Isocyanate composition, its manufacturing method and application

Abstract

This specification discloses an isocyanate composition, its preparation method, and applications. The isocyanate composition has an effectiveness factor of 3.70 to 4.70. By designing and controlling the effectiveness factor, the isocyanate composition has excellent reactivity and can be used to produce high-performance polyurethane products. The isocyanate composition effectively improves the stability of polyurethane products, particularly imparting excellent discoloration resistance to polyurethane coating materials and maintaining excellent color stability under high-temperature and high-humidity environments. After a 2000-hour wet heat durability test, the color difference Δb of the coating layer is 1.2 or less, significantly improving the yellowing resistance and appearance of the coating layer.

Description

[Technical Field]

[0001] The present application relates to the technical field of isocyanates, including isocyanate compositions, their preparation methods and applications. [Background technology]

[0002] Polyurethane coatings have excellent properties such as low film formation temperature, strong adhesion, high abrasion resistance, high hardness, high chemical resistance, and excellent weather resistance, and are widely used in industrial protective coatings, wood furniture coatings, original automotive coatings, and automotive refinish coatings. Polyurethane coatings are usually composed of isocyanates and polyols. Compared to aromatic isocyanates, aliphatic isocyanates have relatively superior stability and are commonly used raw materials in polyurethane coatings. Aliphatic isocyanates can be divided into linear aliphatic isocyanates and cyclic aliphatic isocyanates depending on their molecular structure. Typical examples of the former include hexamethylene diisocyanate (HDI), and the latter, also known as alicyclic isocyanates, include dicyclohexylmethane diisocyanate (HMDI), isophorone diisocyanate (IPDI), and the like.

[0003] Aliphatic isocyanates such as HDI, HMDI, and IPDI have various advantages, but they also have the disadvantage that the isocyanates are dark in color due to the presence of trace impurities during the synthesis process, and side reactions occur during the subsequent modification process, resulting in products such as polyurethane paints that do not have sufficient color fastness.

[0004] Isocyanates can be produced by reacting the corresponding amine with phosgene (carbonyl chloride). To compensate for the shortcomings of isocyanates, researchers have improved product performance by controlling the raw materials used in isocyanate production. For example, CN101440046A discloses the production of light-colored isocyanates by reacting the corresponding amine with phosgene in the presence or absence of an inert medium, with the average PRI value of the amine stream fed to the phosgenation reaction being less than 60 moles per million moles (mpm), where PRI indicates a reducible impurity by polarographic analysis. In this production method, HDI is produced by controlling the polarographic value PRI of hexanediamine, and then a polymerization reaction is carried out to obtain HDI trimer with a low color number. CN103319372A discloses a method for producing light-colored or colorless dicyclohexylmethane diisocyanate, which includes step a) of purifying dicyclohexylmethane diamine as a raw material to obtain dicyclohexylmethane diamine containing 0.2 wt% or less of alcohol-based compounds, and step b) of phosgenating dicyclohexylmethane diamine containing 0.2 wt% or less of alcohol-based compounds to obtain dicyclohexylmethane diisocyanate, and the dicyclohexylmethane diisocyanate produced by this method has the characteristics of being light-colored or colorless. CN1356980A discloses a light-colored isocyanate, its preparation method, and uses. The method uses phosgene containing 50 ppm or less of molecular or bound bromine or iodine or a mixture thereof as a raw material, and reacts it with an amine to produce an isocyanate. The method achieves the production of a light-colored isocyanate by controlling the bromide and iodide contents in the phosgene, so that the isocyanate has a low iodine color value IFZ.CN109761855A discloses a method for producing isophorone diisocyanate, which includes the steps of reacting isophorone with hydrogen cyanide to obtain isophorone nitrile, reacting isophorone nitrile, ammonia gas, and hydrogen gas in the presence of a catalyst to obtain isophorone diamine, and phosgenating isophorone diamine to obtain isophorone diisocyanate, in which the content of impurities containing secondary amine groups in the isophorone diamine subjected to the phosgenation reaction is 0.5 wt% or less, and the method effectively reduces the content of hydrolyzed chlorine in the isophorone diisocyanate product and the color of the product.

[0005] In the methods for producing isocyanates disclosed in the related art, the color of the isocyanates can be improved to some extent by controlling the polarographic value of the amine, the content of alcohol-based impurities in the amine, the content of secondary amine group-based impurities in the amine, and the content of impurities in phosgene. However, light-colored isocyanates will darken in the subsequent modification and production of polyurethane products. The resulting polyurethane products will have serious weather resistance problems and will suffer from obvious yellowing after long-term use, which will affect the appearance and performance of polyurethane products, particularly polyurethane paints and coating layers.

[0006] Therefore, developing isocyanates with superior performance to improve the color fastness of polyurethane products, especially polyurethane paints and coating layers, is the focus of research in this field. Summary of the Invention [Problem to be solved by the invention]

[0007] The following is a summary of the subject matter discussed in detail herein, and is not intended to limit the scope of the claims.

[0008] The examples of the present application provide an isocyanate composition, its preparation method and application. By designing and controlling effective factors, the isocyanate composition can be used to prepare high-performance polyurethane products, and the discoloration resistance of polyurethane products, especially polyurethane coating materials and coating layers, can be significantly improved. [Means for solving the problem]

[0009] According to a first aspect, an embodiment of the present application provides an isocyanate composition, wherein the effectiveness factor of the isocyanate composition is 3.70 to 4.70; The formula for calculating the effectiveness factor is shown in Formula I:

number

[0010] The effectiveness factor E of the isocyanate composition according to the present application is 3.70 to 4.70, and may be, for example, 3.75, 3.80, 3.85, 3.90, 3.95, 4.00, 4.05, 4.10, 4.15, 4.20, 4.25, 4.30, 4.35, 4.40, 4.45, 4.50, 4.55, 4.60, or 4.65, or any specific point value between the above-mentioned point values. For reasons of space and clarity, the present application does not exhaustively list specific point values ​​included in the above range.

[0011] In this application, the isocyanate composition is defined as a "composition" because it includes a combination of an isocyanate and a chlorine-containing substance, and the chlorine-containing substance includes a combination of a chloroisocyanate and a substance corresponding to an effective factor. In this application, by designing and controlling the effective factors, the isocyanate composition contains a specific content and type of chlorine-containing substance, thereby exhibiting excellent reactivity and allowing it to be used in the production of high-performance polyurethane products. The isocyanate composition effectively improves the color fastness and stability of polyurethane products, particularly imparting excellent color fastness to polyurethane coating materials, maintaining excellent color stability under high-temperature and high-humidity conditions, and significantly improving the yellowing resistance and appearance of the coating layer. If the effective factor of the isocyanate composition is too high or too low, the color fastness of the polyurethane coating material will be reduced, and the coating layer will exhibit obvious yellowing under high-temperature and high-humidity conditions.

[0012] In the present application, in formula I for calculating the effectiveness factor, A is the mass content of chlorine in the isocyanate composition, and A is obtained by measuring by X-ray fluorescence spectroscopy (XRF).

[0013] In the present application, in formula I for calculating the effectiveness factor, B is the mass content of chloroisocyanate in the isocyanate composition, which is preferably obtained by measurement using chromatography-mass spectrometry, more preferably by measurement using gas chromatography-mass spectrometry (GCMS).

[0014] In this study, we found that the methods for characterizing the chlorine content in isocyanates disclosed in the related art cannot accurately control the performance of the isocyanates, and therefore cannot effectively control the quality of polyurethane products, especially the discoloration resistance of polyurethane coating materials. Specifically, the method for measuring total chlorine content in standard GB / T 12009.1-1989 uses the oxygen flask combustion method to convert all chlorine (including bromine) in the isocyanate into inorganic chlorine (including bromine), which is then titrated with silver nitrate to represent the total chlorine content in the isocyanate, including the bromine content in the isocyanate. The hydrolyzed chlorine measured in standard GB / T 12009.2-2016 specifically refers to the chlorine released after the isocyanate reacts with alcohol and water, which is the highly active chlorine in the isocyanate, including the highly active bromine, and can also hydrolyze some monochloroisocyanates. The chlorine (and some bromine) content measured by GB / T 12009.1-1989 or GB / T 12009.2-2016 cannot accurately represent the composition of isocyanates, making it difficult to effectively control the performance of isocyanate and polyurethane products.

[0015] In the preferred technical means of the present application, in calculating the effectiveness factor E, A is the total chlorine content (excluding bromine) measured by XRF, and B is the content of chloroisocyanate measured by chromatography-mass spectrometry, and the A and B values ​​are measured by accurate qualitative and quantitative analytical methods, so that the effectiveness factor E accurately represents the polychlorides and some of the hydrolyzed chlorine (excluding the hydrolyzed chlorine of monochloroisocyanate) in the isocyanate composition, and corresponds to a more precise and clear chlorine content. This partial chlorine content has an important effect on the activity of isocyanate and the performance of polyurethane products (polyurethane coating materials), realizing performance control of the isocyanate composition and further effectively improving the performance of the produced polyurethane products, especially the discoloration resistance of polyurethane coating materials.

[0016] Preferably, the isocyanate is a diisocyanate, and more preferably, an aliphatic diisocyanate including a chain aliphatic diisocyanate and / or a cyclic aliphatic diisocyanate (alicyclic diisocyanate).

[0017] Preferably, the isocyanate includes any one or a combination of at least two of pentamethylene diisocyanate (PDI), hexamethylene diisocyanate (HDI), dicyclohexylmethane diisocyanate (HMDI), and isophorone diisocyanate (IPDI).

[0018] In this application, unless otherwise stated, the isocyanates listed include all isomers thereof, for example, dicyclohexylmethane diisocyanate (HMDI) is [ka] is.

[0019] Preferably, the mass percentage of isocyanate in the isocyanate composition is 97% or more, for example, 97.5%, 98%, 98.5%, 99%, 99.1%, 99.2%, 99.3%, 99.4%, 99.5%, 99.6%, 99.7%, 99.8%, 99.9%, 99.92%, 99.95%, 99.98%, 99.99%, etc., and more preferably 99% or more.

[0020] Preferably, the substance corresponding to the effective factor includes any one or a combination of at least two of the following compounds: [ka] R is a divalent group formed by removing the NCO group in an isocyanate.

[0021] Preferably, R is a C6 linear or branched alkylene group (e.g., [ka] isocyanate is HDI), C5 linear or branched alkylene group (e.g., [ka] isocyanate is PDI), [ka] (wherein the isocyanate is HMDI), [ka] (wherein the isocyanate is IPDI), and the wavy line indicates the linking site of the group.

[0022] Preferably, the chloroisocyanate is a compound in which one NCO group in an isocyanate is substituted with chlorine.

[0023] Preferably, the chloroisocyanate is [ka] (Chlorohexyl isocyanate CHI, isocyanate is HDI), [ka] (chloropentyl isocyanate CPI, isocyanate is PDI), [ka] (chlorodicyclohexylmethane isocyanate CHMI, the isocyanate is HMDI), [ka] (chloroisophorone diisocyanate CIPI, isocyanate is IPDI), R 1 is a C6 linear or branched alkylene group (e.g., [ka] ) and R 2 is a C5 linear or branched alkylene group (e.g., [ka] )

[0024] Preferably, the chloroisocyanate is [ka] The present invention includes any one or a combination of at least two of the above.

[0025] In this specification, the representation of a ring structure surrounded by "-" indicates that the linking site is at any available position on the ring structure.

[0026] Preferably, the chlorine mass content (A value) in the isocyanate composition is 2 to 1000 ppm, and may be, for example, 5 ppm, 10 ppm, 50 ppm, 100 ppm, 150 ppm, 200 ppm, 250 ppm, 300 ppm, 350 ppm, 400 ppm, 450 ppm, 500 ppm, 550 ppm, 600 ppm, 650 ppm, 700 ppm, 750 ppm, 800 ppm, 850 ppm, 900 ppm, or 950 ppm, or a specific point value between the above point values. For reasons of space and clarity, the present application does not comprehensively list specific point values ​​included in the above range, and more preferably, the A value is 20 to 900 ppm.

[0027] Preferably, the mass content (B value) of chloroisocyanate in the isocyanate composition is 5 to 3000 ppm, and may be, for example, 20 ppm, 50 ppm, 100 ppm, 300 ppm, 500 ppm, 700 ppm, 900 ppm, 1000 ppm, 1100 ppm, 1300 ppm, 1500 ppm, 1700 ppm, 1900 ppm, 2000 ppm, 2100 ppm, 2300 ppm, 2500 ppm, 2700 ppm, or 2900 ppm, or a specific point value between the above point values; for the sake of space and clarity, this application does not comprehensively list specific point values ​​included in the above range.

[0028] In this application, "ppm" means parts per million, and 1 ppm means one part per million, and hereinafter, when the same expression is used, it all has the same meaning.

[0029] In the present application, the substance corresponding to the effective factor, chloroisocyanate, may be produced as a by-product in the isocyanate production process, or may be artificially added to obtain the required content.

[0030] According to a second aspect, an embodiment of the present application provides a method for producing the isocyanate composition according to the first aspect, the method comprising reacting an amine compound with phosgene to obtain the isocyanate composition.

[0031] Preferably, the manufacturing method comprises: Step (1) of reacting an amine compound with phosgene to obtain a reaction product; Step (2) of subjecting the reaction product obtained in step (1) to a removal treatment including a phosgen removal treatment and / or a solvent removal treatment to obtain a crude product; and step (3) of sequentially separating and purifying the crude product obtained in step (2) to obtain the isocyanate composition.

[0032] Preferably, in step (3), a heavy component and an intermediate are obtained by the separation, and a mixture of the intermediate and the heavy component is purified to obtain the isocyanate composition, and the mass percentage of the heavy component in the mixture is 1 to 10%.

[0033] In a preferred technical means of the present application, the component to be refined is a mixture of the intermediate and a heavy component, and the mass percentage of the heavy component in the mixture is 1 to 10%, for example, 2%, 3%, 4%, 5%, 6%, 7%, 8%, or 9%, and may be a specific point value between the above point values. For the sake of space and clarity, the present application does not exhaustively list the specific point values ​​included in the range, and more preferably, it is 2 to 10%.

[0034] Preferably, the heavy components obtained by the separation are directly mixed with the intermediate to obtain a mixture, or the heavy components obtained by the separation are primary heavy components, and the primary heavy components are separated again to obtain a heavy component recovery material and residual heavy components, and the heavy component recovery material is mixed with the intermediate to obtain the mixture, and the mass percentage of the heavy component recovery material in the mixture is 1 to 10%.

[0035] In another preferred technical means, the method for producing the isocyanate composition includes a step of mixing the isocyanate obtained by the urethane decomposition method with the heavy component recovery material to obtain the isocyanate composition. Preferably, the mass percentage of the heavy component recovery material in the isocyanate composition is 1 to 10% (e.g., 2%, 3%, 4%, 5%, 6%, 7%, 8%, or 9%), more preferably 1 to 5%.

[0036] As a preferred technical means of the present application, the method for producing the isocyanate composition is a phosgenation method, i.e., an amine compound is reacted with phosgene to produce an isocyanate, and the amine compound includes a diamine and / or a diamine salt (e.g., a diamine hydrochloride obtained by reacting a diamine with HCl).

[0037] Preferably, the method for reacting the amine compound with phosgene includes, for example, three methods: a method for reacting a diamine with phosgene in a gas phase, also called a gas-phase phosgenation method; a method for reacting a diamine with phosgene in a liquid phase, also called a liquid-phase phosgenation method; and a method for reacting a diamine salt (e.g., diamine hydrochloride) with phosgene in a solvent, also called a diamine hydrochloride phosgenation method, with the gas-phase phosgenation method being more preferred.

[0038] Preferably, the reaction described in step (1) is carried out in a reaction zone in the presence or absence of an inert medium.

[0039] Preferably, the reaction described in step (1) is carried out in the gas phase, i.e., a gas phase phosgenation process, in which the vaporization of the amine compound (diamine) is carried out in advance, and the resulting gas phase diamine is free from liquid droplets before entering the reaction zone.

[0040] Preferably, the reaction described in step (1) can be carried out in a batch, semi-continuous or continuous manner, more preferably in a continuous manner.

[0041] Preferably, the inert medium is any one or a combination of at least two selected from nitrogen gas, a rare gas (e.g., argon gas and / or helium gas), an aromatic compound (e.g., chlorobenzene, dichlorobenzene, toluene, xylene), carbon monoxide, carbon dioxide, etc., and more preferably any one or a combination of at least two selected from nitrogen gas, chlorobenzene, or dichlorobenzene.

[0042] Preferably, the amount of the inert medium used is calculated based on the gas volume of the vaporized inert medium, and the volume ratio of the inert medium (gas) to the diamine (gas) is (0.01 to 5):1, and may be, for example, 0.02:1, 0.05:1, 0.08:1, 0.1:1, 0.3:1, 0.5:1, 0.8:1, 1:1, 1.5:1, 2:1, 2.5:1, 3:1, 3.5:1, 4:1, or 4.5:1, and is more preferably (0.05 to 3):1, and even more preferably (0.1 to 1):1.

[0043] Preferably, the specific method of the reaction described in step (1) includes the step of introducing vaporized diamine and phosgene into a reaction zone to react with each other to obtain a reaction product.

[0044] Preferably, the molar ratio of the phosgene to the amine compound (diamine) is (2.5 to 20):1, and may be, for example, 3:1, 5:1, 7:1, 9:1, 10:1, 11:1, 13:1, 15:1, 17:1, or 19:1, and is preferably (4 to 10):1, and more preferably (6 to 10):1.

[0045] Preferably, the temperature of the reaction described in step (1) is 300 to 500°C, and may be, for example, 310°C, 330°C, 350°C, 370°C, 390°C, 400°C, 410°C, 430°C, 450°C, 470°C, or 490°C, or a specific point value between the above point values; for the sake of space and clarity, the present application does not exhaustively list specific point values ​​included in the above range, and the temperature is more preferably 350 to 450°C.

[0046] Preferably, the absolute pressure of the reaction described in step (1) is 0.05 to 0.3 MPa, for example, 0.06 MPa, 0.08 MPa, 0.1 MPa, 0.12 MPa, 0.15 MPa, 0.18 MPa, 0.2 MPa, 0.22 MPa, 0.25 MPa, or 0.28 MPa, and may be a specific point value between the above-mentioned point values. For the sake of space and clarity, the present application does not exhaustively list specific point values ​​included in the above range, and is more preferably 0.07 to 0.2 MPa, and even more preferably 0.09 to 0.18 MPa.

[0047] Preferably, the flow velocities of the vaporized diamine and phosgene feed streams entering the reaction zone are each independently 5 to 100 m / s, and may be, for example, 10 m / s, 15 m / s, 20 m / s, 25 m / s, 30 m / s, 35 m / s, 40 m / s, 45 m / s, 50 m / s, 55 m / s, 60 m / s, 65 m / s, 70 m / s, 75 m / s, 80 m / s, 85 m / s, 90 m / s, or 95 m / s, or specific point values ​​between the above point values. For reasons of space and clarity, the present application does not exhaustively list specific point values ​​included in the above range, and more preferably, the flow velocities are 10 to 80 m / s.

[0048] Preferably, the average contact time between the amine compound (diamine) and phosgene in the reaction zone is 0.01 to 15 seconds, and may be, for example, 0.02 seconds, 0.05 seconds, 0.08 seconds, 0.1 seconds, 0.3 seconds, 0.5 seconds, 0.8 seconds, 1 second, 2 seconds, 3 seconds, 4 seconds, 5 seconds, 6 seconds, 7 seconds, 8 seconds, 9 seconds, 10 seconds, 11 seconds, 12 seconds, 13 seconds, or 14 seconds, or a specific point value between the above-mentioned point values. For reasons of space and clarity, the present application does not comprehensively list specific point values ​​included in the above range, and the average contact time is more preferably 0.04 to 10 seconds, and even more preferably 0.08 to 5 seconds.

[0049] Preferably, the reaction product of the amine compound (diamine) and phosgene described in step (1) is spray washed (collected) in a single stage or multiple stages using an inert solvent, and the temperature of the product is reduced to 150°C or less to obtain the reaction product (reaction liquid containing isocyanate).

[0050] Preferably, the inert solvent is an organic solvent, and examples thereof include aromatic hydrocarbons such as benzene, toluene, and xylene; aliphatic hydrocarbons such as octane and decane; alicyclic hydrocarbons such as cyclohexane, methylcyclohexane, and ethylcyclohexane; halogenated aromatic hydrocarbons such as chlorotoluene, chlorobenzene, dichlorobenzene, dibromobenzene, and trichlorobenzene; nitrogen-containing compounds such as nitrobenzene, N,N-dimethylformamide, N,N-dimethylacetamide, and N,N-dimethylimidazolidinone; ethers such as dibutyl ether, ethylene glycol dimethyl ether, and ethylene glycol diethyl ether; ketones such as heptanone, diisobutyl ketone, methyl isobutyl ketone, and methyl ethyl ketone; fatty acid esters such as ethyl acetate, butyl acetate, amyl acetate, and ethoxyethyl acetate; and aromatic carboxylic acid esters such as methyl salicylate, dimethyl phthalate, dibutyl phthalate, and methyl benzoate, but are not limited thereto. The inert solvents may be used alone or in combination of at least two kinds.

[0051] Preferably, the inert solvent comprises a halogenated aromatic hydrocarbon, more preferably chlorobenzene and / or dichlorobenzene.

[0052] If necessary, the reaction product obtained in step (1) may be subjected to a removal step (solvent removal step and / or phosgene removal step) and a separation and purification step.

[0053] Preferably, the dephosgenation treatment described in step (2) is carried out in a dephosgenation tower.

[0054] Preferably, the desolvation treatment described in step (2) is carried out in a desolvation tower.

[0055] Preferably, the separation in step (3) separates the intermediate (light component) from the heavy component and removes the heavy component, and the separation device illustratively includes, but is not limited to, a short-path evaporator and a distillation column.

[0056] Preferably, the operating pressure of the short stroke evaporator is 0.05 to 4 kPa, for example, 0.08 kPa, 0.1 kPa, 0.3 kPa, 0.5 kPa, 0.8 kPa, 1 kPa, 1.2 kPa, 1.5 kPa, 1.8 kPa, 2 kPa, 2.2 kPa, 2.5 kPa, 2.8 kPa, 3 kPa, 3.2 kPa, 3.5 kPa, or 3.8 kPa, and may be a specific point value between the above point values. For the sake of space and clarity, the present application does not exhaustively list the specific point values ​​included in the range, and more preferably, it is 0.1 to 2.5 kPa.

[0057] In a preferred technical means of the present application, the heavy components obtained by the separation contain a wide variety of chlorine-containing substances with a high content. The heavy components or heavy component recovery material obtained by re-separating the heavy components are added at a certain ratio to the intermediate (light components) obtained by the separation, and the intermediate is further purified. This effectively adjusts the type and content of chlorine-containing substances in the product, and the effectiveness factor of the isocyanate composition can be set to 3.90 to 5.70.

[0058] Preferably, the mass percentage of the heavy component (heavy component recovery material) in the mixture (materials involved in purification) is 1 to 10%, more preferably 2 to 10%, resulting in an effectiveness factor of 3.70 to 4.70 for the isocyanate composition. If the amount of heavy component (heavy component recovery material) added is too small, the effectiveness factor will be high, and when the isocyanate composition is used to produce polyurethane products, the reaction rate will be too fast and the discoloration resistance will be poor. If the amount of heavy component (heavy component recovery material) added is too high, the effectiveness factor will be low and the isocyanate composition will contain many impurities, which will affect the discoloration resistance and stability of the polyurethane product, and the polyurethane coating material will exhibit obvious yellowing in a humid and hot environment.

[0059] Preferably, the heavy components mixed with the intermediate are directly reintroduced into the intermediate, or are circulated and separated through a heavy component removal device to obtain a heavy component recovery material, which can be reintroduced into the intermediate.

[0060] Preferably, the purification method is an industrial separation technique known in the art, including, but not limited to, distillation, rectification, crystallization, and the like.

[0061] Preferably, the purification method described in step (3) is rectification.

[0062] Preferably, the rectification is carried out in a rectification column, which preferably comprises a tray rectification column or a packed rectification column.

[0063] Preferably, the number of theoretical plates of the rectification column is 2 to 60, and may be, for example, 3, 5, 8, 10, 12, 15, 18, 20, 22, 25, 28, 30, 32, 35, 38, 40, 42, 45, 48, 52, 52, 55, or 58, or a specific point value between the above-mentioned point values. For the sake of space and clarity, the present application does not exhaustively list specific point values ​​included in the above range, and more preferably, the number of theoretical plates is 5 to 40.

[0064] Preferably, the pressure at the top of the rectification column is 0.1 to 4 kPa, for example, 0.2 kPa, 0.5 kPa, 0.8 kPa, 1 kPa, 1.2 kPa, 1.5 kPa, 1.8 kPa, 2 kPa, 2.2 kPa, 2.5 kPa, 2.8 kPa, 3 kPa, 3.2 kPa, 3.5 kPa, or 3.8 kPa, and may be a specific point value between the above point values. For reasons of space and clarity, the present application does not exhaustively list specific point values ​​included in the above range, and more preferably, the pressure is 0.15 to 2.5 kPa.

[0065] Preferably, the top reflux ratio of the rectification column is 0.01 to 60, and may be, for example, 0.05, 0.1, 0.5, 1, 3, 5, 8, 10, 12, 15, 18, 20, 22, 25, 28, 30, 32, 35, 38, 40, 42, 45, 48, 50, 52, 55, or 58, or a specific point value between the above point values. For the sake of space and clarity, the present application does not comprehensively list specific point values ​​included in the above range, and more preferably, it is 0.1 to 40.

[0066] In a preferred technical means of the present application, the method for producing the isocyanate composition includes the following steps: In the phosgenation step (1), vaporized diamine is reacted with phosgene, and the resulting product is spray washed (collected) with an inert solvent to obtain a reaction product. In step (2) the removal step, the reaction product obtained in step (1) is subjected to a removal treatment including a phosgene removal treatment and / or a solvent removal treatment to obtain a crude product. In step (3a) the separation step, the crude product obtained in step (2) is separated to obtain a heavy component and an intermediate (light component). In step (3b) of the heavy component recovery process, the intermediate obtained in step (3a) is mixed with the heavy component to obtain a mixture, and the mass percentage of the heavy component in the mixture is 1 to 10%; or the heavy component obtained in step (3a) is subjected to secondary separation to obtain a heavy component recovery material and residual heavy components, and the heavy component recovery material is mixed with the intermediate to obtain a mixture, and the mass percentage of the heavy component recovery material in the mixture is 1 to 10%. In step (3c) the purification step, the mixture obtained in step (3b) is purified to obtain the isocyanate composition.

[0067] 1, the production method includes a phosgenation step 10, a removal step 20, a separation step 30, a heavy component recovery step 40, and a purification step 50. The phosgenation step can be carried out batchwise or continuously. The effective factors of the isocyanate composition can be adjusted by appropriately adjusting the mixing ratio of the heavy component and the intermediate, the phosgene supply ratio, the reaction temperature, the reflux ratio of the rectification column, etc., and the effective factors can be controlled mainly by the mixing ratio of the heavy component and the intermediate.

[0068] Specifically, taking the HDI composition as an example, the production method is as follows.

[0069] (1) In the phosgenation step, a tubular reactor is used to mix vaporized 1,6-hexanediamine with a suitable nitrogen gas, and then the mixture is continuously reacted with phosgene in the tubular reactor. The resulting product is removed from the reaction zone and then continuously spray-washed (collected) with chlorobenzene to obtain a reaction product, i.e., a reaction liquid containing isocyanate.

[0070] This allows the phosgenation step to be carried out continuously.

[0071] This allows the salt production step and the phosgenation step to be carried out continuously.

[0072] (2) In the removal step, a dephosgenation tower and a desolvation tower are used, the reaction liquid is continuously supplied to the middle of the dephosgenation tower, phosgene, hydrogen chloride, etc. are removed from the reaction liquid using the dephosgenation tower, and then the solvent is removed from the reaction liquid using the desolvation tower to obtain a crude HDI product.

[0073] (3a) In the separation step, the above-mentioned HDI crude product is separated in a short-path evaporator to remove heavy components, thereby obtaining intermediates and primary heavy components.

[0074] (3b) In the heavy component recovery process, the primary heavy components are recovered using a short-stroke evaporator to obtain a heavy component recovery material and a secondary heavy component, which can be recovered in one go or in a cycle. The mixture obtained by mixing the heavy component recovery material and the intermediate is sent to a purification process, and the mass percentage of the heavy component recovery material in the mixture is 1 to 10%.

[0075] (3c) In the purification step, the mixture is continuously fed to a rectification column, and then low boiling points are distilled off from the intermediate under the rectification conditions described above (column bottom temperature, column top temperature, column top pressure, column bottom reflux ratio, column top reflux ratio, residence time), and the HDI composition is collected from slightly below the middle of the column.

[0076] This allows continuous production of HDI compositions containing substances corresponding to HDI, CHI, and effective factors.

[0077] According to a third aspect, the present invention provides a modified isocyanate composition obtained by modifying the isocyanate composition described in the first aspect.

[0078] The modified isocyanate composition contains any one or a combination of at least two of (a) an isocyanurate group, (b) a uretdione group, (c) a biuret group, (d) a urethane group, (e) a urea group, (f) an iminooxadiazinedione group, (g) an allophanate group, (h) a uretonimine group, and (i) a carbodiimide group.

[0079] Those skilled in the art can modify the above-described isocyanate composition by a known method, as needed, to obtain the modified isocyanate composition, and the modified isocyanate composition can be suitably used as an isocyanate-based substance (polyisocyanate component) and as a raw material for active hydrogen group-containing substances and polymers such as polyurethane.

[0080] Specifically, the (a) modified isocyanate composition containing an isocyanurate group is an isocyanate trimer, and can be obtained, for example, by reacting an isocyanate composition in the presence of a known isocyanuration catalyst to convert the isocyanate therein into an isocyanurate.

[0081] The (b) modified isocyanate composition containing a uretdione group can be obtained by heating the isocyanate composition at 90 to 200°C or by reacting it in the presence of a known uretdione-forming catalyst to uretdioneize (e.g., dimerize) the isocyanate.

[0082] The (c) biuret group-containing modified isocyanate composition can be obtained by reacting the isocyanate composition with, for example, water, a tertiary alcohol (e.g., tert-butyl alcohol), a secondary amine (e.g., dimethylamine, diethylamine), or the like, and then further reacting the resulting mixture in the presence of a known biuretization catalyst.

[0083] The (d) modified isocyanate composition containing a urethane group can be obtained by reacting an isocyanate composition with a polyol component (for example, trimethylolpropane).

[0084] The (e) urea group-containing modified isocyanate composition can be obtained by reacting an isocyanate composition with water, a polyamine component, and the like.

[0085] The (f) modified isocyanate composition containing an iminooxadiazinedione group is an asymmetric trimer of isocyanate, and is obtained by reacting an isocyanate composition in the presence of a known iminooxadiazinedione-forming catalyst to convert the isocyanate into an iminooxadiazinedione (e.g., trimerization).

[0086] The (g) modified isocyanate composition containing allophanate groups can be obtained by reacting an isocyanate composition with an alcohol, followed by further reaction in the presence of a known allophanate-forming catalyst.

[0087] The (h) modified isocyanate composition containing uretonimine groups can be obtained by reacting an isocyanate composition in the presence of a known carbodiimide catalyst to form carbodiimide groups, and then adding an isocyanate to the carbodiimide groups.

[0088] The (i) modified isocyanate composition containing a carbodiimide group can be obtained by reacting an isocyanate composition in the presence of a known carbodiimide catalyst.

[0089] The modified isocyanate composition may contain at least one of the above (a) to (i), or may contain at least two of them. Such a modified isocyanate composition can be produced by appropriately combining the above reactions. The modified isocyanate composition can be used alone or in combination of two or more types.

[0090] Taking an HDI composition as an example, a person skilled in the art can modify the HDI composition by a known method as needed to obtain a modified HDI composition, and the modified HDI composition can be suitably used as an isocyanate-based substance (polyisocyanate component) and as a raw material for active hydrogen group-containing substances and polyurethanes.

[0091] According to a fourth aspect, an embodiment of the present application provides an isocyanate-based polymer, the polymer being obtained by reacting an isocyanate-based substance with an active hydrogen group-containing substance, and the isocyanate-based substance includes at least one of the isocyanate composition described in the first aspect and the modified isocyanate composition described in the third aspect.

[0092] Preferably, the active hydrogen group includes any one or a combination of at least two of a hydroxyl group, an amino group, and a mercapto group.

[0093] Preferably, the active hydrogen group-containing substance includes any one or a combination of at least two of polyols, polyamines, and polythiols.

[0094] When the active hydrogen group-containing substance is a polyol, the polymer is a polyurethane; when the active hydrogen group-containing substance is a polyamine, the polymer is a polyurea; and when the active hydrogen group-containing substance is a polythiol, the polymer is a polythiourethane.

[0095] According to a fifth aspect, an embodiment of the present application provides a two-component polyurethane composition, the two-component polyurethane composition comprising a component A and a component B, the component A comprising the isocyanate composition according to the first aspect and / or the modified isocyanate composition according to the third aspect, and the component B comprising an active hydrogen group-containing substance.

[0096] The two-component polyurethane composition, which is a two-liquid type having an isocyanate-based material including the isocyanate composition and / or the modified isocyanate composition as component A and an active hydrogen group-containing material as component B, can be used as a coating material such as a paint or adhesive, a two-component curing sealing material, a potting agent, etc. The two-component polyurethane composition is a raw material in which component A (curing agent) and component B (main component) are mixed together just before use.

[0097] The coating raw material is a two-component curing resin raw material for forming a coating layer, and includes component A (curing agent) and component B (main component). The coating layer may also include paint, adhesive, etc.

[0098] When the coating raw material is used as a paint, its applications include, but are not limited to, paints for plastics, paints for automobile exteriors, paints for automobile interiors, paints for electrical / 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).

[0099] Preferably, the component A contains a modified isocyanate composition obtained by modifying the isocyanate composition, and preferably contains (a) an isocyanurate group and / or (d) a urethane group.

[0100] Furthermore, the component A may contain other aromatic isocyanates, aliphatic isocyanates, or araliphatic isocyanates, as necessary.

[0101] In the present application, component A in the two-component polyurethane composition comprises the isocyanate composition and / or the modified isocyanate composition, and the isocyanate composition has an effectiveness factor of 3.70 to 4.70, and the modified isocyanate composition is obtained by modifying the isocyanate composition having an effectiveness factor of 3.70 to 4.70. By designing and controlling the effectiveness factor, the two-component polyurethane composition can effectively inhibit discoloration of the coating layer as a two-component polyurethane paint, and the coating layer maintains excellent stability in high-temperature and high-humidity environments, significantly improving the discoloration resistance of the coating layer.

[0102] Preferably, the active hydrogen group in component B includes any one or a combination of at least two of a hydroxyl group, an amino group, and a mercapto group (thiol group).

[0103] Preferably, the component B contains one or a combination of at least two of the following: a polyol (a component containing at least two hydroxyl groups), a polythiol (a component containing at least two mercapto groups / thiol groups), and a polyamine (a component containing at least two amino groups).

[0104] Preferably, the component B includes a polyol.

[0105] Preferably, the polyol comprises a low molecular weight polyol and / or a high molecular weight polyol.

[0106] Preferably, the low-molecular-weight polyol is a compound containing at least two hydroxyl groups and having a number average molecular weight of 60 to 400 (for example, 80, 100, 150, 200, 250, 300, or 350).

[0107] Illustratively, the low molecular weight polyol may be, for example, ethylene glycol, propylene glycol, 1,3-propanediol, 1,4-butanediol, 1,3-butanediol, 1,2-butanediol, 1,5-pentanediol, 1,6-hexanediol, neopentyl glycol, C7-C22 alkanediol, diethylene glycol, triethylene glycol, dipropylene glycol, 3-methyl-1,5-pentanediol, C17-C20 alkane-1,2-diol, isosorbide, 1,3-cyclohexanedimethanol, 1,4-cyclohexanedimethanol, 1,4-cyclohexanediol, hydrogenated Examples of alcohols include diols such as bisphenol A, 1,4-dihydroxy-2-butene, 2,6-dimethyl-1-octene-3,8-diol, and bisphenol A; trihydric alcohols such as glycerin and trimethylolpropane; tetrahydric alcohols such as tetramethylolmethane (pentaerythritol) and diglycerin; pentahydric alcohols such as xylitol; hexahydric alcohols such as sorbitol, mannitol, allitol, iditol, dulcitol, altritol, inositol, and dipentaerythritol; heptahydric alcohols such as perseitol; and octahydric alcohols such as sucrose.

[0108] Also included in the low molecular weight polyols are polyalkylene oxides (random and / or block copolymers containing at least two alkylene oxides) having a number average molecular weight of 60 to 400, which are obtained by adding alkylene oxides such as ethylene oxide and propylene oxide to the above alcohols as initiators.

[0109] Preferably, the high molecular weight polyol is a compound containing at least two hydroxyl groups and having a number average molecular weight of 400 to 1000 (e.g., 500, 800, 1000, 2000, 3000, 4000, 5000, 6000, 7000, 8000, or 9000), and more preferably, the number average molecular weight of the high molecular weight polyol is 400 to 5000.

[0110] Preferably, the high molecular weight polyol includes any one or a combination of at least two of polyether polyol, polyester polyol, polycarbonate polyol, polyurethane polyol, epoxy polyol, vegetable oil polyol, polyolefin polyol, acrylic polyol, polysiloxane polyol, fluorine-containing polyol, and vinyl monomer-modified polyol.

[0111] Illustrative examples of the polyether polyol include polyoxy(C2-C3) alkylene polyol, polytetramethylene ether glycol, polytrimethylene ether glycol, etc. Examples of polyoxy(C2-C3) alkylene polyols include addition polymers of C2-C3 alkylene oxides such as ethylene oxide and propylene oxide (random and / or block copolymers containing at least two alkylene oxides) using the low-molecular-weight polyols listed above as initiators. Specific examples of polyoxy(C2-C3) alkylene groups include polyethylene glycol, polypropylene glycol, and polyethylene-polypropylene copolymers. Examples of polytetramethylene ether glycols include ring-opening polymers (polytetramethylene ether glycol) obtained by cationic polymerization of tetrahydrofuran, and amorphous polytetramethylene ether glycols obtained by copolymerizing tetrahydrofuran polymerized units with the diols listed above. Other examples include plant-derived polytetramethylene ether glycols that use tetrahydrofuran, which is produced from plant-derived materials such as furfural, as a starting material. An example of polytrimethylene ether glycol is a polyol produced by polycondensation of plant-derived 1,3-propylene glycol.

[0112] Illustratively, the polyester polyol includes a polycondensate obtained by reacting the above-mentioned low-molecular-weight polyol (preferably, diol) with a polybasic acid (preferably, dibasic acid) under known conditions.

[0113] Examples of polybasic acids include saturated aliphatic dicarboxylic acids (C11-C13) such as oxalic acid, malonic acid, succinic acid, methylsuccinic acid, glutaric acid, adipic acid, 1,1-dimethyl-1,3-dicarboxypropane, 3-methyl-3-ethylglutaric acid, azelaic acid, and sebacic acid; unsaturated aliphatic dicarboxylic acids such as maleic acid, fumaric acid, and itaconic acid; aromatic dicarboxylic acids such as phthalic acid, isophthalic acid, terephthalic acid, toluenedicarboxylic acid, and naphthalenedicarboxylic acid; and hexacarboxylic acids. Examples of suitable alicyclic dicarboxylic acids include hydrophthalic acid, other carboxylic acids such as dimer acid, hydrogenated dimer acid, and HET acid, and acid anhydrides derived from the above-mentioned carboxylic acids, such as oxalic anhydride, succinic anhydride, maleic anhydride, phthalic anhydride, 2-alkyl (C12-C18) succinic anhydride, tetrahydrophthalic anhydride, and trimellitic anhydride, as well as acid halides derived from these carboxylic acids, such as oxalic acid dichloride, adipic acid dichloride, and sebacic acid dichloride.

[0114] Further, examples of polyester polyols include vegetable oil-based polyester polyols obtained by subjecting the above-mentioned low-molecular-weight polyols and hydroxyl group-containing vegetable oil fatty acids (e.g., hydroxycarboxylic acids such as castor oil fatty acids containing ricinoleic acid and hydrogenated castor oil fatty acids containing 12-hydroxystearic acid) to a condensation reaction under known conditions.

[0115] Examples of polyester polyols include polycaprolactone polyols and polyvalerolactone polyols obtained by ring-opening polymerization of lactones such as ε-caprolactone and γ-valerolactone using the above-mentioned low-molecular-weight polyols (preferably diols) as an initiator, and lactone-based polyester polyols obtained by copolymerizing these with the above-mentioned diols.

[0116] Illustrative examples of the polycarbonate polyol include a ring-opening polymer of ethylene carbonate using the low-molecular-weight polyol (preferably, a diol) as an initiator, such as an amorphous polycarbonate polyol obtained by copolymerizing the diol and the ring-opening polymer.

[0117] Illustrative examples of the polyurethane polyol include polyester polyurethane polyol, polyether polyurethane polyol, polycarbonate polyurethane polyol, and polyester polyether polyurethane polyol, which are obtained by reacting the polyester polyol, polyether polyol, and / or polycarbonate polyol obtained as described above with the polyisocyanate (including HDI, the same applies hereinafter) in such a ratio that the equivalent ratio (OH / NCO) of the hydroxyl group to the isocyanate group is greater than 1.

[0118] Illustrative examples of the epoxy polyol include those obtained by reacting the low-molecular-weight polyols with polyfunctional halohydrins such as epichlorohydrin and β-methylepichlorohydrin.

[0119] Illustrative examples of the vegetable oil polyol include hydroxyl group-containing vegetable oils such as castor oil and coconut oil, etc. Examples include castor oil polyol and ester-modified castor oil polyol obtained by reacting castor oil polyol with polypropylene polyol.

[0120] Illustrative examples of the polyolefin polyol include polybutadiene polyol and partially saponified ethylene-vinyl acetate copolymer.

[0121] Illustrative examples of the acrylic polyol include copolymers obtained by copolymerizing a hydroxyl group-containing acrylate with a copolymerizable vinyl monomer copolymerizable with the hydroxyl group-containing acrylate.

[0122] Examples of hydroxyl group-containing acrylates include 2-hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate, hydroxybutyl (meth)acrylate, 2,2-dihydroxymethylbutyl (meth)acrylate, polyhydroxyalkyl maleate, polyhydroxyalkyl fumarate, etc. Preferably, 2-hydroxyethyl (meth)acrylate is used.

[0123] Examples of copolymerizable vinyl monomers include alkyl (meth)acrylates (C1-C12) such as methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, isopropyl (meth)acrylate, butyl (meth)acrylate, isobutyl (meth)acrylate, s-butyl (meth)acrylate, t-butyl (meth)acrylate, pentyl (meth)acrylate, isopentyl (meth)acrylate, hexyl (meth)acrylate, isononyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, cyclohexyl acrylate, and isobornyl (meth)acrylate, as well as aromatic vinyl monomers such as styrene, vinyl toluene, and α-methylstyrene. vinyl monomers, for example, vinyl cyanides such as (meth)acrylonitrile; carboxyl group-containing vinyl monomers such as (meth)acrylic acid, fumaric acid, maleic acid, and itaconic acid, or alkyl esters thereof; alkane polyol poly(meth)acrylates such as ethylene glycol di(meth)acrylate, butanediol di(meth)acrylate, hexanediol di(meth)acrylate, oligoethylene glycol di(meth)acrylate, trimethylolpropane di(meth)acrylate, and trimethylolpropane tri(meth)acrylate; and isocyanate group-containing vinyl monomers such as 3-(2-isocyanate-2-propyl)-α-methylstyrene.

[0124] The acrylic polyol can be obtained by copolymerizing these hydroxyl group-containing acrylates and copolymerizable vinyl monomers in the presence of a suitable solvent and a polymerization initiator.

[0125] The acrylic polyol may also include polysiloxane polyol and fluorine-containing polyol.

[0126] Illustrative examples of the polysiloxane polyol include acrylic polyols obtained by copolymerizing the acrylic polyols described above with a polysiloxane compound containing a vinyl group, such as γ-methacryloxypropyltrimethoxysilane, as a copolymerizable vinyl monomer.

[0127] Illustrative examples of the fluorine-containing polyol include acrylic polyols obtained by copolymerizing the acrylic polyols with a fluorine compound containing a vinyl group, such as tetrafluoroethylene or chlorotrifluoroethylene, as a copolymerizable vinyl monomer.

[0128] For example, the vinyl monomer-modified polyol can be obtained by reacting the high molecular weight polyol with a vinyl monomer such as the alkyl (meth)acrylate.

[0129] The above polyol components can be used alone or in combination of two or more kinds.

[0130] In addition, agent B may contain, as necessary, a urethanization catalyst, a hydrolysis inhibitor, an antifoaming agent, a surfactant, a slipping agent, a surface conditioner, an antioxidant, a weathering stabilizer, a pigment, a dye, a filler, a resin powder, etc. in an appropriate ratio.

[0131] Preferably, in the method for forming the two-component polyurethane composition as a coating material, for example, component A and component B are mixed, and the mixture is applied to an object to be coated by a known method and cured. This forms a coating material (coating layer). Such a coating material has excellent color fastness.

[0132] In a preferred technical means of the present application, the two-component polyurethane composition is used as a polyurethane paint to form a coating layer, which has excellent color fastness and high color stability under high temperature and high humidity conditions, and the color difference Δb of the coating after a humidity and heat durability test (2000 hours) is ≦1.2, and for example, Δb may be 1.15, 1.1, 1.05, 1.0, 0.9, 0.8, 0.7, 0.6, 0.5, etc., and more preferably is less than 1.2. [Effects of the Invention]

[0133] Compared to the related art, the embodiments of the present application have the following beneficial effects:

[0134] The isocyanate composition according to the present invention, through the design and control of effective factors, has excellent reactivity and can be used to produce high-performance polyurethane products. The isocyanate composition effectively improves the stability of polyurethane products, especially imparting excellent discoloration resistance to polyurethane coating materials, maintaining excellent color stability under high temperature and high humidity environments, and after 2000 hours of damp heat durability testing, the color difference Δb of the coating layer is 1.2 or less, significantly improving the yellowing resistance and appearance of the coating layer.

[0135] Other aspects will become apparent after reading and understanding the drawings and detailed description.

[0136] The drawings, which are included to provide a further understanding of the technical means of the present specification and constitute a part of the specification, are intended to interpret the technical means of the present specification together with the examples of the present application, and are not intended to limit the technical means of the present specification. [Brief explanation of the drawings]

[0137] [Figure 1] 1 is a flowchart of a method for producing an isocyanate composition according to one embodiment of the present application. DETAILED DESCRIPTION OF THE INVENTION

[0138] The technical solutions of the present application are further described below through specific embodiments. Those skilled in the art should understand that these examples are only for understanding the present application and should not be considered as specific limitations on the present application.

[0139] The components and performance measurement methods used in this application are as follows.

[0140] 1. Measurement of chlorine mass content (A value) in isocyanate composition: XRF test Equipment: Energy dispersive X-ray fluorescence spectrum (ED-XRF), Model number: MERAK-LE II Method: Standard addition method Principle and operation: Using a chromatographic peak-purity CCl4 standard as the Cl source and ethyl acetate as the diluent, the Cl element in the sample is excited by X-rays generated by an X-ray tube to generate characteristic X-ray fluorescence. The characteristic X-ray fluorescence intensity and element concentration are linearly related, and a standard curve is drawn. The extrapolated value is the Cl element content in the sample.

[0141] 2. Measurement of the mass content (B value) of chloroisocyanate in isocyanate composition: GCMS test Analysis was carried out by gas chromatography mass spectrometry under the following conditions, and the contents in this specification are normalized contents. Analytical instrument: Agilent 5977B GCMS Column: DB-5 column, specifications: 30 m x 0.25 mm x 0.25 μm Column oven temperature: Maintain at 50°C for 2 minutes, increase to 80°C at a rate of 5 mL / min, further increase to 280°C at a rate of 15 mL / min, and maintain for 10 minutes. Split ratio: Splitless Inlet temperature: 280℃ Detection temperature: 300℃ Carrier gas: Helium gas Carrier gas flow rate: 1 mL / min (constant flow rate) Sample injection volume: 1 μL Detection method: SIM selected ion monitoring mode (selected ions 160 / 126 for HDI, 146 / 112 for PDI, 254 / 220 for HMDI, 214 / 180 for IPDI)

[0142] 3. Measurement of mass percentage of isocyanate in isocyanate composition: Gas chromatography test The analysis was carried out by gas chromatography under the following conditions, and the contents in this specification are normalized contents. Analytical instrument: Agilent 7890B GC Column: DB-5 column, specifications: 30 m x 0.25 mm x 0.25 μm Column oven temperature: 50°C, maintained for 1 minute, heated to 300°C at a rate of 10°C / min, and maintained for 5 minutes. Split ratio: 30:1 Inlet temperature: 280℃ Detection temperature: 320℃ Carrier gas: Nitrogen gas Carrier gas flow rate: 1 mL / min (constant flow rate) Sample injection volume: 1 μL Detector: FID In the following specific embodiments of the present application, unless otherwise specified, "parts" and "%" are by mass.

[0143] Example 1 Regarding the HDI composition and its manufacturing method, the effectiveness factor E of the HDI composition is 4.70, and the manufacturing method thereof is shown in FIG. 1, and is specifically as follows:

[0144] In the phosgenation step, preheated vaporized 1,6-hexanediamine was introduced into the phosgenation reactor at a rate of 1,000 parts by mass / h, and phosgene was introduced at a rate of 5,112 parts by mass / h. The feed temperatures of the two feed streams were 310°C. After passing through the reaction zone of the phosgenation reactor, the streams were collected with chlorobenzene to obtain a reaction liquid. The feed pressure of 1,6-hexanediamine and phosgene was 0.25 MPa, the absolute pressure of the reaction zone was 0.09 MPa, slightly lower than atmospheric pressure, the feed molar ratio of phosgene to 1,6-hexanediamine was 6:1, the temperature of the reaction zone was 350°C, the flow rate was 70 m / s, the average contact time was 2 s, and the Reynolds number was 5,000. The stream was collected at the reactor outlet with cold chlorobenzene, and the temperature after collection was 140°C, obtaining a reaction liquid. As a result, 1,6-hexanediamine was reacted with phosgene to produce HDI, and a reaction product containing HDI was obtained.

[0145] In the removal step, the reaction product obtained in the phosgenation step was continuously supplied to a dephosgenation tower and a desolvation tower, and subjected to dephosgenation treatment and desolvation treatment, respectively, to produce 1,440 parts by mass of a crude HDI product.

[0146] In the separation step, the crude product obtained in the removal step was continuously transported to a short-path evaporator to obtain 1,418.7 parts by mass of an intermediate from which heavy components had been removed and 21.3 parts by mass of a primary heavy component.

[0147] In the heavy component recovery process, the primary heavy components are continuously transported to a secondary short-path evaporator to obtain 14.3 parts by mass of heavy component recovery material and 7.0 parts by mass of residual heavy components, and the heavy component recovery material is obtained by multiple circulations through the short-path evaporator. Next, the intermediate at a rate of 1418.7 parts by mass / h and the heavy component recovery material at a rate of 14.3 parts by mass / h are mixed to obtain a mixture, that is, the mass percentage of the heavy component recovery material in the mixture is 1%.

[0148] In the purification step, the mixture was continuously fed to a rectification column at a rate of 1,433 parts by mass / h. The rectification column was packed with packing equivalent to 25 theoretical plates, and then light components were removed from the top of the column. An HDI composition was collected from the middle of the column to obtain the target product.

[0149] The rectification conditions in the rectification column are as follows:

[0150] Bottom temperature: 120-130℃ Tower top temperature: 80-100℃ Top pressure: 10-50PaA Dwell time: 2-3 hours Top reflux ratio: 10 Amount collected in the rectification process: 1329 parts by mass / h.

[0151] This resulted in the HDI composition having a mass content of HDI >99%, a mass content of chlorine (A value) of 22.2 ppm, a mass content of chloroisocyanate CHI (B value) of 10 ppm, and an effectiveness factor E of 4.70.

[0152] Examples 2 to 5, Comparative Examples 1 to 2 Regarding the HDI composition and its manufacturing method, the effectiveness factor E of the HDI composition is shown in Table 1, and the manufacturing method flow is the same as that of Example 1, with only some process parameters being different, which are specifically shown in Table 1 (processes / parameters not shown in Table 1 are completely the same as those of Example 1). In Table 1, "phosgene molar ratio" indicates the molar amount of phosgene when 1,6-hexanediamine is taken as 1 mol in the phosgenation step, and "heavy component recovery material proportion" indicates the mass percentage of heavy components (recovered material) in the mixture in the heavy component recovery step.

[0153] [Table 1]

[0154] Examples 6 to 10, Comparative Examples 3 to 4 Regarding the PDI composition and its manufacturing method, the effectiveness factor E of the PDI composition is shown in Table 2, and the manufacturing flow is the same as that of Example 1, with only some differences in the process parameters, which are specifically shown in Table 2 (processes / parameters not shown in Table 2 are completely the same as those of Example 1). In Table 2, "phosgene molar ratio" indicates the molar amount of phosgene when 1,5-pentanediamine is taken as 1 mol in the phosgenation step, and "heavy component recovery material proportion" indicates the mass percentage of the heavy component (recovered material) in the mixture in the heavy component recovery step.

[0155] [Table 2]

[0156] Examples 11 to 15, Comparative Examples 5 to 6 Regarding the HMDI composition and its manufacturing method, the effectiveness factor E of the HMDI composition is shown in Table 3, and the manufacturing flow is the same as that of Example 1, with only some process parameters being different, which are specifically shown in Table 3 (processes / parameters not shown in Table 3 are completely the same as those of Example 1). In Table 3, "phosgene molar ratio" indicates the molar amount of phosgene when 4,4'-diaminodicyclohexylmethane is taken as 1 mol in the phosgenation step, and "heavy component recovery material proportion" indicates the mass percentage of heavy components (recovered material) in the mixture in the heavy component recovery step.

[0157] [Table 3]

[0158] Examples 16 to 20, Comparative Examples 7 to 8 Regarding the IPDI composition and its manufacturing method, the effectiveness factor E of the IPDI composition is shown in Table 4, and the manufacturing flow is the same as that of Example 1, with only some differences in the process parameters, which are specifically shown in Table 4 (processes / parameters not shown in Table 4 are completely the same as those of Example 1). In Table 4, "phosgene molar ratio" indicates the molar amount of phosgene when isophoronediamine is taken as 1 mol in the phosgenation step, and "heavy component recovery material ratio" indicates the mass percentage of the heavy component (recovered material) in the mixture in the heavy component recovery step.

[0159] [Table 4]

[0160] Examples 21 to 24 and Comparative Examples 9 to 12 Comparative Example 9 was prepared by the method of Example 8 of the related art CN101962348A. In this comparative example, HDI was prepared by thermal decomposition, and the product contained no chlorine or active ingredients. The heavy component recovery material of Example 1 was added to the product at a ratio of 4% (i.e., the mass percentage of heavy components in the resulting mixture was 4%) to obtain Example 21.

[0161] Similarly, as Comparative Example 10, PDI was produced using the method of Example 1 of the related art CN114105825A, and the heavy component recovery material of Example 6 was added to the product at a ratio of 4% (i.e., the mass percentage of heavy components in the resulting mixture was 4%) to obtain Example 22.

[0162] As Comparative Example 11, HMDI was produced using the method of Example 4 of the related art CN101234998A, and the heavy component recovery material of Example 11 was added to the product at a ratio of 4% (i.e., the mass percentage of heavy components in the resulting mixture was 4%) to obtain Example 23.

[0163] As Comparative Example 12, IPDI was produced using the method of Example 1 of the related art CN114507161A, and the heavy component recovery material of Example 16 was added to the product at a ratio of 4% (i.e., the mass percentage of heavy components in the resulting mixture was 4%) to obtain Example 24.

[0164] Application Examples The two-component polyurethane composition is specifically a two-component polyurethane coating material (paint) containing an A-component and a B-component.

[0165] Specifically, in this application example, two types of Agent A, designated Agent A-1 and Agent A-2, were provided, and each was combined with Agent B to form a two-component polyurethane coating material. The compounding method was as follows:

[0166] (1) To produce Agent A-1, 413.7 parts by mass of the HDI composition (37.7 parts by mass relative to the mass of the PDI composition, 39.9 parts by mass relative to the mass of the HMDI composition, and 39.9 parts by mass relative to the mass of the IPDI composition) were mixed with 36.7 parts of trimethylolpropane and reacted for 6 hours at 70°C under a nitrogen atmosphere. The reaction solution obtained by the reaction was distilled using a thin-film distillation apparatus to remove unreacted isocyanate, thereby obtaining a modified isocyanate composition. The modified isocyanate composition contained urethane groups obtained by the reaction of isocyanate with trimethylolpropane, and the aforementioned isocyanate compositions were the isocyanate compositions of Examples 1 to 24 and Comparative Examples 1 to 12, respectively. Ethyl acetate was added to the modified isocyanate composition so that the solid content was 75 wt. % to produce a polyisocyanate component (A-1), and the NCO group content in the polyisocyanate component was 11.6 wt. %.

[0167] (2) To produce Agent A-2, 2 parts of 1,3-butanediol were added to 100 parts of the HDI composition (37.7 parts by mass relative to the mass of the PDI composition, 39.9 parts by mass relative to the mass of the HMDI composition, and 39.9 parts by mass relative to the mass of IPDI), and the mixture was heated to 75°C under a nitrogen atmosphere to carry out a urethane reaction for 2 hours, resulting in an equivalent ratio (NCO / OH) of the isocyanate groups in the isocyanate composition to the hydroxyl groups in the 1,3-butanediol of 24. Subsequently, at the same temperature, 0.1 phr (0.037 phr in terms of solids) of a tetrabutylammonium hydroxide solution (37% methanol solution) was added as an isocyanuration catalyst, and the mixture was allowed to react for 4 hours to complete the isocyanuration reaction. The unreacted isocyanate was removed from the resulting reaction solution using a thin-film distillation apparatus (temperature 150°C, vacuum degree 50 Pa) (distillation yield 60 wt.%), thereby obtaining a modified isocyanate composition. The modified isocyanate composition contained an isocyanurate group of an isocyanate trimer, and the above-mentioned isocyanate compositions were the isocyanate compositions of Examples 1 to 24 and Comparative Examples 1 to 12, respectively. Ethyl acetate was added to the modified isocyanate composition so that the solid content was 75 wt. % to produce a polyisocyanate component (Agent A-2).

[0168] (3) To produce Agent B, 40 parts by mass of a fluorine-containing polyol (ZEFFLE GK-570 manufactured by Daikin Industries Ltd., solids hydroxyl value: 64 mg KOH / g, solvent: butyl acetate), 52.5 parts of titanium oxide (CR93 manufactured by Ishihara Sangyo Kaisha, Ltd.), 33.8 parts of butyl acetate, and 110 parts of glass beads with a diameter of 2 mm were stirred in a paint shaker for 2 hours, and the glass beads were then filtered off. Further, butyl acetate was added so that the solids concentration became 58 wt.%, and Agent B with a titanium oxide content of 45 wt.% was obtained.

[0169] (4) To prepare the two-component polyurethane coating material, the obtained Agent A (Agent A-1 or Agent A-2) and Agent B were mixed to prepare a mixed solution so that the equivalent ratio (NCO / OH) of the isocyanate group to the hydroxyl group was 1.0, and then butyl acetate was added to the mixed solution so that the NV value (mass of coating components, solid content) was 60 wt.% to obtain the two-component polyurethane coating material.

[0170] Performance evaluation: The two-component polyurethane coating material to be measured was applied to the surface of a polyethylene terephthalate (PET) substrate and cured by heating at 120°C for 2 minutes. The PET substrate with the mixed liquid applied was then cured at 60°C for 2 days, forming a coating layer approximately 15 μm thick on the PET substrate.

[0171] The weather resistance of the coating layer (color difference of the coating layer in a moist heat test) was measured. Specifically, the initial b value (b1, initial value) of the coating layer was measured using a color difference meter (3nh NR10QC), and then the sample to which the coating layer was applied was placed in a thermo-hygrostat (high-iron device) and held at 85°C and 85% relative humidity for 2000 hours. The b value (b2) of the sample after the 2000-hour moist heat durability test was measured using the same method as above, and the color difference Δb of the coating layer before and after the moist heat test was calculated as Δb = |b2 - b1|. The results are shown in Tables 5 to 8.

[0172] [Table 5]

[0173] [Table 6]

[0174] [Table 7]

[0175] [Table 8]

[0176] As can be seen from the above performance test data, by controlling the effectiveness factor of the isocyanate composition within the range of 3.70 to 4.70, the two-component polyurethane coating material produced in this application has excellent discoloration resistance and high color stability under high temperature and high humidity conditions. After the humidity and heat durability test (2000 hours), the color difference Δb of the coating layer is less than 1.2, and is as low as 0.98 to 1.19.

[0177] The applicant declares that the present application has described the isocyanate composition, its preparation method and application through the above examples, but this does not mean that the present application is not limited to the above process steps, i.e., that the present application cannot be carried out without relying on the above process steps. Those skilled in the art should understand that any modifications to the present application, equivalent replacement of raw materials used in the present application, addition of auxiliary components, selection of specific methods, etc., are all within the scope of protection and disclosure of the present application. [Explanation of symbols]

[0178] 10-Phosgenation process 20-Removal process 30-Separation process 40-Heavy component recovery process 50-Purification process

Claims

1. an isocyanate composition, wherein the isocyanate composition has an effectiveness factor of 3.70 to 4.70; The formula for calculating the effectiveness factor is shown in Formula I: [Equation 2] E is the effectiveness factor, A is the mass content of chlorine in the isocyanate composition, B is the mass content of chloroisocyanate in the isocyanate composition, M Ｃｌ is the relative atomic mass of chlorine, M Ｂ is the relative molecular mass of said chloroisocyanate.

2. The isocyanate composition of claim 1 , wherein the isocyanate is a diisocyanate.

3. The isocyanate composition according to claim 2, wherein the diisocyanate comprises any one or a combination of at least two of pentamethylene diisocyanate, hexamethylene diisocyanate, dicyclohexylmethane diisocyanate, and isophorone diisocyanate.

4. The isocyanate composition according to any one of claims 1 to 3, wherein the mass percentage of the isocyanate in the isocyanate composition is 97% or more.

5. The substance corresponding to the effective factor includes any one or a combination of at least two of the following compounds: 【Chemistry 14】 R is a divalent group obtained by removing an NCO group from an isocyanate, Preferably, R is 【Chemistry 15】 The isocyanate composition according to any one of claims 1 to 4, wherein the wavy line indicates a linking site of the group.

6. The chloroisocyanate is a compound in which one NCO group in an isocyanate is substituted with chlorine, Preferably, the chloroisocyanate is 【Chemistry 16】 The isocyanate composition according to any one of claims 1 to 5, comprising any one or a combination of at least two of the following:

7. The A is obtained by measurement using X-ray fluorescence analysis, The isocyanate composition according to any one of claims 1 to 6, wherein B is preferably obtained by measurement using chromatography-mass spectrometry, and more preferably obtained by measurement using gas chromatography-mass spectrometry.

8. A method for producing the isocyanate composition according to any one of claims 1 to 7, comprising the step of reacting an amine compound with phosgene to obtain the isocyanate composition.

9. Step (1) of reacting an amine compound with phosgene to obtain a reaction product; Step (2) of subjecting the reaction product obtained in step (1) to a removal treatment including a phosgen removal treatment and / or a solvent removal treatment to obtain a crude product; and (3) sequentially separating and purifying the crude product obtained in step (2) to obtain the isocyanate composition.

10. 10. The method according to claim 9, wherein in step (3), a heavy component and an intermediate are obtained by the separation, and a mixture of the intermediate and the heavy component is purified to obtain the isocyanate composition, and a mass percentage of the heavy component in the mixture is 1 to 10%.

11. The method of claim 10, wherein the purification method is rectification.

12. A modified isocyanate composition obtained by modifying the isocyanate composition according to any one of claims 1 to 7, The modified isocyanate composition contains any one or a combination of at least two of (a) an isocyanurate group, (b) a uretdione group, (c) a biuret group, (d) a urethane group, (e) a urea group, (f) an iminooxadiazinedione group, (g) an allophanate group, (h) a uretonimine group, and (i) a carbodiimide group.

13. An isocyanate-based polymer, the polymer being obtained by reacting an isocyanate-based substance with an active hydrogen group-containing substance, the isocyanate-based substance including at least one of the isocyanate composition according to any one of claims 1 to 7 and the modified isocyanate composition according to claim 12.

14. A two-component polyurethane composition comprising Part A and Part B, The component A comprises the isocyanate composition according to any one of claims 1 to 7 and / or the modified isocyanate composition according to claim 12, The component B is a two-component polyurethane composition containing an active hydrogen group-containing substance.

15. The modified isocyanate composition contains (a) an isocyanurate group and / or (d) a urethane group, The two-component polyurethane composition of claim 14, wherein the B part preferably comprises a polyol.

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