CN116003960A

CN116003960A - Resin composition, and adhesive film and printed circuit board comprising resin composition

Info

Publication number: CN116003960A
Application number: CN202211622409.8A
Authority: CN
Inventors: 汪青; 刘东亮; 刘潜发
Original assignee: Shengyi Technology Co Ltd
Current assignee: Shengyi Technology Co Ltd
Priority date: 2022-12-16
Filing date: 2022-12-16
Publication date: 2023-04-25

Abstract

The invention provides a resin composition, and a glue film and a printed circuit board comprising the same, wherein the resin composition comprises the following components in parts by weight: 40-70 parts of resin, 30-60 parts of filler and 1-10 parts of core-shell copolymer toughening agent. In the invention, the core-shell copolymer toughening agent can enable the adhesive film and the resin-coated copper foil prepared from the resin composition to have high-temperature elongation and copper foil peeling strength, have lower CTE, can well solve the problem that the elongation is negatively influenced due to the addition of high-filling inorganic filler, and can be applied to the printed circuit board of a multi-layer laminate, in particular to the printed circuit board of the multi-layer laminate for manufacturing fine lines.

Description

Resin composition, and adhesive film and printed circuit board comprising resin composition

Technical Field

The invention belongs to the technical field of resin adhesive films, and relates to a resin composition, an adhesive film containing the resin composition and a printed circuit board.

Background

Along with the trend of the electronic information products mainly oriented to the light, thin, short and small multifunctional design in the future, the printed circuit board serving as the main support of the electronic components is also continuously improved in technical aspects so as to provide high-density wiring, thinness, micro-aperture, multidimensional three-dimensional and the like. The substrate material largely determines the performance of the printed circuit substrate, and thus, development of a new generation of base material is urgently required.

The adhesive film or resin-coated copper foil without reinforcing material is developed and used as a new generation of base material because it can realize thinner shape, high density wiring, fine aperture, multidimensional three-dimensional molding, etc. Since there is no reinforcing material, a highly filled inorganic filler is generally added to improve the thermal expansion coefficient, chemical resistance, mechanical strength, processability, etc. of the adhesive film material. However, the elongation of the adhesive film is negatively affected due to the introduction of the high-filling inorganic filler, and in order to compensate the elongation, a toughening agent such as rubber can be added for toughening, however, the newly introduced toughening agent can deteriorate other performances. How to improve the elongation of the adhesive film without degrading other properties, especially CTE, is the focus of research.

Accordingly, there is a need in the art for a fine line material that can improve the elongation after high temperature of the adhesive film and the peel strength of the copper foil, while maintaining low CTE performance.

Disclosure of Invention

In view of the shortcomings of the prior art, the invention aims to provide a resin composition, and a glue film and a printed circuit board comprising the resin composition.

To achieve the purpose, the invention adopts the following technical scheme:

in one aspect, the present invention provides a resin composition comprising the following components in parts by weight:

30-70 parts of resin

30-60 parts of filler

1-10 parts of core-shell copolymer toughening agent,

the core-shell copolymer comprises a core of polymer and at least two shells of polymer, each of the at least two shells comprising a different polymer and at least one of the shells comprising a gradient polymer.

In the invention, the core-shell copolymer toughening agent is selected to ensure that the adhesive film and the resin-coated copper foil prepared from the resin composition have high-temperature elongation and copper foil peeling strength, have lower CTE, can well solve the problem that the elongation is negatively influenced due to the addition of high-filling inorganic filler, and can be applied to the printed circuit board of a multi-layer laminate, in particular to the printed circuit board of a multi-layer laminate for manufacturing fine lines.

The gradient polymer is a copolymer composed of at least two different monomers (a) and (B) and having a gradient in repeating units arranged along the copolymer from a majority of the monomers (a) to a majority of the monomers (B). Such core-shell copolymers may be prepared by emulsion polymerization, for example, a suitable method is a two-stage polymerization technique in which the core and shell are produced in two sequential emulsion polymerization stages. If more shells are present, then an additional emulsion polymerization stage occurs. In the polymerization stage reaction, the first monomer of styrene is incorporated mainly during the initial stage of polymerization while the amount of the second monomer of methyl methacrylate is increased until the methyl methacrylate is incorporated mainly or completely during the final stage of polymerization, thereby forming a gradient zone. See CN102603989a and CN102585101a for more details regarding the method of making such core-shell copolymers. Such core-shell copolymers are also commercially available, for example, arkema describes CLEARSTRENGTH XT, dow chemical, PARALOID EXL-2650J as a methyl methacrylate-butadiene-styrene core-shell copolymer toughening agent which is good in compatibility and dispersibility in resin compositions.

Preferably, the core of the core-shell copolymer toughening agent comprises polybutadiene, the middle shell comprises a gradient polymer of styrene, and the outer shell comprises methyl methacrylate.

In the present invention, the content of the resin in the resin composition is 30 parts, 35 parts, 40 parts, 45 parts, 48 parts, 50 parts, 55 parts, 58 parts, 60 parts, 65 parts, 68 parts or 70 parts.

In the present invention, the content of the filler in the resin composition is 30 parts, 35 parts, 38 parts, 40 parts, 45 parts, 48 parts, 50 parts, 55 parts, 58 parts or 60 parts.

In the invention, the content of the core-shell copolymer toughening agent is 1 part, 2 parts, 3 parts, 5 parts, 7 parts, 9 parts or 10 parts.

In the present invention, the "parts" and "parts by weight" are calculated as the solid content, and do not include a solvent, a dispersant, and the like.

Preferably, the resin is any one or a combination of at least two of epoxy resin, phenol-oxygen resin, cyanate ester, polyphenyl ether, maleimide resin, hydrocarbon resin, acrylate resin, polyimide resin, organic silicon resin, polyester resin or polystyrene.

Preferably, the epoxy resin comprises any one or a combination of at least two of bisphenol a type epoxy resin, bisphenol F type epoxy resin, phosphorous containing epoxy resin, MDI modified epoxy resin, phenolic epoxy resin, biphenyl type epoxy resin, dicyclopentadiene type epoxy resin, naphthalene containing epoxy resin, or cycloaliphatic epoxy resin.

Preferably, the filler is an inorganic filler.

Preferably, the filler is a silica-based filler, preferably spherical silica.

Preferably, the resin composition further comprises a curing agent comprising any one or a combination of two of a phenolic resin or an active ester.

Preferably, the phenolic resin comprises any one or a combination of at least two of bisphenol a type phenolic resin, phenol type phenolic resin, biphenyl type phenolic resin, dicyclopentadiene type phenolic resin or naphthol containing phenolic resin.

In the present invention, when the main resin contains epoxy resin, the curing agent may be phenolic resin, active ester or cyanate ester, and thiol or amine (such as dicyandiamide or aromatic amine) curing agent is not suitable, which causes the problem of increase of CTE of the adhesive film.

Preferably, the content of the curing agent in the resin composition is 10 to 30 parts. For example, 10 parts, 15 parts, 18 parts, 20 parts, 25 parts, 28 parts or 30 parts.

In the present invention, a thermoplastic resin such as a polyvinyl acetal resin, a polyamideimide resin, a polyether sulfone resin, a polysulfone resin, and the like may be further added without affecting the overall performance of the resin composition.

In another aspect, the present invention provides a resin dope obtained by dissolving or dispersing the resin composition as described above in a solvent.

The solvent in the present invention is not particularly limited, and specific examples thereof include alcohols such as methanol, ethanol and butanol, ethers such as ethyl cellosolve, butyl cellosolve, ethylene glycol-methyl ether, carbitol and butyl carbitol, ketones such as acetone, butanone, methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone, aromatic hydrocarbons such as toluene, xylene and mesitylene, esters such as ethoxyethyl acetate and ethyl acetate, and nitrogen-containing solvents such as N, N-dimethylformamide, N-dimethylacetamide and N-methyl-2-pyrrolidone. The above solvents may be used singly or in combination of two or more, and are preferably used by mixing an aromatic hydrocarbon solvent such as toluene, xylene, mesitylene, etc. with a ketone flux such as acetone, butanone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, etc. The amount of the solvent to be used may be selected by one skilled in the art according to his own experience, so that the resulting resin dope may have a viscosity suitable for use.

In another aspect, the present invention provides an adhesive film comprising a release film, and the resin composition as described above attached to the release film after drying by coating, and a protective film coated on the resin composition.

The adhesive film provided by the invention has the advantages that the adhesive film has higher high-temperature elongation and copper foil peeling strength and has lower CTE due to the resin composition.

Preferably, the thickness of the adhesive film is 5-300 μm, for example 5 μm, 8 μm, 10 μm, 20 μm, 30 μm, 50 μm, 80 μm, 100 μm, 150 μm, 180 μm, 200 μm, 230 μm, 250 μm, 280 μm or 300 μm, preferably 10-200 μm, further preferably 20-100 μm.

Preferably, the film has an elongation of 10-20%, e.g. 10%, 12%, 15%, 18% or 20%, at 150 ℃ after curing.

Preferably, the peel strength of the cured copper plated copper foil of the adhesive film is > 6.0N/cm, such as 6.2N/cm, 6.5N/cm, 6.8N/cm, 7.0N/cm, 7.2N/cm, 7.5N/cm, 7.8N/cm, or 8.0N/cm, etc.

In another aspect, the present invention provides a resin-coated copper foil comprising a copper foil, a resin layer and a protective film coated on the resin layer, wherein the resin layer is a resin composition as described above attached to the copper foil after drying by coating.

Preferably, the thickness of the resin layer is 5 to 300 μm, for example, 5 μm, 8 μm, 10 μm, 20 μm, 30 μm, 50 μm, 80 μm, 100 μm, 150 μm, 180 μm, 200 μm, 230 μm, 250 μm, 280 μm or 300 μm, preferably 10 to 200 μm, further preferably 20 to 100 μm.

Preferably, the copper foil has a thickness of 1 to 105 μm, for example 1 μm, 3 μm, 5 μm, 8 μm, 10 μm, 20 μm, 30 μm, 50 μm, 80 μm, 100 μm or 105 μm, preferably 3 to 35 μm, further preferably 5 to 18 μm.

In another aspect, the present invention provides a prepreg comprising a substrate and the resin composition as described above attached to the substrate after impregnation drying.

The prepregs of this invention may also be referred to as prepregs or bonding sheets, and the substrates of this invention may also be referred to as reinforcing materials.

Preferably, the substrate is E-glass fiber cloth, NE-glass fiber cloth, quartz glass fiber cloth, aromatic amine cloth or the like.

In another aspect, the present invention provides a laminate comprising at least one prepreg as described above.

In another aspect, the present invention provides a metal foil-clad laminate comprising one or at least two laminated prepregs as described above, and a metal foil on one or both sides of the laminated prepregs.

Preferably, the metal foil is copper foil.

In another aspect, the present invention provides a printed circuit board comprising one or at least two superimposed prepregs as described above.

Compared with the prior art, the invention has the following beneficial effects:

Detailed Description

The technical scheme of the invention is further described by the following specific embodiments. It will be apparent to those skilled in the art that the examples are merely to aid in understanding the invention and are not to be construed as a specific limitation thereof.

Example 1

40 parts of epoxy resin (HEXION, EPR 627) and 19 parts of phenolic resin (Dow chemical, XZ 92741), 40 parts of silica (admatechs, 2050 MB), 1 part of core-shell copolymer toughening agent (ARKEMA, XT 100) were added to a butanone solvent and stirred for 2 hours to form a solution having a solids content of 65%.

And coating the solution on a release film, airing, and then placing the release film in a baking oven at 120 ℃ for baking for 5 minutes to obtain the adhesive film of the semi-cured resin layer. And (3) pressing and curing the semi-cured adhesive film (with the thickness of 40 mu m) and the browned PCB (the temperature is 100 ℃, the pressure is 0.5MPa, the time is 1 min), tearing off the release film, and then carrying out surface treatment and copper melting electroplating to form the laminated printed circuit board with the circuit.

Example 2

37 parts of epoxy resin (Japanese chemical, NC 3000H) and 18 parts of phenolic resin (HEXION, PHL 6635), 40 parts of silica (admatechs, 2050 MB), 5 parts of core-shell copolymer toughening agent (ARKEMA, XT 100) were added to a butanone solvent and stirred for 2 hours to form a solution having a solid content of 65%.

Example 3

34 parts of epoxy resin (Michigan, EPIKOTE 1001) and 16 parts of active ester (DIC, HPC-8000-65T, japan), 40 parts of silica (admatechs, 2050 MB), 10 parts of core-shell copolymer toughening agent (ARKEMA, XT 100) were added to a butanone solvent and stirred for 2 hours to form a solution having a solid content of 65%.

Example 4

25 parts of cyanate ester (Longsha, BA 3000) and 30 parts of maleimide resin (CYTEC, M5250), 40 parts of silica (admatechs, 2050 MB), 5 parts of core-shell copolymer toughening agent (ARKEMA, XT 100) were added to a butanone solvent and stirred for 2 hours to form a solution having a solids content of 65%.

Example 5

30 parts of polyphenylene ether (SABIC, MX 90) and 25 parts of hydrocarbon resin (Japanese Cao da, B3000), 40 parts of silica (admatechs, 2050 MB), 5 parts of a core-shell copolymer toughening agent (Dow chemical, EXL-2650J) were added to a butanone solvent and stirred for 2 hours to form a solution having a solid content of 65%.

Example 6

The difference from example 2 was only that the phenolic resin (hexin, PHL 6635) in example 2 was replaced with an equivalent weight part of an amine curing agent (basf, dicyandiamide).

Comparative example 1

40 parts of epoxy resin (HEXION, EPR 627) and 20 parts of phenolic resin (Dow chemical, XZ 92741) and 40 parts of silica (admatechs, 2050 MB) were added to a butanone solvent and stirred for 2 hours to form a solution having a solid content of 65%.

Comparative example 2

39.5 parts of epoxy resin (HEXION, EPR 627) and 20 parts of phenolic resin (Dow chemical, XZ 92741), 40 parts of silica (admatechs, 2050 MB), 0.5 parts of core-shell copolymer toughening agent (ARKEMA, XT 100), and the mixture was added to a butanone solvent and stirred for 2 hours to form a solution having a solid content of 65%.

Comparative example 3

33 parts of an epoxy resin (Michigan, EPIKOTE 1001) and 15 parts of a phenolic resin (Japanese Ming Hei, 7851H), 40 parts of silica (admatechs, 2050 MB), 12 parts of a core-shell copolymer toughening agent (ARKEMA, XT 100) were added to a butanone solvent and stirred for 2 hours to form a solution having a solid content of 65%.

Comparative example 4

The only difference from example 2 was that the core-shell copolymer toughening agent (ARKEMA, XT 100) in example 2 was replaced with an equal weight part of nitrile rubber (ZEON, nipol 1072 CG).

Comparative example 5

The only difference from example 2 was that the core-shell copolymer toughener (ARKEMA, XT 100) in example 2 was replaced with equal parts by weight of toughener AC-3816 (Ai Ke, inc.).

Comparative example 6

The only difference from example 2 is that the core-shell copolymer toughener (ARKEMA, XT 100) in example 2 was replaced with an equal weight part of toughener M732 (brillouin chemistry).

The performance test was performed on the examples and comparative examples as follows:

(1) Elongation percentage: adopting a DMA method, keeping the temperature at 150 ℃ for 5min, and pre-stressing to 0.01N,3N/min to 17.5N/min;

(2) Copper foil peel strength: testing by IPC-TM-650.2.4.9 method, and testing the peeling strength of the copper foil layer plated with the surface copper;

(3) Fine line capability: the percentage of short circuit does not appear in the test circuit after reflow soldering, when the percentage is more than 90 percent, the percentage is more than 80 percent, the percentage is less than 80 percent, and the rest percentage is good;

(4) CTE: the IPC-TM-650.2.4.24.5 method is adopted for testing;

(5) Tg (DSC): the test was performed using the IPC-TM-650.2.4.25 method.

The performance tests of the above examples and comparative examples are compared with the following tables 1 and 2.

TABLE 1

TABLE 2

As can be seen from tables 1 and 2, the adhesive films of examples 1 to 5 have high elongation and peel strength of copper foil, lower CTE and excellent fine wiring reliability. In example 6, the amine curing agent is adopted to cure the epoxy, so that the CTE of the adhesive film is obviously increased, and the performance requirement is difficult to meet.

Comparative example 1, without the addition of the core-shell copolymer toughening agent of the invention, the adhesive film has lower elongation and lower peel strength of the copper foil; the amount of the core-shell copolymer toughening agent added in the comparative example 2 is too small, the elongation is not improved, and the peel strength of the copper foil is low; comparative example 3 the amount of the core-shell copolymer toughening agent added was excessive, resulting in a large CTE of the adhesive film and poor performance. Comparative example 4 incorporated nitrile rubber as a toughening agent, resulting in an increase in CTE, a decrease in Tg, and poor performance of the adhesive film. Comparative examples 5 and 6, which incorporate other core-shell tougheners, do not have the same toughening effect as the core-shell copolymer tougheners of the present application, and the CTE performance of the adhesive film is relatively poor.

The applicant states that the present invention is illustrated by the above examples as well as the resin composition and the adhesive film and the printed circuit board comprising the same, but the present invention is not limited to the above examples, i.e., it does not mean that the present invention must be practiced depending on the above examples. It should be apparent to those skilled in the art that any modification of the present invention, equivalent substitution of raw materials for the product of the present invention, addition of auxiliary components, selection of specific modes, etc., falls within the scope of the present invention and the scope of disclosure.

Claims

1. A resin composition, characterized in that the resin composition comprises the following components in parts by weight:

30-70 parts of resin

30-60 parts of filler

1-10 parts of core-shell copolymer toughening agent,

2. The resin composition according to claim 1, wherein the resin is any one or a combination of at least two of epoxy resin, phenol resin, cyanate ester, polyphenylene ether, maleimide resin, hydrocarbon resin, acrylate resin, polyimide resin, silicone resin, polyester resin, or polystyrene;

preferably, the epoxy resin comprises any one or a combination of at least two of bisphenol a type epoxy resin, bisphenol F type epoxy resin, phosphorous containing epoxy resin, MDI modified epoxy resin, phenolic epoxy resin, biphenyl type epoxy resin, dicyclopentadiene type epoxy resin, naphthalene containing epoxy resin or alicyclic epoxy resin;

preferably, the filler is an inorganic filler;

preferably, the filler is a silica-based filler, preferably spherical silica.

3. The resin composition of claim 1 or 2, further comprising a curing agent comprising either one or a combination of both of a phenolic resin or an active ester;

preferably, the phenolic resin comprises any one or a combination of at least two of bisphenol A type phenolic resin, phenol type phenolic resin, biphenyl type phenolic resin, dicyclopentadiene type phenolic resin or naphthol-containing aldehyde resin;

preferably, the content of the curing agent in the resin composition is 10 to 30 parts.

4. A resin emulsion obtained by dissolving or dispersing the resin composition according to any one of claims 1 to 3 in a solvent.

5. An adhesive film comprising a release film, the resin composition according to any one of claims 1 to 3 attached to the release film after drying by coating, and a protective film coated on the resin composition;

preferably, the thickness of the adhesive film is 5 to 300 μm, preferably 10 to 200 μm, further preferably 20 to 100 μm;

preferably, the elongation of the adhesive film after curing at 150 ℃ is 10-20%;

preferably, the peel strength of the cured copper-plated copper foil of the adhesive film is more than 6.0N/cm.

6. A resin-coated copper foil, characterized in that the resin-coated copper foil comprises a copper foil, a resin layer and a protective film coated on the resin layer, the resin layer being the resin composition according to any one of claims 1 to 3 attached to the copper foil after drying by coating;

preferably, the thickness of the resin layer is 5 to 300 μm, preferably 10 to 200 μm, further preferably 20 to 100 μm;

preferably, the copper foil has a thickness of 1-105 μm.

7. A prepreg comprising a substrate and the resin composition according to any one of claims 1 to 3 attached to the substrate after impregnation drying.

8. A laminate comprising at least one prepreg according to claim 7.

9. A metal foil-clad laminate comprising one or at least two laminated prepregs according to claim 7 and a metal foil on one or both sides of the laminated prepregs.

10. A printed circuit board comprising one or at least two superimposed prepregs according to claim 7.