Resin composition and cured product thereof

Abstract

To raise the glass transition temperature of a cured product.　A resin composition according to an embodiment comprises a compound represented by formula (1) and a compound represented by formula (2). In formula (1), R1 represents a divalent hydrocarbon group optionally including a heteroatom, R2 and R3 each independently represent a C1-10 alkanediyl group, R4 and R5 each independently represent a hydrogen atom or a methyl group, R6 and R7 each independently represent a methyl group or an ethyl group, and p and q each independently represent an integer of 0-2. In formula (2), R8 represents a divalent hydrocarbon group optionally including a heteroatom.

Description

Resin composition and cured product thereof

[0001] Embodiments of the present invention relate to a resin composition containing benzoxazine and biscitraconimide, and a cured product thereof.

[0002] Benzoxazines are compounds containing a benzoxazine ring formed by the condensation reaction of phenols, amines, and formaldehyde. Benzoxazines are thermosetting monomers that harden when heated, as the benzoxazine ring undergoes ring-opening polymerization.

[0003] For example, Patent Document 1 discloses a benzoxazine having two benzoxazine rings in one molecule, obtained by condensing phenol with 4,4'-diaminodiphenylmethane and paraformaldehyde. Patent Document 2 discloses a benzoxazine having benzoxazine rings at the 3 and 4' positions of a diphenyl ether group, obtained by condensing phenol with 3,4'-diaminodiphenyl ether and formaldehyde.

[0004] On the other hand, it is known that biscitraconimide is used as a printed circuit board material, for example. Biscitraconimide does not heat-cur on its own, but it is known that it can be heat-cured by adding a crosslinking agent (curing agent).

[0005] For example, Patent Document 3 describes that a resin material containing a maleimide compound having a skeleton derived from a dimer amine may have benzoxazine added as a curing agent, and that the maleimide compound may also be a citraconimide compound. Patent Document 4 describes that a lithography film-forming material containing a polycitraconimide compound may contain benzoxazine as a crosslinking agent.

[0006] Japanese Patent Publication No. 4647398, Japanese Unexamined Patent Publication No. 2018-184533, International Publication No. 2020 / 045408, International Publication No. 2020 / 004316

[0007] Some benzoxazines have an allyl group at the molecular terminal. Such a terminal unsaturated hydrocarbon group does not react by the thermal ring-opening polymerization of benzoxazine, but can react with other polymerizable monomers. When such a benzoxazine having a terminal unsaturated hydrocarbon group is used, for example, as a printed circuit board material, it is required to increase the glass transition temperature of the cured product.

[0008] An embodiment of the present invention aims to improve the glass transition temperature of a cured product in a resin composition containing a benzoxazine having a terminal unsaturated hydrocarbon group.

[0009] The present invention includes the following embodiments. [1] A compound represented by the following general formula (1) and a compound represented by the following general formula (2), In formula (1), R １ represents a divalent hydrocarbon group having 1 to 100 carbon atoms which may contain a hetero atom, R ２ and R ３ each independently represent an alkanediyl group having 1 to 10 carbon atoms, R ４ and R ５ each independently represent a hydrogen atom or a methyl group, R ６ and R ７ each independently represent a methyl group or an ethyl group, p and q each independently represent an integer of 0 to 2, In formula (2), R ８ represents a divalent hydrocarbon group having 1 to 100 carbon atoms which may contain a hetero atom, a resin composition.

[0010] [2] The resin composition according to [1], wherein R １ in the formula (1) is a divalent aromatic ring-containing hydrocarbon group having 6 to 50 carbon atoms which may contain a hetero atom. [3] The compound represented by the formula (1) is represented by the following general formula (1A), In formula (1A), R １１ represents a single bond, -CH ２ -, -CH(CH ３ ) -, -C(CH ３ ) ２ -, or -O -, R １２ and R １３Each independently represents a methyl group or an ethyl group, and s and t each independently represent an integer from 0 to 4, R ２ and R ３ Each of these independently represents an alkanediyl group having 1 to 10 carbon atoms, R ４ and R ５ Each of these independently represents a hydrogen atom or a methyl group, R ６ and R ７ The resin composition according to [1], wherein each represents independently a methyl group or an ethyl group, and p and q each represent independently an integer from 0 to 2.

[0011] [4] R in formula (2) ８ A resin composition according to any one of [1] to [3], wherein is a divalent aromatic ring-containing hydrocarbon group having 6 to 50 carbon atoms, which may contain a heteroatom. [5] The compound represented by formula (2) is represented by the following general formula (2A), In formula (2A), R ２１ This is a single bond, -CH ２ -, -CH(CH ３ )-,-C(CH ３ ) ２ -, -O-, or a group represented by the following formula (21A), R ２２ and R ２３ Each independently represents a methyl group or an ethyl group, and each independently represents an integer from 0 to 4. In formula (21A), R ２４ and R ２５ Each is independently -CH ２ -, -CH(CH ３ )-,-C(CH ３ ) ２ A resin composition according to any one of items [1] to [3], representing - or -O-.

[0012] [6] A resin composition according to any one of [1] to [5] used as a printed circuit board material. [7] A cured product obtained by curing a resin composition according to any one of [1] to [6].

[0013] According to embodiments of the present invention, the glass transition temperature of a cured product can be improved in a resin composition containing benzoxazine having terminally unsaturated hydrocarbon groups.

[0014] The resin composition according to this embodiment contains a compound represented by the following general formula (1) (hereinafter referred to as compound (1)). Compound (1) is a compound composed of one molecule of diamine, two molecules of phenols, and four molecules of formaldehyde, and has two benzoxazine rings in its molecule.

[0015] In equation (1), R １ R represents a divalent hydrocarbon group having 1 to 100 carbon atoms, which may contain heteroatoms. １ The number of carbon atoms in the hydrocarbon group is preferably 2 to 70, more preferably 3 to 50, more preferably 5 to 30, and even more preferably 6 to 20. Examples of heteroatoms include oxygen atoms, nitrogen atoms, sulfur atoms, fluorine atoms, silicon atoms, etc., and oxygen atoms are preferred, but R １ It is preferable that it does not contain heteroatoms.

[0016] R １ The hydrocarbon group preferably contains an aromatic ring (i.e., is an aromatic ring-containing hydrocarbon group), more preferably contains a benzene ring, and even more preferably contains two or three benzene rings. Therefore, R １ The number of carbon atoms in the hydrocarbon group is more preferably 6 to 50, more preferably 12 to 30, and even more preferably 12 to 20.

[0017] In equation (1), R ２ and R ３ Each of these independently represents an alkanediyl group (also called an alkylene group) having 1 to 10 carbon atoms. The alkanediyl group may be a straight chain or a branched chain. Preferably, R ２ and R ３ Each of these is independently an alkanediyl group having 1 to 5 carbon atoms, more preferably an alkanediyl group having 1 to 3 carbon atoms, and more preferably an ethylene group (-CH ２ CH ２ -) or methylene group (-CH ２ -) and more preferably a methylene group. In formula (1), R ４ and R ５Each of these independently represents a hydrogen atom or a methyl group, and more preferably a hydrogen atom. ２ C=CR ４ R ２ - and H ２ C=CR ５ R ３ The unsaturated hydrocarbon group represented by - has an allyl group (H) at its terminal end. ２ C = CH - CH ２ -) or methallyl group (H ２ C = C(CH) ３ ) - CH ２ CR ４ or CR ５ It is preferable that the carbon adjacent to it is a methylene group.

[0018] In equation (1), R ６ and R ７ Each independently represents a methyl group or an ethyl group, more preferably a methyl group. In formula (1), p and q each independently represent an integer from 0 to 2, more preferably independently 0 or 1, and even more preferably 0.

[0019] In equation (1), H ２ C=CR ４ R ２ - and H ２ C=CR ５ R ３ An unsaturated hydrocarbon group represented by - and R ６ and R ７ With respect to the substituents represented by , it is preferable that their bonding positions to the benzene ring be set as follows: One unsaturated hydrocarbon group and 0 to 2 substituents are bonded to the benzene ring, provided that at least one of the ortho or para positions relative to the oxygen atom bonded to the benzene ring is unsubstituted (i.e., a hydrogen atom). Preferably, the unsaturated hydrocarbon group is bonded to the ortho position relative to the oxygen atom.

[0020] Compound (1) is more preferably represented by the following general formula (1A).

[0021] In equation (1A), R １１ This is a single bond, -CH ２-, -CH(CH ３ ), -C(CH ３ ) ２ -, or -O-. R １１ is preferably a single bond, -CH ２ -, or -O-, more preferably a single bond or -CH ２ -. The bonding position of R １１ to the two benzene rings is preferably the 4,4'-position, 3,4'-position, or 3,3'-position as the bonding position of the benzoxazine ring to the group represented by Ph-R １１ -Ph (where Ph represents a benzene ring which may have a substituent R １２ or R １３ ).

[0022] In formula (1A), R １２ and R １３ each independently represent a methyl group or an ethyl group, more preferably a methyl group. When R １２ and R １３ are present in plurality in one molecule, they may be the same or different. s and t each independently represent an integer from 0 to 4, more preferably an integer from 0 to 2, still more preferably 0 or 1.

[0023] In formula (1A), R ２ , R ３ , R ４ , R ５ , R ６ , R ７ , p and q are the same as R ２ , R ３ , R ４ , R ５ , R ６ , R ７ , p and q in formula (1), respectively.

[0024] In one embodiment, the compound (1) is preferably represented by the following general formula (1B). In formula (1B), R １１ , R １２ , R １３ , R ２ , R ３ , R ４ , R ５s and t are R in equation (1A), respectively. １１ , R １２ , R １３ , R ２ , R ３ , R ４ , R ５ , s and t are the same.

[0025] In one embodiment, compound (1) may be a compound represented by the following general formula (1C). In equation (1C), R ２ , R ３ , R ４ and R ５ These are R in equation (1A), respectively. ２ , R ３ , R ４ and R ５ It is the same as this.

[0026] In one embodiment, compound (1) may be a compound represented by the following general formula (1D). In equation (1D), R １２ , R １３ , R ２ , R ３ , R ４ and R ５ These are R in equation (1A), respectively. １２ , R １３ , R ２ , R ３ , R ４ and R ５ It is the same as this.

[0027] The method for producing compound (1) is not particularly limited, and can be obtained, for example, by condensing phenols, diamines, and formaldehyde. More specifically, in the presence of a solvent, phenols represented by the following formula (3), diamines represented by the following formula (4), and formaldehyde (e.g., paraformaldehyde, i.e., (HClO)) ｎ One method involves stirring and mixing the two components and then carrying out a dehydration condensation reaction under heating. After the condensation reaction, the product may be purified by liquid-liquid washing, recrystallization, column purification, etc.

[0028] In equation (3), R １４ H in formula (1) above ２C=CR ４ R ２ - or H ２ C=CR ５ R ３ - is the same as R １５ R in equation (1) above ６ or R ７ This is the same as, and r is the same as p or q in equation (1). In equation (4), R １ R in equation (1) above １ It is the same as this.

[0029] Examples of solvents include organic solvents capable of dissolving benzoxazine, such as toluene, xylene, cumene, monochlorobenzene, methyl ethyl ketone, ethyl acetate, butyl acetate, chloroform, dichloromethane, THF, dioxane, and dimethylformamide. These may be used individually or in combination of two or more.

[0030] Regarding the ratio of phenols, diamines, and formaldehyde, since the target product represented by formula (1) is obtained by reacting 2 moles of phenols and 4 moles of formaldehyde with 1 mole of diamine, the amount of charge can be set based on this. For example, it is preferable to charge 2.0 to 2.5 moles of phenols per mole of diamine, more preferably 2.0 to 2.2 moles, and even more preferably 2.0 to 2.1 moles. It is preferable to charge 3.9 to 5.0 moles of formaldehyde per mole of diamine, more preferably 4.0 to 4.5 moles, and even more preferably 4.0 to 4.3 moles.

[0031] The reaction products obtained by the condensation reaction described above typically include compound (1) as the main product, as well as by-products such as a one-ring open compound in which one of the two benzoxazine rings of compound (1) is not ring-closed, and polymers (including oligomers) of compound (1). The resin composition according to this embodiment may include compound (1) and a by-product corresponding to compound (1) as benzoxazine. That is, compound (1) and the by-product (as an optional component) corresponding to compound (1) are collectively referred to as benzoxazine, and the resin composition according to this embodiment contains this benzoxazine. The proportion of compound (1) in the benzoxazine is not particularly limited, but is preferably 40% or more, more preferably 45% or more, and even more preferably 50% or more. There is no particular upper limit, but the proportion of compound (1) is usually 80% or less, and may be 70% or less. Here, the proportion of compound (1) is the ratio of peak areas obtained by GPC analysis.

[0032] The resin composition according to this embodiment contains a compound represented by the following general formula (2) (hereinafter referred to as compound (2)). Compound (2) is a biscitraconimide having two citraconimide groups.

[0033] In equation (2), R ８ R represents a divalent hydrocarbon group having 1 to 100 carbon atoms, which may contain heteroatoms. ８ The number of carbon atoms in the hydrocarbon group is preferably 2 to 70, more preferably 3 to 50, more preferably 5 to 30, and even more preferably 6 to 20. Examples of heteroatoms include oxygen atoms, nitrogen atoms, sulfur atoms, fluorine atoms, silicon atoms, etc., and oxygen atoms are preferred, but R ８ It is preferable that it does not contain heteroatoms.

[0034] R ８ The hydrocarbon group preferably contains an aromatic ring (i.e., is an aromatic ring-containing hydrocarbon group), more preferably contains a benzene ring, and even more preferably contains two or three benzene rings. Therefore, R ８The number of carbon atoms in the hydrocarbon group is more preferably 6 to 50, more preferably 12 to 30, and even more preferably 12 to 20.

[0035] Compound (2) is more preferably represented by the following general formula (2A).

[0036] In equation (2A), R ２１ This is a single bond, -CH ２ -, -CH(CH ３ )-,-C(CH ３ ) ２ This represents -, -O-, or the group represented by the following formula (21A). In equation (21A), R ２４ and R ２５ Each is independently -CH ２ -, -CH(CH ３ )-,-C(CH ３ ) ２ It represents - or -O-.

[0037] In equation (2A), R ２１ Preferably, a single bond, -CH ２ -, -O-, or a group represented by formula (21A), more preferably a single bond or -CH ２ - is the case. R for the two benzene rings ２１ The binding site is Ph-R ２１ - A group represented by Ph (where Ph is substituent R) ２２ or R ２３ The benzene ring may have a benzene ring. The preferred bond position of the citraconimide group to the benzene ring is the 4,4', 3,4', or 3,3' position.

[0038] In equation (21A), R ２４ and R ２５ Preferably, each is independently -CH ２ -, -CH(CH ３ )-, or-C(CH ３ ) ２ - and more preferably -C(CH ３ ) ２ - is the case. R relative to the benzene ring. ２４ and R ２５The bonding position is preferably the meta or para position, and more preferably the meta position.

[0039] In equation (2A), R ２２ and R ２３ Each of these independently represents either a methyl group or an ethyl group, and more preferably a methyl group. ２２ and R ２３ If multiple of each are present in a single molecule, they may be the same or different. u and v each independently represent integers from 0 to 4, more preferably integers from 0 to 2, and even more preferably 0 or 1.

[0040] In one embodiment, compound (2) is preferably represented by the following general formula (2B). In equation (2B), R ２１ , R ２２ , R ２３ u and v are R in equation (2A), respectively. ２１ , R ２２ , R ２３ , is the same as u and v.

[0041] The method for producing compound (2) is not particularly limited, and for example, it can be obtained by dehydration condensation reaction of citraconic anhydride and a diamine.

[0042] The resin composition according to the embodiment is a thermosetting resin composition comprising compound (1) and compound (2). Specifically, compound (1) has a benzoxazine ring and is cured (thermosetting) by thermal ring-opening polymerization as a monomer. Also, the H of compound (1) ２ C=CR ４ R ２ - and H ２ C=CR ５ R ３The unsaturated hydrocarbon group represented by - reacts with the citraconimide of compound (2), causing compound (2) to thermally cure together with compound (1). Therefore, the cured product of the resin composition according to the embodiment is expected to have an improved glass transition temperature compared to when compound (1) is cured alone. Furthermore, in the resin composition according to the embodiment, compound (2), which is biscitraconimide, has higher solvent solubility than its similar substance, bismaleimide. In addition, the resin composition according to the embodiment has high reactivity in the curing reaction and excellent moldability of the cured product. Moreover, the resin composition according to the embodiment has a low water absorption rate and excellent low water absorption properties.

[0043] In the resin composition according to the embodiment, the mixing ratio of compound (1) and compound (2) is not particularly limited, but in one embodiment it may be set as follows. Since compound (1) is usually produced together with by-products such as ring-opened products and polymers as described above, it is preferable to set the mixing ratio with compound (2) as a benzoxazine containing these by-products. That is, the mass ratio of benzoxazine (BZO) consisting of compound (1) and its by-products to biscitraconimide (CI) of compound (2), i.e., the mass ratio of BZO to CI, BZO / CI, is preferably 0.35 to 4.0, more preferably 0.4 to 3.0, and more preferably 0.8 to 2.0. By having a BZO / CI of 4.0 or less, the effect of improving the glass transition temperature of the cured product can be enhanced. By having a BZO / CI of 0.35 or more, the moldability of the cured product can be improved.

[0044] The resin composition according to the embodiment may consist only of the benzoxazine (BZO) containing compound (1) and biscitraconimide (CI) of compound (2), or it may contain, for example, other thermosetting resins and / or thermoplastic resins together with BZO and CI. The resin composition may also contain various known additives such as solvents, catalysts, crosslinking agents, curing accelerators, colorants, radical polymerization initiators, leveling agents, flame retardants, antioxidants, and inorganic fillers.

[0045] In the resin composition, the total amount of benzoxazine (BZO) and biscitraconimide (CI), excluding the solvent, is preferably 50% by mass or more, more preferably 70% by mass or more, and even more preferably 80% by mass or more. In one embodiment, the resin composition is a resin solution containing a solvent. In this case, the solvent content in the resin composition is not particularly limited and may be, for example, 30 to 70% by mass or 40 to 60% by mass.

[0046] Examples of solvents included in the resin composition are organic solvents capable of dissolving benzoxazine and biscitraconimide, such as toluene, xylene, cumene, monochlorobenzene, methyl ethyl ketone, ethyl acetate, butyl acetate, chloroform, dichloromethane, THF, dioxane, and dimethylformamide. These may be used individually or in combination of two or more. Aromatic hydrocarbon solvents and ketone solvents are preferred as solvents. Furthermore, from the viewpoint of ease of removal during curing by evaporation, non-halogen solvents with a boiling point of 150°C or lower are preferred.

[0047] Examples of catalysts included in the resin composition include imidazole-based catalysts such as 2-ethyl-4-methylimidazole, 2-phenyl-4-methylimidazole, and 1,2-dimethylimidazole, and organophosphorus-based catalysts such as triphenylphosphine and tributylphosphine.

[0048] The cured product according to this embodiment is obtained by curing the above resin composition, which is usually cured by heating. The curing conditions are not particularly limited, and for example, heating may be performed at 150°C to 250°C for 30 to 180 minutes. If the resin composition contains a solvent, the solvent may be evaporated by heating, and then the temperature may be further increased to perform thermal curing.

[0049] The resin composition according to this embodiment can be used in a variety of applications, such as electrical insulating materials and matrix resins for composite materials.

[0050] In one embodiment, the resin composition is preferably used as a printed circuit board material. That is, the printed circuit board material according to one embodiment includes a resin composition containing compound (1) and compound (2). Using this printed circuit board material, printed circuit boards such as printed wiring boards and printed circuit boards according to one embodiment can be manufactured.

[0051] Examples of printed circuit board materials include rigid printed circuit board materials for manufacturing single-sided boards, double-sided boards, multilayer boards, and build-up boards, as well as flexible printed circuit board materials for manufacturing film-like or sheet-like flexible printed circuit boards.

[0052] The present invention will be described in more detail below based on examples and comparative examples, but it is not limited thereto.

[0053] <Measurement and Evaluation Method> [Purity of the main product in benzoxazine] For BZO-4 from Synthesis Examples 1-2 and Comparative Synthesis Examples 3-4, the reaction product was dissolved in THF to a concentration of approximately 0.2 mg / ml, and GPC was measured using gel permeation chromatography (GPC) (Prominence, Shimadzu Corporation) with four columns (Shodex GPC columns KF-601, KF-602, KF-603, KF-604, manufactured by Resonaq Corporation) lined up with polystyrene gel as the packing material. The measurement conditions were a column oven temperature of 40°C and a flow rate of 0.6 ml / min, and a differential refractive index detector (Shodex RI-504, manufactured by Resonaq Corporation) was used. From the obtained chromatogram, the peaks originating from the solvent (toluene) were removed, and the purity of the main product was calculated as the ratio (%) of the peak areas.

[0054] [Solubility] Each component was mixed according to the formulations shown in Tables 1 and 2 (units are in grams). The mixture that dissolved uniformly at room temperature was classified as "A", the mixture that dissolved uniformly after heating to 50°C was classified as "B", and the mixture that still contained insoluble matter even after heating to 50°C was classified as "C".

[0055] [Moldability] For the examples and comparative examples in which the solubility evaluation above was A or B, the resin composition prepared with the formulation (g) shown in Table 1 or Table 2 was placed in an aluminum cup with an upper diameter of 60 mm, a lower diameter of 54 mm, and a depth of 16 mm, and the solvent was removed by heating on a hot plate at 120°C for 1 hour. The hot plate was then heated to 250°C for 1 hour to perform heat curing, and a flat plate was produced by allowing it to cool to room temperature. Plates with significant appearance defects such as bubbles, cracks, and curing defects were classified as "B", while those with minor or no such appearance defects were classified as "A".

[0056] [Glass Transition Temperature (Tg)] For the examples and comparative examples where the solubility evaluation above was A or B, the resin composition prepared with the formulation (g) shown in Table 1 or Table 2 was placed in an aluminum cup with an upper diameter of 60 mm, a lower diameter of 54 mm, and a depth of 16 mm, and heated on a hot plate at 120°C for 1 hour to remove the solvent. The hot plate was then heated to 250°C for 1 hour to perform thermosetting, and a flat plate was produced by allowing it to cool to room temperature. For those where the moldability evaluation above was A, a test piece with a width of 5 mm, a thickness of approximately 1 mm, and a length of 30 mm was prepared from the obtained flat plate. Next, the glass transition temperature was measured using a dynamic viscoelasticity measuring device: Rheogel-E4000 (manufactured by UBM Co., Ltd.). For the test piece, the temperature at which the loss tangent (tanδ), measured under conditions of tensile sine wave, dynamic strain of 5 μm, frequency of 1 Hz, and heating rate of 3°C / min, took its maximum value was determined as the glass transition temperature.

[0057] [Water Absorption Rate] Test specimens similar to those used for measuring the glass transition temperature in Examples 1 to 11 and Comparative Example 5 were prepared, and the percentage increase in mass (%) before and after immersion in water at 25°C for 24 hours was measured and calculated as the 25°C water absorption rate. Similarly, the percentage increase in mass (%) before and after immersion in water at 40°C for 24 hours was measured and calculated as the 40°C water absorption rate.

[0058] <Synthesis Example 1> In a 5 L reactor equipped with a condenser, a Dean-Stark apparatus, and a stirrer, 521.0 g of 4,4'-diaminodiphenylmethane, 705.2 g of 2-allylphenol, and 1569.3 g of toluene were added and dissolved at 75°C. Next, 343.1 g of 92% by mass paraformaldehyde was added in five portions, and the reaction mixture was heated to remove the water produced by the dehydration condensation reaction. The reaction mixture was further heated to 105-110°C and the reaction was continued for 6 hours. After the reaction mixture was cooled to room temperature, 301.7 g of toluene was added to dilute it. 784.6 g of 10% by mass sodium hydroxide aqueous solution was added, stirred for 15 minutes, and allowed to stand to separate and remove the aqueous layer. This procedure was repeated twice. Furthermore, 627.7 g of water and 156.9 g of isopropyl alcohol (IPA) were added to the resulting organic layer, stirred for 15 minutes, and allowed to stand to separate and remove the aqueous layer. This procedure was repeated five times. The water and IPA from the obtained organic layer were removed by vacuum distillation using a rotary evaporator to obtain a toluene solution (BZO1) containing the reaction product at a concentration of 49.8% by mass. The obtained reaction product was a benzoxazine containing the compound represented by the following formula as the main product, and the purity of the main product by GPC analysis was 56.2%.

[0059] <Synthesis Example 2> In a 5 L reactor equipped with a condenser, a Dean-Stark apparatus, and a stirrer, 436.9 g of 4,4'-diamino-2,2'-dimethylbiphenyl, 552.0 g of 2-allylphenol, and 1257.6 g of toluene were added and dissolved at 75°C. Next, 268.7 g of 92% by mass paraformaldehyde was added in five portions, and the reaction mixture was heated to remove the water produced by the dehydration condensation reaction. The reaction mixture was further heated to 105-110°C and the reaction was continued for 6 hours. After the reaction mixture was cooled to room temperature, 168.4 g of toluene was added to dilute it. 503.0 g of 10% by mass aqueous sodium hydroxide solution and 125.8 g of IPA were added, and the mixture was stirred for 15 minutes. After standing, the aqueous layer was separated and removed twice, and then 179.2 g of toluene was added to the resulting organic layer to dilute it. 503.0 g of water and 125.8 g of IPA were added to the mixture, stirred for 15 minutes, and allowed to stand. This process of separating and removing the aqueous layer was repeated five times. The water and IPA from the resulting organic layer were removed by vacuum distillation to obtain a toluene solution (BZO2) containing the reaction product at a concentration of 51.4% by mass. The resulting reaction product was a benzoxazine containing the compound represented by the following formula as the main product, and the purity of the main product by GPC analysis was 61.7%.

[0060] <Synthesis Example 3> In a 500 mL reactor equipped with a condenser, a Dean-Stark apparatus, and a stirrer, 149.2 g of anhydrous citraconic acid and 845.5 g of toluene were added and mixed. A solution of 120.0 g of 4,4'-diaminodiphenylmethane dissolved in 360.0 g of N-methylpyrrolidone (NMP) was added dropwise and the mixture was reacted for 30 minutes. After adding 11.5 g of p-toluenesulfonic acid monohydrate to the reaction solution, the reaction solution was heated and the reaction was continued at 105-110°C for 4 hours while distilling off the water produced by the dehydration condensation reaction, and the reaction solution was cooled to 85°C. 360.0 g of water was added and stirred at 75-85°C, and the aqueous layer was separated and removed three times. The resulting organic layer was concentrated in a rotary evaporator to a solution of approximately 50% by mass. This solution was poured into 4678 g of IPA, and the precipitated solid was collected and vacuum-dried at 60°C to obtain citraconimide (CI1) represented by the following formula.

[0061] <Synthesis Example 4> In a 500 mL reactor equipped with a condenser, a Dean-Stark apparatus, and a stirrer, 17.9 g of citraconic anhydride and 47.7 g of toluene were added and mixed. A solution of 25.0 g of 1,3-bis[2-(4-aminophenyl)-2-propyl]benzene dissolved in 100.0 g of toluene and 12.0 g of NMP was added dropwise and the mixture was allowed to react for 30 minutes. After adding 1.4 g of p-toluenesulfonic acid monohydrate to the reaction mixture, the reaction was heated and the water produced by the dehydration condensation reaction was removed from the system by distillation while the reaction was continued at 105-110°C for 3 hours, and the reaction mixture was cooled to 100°C. 75.0 g of water was added to this mixture, and the mixture was stirred at 75-85°C. After allowing it to stand and separating and removing the aqueous layer, this process was repeated three times. The resulting organic layer was then concentrated using a rotary evaporator to obtain a toluene solution (CI2) containing biscitraconimide, represented by the following formula, at a concentration of 35.5% by mass.

[0062] <Synthesis Example 5> In a 500 mL reactor equipped with a condenser, a Dean-Stark apparatus, and a stirrer, 20.0 g of 4,4'-diamino-2,2'-dimethylbiphenyl, 142.1 g of toluene, and 7.8 g of NMP were added and mixed. 23.2 g of anhydrous citraconic acid was added dropwise, and the mixture was reacted for 30 minutes. 1.8 g of p-toluenesulfonic acid monohydrate was added to the reaction mixture, and the reaction was continued at 105-110°C for 4 hours while the water produced by the dehydration condensation reaction was removed from the system by distillation. 54.3 g of NMP was added to the reaction mixture, and the reaction was continued for another hour, after which the reaction mixture was cooled to 100°C. 60.0 g of water was added, and the mixture was stirred at 75-85°C. The aqueous layer was separated and removed three times, and the resulting organic layer was concentrated in a rotary evaporator to a solution of approximately 40%. This solution was poured into 754 g of IPA, and the precipitated solid was collected and vacuum-dried at 60°C to obtain biscitraconimide (CI3) represented by the following formula.

[0063] <Comparative Synthesis Example 1> In a 500 mL reactor equipped with a condenser, a Dean-Stark apparatus, and a stirrer, 15.7 g of maleic anhydride and 62.8 g of toluene were added and mixed. A solution of 25.0 g of 1,3-bis[2-(4-aminophenyl)-2-propyl]benzene dissolved in 100.0 g of toluene and 7.0 g of NMP was added dropwise and the mixture was reacted for 30 minutes. After adding 1.4 g of p-toluenesulfonic acid monohydrate to this reaction solution, the reaction solution was heated and the reaction was continued at 105-110°C for 4 hours while distilling off the water produced by the dehydration condensation reaction, and the reaction solution was cooled to 100°C. 75.0 g of water was added and stirred at 75-85°C, and the aqueous layer was separated and removed three times. The resulting organic layer was concentrated in a rotary evaporator to a solution of approximately 50%. This solution was poured into 366 g of IPA, and the precipitated solid was collected and vacuum-dried at 60°C to obtain bismaleimide (MI2) represented by the following formula.

[0064] <Comparative Synthesis Example 2> In a 500 mL reactor equipped with a condenser, a Dean-Stark apparatus, and a stirrer, 20.3 g of maleic anhydride and 140.9 g of toluene were added and mixed. A solution of 20.0 g of 4,4'-diamino-2,2'-dimethylbiphenyl dissolved in 60.0 g of NMP was added dropwise and the mixture was reacted for 30 minutes. After adding 1.8 g of p-toluenesulfonic acid monohydrate to this reaction solution, the reaction solution was heated and the reaction was continued at 105-110°C for 4 hours while distilling off the water produced by the dehydration condensation reaction, and the reaction solution was cooled to 100°C. 60.0 g of water was added and stirred at 75-85°C, and the aqueous layer was separated and removed three times. The resulting organic layer was concentrated in a rotary evaporator to a solution of approximately 60%. This solution was poured into 702 g of IPA, and the precipitated solid was collected and vacuum-dried at 60°C to obtain bismaleimide (MI3) represented by the following formula.

[0065] <Comparative Synthesis Example 3> 79.3 g of 4,4'-diaminodiphenylmethane, 75.3 g of phenol, and 206.8 g of toluene were added to a 500 mL reactor equipped with a condenser, a Dean-Stark apparatus, and a stirrer, and dissolved at 75°C. Next, 52.2 g of 92% by mass of paraformaldehyde was added in five portions. The reaction solution was heated to 105°C over approximately 3 hours, and after the water produced by the dehydration condensation reaction was removed from the system, the reaction solution was cooled to room temperature. This reaction solution was poured into 1034 g of IPA, the precipitated solid was collected, and the reaction product (BZO3) was obtained by vacuum drying at 50°C. The obtained reaction product was a benzoxazine containing the compound represented by the following formula as the main product, and the purity of the main product by GPC analysis was 44.1%.

[0066] <Comparative Synthesis Example 4> In a 300 mL reactor equipped with a condenser, a Dean-Stark apparatus, and a stirrer, 21.2 g of 4,4'-diamino-2,2'-dimethylbiphenyl, 18.8 g of phenol, and 53.0 g of toluene were added and dissolved at 75°C. Next, 13.0 g of 92% by mass of paraformaldehyde was added in five portions, and the reaction mixture was heated to remove the water produced by the dehydration condensation reaction. The reaction mixture was further heated to 105-110°C and the reaction was continued for 4 hours, after which the reaction mixture was cooled to room temperature. This reaction mixture was poured into 530 g of methanol, the precipitated solid was collected, and the reaction product (BZO4) was obtained by vacuum drying at 40°C. The obtained reaction product was a benzoxazine containing the compound represented by the following formula as the main product, and the purity of the main product by GPC analysis was 45.1%.

[0067] <Examples 1-6 and Comparative Examples 1-5> Resin compositions for Examples 1-6 and Comparative Examples 1-5 were prepared according to the formulations (parts by mass) shown in Table 1 below, and their solubility, moldability, glass transition temperature (Tg), and water absorption rate were evaluated or measured. In the table, "BZO / CI" refers to the mass ratio of benzoxazine (BZO) to biscitraconimide (CI), except for Comparative Examples 2-4, where it refers to the mass ratio of benzoxazine (BZO) to maleimide (MI).

[0068]

[0069] As shown in Table 1, the resin compositions of Examples 1 to 6, which used allyl group-containing benzoxazine BZO1 in combination with biscitraconimide, showed a significantly improved glass transition temperature of the cured product compared to the resin composition of Comparative Example 1, which used allyl group-containing benzoxazine BZO1 alone. Furthermore, while Comparative Examples 2 to 4, which used bismaleimide, a similar substance, instead of biscitraconimide, exhibited poor solvent solubility, Examples 1 to 6, which used biscitraconimide in combination, showed better solvent solubility and superior moldability compared to Comparative Examples 2 to 4. In addition, Comparative Example 5, which used benzoxazine BZO3 without an allyl group, had a higher water absorption rate in the cured product compared to Examples 1 to 6, and was inferior in terms of low water absorption.

[0070] <Examples 7-11 and Comparative Examples 6-11> Resin compositions for Examples 7-11 and Comparative Examples 6-11 were prepared according to the formulations (parts by mass) shown in Table 2 below, and their solubility, moldability, glass transition temperature (Tg), and water absorption rate were evaluated or measured. In the table, "BZO / CI" refers to the mass ratio of benzoxazine (BZO) to biscitraconimide (CI), except for Comparative Examples 7-8, where it refers to the mass ratio of benzoxazine (BZO) to maleimide (MI).

[0071]

[0072] As shown in Table 2, the resin compositions of Examples 7 to 11, which used allyl group-containing benzoxazine BZO2 in combination with biscitraconimide, showed a significantly improved glass transition temperature of the cured product compared to the resin composition of Comparative Example 6, which used allyl group-containing benzoxazine BZO2 alone. Furthermore, while Comparative Examples 7 and 8, which used bismaleimide, a similar substance, instead of biscitraconimide, exhibited poor solvent solubility, Examples 7 to 11, which used biscitraconimide in combination, showed better solvent solubility and superior moldability compared to Comparative Examples 7 and 8. In addition, the resin compositions of Comparative Examples 9 to 11, which used other allyl group-containing compounds (allyl 1, 2) or benzoxazine BZO4 without an allyl group instead of allyl group-containing benzoxazine, showed poor moldability, and satisfactory cured plates could not be obtained, making it impossible to obtain test pieces for measuring the glass transition temperature.

[0073] Furthermore, the various numerical ranges described in this specification can be any combination of their upper and lower limits, and all such combinations are described herein as preferred numerical ranges. Also, the description of a numerical range as "X to Y" means X or greater and Y or less.

[0074] Although several embodiments of the present invention have been described above, these embodiments are presented as examples and are not intended to limit the scope of the invention. These embodiments can be implemented in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their omissions, substitutions, and modifications are included in the scope and spirit of the invention, as well as in the claims and their equivalents.

[0075] The resin composition according to this embodiment can be used, for example, in printed circuit board materials, semiconductor encapsulating resins, matrix resins for composite materials, paints, adhesives, and the like.

Claims

1. A compound comprising the compound represented by the following general formula (1) and the compound represented by the following general formula (2), In formula (1), R １ R represents a divalent hydrocarbon group having 1 to 100 carbon atoms, which may contain heteroatoms. ２ and R ３ Each of these independently represents an alkanediyl group having 1 to 10 carbon atoms, R ４ and R ５ Each of these independently represents a hydrogen atom or a methyl group, R ６ and R ７ Each of these independently represents either a methyl group or an ethyl group, and each of p and q independently represents an integer between 0 and 2. In formula (2), R ８ A resin composition in which represents a divalent hydrocarbon group having 1 to 100 carbon atoms, which may contain heteroatoms.

2. R in the formula (1) １ The resin composition according to claim 1, wherein is a divalent aromatic ring-containing hydrocarbon group having 6 to 50 carbon atoms which may contain a hetero atom.

3. The compound represented by formula (1) above is represented by the following general formula (1A), In formula (1A), R １１ This is a single bond, -CH ２ -, -CH(CH ３ )-,-C(CH ３ ) ２ - or -O- represents R １２ and R １３ Each independently represents a methyl group or an ethyl group, and s and t each independently represent an integer from 0 to 4, R ２ and R ３ Each of these independently represents an alkanediyl group having 1 to 10 carbon atoms, R ４ and R ５ Each of these independently represents a hydrogen atom or a methyl group, R ６ and R ７ The resin composition according to claim 1, wherein each of the following independently represents a methyl group or an ethyl group, and p and q each independently represent an integer from 0 to 2.

4. R in formula (2) above ８ The resin composition according to claim 1, wherein is a divalent aromatic ring-containing hydrocarbon group having 6 to 50 carbon atoms, which may contain heteroatoms.

5. The compound represented by formula (2) above is represented by the following general formula (2A), In formula (2A), R ２１ This is a single bond, -CH ２ -, -CH(CH ３ )-,-C(CH ３ ) ２ -, -O-, or a group represented by the following formula (21A), R ２２ and R ２３ Each independently represents a methyl group or an ethyl group, and each independently represents an integer from 0 to 4. In formula (21A), R ２４ and R ２５ Each is independently -CH ２ -, -CH(CH ３ )-,-C(CH ３ ) ２ The resin composition according to claim 1, which represents - or -O-.

6. A resin composition according to any one of claims 1 to 5, which is used as a printed circuit board material.

7. A cured product obtained by curing the resin composition according to any one of claims 1 to 5.

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