Diorganohydrogen polysiloxane in which one or more of monovalent organic groups (organo groups) are replaced by hydrogen atoms is preferably used, and 1 of methyl groups bonded to silicon atoms in dimethylpolysiloxane molecules. More preferably, dimethyl hydrogen polysiloxane in which one or more, particularly 2 to 10 are replaced with hydrogen atoms is used.

  The organopolysiloxane having an alkenyl group used in the curable silicone composition (β) is any organopolysiloxane having at least one alkenyl group such as vinyl group or allyl group in one molecule. Well, not particularly limited. Among them, the organopolysiloxane having the alkenyl group is a diorgano having one or more alkenyl groups bonded to a silicon atom from the viewpoints of flexibility, excellent elastic properties, availability, curability and the like. Polysiloxane is preferably used, and dimethylpolysiloxane in which one or more, particularly 2 to 10, methyl groups bonded to silicon atoms in the dimethylpolysiloxane molecule are replaced with alkenyl groups is more preferably used.

  The molecular weights of the organohydrogenpolysiloxane used in the curable silicone composition (α) and (β) described above and the organopolysiloxane having an alkenyl group used in the curable silicone composition (β) described above are particularly limited. First, a material suitable for each application can be used depending on the intended use of the composite molded article.

  The type of hydrosilylation catalyst used in the curable silicone composition of the above (α) and (β) is not particularly limited, and any conventionally used hydrosilylation catalyst can be used, for example, platinum, There may be mentioned complexes of noble metals such as palladium, iridium, rhodium, osmium and ruthenium; organic peroxides; azo compounds. Among them, a platinum complex having high reactivity and excellent handleability, in particular, an alcohol solution of chloroplatinic acid, a compound in which an aliphatic unsaturated hydrocarbon group-containing compound is coordinated after neutralizing the chloroplatinic acid solution, and the like are preferable. Used.

  The content of the hydrosilylation catalyst in the curable silicone compositions (α) and (β) described above is usually preferably about 1 ppm to 1% by mass, particularly about 10 to 500 ppm, based on the total mass of the organopolysiloxane. Good.

  The content of the hydrosilylation catalyst in the curable silicone composition (β) is usually preferably relative to the total mass of the organohydrogenpolysiloxane having a hydrogen atom bonded to a silicon atom and the organopolysiloxane having an alkenyl group. Is preferably about 1 ppm to 1 mass%, particularly about 10 to 500 ppm.

  The curable silicone composition used in the present invention may be a silicone-based adhesive or printing ink as long as it is curable.

  The silicone-based member (second member) included in the composite molded body of the first aspect may be made of silicone alone or may be made of a silicone composition mainly containing silicone. The silicone content in the silicone-based member is preferably in the range of 50 to 100% by mass, since the adhesive strength between the polyurethane-based member and the silicone-based member can be improved, and 80 to 100% by mass. % Is more preferable, within a range of 95 to 100% by mass is further preferable, and 100% by mass is particularly preferable.

  Examples of the components that can be contained in the silicone composition include a release agent, a reinforcing agent, a colorant, a flame retardant, an ultraviolet absorber, an antioxidant, a hydrolysis resistance improver, a fungicide, and an antibacterial agent. And various additives such as stabilizers; various fibers such as glass fibers and polyester fibers; inorganic substances such as talc and silica; and various coupling agents.

  The composite molded body of the first aspect may consist of only a polyurethane-based member (first member) and a silicone-based member (second member), or may be composed of other materials together with the polyurethane-based member and the silicone-based member. Member [for example, a member made of a polymer other than the specific polyurethane constituting the polyurethane-based member or a polymer composition, paper, fabric, metal, ceramic, wood, etc .; hereinafter simply referred to as “other material member” One or more of certain] may be included.

  The composite molded body of the first aspect includes a layered polyurethane-based member [hereinafter sometimes simply referred to as “polyurethane layer”] and a layered silicone-based member [hereinafter simply referred to as “silicone layer”. Is preferably an adhesive laminate. The number of layers of such a composite molded body is not particularly limited, and may be any of a two-layer structure, a three-layer structure, a four-layer structure, and a five-layer structure or more. Further, in a composite molded body having a polyurethane layer and a silicone layer, when it has a polyurethane layer, a silicone layer, and other material members in the form of layers [hereinafter may be simply referred to as “other material layers”] The polyurethane layer and / or the silicone layer and the other material layer may be adhesively laminated on the entire surface of one surface, or may be adhesively laminated continuously or intermittently (for example, line adhesion, point adhesion, partial adhesion) May be surface adhesive).

Examples of the composite molded body having a polyurethane layer and a silicone layer include, for example, a two-layer structure composed of polyurethane layer / silicone layer; a three-layer structure composed of silicone layer / polyurethane layer / silicone layer; polyurethane layer / silicone layer / 3-layer structure composed of polyurethane layer; 4-layer structure composed of polyurethane layer / silicone layer / polyurethane layer / silicone layer; other material layers (for example, layers composed of paper, fabric, metal, other polymers, etc.) / Silicone 3-layer structure composed of layers / polyurethane layers; 3-layer structure composed of silicone layers / polyurethane layers / other material layers (for example, layers composed of paper, fabric, metal, other polymers, etc.); silicone layers / polyurethane layers / Silicone layer / Polyurethane layer / Other material layers (for example, layers made of paper, fabric, metal, other polymers, etc.) Ranaru 5-layer structure, and the like.
When two or more polyurethane layers are present in one composite molded body, the two or more polyurethane layers are included even if they are exactly the same layer as long as the requirements of the polyurethane-based member described above are satisfied. The layer may be any of different types, contents, layer thicknesses and the like of polyurethane.
Further, when two or more silicone layers are present in one composite molded body, the two or more silicone layers may be the same layer or different layers.

In the composite molded body in which the polyurethane layer and the silicone layer are bonded and laminated as described above, the total thickness of the composite molded body, the thickness of the polyurethane layer, and the thickness of the silicone layer are not particularly limited. Can be adjusted accordingly.
Generally, the thickness of the polyurethane layer (one layer) is 10 μm or more, preferably in the range of 20 to 3,000 μm, more preferably in the range of 50 to 2,000 μm, and the silicone layer (one layer) ) Is in the range of 10 μm or more, preferably in the range of 20 to 3,000 μm, more preferably in the range of 50 to 2,000 μm. Desirable from.
In particular, the polyurethane layer is preferably formed in the form of a film from the viewpoint of ease of production, heat resistance, post-processing process passability, and the like. The thickness of the film is preferably in the range of 20 to 300 μm, more preferably in the range of 30 to 200 μm, and still more preferably in the range of 40 to 150 μm.

  A specific method for curing the curable silicone composition on the polyurethane-based member (first member) is not particularly limited. For example, in a composite composed of a polyurethane-based member or a polyurethane-based member and another material member. A method for producing a composite molded body by coating a curable silicone composition on a polyurethane-based member and curing it; in a state where the polyurethane-based member is placed (inserted) in a mold, the mold is melted while the curable silicone composition is melted A method of filling and curing and adhering and integrating; a method of extruding and adhering, curing and integrating a curable silicone composition onto a polyurethane-based member when the curable silicone composition is thermoplastic Can be adopted. Alternatively, a method of curing a silicone-based adhesive or printing ink as a curable silicone composition on a polyurethane-based member and then curing them can be employed.

  In the composite molded body of the first aspect of the present invention, depending on the properties of the polyurethane-based member and the silicone-based member constituting the composite molded body, the material and properties of other material members constituting the composite molded body, etc. Depending on the, it can be used for various purposes. For example, automotive interior parts such as instrument panels, center panels, center console boxes, door trims, pillars, assist grips, handles, airbag covers; automotive exterior parts such as malls; vacuum cleaner bumpers, per refrigerator, camera grips, electric tools Various key sheets, keyboards, housings, etc. used for grips, household cooking utensils, remote control switches, various key tops for office automation equipment, push button switches (used for mobile phones, home appliances, automobile parts, communication devices, etc.) Home appliance parts; sports equipment such as underwater glasses; various covers; industrial parts with various packing for wear resistance, airtightness, soundproofing, vibration proofing, etc .; curl cord wire covering; belt; hose; tube; Bottom; Watch band; Silencer gear; Conveyor belt; Laminate Goods; various containers; various electric and electronic parts; various mechanical parts; it can be used for a variety of vibration damping materials.

Among these, the composite molded body is a material in which the polyurethane-based member and the silicone-based member are sufficiently bonded without any surface activation treatment, so it can be used for communication terminals such as mobile phones, various instruments, and personal computer input. It can be preferably used as a material constituting a keypad used for a keyboard, an operation unit of a remote controller, or the like. The keypad is formed into a desired size and shape by cutting, punching, cutting, or the like, if necessary, for a composite molded body, preferably a composite molded body in which a polyurethane layer and a silicone layer are bonded and laminated. Can be manufactured. In addition, a desired groove or hole may be formed on the keypad by grinding, laser, or the like. In addition, the keypad has an irregularity for arranging the key top; an irregularity for arranging the pusher for pressing the key switch installed on the lower surface of the key sheet; Various irregularities such as irregularities for enabling the pusher to have a function may be provided. These irregularities can be formed by subjecting the composite molded body to compression molding (press molding), vacuum molding, or the like.
In addition, this invention includes the composite molding for keypads which has the said polyurethane-type member and a silicone-type member.

  By disposing a key top such as a button key at a predetermined position of the keypad, a key sheet having the keypad and the keytop can be obtained. The key sheet may have a pusher in addition to the key top. Arrangement of key tops, pressers, and the like on the keypad can be performed using an adhesive such as a chemically reactive adhesive (such as an adhesive containing cyanoacrylate) or a UV adhesive.

[Composite Molded Body of Second Embodiment]
The composite molded body of the second aspect of the present invention is a composite molded body in which the first member in the composite molded body of the first aspect described above is replaced with the following third member, that is, the following third member and second A composite molded body having a member.
3rd member: The member which consists of a polyurethane composition which contains 0.01-2 mass parts of carboxylates with respect to 100 mass parts of polyurethane (Hereinafter, the said member may be abbreviated as "polyurethane-type member.").
Second member: a member made of silicone alone or made of a silicone composition mainly containing silicone (the same as the second member in the composite molded body of the first aspect described above) (hereinafter referred to as “silicone-based member”) May be abbreviated as ")."

  In the composite molded body of the second aspect, the polyurethane-based member and the silicone-based member are in contact.

  As the polyurethane contained in the polyurethane composition, a thermoplastic polyurethane produced by reacting a polymer polyol, an organic polyisocyanate, and, if necessary, a chain extender can be used.

  As the polymer polyol used in the production of the above polyurethane, any polymer polyol conventionally used in the production of polyurethane can be used. Examples of such polymer polyols include, for example, polyester polyols, polyether polyols, polycarbonate polyols, polyester polycarbonate polyols, polyolefin polyols, conjugated diene polymer polyols that may be hydrogenated, castor oil polyols, and vinyl polymer polyols. Etc. These polymer polyols may be used alone or in combination of two or more. Among these, as the polymer polyol, one or more of polyester polyol, polyether polyol, and polycarbonate polyol are preferably used, and polyester polyol and / or polyether polyol are more preferably used. Alternatively, polyether diol is more preferably used.

  Examples of the polyester polyol include a polyol component (polyol or an ester-forming derivative thereof) and a polycarboxylic acid component (polycarboxylic acid or an ester-forming derivative thereof (ester (lower alkyl ester, aryl ester, Examples include polyester polyols obtained by direct esterification reaction or transesterification reaction of carbonic acid esters and the like) and anhydrides)), and polyester polyols obtained by ring-opening polymerization of lactones using a polyol as an initiator. .

  As the polyol component used in the production of the polyester polyol, those generally used in the production of polyester can be used. Specific examples thereof include polyurethane as a polyurethane-based member in the composite molded body of the first aspect described above. The same thing as the specific example illustrated in the polyol component of the polyester polyol used for manufacture of this is mentioned, One of them may be used independently, or 2 or more types may be used together. Among these, 1,4-butanediol, which is non-adhesive, excellent in melt moldability, excellent in mechanical properties represented by tensile stress and tear strength, and excellent in heat resistance can be obtained. It is preferable to use an aliphatic diol having 4 to 10 carbon atoms such as 3-methyl-1,5-pentanediol, 1,6-hexanediol, 1,8-octanediol, It is more preferable to use a linear aliphatic diol having 4 to 10 carbon atoms such as 6-hexanediol and 1,8-octanediol.

  As the polycarboxylic acid component used in the production of the polyester polyol, those generally used in the production of polyester can be used. For example, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid , Sebacic acid, dodecanedioic acid, methylsuccinic acid, 2-methylglutaric acid, 3-methylglutaric acid, trimethyladipic acid, 2-methyloctanedioic acid, 3,8-dimethyldecanedioic acid, 3,7-dimethyldecanediate Aliphatic dicarboxylic acids having 4 to 12 carbon atoms such as acids; cycloaliphatic dicarboxylic acids such as cyclohexanedicarboxylic acid, dimer acid and hydrogenated dimer acid; aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid, orthofluric acid and naphthalenedicarboxylic acid Acid: Tricarboxylic or higher polycarboxylic acid such as trimellitic acid or pyromellitic acid ; Or the like can be mentioned ester-forming derivatives thereof. These polycarboxylic acid components may be used alone or in combination of two or more. Among them, non-adhesive, excellent melt moldability, excellent mechanical properties represented by tensile stress and tear strength, and polyurethane having excellent heat resistance can be obtained. An acid is preferable, adipic acid, azelaic acid, and sebacic acid are more preferable, and adipic acid is still more preferable.

  Moreover, as lactone used for manufacture of a polyester polyol, (epsilon) -caprolactone, (beta) -methyl-delta-valerolactone, etc. can be mentioned, for example.

  Examples of the polyether polyol include polyethylene glycol, polypropylene glycol, polytetramethylene glycol, and poly (methyltetramethylene glycol) obtained by ring-opening polymerization of a cyclic ether in the presence of a polyol. , One or more of these can be used. Among them, polyurethane that is non-adhesive, excellent in melt moldability, excellent in mechanical properties typified by tensile stress and tear strength, and excellent in heat resistance can be obtained. Therefore, polytetramethylene glycol and / or poly ( Methyl tetramethylene glycol) is preferably used.

  As said polycarbonate polyol, what is obtained by reaction of a polyol component and carbonate compounds, such as a dialkyl carbonate, an alkylene carbonate, a diaryl carbonate, can be mentioned, for example. As the polyol component used for the production of the polycarbonate polyol, the polyol components exemplified above as the components that can be used for the production of the polyester polyol can be used. Examples of the dialkyl carbonate include dimethyl carbonate and diethyl carbonate. Examples of the alkylene carbonate include ethylene carbonate. Examples of the diaryl carbonate include diphenyl carbonate.

  As the above-mentioned polyester polycarbonate polyol, for example, those obtained by simultaneously reacting a polyol component, a polycarboxylic acid component and a carbonate compound, or previously synthesized polyester polyol and polycarbonate polyol, respectively, and then combining them with a carbonate compound. Examples thereof include those obtained by reacting or reacting with a polyol component and a polycarboxylic acid component.

  Specific examples of the polymer polyol include poly (1,4-tetramethylene adipate) diol, poly (3-methyl-1,5-pentamethylene adipate) diol, poly (ε-caprolactone) diol, poly Examples include tetramethylene glycol.

  The number average molecular weight of the polymer polyol is preferably in the range of 500 to 8,000, more preferably in the range of 600 to 5,000, and in the range of 800 to 3,500. Is more preferable, 850 to 1200 is even more preferable, 900 to 1100 is particularly preferable, and 1000 is most preferable. By using a polymer polyol having a number average molecular weight in the above range, mechanical properties such as non-adhesiveness, melt moldability, abrasion resistance, and tensile strength at break, flexibility, flexibility, and low residual strain A polyurethane excellent in various properties such as can be obtained.

  Moreover, as the number of hydroxyl groups per molecule in the above polymer polyol, a thermoplastic polyurethane excellent in melt moldability, non-adhesiveness, abrasion resistance, mechanical properties and the like can be obtained. It is preferably within one range, and more preferably within a range of 2.0 to 2.07.

  As the organic polyisocyanate used in the production of the above polyurethane, any organic polyisocyanate conventionally used in the production of polyurethane can be used. Specific examples thereof include the composite of the first aspect described above. The same thing as the specific example illustrated in the organic polyisocyanate used for manufacture of the polyurethane of the polyurethane-type member in a molded object is mentioned, Even if it uses individually by 1 type of those, or it uses 2 or more types together Good. Among them, 4,4′-diphenylmethane diisocyanate is mainly contained for the same reason as in the composite molded body of the first aspect described above (preferably 50 mol% or more, more preferably 80 mol% or more, and still more preferably 95 It is preferable to contain at least mol%, particularly preferably 100 mol%.

In the production of polyurethane, a chain extender can be used in combination as necessary.
As the chain extender, a low molecular weight compound having two or more active hydrogen atoms and a molecular weight of 400 or less can be used. Specific examples thereof include the polyurethane-based member in the composite molded article of the first aspect described above. The same thing as the specific example illustrated in the chain extender used for manufacture of a polyurethane is mentioned, One of them may be used independently, or 2 or more types may be used together. Moreover, among these, for the same reason as the reason for the polyurethane-based member of the composite molded body of the first aspect described above, an aliphatic diol having 2 to 10 carbon atoms is mainly contained (preferably 50 mol% or more, more preferably 80 Mol% or more, more preferably 95 mol% or more, particularly preferably 100 mol% or more), and mainly contains 1,4-butanediol (preferably 50 mol% or more, more preferably 80 mol% or more, More preferably, it is 95 mol% or more, and particularly preferably 100 mol%.

  When a polyurethane is produced by reacting the above-mentioned polymer polyol, organic polyisocyanate and, if necessary, a chain extender, the mixing ratio of each component is determined according to the hardness and mechanical properties to be imparted to the target polyurethane. Although it is appropriately determined in consideration of performance and the like, the molar ratio of active hydrogen atom: isocyanate group present in the reaction system is 1: 3 for the same reason as that of the polyurethane-based member of the composite molded body of the first aspect described above. It is preferable to use each component in such a ratio that it is in the range of 0.9 to 1.3, and it is more preferable to use each component in a ratio that is in the range of 1: 0.9 to 1.1.

  The method for producing polyurethane follows the method for producing polyurethane in the polyurethane-based member of the composite molded article of the first aspect described above.

  The content rate of the nitrogen atom derived from the isocyanate group in the polyurethane is within the range of 1.5 to 6% by mass from the same reason and viewpoint as that in the polyurethane in the polyurethane-based member of the composite molded body of the first aspect described above. It is preferable that it is within a range of 2 to 5% by mass, and more preferably within a range of 2.5 to 5% by mass.

The polyurethane composition includes a carboxylate. As the carboxylate, a carboxylate group, that is, a compound having one or more groups in the molecule corresponding to a functional group obtained by neutralizing a carboxyl group (—CO ₂ H) into a salt is used. The carboxylate may be a low molecular compound or a high molecular compound.

Specific examples of the carboxylic acid group include a metal salt of a carboxyl group and an ammonium salt of a carboxyl group. Examples of the metal constituting the metal salt of the carboxyl group include alkali metals such as lithium, sodium and potassium; alkaline earth metals such as magnesium and calcium; other than alkali metals and alkaline earth metals such as zinc, copper and aluminum The metal etc. are mentioned. Examples of ammonium constituting the ammonium salt of the carboxyl group include ammonium (NH ₄ ⁺ ); quaternary ammonium such as tetramethylammonium, tetraethylammonium, and tetrabutylammonium. In a compound having two or more carboxylate groups in the molecule, a plurality of carboxylate groups present in the molecule may be the same or different from each other. Among these, the carboxylate group is preferably a metal salt of a carboxyl group, more preferably an alkali metal salt of a carboxyl group, and a sodium salt of a carboxyl group from the viewpoint of availability. Is more preferable.

  Examples of the low molecular weight compound used as the carboxylate include formate, acetate, propionate, butanoate, pentanoate, hexanoate, heptanoate, octanoate, nonanoate, Decanoate, dodecanoate, tetradecanoate, hexadecanoate, heptadecanoate, stearate, montanate, etc., saturated aliphatic monocarboxylate having 1 to 30 carbon atoms; oleate, linoleate , Linolenate, arachidonate, eicosapentaenoate, docosahexaenoate, etc., unsaturated aliphatic monocarboxylate having 3 to 30 carbon atoms; malonate, succinate, glutarate, adipate, C2-C30 aliphatic dicarboxylates such as pimelate, suberate, azelate, sebacate; cyclohexanecarboxylate, cyclo Alicyclic monocarboxylates such as kutancarboxylate; Alicyclic dicarboxylates such as 1,4-cyclohexanedicarboxylate and 1,5-cyclooctanedicarboxylate; benzoate, salicylate, gallic acid Monocarboxylates having aromatic groups such as salts, cinnamate and naphthalenecarboxylate; dicarboxylates having aromatic groups such as phthalate, isophthalate, terephthalate and naphthalene dicarboxylate; Examples thereof include a carboxylate having an aromatic group and three or more carboxylic acid groups, such as merit acid salt, pyromellitic acid salt, and benzene hexacarboxylate. These low molecular weight compounds may be used alone or in combination of two or more. Among these, from the viewpoint of availability and the like, an aliphatic monocarboxylate having 1 to 30 carbon atoms is preferable, and an aliphatic monocarboxylate having 1 to 20 carbon atoms is more preferable.

On the other hand, examples of the polymer compound used as the carboxylate include carboxylate group-containing heavy compounds such as polyolefin having carboxylate group, polystyrene having carboxylate group, and olefin-styrene copolymer having carboxylate group. 1 type or 2 types or more of coalescence is mentioned.
These carboxylate group-containing polymers are obtained by graft polymerization of unsaturated compounds having a carboxyl group or a derivative group thereof (such as an acid anhydride group) such as acrylic acid, methacrylic acid, maleic acid, and maleic anhydride. Using a polymer or a polymer in which the unsaturated compound is copolymerized in the main chain, and reacting this with a basic substance (for example, sodium hydroxide, potassium hydroxide, ammonia, etc.) Can do.
The monomer component constituting the polymer before graft polymerization in the polymer obtained by graft polymerization of the unsaturated compound, or the unsaturated component constituting the polymer in which the unsaturated compound is copolymerized in the main chain. Examples of monomer components other than compounds include α-olefins such as ethylene, propylene, 1-butene, and 1-octene; aromatic vinyls such as styrene.

  The content rate of the carboxylate in a polyurethane composition is 0.01 mass part or more with respect to 100 mass parts of polyurethanes. If the carboxylate content is less than this, the adhesive strength between the polyurethane-based member and the silicone-based member in the resulting composite molded article may be reduced. Moreover, since the unevenness | corrugation of the surface of a polyurethane-type member becomes large and an external appearance tends to deteriorate when there is too much carboxylate content, the content of carboxylate in a polyurethane composition is 100 mass parts of polyurethane. On the other hand, it is preferably within a range of 0.01 to 2 parts by mass, more preferably within a range of 0.01 to 1 part by mass, and within a range of 0.03 to 0.5 parts by mass. Is more preferable.

  The polyurethane composition constituting the polyurethane-based member (third member) of the composite molded body of the second aspect of the present invention may consist of only the above-mentioned polyurethane and carboxylate, or other than both components An ingredient may be further included. The total content of the polyurethane and carboxylate in the polyurethane composition is preferably in the range of 50 to 100% by mass, more preferably in the range of 80 to 100% by mass, and 95 to More preferably within the range of 100% by weight, particularly preferably 100% by weight.

  Examples of components other than the polyurethane and carboxylate described above include, for example, mold release agents, reinforcing agents, colorants, flame retardants, ultraviolet absorbers, antioxidants, hydrolysis resistance improvers, fungicides, and antibacterial agents. Various additives such as agents and stabilizers; various fibers such as glass fibers and polyester fibers; inorganic substances such as talc and silica; various coupling agents and the like.

  The polyurethane is a polyurethane obtained by reacting a polymer polyol, an organic polyisocyanate and a chain extender, which is used for the polyurethane-based member of the composite molded article of the first aspect described above. The ratio of the total of the aromatic dicarboxylic acid unit and the aromatic hydroxycarboxylic acid unit in the total of all dicarboxylic acid units and all hydroxycarboxylic acid units that mainly contain the polyester polyol and constitute the polyester polyol is 30 to 100 mol%. Polyurethane can also be used. In this case, it can be expected to obtain a composite molded body in which the polyurethane-based member (third member) and the silicone-based member (second member) are more firmly bonded.

  The method for producing the polyurethane-based member (third member) of the composite molded body of the second aspect is not particularly limited, and the above-mentioned polyurethane, carboxylate and other components blended as desired are mixed or melt-kneaded. It may be produced using any of the known molding techniques using a polyurethane composition obtained by, for example, injection molding, extrusion molding, inflation molding, blow molding, calendar molding, press molding, It can be formed into various shapes (for example, sheets, films, plates, tubular bodies, rod-shaped bodies, hollow molded bodies, various containers, various block-shaped molded bodies, various molds, etc.) by any molding method such as casting. it can. Among the molding methods described above, it is preferable to employ injection molding, extrusion molding or inflation molding, and it is more preferable to employ extrusion molding or inflation molding using a single screw type extruder. In this case, the cylinder temperature of the single screw extruder is preferably in the range of 180 to 230 ° C.

  The silicone-based member (second member) included in the composite molded body according to the second aspect of the present invention is the same as the silicone-based member included in the composite molded body according to the first aspect described above. The embodiment also follows that of the silicone-based member of the composite molded body of the first aspect described above.

  Further, the number of polyurethane-based members (third members) and silicone-based members (second members) in the composite molded body of the second aspect, the manner of contact between the two members, and the like are also the same as those of the first aspect. As in the case of the composite molded body of the first aspect described above, it is possible to form a composite molded body including members made of other materials other than these two members, and the details of the other materials, etc. This is followed in the composite molded body of the first aspect. Also in the composite molded body of the second aspect, as in the composite molded body of the first aspect, both the polyurethane-based member (third member) and the silicone-based member (second member) are layered members. (Polyurethane layer, silicone layer) and preferably a composite molded body in which they are bonded and laminated. In that case, a two-layer structure, a three-layer structure, a four-layer structure, a multilayer structure of five or more layers Furthermore, it can be a multilayer body having other material members in layers (“other material layers”), and in this multilayer body, the form of adhesion between the polyurethane layer and / or the silicone layer and the other material layers is lined up. The bonding, point bonding, partial surface bonding, and the like can be performed in the same manner as the composite molded body of the first aspect described above, and a specific example of the laminated structure in the multilayer molded composite body is also described in the first embodiment. The composite molded body of the embodiment follows It is. Further, in the case where two or more polyurethane layers and / or two or more silicone layers are present in the composite molded article, the constituent material of each layer, the thickness of the layer, and the like can be variously changed. It is the same as the composite molded body.

In the composite molded body in which the polyurethane layer and the silicone layer are bonded and laminated as described above, the total thickness of the composite molded body, the thickness of the polyurethane layer, and the thickness of the silicone layer are not particularly limited. Can be adjusted accordingly.
Generally, the thickness of the polyurethane layer (one layer) is 10 μm or more, preferably in the range of 20 to 3,000 μm, more preferably in the range of 50 to 2,000 μm, and the silicone layer (one The thickness of the layer) is 10 μm or more, preferably in the range of 20 to 3,000 μm, more preferably in the range of 50 to 2,000 μm. Desirable in terms.
In particular, the polyurethane layer is preferably formed in the form of a film from the viewpoint of ease of production, heat resistance, post-processing process passability, and the like. The thickness of the film is preferably in the range of 20 to 300 μm, more preferably in the range of 30 to 200 μm, and still more preferably in the range of 40 to 150 μm.

  Although it does not restrict | limit especially as a manufacturing method of the composite molded object of the said 2nd aspect, Like the composite molded object of a 1st aspect, even if it does not perform a surface activation process, the adhesive strength of a polyurethane-type member and a silicone-type member is sufficient. Since an improved composite molded body can be easily produced, it is possible to employ a method including a step of forming a silicone-based member on a polyurethane-based member by curing the curable silicone composition on the polyurethane-based member. preferable. The specific method for curing the curable silicone composition on the polyurethane-based member is the same as that in the composite molded body of the first aspect described above.

  The composite molded body of the second aspect depends on the properties of the polyurethane-based member and the silicone-based member constituting the composite molded body, and further on the material and properties of other material members constituting the composite molded body. Thus, it can be used for various purposes. Specific examples include those similar to those exemplified in the composite molded body of the first aspect described above, and among them, the polyurethane-based composite body of the second aspect is not subjected to surface activation treatment. Since the member and the silicone-based member are sufficiently bonded, the communication terminal such as a mobile phone, various instruments, the keyboard for personal computer input, the operation unit of the remote control, etc., like the composite molded body of the first aspect described above It can be preferably used as a material constituting the keypad used in the above. In addition, the manufacturing method of the keypad using the composite molded body of the second aspect, the processing applied to the keypad (cutting, punching, cutting, etc.), and the formation of irregularities for various purposes on the keypad and the forming method thereof And the like in the composite molded body of the first aspect described above. Similarly to the keypad formed by the composite molded body of the first aspect, a key top such as a button key is disposed at a predetermined position of the keypad formed by the composite molded body of the second aspect. Thus, a key sheet having a keypad and a key top can be obtained, and a presser or the like is bonded to the key sheet using a chemically reactive adhesive (such as an adhesive containing cyanoacrylate) or a UV adhesive. It can arrange | position using an agent.

  EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples. In the following examples and comparative examples, the adhesive strength between the polyurethane member and the silicone member and the melt viscosity of the polyurethane were measured or evaluated by the following methods.

(1) Polyurethane melt viscosity:
Using a Koka flow tester (manufactured by Shimadzu Corporation), the melt viscosity of polyurethane dried under reduced pressure at 80 ° C. for 2 hours (10 torr or less), load 490.3 N (50 kgf), nozzle size = diameter 1 mm × length The measurement was performed under conditions of a thickness of 10 mm and a temperature of 200 ° C.

(2) Adhesive strength between polyurethane-based member and silicone-based member:
Using the composite molded bodies obtained in the following examples and comparative examples, the resistance value (adhesive strength) when the polyurethane-based member and the silicone-based member in the 180-degree peel test are peeled off is “ Using an “autograph measuring device IS-500D”, the measurement was performed at room temperature under a tensile speed of 50 mm / min, and used as an index of adhesion.

(3) Measurement of tensile stress (M ₁₀ ) of polyurethane film:
The polyurethane film obtained in the following Examples or Comparative Examples was cut to produce a dumbbell-shaped test piece (width of 5 mm at the center) defined in JIS K 7311-1995. Using an Instron testing machine (Instron Japan Ltd. “Instron 5566”) at a temperature of 23 ° C. and a tensile speed of 300 mm / min, the above dumbbell-shaped test piece was stretched by 10%. The tensile stress was measured and this was taken as the tensile stress (M ₁₀ ) of the polyurethane film.

  Abbreviations and contents relating to the compounds used in the following Examples and Comparative Examples are shown below.

<Polymer polyol>
POH-1 : Polyester diol produced by reacting 3-methyl-1,5-pentanediol and terephthalic acid, having a number of hydroxyl groups per molecule of 2.00 and a number average molecular weight of 1,000
POH-2 : Polyester diol produced by reacting 3-methyl-1,5-pentanediol and isophthalic acid, having a number of hydroxyl groups per molecule of 2.00 and a number average molecular weight of 1,000
POH-3 : Polyester diol produced by reacting 1,4-butanediol and adipic acid and having a number of hydroxyl groups per molecule of 2.00 and a number average molecular weight of 1,000

《Organic polyisocyanate》
MDI : 4,4′-diphenylmethane diisocyanate

《Chain extender》
BD : 1,4-butanediol

《Urethaneization reaction catalyst》
SN : Dibutyltin diacetate

Example 1
(1) A polymer polyol (POH-1) containing 10 ppm of a urethanization reaction catalyst (SN), a chain extender (BD), and an organic polyisocyanate (MDI) having a molar ratio of POH-1: BD: MDI of 1. 00: 2.08: 3.08 (content of nitrogen atom derived from isocyanate group is 4.4% by mass), and these two axes rotate coaxially so that the total supply amount is 200 g / min. Continuous supply to the front of the heating zone of a screw type extruder (30 mmφ, L / D = 36; heating zone divided into three zones: front, center, and rear) and continuous melt polymerization at 260 ° C. The polyurethane formation reaction was performed. The obtained melt was continuously extruded into water as strands, and then cut with a pelletizer to obtain pellets. The obtained pellets were dehumidified and dried at 80 ° C. for 4 hours to produce polyurethane.
(2) Using the polyurethane obtained in (1) above, extrude from a T-die extrusion machine (25 mmφ, cylinder temperature 180 to 200 ° C., die temperature 200 ° C.) onto a 30 ° C. cooling roll and cool. A film (thickness: 100 μm) was formed, and the film was wound at a winding speed of about 2 m / min.
(3) A test piece having a width of 25 mm and a length of 100 mm was cut out from the film (rolled film) obtained in (2) above. A liquid curable silicone composition which is an addition reaction type curable silicone composition ("Shin-Etsu Silicone KE-2030" manufactured by Shin-Etsu Chemical Co., Ltd. (liquid obtained by mixing liquid A and liquid B)) Was applied to a thickness of about 100 μm and allowed to stand in a hot air dryer at 120 ° C. for 3 minutes to obtain a composite molded body having a two-layer structure composed of a polyurethane-based member and a silicone-based member. Using the composite molded body, the adhesive strength between the polyurethane-based member and the silicone-based member was measured by the method described above, and the results are shown in Table 1.

<< Examples 2 to 5, Comparative Examples 1 and 2 >>
(1) Polymer polyol (POH-1, POH-2 and POH-3), chain extender (BD) and organic polyisocyanate (MDI) each containing 10 ppm of urethanization reaction catalyst (SN) are shown in Table 1 below. A polyurethane was produced in the same manner as in Example 1 except that it was used in the proportions shown in (2) and (2).
(2) Using the polyurethane obtained in (1) above, a composite molded body having a two-layer structure composed of a polyurethane-based member and a silicone-based member was obtained in the same manner as in Example 1. The adhesive strength between the polyurethane-based member and the silicone-based member was measured by the method described above using the obtained composite molded body. The results are shown in Table 1.

<< Production Example 1 >>
Production of polyurethane Polymer polyol (POH-3) containing 10 ppm of the above urethanization reaction catalyst (SN), chain extender (BD) and organic polyisocyanate (MDI) have a molar ratio of POH-3: BD: MDI. 1.00: 2.75: 3.75 (content of nitrogen atom derived from isocyanate group is 4.8% by mass), and these are rotated in the coaxial direction so that the total supply amount is 200 g / min. Continuously fed at the front of the heating zone of a twin screw extruder (30 mmφ, L / D = 36; heating zone divided into three zones: front, center, and rear) and continuously melted at 260 ° C Polyurethane formation reaction was carried out by polymerization. The obtained melt was continuously extruded into water as a strand, and then cut with a pelletizer to obtain pellets. The obtained pellets were dehumidified and dried at 80 ° C. for 4 hours to produce polyurethane. The melt viscosity of the polyurethane was measured by the method described above. The results are shown in Table 2.

<< Examples 6 to 9 and Comparative Example 3 >>
Manufacture of composite molded body Dry blended so that the contents of both components in the film obtained in the polyurethane obtained in Production Example 1 and the carboxylate (sodium acetate or sodium stearate) are the values shown in Table 2. (In Comparative Example 3, polyurethane was used alone without using a carboxylate salt), and this was used using a T-die type extruder (25 mmφ, cylinder temperature 180 to 200 ° C., die temperature 200 ° C.). After melt-kneading, the film was extruded and cooled on a 30 ° C. cooling roll to form a film (thickness: 100 μm), and the film composed of the polyurethane composition was produced by winding the film at a winding speed of about 2 m / min.
Next, a test piece having a width of 25 mm and a length of 100 mm was cut out from each of the obtained films (rolled film). A liquid curable silicone composition (“Shin-Etsu Silicone KE-2030” manufactured by Shin-Etsu Chemical Co., Ltd.) (liquid obtained by mixing A liquid and B liquid) was applied to the test piece to a thickness of about 100 μm. The product was left in a hot air dryer for 3 minutes to obtain a composite molded body having a two-layer structure composed of a polyurethane-based member and a silicone-based member. The adhesive strength between the member and the silicone-based member was measured.
The results are shown in Table 2.

<< Production Example 2 >>
Production of polyurethane Polymer polyol (POH-1, POH-3), chain extender (BD), and organic polyisocyanate (MDI) containing 10 ppm of the above urethanization reaction catalyst (SN) were converted into POH-1: POH-3. : BD: MDI molar ratio is 0.50: 0.50: 2.75: 3.75 (content of nitrogen atom derived from isocyanate group is 4.8% by mass), and the total supply amount thereof is 200 g. In front of the heating zone of a twin screw extruder (30 mmφ, L / D = 36; heating zone divided into three zones: front, middle and rear) Polyurethane formation reaction was carried out by continuously supplying to the part and performing continuous melt polymerization at 260 ° C. The obtained melt was continuously extruded into water as a strand, and then cut with a pelletizer to obtain pellets. The obtained pellets were dehumidified and dried at 80 ° C. for 4 hours to produce polyurethane.

Example 10
Production of Composite Molded Body The content of both components in the film obtained from the polyurethane and carboxylate (sodium stearate) obtained in Production Example 2 is 0.05 parts by mass with respect to 100 parts by mass of polyurethane. Then, this was melt-kneaded using a T-die type extruder (25 mmφ, cylinder temperature 180-200 ° C., die temperature 200 ° C.), extruded onto a 30 ° C. cooling roll, and cooled (film thickness) And a film composed of the polyurethane composition was produced by winding the film at a winding speed of about 2 m / min. Where the tensile stress of the polyurethane film (M ₁₀₎ was measured by the method of the above (3), it was 25 (MPa).
Next, a test piece having a width of 25 mm and a length of 100 mm was cut out from the obtained film (rolled film). A liquid curable silicone composition (“Shin-Etsu Silicone KE-2030” manufactured by Shin-Etsu Chemical Co., Ltd.) (liquid obtained by mixing A liquid and B liquid) was applied to the test piece to a thickness of about 100 μm. The product was left in a hot air dryer for 3 minutes to obtain a composite molded body having a two-layer structure composed of a polyurethane-based member and a silicone-based member. The adhesive strength between the member and the silicone-based member was measured, and as a result, the adhesive strength was greater than 500 (g / cm).

According to the present invention, it is possible to obtain a composite molded body in which a polyurethane-containing member and a silicone-containing member are sufficiently bonded without performing a surface activation treatment. The composite molded body is particularly useful as a material constituting a keypad used for a communication terminal such as a mobile phone, various instruments, a personal computer input keyboard, a remote control operation unit, and the like.
This application is based on patent application Nos. 2009-083950 and 2009-089511 filed in Japan, the contents of which are incorporated in full herein.

Claims (12)

A first member that is a member made of polyurethane alone or a polyurethane composition mainly containing polyurethane, and a second member that is a member made of silicone alone or made of a silicone composition mainly containing silicone A composite molded body having
The polyurethane of the first member is a polyurethane obtained by reacting a polymer polyol, an organic polyisocyanate and a chain extender, and the polymer polyol mainly contains a polyester polyol, and all dicarboxylic acids constituting the polyester polyol A composite molded article comprising a polyurethane in which the total proportion of aromatic dicarboxylic acid units and aromatic hydroxycarboxylic acid units in the total of units and all hydroxycarboxylic acid units is 30 to 100 mol%.   It has the 3rd member which is a member which consists of a polyurethane composition which contains 0.01-2 mass parts of carboxylates with respect to 100 mass parts of polyurethane instead of said 1st member, It is characterized by the above-mentioned. The composite molded article described.   The polyurethane is a polyurethane obtained by reacting a polymer polyol, an organic polyisocyanate and a chain extender, wherein the polymer polyol mainly contains a polyester polyol, and all dicarboxylic acid units and all hydroxy constituting the polyester polyol. The composite molded article according to claim 2, which is a polyurethane having a total proportion of aromatic dicarboxylic acid units and aromatic hydroxycarboxylic acid units in a total of carboxylic acid units of 30 to 100 mol%.   The ratio of the sum total of the aromatic dicarboxylic acid unit and aromatic hydroxycarboxylic acid unit which occupies for the sum total of all the dicarboxylic acid units and all the hydroxycarboxylic acid units which comprise the said polyester polyol is 30-95 mol%. A composite molded article according to 1.   The composite molded body according to any one of claims 1 to 4, wherein a thickness of the first member or the third member is 10 to 3000 µm. A first member that is a member made of polyurethane alone or a polyurethane composition mainly containing polyurethane, and a second member that is a member made of silicone alone or made of a silicone composition mainly containing silicone A method for producing a composite molded body having:
The polyurethane of the first member is a polyurethane obtained by reacting a polymer polyol, an organic polyisocyanate and a chain extender,
The polymer polyol mainly contains a polyester polyol, and the ratio of the total of aromatic dicarboxylic acid units and aromatic hydroxycarboxylic acid units in the total of all dicarboxylic acid units and all hydroxycarboxylic acid units constituting the polyester polyol is 30 to 30%. 100 mol%,
A method for producing a composite molded body, wherein the second member is formed by curing a curable silicone composition on the first member. Instead of the first member, a method for producing a composite molded body having a third member which is a member made of a polyurethane composition containing 0.01 to 2 parts by mass of a carboxylate with respect to 100 parts by mass of polyurethane,
The method for producing a composite molded body according to claim 6, wherein the second member is formed by curing the curable silicone composition on the third member.   The polyurethane is a polyurethane obtained by reacting a polymer polyol, an organic polyisocyanate and a chain extender, and an aromatic dicarboxylic acid occupying the total of all dicarboxylic acid units and all hydroxycarboxylic acid units constituting the polyester polyol. The method for producing a composite molded article according to claim 7, wherein the total ratio of the unit and the aromatic hydroxycarboxylic acid unit is made of polyurethane of 30 to 100 mol%.   The ratio of the sum total of the aromatic dicarboxylic acid unit and the aromatic hydroxycarboxylic acid unit in the total of all dicarboxylic acid units and all hydroxycarboxylic acid units constituting the polyester polyol is 30 to 95 mol%. The manufacturing method as described in.   The manufacturing method according to any one of claims 6 to 9, wherein a thickness of the first member or the third member is 10 to 3000 µm.   The keypad formed from the composite molded object of any one of Claims 1-5.   A key sheet having at least the keypad according to claim 11 and a keytop.