Polyisocyanate composition and blocked isocyanate composition

Abstract

To provide a polyisocyanate composition, and a block isocyanate composition excellent in adhesion, impact resistance, and chemical resistance.SOLUTION: A polyisocyanate composition is a reaction product of raw material constituents including a polyisocyanate constituent including aliphatic diisocyanate, and xylylene diisocyanate, or a modified compound thereof, and a polyol constituent including polycaprolactone polyol. The polyisocyanate composition has an isocyanate group at a molecular terminal. A ratio of a mole number of the aliphatic diisocyanate to a mole number of the xylylene diisocyanate, or the modified compound thereof (a mole number of the aliphatic diisocyanate / a mole number of the xylylene diisocyanate, or the modified compound thereof) is 2.0 or more and 12.0 or less.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to a polyisocyanate composition and a block copolymer. Qui More specifically, the present invention relates to a polyisocyanate composition and a blocked polyisocyanate composition in which an isocyanate group is blocked with a blocking agent. Qui The present invention relates to a socyanate composition. [Background technology]

[0002] Polyurethane resins are usually produced by the reaction of polyisocyanates with active hydrogen group-containing compounds. Polyurethane resins are widely used in various industrial fields, for example, as coating materials, adhesive materials, pressure-sensitive adhesive materials, and elastomers. In detail, polyurethane resins can be applied to a substrate to form a coating film, thereby imparting various physical properties to the substrate.

[0003] As a polyisocyanate used in the production of polyurethane resin, a polyisocyanate composition obtained by reacting 1,6-hexane diisocyanate (HDI) with polycaprolactone polyol has been proposed (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2020-139017 A Summary of the Invention [Problem to be solved by the invention]

[0005] In recent years, the shapes of substrates for automotive and electrical applications have tended to become more complex. When the shapes become more complex, the coating film formed from the polyurethane resin is required to have adhesion to conform to the complex shapes of the substrates.

[0006] Furthermore, coating films formed from polyurethane resins are required to have impact resistance and chemical resistance.

[0007] The present invention relates to a polyisocyanate composition and a block copolymer having excellent adhesion, impact resistance and chemical resistance. Qui The object of the present invention is to provide a socyanate composition. [Means for solving the problem]

[0008] The present invention [1] is a polyisocyanate composition which is a reaction product of raw material components including an aliphatic diisocyanate, a polyisocyanate component including xylylene diisocyanate or a modified product thereof, and a polyol component including a polycaprolactone polyol, and which has isocyanate groups at molecular terminals, and in which the ratio of the number of moles of the aliphatic diisocyanate to the number of moles of the xylylene diisocyanate or a modified product thereof (number of moles of aliphatic diisocyanate / number of moles of xylylene diisocyanate or a modified product thereof) is 2.0 or more and 12.0 or less.

[0009] The present invention [2] includes the polyisocyanate composition according to the above [1], in which the polycaprolactone polyol has a number average molecular weight of 250 or more and less than 2,000.

[0010] The present invention [3] includes the polyisocyanate composition according to the above [1] or [2], in which the raw material components further include an isocyanate silane, and the mixing ratio of the isocyanate silane is 0.5 parts by mass or more and 10 parts by mass or less per 100 parts by mass of the polyisocyanate component.

[0011] The present invention [4] provides the polyisocyanate composition according to any one of the above [1] to [3], wherein the isocyanate group is blocked with a blocking agent. Qui Contains a socyanate composition. Effect of the Invention

[0012] The polyisocyanate composition of the present invention is a reaction product of raw material components including a polyisocyanate component containing an aliphatic diisocyanate and xylylene diisocyanate or its modified product, and a polyol component containing a polycaprolactone polyol. The ratio of the mole number of the aliphatic diisocyanate to the mole number of the xylylene diisocyanate or its modified product (the mole number of the aliphatic diisocyanate / the mole number of the xylylene diisocyanate or its modified product) is within a predetermined range. Therefore, according to this polyisocyanate composition, a polyurethane resin having excellent adhesion, impact resistance, and chemical resistance can be produced.

[0013] The block diagram of the present invention Qui In the polyisocyanate composition of the present invention, the isocyanate group is blocked with a blocking agent, and therefore the isocyanate composition has a long pot life and excellent processability. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] The polyisocyanate composition of the present invention is a reaction product of raw material components including a polyisocyanate component containing an aliphatic diisocyanate, and xylylene diisocyanate or a modified product thereof, and a polyol component containing a polycaprolactone polyol.

[0015] <Polyisocyanate component> The polyisocyanate component includes an aliphatic diisocyanate, and xylylene diisocyanate or a modified product thereof.

[0016] Examples of the aliphatic diisocyanate include hexamethylene diisocyanate (hexane diisocyanate) (HDI), pentamethylene diisocyanate (pentane diisocyanate) (PDI), tetramethylene diisocyanate, trimethylene diisocyanate, 1,2-, 2,3- or 1,3-butylene diisocyanate, and 2,4,4- or 2,2,4-trimethylhexamethylene diisocyanate. Hexamethylene diisocyanate and pentamethylene diisocyanate are preferred, and hexamethylene diisocyanate is more preferred.

[0017] The aliphatic diisocyanates can be used alone or in combination of two or more kinds.

[0018] The polyisocyanate component may contain a modified aliphatic diisocyanate together with the aliphatic diisocyanate. The polyisocyanate component preferably does not contain a modified aliphatic diisocyanate.

[0019] The modified aliphatic diisocyanate may be the same as the modified xylylene diisocyanate described below.

[0020] Xylylene diisocyanate includes structural isomers 1,2-xylylene diisocyanate (o-XDI), 1,3-xylylene diisocyanate (m-XDI), and 1,4-xylylene diisocyanate (p-XDI). The structural isomers of xylylene diisocyanate can be used alone or in combination of two or more types.

[0021] The xylylene diisocyanate preferably includes 1,3-xylylene diisocyanate. That is, the xylylene diisocyanate preferably includes 1,3-xylylene diisocyanate, and more preferably consists of 1,3-xylylene diisocyanate.

[0022] Examples of the modified xylylene diisocyanate include the above-mentioned multimers of xylylene diisocyanate (e.g., dimers, trimers (e.g., isocyanurate modified products, iminooxadiazinedione modified products), pentamers, heptamers, etc.), allophanate modified products (e.g., allophanate modified products produced by the reaction of the above-mentioned xylylene diisocyanate with a monohydric alcohol or a dihydric alcohol), polyol modified products (e.g., polyol modified products (alcohol adducts) produced by the reaction of the above-mentioned xylylene diisocyanate with a trihydric alcohol (e.g., trimethylolpropane)), biurea modified products, etc. Examples of the modified xylylene diisocyanate include a biuret modified product (e.g., the biuret modified product produced by the reaction of the above-mentioned xylylene diisocyanate with water or amines), a urea modified product (e.g., the urea modified product produced by the reaction of the above-mentioned xylylene diisocyanate with a diamine), an oxadiazinetrione modified product (e.g., the oxadiazinetrione modified product produced by the reaction of the above-mentioned xylylene diisocyanate with carbon dioxide), a carbodiimide modified product (e.g., the carbodiimide modified product produced by the above-mentioned decarboxylation condensation reaction of the xylylene diisocyanate), a uretdione modified product, and a uretonimine modified product. As the modified product of the xylylene diisocyanate, an allophanate modified product of the xylylene diisocyanate is preferably used.

[0023] The allophanate modified product of xylylene diisocyanate can be obtained by a known method. For example, the allophanate modified product of xylylene diisocyanate can be obtained by subjecting xylylene diisocyanate and a monool (e.g., isobutanol) to a urethane reaction in the presence of a known urethane catalyst, and then subjecting the resulting mixture to an allophanate reaction in the presence of a known allophanate catalyst.

[0024] The modified xylylene diisocyanate may be used alone or in combination of two or more kinds.

[0025] In addition, in the polyisocyanate component, the ratio of the number of moles of aliphatic diisocyanate to the number of moles of xylylene diisocyanate or its modified product (number of moles of aliphatic diisocyanate / number of moles of xylylene diisocyanate or its modified product) is 2.0 or more, preferably 5.0 or more, more preferably 8.0 or more, and is 12.0 or less, preferably 11.0 or less.

[0026] When the above ratio is equal to or greater than the above lower limit, a polyurethane resin excellent in adhesion and impact resistance (specifically, breaking elongation and impact absorption) can be produced.

[0027] On the other hand, if the content is less than the above lower limit, the adhesion and impact resistance (specifically, breaking elongation and impact absorption properties) of the polyurethane resin obtained by using this polyisocyanate composition will decrease.

[0028] When the ratio is equal to or less than the upper limit, a polyurethane resin having excellent impact resistance (specifically, breaking strength and impact absorption) and chemical resistance can be produced.

[0029] Furthermore, if the ratio exceeds the upper limit, the impact resistance (specifically, breaking strength and impact absorption) and chemical resistance of the polyurethane resin obtained by using this polyisocyanate composition will decrease.

[0030] As described above, the polyisocyanate component contains an aliphatic diisocyanate, and xylylene diisocyanate or a modified product thereof. Preferably, from the viewpoints of impact resistance (specifically, breaking elongation) and adhesion, the polyisocyanate component does not contain a modified product of xylylene diisocyanate, and contains an aliphatic diisocyanate and xylylene diisocyanate.

[0031] The polyisocyanate component may also contain other polyisocyanates and / or modified versions of the polyisocyanates.

[0032] Examples of other polyisocyanates include aromatic polyisocyanates, araliphatic polyisocyanates (excluding xylylene diisocyanate; the same applies below), and alicyclic polyisocyanates.

[0033] Examples of aromatic polyisocyanates include aromatic diisocyanates. Examples of aromatic diisocyanates include 4,4'-, 2,4'- or 2,2'-diphenylmethane diisocyanate or mixtures thereof (MDI), 2,4- or 2,6-tolylene diisocyanate or mixtures thereof (TDI), o-tolidine diisocyanate, 1,5-naphthalene diisocyanate (NDI), m- or p-phenylene diisocyanate or mixtures thereof, 4,4'-diphenyl diisocyanate, and 4,4'-diphenyl ether diisocyanate.

[0034] Examples of the araliphatic polyisocyanate include araliphatic diisocyanates, such as 1,3- or 1,4-tetramethylxylylene diisocyanate or a mixture thereof (TMXDI), and ω,ω′-diisocyanato-1,4-diethylbenzene.

[0035] Examples of alicyclic polyisocyanates include alicyclic diisocyanates. Examples of alicyclic diisocyanates include 3-isocyanatomethyl-3,5,5-trimethylcyclohexyl isocyanate (isophorone diisocyanate, IPDI), 4,4'-, 2,4'- or 2,2'-methylenebis(cyclohexyl isocyanate) or mixtures thereof (H 12MDI), 1,3- or 1,4-bis(isocyanatomethyl)cyclohexane or mixtures thereof (H6XDI), bis(isocyanatomethyl)norbornane (NBDI), 1,3-cyclopentene diisocyanate, 1,4-cyclohexane diisocyanate, 1,3-cyclohexane diisocyanate, methyl-2,4-cyclohexane diisocyanate, and methyl-2,6-cyclohexane diisocyanate.

[0036] Examples of the modified polyisocyanates include the modified polyisocyanates listed above as the modified xylylene diisocyanate.

[0037] The polyisocyanate component preferably does not contain other polyisocyanates and / or modified products of the polyisocyanates, and is composed of an aliphatic diisocyanate and xylylene diisocyanate or a modified product thereof.

[0038] <Polyol component> The polyol component includes a polycaprolactone polyol.

[0039] Polycaprolactone polyols are derived from ε-caprolactone.

[0040] Specifically, polycaprolactone polyol can be obtained by ring-opening polymerization of ε-caprolactone using a low molecular weight polyol (preferably a dihydric alcohol) described later as an initiator. The ring-opening polymerization is carried out by a known method.

[0041] The number average molecular weight of the polycaprolactone polyol (number average molecular weight measured by GPC using standard polystyrene as a calibration curve) is, for example, 200 or more, preferably 250 or more, more preferably 400 or more, from the viewpoints of impact resistance (more specifically, breaking elongation) and adhesion, and for example, 2500 or less, preferably less than 2000, more preferably 1000 or less, even more preferably 750 or less, and particularly preferably 600 or less, from the viewpoints of impact resistance (more specifically, breaking strength and impact absorbency) and chemical resistance.

[0042] The number of functional groups of the polycaprolactone polyol is, for example, 2 or more and, for example, 4 or less, preferably 3 or less. Furthermore, the number of functional groups of the polycaprolactone polyol is more preferably 3.

[0043] The polyol component may also include other polyols.

[0044] Examples of the other polyols include high molecular weight polyols (excluding polycaprolactone polyols; the same applies below) and low molecular weight polyols.

[0045] The high molecular weight polyol is a compound having two or more hydroxyl groups and a number average molecular weight of 400 to 10,000, preferably 500 to 5,000. Examples of the high molecular weight polyol include polyether polyol, polyester polyol (excluding polycaprolactone polyol; the same applies below), polycarbonate polyol, polyurethane polyol, epoxy polyol, polyolefin polyol, acrylic polyol, silicone polyol, fluorine polyol, and vinyl monomer modified polyol.

[0046] The high molecular weight polyols can be used alone or in combination of two or more kinds.

[0047] The low molecular weight polyol is a compound having two or more hydroxyl groups and a number average molecular weight of 40 or more and less than 400. Examples of the low molecular weight polyol include dihydric alcohol, trihydric alcohol, tetrahydric alcohol, pentahydric alcohol, hexahydric alcohol, heptahydric alcohol, and octahydric alcohol. Examples of the dihydric alcohol include ethylene glycol, propylene glycol, 1,3-propanediol, 1,4-butylene glycol, 1,5-pentanediol, 1,6-hexanediol, neopentyl glycol, cyclohexanediol, hydrogenated bisphenol A, bisphenol A, diethylene glycol, and triethylene glycol. Examples of the trihydric alcohol include glycerin, trimethylolpropane, and triisopropanolamine. Examples of the tetrahydric alcohol include tetramethylolmethane (pentaerythritol) and diglycerin. Examples of the pentahydric alcohol include xylitol. Examples of hexahydric alcohols include sorbitol, mannitol, allitol, iditol, dulcitol, altritol, inositol, and dipentaerythritol. Examples of heptahydric alcohols include perseitol. Examples of octahydric alcohols include sucrose.

[0048] The low molecular weight polyols can be used alone or in combination of two or more kinds.

[0049] The polyol component preferably does not contain any other polyol components and consists of polycaprolactone polyol.

[0050] <Isocyanate silane> The raw material component preferably contains isocyanate silane from the viewpoint of achieving both adhesion, impact resistance, and chemical resistance. That is, the raw material component preferably contains a polyisocyanate component, a polyol component, and isocyanate silane, and more preferably consists of a polyisocyanate component, a polyol component, and isocyanate silane.

[0051] Examples of the isocyanate silane include 3-isocyanatopropyltrimethoxysilane and 3-isocyanatopropyltriethoxysilane, preferably 3-isocyanatopropyltriethoxysilane.

[0052] The mixing ratio of the isocyanate silane is, for example, 0.2 parts by mass or more, preferably, from the viewpoint of adhesion, 0.5 parts by mass or more, more preferably 1.0 part by mass or more, even more preferably 3.0 parts by mass or more, and for example, 15 parts by mass or less, preferably, from the viewpoint of impact resistance (more specifically, breaking strength, breaking elongation, and impact absorbency) and chemical resistance, 10 parts by mass or less, more preferably 7 parts by mass or less, relative to 100 parts by mass of the polyisocyanate component.

[0053] The isocyanate silanes can be used alone or in combination of two or more kinds.

[0054] <Polyisocyanate composition> The polyisocyanate composition is obtained by reacting raw material components. More specifically, the polyisocyanate composition is obtained by reacting a polyisocyanate component, a polyol component, and an isocyanate silane that is mixed as required.

[0055] The reaction is carried out by a known polymerization method, such as bulk polymerization or solution polymerization, and preferably, from the viewpoints of reactivity and viscosity adjustment, solution polymerization.

[0056] In the solution polymerization, for example, the above-mentioned raw material components are mixed in an organic solvent under a nitrogen atmosphere and reacted.

[0057] In the above reaction, the equivalent ratio of the isocyanate groups in the polyisocyanate component to the hydroxyl groups in the polyol component (isocyanate groups / hydroxyl groups) is, for example, greater than 1, for example, 1.2 or more, preferably 1.3 or more, and for example, 3.0 or less, preferably 2.5 or less.

[0058] As for reaction conditions, the reaction temperature is, for example, 40° C. or more, preferably 70° C. or more, and for example, 130° C. or less, preferably 110° C. or less. The reaction time is, for example, 1 hour or more, and for example, 20 hours or less, preferably 10 hours or less.

[0059] The organic solvent is selected from solvents that are inactive to isocyanate groups. Examples of the organic solvent include acetone, methyl ethyl ketone, ethyl acetate, tetrahydrofuran, acetonitrile, and N-methylpyrrolidone. The blending ratio of the organic solvent is not particularly limited and is appropriately set according to the purpose and application. The organic solvent can be used alone or in combination of two or more kinds.

[0060] In addition, in the above reaction, a reaction catalyst can be added as necessary. Examples of the reaction catalyst include amine-based catalysts, tin-based catalysts (stannous octylate), and lead-based catalysts, and preferably tin-based catalysts (stannous octylate). The mixing ratio of the reaction catalyst is not particularly limited and is appropriately set according to the purpose and application. The reaction catalyst can be used alone or in combination of two or more kinds.

[0061] This produces a polyisocyanate composition which is a reaction product of the raw material components. When the raw material components are reacted by solution polymerization, the polyisocyanate composition is obtained as a reaction liquid (a solution of the polyisocyanate composition) containing the polyisocyanate composition and an organic solvent. In such a case, the solid content concentration is, for example, 1% by mass or more, preferably 20% by mass or more, more preferably 50% by mass or more, and, for example, 95% by mass or less, preferably 70% by mass or less.

[0062] Furthermore, the unreacted polyisocyanate component can be removed from the resulting reaction product by a known method such as distillation or extraction.

[0063] The polyisocyanate composition has an isocyanate group at a molecular end. Specifically, the polyisocyanate composition has at least one (preferably, a plurality, more preferably, three) free isocyanate group at a molecular end. The content of the isocyanate group (isocyanate group content calculated as solid content excluding organic solvent) is, for example, 1.0 mass% or more, preferably 2.0 mass% or more, and, for example, 15 mass% or less, preferably 10 mass% or less.

[0064] The polyisocyanate composition is a reaction product of raw material components including a polyisocyanate component containing an aliphatic diisocyanate and xylylene diisocyanate or a modified product thereof, and a polyol component containing a polycaprolactone polyol. The ratio of the moles of the aliphatic diisocyanate to the moles of the xylylene diisocyanate or a modified product thereof (the moles of the aliphatic diisocyanate / the moles of the xylylene diisocyanate or a modified product thereof) is within a predetermined range. Therefore, this polyisocyanate composition can produce a polyurethane resin having excellent adhesion, impact resistance, and chemical resistance. In particular, since the polyisocyanate composition has excellent adhesion, even if the shape of the substrate (described later) is complicated, the cured film of the polyurethane resin obtained using this polyisocyanate composition can follow the shape of the substrate (described later) and achieve good adhesion.

[0065] This polyisocyanate composition is suitable for use in producing polyurethane resins, such as two-component curing polyurethanes.

[0066] In two-component curing polyurethane, the curing agent and the base component are each prepared as separate packages, and they are mixed at the time of use to form a polyurethane resin (cured film).

[0067] In the production of a two-component curing polyurethane, a polyisocyanate composition is used as a curing agent.

[0068] If necessary, the curing agent is dissolved in the above-mentioned organic solvent.

[0069] The base agent contains an active hydrogen group-containing compound. Examples of the active hydrogen group-containing compound include a hydroxyl group-containing compound, a mercapto group-containing compound, and an amino group-containing compound, and preferably a hydroxyl group-containing compound.

[0070] Examples of the hydroxyl group-containing compound include the low molecular weight polyols and the high molecular weight polyols described above. The hydroxyl group-containing compound is preferably a high molecular weight polyol, more preferably a polyester polyol.

[0071] The base material may be dissolved in the above-mentioned organic solvent, if necessary.

[0072] The two-component curing polyurethane is obtained by blending the curing agent and the base component at the time of use, and mixing and stirring them.

[0073] Specifically, first, the base agent and the curing agent are prepared, and immediately before use, the base agent and the curing agent are mixed to prepare a two-component curing polyurethane resin (paint), and the two-component curing polyurethane resin is applied to the substrate.

[0074] The blending ratio of the base agent and the curing agent is such that the equivalent ratio (isocyanate group / hydroxyl group) of the isocyanate group in the curing agent (polyisocyanate composition) to the active hydrogen group in the base agent (active hydrogen group-containing compound) is, for example, 0.8 or more, preferably 0.9 or more, and for example, 1.2 or less, preferably 1.1 or less.

[0075] The mixture of the base agent and the curing agent is applied to the substrate by, for example, spray coating, air spray coating, brush coating, dipping, roll coating, flow coating, dry lamination, wet lamination, or direct coating.

[0076] The substrate to be coated is not particularly limited, and examples thereof include various building materials (for example, civil engineering materials such as FRP and steel materials).

[0077] The mixture of the base resin and the curing agent is then dried and cured to obtain a polyurethane resin (cured film).

[0078] This polyurethane resin is obtained by using the above polyisocyanate composition, and therefore has excellent adhesion, impact resistance and chemical resistance.

[0079] <Block Qui Socyanate Composition> Block Qui The isocyanate composition is a reaction product of a polyisocyanate composition and a blocking agent, that is, in the reaction product, the isocyanate groups of the polyisocyanate composition are blocked by the blocking agent.

[0080] The blocking agent has an active group capable of reacting with an isocyanate group. The blocking agent reacts with the free isocyanate group of the polyisocyanate composition to form a latent isocyanate group. Qui The isocyanate composition contains latent isocyanate groups that are blocked with a blocking agent.

[0081] Examples of the blocking agent include the first and second blocking agents described in JP 2017-82208 A. Specifically, the blocking agent includes guanidine compounds, imidazole compounds, alcohol compounds, phenol compounds, active methylene compounds, amine compounds, imine compounds, oxime compounds, carbamic acid compounds, urea compounds, acid amide (lactam) compounds, acid imide compounds, triazole compounds, pyrazole compounds, mercaptan compounds, bisulfites, imidazoline compounds, and pyrimidine compounds, and preferably pyrazole compounds.

[0082] Examples of pyrazole compounds include pyrazole, 3,5-dimethylpyrazole, 3,5-diisopropylpyrazole, 3,5-diphenylpyrazole, 3,5-di-t-butylpyrazole, 3-methylpyrazole, 4-benzyl-3,5-dimethylpyrazole, 4-nitro-3,5-dimethylpyrazole, 4-bromo-3,5-dimethylpyrazole, and 3-methyl-5-phenylpyrazole, and preferably 3,5-dimethylpyrazole.

[0083] The blocking agents can be used alone or in combination of two or more kinds.

[0084] And Blo Qui The isocyanate composition can be obtained by reacting a polyisocyanate composition with a blocking agent.

[0085] The above reaction is carried out, for example, under a nitrogen atmosphere.

[0086] The reaction may be carried out in the absence of a solvent or in the presence of a solvent. Examples of the solvent include the organic solvents described above. When the polyisocyanate composition is produced by solution polymerization, the organic solvent used in the solution polymerization may be used as it is.

[0087] In the above reaction, the equivalent ratio of the active groups capable of reacting with the isocyanate groups in the blocking agent to the isocyanate groups in the polyisocyanate composition (active groups / isocyanate groups) is, for example, 0.2 or more, preferably 0.5 or more, more preferably 0.9 or more, and for example, 1.5 or less, preferably 1.2 or less, more preferably 1.1 or less.

[0088] As for reaction conditions, the reaction temperature is, for example, 20° C. or more, preferably 30° C. or more, and, for example, 100° C. or less, preferably 70° C. or less. The reaction time is, for example, 0.5 hours or more, and, for example, 6 hours or less, preferably 3 hours or less.

[0089] The completion of the reaction can be determined by, for example, infrared spectroscopy or measurement of amine equivalent, and confirming disappearance or reduction of isocyanate groups.

[0090] This allows the block Qui A socyanate composition is obtained.

[0091] Block Qui When the socyanate composition is dissolved in an organic solvent, the solids concentration is, for example, 1 mass% or more, preferably 20 mass% or more, more preferably 50 mass% or more, and for example, 95 mass% or less, preferably 70 mass% or less.

[0092] Block Qui The isocyanate composition is the polyisocyanate composition in which the isocyanate groups are blocked with a blocking agent, and therefore has a long pot life and excellent processability.

[0093] This blocked polyisocyanate composition is suitable for use in producing polyurethane resins, such as one-component curing polyurethanes.

[0094] The one-component curing polyurethane is Qui The socyanate composition (curing agent) and the above-mentioned base agent are mixed in advance. When used, the block is formed by, for example, heating. Qui The blocking agent in the socyanate composition is dissociated and the blocking agent is removed. Qui The regenerated isocyanate group of the isocyanate composition is reacted with the active hydrogen group of the main component (active hydrogen group-containing compound) to produce a polyurethane resin.

[0095] The polyurethane resin, the polyisocyanate composition, and the block copolymer are QuiThe isocyanate composition can be suitably used in various industrial fields. Specifically, the polyurethane resin and the polyisocyanate composition can be suitably used in, for example, paints.

[0096] Specific examples of paints include paints for plastics, paints for automotive exteriors, paints for automotive interiors, paints for electrical and electronic materials, paints for optical materials (lenses, etc.), paints for building materials, glass coating paints, woodworking paints, film coating paints, ink paints, paints for artificial leather (coating agents), and paints for cans (coating agents).

[0097] Examples of the plastic paints include paints for housings (such as mobile phones, smartphones, personal computers, and tablets), paints for automobile parts (such as automobile interior materials and headlamps), paints for household electrical appliances, paints for robot materials, paints for furniture, paints for stationery, paints for eyewear materials (such as lenses), paints for sports components (such as golf balls), paints for bands (such as watch bands), and paints (surface coating agents) for the optical lenses of electronic devices.

[0098] Examples of the above-mentioned paints for exterior use in automobiles include paints for new cars, paints for automobile repairs, and paints for exterior parts (aluminum wheels, bumpers).

[0099] Examples of the film coating paint include paints for optical components (optical films, optical sheets, etc.), optical coating materials, paints for fibers, paints for electronic and electrical materials, paints for food packaging, paints for medical films, paints for cosmetic packaging, paints for decorative films, and paints for release films. EXAMPLES

[0100] Specific numerical values ​​of the blending ratio (content ratio), physical property values, parameters, etc. used in the following description can be replaced with the upper limit values ​​(numerical values ​​defined as "not more than" or "less than") or lower limit values ​​(numerical values ​​defined as "not less than" or "exceeding") of the corresponding blending ratio (content ratio), physical property values, parameters, etc. described in the above "Form for carrying out the invention." In addition, unless otherwise specified in the following description, "parts" and "%" are based on mass.

[0101] 1. Synthesis of allophanate-modified 1,3-xylylene diisocyanate (XDI) Synthesis Example 1 In a 1-liter four-neck flask equipped with a stirrer, a thermometer, a condenser, and a nitrogen gas inlet tube, 100 parts by mass of XDI, 15.8 parts by mass of isobutanol (IBA) (isocyanate group / hydroxyl group=5), 0.06 parts by mass of tris(2-ethylhexyl)phosphite (antioxidant), and 0.06 parts by mass of pentaerythritol tetrakis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate] (antioxidant) were charged under a nitrogen atmosphere. Then, a urethane reaction was carried out at 75°C for 3.5 hours. As a result, a reaction liquid containing a urethane reaction product was obtained.

[0102] Next, 0.06 parts by mass of XK-628 (trade name, manufactured by Kusumoto Chemicals, bismuth carboxylate, bismuth content 31% by mass) was added as an allophanate catalyst to the reaction liquid containing the urethane reaction product. Then, the allophanate reaction was carried out at 90°C for 11 hours, and after it was confirmed that the conversion of the urethane bond to an allophanate bond was almost completed (specifically, after the IR ratio of the urethane group / allophanate group became 0.1 or less), 0.10 parts by mass of orthotoluenesulfonamide (reaction terminator) was added to terminate the allophanate reaction.

[0103] The unreacted isobutanol and XDI were distilled off (removed) from the resulting reaction solution using a thin-film distillation apparatus (degree of vacuum: 0.05 kPa, temperature: 150° C.), thereby obtaining an allophanate-modified product of XDI.

[0104] 2. Polyisocyanate composition and block Qui Preparation of socyanate compositions Examples 1 to 5, Examples 7 to 15, Comparative Example 1, and Comparative Example 2 <Production of polyisocyanate composition> According to the descriptions in Tables 1 to 3, an aliphatic diisocyanate and a xylylene diisocyanate or a modified product thereof were mixed to prepare a polyisocyanate component.

[0105] Next, the raw material components were mixed in a four-neck flask equipped with a stirrer, a thermometer, a reflux tube, and a nitrogen inlet tube. Specifically, 100 parts by mass of the polyisocyanate component, the polyol component (polycaprolactone polyol) shown in Tables 1 to 3, isocyanate silane (3-isocyanatopropyltriethoxysilane, product name KBE9007N manufactured by Shin-Etsu Chemical Co., Ltd.), and 100 parts by mass of butyl acetate were mixed.

[0106] The polycaprolactone polyol was blended so that the equivalent ratio (isocyanate group / hydroxyl group) of the isocyanate group in the polyisocyanate component to the hydroxyl group in the polyol component (polycaprolactone polyol) was 2.

[0107] The mixing ratio of the isocyanate silane was in accordance with Tables 1 to 3.

[0108] Next, the raw material components were reacted at 90° C. for 3 hours while stirring, 0.01 parts by mass of stannous octoate (product name Stanoct, manufactured by Mitsubishi Chemical Corporation) was added, and the reaction was carried out at 90° C. for 1 hour, and when the increase in conversion rate stopped (isocyanate and polyol had reacted in the theoretical amounts based on the amounts charged), the mixture was cooled to 40° C. This produced a polyisocyanate composition (reaction liquid).

[0109] <Block Qui Production of socyanate composition> Into the four-neck flask, 3,5-dimethylpyrazole (manufactured by Japan Finechem Co., Ltd., product name: DMP) was further added as a blocking agent.

[0110] The blocking agent was mixed so that the equivalent ratio of active groups capable of reacting with isocyanate groups in the blocking agent to the isocyanate groups in the polyisocyanate composition (active groups / isocyanate groups) was 1.02.

[0111] The polyisocyanate composition and the blocking agent were then reacted at 40 to 60°C for 1 to 2 hours. The reaction was stopped when the amine equivalent reached 20,000 or more, and then butyl acetate was added to the mixture so that the solid concentration became 60%. Qui A socyanate composition (reaction liquid) was obtained.

[0112] Example 6 According to the description in Table 1, a polyisocyanate composition (reaction liquid) was obtained in the same manner as in Example 1. However, in Example 6, Qui No socyanate compositions were prepared.

[0113] Comparative Example 3 Into a four-neck flask equipped with a stirrer, a thermometer, a reflux condenser, and a nitrogen inlet tube, 100 parts by mass of hexamethylene diisocyanate (HDI) and polycaprolactone polyol (manufactured by Daicel Corporation, product name Plaxel 305, molecular weight 550) were mixed.

[0114] The polycaprolactone polyol was blended so that the equivalent ratio of the isocyanate groups in the HDI to the hydroxyl groups in the polycaprolactone polyol (isocyanate groups / hydroxyl groups) was 12.

[0115] Next, HDI and polycaprolactone polyol were reacted with stirring at 90°C for 3 hours, and 0.01 parts by mass of stannous octoate (manufactured by Mitsubishi Chemical Corporation, product name Stannoct) was added and reacted at 90°C for 1 hour.When the conversion rate stopped increasing (the isocyanate and polyol had reacted in theoretical amounts based on the amounts added), the mixture was cooled to 40°C.

[0116] Next, unreacted HDI in the reaction solution was removed using a glass thin-film evaporator at 150° C. and 50 Pa abs, and the reaction solution was diluted with butyl acetate to a solid content concentration of 64%. This gave a polyisocyanate composition (reaction solution).

[0117] Comparative Example 4 Into a four-neck flask equipped with a stirrer, a thermometer, a reflux tube, and a nitrogen inlet tube, 100 parts by mass of hexamethylene diisocyanate isocyanurate (HDI nurate) and polycaprolactone polyol (manufactured by Daicel Corporation, product name Plaxel 220, molecular weight 2000) were mixed.

[0118] The polycaprolactone polyol was blended so that the equivalent ratio of the isocyanate groups in the HDI nurate to the hydroxyl groups in the polycaprolactone polyol (isocyanate groups / hydroxyl groups) was 9.

[0119] Next, the mixture was reacted at 90°C for 3 hours while stirring, 0.01 parts by mass of stannous octylate (product name: Stanoct, manufactured by Mitsubishi Chemical Corporation) was added, and the mixture was reacted at 90°C for 1 hour. When a predetermined conversion rate was reached, the mixture was cooled to 40°C and diluted with butyl acetate to a solid concentration of 64%. This produced a polyisocyanate composition (reaction liquid).

[0120] 3. Evaluation <Creating a cured polyurethane resin film> Block QuiThe isocyanate compositions (Examples 1 to 5, Examples 7 to 15, Comparative Examples 1 and 2) or the polyisocyanate compositions (Example 6, Comparative Examples 3 and 4) were mixed with a polyester polyol (Takelac U-25 (product name), manufactured by Mitsui Chemicals, hydroxyl value: 135 mg KOH / g, solid content concentration 75%) to obtain a blocking agent for the hydroxyl groups of the polyester polyol. Qui The isocyanate composition or polyisocyanate composition was mixed so that the ratio of isocyanate groups (isocyanate groups / hydroxyl groups) was 1, and mixed with thinner (a 1:1:1 mixture of ethyl acetate, butyl acetate, and propylene glycol monomethyl ether acetate) at 23°C for 5 minutes to a solids concentration of 50%. The mixture was then ultrasonicated for 10 minutes to degas the mixture, yielding a mixed liquid.

[0121] The resulting mixture was then applied to a substrate for each evaluation (described below) using a 4 mil applicator, heated at 150°C for 30 minutes, and then aged in a thermostatic chamber at 23°C and 55% humidity for 3 days, thereby obtaining a cured polyurethane resin film.

[0122] <Impact resistance> In the evaluation of impact resistance, the above-mentioned mixed liquid was applied to a polypropylene plate to obtain a cured polyurethane resin film.

[0123] The cured film of each Example and Comparative Example was cut out with a punch blade measuring 1 cm wide x 10 cm long.

[0124] The thickness was measured near the center of the cut-out cured film using a three-point thickness gauge (Kett Electric Laboratory, dual type thickness gauge LZ990), and the average value was recorded as the thickness.

[0125] Next, a tensile test was carried out under the following measurement conditions. Each sample was measured five times, and the average values ​​of the five measurements were evaluated as the breaking strength, breaking elongation, and integral value of the stress-strain curve (shock absorption).

[0126] [Measurement conditions] Tensile tester: Intesco Model 201B Chuck spacing: 5cm Pulling speed: 100mm / min Temperature: 23℃ Humidity: 55%

[0127] The breaking strength was evaluated based on the following criteria, and the results are shown in Tables 1 to 3. [standard] ⊚: The breaking strength was 20 MPa or more. ◯: The breaking strength was 10 MPa or more and less than 20 MPa. △: The breaking strength was 5 MPa or more and less than 10 MPa. ×: The breaking strength was less than 5 MPa.

[0128] The elongation at break was evaluated according to the following criteria. The results are shown in Tables 1 to 3. [standard] ⊚: The breaking elongation was 180% or more. ◯: The breaking elongation was 150% or more and less than 180%. Δ: The breaking elongation was 100% or more and less than 150%. ×: The breaking elongation was less than 100%.

[0129] The integral value of the stress-strain curve was calculated by trapezoidal approximation using the Y-axis stress value (MPa) for each 4% interval of the X-axis strain (%). The integral value of the stress-strain curve (shock absorption) was evaluated based on the following criteria. The results are shown in Tables 1 to 3. [standard] ⊚: The integral value of the stress-strain curve was 1000 or more. ◯: The integral value of the stress-strain curve was 500 or more and less than 1,000. △: The integral value of the stress-strain curve was 300 or more and less than 500. ×: The integral value of the stress-strain curve was less than 300.

[0130] <Adhesion> For the evaluation of adhesion, the above mixed liquid was applied to a glass plate (JIS R 3202, thickness 2 mm) to obtain a cured film of polyurethane resin.

[0131] The cured films of each Example and Comparative Example were boiled for 15 minutes as a pretreatment. Then, a cross-cut test (JIS K 5600-5-6) was carried out to evaluate the adhesion. The adhesion was evaluated based on the following criteria. The results are shown in Tables 1 to 3. [standard] ⊚: The number of remaining masses was 100% before pretreatment, and the number of remaining masses was 50% or more and 100% or less after pretreatment. ◯: The number of remaining masses was 100% before pretreatment, and less than 50% after pretreatment. △: The number of remaining squares was 50% or more and 100% or less before pretreatment, and the number of remaining squares was 0% after pretreatment. ×: The number of remaining masses was less than 50% before pretreatment, and the number of remaining masses was 0% after pretreatment.

[0132] <Chemical resistance> In the evaluation of chemical resistance, the above-mentioned mixed liquid was applied to a steel plate (SPCC steel plate, PBN-144 treated product) to obtain a cured polyurethane resin film.

[0133] The cured film of each Example and Comparative Example was set in a rubbing tester (IMC-0717 type, manufactured by Imoto Manufacturing Co., Ltd.), and rubbing was performed by attaching absorbent cotton moistened with ethanol to the tip of a 0.5 kg weight. The number of reciprocating rubbing strokes when the cured film broke and the steel plate was exposed was measured.

[0134] The chemical resistance was evaluated based on the following criteria, and the results are shown in Tables 1 to 3. [standard] ⊚: The number of reciprocating rubbing cycles was 50 or more. ◯: The number of reciprocating rubbing operations was 30 or more and less than 50. △: The number of reciprocating rubbing operations was 20 or more and less than 30. ×: The number of reciprocating rubbing operations was less than 20.

[0135] [Table 1]

[0136] [Table 2]

[0137] [Table 3]

Claims

1. A polyisocyanate component containing an aliphatic diisocyanate and xylylene diisocyanate or a modified product thereof; and a polyol component including polycaprolactone polyol, A polyisocyanate composition having an isocyanate group at a molecular end, A polyisocyanate composition, wherein a ratio of the number of moles of the aliphatic diisocyanate to the number of moles of the xylylene diisocyanate or its modified product (number of moles of aliphatic diisocyanate / number of moles of the xylylene diisocyanate or its modified product) is 2.0 or more and 12.0 or less.

2. The polyisocyanate composition according to claim 1 , wherein the polycaprolactone polyol has a number average molecular weight of 250 or more and less than 2,000.

3. The raw material components further include an isocyanate silane, The polyisocyanate composition according to claim 1 or 2, wherein the mixing ratio of the isocyanate silane is 0.5 parts by mass or more and 10 parts by mass or less per 100 parts by mass of the polyisocyanate component.

4. In the polyisocyanate composition according to any one of claims 1 to 3, A blocked isocyanate composition in which an isocyanate group is blocked with a blocking agent.

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