Resin composition, prepreg, circuit board and printed circuit board

Abstract

The present invention relates to a resin composition, the preparation raw materials of the resin composition comprise a first resin, a pre-dispersion liquid and a first solvent, and the pre-dispersion liquid comprises a second resin, a black pigment, a dispersant and a second solvent, the pre-dispersion liquid at least meets the following conditions: (1) the mass ratio of the second resin to the black pigment is greater than or equal to 3: 1; (2) the viscosity of the pre-dispersion liquid at 25 DEG C is less than or equal to 500 mPa.S; and (3) the dispersing agent is selected from ammonium salt containing saturated long-chain alkyl, and the carbon chain length of the alkyl is 12-24. The invention also relates to a prepreg, a circuit substrate and a printed circuit board. The circuit substrate prepared from the resin composition and the printed circuit board prepared from the circuit substrate have excellent shading property, color consistency and insulativity.

Description

Technical Field

[0001] The present invention relates to the technical field of the electronics industry, and particularly to a resin composition, a prepreg, a circuit board, and a printed circuit board. Background Art

[0002] In some fields, printed circuit boards (PCBs) are required to have excellent light-shielding properties, color consistency, and insulation properties.

[0003] Currently, carbon black or aniline black and other black pigments are mostly used to solve the light-shielding rate problem of circuit boards. Although good light-shielding effects can be achieved, due to defects such as poor dispersibility and easy adsorption and agglomeration of carbon black or aniline black and other black pigments in the resin composition, the insulation properties of the circuit board become poor, and micro-shorts are likely to form between circuits during the PCB processing, and even short-circuit phenomena occur; in addition, the dyeing efficiencies of carbon black or aniline black and other black pigments on resins and fillers are inconsistent, resulting in color deviation problems of the circuit board and poor color consistency. Summary of the Invention

[0004] Based on this, in view of the above problems, it is necessary to provide a resin composition, a prepreg, a circuit board, and a printed circuit board. The circuit board made of the resin composition and the printed circuit board made of the circuit board both have excellent light-shielding properties, color consistency, and insulation properties.

[0005] A resin composition, the preparation raw materials of the resin composition include a first resin, a pre-dispersion liquid, and a first solvent. Among them, the pre-dispersion liquid includes a second resin, a black pigment, a dispersant, and a second solvent. The pre-dispersion liquid at least satisfies the following conditions:

[0006] (1) The mass ratio of the second resin to the black pigment is greater than or equal to 3:1;

[0007] (2) The viscosity of the pre-dispersion liquid at 25 °C ≤ 500 mPa·S;

[0008] (3) The dispersant is selected from ammonium salts containing saturated long-chain alkyls, where the carbon chain length of the alkyl is 12-24.

[0009] In one embodiment, the pre-dispersion liquid further satisfies at least one of the following conditions:

[0010] (1) The mass ratio of the dispersant to the black pigment is 1:2 - 1:4;

[0011] (2) The sum of the mass fractions of the second resin and the black pigment in the pre-dispersion liquid is 30% - 50%.

[0012] In one embodiment, the pre-dispersion also satisfies at least one of the following conditions:

[0013] (1) The second resin is selected from at least one of benzoxazine resin, epoxy resin, phenolic resin, cyanate resin, and olefin resin;

[0014] (2) The black pigment is selected from at least one of carbon black, aniline black, and titanium black;

[0015] (3) The particle size of the black pigment is 40 nm - 200 nm;

[0016] (4) The mass ratio of the second resin to the black pigment is 4:1 - 6:1;

[0017] (5) The viscosity of the pre-dispersion at 25 °C is ≤ 300 mPa·S;

[0018] (6) The dispersant is selected from ammonium salts containing two or more saturated long-chain alkyl groups, wherein the carbon chain length of the alkyl group is 16 - 20.

[0019] In one embodiment, the pre-dispersion also satisfies at least one of the following conditions:

[0020] (1) The second resin is selected from ODA-type benzoxazine resin;

[0021] (2) The black pigment is selected from at least one of carbon black and aniline black;

[0022] (3) The particle size of the black pigment is 40 nm - 100 nm;

[0023] (4) The dispersant is selected from at least one of dioctadecyl dimethyl ammonium chloride, octadecyl trimethyl ammonium bromide, and N,N,N-trimethyl-1-tetradecyl ammonium bromide;

[0024] (5) The viscosity of the pre-dispersion at 25 °C is ≤ 100 mPa·S.

[0025] In one embodiment, the first resin is selected from at least one of benzoxazine resin, epoxy resin, and phenolic resin.

[0026] In one embodiment, the first resin is selected from a combination of benzoxazine resin and epoxy resin.

[0027] In one embodiment, when the first resin is selected from a combination of benzoxazine resin and epoxy resin, it also satisfies at least one of the following conditions:

[0028] (1) The benzoxazine resin is selected from at least one of MDA type benzoxazine resin, ODA type benzoxazine resin or allyl modified benzoxazine resin;

[0029] (2) The epoxy resin is selected from at least one of biphenyl type epoxy resin, naphthol type epoxy resin, novolac epoxy resin or DCPD type epoxy resin;

[0030] (3) The mass ratio of the benzoxazine resin to the epoxy resin is 1:1 - 4:1.

[0031] In one embodiment, in the resin composition, based on 100 parts by weight of the first resin, the addition amount of the pre-dispersion liquid is 10 parts by weight - 20 parts by weight.

[0032] In one embodiment, the resin composition further includes black spherical silica.

[0033] In one embodiment, the black spherical silica further satisfies at least one of the following conditions:

[0034] (1) Based on 100 parts by weight of the first resin, the addition amount of the black spherical silica is 90 parts by weight - 150 parts by weight;

[0035] (2) The conductivity of the black spherical silica is less than 50 μS / cm;

[0036] (3) The carbon content in the black spherical silica is greater than 3%;

[0037] (4) The particle size D 100 of the black spherical silica is less than 2 μm.

[0038] A prepreg made of the resin composition.

[0039] A circuit board made of the prepreg.

[0040] A printed circuit board made of the circuit board.

[0041] In the present invention, first, a special dispersant is used to pre-disperse the black pigment, and the mass ratio of the second resin to the black pigment and the viscosity of the pre-dispersion liquid are controlled, so that the second resin can wrap on the surface of the black pigment, thereby enabling the black pigment to be uniformly and stably dispersed in the pre-dispersion liquid. Furthermore, when the resin composition is prepared using the pre-dispersion liquid, the black pigment can be uniformly and stably dispersed in the resin composition. Therefore, both the circuit board made of the resin composition of the present invention and the printed circuit board made of the circuit board of the present invention have excellent light-shielding property, color consistency and insulation property. Detailed Embodiments

[0042] For the convenience of understanding the present invention, the present invention will be described in more detail below. However, it should be understood that the present invention can be implemented in many different forms and is not limited to the embodiments or examples described herein. On the contrary, these embodiments or examples are provided to make the understanding of the disclosure of the present invention more thorough and comprehensive.

[0043] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which the present invention belongs. The terms used in the description of the present invention herein are only for the purpose of describing specific embodiments or examples and are not intended to limit the present invention. The optional range of the term "and / or" used herein includes any one of two or more related listed items, and also includes any and all combinations of the related listed items, and the any and all combinations include any two related listed items, any more related listed items, or all related listed items.

[0044] The resin composition provided by the present invention is mainly used for preparing circuit boards, such as copper clad laminates, etc. The raw materials for preparing the resin composition include a first resin, a pre-dispersion liquid, and a first solvent. Among them, the pre-dispersion liquid includes a second resin, a black pigment, a dispersant, and a second solvent. The pre-dispersion liquid satisfies at least the following conditions:

[0045] (1) The mass ratio of the second resin to the black pigment is greater than or equal to 3:1;

[0046] (2) The viscosity of the pre-dispersion liquid at 25 °C is ≤500 mPa·S;

[0047] (3) The dispersant is selected from ammonium salts containing saturated long-chain alkyl groups, wherein the carbon chain length of the alkyl group is 12-24.

[0048] In the present invention, a special dispersant is first used to pre-disperse the black pigment in the resin, and the mass ratio of the second resin to the black pigment is controlled to be greater than or equal to 3:1 and the viscosity of the pre-dispersion liquid is controlled to be ≤500 mPa·S, so that the second resin can wrap on the surface of the black pigment, so that the black pigment can be uniformly and stably dispersed in the pre-dispersion liquid, improving the light-shielding property and color consistency of the circuit board, and at the same time preventing the aggregation of the black pigment from affecting the insulation of the circuit board.

[0049] Further, the dispersant is preferably an ammonium salt containing two or more saturated long-chain alkyl groups, wherein the carbon chain length of the alkyl group is preferably 16-20, and / or, the mass ratio of the second resin to the black pigment is preferably 4:1-6:1, more preferably 4:1-5:1, and / or, the viscosity of the pre-dispersion liquid at 25°C is preferably ≤300 mPa·S, more preferably ≤100 mPa·S, which can enable the black pigment to be uniformly and stably dispersed in the pre-dispersion liquid, improve the light-shielding property and color consistency of the circuit board, and further improve the insulation property.

[0050] Optionally, the sum of the mass fractions of the second resin and the black pigment in the pre-dispersion liquid is 30%-50%, and / or, the mass ratio of the dispersant to the black pigment is 1:2-1:4. Thus, combining the mass ratio of the second resin to the black pigment in the pre-dispersion liquid and the viscosity of the pre-dispersion liquid is more conducive to the dispersion uniformity and stability of the black pigment in the pre-dispersion liquid, and further improves the light-shielding property, color consistency and insulation property of the circuit board.

[0051] Then, using the pre-dispersion liquid to prepare the resin composition can enable the black pigment to be uniformly and stably dispersed in the resin composition. Therefore, the circuit board made of the resin composition of the present invention and the printed circuit board made of the circuit board of the present invention both have excellent light-shielding property, color consistency and insulation property.

[0052] In the present invention, there is no special requirement for the selection of the first resin, and it can be selected according to needs. Optionally, the first resin is selected from at least one of benzoxazine resin, epoxy resin, and phenolic resin.

[0053] Among them, the benzoxazine resin is preferably selected from at least one of ODA-type benzoxazine resin, MDA-type benzoxazine resin, allyl-modified benzoxazine resin, and heteroaromatic ring-type benzoxazine resin, preferably ODA-type benzoxazine resin, which has a darker color and is beneficial to light-shielding property and color consistency; the epoxy resin is preferably selected from at least one of o-cresol novolac epoxy resin, phenol novolac epoxy resin, trifunctional phenol novolac epoxy resin, brominated epoxy resin, biphenyl-type epoxy resin, binaphthyl-type epoxy resin, and DCPD-type epoxy resin, preferably DCPD-type epoxy resin, which has a darker color and is beneficial to light-shielding property and color consistency; the phenolic resin is preferably selected from at least one of linear phenolic resin, linear o-cresol novolac resin, biphenyl aralkyl phenolic resin, dicyclopentadiene phenolic resin, and phosphorus-containing phenolic resin, preferably phosphorus-containing phenolic resin.

[0054] Preferably, the first resin is selected from the combination of benzoxazine resin and epoxy resin. This combined resin has a relatively dark color, which can further improve the light-shielding rate and at the same time can improve the consistency of color distribution. Among them, the benzoxazine resin is selected from at least one of ODA-type benzoxazine resin, MDA-type benzoxazine resin or allyl-modified benzoxazine resin; the epoxy resin is selected from at least one of biphenyl-type epoxy resin, naphthol-type epoxy resin, novolac epoxy resin or DCPD-type epoxy resin. When combining, it can be a combination of two resins, or a combination of three resins or more resins. For example, it can be a combination of ODA-type benzoxazine resin and DCPD-type epoxy resin, or a combination of MDA-type benzoxazine resin and DCPD-type epoxy resin, or a combination of ODA-type benzoxazine resin, MDA-type benzoxazine resin and DCPD-type epoxy resin, or a combination of ODA-type benzoxazine resin, biphenyl-type epoxy resin and DCPD-type epoxy resin, etc. In addition, this combination can also be used in combination with other resins. For example, this combination is used in combination with phenolic resin.

[0055] In this combination, there is no special requirement for the mass ratio of benzoxazine resin to epoxy resin, and it can be selected according to needs. Preferably, the mass ratio of benzoxazine resin to epoxy resin is 1:1 - 4:1.

[0056] In the present invention, there is also no special requirement for the selection of the second resin, and it can be selected according to needs. Optionally, the second resin is selected from at least one of benzoxazine resin, epoxy resin, phenolic resin, cyanate resin, olefin resin, and is further preferably ODA-type benzoxazine resin, which has a relatively dark color and is beneficial to light-shielding property and color consistency.

[0057] In the present invention, the black pigment is preferably selected from at least one of carbon black, aniline black, and titanium black, and is further preferably selected from at least one of carbon black and aniline black. The particle size of the black pigment is preferably 40nm - 200nm, and further preferably 40nm - 100nm, which can further improve the light-shielding rate and at the same time can improve the consistency of color distribution.

[0058] In the present invention, the dispersant is selected from at least one of dioctadecyl dimethyl ammonium chloride, octadecyl trimethyl ammonium bromide, and N,N,N-trimethyl-1-tetradecyl ammonium bromide.

[0059] In the present invention, both the first solvent and the second solvent are selected from organic solvents, and are further selected from at least one of acetone, butanone, cyclohexanone, propylene glycol methyl ether, propylene glycol methyl ether acetate, N-N dimethylformamide, toluene, and xylene, and are preferably butanone.

[0060] In the resin composition of the present invention, based on 100 parts by weight of the first resin, the addition amount of the pre-dispersion liquid is 10 parts by weight to 20 parts by weight.

[0061] Optionally, the resin composition of the present invention further includes black spherical silica.

[0062] It should be noted that the core of the black spherical silica is a mixture of carbon and silica, and the shell layer is silica. The black spherical silica is preferably prepared by a synthetic method, so that the carbon content inside the black spherical silica can be increased by controlling the temperature and oxygen content during the calcination process.

[0063] Preferably, the conductivity of the black spherical silica is less than 50 μS / cm, and / or the carbon content in the black spherical silica is greater than 3%, and / or the particle size D of the black spherical silica 100 is less than 2 μm, so as to further improve the light-shielding rate and color consistency while ensuring insulation.

[0064] Based on 100 parts by weight of the first resin, the addition amount of the black spherical silica is 90 parts by weight to 150 parts by weight. Thus, by using the black spherical silica in combination, the light-shielding rate can be further improved while improving insulation and color consistency.

[0065] It should be noted that in the resin composition of the present invention, fillers such as silica and titanium dioxide, curing agents, curing accelerators, coupling agents, etc. can be selectively added as needed.

[0066] The preparation method of the resin composition provided by the present invention includes: first, fully stirring the second resin and the dispersant in the second solvent, then adding a black pigment, shearing and dispersing with a high-speed shearer and grinding with a sand mill to obtain a pre-dispersion liquid, and then adding the first resin and the pre-dispersion liquid to the first solvent and fully stirring, and after mixing, performing high-speed shearing and sand milling with a sand mill to obtain the resin composition.

[0067] The present invention also provides a prepreg made of the resin composition. The prepreg is formed on a reinforcing material such as an electronic-grade glass fiber cloth with the resin composition and obtained after drying.

[0068] The present invention also provides a circuit board made of the prepreg. The circuit board includes an insulating layer and a conductive layer provided on at least one surface of the insulating layer. Among them, the insulating layer is formed by pressing one or at least two laminated prepregs.

[0069] Specifically, the conductive layer is preferably a copper foil, and the circuit board is a copper-clad laminate.

[0070] The present invention also provides a printed circuit board made of the circuit board.

[0071] Since the black pigment can be uniformly and stably dispersed in the resin composition of the present invention, the circuit substrate made of the resin composition of the present invention and the printed circuit board made of the circuit substrate of the present invention both have excellent light-shielding properties, color consistency and insulation properties.

[0072] Hereinafter, the resin composition, prepreg, circuit substrate and printed circuit board will be further described through the following specific examples.

[0073] Example 1

[0074] Take 30 parts by mass of ODA-type benzoxazine, 20 parts by mass of butanone solvent and 3 parts by mass of dioctadecyl dimethyl ammonium chloride, stir them thoroughly, add 10 parts by mass of carbon black with a particle size of 40 nm, use a high-speed shearing machine to shear and disperse for 1 hour, then add 37 parts by mass of butanone solvent, and use a sand mill to grind for 1 hour to obtain a pre-dispersion liquid, the viscosity of the pre-dispersion liquid is 36 mPa·S.

[0075] 100 parts by mass of butanone, 50 parts by mass of ODA-type benzoxazine resin, 50 parts by mass of DCPD-type epoxy resin, 20 parts by mass of the above-obtained pre-dispersion liquid, and 120 parts by mass of black spherical silica (purchased from Jinyi, wherein the conductivity is 40 μS / cm, the carbon content is 9%, and the particle size D is 200 μm). 100 The particles were mixed thoroughly and then sheared at a high speed for 1 hour, and then sand-milled for 2 hours to obtain a resin composition.

[0076] The semi-cured sheet was prepared by impregnating electronic grade glass fiber cloth E-glass cloth and baking it at 150°C for 3 minutes.

[0077] Take two semi-cured sheets, cover both sides with electrolytic copper foil, place them in a vacuum hot press and hot press them at 230°C for 100 minutes to obtain a copper clad laminate.

[0078] Example 2

[0079] Take 40 parts by mass of ODA type benzoxazine, 25 parts by mass of butanone solvent and 2.5 parts by mass of octadecyltrimethylammonium bromide, stir them thoroughly, add 10 parts by mass of aniline black with a particle size of 150 nm, use a high-speed shearing machine to shear and disperse for 1 hour, then add 22.5 parts by mass of butanone solvent, use a sand mill to grind for 1 hour to prepare a pre-dispersion liquid, and the viscosity of the pre-dispersion liquid is 83mPa·S.

[0080] 100 parts by mass of butanone, 60 parts by mass of MDA-type benzoxazine resin, 40 parts by mass of biphenyl-type epoxy resin, 15 parts by mass of the above-obtained pre-dispersion liquid, and 90 parts by mass of black spherical silica (purchased from Jinyi, wherein the conductivity is 30 μS / cm, the carbon content is 7%, and the particle size D is 2.5-3.0).100 (with a particle size of 1.2 μm), after thorough mixing, it is sheared at high speed for 1 h, and then ground by a sand mill for 2 h to obtain a resin composition.

[0081] The E-glass cloth of electronic grade glass fiber cloth is impregnated and baked at 150 °C for 3 min to obtain a prepreg.

[0082] Take 2 prepregs, cover both sides with electrolytic copper foil, and place them in a vacuum hot press for hot pressing at 230 °C for 100 min to obtain a copper clad laminate.

[0083] Example 3

[0084] Take 50 parts by mass of ODA-type benzoxazine, 25 parts by mass of methyl ethyl ketone solvent, and 3 parts by mass of N,N,N-trimethyl-1-tetradecylammonium bromide. After thorough stirring, add 10 parts by mass of carbon black with a particle size of 80 nm, shear and disperse it with a high-speed shear machine for 1 h, then add 50 parts by mass of methyl ethyl ketone solvent, and grind it with a sand mill for 1 h to obtain a pre-dispersion liquid, and the viscosity of the pre-dispersion liquid is 42 mPa·S.

[0085] Add 100 parts by mass of methyl ethyl ketone, 70 parts by mass of allyl-modified benzoxazine resin, 30 parts by mass of naphthol-type epoxy resin, 10 parts by mass of the above-obtained pre-dispersion liquid, and 150 parts by mass of black spherical silica (purchased from JinYi, where the conductivity is 18 μS / cm, the carbon content is 5%, and the particle size D 100 is 0.5 μm), after thorough mixing, it is sheared at high speed for 1 h, and then ground by a sand mill for 2 h to obtain a resin composition.

[0086] The E-glass cloth of electronic grade glass fiber cloth is impregnated and baked at 150 °C for 3 min to obtain a prepreg.

[0087] Take 2 prepregs, cover both sides with electrolytic copper foil, and place them in a vacuum hot press for hot pressing at 230 °C for 100 min to obtain a copper clad laminate.

[0088] Example 4

[0089] Take 30 parts by mass of MDA-type benzoxazine resin, 20 parts by mass of methyl ethyl ketone solvent, and 3 parts by mass of dioctadecyl dimethyl ammonium chloride. After thorough stirring, add 10 parts by mass of carbon black with a particle size of 80 nm, shear and disperse it with a high-speed shear machine for 1 h, then add 37 parts by mass of methyl ethyl ketone solvent, and grind it with a sand mill for 1 h to obtain a pre-dispersion liquid, and the viscosity of the pre-dispersion liquid is 37 mPa·S.

[0090] Add 100 parts by mass of methyl ethyl ketone, 45 parts by mass of MDA-type benzoxazine, 35 parts by mass of biphenyl-type epoxy resin, 20 parts by mass of phosphorus-containing phenolic resin, 20 parts by mass of the above-prepared pre-dispersion liquid, and 100 parts by mass of black spherical silicon (purchased from Jin Yi, with a conductivity of 40 μS / cm, a carbon content of 9%, and a particle size D 100 being 1.8 μm), mix well and then perform high-speed shearing for 1 h, and then grind with a sand mill for 2 h to obtain a resin composition.

[0091] Impregnate an E-glass cloth of electronic grade and bake at 150 °C for 3 min to obtain a prepreg.

[0092] Take 2 prepregs, cover both sides with electrolytic copper foil, and place them in a vacuum hot press to hot press at 230 °C for 100 min to obtain a copper-clad laminate.

[0093] Example 5

[0094] The difference between Example 5 and Example 1 is only that: take 30 parts by mass of OD-type benzoxazine, 15 parts by mass of methyl ethyl ketone solvent, and 3 parts by mass of dioctadecyl dimethyl ammonium chloride, stir well, add 10 parts by mass of carbon black with a particle size of 40 nm, use a high-speed shearer to shear and disperse for 1 h, then add 15 parts by mass of methyl ethyl ketone solvent, and use a sand mill to grind for 1 h to obtain a pre-dispersion liquid, and the viscosity of the pre-dispersion liquid is 285 mPa·S.

[0095] Example 6

[0096] The difference between Example 6 and Example 1 is only that: the particle size of the carbon black used in the pre-dispersion liquid is 300 nm, and the viscosity of the obtained pre-dispersion liquid is 40 mPa·S.

[0097] Example 7

[0098] The difference between Example 7 and Example 1 is only that: take 30 parts by mass of OD-type benzoxazine, 20 parts by mass of methyl ethyl ketone solvent, and 1 part by mass of dioctadecyl dimethyl ammonium chloride, stir well, add 10 parts by mass of carbon black with a particle size of 40 nm, use a high-speed shearer to shear and disperse for 1 h, then add 39 parts by mass of methyl ethyl ketone solvent, and use a sand mill to grind for 1 h to obtain a pre-dispersion liquid, and the viscosity of the pre-dispersion liquid is 256 mPa·S.

[0099] Example 8

[0100] The difference between Example 8 and Example 1 is only that: use lauryl trimethyl ammonium bromide to replace dioctadecyl dimethyl ammonium chloride, and the viscosity of the obtained pre-dispersion liquid is 115 mPa·S.

[0101] Example 9

[0102] Example 9 is different from Example 1 only in that: in Example 9, black spherical silica is not added.

[0103] Example 10

[0104] Example 10 is different from Example 1 only in that: in Example 10, silica (with a conductivity of 20 μS / cm and a particle size D 100 of 1.5 μm) is used instead of black spherical silica.

[0105] Comparative Example 1

[0106] Comparative Example 1 is different from Example 1 only in that: 30 parts by mass of MDA-type benzoxazine, 15 parts by mass of methyl ethyl ketone solvent, and 3 parts by mass of dioctadecyl dimethyl ammonium chloride are taken. After stirring well, 10 parts by mass of carbon black with a particle size of 40 nm is added, and it is sheared and dispersed for 1 h using a high-speed shear machine. Then, 10 parts by mass of methyl ethyl ketone solvent is added, and it is ground for 1 h using a sand mill to obtain a pre-dispersed liquid, and the viscosity of the pre-dispersed liquid is 849 mPa·S.

[0107] Comparative Example 2

[0108] Comparative Example 2 is different from Example 1 only in that: 20 parts by mass of MDA-type benzoxazine, 20 parts by mass of methyl ethyl ketone solvent, and 3 parts by mass of dioctadecyl dimethyl ammonium chloride are taken. After stirring well, 10 parts by mass of carbon black with a particle size of 40 nm is added, and it is sheared and dispersed for 1 h using a high-speed shear machine. Then, 22 parts by mass of methyl ethyl ketone solvent is added, and it is ground for 1 h using a sand mill to obtain a pre-dispersed liquid, and the viscosity of the pre-dispersed liquid is 40 mPa·S.

[0109] Comparative Example 3

[0110] Comparative Example 3 is different from Example 1 only in that: 30 parts by mass of MDA-type benzoxazine, 20 parts by mass of methyl ethyl ketone solvent, and 3 parts by mass of tetrabutyl ammonium perchlorate are taken. After stirring well, 10 parts by mass of carbon black with a particle size of 40 nm is added, and it is sheared and dispersed for 1 h using a high-speed shear machine. Then, 37 parts by mass of methyl ethyl ketone solvent is added, and it is ground for 1 h using a sand mill to obtain a pre-dispersed liquid, and the viscosity of the pre-dispersed liquid is 363 mPa·S.

[0111] Comparative Example 4

[0112] 100 parts by mass of methyl ethyl ketone, 50 parts by mass of MDA-type benzoxazine, 50 parts by mass of biphenyl-type epoxy resin, 10 parts by mass of carbon black with a particle size of 40 nm, and 100 parts by mass of black spherical silica (purchased from Jin Yi, where the conductivity is 40 μS / cm, the carbon content is 9%, and the particle size D 100 is 1.8 μm) are added to a container. After thorough mixing, it is sheared at high speed for 1 h, and then ground with a sand mill for 2 h to obtain a resin composition.

[0113] The semi-cured sheet was prepared by impregnating electronic grade glass fiber cloth E-glass cloth and baking it at 150°C for 3 minutes.

[0114] Take two semi-cured sheets, cover both sides with electrolytic copper foil, place them in a vacuum hot press and hot press them at 230°C for 120 minutes to obtain a copper clad laminate.

[0115] Comparative Example 5

[0116] 100 parts by mass of butanone, 50 parts by mass of MDA-type benzoxazine, 50 parts by mass of biphenyl-type epoxy resin, and 10 parts by mass of carbon black with a particle size of 40 nm were added to a container, and the mixture was fully mixed and sheared at high speed for 1 hour, and then sand-milled for 2 hours to obtain a resin composition.

[0117] The semi-cured sheet was prepared by impregnating electronic grade glass fiber cloth E-glass cloth and baking it at 150°C for 3 minutes.

[0118] Take two semi-cured sheets, cover both sides with electrolytic copper foil, place them in a vacuum hot press and hot press them at 230°C for 120 minutes to obtain a copper clad laminate.

[0119] The prepared copper clad laminate was tested using the following scheme, and the results are shown in Table 1.

[0120] Transmittance: Use Datacolor spectrometer to test transmittance, test wavelength 360-720nm, the sample is a bare board after etching and copper removal, and read the maximum transmittance at a wavelength of 360-720nm as the test result.

[0121] Color difference: Take a 150*150mm etched plate and use a Datacolor spectrometer to test the random 10-point Lab values. Calculate the variance of the 10-point Lab values, which is recorded as △L.

[0122] Dielectric strength: The test plan refers to IPC-TM-650 specification, unit KV / mm.

[0123] Table 1

[0124]

[0125]

[0126] By comparing the examples and comparative examples in Table 1, it can be seen that by first pre-dispersing the black pigment with a special dispersant and controlling the mass ratio of the second resin to the black pigment in the pre-dispersion liquid and the viscosity of the pre-dispersion liquid, the manufactured circuit substrate can have excellent light-shielding properties, color consistency and insulation properties, and can reach a level of transmittance ≤0.2%, color difference ≤1.5, and insulation strength ≥35KV / mm.

[0127] Meanwhile, by comparing Example 1 with Examples 4-8, it can be seen that optimizing each component in the pre-dispersion liquid can further enhance the excellent light-shielding property, color consistency, and insulation property of the fabricated circuit board. By comparing Example 1 with Examples 9-10, it can be seen that black silicon balls can further increase the light-shielding rate while improving the insulation property and color consistency.

[0128] By comparing Example 1 and Comparative Example 1 in Table 1, it can be seen that when the mass ratio of each component in the pre-dispersion liquid is changed such that the viscosity is greater than 500 mPa·S, the transmittance of the circuit board decreases, the color difference becomes larger, and the insulation strength decreases. At the same time, by comparing Example 1 and Comparative Example 2 in Table 1, it can be seen that when the mass ratio of the second resin to the black pigment in the pre-dispersion liquid is less than 3:1, even though the viscosity is still less than 500 mPa·S, the transmittance of the circuit board decreases, the color difference becomes larger, and the insulation strength decreases.

[0129] By comparing Example 1 and Comparative Example 3 in Table 1, it can be seen that when other dispersants are selected in the pre-dispersion liquid, although conditions such as viscosity can meet the requirements, the transmittance of the circuit board decreases, the color difference becomes larger, and the insulation strength decreases.

[0130] The technical features of the above-described embodiments can be combined arbitrarily. For the sake of brevity of description, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as within the scope described in this specification.

[0131] The above-described embodiments merely represent several implementation manners of the present invention. The description is relatively specific and detailed, but it should not be construed as a limitation on the scope of the invention patent. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several modifications and improvements can still be made, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the present invention patent should be subject to the appended claims.

Claims

1. A resin composition, characterized in that, The formulation raw materials of the resin composition include a first resin, a predispersion liquid, and a first solvent. Among them, the predispersion liquid includes a second resin, a black pigment, a dispersant, and a second solvent. The predispersion liquid satisfies at least the following conditions: (1) The mass ratio of the second resin to the black pigment is greater than or equal to 3:1; (2) The viscosity of the predispersion liquid at 25 °C is ≤500 mPa·S; (3) The dispersant is selected from ammonium salts containing saturated long-chain alkyl groups, where the carbon chain length of the alkyl group is 12 - 24.

2. The resin composition according to claim 1, wherein The predispersion liquid further satisfies at least one of the following conditions: (1) The mass ratio of the dispersant to the black pigment is 1:2 - 1:4; (2) The sum of the mass fractions of the second resin and the black pigment in the predispersion liquid is 30% - 50%.

3. The resin composition according to claim 2, wherein The predispersion liquid further satisfies at least one of the following conditions: (1) The second resin is selected from at least one of benzoxazine resin, epoxy resin, phenolic resin, cyanate resin, and olefin resin; (2) The black pigment is selected from at least one of carbon black, aniline black, and titanium black; (3) The particle size of the black pigment is 40 nm - 200 nm; (4) The mass ratio of the second resin to the black pigment is 4:1 - 6:1; (5) The viscosity of the predispersion liquid at 25 °C is ≤300 mPa·S; (6) The dispersant is selected from ammonium salts containing two or more saturated long-chain alkyl groups, where the carbon chain length of the alkyl group is 16 - 20.

4. The resin composition according to claim 3, wherein The predispersion liquid further satisfies at least one of the following conditions: (1) The second resin is selected from ODA-type benzoxazine resin; (2) The black pigment is selected from at least one of carbon black and aniline black; (3) The particle size of the black pigment is 40 nm - 100 nm; (4) The dispersant is selected from at least one of dioctadecyl dimethyl ammonium chloride, octadecyl trimethyl ammonium bromide, and N,N,N-trimethyl-1-tetradecyl ammonium bromide; (5) The viscosity of the predispersion liquid at 25 °C is ≤100 mPa·S.

5. The resin composition according to claim 1, characterized in that, The first resin is selected from at least one of benzoxazine resin, epoxy resin, and phenolic resin.

6. The resin composition according to claim 5, wherein The first resin is selected from a combination of benzoxazine resin and epoxy resin.

7. The resin composition according to claim 6, wherein When the first resin is selected from a combination of benzoxazine resin and epoxy resin, it further satisfies at least one of the following conditions: (1) The benzoxazine resin is selected from at least one of MDA-type benzoxazine resin, ODA-type benzoxazine resin, or allyl-modified benzoxazine resin; (2) The epoxy resin is selected from at least one of biphenyl-type epoxy resin, naphthol-type epoxy resin, phenolic epoxy resin, or DCPD-type epoxy resin; (3) The mass ratio of the benzoxazine resin to the epoxy resin is 1:1 - 4:

1.

8. The resin composition according to claim 1, wherein In the resin composition, based on 100 parts by weight of the first resin, the addition amount of the predispersion liquid is 10 parts by weight - 20 parts by weight.

9. The resin composition according to any one of claims 1 to 8, characterized in that, The resin composition further includes black spherical silica.

10. The resin composition according to claim 9, characterized in that, The black spherical silica further satisfies at least one of the following conditions: (1) Based on 100 parts by weight of the first resin, the addition amount of the black spherical silica is 90 parts by weight to 150 parts by weight; (2) The conductivity of the black spherical silica is less than 50 μS / cm; (3) The carbon content in the black spherical silica is greater than 3%; (4) The particle size D of the black spherical silicon 100 is less than 2 μm.

11. A prepreg made of the resin composition according to any one of claims 1-10.

12. A circuit board made of the prepreg according to claim 11.

13. A printed circuit board made of the circuit board according to claim 12.

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