Two-component, solvent-free curing adhesive, and polyol component.

Abstract

To provide a two-component, solvent-free curing adhesive that can improve workability and suppress powder sedimentation, and a polyol component used in the said two-component, solvent-free curing adhesive. [Solution] The two-component, solvent-free adhesive contains a polyisocyanate component and a polyol component. The polyol component includes a macropolyol and a powder, with the macropolyol content being 80% by mass or more and the powder content being 0.1% by mass or more and 10% by mass or less. The macropolyol includes a macropolyol that is liquid at 25°C and a macropolyol that is solid at 25°C, with the liquid macropolyol content being 15% by mass or more and 93% by mass or less and the solid macropolyol content being 7% by mass or more and 85% by mass or less.

Description

Technical Field

[0001] The present invention relates to a two-component curable solventless adhesive and a polyol component.

Background Art

[0002] Conventionally, solventless adhesives are known as adhesives for packaging materials. For example, a solventless adhesive composition containing a polyisocyanate and a polyol, wherein the polyisocyanate is a mixture of an adduct of trimethylolpropane and tolylene diisocyanate and isophorone diisocyanate, and the polyol is a mixture of polypropylene glycol, a triol obtained by adding propylene glycol to glycerin, and a polyurethane polyol obtained by reacting 4,4'-diphenylmethane diisocyanate with a powder, has been proposed (see Example 2 of Patent Document 1 below).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] On the other hand, in a solventless adhesive composition, the polyisocyanate and the polyol are prepared separately and each is stored for a long period until its use. And due to this long-term storage, the powder contained in the polyisocyanate and / or the polyol may settle. Also, in a solventless adhesive composition, when the polyisocyanate and / or the polyol is in a solid state, it is heated and melted at the time of use, but after melting, the fluidity may decrease in a short time and the workability may be poor. ​​The present invention provides a two-component, solvent-free adhesive that can improve workability and suppress powder sedimentation, and a polyol component used in the two-component, solvent-free adhesive. [Means for solving the problem]

[0006] The present invention [1] is a two-component, solvent-free adhesive comprising a polyisocyanate component and a polyol component, wherein the polyol component comprises a macropolyol and a powder, with the macropolyol content being 80% by mass or more and the powder content being 0.1% by mass or more and 10% by mass or less, and the macropolyol comprising a liquid macropolyol at 25°C and a solid macropolyol at 25°C, with the liquid macropolyol content being 15% by mass or more and 93% by mass or less and the solid macropolyol content being 7% by mass or more and 85% by mass or less, the present invention is a two-component, solvent-free adhesive.

[0007] The present invention [2] includes the two-component curing solvent-free adhesive described in [1] above, wherein the content ratio of the liquid macropolyol to the macropolyol is 30% by mass or more and 80% by mass or less, and the content ratio of the solid macropolyol is 20% by mass or more and 70% by mass or less.

[0008] The present invention [3] includes the two-component, solvent-free curing adhesive described in [1] or [2] above, wherein the liquid macropolyol is a liquid polycarbonate polyol and the solid macropolyol is a solid polycarbonate polyol.

[0009] The present invention [4] is a two-component, solvent-free curing adhesive according to any one of the above [1] to [3], wherein the average particle size of the powder is 1.0 μm or more and 5.0 μm or less.

[0010] The present invention [5] is a polyol component used in a two-component, solvent-free adhesive described in any one of the above [1] to [4], wherein the polyol component comprises a macropolyol and a powder, wherein the content ratio of the macropolyol to the polyol component is 80% by mass or more, and the content ratio of the powder is 0.1% by mass or more and 10% by mass or less, and the macropolyol comprises a macropolyol that is liquid at 25°C and a macropolyol that is solid at 25°C, wherein the content ratio of the liquid macropolyol to the macropolyol is 15% by mass or more and 93% by mass or less, and the content ratio of the solid macropolyol is 7% by mass or more and 85% by mass or less.

[0011] The present invention [6] is a two-component, solvent-free adhesive comprising a polyisocyanate component and a polyol component, wherein the polyisocyanate component comprises a polyisocyanate that is liquid at 25°C, a polyisocyanate that is solid at 25°C, and a powder, wherein the content ratio of the liquid polyisocyanate to the polyisocyanate component is 15% by mass or more and 90% by mass or less, the content ratio of the solid polyisocyanate is 7% by mass or more and 82% by mass or less, and the content ratio of the powder is 0.1% by mass or more and 10% by mass or less, making it a two-component, solvent-free adhesive. [Effects of the Invention]

[0012] The two-component, solvent-free curing adhesive of the present invention contains a polyisocyanate component and a polyol component. The polyol component also contains a macropolyol and a powder, with the macropolyol content being 80% by mass or more and the powder content being 0.1% by mass or more and 10% by mass or less. The macropolyol also contains a macropolyol that is liquid at 25°C and a macropolyol that is solid at 25°C, with the liquid macropolyol content being 15% by mass or more and 93% by mass or less and the solid macropolyol content being 7% by mass or more and 85% by mass or less.

[0013] Therefore, the two-component, solvent-free adhesive of the present invention can improve the workability of the polyol component and suppress the sedimentation of powders in the polyol component.

[0014] Furthermore, the polyol component of the present invention is used in the above-mentioned two-component, solvent-free curing adhesive. The polyol component comprises a macropolyol and a powder, with the macropolyol content being 80% by mass or more and the powder content being 0.1% by mass or more and 10% by mass or less. The macropolyol comprises a macropolyol that is liquid at 25°C and a macropolyol that is solid at 25°C, with the liquid macropolyol content being 15% by mass or more and 93% by mass or less and the solid macropolyol content being 7% by mass or more and 85% by mass or less.

[0015] Therefore, the polyol component of the present invention makes it possible to improve the workability of the polyol component and suppress the sedimentation of powder in the polyol component.

[0016] Furthermore, the two-component, solvent-free curing adhesive of the present invention contains a polyisocyanate component and a polyol component. The polyisocyanate component includes polyisocyanate that is liquid at 25°C, polyisocyanate that is solid at 25°C, and powder, with the liquid polyisocyanate content being 15% by mass or more and 90% by mass or less, the solid polyisocyanate content being 7% by mass or more and 82% by mass or less, and the powder content being 0.1% by mass or more and 10% by mass or less.

[0017] Therefore, the two-component, solvent-free adhesive of the present invention makes it possible to improve the workability of the polyisocyanate component and suppress the sedimentation of powder in the polyisocyanate component. [Modes for carrying out the invention]

[0018] 1.2-component, solvent-free curing adhesive The two-component curable solventless adhesive contains a polyisocyanate component and a polyol component. These are prepared separately and mixed at the time of use. That is, the two-component curable solventless adhesive is a kit comprising a polyisocyanate component and a polyol component.

[0019] <Polyisocyanate component> The polyisocyanate component contains, for example, a polyisocyanate compound. The polyisocyanate compound is an organic compound having two or more isocyanate groups in the molecule.

[0020] Examples of the polyisocyanate compound include a polyisocyanate monomer, a polyisocyanate derivative, and a prepolymer composition.

[0021] Examples of the polyisocyanate monomer include an aliphatic polyisocyanate, an alicyclic polyisocyanate, an aromatic polyisocyanate, and an araliphatic polyisocyanate. These can be used alone or in combination of two or more.

[0022] Examples of the aliphatic polyisocyanate include an aliphatic diisocyanate. Examples of the aliphatic diisocyanate include trimethylene diisocyanate, tetramethylene diisocyanate, pentamethylene diisocyanate (PDI), 1,6-hexamethylene diisocyanate (HDI), 1,2-propane diisocyanate, 1,2-butane diisocyanate, 2,3-butane diisocyanate, 1,3-butane diisocyanate, 2,4,4-trimethylhexamethylene diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, 2,6-diisocyanate methyl caproate, and lysine diisocyanate.

[0023] Examples of alicyclic polyisocyanates include alicyclic diisocyanates. Examples of alicyclic diisocyanates include isophorone diisocyanate (IPDI), norbornene diisocyanate (NBDI), methylene bis(cyclohexyl isocyanate) (hydrogenated diphenylmethane diisocyanate, H 12 MDI), and bis(isocyanatomethyl)cyclohexane (hydrogenated xylylene diisocyanate, H6XDI).

[0024] Examples of aromatic polyisocyanates include aromatic diisocyanates. Examples of aromatic diisocyanates include tolylene diisocyanate (2,4- or 2,6-tolylene diisocyanate or a mixture thereof) (TDI), diphenylmethane diisocyanate (2,2'- or 2,4'- or 4,4'-diphenylmethane diisocyanate or a mixture thereof) (MDI), phenylene diisocyanate (m- or p-phenylene diisocyanate or a mixture thereof), 4,4'-diphenyldiisocyanate, 1,5-naphthalene diisocyanate (NDI), 4,4'-toluidine diisocyanate (TODI), and 4,4'-diphenyl ether diisocyanate.

[0025] Examples of araliphatic polyisocyanates include araliphatic diisocyanates. Examples of araliphatic diisocyanates include xylylene diisocyanate (1,2- or 1,3- or 1,4-xylylene diisocyanate or a mixture thereof) (XDI), 1,3- or 1,4-tetramethylxylylene diisocyanate or a mixture thereof (TMXDI), and ω,ω'-diisocyanate-1,4-diethylbenzene.

[0026] Examples of polyisocyanate derivatives include the above-mentioned derivatives of polyisocyanate monomers. Examples of polyisocyanate monomer derivatives include polymers, isocyanurate derivatives, allophanate derivatives, polyol derivatives (adducts obtained by adding polyisocyanate monomers to polyhydric alcohols), biuret derivatives, urea derivatives, oxadiazinetrione derivatives, and carbodiimide derivatives of polyisocyanate monomers. These can be used individually or in combination of two or more. Preferably, polyisocyanate derivatives include derivatives of aliphatic polyisocyanates, more preferably allophanate derivatives and biuret derivatives of aliphatic polyisocyanates, and even more preferably allophanate derivatives and biuret derivatives of 1,6-hexamethylene diisocyanate (HDI).

[0027] The prepolymer composition is a composition containing an isocyanate group-terminated prepolymer.

[0028] Isocyanate-terminated prepolymers are reaction products of raw material polyisocyanate and raw material polyol.

[0029] Examples of raw material polyisocyanates include the polyisocyanate monomers and polyisocyanate derivatives mentioned above.

[0030] The raw material polyisocyanates can be used alone or in combination of two or more types.

[0031] Preferably, the raw material polyisocyanates include aromatic polyisocyanates and polyisocyanate derivatives, more preferably diphenylmethane diisocyanate (MDI), isocyanurate derivatives of polyisocyanate monomers, and allophanate derivatives of polyisocyanate monomers, even more preferably diphenylmethane diisocyanate (MDI), isocyanurate derivatives of aliphatic polyisocyanates, allophanate derivatives of aliphatic polyisocyanates, and isocyanurate derivatives of alicyclic polyisocyanates, and particularly preferably diphenylmethane diisocyanate (MDI), isocyanurate derivatives of hexamethylene diisocyanate, allophanate derivatives of hexamethylene diisocyanate, and isocyanurate derivatives of isophorone diisocyanate.

[0032] Examples of raw material polyols include high molecular weight polyols and low molecular weight polyols.

[0033] High molecular weight polyols are organic compounds with two or more hydroxyl groups in their molecule and a relatively high molecular weight. Relatively high molecular weight means that the number-average molecular weight (Mn) is 400 or higher, preferably 500 or higher. The number-average molecular weight is the polystyrene-equivalent molecular weight measured by gel permeation chromatography (the same applies hereafter).

[0034] Examples of high molecular weight polyols include polyether polyols, polyester polyols, polycarbonate polyols, polyurethane polyols, epoxy polyols, vegetable oil polyols, polyolefin polyols, acrylic polyols, and vinyl monomer-modified polyols. These can be used individually or in combination of two or more types.

[0035] Preferred high molecular weight polyols include polyether polyols, polyester polyols, and polyurethane polyols.

[0036] Examples of polyether polyols include polyoxyalkylene polyols. Examples of polyoxyalkylene polyols include polyoxyalkylene (C2-3) polyols and polytetramethylene ether polyols. Examples of polyoxyalkylene (C2-3) polyols include polyoxyethylene diol, polyoxypropylene diol, polyoxyethylene triol, polyoxypropylene triol, and polyoxyethylene-polyoxypropylene polyol (random or block copolymer). Examples of polytetramethylene ether polyols include polytetramethylene ether glycol.

[0037] Examples of polyester polyols include condensed polyester polyols and ring-opened polyester polyols (e.g., polycaprolactone polyols), with condensed polyester polyols being preferred. A method for producing condensed polyester polyols includes, for example, reacting a polybasic acid with a low molecular weight polyol, which will be described later. In other words, condensed polyester polyols are preferably obtained by reacting a polybasic acid with a low molecular weight polyol.

[0038] Examples of polybasic acids include saturated aliphatic dicarboxylic acids, unsaturated aliphatic dicarboxylic acids, aromatic dicarboxylic acids, and acid anhydrides. Examples of saturated aliphatic dicarboxylic acids include adipic acid and sebacic acid. Examples of unsaturated aliphatic dicarboxylic acids include maleic acid, fumaric acid, and itaconic acid. Examples of aromatic dicarboxylic acids include orthophthalic acid, isophthalic acid, and terephthalic acid. Examples of acid anhydrides include maleic anhydride, phthalic anhydride, and trimellitic anhydride. These can be used individually or in combination of two or more types.

[0039] Examples of polyurethane polyols include polyether urethane polyols, polyester urethane polyols, and polyether polyester urethane polyols. Polyether urethane polyols can be obtained, for example, by the reaction of the above-mentioned polyisocyanate compound with a polyether polyol. Polyester urethane polyols can be obtained, for example, by the reaction of the above-mentioned polyisocyanate compound with a polyester polyol. Polyether polyester urethane polyols can be obtained, for example, by the reaction of the above-mentioned polyisocyanate compound with a polyether polyol and a polyester polyol.

[0040] The number-average molecular weight of the high molecular weight polyol is 400 or more, preferably 450 or more, more preferably 500 or more, and also, for example, 5000 or less, preferably 3000 or less, more preferably 2500 or less.

[0041] The average number of functional groups (average number of hydroxyl groups) of high molecular weight polyols is, for example, 2 or more. Alternatively, the average number of functional groups (average number of hydroxyl groups) of high molecular weight polyols is, for example, 6 or less, preferably 4 or less, and more preferably 3 or less.

[0042] The hydroxyl value of high molecular weight polyols is, for example, 20 mg KOH / g or more, preferably 30 mg KOH / g or more, more preferably 40 mg KOH / g or more, and also, for example, 300 mg KOH / g or less, preferably 250 mg KOH / g or less, more preferably 230 mg KOH / g or less. The hydroxyl value can be measured by known hydroxyl value measurement methods (JIS K 0070-1992 (acetylation method)), etc. Examples of hydroxyl value measurement methods include the acetylation method and the phthalation method. (The same applies hereinafter.)

[0043] Low molecular weight polyols are organic compounds that have two or more hydroxyl groups in their molecule and have a relatively low molecular weight. Relatively low molecular weight means that the number-average molecular weight (Mn) is less than 400, preferably 200 or less. Furthermore, the molecular weight of low molecular weight polyols is usually 40 or higher.

[0044] Examples of low molecular weight polyols include dihydric alcohols, trihydric alcohols, and tetrahydric or higher alcohols. Examples of dihydric alcohols include dihydric alcohols having 1 to 8 carbon atoms. Examples of dihydric alcohols having 1 to 8 carbon atoms include ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, neopentyl glycol, diethylene glycol, triethylene glycol, and dipropylene glycol. Examples of trihydric alcohols include glycerin and trimethylolpropane. Examples of tetrahydric or higher alcohols include pentaerythritol and diglycerin. In addition, polymers obtained by addition polymerization of alkylene (C2-C3) oxide to dihydric to tetrahydric alcohols so that the number average molecular weight is less than 400 can also be used as low molecular weight polyols. These can be used individually or in combination of two or more types.

[0045] The raw material polyol preferably consists only of macropolyols and does not contain low molecular weight polyols.

[0046] The isocyanate-terminated prepolymer is obtained by prepolymerizing (urethaneizing) the raw material polyisocyanate and raw material polyol.

[0047] The method for obtaining isocyanate-terminated prepolymers is not particularly limited and includes known reaction methods, such as reacting a raw material polyisocyanate and a raw material polyol under a nitrogen atmosphere. The reaction temperature is, for example, 50°C or higher and 150°C or lower, preferably 100°C or lower. The reaction time is, for example, 0.5 hours or more, preferably 1 hour or more and 15 hours or less. The reaction may also be carried out in the presence of a known solvent if necessary. In this case, the solvent is not included in the prepolymer composition.

[0048] Furthermore, in the prepolymerization reaction, the equivalent ratio (NCO / OH) of the isocyanate groups of the raw material polyisocyanate to the hydroxyl groups of the raw material polyol is, for example, greater than 1.0, preferably 2.0 or more, more preferably 4.0 or more, even more preferably 6.0 or more, and also, for example, 15.0 or less, preferably 12.0 or less, more preferably 10.0 or less, and even more preferably 9.0 or less.

[0049] Furthermore, known additives may be added to the above reaction as needed. Examples of additives include urethane catalysts, reaction stoppers, stabilizers, antioxidants, and co-catalysts. The addition ratio and timing can be adjusted as appropriate depending on the purpose and application.

[0050] This yields a prepolymer composition as a reaction solution containing an isocyanate-terminated prepolymer.

[0051] The prepolymer composition (reaction solution) contains an isocyanate-terminated prepolymer, which is the reaction product of the raw material polyisocyanate and raw material polyol. The prepolymer composition (reaction solution) may also contain unreacted raw material polyisocyanate.

[0052] If necessary, some or all of the unreacted raw material polyisocyanate can be removed from the prepolymer composition by known methods. Alternatively, if necessary, further unreacted raw material polyisocyanate can be added to the prepolymer composition.

[0053] Furthermore, if the prepolymer composition does not contain unreacted raw material polyisocyanate, the prepolymer composition consists of an isocyanate group-terminated prepolymer.

[0054] The isocyanate group concentration of the prepolymer composition is, for example, 5% by mass or more, preferably 6% by mass or more, more preferably 7% by mass or more, and even more preferably 8% by mass or more, and also, for example, 40% by mass or less, preferably 30% by mass or less, more preferably 20% by mass or less, and even more preferably 15% by mass or less. The isocyanate group concentration is measured, for example, using a potentiometric titrator in accordance with the toluene / dibutylamine hydrochloric acid method in accordance with JIS K-1603-1 (2007) (the same applies hereinafter).

[0055] The number-average molecular weight of the prepolymer composition is, for example, 400 or more, preferably 600 or more, more preferably 800 or more, and also, for example, 4000 or less, preferably 3000 or less, more preferably 2000 or less.

[0056] The polyisocyanate component can be used alone or in combination of two or more types. Preferred polyisocyanate components include polyisocyanate derivatives and prepolymer compositions.

[0057] <Polyol components> The polyol component includes macropolyols and powders.

[0058] [Macropolyol] Macropolyols are relatively high molecular weight organic compounds that have two or more hydroxyl groups in their molecule. Relatively high molecular weight means that the number-average molecular weight (Mn) is 300 or higher, preferably 500 or higher. The number-average molecular weight is the polystyrene-equivalent molecular weight measured by gel permeation chromatography (the same applies hereafter).

[0059] The macropolyol comprises a macropolyol that is liquid at 25°C and a macropolyol that is solid at 25°C, and preferably consists of a macropolyol that is liquid at 25°C and a macropolyol that is solid at 25°C.

[0060] (Liquid macropolyol) A macropolyol that is liquid at 25°C is a macropolyol that is fluid in an environment at 25°C.

[0061] Examples of macropolyols that are liquid at 25°C (hereinafter sometimes simply referred to as liquid macropolyols) include liquid polycarbonate polyols, liquid polyether polyols, liquid polyester polyols, liquid polyurethane polyols, liquid epoxy polyols, liquid vegetable oil polyols, liquid polyolefin polyols, liquid acrylic polyols, and liquid vinyl monomer-modified polyols. Preferably, these are liquid polycarbonate polyols, liquid polyether polyols, and liquid polyester polyols.

[0062] Liquid polycarbonate polyols can be obtained, for example, by the reaction of a carbonate group-containing compound with a polyhydric alcohol.

[0063] Examples of carbonate group-containing compounds include dimethyl carbonate, diethyl carbonate, dibutyl carbonate, diphenyl carbonate, and ethylene carbonate. These can be used individually or in combination of two or more types.

[0064] Examples of polyhydric alcohols include branched-chain polyhydric alcohols and straight-chain polyhydric alcohols. Branched-chain polyhydric alcohols are polyhydric alcohols that have a branched structure in the linkage between hydrocarbon groups and hydroxyl groups, while straight-chain polyhydric alcohols are polyhydric alcohols that do not have a branched structure in the linkage between hydrocarbon groups and hydroxyl groups.

[0065] Examples of branched polyhydric alcohols include branched dihydric alcohols, branched trihydric alcohols, and branched tetrahydric or higher alcohols. Examples of branched dihydric alcohols include branched dihydric alcohols with 3 to 20 carbon atoms, and preferably branched dihydric alcohols with 3 to 8 carbon atoms. Examples of branched dihydric alcohols with 3 to 8 carbon atoms include 1,2-propanediol, 2-methyl-1,2-propanediol, 2-methyl-1,3-propanediol, 2,2-dimethyl-1,3-propanediol (neopentyl glycol), 1,2-butanediol, 1,3-butanediol, 2,3-butanediol, 2-methyl-1,4-butanediol, 2,2-dimethyl-1,4-butanediol, 1,2-pentanediol, and 1,3-pentanediol. Examples include benzodiol, 1,4-pentanediol, 2,4-pentanediol, 2-methyl-1,5-pentanediol, 2,3-pentanediol, 1,2-hexanediol, 1,3-hexanediol, 1,4-hexanediol, 1,5-hexanediol, 2,3-hexanediol, 2,4-hexanediol, 2,5-hexanediol, 3,4-hexanediol, 1,4-cyclohexanedimethanol, and dipropylene glycol. Examples of branched-chain trihydric alcohols include glycerin and trimethylolpropane. Examples of branched-chain tetrahydric or higher alcohols include pentaerythritol and diglycerin.

[0066] Examples of linear polyhydric alcohols include linear dihydric alcohols. Examples of linear dihydric alcohols include linear dihydric alcohols having 2 to 20 carbon atoms, and more preferably linear dihydric alcohols having 2 to 8 carbon atoms. Examples of linear dihydric alcohols having 2 to 8 carbon atoms include ethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, diethylene glycol, and triethylene glycol.

[0067] Liquid polycarbonate polyols are obtained by reacting the above-mentioned carbonate group-containing compound with the above-mentioned polyhydric alcohol. The carbonate group-containing compound and the polyhydric alcohol are appropriately selected so that the polycarbonate polyol becomes a liquid. Examples of such polyhydric alcohols include branched polyhydric alcohols, mixtures of branched polyhydric alcohols and straight polyhydric alcohols, and mixtures of two or more straight polyhydric alcohols. In other words, the above polyhydric alcohols are preferably branched polyhydric alcohols, mixtures of branched polyhydric alcohols and straight polyhydric alcohols, and / or mixtures of two or more straight polyhydric alcohols.

[0068] Preferably, branched polyhydric alcohols include branched dihydric alcohols, and more preferably, 2-methyl-1,3-propanediol. Preferably, a mixture of branched polyhydric alcohols and straight polyhydric alcohols includes a mixture of branched dihydric alcohols and straight dihydric alcohols, and more preferably, a mixture of 1,4-butanediol and 2-methyl-1,3-propanediol (for example, a molar ratio of 50 / 50). Preferably, a mixture of two or more straight polyhydric alcohols includes a mixture of two or more straight dihydric alcohols, and more preferably, a mixture of 1,5-pentanediol and 1,6-hexanediol (for example, a molar ratio of 50 / 50).

[0069] Furthermore, liquid polycarbonate polyols are also available commercially.

[0070] Examples of liquid polyether polyols include branched alkyl-modified polytetramethylene ether glycol, polyoxypropylene diol, polyoxypropylene triol, polyoxypropylene tetraol, polytrimethylene ether glycol, polyethylene glycol with a number average molecular weight of less than 1000, and copolymer polyols of polyoxyethylene and polyoxypropylene. Examples of branched alkyl-modified polytetramethylene ether glycols include copolymers of tetrahydrofuran and neopentyl glycol, and copolymers of tetrahydrofuran and 2-methyltetrahydrofuran. Liquid polyether polyols are also available commercially.

[0071] Liquid polyester polyols can be obtained, for example, by reacting a known polybasic acid with a known low molecular weight polyol. Examples of polybasic acids include those listed above in the section on polyester polyols (high molecular weight polyols). Examples of low molecular weight polyols include those listed above in the section on raw material polyols. The polybasic acid and the low molecular weight polyol are appropriately selected so that the polyester polyol becomes liquid. Preferred polybasic acids include saturated aliphatic dicarboxylic acids, and more preferably adipic acid. Preferred low molecular weight polyols include dihydric alcohols, more preferably dihydric alcohols having 1 to 8 carbon atoms, and even more preferably neopentyl glycol. In other words, preferred liquid polyester polyols are reaction products of saturated aliphatic dicarboxylic acids and dihydric alcohols having 1 to 8 carbon atoms, and more preferably reaction products of adipic acid and neopentyl glycol. Liquid polyester polyols can also be obtained commercially.

[0072] Liquid macropolyols can be used alone or in combination of two or more types. Preferably, the liquid macropolyol is a liquid polycarbonate polyol. In other words, the liquid macropolyol is preferably a liquid polycarbonate polyol.

[0073] The number-average molecular weight of the liquid macropolyol is, for example, 300 or more, preferably 500 or more, more preferably 600 or more, even more preferably 700 or more, and also, for example, 3000 or less, preferably 2000 or less, more preferably 1500 or less, even more preferably 1000 or less.

[0074] The average number of functional groups (average number of hydroxyl groups) of a liquid macropolyol is, for example, 2 or more, and also, for example, 6 or less, preferably 4 or less, more preferably 3 or less, and even more preferably 2.5 or less. The average number of functional groups (average number of hydroxyl groups) of a liquid macropolyol is particularly preferably 2.

[0075] The hydroxyl value of the liquid macropolyol is, for example, 30 mg KOH / g or more, preferably 50 mg KOH / g or more, more preferably 70 mg KOH / g or more, even more preferably 100 mg KOH / g or more, and also, for example, 400 mg KOH / g or less, preferably 300 mg KOH / g or less, more preferably 200 mg KOH / g or less, and even more preferably 170 mg KOH / g or less.

[0076] The content ratio of liquid macropolyol to macropolyol is 15% by mass or more, preferably 20% by mass or more, more preferably 30% by mass or more, even more preferably 40% by mass or more, even more preferably 50% by mass or more, and particularly preferably 60% by mass or more.

[0077] If the proportion of liquid macropolyol relative to the macropolyol is above the lower limit mentioned above, the workability of the polyol component can be improved. On the other hand, if the proportion of liquid macropolyol relative to the macropolyol is below the lower limit mentioned above, the improvement in the workability of the polyol component is insufficient.

[0078] Furthermore, the content ratio of liquid macropolyol to macropolyol is 93% by mass or less, preferably 85% by mass or less, more preferably 80% by mass or less, even more preferably 77% by mass or less, even more preferably 75% by mass or less, and particularly preferably 70% by mass or less.

[0079] If the ratio of liquid macropolyol to macropolyol is below the above upper limit, the sedimentation of powder in the polyol component can be suppressed. On the other hand, if the ratio of liquid macropolyol to macropolyol exceeds the above upper limit, the suppression of powder sedimentation of the polyol component will be insufficient.

[0080] The content ratio of liquid macropolyol to macropolyol is 15% to 93% by mass, preferably 20% to 85% by mass, more preferably 30% to 80% by mass, even more preferably 40% to 77% by mass, even more preferably 50% to 75% by mass, and particularly preferably 60% to 70% by mass.

[0081] (Solid macropolyols) A macropolyol that is solid at 25°C is a macropolyol that does not have fluidity under the conditions of 25°C.

[0082] Examples of macropolyols that are solid at 25°C (hereinafter sometimes simply referred to as solid macropolyols) include solid polycarbonate polyols, solid polyether polyols, solid polyester polyols, solid polyurethane polyols, solid epoxy polyols, solid vegetable oil polyols, solid polyolefin polyols, solid acrylic polyols, and solid vinyl monomer-modified polyols, with solid polycarbonate polyols and solid polyether polyols being preferred.

[0083] Solid polycarbonate polyols are obtained by reacting the above-mentioned carbonate group-containing compound with the above-mentioned polyhydric alcohol. The carbonate group-containing compound and the polyhydric alcohol are appropriately selected so that the polycarbonate polyol becomes a solid. Examples of such polyhydric alcohols include a single type of linear polyhydric alcohol. In other words, the above-mentioned polyhydric alcohol is preferably a single type of linear polyhydric alcohol.

[0084] Preferably, one linear dihydric alcohol is used as the linear polyhydric alcohol, and more preferably, 1,6-hexanediol is used.

[0085] Furthermore, solid polycarbonate polyols are also available commercially.

[0086] Examples of solid polyether polyols include polytetramethylene ether glycol and polyethylene glycol with a number average molecular weight of 1000 or more. Solid polyether polyols are also available commercially.

[0087] Solid polyester polyols can be obtained, for example, by reacting a known polybasic acid with a known low molecular weight polyol. Examples of polybasic acids include those listed above for polyester polyols (high molecular weight polyols). Examples of low molecular weight polyols include those listed above for raw material polyols. The polybasic acid and the low molecular weight polyol are appropriately selected so that the polyester polyol becomes a solid. Preferred polybasic acids include saturated aliphatic dicarboxylic acids, more preferably adipic acid and sebacic acid, and even more preferably adipic acid. Preferred low molecular weight polyols include dihydric alcohols, more preferably dihydric alcohols having 1 to 8 carbon atoms, even more preferably ethylene glycol, 1,4-butanediol, and propylene glycol, and particularly preferably ethylene glycol and 1,4-butanediol. In other words, as solid polyester polyols, preferred are reaction products of saturated aliphatic dicarboxylic acids and dihydric alcohols having 1 to 8 carbon atoms, and more preferably are reaction products of adipic acid with ethylene glycol and 1,4-butanediol. Solid polyester polyols can also be obtained commercially.

[0088] Solid macropolyols can be used alone or in combination of two or more types. A preferred solid macropolyol is a solid polycarbonate polyol. In other words, the solid macropolyol is preferably a solid polycarbonate polyol.

[0089] The number-average molecular weight of the solid macropolyol is, for example, 300 or more, preferably 400 or more, more preferably 450 or more, even more preferably 500 or more, and also, for example, 3000 or less, preferably 2000 or less, more preferably 1000 or less, even more preferably 800 or less.

[0090] The average number of functional groups (average number of hydroxyl groups) of a solid macropolyol is, for example, 2 or more, and also, for example, 6 or less, preferably 4 or less, more preferably 3 or less, and even more preferably 2.5 or less. The average number of functional groups (average number of hydroxyl groups) of a solid macropolyol is particularly preferably 2.

[0091] The hydroxyl value of the solid macropolyol is, for example, 30 mg KOH / g or more, preferably 50 mg KOH / g or more, more preferably 100 mg KOH / g, even more preferably 120 mg KOH / g or more, and also, for example, 400 mg KOH / g or less, preferably 300 mg KOH / g or less, more preferably 250 mg KOH / g or less, and even more preferably 230 mg KOH / g or less.

[0092] The content ratio of solid macropolyol to macropolyol is 7% by mass or more, preferably 15% by mass or more, more preferably 20% by mass or more, even more preferably 23% by mass or more, even more preferably 25% by mass or more, and particularly preferably 30% by mass or more.

[0093] If the proportion of solid macropolyol relative to the macropolyol is above the lower limit mentioned above, the sedimentation of powder in the polyol component can be suppressed. On the other hand, if the proportion of solid macropolyol relative to the macropolyol is below the lower limit mentioned above, the suppression of powder sedimentation in the polyol component is insufficient.

[0094] Furthermore, the content ratio of solid macropolyol to macropolyol is 85% by mass or less, preferably 80% by mass or less, more preferably 70% by mass or less, even more preferably 60% by mass or less, even more preferably 50% by mass or less, and particularly preferably 40% by mass or less.

[0095] If the ratio of solid macropolyol to macropolyol is below the above upper limit, the workability of the polyol component can be improved. On the other hand, if the ratio of solid macropolyol to macropolyol exceeds the above upper limit, the improvement in the workability of the polyol component will be insufficient.

[0096] The content ratio of solid macropolyol to macropolyol is 7% to 85% by mass, preferably 15% to 80% by mass, more preferably 20% to 70% by mass, even more preferably 23% to 60% by mass, even more preferably 25% to 50% by mass, and particularly preferably 30% to 40% by mass.

[0097] The mass ratio of liquid macropolyol to solid macropolyol is, for example, 0.15 or more, preferably 0.3 or more, more preferably 0.5 or more, even more preferably 0.8 or more, even more preferably 1.0 or more, and particularly preferably 1.5 or more, and also, for example, 15 or less, preferably 10 or less, more preferably 5 or less, and even more preferably 3 or less.

[0098] The content ratio of macropolyol to polyol component is 80% by mass or more, preferably 83% by mass or more, and more preferably 85% by mass or more.

[0099] If the ratio of macropolyol to polyol component is above the lower limit mentioned above, the workability of the polyol component can be improved and the sedimentation of powder in the polyol component can be suppressed.

[0100] Furthermore, the content ratio of macropolyol to polyol component is, for example, 99.9% by mass or less, preferably 99% by mass or less, and more preferably 97% by mass or less.

[0101] The content ratio of macropolyol to polyol component is, for example, 80% to 99.9% by mass, preferably 83% to 99% by mass, and more preferably 85% to 97% by mass.

[0102] [powder] The powder is a particle that improves the appearance of the adhesive layer (described later) obtained by curing the two-component, solvent-free adhesive described later.

[0103] Examples of powders include inorganic particles and organic particles.

[0104] Examples of inorganic particles include oxides, nitrides, carbides, carbonates, sulfates, hydroxides, and silicates. Examples of oxides include alumina, silica, titania, zirconia, magnesia, ceria, yttria, zinc oxide, and iron oxide. Examples of nitrides include silicon nitride, titanium nitride, and boron nitride. Examples of carbides include silicon carbide. Examples of carbonates include magnesium carbonate and calcium carbonate. Examples of sulfates include magnesium sulfate and aluminum sulfate. Examples of hydroxides include aluminum hydroxide and aluminum hydroxide oxide. Examples of silicates include talc, kaolinite, decite, nacrite, halloysite, pyrophyllite, montmorillonite, sericite, mica, amethyst, bentonite, asbestos, zeolite, calcium silicate, magnesium silicate, diatomaceous earth, silica sand, and glass.

[0105] Examples of organic particles include benzoguanamine resin, silicone resin, styrene resin, crosslinked polystyrene, epoxy resin, phenolic resin, fluororesin, polyethylene resin, polyester resin, polyimide resin, polyamide resin, polyacetal resin, polyurethane resin, vinyl acetate copolymer resin, polyphenylene oxide resin, nylon 6, nylon 12, cellulose, acrylic resin, and methacrylic resin, with acrylic resin being preferred.

[0106] Preferably, the powder is an inorganic particle, more preferably a silicate, and even more preferably a zeolite.

[0107] The primary particle size of the powder (measurement method: direct observation with a transmission electron microscope or optical microscope) is, for example, 0.01 μm or more, preferably 0.1 μm or more, more preferably 0.5 μm or more, and also, for example, 5.0 μm or less, preferably 4.0 μm or less, more preferably 3.0 μm or less.

[0108] Furthermore, the average particle size (secondary particle size) of the powder (measurement method: laser diffraction / scattering method) is, for example, 0.5 μm to 10.0 μm, preferably 1.0 μm to 5.0 μm, and more preferably 2.0 μm to 3.0 μm.

[0109] Furthermore, the average particle size (secondary particle size) of the powder is, for example, 0.5 μm or more, preferably 1.0 μm or more, more preferably 2.0 μm or more, and also, for example, 10.0 μm or less, preferably 5.0 μm or less, more preferably 3.0 μm or less.

[0110] The proportion of powder relative to the polyol component is 0.1% by mass or more, preferably 0.5% by mass or more, and more preferably 1% by mass or more.

[0111] If the proportion of powder relative to the polyol component is above the lower limit mentioned above, the appearance of the adhesive layer obtained by curing the two-component solvent-free adhesive can be improved.

[0112] Furthermore, the proportion of powder relative to the polyol component is 10% by mass or less, preferably 5% by mass or less, and more preferably 3% by mass or less.

[0113] If the powder content is below the above upper limit, the sedimentation of the polyol component powder can be suppressed.

[0114] The proportion of powder relative to the polyol component is 0.1% to 10% by mass, preferably 0.5% to 5% by mass, and more preferably 1% to 3% by mass.

[0115] [Optional ingredients] The polyol component may optionally include a low molecular weight polyol. If the polyol component includes a low molecular weight polyol, the polyol component will consist of a macropolyol, a powder, and the low molecular weight polyol.

[0116] Examples of low molecular weight polyols include the low molecular weight polyols listed above as raw material polyols.

[0117] Low molecular weight polyols can be used alone or in combination of two or more types. Preferred low molecular weight polyols include dihydric and trihydric alcohols having 1 to 8 carbon atoms, and more preferably dipropylene glycol and trimethylolpropane. In other words, the low molecular weight polyol is preferably a dihydric alcohol and / or trihydric alcohol having 1 to 8 carbon atoms, and more preferably dipropylene glycol and / or trimethylolpropane.

[0118] When the polyol component includes a low molecular weight polyol, the content ratio of the low molecular weight polyol to the polyol component is, for example, 1% by mass or more, preferably 3% by mass or more, more preferably 5% by mass or more, more preferably 8% by mass or more, and even more preferably 10% by mass or more, and also, for example, 30% by mass or less, preferably 25% by mass or less, more preferably 20% by mass or less, and even more preferably 15% by mass or less.

[0119] Furthermore, the polyol component may contain known additives as needed. Examples of additives include silane coupling agents, reaction solvents, catalysts, epoxy resins, coating properties modifiers, leveling agents, defoamers, antioxidants, UV absorbers, plasticizers, surfactants, pigments, fillers, organic or inorganic fine particles, and antifungal agents. The amount of additives is adjusted as appropriate depending on the purpose and application.

[0120] In particular, when the polyol component contains a silane coupling agent, the content ratio of the silane coupling agent to the polyol component is, for example, 0.1% by mass or more, preferably 0.5% by mass or more, and also, for example, 2.0% by mass or less, preferably 1.5% by mass or less.

[0121] Examples of silane coupling agents include epoxy group-containing silane coupling agents and amino group-containing silane coupling agents.

[0122] Examples of epoxy group-containing silane coupling agents include 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, and 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane. Epoxy group-containing silane coupling agents are also commercially available. These can be used individually or in combination of two or more types.

[0123] Examples of amino group-containing silane coupling agents include 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, N-2-(aminoethyl)-3-aminopropylmethyldimethoxysilane, N-2-(aminoethyl)-3-aminopropyltrimethoxysilane, and N-2-(aminoethyl)-3-aminopropyltriethoxysilane. Amino group-containing silane coupling agents are also commercially available. These can be used individually or in combination of two or more types.

[0124] <Two-component, solvent-free adhesive> The two-component, solvent-free curing adhesive is obtained by separately preparing and combining the above-mentioned polyisocyanate component (curing agent) and the above-mentioned polyol component (main component). Furthermore, the polyisocyanate and polyol components of the two-component, solvent-free curing adhesive are blended at the time of use.

[0125] In the formulation of the polyisocyanate component and the polyol component, the equivalent ratio (NCO / OH) of isocyanate groups in the polyisocyanate component to hydroxyl groups in the polyol component is, for example, 0.9 or more, preferably 1.0 or more, more preferably 1.5 or more, and even more preferably 1.6 or more, and also, for example, 4.0 or less, preferably 3.0 or less, more preferably 2.5 or less, and even more preferably 2.2 or less.

[0126] Furthermore, known additives may be appropriately blended into the polyisocyanate component (curing agent) as needed. Examples of additives include silane coupling agents, reaction solvents, catalysts, epoxy resins, coating properties improvers, leveling agents, defoamers, antioxidants, UV absorbers, plasticizers, surfactants, pigments, fillers, organic or inorganic fine particles, and antifungal agents. The amount of additives blended is appropriately adjusted according to the purpose and application.

[0127] Such two-component, solvent-free adhesives can be used, for example, as adhesives for laminate composite films.

[0128] A laminate composite film is, for example, a laminate comprising two adherends and an adhesive layer placed between the two adherends.

[0129] Examples of adherends include plastic films, metal films, and composite films.

[0130] Examples of plastic films include polyolefin films, polyester films, cellophane films, ethylene-vinyl acetate copolymer films, polyamide films, polyvinyl chloride films, polyvinylidene chloride films, polyvinyl alcohol films, ethylene-vinyl alcohol copolymer films, polycarbonate films, polystyrene films, and polyacrylonitrile copolymer films, with polyolefin films and polyester films being preferred.

[0131] Examples of polyolefins include polyethylene film and polypropylene film. Examples of polyester films include polyethylene terephthalate film, polybutylene terephthalate film, and polyalkylene naphthalate film.

[0132] Furthermore, the plastic film may be an unoriented film, a uniaxially oriented film, or a biaxially oriented film.

[0133] Examples of metal films include metal plates and metal foils. Examples of metals include aluminum, gold, silver, copper, nickel, zinc, titanium, cobalt, indium, and chromium.

[0134] Examples of composite films include laminated films of the above-mentioned plastic film and the above-mentioned metal foil. Furthermore, examples of composite films include vapor-deposited films (composite films of a plastic film and a vapor-deposited layer) in which a metal and / or its oxide is vapor-deposited onto a plastic film (adherent), as described later.

[0135] A plastic film is a preferred adherend.

[0136] The adherend may be surface-treated by known methods. Examples of surface treatments include plasma treatment, vapor deposition treatment, and coating treatment. These can be used individually or in combination of two or more. Preferably, the surface treatments include vapor deposition treatment and coating treatment.

[0137] In the vapor deposition process, for example, a vapor-deposited layer is formed on the above-mentioned substrate by a known method. Examples of vapor-deposited layers include an aluminum layer, an alumina layer, a silicon dioxide layer, and a silicate layer.

[0138] In the coating process, for example, the coating is applied to the substrate by a known method and then dried. Examples of coating materials include known anchor coating materials, gas barrier coating materials, and heat-sealable coating materials. These can be used individually or in combination of two or more types.

[0139] The adhesive layer is obtained by curing a two-component solvent-free adhesive (more specifically, a mixture of the polyisocyanate and polyol components of a two-component solvent-free adhesive). That is, the adhesive layer contains a cured product of a two-component solvent-free adhesive, and preferably consists of a cured product of a two-component solvent-free adhesive.

[0140] Specifically, as a method for manufacturing laminate composite films, first, a polyisocyanate component and a polyol component are mixed to obtain a mixture.

[0141] Next, the mixture is applied to the surface of one of the two adherends. Then, the coated surface is attached to the surface of the other adherend. The two-component solvent-free adhesive is then cured. The curing conditions are, for example, a curing temperature of 10°C to 60°C and a curing time of 12 hours to 168 hours. As a result, the two-component solvent-free adhesive cures between the two adherends, forming an adhesive layer. The result is a laminate composite film comprising two adherends and an adhesive layer. The two-component solvent-free adhesive acts as an adhesive layer, bonding the two adherends together.

[0142] The applications of laminate composite films are not particularly limited, and they are suitably used as packaging materials in various industrial fields. Such industrial fields include, for example, food, beverages, pharmaceuticals, quasi-drugs, and toiletries such as detergents.

[0143] 2. Effects The above two-component, solvent-free curing adhesive contains a polyisocyanate component and a polyol component. The polyol component also contains macropolyol and powder, with the macropolyol content being 80% by mass or more and the powder content being 0.1% by mass or more and 10% by mass or less. Furthermore, the macropolyol includes both liquid macropolyol at 25°C and solid macropolyol at 25°C, with the liquid macropolyol content being 15% by mass or more and 93% by mass or less and the solid macropolyol content being 7% by mass or more and 85% by mass or less.

[0144] Therefore, the above-described two-component, solvent-free curing adhesive can improve the workability of the polyol component and suppress the sedimentation of powder within the polyol component.

[0145] In detail, in two-component solvent-free adhesives, the polyisocyanate component and the polyol component are mixed at the time of use. Furthermore, the powder is, for example, contained in the polyol component. The powder is added, for example, to improve the appearance of the coating film of the two-component solvent-free adhesive. For example, when using a solid polyol component, the solid polyol component is first heated and melted, then mixed with a polyisocyanate component to be used as a two-component, solvent-free adhesive. However, if the proportion of solid macropolyol in the polyol component is extremely high, the polyol component will solidify again in a short time even after melting. The solidified polyol component lacks fluidity and cannot be dispensed during use. Furthermore, when such a polyol component is mixed with a polyisocyanate component, the mixture solidifies relatively quickly due to the influence of the polyol component, which tends to reduce the fluidity of the two-component, solvent-free adhesive. A two-component, solvent-free adhesive with reduced fluidity becomes difficult to apply to the substrate. Moreover, since the solidified polyol component cannot be sufficiently mixed with the polyisocyanate component, the adhesive performance of the two-component, solvent-free adhesive decreases. Such adhesives must be heated to maintain a molten state (a fluid state). In other words, such polyol components do not have good workability. On the other hand, when using a liquid polyol component, heating and melting are unnecessary during use because it is not in a solid state. Furthermore, the fluidity of the two-component solvent-free adhesive is maintained for a relatively long time even after mixing with the polyisocyanate component. However, generally, the polyisocyanate component and the polyol component are stored separately for a long time until use. Therefore, if the liquid macropolyol content in the polyol component is extremely high, it will not solidify for a long time, and the powder in the polyol component tends to settle over time. When using a polyol component with settled powder, it is not possible to improve the appearance of the coating film of the two-component solvent-free adhesive. Specifically, because the powder in the two-component solvent-free adhesive is unevenly distributed, unevenness in the appearance of the coating film is likely to occur. In addition, the adhesive strength may be inferior in the areas of the coating film where the powder is unevenly distributed. Moreover, on an industrial scale, stirring a polyol component with settled powder at the time of use to uniformly disperse the powder in the polyol component is time-consuming and costly. In other words, since it is preferable for the powder to be uniformly dispersed within the polyol component when using the polyol component, it is also preferable for the powder to be uniformly dispersed within the polyol component even during long-term storage. In contrast, the present invention, in particular, includes a macropolyol comprising a liquid macropolyol and a solid macropolyol, with the respective proportions being within a predetermined range. Therefore, after melting the polyol component, it maintains its fluidity for several hours, i.e., during the usage period of the two-component curing adhesive. In other words, the workability of the polyol component can be improved. Furthermore, after melting the polyol component and uniformly dispersing the powder, it loses its fluidity and solidifies during storage. In other words, the polyol component solidifies before the powder settles. Therefore, the powder can remain dispersed within the polyol component even during long-term storage. Moreover, with such a polyol component, it can be used simply by heating and melting the polyol component at the time of use. In other words, powder settling can be suppressed.

[0146] 3. Second Embodiment The above describes in detail the case where the polyol component contains powder, but the polyol component may not contain powder, and only the polyisocyanate component may contain powder. In this case, the polyisocyanate component includes polyisocyanate that is liquid at 25°C, polyisocyanate that is solid at 25°C, and powder.

[0147] A polyisocyanate that is liquid at 25°C is a polyisocyanate that is fluid in an environment at 25°C.

[0148] Examples of polyisocyanates that are liquid at 25°C (hereinafter sometimes simply referred to as liquid polyisocyanates) include the liquid polyisocyanate compounds among the polyisocyanate compounds mentioned above.

[0149] Examples of liquid polyisocyanate compounds include liquid polyisocyanate monomers, liquid polyisocyanate derivatives, and liquid prepolymer compositions.

[0150] Examples of liquid polyisocyanate monomers include pentamethylene diisocyanate (PDI), hexamethylene diisocyanate (HDI), isophorone diisocyanate (IPDI), and methylenebis(cyclohexyl isocyanate) (H 12 Examples include MDI, bis(isocyanatomethyl)cyclohexane (H6XDI), tolylene diisocyanate (TDI), a mixture of 2,4'-isomers of diphenylmethane diisocyanate (MDI), and xylylene diisocyanate (XDI). These can be used individually or in combination of two or more.

[0151] Examples of liquid polyisocyanate derivatives include isocyanurate derivatives of hexamethylene diisocyanate (HDI), isocyanurate derivatives of xylylene diisocyanate (XDI), allophanate derivatives of pentamethylene diisocyanate (PDI), allophanate derivatives of hexamethylene diisocyanate (HDI), allophanate derivatives of tolylene diisocyanate (TDI), allophanate derivatives of xylylene diisocyanate (XDI), biuret derivatives of pentamethylene diisocyanate (PDI), biuret derivatives of hexamethylene diisocyanate (HDI), and pentamethylene diisocyanate ( Examples include oxadiazinetrione derivatives of PDI, oxadiazinetrione derivatives of hexamethylene diisocyanate (HDI), oxadiazinetrione derivatives of xylylene diisocyanate (XDI), carbodiimide derivatives of pentamethylene diisocyanate (PDI), carbodiimide derivatives of hexamethylene diisocyanate (HDI), carbodiimide derivatives of 1,3- or 1,4-tetramethylxylylene diisocyanate or mixtures thereof (TMXDI), carbodiimide derivatives of diphenylmethane diisocyanate (MDI), and polymethylene polyphenyl polyisocyanate (polymeric MDI).

[0152] The liquid prepolymer composition is a composition containing an isocyanate-terminated prepolymer. The isocyanate-terminated prepolymer is a reaction product of a raw material polyisocyanate and a raw material polyol.

[0153] Examples of raw material polyisocyanates include the polyisocyanate monomers and polyisocyanate derivatives mentioned above. The raw material polyisocyanates are appropriately selected so that the prepolymer composition becomes liquid, and can be used alone or in combination of two or more types. Preferably, the raw material polyisocyanates include the liquid polyisocyanate monomers and liquid polyisocyanate derivatives mentioned above.

[0154] Examples of raw material polyols include the high molecular weight polyols and low molecular weight polyols mentioned above. The raw material polyols are appropriately selected so that the prepolymer composition becomes liquid, and can be used alone or in combination of two or more types. Preferably, the raw material polyols include liquid high molecular weight polyols and liquid low molecular weight polyols. Liquid high molecular weight polyols are compounds that are liquid at 25°C selected from the high molecular weight polyols mentioned above. Liquid low molecular weight polyols are compounds that are liquid at 25°C selected from the low molecular weight polyols mentioned above.

[0155] The content ratio of liquid polyisocyanate to the polyisocyanate component is 15% by mass or more, preferably 20% by mass or more, more preferably 30% by mass or more, even more preferably 40% by mass or more, even more preferably 50% by mass or more, particularly preferably 60% by mass or more, and also 90% by mass or less, preferably 85% by mass or less, more preferably 80% by mass or less, even more preferably 75% by mass or less, particularly preferably 70% by mass or less.

[0156] A polyisocyanate that is solid at 25°C is a polyisocyanate that does not have fluidity in an environment at 25°C.

[0157] Examples of polyisocyanates that are solid at 25°C (hereinafter sometimes simply referred to as solid polyisocyanates) include the solid polyisocyanate compounds among the polyisocyanate compounds mentioned above.

[0158] Examples of solid polyisocyanate compounds include solid polyisocyanate monomers, solid polyisocyanate derivatives, and solid prepolymer compositions.

[0159] Examples of solid polyisocyanate monomers include 4,4'-diphenylmethane diisocyanate (MDI), 1,5-naphthalene diisocyanate (NDI), 4,4'-diisocyanato-3,3'-dimethylbiphenyl (TODI), and 1,4'-phenylene diisocyanate (PPDI).

[0160] Examples of solid polyisocyanate derivatives include isocyanurate derivatives of isophorone diisocyanate (IPDI), polyol derivatives of tolylene diisocyanate (TDI), polyol derivatives of xylylene diisocyanate (XDI), and polyol derivatives of isophorone diisocyanate (IPDI). These can be used individually or in combination of two or more.

[0161] The solid prepolymer composition is a composition containing an isocyanate-terminated prepolymer. The isocyanate-terminated prepolymer is a reaction product of a raw material polyisocyanate and a raw material polyol.

[0162] Examples of raw material polyisocyanates include the polyisocyanate monomers and polyisocyanate derivatives mentioned above. The raw material polyisocyanates are appropriately selected so that the prepolymer composition becomes solid, and can be used alone or in combination of two or more types. Preferably, the raw material polyisocyanates include the solid polyisocyanate monomers and solid polyisocyanate derivatives mentioned above.

[0163] Examples of raw material polyols include the high molecular weight polyols and low molecular weight polyols mentioned above. The raw material polyols are appropriately selected so that the prepolymer composition becomes solid, and can be used alone or in combination of two or more types. Preferably, the raw material polyols include solid high molecular weight polyols and solid low molecular weight polyols. Solid high molecular weight polyols are compounds that are solid at 25°C selected from the above high molecular weight polyols. Solid low molecular weight polyols are compounds that are solid at 25°C selected from the above low molecular weight polyols.

[0164] The content ratio of solid polyisocyanate to the polyisocyanate component is 7% by mass or more, preferably 12% by mass or more, more preferably 17% by mass or more, even more preferably 22% by mass or more, particularly preferably 27% by mass or more, and also 82% by mass or less, preferably 77% by mass or less, more preferably 67% by mass or less, even more preferably 57% by mass or less, even more preferably 47% by mass or less, particularly preferably 37% by mass or less.

[0165] Examples of powders include the powders listed above as polyol components.

[0166] The proportion of powder relative to the polyisocyanate component is 0.1% by mass or more, preferably 0.5% by mass or more, more preferably 1% by mass or more, and 10% by mass or less, preferably 5% by mass or less, more preferably 3% by mass or less.

[0167] The above-mentioned two-component, solvent-free curing adhesive contains a polyisocyanate component and a polyol component. The polyisocyanate component includes polyisocyanate that is liquid at 25°C, polyisocyanate that is solid at 25°C, and a powder. The content of liquid polyisocyanate relative to the polyisocyanate component is 15% by mass or more and 90% by mass or less, the content of solid polyisocyanate is 7% by mass or more and 82% by mass or less, and the content of powder is 0.1% by mass or more and 10% by mass or less.

[0168] As a result, similar to the polyol component detailed above, the polyisocyanate component contains both liquid and solid polyisocyanate, and since the proportions of each are within a predetermined range, the polyisocyanate component maintains its fluidity during the usage time of the two-component curing adhesive after melting. In other words, the workability of the polyisocyanate component can be improved. Furthermore, after melting the polyisocyanate component and uniformly dispersing the powder, it loses its fluidity and solidifies during storage. In other words, it is possible to suppress the sedimentation of the powder.

[0169] Furthermore, in a two-component, solvent-free curing adhesive, both the polyisocyanate component and the polyol component may contain powder. In this case, the polyisocyanate component includes liquid polyisocyanate, solid polyisocyanate, and powder, with their respective content ratios within the above range. Similarly, the polyol component includes macropolyol and powder, with their respective content ratios within the above range. Moreover, the macropolyol includes liquid macropolyol and solid macropolyol, with their respective content ratios within the above range. Therefore, when both the polyisocyanate component and the polyol component contain powder, improvements in workability and suppression of powder sedimentation can be achieved for both the polyisocyanate component and the polyol component. [Examples]

[0170] Next, the present invention will be described based on examples and comparative examples, but the present invention is not limited thereto. Unless otherwise specified, "parts" and "%" refer to mass. Furthermore, specific numerical values ​​such as blending ratios (content), physical properties, and parameters used in the following description may be replaced with the corresponding upper limits (numerical values ​​defined as "less than or equal to" or "less than") or lower limits (numerical values ​​defined as "greater than or equal to" or "greater than or equal to" or "greater than or equal to") of the blending ratios (content), physical properties, and parameters described in the "Modes for Carrying Out the Invention" above.

[0171] 1. Preparation of raw materials <Raw materials for polyisocyanate components> (Polyisocyanate as raw material) • D-178NL (an allophanate derivative of 1,6-hexamethylene diisocyanate (HDI), trade name "Takenate D-178NL", manufactured by Mitsui Chemicals, Inc.) • D-177N (a mixture of allophanate derivatives and isocyanurate derivatives of 1,6-hexamethylene diisocyanate (HDI), trade name "Takenate D-177N", manufactured by Mitsui Chemicals, Inc.) • D-165N (a biuret derivative of 1,6-hexamethylene diisocyanate (HDI), trade name "Takenate D-165N", manufactured by Mitsui Chemicals, Inc.) • T-1890 (Isocyanurate derivative of isophorone diisocyanate (IPDI), manufactured by Evonik Japan Co., Ltd.) • Cosmonate PH (4,4'-diphenylmethane diisocyanate (MDI), manufactured by Mitsui Chemicals, Inc.) (Raw material polyol) • Polyester polyol A (number average molecular weight (Mn): 500, manufactured by Mitsui Chemicals, Inc.) Actcol D-1000 (polyoxypropylene diol, average molecular weight (Mn): 1000, manufactured by Mitsui Chemicals, Inc.) • Actcol P-24 (polyoxypropylene diol, average molecular weight (Mn): 2200, manufactured by Mitsui Chemicals, Inc.) • Actcol T-1000D (polyoxypropylene triol, average molecular weight (Mn): 1000, manufactured by Mitsui Chemicals, Inc.) • PTMG1000 (Polytetramethylene ether glycol, average molecular weight (Mn): 1000, manufactured by Mitsubishi Chemical Corporation)

[0172] <Raw materials for polyol components> (Liquid macropolyol) • Liquid polycarbonate 1 (liquid polycarbonate polyol) Commercially available polycarbonate polyol (number average molecular weight (Mn): 800, hydroxyl group equivalent: 400, alcohol composition: 1,4-butanediol 50 mol%, 2-methyl-1,3-propanediol 50 mol%) • Liquid polycarbonate 2 (liquid polycarbonate polyol) Commercially available polycarbonate polyol (number average molecular weight (Mn): 2000, hydroxyl group equivalent: 1000, alcohol composition: 2-methyl-1,3-propanediol 100 mol%) • Liquid polycarbonate 3 (liquid polycarbonate polyol) Commercially available polycarbonate polyol (number average molecular weight (Mn): 500, hydroxyl group equivalent: 250, alcohol composition: 2-methyl-1,3-propanediol 100 mol%) • Liquid polycarbonate 4 (liquid polycarbonate polyol) Commercially available polycarbonate polyol (number average molecular weight (Mn): 800, hydroxyl group equivalent: 400, alcohol composition: 1,5-pentanediol 50 mol%, 1,6-hexanediol 50 mol%) • Liquid polyether 1 (liquid polyether polyol) PTXG 1800 (branched alkyl-modified polytetramethylene ether glycol, number average molecular weight (Mn): 1800, hydroxyl group equivalent: 900, THF-neopentyl glycol copolymer, manufactured by Asahi Kasei Corporation) • Liquid polyester 1 (liquid polyester polyol) 626 parts by mass of adipic acid and 1345 parts by mass of neopentyl glycol were charged into separate reactors, and the esterification reaction was carried out under a nitrogen atmosphere at 160°C to 220°C. Subsequently, a predetermined amount of condensed water was distilled to obtain liquid polyester 1 (polyester polyol, number average molecular weight (Mn): 800, hydroxyl group equivalent: 400). (Solid macropolyols) • Solid polycarbonate 1 (solid polycarbonate polyol) Commercially available polycarbonate polyol (number average molecular weight (Mn): 500, hydroxyl group equivalent: 250, alcohol composition: 1,6-hexanediol 100 mol%) • Solid polycarbonate 2 (solid polycarbonate polyol) Commercially available polycarbonate polyol (number average molecular weight (Mn): 1000, hydroxyl group equivalent: 500, alcohol composition: 1,6-hexanediol 100 mol%) • Solid polyether 1 (solid polyether polyol) PTMG 2000 (Polytetramethylene ether glycol, number average molecular weight (Mn): 2000, hydroxyl group equivalent: 1000, THF polymer, manufactured by Mitsubishi Chemical Corporation) (Low molecular weight polyols) • Dipropylene glycol Trimethylol propane (powder) • Zeolite (commercially available zeolite, average particle size 2.1 μm) ·Acrylic resin (Techpolymer MBX-2H, average particle size 2.5μm, manufactured by Sekisui Plastics Co., Ltd.) (Additives) • KBM-403 (Epoxy group-containing silane coupling agent, 3-glycidoxypropyltrimethoxysilane, silane coupling agent, manufactured by Shin-Etsu Chemical Co., Ltd.) • KBE-903 (amino group-containing silane coupling agent, 3-aminopropyltriethoxysilane, silane coupling agent, manufactured by Shin-Etsu Chemical Co., Ltd.) • OTS (o-toluenesulfonamide, stabilizer) • JPP-100 (Tetraphenyldipropylene glycol diphosphite, antioxidant, manufactured by Johoku Chemical Industry Co., Ltd.)

[0173] 2. Synthesis Examples <Polyisocyanate component> • Synthesis Example 1: Polyisocyanate A 567 parts by mass of D-178NL, 150 parts by mass of D-177N, and 150 parts by mass of T-1890 were charged into a reactor and stirred under a nitrogen stream at 70-80°C until T-1890 (in solid pellet form) dissolved. Then, polyester polyol A was charged and the urethane reaction was carried out. This yielded a prepolymer composition containing an isocyanate group-terminated prepolymer (hereinafter referred to as polyisocyanate A). This was cooled to 60°C and 20 parts by mass of KBM-403 was added. The isocyanate group equivalent of polyisocyanate A was 286, and the isocyanate group concentration was 14.7% by mass. The isocyanate group equivalent and isocyanate group concentration were measured in accordance with JIS K 1603-1 (2007) Method A (the same applies hereinafter).

[0174] • Synthesis Example 2: Polyisocyanate B 136.44 parts by mass of Actcol D-1000, 147.19 parts by mass of Actcol P-24, 107.44 parts by mass of Actcol T-1000D, and 210.34 parts by mass of PTMG1000 were charged into the reactor. Next, under a nitrogen atmosphere, the mixture was bubbling at 110-115°C (dehydration to less than 0.015% moisture content), then cooled to 50°C, and 0.05 parts by mass of OTS, 0.20 parts by mass of JPP-100, and 398.34 parts by mass of Cosmonate PH were added. The urethane reaction was carried out at 77-82°C (equivalent ratio (isocyanate group / active hydrogen group): 2.80). This yielded a prepolymer composition containing an isocyanate group-terminated prepolymer (hereinafter referred to as polyisocyanate B). The isocyanate group equivalent of polyisocyanate B was 488.5, and the isocyanate group concentration was 8.6% by mass.

[0175] • Synthesis Example 3: Polyisocyanate C 704 parts by mass of polyisocyanate B from Synthesis Example 2, 99 parts by mass of D-178NL, and 197 parts by mass of D-165N were mixed under a nitrogen atmosphere at 50-60°C. This yielded a prepolymer composition containing an isocyanate group-terminated prepolymer (hereinafter referred to as polyisocyanate C). The isocyanate group equivalent of polyisocyanate C was 334.7, and the isocyanate group concentration was 12.5% ​​by mass.

[0176] 3. Examples <Polyol components> (Examples 1-21 and Comparative Examples 1-8) According to the parts by mass listed in Tables 1-3, liquid macropolyols, solid macropolyols, and powders were mixed in a disperser at 60°C under a nitrogen atmosphere. This yielded the polyol components of Examples 1-21 and Comparative Examples 1-8.

[0177] (Examples 22-24) According to the parts by mass listed in Table 4, liquid macropolyols, solid macropolyols, low molecular weight polyols, powders, and additives were mixed in a disperser at 60°C under a nitrogen atmosphere. This yielded the polyol components of Examples 22-24.

[0178] <Two-component, solvent-free adhesive> (Examples 25-29) A two-component, solvent-free adhesive was obtained by combining the polyisocyanate components of Synthesis Examples 1 and 3 and the polyol components of Examples 22 to 24 according to the parts by mass listed in Table 5. The equivalent ratio (NCO / OH) listed in Table 5 represents the equivalent ratio of isocyanate groups in the polyisocyanate component to hydroxyl groups in the polyol component.

[0179] 4. Evaluation Method <Liquidity> The polyol components obtained in Examples 1-24 and Comparative Examples 1-8 were immediately transferred to sample bottles and stored at room temperature (25°C and 5°C). The change in fluidity of the polyol components over time was observed at the elapsed times indicated in each table. The results are shown in Tables 1-4. Fluidity was evaluated according to the following criteria. Yes: The liquid moves when the bottle is tilted; it is in a fluid state. Slightly: A state between being fluid and completely waxy; it moves slowly when the bottle is tilted (slightly fluid state). None: Completely waxy, cloudy, and non-fluid.

[0180] <Workability> Based on the fluidity results described above, the workability of the polyol components was evaluated according to the following criteria. The results are shown in Tables 1-4. Evaluation A represents the best workability, with workability decreasing in that order. A: After 6 hours, liquidity is "present" or "slight". B: After 6 hours, liquidity is "none". C: After 4 hours, liquidity is "none". D: After 2 hours, liquidity is "none".

[0181] <Settlement Inhibition> Based on the fluidity results under a 5°C environment, the sedimentation suppression properties of the polyol component powder were evaluated according to the following criteria. The results are shown in Tables 1 to 4. Evaluation A shows the best sedimentation suppression, and the sedimentation suppression decreases in the following order. A: After 1 day, liquidity is "none". B: After 3 days, liquidity is "none". C: After 3 days, liquidity is "very low". D: After 3 days, liquidity is "present".

[0182] <Appearance and adhesive strength> (1) Preparation of laminate composite film A mixture of the polyisocyanate and polyol components of the two-component, solvent-free adhesives obtained in Examples 25-29 was applied to the surface of a polyethylene terephthalate film (thickness 12 μm, E5102, manufactured by Toyobo Co., Ltd.) using a solvent-free laminator (manufactured by Okazaki Machinery Industry Co., Ltd., Non-Sol Laminator TNS-400-200) (coating temperature 80°C, coating amount approximately 1.5 g / m²). 2 The coating speed was 200 m / min. Subsequently, an unoriented polypropylene film (25 μm thick, ML CP WS (manufactured by RM Tohsero Co., Ltd.)) with aluminum vacuum deposition was laminated onto the coated surface to create a laminated composite film. The laminated composite film was then aged at 40°C for 3 days to cure the mixture (two-component solvent-free curing adhesive). (2) Evaluation of appearance The laminated appearance of the laminate composite film obtained as described above was observed and evaluated according to the following criteria. The results are shown in Table 5. A: No air bubbles or / or yuzu peel texture were observed, and the appearance was remarkably good. B: Few air bubbles and / or yuzu peel texture were observed, and the appearance was good. C: Significant bubbles and / or a peel-like texture were observed. (3) Evaluation of adhesive strength The adhesive strength between the polyethylene terephthalate film of the laminated composite film obtained as described above and the unoriented polypropylene film to which aluminum was vacuum-deposited was measured by a T-type peel test at 25°C, with a test piece width of 15 mm and a tensile speed of 300 mm / min. Based on the obtained adhesive strength, the adhesive strength was evaluated according to the following criteria. The results are shown in Table 5. A: The adhesive strength was 0.7 N / 15 mm or higher, and the condition of the laminate composite film after measurement was either interfacial delamination or material failure of the adherend, rather than cohesive failure of the adhesive. B: The adhesive strength was less than 0.7 N / 15 mm, and / or the condition of the laminate composite film after measurement was that of adhesive cohesive failure.

[0183] Based on the results of the above-mentioned evaluation of appearance and adhesive strength, it was confirmed that the above-mentioned two-component, solvent-free curing adhesive is suitable for use as an adhesive.

[0184] [Table 1]

[0185] [Table 2]

[0186] [Table 3]

[0187] [Table 4]

[0188] [Table 5]

Claims

1. This is a two-component, solvent-free adhesive containing a polyisocyanate component and a polyol component. The aforementioned polyol component is Macropolyols and, Contains powder, With respect to the aforementioned polyol component, The macropolyol content is 80% by mass or more. The powder content is 0.1% by mass or more and 10% by mass or less. The aforementioned macropolyol is, A macropolyol that is liquid at 25°C, It contains a macropolyol that is solid at 25°C. For the aforementioned macropolyol, The macropolyol content of the liquid is 15% by mass or more and 93% by mass or less. A two-component, solvent-free adhesive in which the content of the macropolyol in the solid is 7% by mass or more and 85% by mass or less.

2. For the aforementioned macropolyol, The macropolyol content of the liquid is 30% by mass or more and 80% by mass or less. The two-component, solvent-free adhesive according to claim 1, wherein the content of the macropolyol in the solid is 20% by mass or more and 70% by mass or less.

3. The aforementioned liquid macropolyol is a liquid polycarbonate polyol. The two-component, solvent-free curing adhesive according to claim 1, wherein the solid macropolyol is a solid polycarbonate polyol.

4. The two-component, solvent-free adhesive according to claim 1, wherein the average particle size of the powder is 1.0 μm or more and 5.0 μm or less.

5. A polyol component used in the two-component, solvent-free adhesive described in claim 1, The aforementioned polyol component is Macropolyols and, Contains powder, With respect to the aforementioned polyol component, The macropolyol content is 80% by mass or more. The powder content is 0.1% by mass or more and 10% by mass or less. The aforementioned macropolyol is, A macropolyol that is liquid at 25°C, It contains a macropolyol that is solid at 25°C. For the aforementioned macropolyol, The macropolyol content of the liquid is 15% by mass or more and 93% by mass or less. A polyol component wherein the content of the macropolyol in the solid is 7% by mass or more and 85% by mass or less.

6. This is a two-component, solvent-free adhesive containing a polyisocyanate component and a polyol component. The aforementioned polyisocyanate component is Polyisocyanate is liquid at 25°C, Polyisocyanate is solid at 25°C, Contains powder, With respect to the aforementioned polyisocyanate component, The polyisocyanate content of the aforementioned liquid is 15% by mass or more and 90% by mass or less. The polyisocyanate content of the solid is 7% by mass or more and 82% by mass or less. A two-component, solvent-free adhesive in which the powder content is 0.1% by mass or more and 10% by mass or less.

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