Compositions containing zinc phenylphosphorate salts and zinc phosphorate complexes, process for the production thereof, their use as crystalline nucleating agents and

Abstract

A method for producing a composition containing a phenylphosphonic acid zinc salt and a zinc phosphate ester complex, the method including a step of simultaneously reacting a phenylphosphonic acid represented by formula (1) and a phosphate ester represented by formula (2), in formula (2), R1 represents an alkyl group, R2 represents an alkylene group, and n represents an integer of 1 or more, and when n is an integer of 2 or more, R1 represents an alkyl group, R2 represents an alkylene group, and n represents an integer of 1 or more. The plurality of R2 may be the same as or different from each other, and at least one of R2 represents an ethylene group. # imgabs0 # imgabs1 #

Description

Technical Field

[0001] The present disclosure relates to a composition containing zinc phenylphosphonate and a zinc phosphate complex, a method for producing the same, use thereof as a crystallization nucleating agent, and a moisture-curable hot-melt polyurethane resin adhesive. Background Art

[0002] Moisture-curable hot-melt polyurethane resins have excellent adhesiveness and can adjust the bonding time relatively freely, so they are suitable for adhesives used in bonding processes that require continuous production and molding processes such as sealing work, and are used in a wide range of fields. However, in applications such as wood packaging for decorative boards that require initial strength, and in applications such as electrical / electronic parts and automotive parts that require continuous production on high-speed production lines, there may be a problem that the parts enter the next process without sufficient cooling and curing of the polyurethane resin.

[0003] In order to solve the above problems, metal salts of phenylphosphonic acid compounds have been added to polyurethane resins as crystal nucleating agents to shorten the curing time. For example, Japanese Unexamined Patent Application Publication No. 2012-177016 discloses a moisture-curable hot-melt polyurethane resin adhesive containing an isocyanate-terminated polyurethane prepolymer obtained by reacting a polyol and a polyisocyanate with each other in the presence of a metal salt of an aromatic phosphonic acid as a crystal nucleating agent. SUMMARY OF THE INVENTION

[0005] According to the research of the inventors of the present invention, when a metal salt of an aromatic phosphonic acid is used as a crystal nucleating agent, there is room for further shortening the curing time of a moisture-curable hot-melt polyurethane resin.

[0006] In view of these circumstances, an object of one aspect of the present invention is to provide a composition and a method for producing the same, which can be suitably used as a nucleating agent that can further shorten the curing time of a moisture-curable hot-melt polyurethane resin. Another object of the present invention is to provide a moisture-curable hot-melt polyurethane resin adhesive having a further shortened curing time.

[0007] The inventors of the present invention have found that by using a specific phenylphosphonic acid and a specific phosphate as raw materials and reacting them simultaneously with a zinc compound, a composition containing a specific phenylphosphonic acid zinc salt and a specific zinc phosphate complex can be obtained, and the composition can be suitably used as a crystallization nucleating agent that can further shorten the curing time of a moisture-curable hot-melt polyurethane resin.

[0008] The present invention includes the following aspects.

[0009] [1] A method for producing a composition containing a zinc phenylphosphonic acid salt and a zinc phosphate complex, the method comprising the step of simultaneously reacting a phenylphosphonic acid represented by the formula (1) and a phosphate represented by the formula (2) with a zinc compound:

[0010]

[0011]

[0012] In formula (2), R 1 represents an alkyl group, R 2 represents an alkylene group, and n represents an integer greater than 1. When n is an integer greater than 2, a plurality of R 2 can be the same as or different from each other, and R 2 At least one of represents an ethylene group.

[0013] [2] The method for producing a composition according to [1], wherein the molar ratio of the amount of the phosphoric acid ester represented by formula (2) to the amount of the phenylphosphonic acid represented by formula (1) is 1 / 99 to 60 / 40.

[0014] [3] A composition comprising a phenylphosphonic acid zinc salt represented by formula (3) and a zinc phosphate complex represented by formula (4):

[0015]

[0016]

[0017] In formula (4), R 1 represents an alkyl group, R 2 represents an alkylene group, and n represents an integer greater than 1. When n is an integer greater than 2, a plurality of R2 groups may be the same as or different from each other, and R 2 At least one of represents an ethylene group.

[0018] [4] The composition according to [3], wherein the molar ratio of the amount of the zinc phosphate complex represented by formula (4) to the amount of the zinc phenylphosphonic acid salt represented by formula (3) is 1 / 99 to 60 / 40.

[0019] [5] Use of the composition according to [3] or [4] as a crystal nucleating agent.

[0020] [6] A moisture-curable hot-melt polyurethane resin adhesive comprising an isocyanate-terminated polyurethane prepolymer, a phenylphosphonic acid zinc salt represented by formula (3) and a zinc phosphate complex represented by formula (4):

[0021]

[0022]

[0023] In formula (4), R1 represents an alkyl group, R2 represents an alkylene group, and n represents an integer greater than 1. When n is an integer greater than 2, a plurality of R2 groups may be the same as or different from each other, and R 2 At least one of represents an ethylene group.

[0024] [7] The moisture-curable hot-melt polyurethane resin adhesive according to [6], wherein the molar ratio of the amount of the phosphoric acid ester represented by formula (4) to the amount of the phenylphosphonic acid represented by formula (3) is 1 / 99 to 60 / 40.

[0025] [8] The moisture-curable hot-melt urethane resin adhesive according to [6] or [7], wherein the total amount of the phenylphosphonic acid zinc salt represented by formula (3) and the zinc phosphate complex represented by formula (4) is 0.1 to 10% by mass based on the total amount of the moisture-curable hot-melt urethane resin adhesive.

[0026] One aspect of the present invention can provide a composition and a method for producing the same, wherein the composition can be suitably used as a crystallization nucleating agent that can further shorten the curing time of a moisture-curable hot-melt polyurethane resin. Another aspect of the present invention can provide a moisture-curable hot-melt polyurethane resin adhesive having a further shortened curing time.

[0027] Description of the implementation plan

[0028] The embodiments of the present invention are described in detail below. One embodiment of the present invention is a method for producing a composition containing a zinc phenylphosphonic acid salt and a zinc phosphate complex, the method comprising the step of simultaneously reacting a phenylphosphonic acid represented by formula (1) and a phosphate represented by formula (2) with a zinc compound (reaction step):

[0029]

[0030] .

[0031] In formula (2), R1 represents an alkyl group, R2 represents an alkylene group, and n represents an integer of 1 or more.

[0032] By R 1 The alkyl group represented by R may be straight chain or branched chain. 1 The number of carbon atoms in the alkyl group represented by may be 1 or more and 15 or less, 14 or less, 13 or less, or 12 or less. The phosphoric acid ester represented by formula (2) may be one in which R 1 A mixture of two or more different phosphoric acid esters.

[0033] By R 2 The alkylene group represented by R may be straight chain or branched. 2 The number of carbon atoms in the alkylene group represented by may be 1 or more or 2 or more, and 8 or less, 7 or less, 6 or less, 5 or less, 4 or less, or 3 or less. When n is an integer greater than 2, multiple R 2 May be the same as or different from each other.

[0034] R 2 At least one of the R represents an ethylene group. That is, the phosphate ester represented by formula (2) has at least one oxyethylene group. All R 2 It can be ethylene or R 2 A part of may be ethylene and the rest may be alkylene groups other than ethylene.

[0035] The letter n may be an integer of 2 or more, 3 or more, or 4 or more, and an integer of 10 or less, 9 or less, 8 or less, 7 or less, 6 or less, 5 or less, or 4 or less. The phosphoric acid ester represented by formula (2) may be a mixture of two or more phosphoric acid esters in which n is different from each other.

[0036] The average molecular weight of the phosphoric acid ester represented by formula (2) may be 100 or more, 200 or more, or 300 or more, and 900 or less, 800 or less, or 700 or less.

[0037] The average molecular weight in the present specification refers to a number average molecular weight measured by gel permeation chromatography (GPC) under the following conditions.

[0038] Measuring instrument: High-speed GPC apparatus ("HLC-8220GPC" manufactured by Tosoh Corporation)

[0039] Columns: The following columns manufactured by Tosoh Corporation were used in series connection.

[0040] “TSKgel G5000” (7.8 mm ID × 30 cm) × 1

[0041] “TSKgel G4000” (7.8 mm ID × 30 cm) × 1

[0042] “TSKgel G3000” (7.8 mm ID × 30 cm) × 1

[0043] “TSKgel G2000” (7.8 mm ID × 30 cm) × 1

[0044] Detector: RI (Differential Refractometer)

[0045] Column temperature: 40°C

[0046] Eluent: Tetrahydrofuran (THF)

[0047] Flow rate: 1.0 mL / min

[0048] Injection volume: 100 μL (sample concentration is 0.4 mass% tetrahydrofuran solution)

[0049] Standard samples: Use the following polystyrene standards to create a calibration curve.

[0050] (Standard Polystyrene)

[0051] "TSKgel Standard Polystyrene A-500" manufactured by Tosoh Corporation

[0052] "TSKgel Standard Polystyrene A-1000" manufactured by Tosoh Corporation

[0053] "TSKgel Standard Polystyrene A-2500" manufactured by Tosoh Corporation

[0054] "TSKgel Standard Polystyrene A-5000" manufactured by Tosoh Corporation

[0055] "TSKgel Standard Polystyrene F-1" manufactured by Tosoh Corporation

[0056] "TSKgel Standard Polystyrene F-2" manufactured by Tosoh Corporation

[0057] "TSKgel Standard Polystyrene F-4" manufactured by Tosoh Corporation

[0058] "TSKgel Standard Polystyrene F-10" manufactured by Tosoh Corporation

[0059] "TSKgel Standard Polystyrene F-20" manufactured by Tosoh Corporation

[0060] "TSKgel Standard Polystyrene F-40" manufactured by Tosoh Corporation

[0061] "TSKgel Standard Polystyrene F-80" manufactured by Tosoh Corporation

[0062] "TSKgel Standard Polystyrene F-128" manufactured by Tosoh Corporation

[0063] "TSKgel Standard Polystyrene F-288" manufactured by Tosoh Corporation

[0064] "TSKgel Standard Polystyrene F-550" manufactured by Tosoh Corporation

[0065] The molar ratio of the amount of the phosphoric acid ester represented by formula (2) to the amount of the phenylphosphonic acid represented by formula (1) (the amount of the phosphoric acid ester represented by formula (2) / the amount of the phenylphosphonic acid represented by formula (1)) can be 1 / 99 or more, 60 / 40 or less, or 1 / 99 to 60 / 40. The lower limit of the molar ratio can be 2 / 98, 5 / 95, 10 / 90, 15 / 85 or 20 / 80. The upper limit of the molar ratio can be 55 / 45, 50 / 50, 45 / 55, 40 / 60, 35 / 65, 30 / 70 or 25 / 75.

[0066] The zinc compound to be reacted simultaneously with the phenylphosphonic acid represented by formula (1) and the phosphoric acid ester represented by formula (2) may be, for example, zinc halide, zinc oxide or zinc acetate. The zinc halide may be zinc fluoride, zinc chloride, zinc bromide or zinc iodide.

[0067] The amount of the zinc compound may be 0.8 mol or more, 0.9 mol or more, or 0.95 mol or more, and 1.2 mol or less, 1.1 mol or less, or 1.05 mol or less, relative to 1 mol of the total amount of the phenylphosphonic acid represented by formula (1) and the phosphoric acid ester represented by formula (2).

[0068] In the reaction step, for example, the phenylphosphonic acid represented by the formula (1) and the phosphate ester represented by the formula (2) are reacted with the zinc compound simultaneously by adding an aqueous solution in which the zinc compound is dissolved in water to an aqueous solution in which the phenylphosphonic acid represented by the formula (1) and the phosphate ester represented by the formula (2) are dissolved in water. In this process, for example, the above reaction can be carried out by gradually adding an alkaline aqueous solution (e.g., an aqueous sodium hydroxide solution).

[0069] A white precipitate precipitated by the reaction was filtered out, washed with water, and then dried to obtain a composition containing phenylphosphonic acid zinc salt and zinc phosphate complex as a white powder.

[0070] The composition obtained by the above production method contains the phenylphosphonic acid zinc salt represented by formula (3) and the zinc phosphate ester complex represented by formula (4). That is, another embodiment of the present invention is a composition containing the phenylphosphonic acid zinc salt represented by formula (3) and the zinc phosphate ester complex represented by formula (4):

[0071]

[0072] .

[0073] In formula (4), R1 represents an alkyl group, R2 represents an alkylene group, and n represents an integer greater than 1. When n is an integer greater than 2, a plurality of R2 groups may be the same as or different from each other, and R 2 At least one of R represents an ethylene group. 1 , R 2 The details of R and n are the same as those of the phosphate ester represented by formula (2). 1 , R 2 Same details as n.

[0074] The average molecular weight of the zinc phosphate complex represented by formula (4) may be 150 or more, 250 or more, or 350 or more, and 950 or less, 850 or less, or 750 or less.

[0075] In the composition, the molar ratio of the amount of the zinc phosphate complex represented by formula (4) to the amount of the phenylphosphonic acid zinc salt represented by (3) (the amount of the zinc phosphate complex represented by formula (4) / the amount of the phenylphosphonic acid zinc salt represented by formula (3)) may be 1 / 99 or more, 60 / 40 or less, or 1 / 99 to 60 / 40. The lower limit of the molar ratio may be 2 / 98, 5 / 95, 10 / 90, 15 / 85 or 20 / 80. The upper limit of the molar ratio may be 55 / 45, 50 / 50, 45 / 55, 40 / 60, 35 / 65, 30 / 70 or 25 / 75.

[0076] The composition of this embodiment contains the zinc phosphate complex represented by formula (4) in addition to the zinc salt of phenylphosphonic acid represented by formula (3), and thus can further shorten the curing time of the moisture-curable hot-melt polyurethane resin compared to, for example, a composition to which only the zinc salt of phenylphosphonic acid represented by formula (3) is added. In one embodiment, the composition can improve the initial adhesive strength of the moisture-curable hot-melt polyurethane resin adhesive.

[0077] Therefore, the composition of the present embodiment can be suitably used as a crystallization nucleating agent, more specifically, as a crystallization nucleating agent that promotes the crystallization of a polyurethane resin. That is, another embodiment of the present invention is the use (application) of a composition containing a phenylphosphonic acid zinc salt represented by the above formula (3) and a zinc phosphate complex represented by the above formula (4) as a crystallization nucleating agent (a crystallization nucleating agent that promotes the crystallization of a polyurethane resin).

[0078] Another embodiment of the present invention is a moisture-curable hot-melt polyurethane resin adhesive containing an isocyanate-terminated polyurethane prepolymer, a phenylphosphonic acid zinc salt represented by the above formula (3), and a zinc phosphate complex represented by the above formula (4).

[0079] The isocyanate-terminated polyurethane prepolymer can be obtained by reacting a polyol (A) and a polyisocyanate (B) with each other in the presence of a phenylphosphonic acid zinc salt represented by the above formula (3) and a zinc phosphate complex represented by the above formula (4).

[0080] The polyol (A) may contain an aliphatic polyester polyol, two aliphatic polyester polyols (the aliphatic polyester polyol (a1) and the aromatic polyester polyol (a2) described below), or two aliphatic polyester polyols (the aliphatic polyester polyol (a1) and the aromatic polyester polyol (a2) described below) and another polyol (a3) ​​other than the aliphatic polyester polyol.

[0081] The aliphatic polyester polyol (a1) is a polyester polyol produced by a known conventional method using an aliphatic polycarboxylic acid and an aliphatic polyol as main components, and the production method thereof is not limited to a specific method.

[0082] Preferred examples of the aliphatic polycarboxylic acid used for synthesizing the aliphatic polyester polyol (a1) include 4-12 Aliphatic polycarboxylic acids such as succinic acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, decanedioic acid, dodecanedioic acid, eicosanedioic acid, citric acid, itaconic acid, citraconic anhydride and itaconic anhydride.

[0083] For example, as for the aliphatic polycarboxylic acid, lower alkyl ester derivatives such as methyl ester, acid anhydride and corresponding acid derivatives such as acid halide can be used.

[0084] The aliphatic polyol used for synthesizing the aliphatic polyester polyol (a1) is an aliphatic polyol having at least two hydroxyl groups in the molecule, preferably C 2-12 The aliphatic polyol (a1) may be linear, branched or cyclic in structure.

[0085] Examples of the aliphatic polyols include straight-chain aliphatic polyols such as ethylene glycol, 1,3-propylene glycol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,12-dodecanediol, diethylene glycol, triethylene glycol, triethylene glycol and tetraethylene glycol; branched-chain aliphatic polyols such as neopentyl glycol, 1,3-butanediol, 2,2-diethyl-1,3-propanediol, 2,2-diethylpropylene glycol, 3-methyl-1,5-pentanediol, 2-ethyl-2-butyl-1,3-propanediol, 2-methyl-1,8-octanediol, 2,4-diethyl-1, 5-pentanediol, trimethylolethane, trimethylolpropane and pentaerythritol; and alicyclic polyols such as cyclopentanediol, cyclohexanediol, cyclohexanedimethanol. Among them, ethylene glycol, 1,6-hexanediol and neopentyl glycol are preferred.

[0086] Adducts of various alkylene oxides added to hydrogenated bisphenol A, hydrogenated bisphenol F, etc. can also be used. Polymerization products obtained by ring-opening polymerization of γ-butyrolactone, ε-caprolactone, etc. using low molecular weight polyols as initiators can also be used. These can be used alone or in combination of two or more.

[0087] In the combination of aliphatic polycarboxylic acid and aliphatic polyol, the polyol (A) contains C 4-12 Aliphatic polycarboxylic acid and C 2-12 The aliphatic polyester polyol (a1) produced by the combination of aliphatic polyols further improves the viscosity stability of the hot melt polyurethane resin adhesive during the molding process and can produce an excellent effect of preventing the melt viscosity from decreasing, which is preferred.

[0088] The aromatic polyester polyol (a2) is a polyester polyol produced by a known conventional method using aromatic polycarboxylic acid and aliphatic polyol or aliphatic polycarboxylic acid and aromatic polyol as main components, and the production method is not limited to a specific method.

[0089] Aromatic polycarboxylic acids are carboxylic acids in which at least two carboxyl groups are bonded to aromatic rings, and are preferably C 8-24 Aromatic polycarboxylic acids. Examples thereof include phthalic acid, isophthalic acid, terephthalic acid, trimellitic acid, pyromellitic acid, biphenyl dicarboxylic acid, and naphthalene dicarboxylic acid. These may be used alone or in combination of two or more.

[0090] For example, for the aromatic polycarboxylic acid, lower alkyl ester derivatives such as methyl ester, acid anhydride and corresponding acid derivatives such as acid halide can be used.

[0091] Examples of the aliphatic polyol include the same aliphatic polyols as those which can be used for synthesizing the aliphatic polyester polyol (a1).

[0092] The aliphatic polyols that can be used to synthesize the aromatic polyester polyol (a2) and the aliphatic polyester polyol (a1) can be diethylene glycol, triethylene glycol, tetraethylene glycol, 1,4-bis(β-hydroxyethoxy)benzene, etc., wherein part of the carbon atoms thereof are substituted by oxygen atoms or aromatic rings. These aliphatic polyols can also be used alone or in combination of two or more.

[0093] Furthermore, it is also possible to use mixtures of polyester polyols derived from aromatic polycarboxylic acids and aliphatic polyols.

[0094] Examples of aliphatic polycarboxylic acids that can be used to synthesize the aromatic polyester polyol (a2) include C 4-12 Aliphatic polycarboxylic acid, which is the same as that exemplified as the aliphatic polycarboxylic acid which can be used for synthesizing the aliphatic polyester polyol (a1).

[0095] The aromatic polyol is not limited to a specific aromatic polyol. Examples thereof include aromatic polyols obtained from aliphatic polyols such as ethylene glycol and neopentyl glycol and aromatic polycarboxylic acids such as phthalic acid and terephthalic acid.

[0096] As the aromatic polyol, for example, adducts obtained by adding alkylene oxides such as ethylene oxide, propylene oxide and butylene oxide to bisphenol A, bisphenol F or the like can also be used.

[0097] In the synthesis process of the aliphatic polyester polyol (a1) and the aromatic polyester polyol (a2), the equivalent ratio of the hydroxyl groups possessed by the aliphatic polyol and the aromatic polyol to the carboxyl groups of the aliphatic polycarboxylic acid and the aromatic polycarboxylic acid (i.e., [OH / COOH equivalent ratio]) is preferably in the range of 1.03 to 1.50, more preferably in the range of 1.05 to 1.30. When the [OH / COOH equivalent ratio] is in such a range, a larger amount of hydroxyl-terminated polyol can be produced, and the urethanization reaction with the polyisocyanate (B) can be more easily performed, which is preferred.

[0098] The polycondensation conditions in the synthesis process of the aliphatic polyester polyol (a1) and the aromatic polyester polyol (a2) are not limited to specific conditions as long as no abnormal reaction occurs and a normal product can be obtained. Generally, a certain amount of aliphatic polycarboxylic acid and aliphatic polyol or aromatic polycarboxylic acid and aliphatic polyol can be subjected to esterification reaction or transesterification reaction for 5 to 50 hours at an internal temperature of 150 to 250° C. in the presence or absence of a catalyst, and then subjected to polycondensation reaction.

[0099] The polycondensation reaction is preferably carried out in the presence of a catalyst because the reaction proceeds easily. The catalyst is not limited to a specific catalyst. Examples thereof include titanium-based catalysts such as tetrabutoxytitanium and tin-based catalysts such as dibutyltin oxide.

[0100] The catalyst may be added together with the aliphatic polyol and the aliphatic polycarboxylic acid or the aliphatic polyol and the aromatic polycarboxylic acid, or after prepolymerization in the absence of a catalyst.

[0101] In the production of aliphatic polyester polyol (a1) and aromatic polyester polyol (a2), it is desirable to make almost all the ends hydroxyl groups, leaving as few carboxyl groups as possible, and for this purpose, adding the catalyst after conducting prepolymerization is effective and preferred.

[0102] The number average molecular weight (Mn) of the aliphatic polyester polyol (a1) and the aromatic polyester polyol (a2) is preferably in the range of 500 to 6,000, more preferably in the range of 1,000 to 5,000, particularly preferably in the range of 2,000 to 4,000. When the Mn of (a1) and (a2) is in such a range, a balance of properties such as strength and elongation according to the application can be obtained, which is preferred.

[0103] Examples of other polyols (a3) ​​include polycarbonate polyols, polylactone polyols and polyether polyols. Examples of polycarbonate polyols include polycarbonate polyols obtained using straight-chain aliphatic polyols such as 1,4-butanediol, 1,5-pentanediol and 1,6-hexanediol. Examples of polylactone polyols include polycaprolactone polyols obtained by ring-opening polymerization of caprolactone monomers. Examples of polyether polyols include polyethylene glycol, polypropylene glycol and polybutylene glycol.

[0104] In 100 parts by mass of the polyol (A), the content ratio of aliphatic polyester polyol (a1) / aromatic polyester polyol (a2) / other polyol (a3) ​​may be 20 to 60 parts by mass / 10 to 50 parts by mass / 0 to 50 parts by mass, preferably 30 to 50 parts by mass / 20 to 40 parts by mass / 10 to 20 parts by mass. When the content ratio is within such a range, the melt viscosity of the polyol (A) can be adjusted to an appropriate range, and a moisture-curable hot-melt polyurethane resin adhesive exhibiting excellent processability and miscibility and further excellent curing properties can be obtained.

[0105] Examples of the polyisocyanate (B) include well-known and commonly used aliphatic, aromatic and alicyclic polyisocyanates. Examples thereof include: aromatic diisocyanates such as diphenylmethane diisocyanate (MDI; 4,4' type, 2,4' type, 2,2' type, mixtures thereof, and crude MDI), carbodiimide-modified MDI (modified MDI), polymethylene polyphenyl polyisocyanate, carbodiimidized diphenylmethane polyisocyanate, xylene diisocyanate, toluene diisocyanate (TDI; 2,4 type, 2,6 type and mixtures thereof), xylene diisocyanate (XDI), 1,5 - naphthalene diisocyanate (NDI), tetramethylxylene diisocyanate and phenylene diisocyanate; aliphatic diisocyanates such as hexamethylene diisocyanate (HDI), dimer acid diisocyanate, norbornene diisocyanate, lysine diisocyanate and tetramethylxylene diisocyanate; and alicyclic diisocyanates such as isophorone diisocyanate (IPDI), hydrogenated diphenylmethane diisocyanate (hydrogenated MDI), hydrogenated xylene diisocyanate (hydrogenated XDI), cyclohexane diisocyanate, dicyclohexylmethane diisocyanate and isophorone diisocyanate. Among them, MDI and XDI are preferred because they react quickly with polyol (A) and moisture (water) and have excellent processability. They can be used alone or in combination of two or more.

[0106] The ratio between the polyol (A) and the polyisocyanate (B) used in synthesizing the isocyanate-terminated polyurethane prepolymer (hereinafter referred to as "prepolymer") can be within a range that does not adversely affect the reaction behavior, product quality, etc. In general, the equivalent ratio of the isocyanate group possessed by the polyisocyanate (B) to the hydroxyl group possessed by the polyol (A) (hereinafter referred to as [NCO / OH equivalent ratio]) is preferably within a range of 1.2 to 4.0, and more preferably within a range of 1.5 to 3.0. When the [NCO / OH equivalent ratio] is within such a range, the melt viscosity of the target moisture-curable hot-melt polyurethane resin composition is within an appropriate range, and properties such as excellent processability, film properties, and further excellent curing properties can be exhibited.

[0107] The reaction conditions are not limited to specific conditions as long as they are set within a range that does not adversely affect the reaction behavior, product quality, etc. Usually, they are preferably reacted at a reaction temperature of 80 to 130° C. for 1 to 10 hours.

[0108] As for the reaction method, for example, a known reaction method such as a batch reaction, a semi-continuous reaction or a continuous reaction can be selected.

[0109] The reaction can be carried out in a solvent or in the absence of a solvent. However, when the reaction is carried out in a solvent, it is preferred to remove the solvent during or after the reaction to ultimately eliminate the solvent. The method for removing the solvent is not limited to a specific method.

[0110] Based on the total amount of the moisture-curable hot-melt polyurethane resin adhesive, the total amount of the phenylphosphonic acid zinc salt represented by formula (3) and the zinc phosphate complex represented by formula (4) is 0.1% by mass or more, 10% by mass or less, or 0.1 to 10% by mass. Based on the total amount of the moisture-curable hot-melt polyurethane resin adhesive, the lower limit of the total amount may be 0.3% by mass, 0.5% by mass, or 1% by mass. Based on the total amount of the moisture-curable hot-melt polyurethane resin adhesive, the upper limit of the total amount may be 7%, 5%, or 3% by mass.

[0111] In the moisture-curable hot melt polyurethane resin adhesive, the molar ratio of the amount of the zinc phosphate complex represented by formula (4) to the amount of the phenylphosphonic acid zinc salt represented by formula (3) (the amount of the zinc phosphate complex represented by formula (4) / the amount of the phenylphosphonic acid zinc salt represented by formula (3)) can be 1 / 99 or more, 60 / 40 or less, or 1 / 99 to 60 / 40. The lower limit of the molar ratio can be 2 / 98, 5 / 95, 10 / 90, 15 / 85 or 20 / 80. The upper limit of the molar ratio can be 55 / 45, 50 / 50, 45 / 55, 40 / 60, 35 / 65, 30 / 70 or 25 / 75.

[0112] The moisture-curable hot melt polyurethane resin adhesive of the present embodiment may also contain other resins, such as previously known thermoplastic resins and thermosetting resins, and may also contain other additives. Examples of other additives include foam stabilizers, antioxidants, defoamers, UV absorbers, abrasive particles, fillers, pigments, dyes, colorants, thickeners, surfactants, flame retardants, plasticizers, lubricants, antistatic agents, heat-resistant stabilizers, adhesion-imparting agents, curing catalysts, stabilizers, fluorescent whitening agents, silane coupling agents, and waxes.

[0113] The present invention is further described in detail below based on examples. The present invention is not limited to the examples.

[0114] [Example 1]

[0115] (Production of a composition containing zinc phenylphosphonate and zinc phosphate complex)

[0116] Into a 3-liter four-necked flask, 12.3 parts by mass (78.0 mmol) of phenylphosphonic acid represented by formula (1) and 2.0 parts by mass (4.1 mmol) of a phosphoric acid ester represented by formula (2A) (wherein n represents an integer of 1 or more) having an average molecular weight of 480 and 600 parts by mass of water were added to prepare an aqueous solution.

[0117]

[0118] To the flask, an aqueous solution prepared from 11.2 parts by mass (82.2 mmol) of zinc chloride and 260 parts by mass of water was further added and mixed. Under stirring, 1,608 parts by mass of a 0.1M sodium hydroxide aqueous solution was added to the solution over 6 hours to react. The precipitated white precipitate was filtered out, washed with water, and then dried under reduced pressure at 80°C for more than 2 hours to obtain a composition 1 as a white powder, which contains a phenylphosphonic acid zinc salt represented by formula (3) and a zinc phosphate complex having an average molecular weight of 543 represented by formula (4A) (where n represents an integer greater than 1).

[0119]

[0120] (Production of moisture-curable hot-melt polyurethane resin adhesives)

[0121] In a 1-liter four-necked flask, 30 parts by mass of polypropylene glycol (Mn = 1,000), 40 parts by mass of an aliphatic polyester polyol (Mn = 4,500) obtained by reacting 1,6-hexanediol (HD) and adipic acid (AA) with each other at a mass ratio of HD / AA = 46 / 54, and 30 parts by mass of an aromatic polyester polyol (Mn = 5,000) obtained by reacting 1,6-hexanediol (HD), neopentyl glycol (NPG), ethylene glycol (EG), isophthalic acid (iPA) and terephthalic acid (tPA) with each other at a mass ratio of HD / NPG / EG / iPA / tPA = 7 / 14 / 18 / 40 / 21 were mixed together and melted to prepare polyol (A).

[0122] Next, 1.2 parts by mass (1.0% by mass based on the total amount of the binder) of Composition 1 as a crystal nucleating agent was added to (A), and the mixture was heated to 110° C. and dehydrated under reduced pressure until the moisture content reached 0.05% by mass.

[0123] Subsequently, it was cooled to 70° C., 19 parts by mass of 4,4-diphenylmethane diisocyanate was added thereto, and then the mixture was reacted at 90° C. for 3 hours until the NCO content (%) became constant to obtain a moisture-curable hot-melt polyurethane resin adhesive.

[0124] [Example 2]

[0125] The same operation as in Example 1 was performed except that 11.7 parts by mass (73.9 mmol) of phenylphosphonic acid and 3.9 parts by mass (8.2 mmol) of the phosphoric acid ester represented by formula (2A) were used to obtain Composition 2 as a white powder. The same operation as in Example 1 was performed except that Composition 2 was used to obtain a moisture-curable hot-melt polyurethane resin adhesive.

[0126] [Example 3]

[0127] The same operation as in Example 1 was performed except that 10.0 parts by mass (63.3 mmol) of phenylphosphonic acid and 9.0 parts by mass (18.8 mmol) of the phosphoric acid ester represented by formula (2A) were used to obtain Composition 3 as a white powder. The same operation as in Example 1 was performed except that Composition 3 was used to obtain a moisture-curable hot-melt polyurethane resin adhesive.

[0128] [Example 4]

[0129] The same operation as in Example 1 was performed except that 9.1 parts by mass (57.5 mmol) of phenylphosphonic acid and 11.8 parts by mass (24.6 mmol) of the phosphoric acid ester represented by formula (2A) were used to obtain Composition 4 as a white powder. The same operation as in Example 1 was performed except that Composition 4 was used to obtain a moisture-curable hot-melt polyurethane resin adhesive.

[0130] [Example 5]

[0131] The same operation as in Example 1 was performed except that 6.5 parts by mass (41.1 mmol) of phenylphosphonic acid and 19.7 parts by mass (41.1 mmol) of the phosphoric acid ester represented by formula (2A) were used to obtain Composition 5 as a white powder. The same operation as in Example 1 was performed except that Composition 5 was used to obtain a moisture-curable hot-melt polyurethane resin adhesive.

[0132] [Example 6]

[0133] In a 3-liter 4-necked flask, 12.6 parts by mass (80.0 mmol) of phenylphosphonic acid and 1.4 parts by mass (2.1 mmol) of a compound represented by the formula (2B) (wherein R1 represents C 12 H 25 or C 14 H 29 A phosphoric acid ester having an average molecular weight of 671 (represented by an alkyl group) and 600 parts by mass of water were added to prepare an aqueous solution.

[0134]

[0135] To the flask, an aqueous solution prepared from 11.2 parts by mass (82.2 mmol) of zinc chloride and 260 parts by mass of water was further added and mixed. Under stirring, 1,606 parts by mass of a 0.1M sodium hydroxide aqueous solution was added to the solution over 6 hours to react. The precipitated white precipitate was filtered out, washed with water, and then dried under reduced pressure at 80°C for more than 2 hours to obtain a composition 6 as a white powder, which contains a zinc salt of phenylphosphonic acid represented by formula (3) and a phenylphosphonic acid represented by formula (4B) (where R1 represents C 12 H 25 or C 14 H 29 A zinc phosphate complex with an average molecular weight of 753 represented by an alkyl group).

[0136]

[0137] The same operation as in Example 1 was carried out except that Composition 6 was used to obtain a moisture-curable hot-melt polyurethane resin adhesive.

[0138] [Example 7]

[0139] The same operation as in Example 6 was performed except that 12.3 parts by mass (78.0 mmol) of phenylphosphonic acid and 2.7 parts by mass (4.1 mmol) of the phosphoric acid ester represented by formula (2B) were used to obtain Composition 7 as a white powder. The same operation as in Example 1 was performed except that Composition 7 was used to obtain a moisture-curable hot-melt polyurethane resin adhesive.

[0140] [Example 8]

[0141] The same operation as in Example 6 was performed except that 11.7 parts by mass (73.9 mmol) of phenylphosphonic acid and 5.1 parts by mass (8.2 mmol) of the phosphoric acid ester represented by formula (2B) were used to obtain Composition 8 as a white powder. The same operation as in Example 1 was performed except that Composition 8 was used to obtain a moisture-curable hot-melt polyurethane resin adhesive.

[0142] [Example 9]

[0143] The same operation as in Example 6 was performed except that 10.0 parts by mass (63.3 mmol) of phenylphosphonic acid and 12.5 parts by mass (18.7 mmol) of the phosphoric acid ester represented by formula (2B) were used to obtain Composition 9 as a white powder. The same operation as in Example 1 was performed except that Composition 9 was used to obtain a moisture-curable hot-melt polyurethane resin adhesive.

[0144] [Comparative Example 1]

[0145] The same operation as in Example 1 was carried out except that Composition 1 was not added to obtain a moisture-curable hot-melt polyurethane resin adhesive.

[0146] [Comparative Example 2]

[0147] The same operation as in Example 1 was carried out, except that phenylphosphonic acid zinc salt obtained by the following procedure was used instead of Composition 1, to obtain a moisture-curable hot-melt polyurethane resin adhesive.

[0148] In a 3-liter four-necked flask, 10.0 parts by mass (63.3 mmol) of phenylphosphonic acid and 400 parts by mass of water were added to prepare an aqueous solution. To the flask, an aqueous solution prepared from 8.6 parts by mass (63.3 mmol) of zinc chloride and 200 parts by mass of water was added and mixed. Under stirring, 1,244 parts by mass of a 0.1M sodium hydroxide aqueous solution was added to the solution over 6 hours to react. The precipitated white precipitate was filtered out, washed with water, and then dried under reduced pressure at 80°C for more than 2 hours to obtain phenylphosphonic acid zinc salt as a white powder.

[0149] [Evaluation of curing time (open time)]

[0150] Each of the obtained moisture-curable hot-melt polyurethane resin adhesives of the embodiment and the comparative example was made into a heated molten state at 120°C and coated on a polypropylene sheet as a substrate with a thickness of 50 μm. Next, kraft paper as a surface member was placed on the adhesive layer coated as described above, and immediately placed in a constant temperature oven at 23°C. Based on the time point of being placed in the constant temperature oven, the time (in seconds) until the kraft paper no longer adheres to the adhesive layer was measured and determined as the curing time at 23°C (open time at 23°C). The results are listed in Table 1.

[0151] [Initial bond strength evaluation]

[0152] Each of the moisture-curable hot-melt polyurethane resin adhesives obtained in Examples and Comparative Examples was heated to a molten state at 120° C., and 1 ml of the adhesive was applied to a 4 cm 2 It was then bonded to another wood block substrate not coated with adhesive and placed in a constant temperature oven at 23°C for 3 minutes, and the tensile strength (mPa) was measured and determined as the initial bonding strength.

[0153] [Table 1]

[0154]

Claims

1. A method for producing a composition containing a zinc phenylphosphonic acid salt and a zinc phosphate complex, the method comprising the step of simultaneously reacting a phenylphosphonic acid represented by formula (1) and a phosphate represented by formula (2) with a zinc compound: In formula (2), R 1 represents an alkyl group, R 2 represents an alkylene group, and n represents an integer greater than 1, when n is an integer greater than 2, a plurality of R2 are optionally the same as or different from each other, and R 2 At least one of represents an ethylene group.

2. The method for producing a composition according to claim 1, wherein the molar ratio of the amount of the phosphoric acid ester represented by formula (2) to the amount of the phenylphosphonic acid represented by formula (1) is 1 / 99 to 60 / 40.

3. A composition comprising a zinc phenylphosphonate salt represented by formula (3) and a zinc phosphate complex represented by formula (4): In formula (4), R 1 represents an alkyl group, R 2 represents an alkylene group, and n represents an integer greater than 1, when n is an integer greater than 2, a plurality of R2 are optionally the same as or different from each other, and R 2 At least one of represents an ethylene group.

4. The composition according to claim 3, wherein the molar ratio of the amount of the phosphoric acid ester represented by formula (4) to the amount of the phenylphosphonic acid represented by formula (3) is 1 / 99 to 60 / 40.

5. Use of the composition according to claim 3 or 4 as a crystal nucleating agent.

6. A moisture-curable hot-melt polyurethane resin adhesive, comprising an isocyanate-terminated polyurethane prepolymer, a zinc phenylphosphonic acid salt represented by formula (3) and a zinc phosphate complex represented by formula (4): In formula (4), R 1 represents an alkyl group, R 2 represents an alkylene group, and n represents an integer greater than 1, when n is an integer greater than 2, a plurality of R2 are optionally the same as or different from each other, and R 2 At least one of represents an ethylene group.

7. The moisture-curable hot-melt polyurethane resin adhesive according to claim 6, wherein the molar ratio of the amount of the phosphoric acid ester represented by formula (4) to the amount of the phenylphosphonic acid represented by formula (3) is 1 / 99 to 60 / 40.

8. The moisture-curable hot-melt polyurethane resin adhesive according to claim 6 or 7, wherein the total amount of the phenylphosphonic acid zinc salt represented by formula (3) and the zinc phosphate complex represented by formula (4) is 0.1 to 10% by mass based on the total amount of the moisture-curable hot-melt polyurethane resin adhesive.

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