Prepreg sheet, laminated board, and printed wiring board

Abstract

The invention discloses a prepreg sheet, a laminated board and a printed circuit board. The prepreg sheet is formed by impregnating a substrate in a resin composition. The resin composition comprises a furan modified resin, a thermosetting resin and a filler, and the furan modified resin is obtained through a reaction of a polymer resin and 2-furanmethylamine. The prepreg sheet, the laminated board and the printed circuit board disclosed by the invention have the characteristics of excellent electrical performance, high heat resistance, high dimensional stability and recoverability.

Description

Technical Field

[0001] The present invention relates to a prepreg, a laminate, and a printed circuit board, and particularly to a recyclable prepreg, a laminate, and a printed circuit board. Background Art

[0002] With the booming development of the information industry, electronic products are constantly updated, becoming one of the fastest-growing products in the global manufacturing industry. However, this also means that the life cycle of electronic and electrical equipment is shortened and the replacement rate increases, thus generating a large amount of waste of electrical and electronic equipment (WEEE).

[0003] Printed circuit boards are indispensable components in electronic and electrical equipment. If waste printed circuit boards are not properly treated, serious environmental problems are likely to occur. There are approximately 54.5% plastics in printed circuit boards, which mainly include insulating resins and glass fiber cloths. Since the resins used in printed circuit boards are all thermosetting resins and their properties are quite stable, it is also difficult to recycle them.

[0004] Therefore, how to improve the recovery rate of the resin system through the formulation improvement of the resin composition to improve the recycling of electronic equipment, promote the circular economy, and improve resource efficiency to overcome the above defects has become one of the important issues to be solved in this industry. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a prepreg, a laminate, and a printed circuit board in view of the deficiencies of the prior art.

[0006] To solve the above technical problem, one of the technical solutions adopted by the present invention is to provide a prepreg formed by impregnating a substrate with a resin composition, wherein the resin composition includes a furan-modified resin, a thermosetting resin, and a filler, and wherein the furan-modified resin is obtained by reacting a polymer resin with 2-furfurylamine.

[0007] Furthermore, the furan-modified resin includes a first furan-modified resin and a second furan-modified resin, and the weight ratio of the first furan-modified resin to the second furan-modified resin is 5 to 15.

[0008] Furthermore, the furan-modified resin includes a first furan-modified resin and a second furan-modified resin, and the weight ratio of the first furan-modified resin to the second furan-modified resin is 6 to 12.

[0009] Furthermore, the thermosetting resin is composed of bisphenol A benzoxazine resin, thermosetting bismaleimide, and brominated epoxy resin.

[0010] Furthermore, the weight ratio of the bisphenol A benzoxazine resin, the thermosetting bismaleimide, and the brominated epoxy resin is 2:1:5 to 2:1:7.

[0011] Furthermore, the high molecular resin is a high molecular resin grafted with an acid anhydride.

[0012] Furthermore, the high molecular resin is styrene maleic anhydride (SMA), styrene-ethylene / diene copolymer (SEBS), polypropylene (PP), polystyrene-polyethylene-polypropylene-polystyrene copolymer (SEPS), or styrene / isoprene copolymer (SIS).

[0013] Furthermore, the resin composition further comprises a solvent, and the solvent is toluene, γ-butyrolactone, methyl ethyl ketone, cyclohexanone, butanone, acetone, xylene, methyl isobutyl ketone, N,N-dimethylformamide, N,N-dimethylacetamide, N-methylpyrrolidone, or a mixture thereof.

[0014] To solve the above technical problems, another technical solution adopted by the present invention is to provide a prepreg, which comprises the aforementioned prepreg sheet; and a metal foil layer disposed on at least one surface of the prepreg sheet.

[0015] To solve the above technical problems, yet another technical solution adopted by the present invention is to provide a printed circuit board, which comprises the aforementioned laminated board.

[0016] One beneficial effect of the present invention is that the prepreg sheet, the laminated board, and the printed circuit board provided by the present invention can provide prepreg sheets, laminated boards, and printed circuit boards with excellent electrical properties, high heat resistance, high dimensional stability, and recyclability through the technical solutions of "the prepreg sheet is formed by impregnating a substrate in a resin composition" and "the resin composition comprises a furan-modified resin, a thermosetting resin, and a filler, wherein the furan-modified resin is obtained by reacting a high molecular resin with 2-furfurylamine".

[0017] To further understand the features and technical content of the present invention, please refer to the following detailed description of the present invention. However, the detailed description provided is only for reference and illustration, and is not used to limit the present invention. Detailed Embodiments

[0018] The following is a description of the embodiments of the present invention regarding "pre-impregnated sheet, laminate, and printed circuit board" through specific examples. Those skilled in the art can understand the advantages and effects of the present invention from the content disclosed in this specification. The present invention can be implemented or applied through other different specific embodiments, and various details in this specification can also be modified and changed based on different viewpoints and applications without departing from the concept of the present invention. The following embodiments will further elaborate on the related technical content of the present invention, but the disclosed content is not intended to limit the protection scope of the present invention.

[0019] It should be understood that although terms such as "first", "second", "third", etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms are mainly used to distinguish one element from another. Additionally, the term "or" used herein should, depending on the actual situation, possibly include any one or a combination of more of the associated listed items.

[0020] The present invention provides a resin composition, particularly a resin composition for printed circuit boards. The resin composition of the present invention comprises a furan-modified resin, a thermosetting resin, and a filler. Specifically, the furan-modified resin is a reaction product of a polymer resin and 2-furanmethanamine. The polymer resin is styrene maleic anhydride (SMA), styrene-ethylene / butylene-styrene (SEBS), polypropylene (PP), styrene-ethylene-propylene-styrene (SEPS), or styrene / isoprene styrene (SIS).

[0021] In an embodiment of the present invention, the furan-modified resin can be obtained by reacting styrene maleic anhydride (SMA) with 2-furanmethanamine. Styrene maleic anhydride is a polymer composed of styrene and maleic anhydride monomers. Olefin-toughened polymers have excellent electrical properties and good impact resistance, and the grafting of olefin-toughened polymers with maleic anhydride can increase compatibility. Therefore, styrene maleic anhydride can simultaneously have excellent electrical properties, high heat resistance, high dimensional stability, and specific reactivity of acid anhydride groups.

[0022] In another embodiment of the present invention, the furan-modified resin can be obtained by reacting styrene-ethylene / diene copolymer (SEBS) with 2-furfurylamine. SBS resin (Styrene Butadiene Styrene block polymer) is a triblock copolymer formed by the block polymerization of styrene and butadiene, which has the characteristic of being easy to process, but is susceptible to aging under the influence of O2, O3, UV, etc. SEBS is hydrogenated SBS, which has a high content of 1,2-vinyl structure, improves the disadvantage of easy aging, and increases the use temperature and compression set resistance.

[0023] In yet another embodiment of the present invention, the furan-modified resin can be obtained by reacting styrene-ethylene / diene copolymer (SEBS) with 2-furfurylamine. SEPS is a polymer of hydrogenated styrene and isoprene, which can improve the double bond content in the diene soft segment, thereby improving the disadvantage of easy aging and increasing the use temperature.

[0024] In still another embodiment of the present invention, the furan-modified resin can be obtained by reacting styrene / isoprene copolymer (SIS) with 2-furfurylamine. SIS has good thermal stability, excellent processability and elasticity, and has environmental protection characteristics.

[0025] For example, the furan-modified resin can be selected from the furan-modified resins synthesized by the methods described in Synthesis Example 1 to Synthesis Example 5 below. For example, two furan-modified resins can be selected and used in combination as the first furan-modified resin and the second furan-modified resin. Preferably, the weight ratio of the first furan-modified resin to the second furan-modified resin is 5 to 15. More preferably, the weight ratio of the first furan-modified resin to the second furan-modified resin is 6 to 12.

[0026] Synthesis Example 1

[0027] 200 g of SMA (S / M = 3 / 1) and 600 g of dimethylacetamide (DMAc) solvent were added to a 3 L four-neck separable reaction flask equipped with a heating device, a thermometer, a stirrer, and a condenser. The temperature was raised to about 60 °C and stirred evenly until completely dissolved. Under stirring, 50 g of furfurylamine (FA, purchased from ALDRICH) and 2 g of methylpyridine (3-PICOLINE) were added, and the temperature was raised to 90 °C until completely dissolved. The synthesis solution was heated and gradually raised to a temperature of 130 °C and reacted for 1 hour. The reaction formula is shown in Reaction Formula A. After complete reaction, the temperature was lowered to room temperature, and the graft polymer SMA-gF having the structure represented by General Formula (1) could be obtained.

[0028]

[0029]

[0030] In general formula (1), m represents an integer from 3 to 7, and n represents an integer from 7 to 3.

[0031] Synthesis Example 2

[0032] 200 g of MA-grafted SEBS and 600 g of toluene solvent were added to a 3 L four-neck separable reaction flask equipped with a heating device, a thermometer, a stirrer, and a condenser. The temperature was raised to about 60 °C and stirred evenly until completely dissolved. Under stirring, 50 g of furfurylamine (FA, purchased from ALDRICH) and 2 g of 3-picoline were added, and then the temperature was raised to 90 °C until completely dissolved. The synthetic solution was heated and gradually raised to 120 °C and reacted for 1 hour. The reaction formula is shown as Reaction Formula B. After the reaction was complete, the temperature was lowered to room temperature to obtain the graft polymer SEBS-gF having the structure represented by general formula (2).

[0033]

[0034] In general formula (2), m represents an integer from 1 to 3, n represents an integer from 1 to 3, X represents an integer from 1 to 5, and Y represents an integer from 1 to 3.

[0035] Synthesis Example 3

[0036] 200 g of maleic anhydride (MA)-grafted polypropylene (PP) and 600 g of toluene solvent were added to a 3 L four-neck separable reaction flask equipped with a heating device, a thermometer, a stirrer, and a condenser. The temperature was raised to about 60 °C and stirred evenly until completely dissolved. Under stirring, 50 g of furfurylamine (FA, purchased from ALDRICH) and 2 g of 3-picoline were added, and then the temperature was raised to 90 °C until completely dissolved. The synthetic solution was heated and gradually raised to 120 °C and reacted for 1 hour. After the reaction was complete, the temperature was lowered to room temperature to obtain the graft polymer PP-gF.

[0037] Synthesis Example 4

[0038] 200 g of maleic anhydride (MA) grafted polystyrene-ethylene-propylene-styrene copolymer (SEPS) and 600 g of toluene solvent were added to a 3-L four-neck separable reaction flask equipped with a heating device, a thermometer, a stirrer, and a condenser. The temperature was raised to about 60 °C and stirred evenly until completely dissolved. Under stirring, 50 g of furfurylamine (FA, purchased from ALDRICH) and 2 g of 3-picoline were added, and the temperature was raised to 90 °C to completely dissolve them. Then, the synthetic solution was heated and gradually raised to 120 °C and reacted for 1 hour. After complete reaction, the temperature was lowered to room temperature to obtain the grafted polymer SEPS-gF.

[0039] Synthesis Example 5

[0040] 200 g of maleic anhydride (MA) grafted styrene / isoprene copolymer (SIS) and 600 g of toluene solvent were added to a 3-L four-neck separable reaction flask equipped with a heating device, a thermometer, a stirrer, and a condenser. The temperature was raised to about 60 °C and stirred evenly until completely dissolved. Under stirring, 50 g of furfurylamine (FA, purchased from ALDRICH) and 2 g of 3-picoline were added, and the temperature was raised to 90 °C to completely dissolve them. Then, the synthetic solution was heated and gradually raised to 120 °C and reacted for 1 hour. After complete reaction, the temperature was lowered to room temperature to obtain the grafted polymer SIS-gF.

[0041] The thermosetting resin in the resin composition may be composed of a low hygroscopicity and low expansibility bisphenol A (BPA) type benzoxazine resin, a high heat resistance thermosetting bismaleimide, and a high toughness and high adhesion brominated epoxy resin. For example, the bisphenol A type benzoxazine resin may be BPA-BZ produced by Yuanhong, the thermosetting bismaleimide may be BMIKI-70 produced by Daiwa Chemical, and the brominated epoxy resin may be an artificial resin produced by Changchun. However, the above examples are only one possible embodiment and are not intended to limit the present invention.

[0042] In an embodiment of the present invention, in order to balance the electrical properties, heat resistance, and dimensional stability of the resin, the weight ratio of the bisphenol A type benzoxazine resin, the thermosetting bismaleimide, and the brominated epoxy resin is 2:1:5, 2:1:6, or 2:1:7. In addition, the filler in the resin composition may be silica (SiO2), alumina (Al2O3), talc, mica, boron nitride (BN), aluminum nitride (AlN), etc.

[0043] In the process of preparing the resin composition of the present invention, a solvent can be added so that the components of the resin composition, such as furan-modified resin, thermosetting resin, filler, toughening agent, etc., can be uniformly mixed with a homogenizer and dissolved or dispersed in the solvent to form a varnish-like form for subsequent processing and utilization. The solvent can be any inert solvent that can dissolve or disperse the components of the resin composition but does not react with these components. Solvents that can be used to dissolve or disperse the components of the resin composition include but are not limited to: toluene, γ-butyrolactone, methyl ethyl ketone, cyclohexanone, butanone, acetone, xylene, methyl isobutyl ketone, N,N-dimethyl formamide (DMF), N,N-dimethyl acetamide (DMAc), and N-methyl-pyrrolidone (NMP). Each solvent can be used alone or in combination. The amount of the solvent is not particularly limited. In principle, as long as it can uniformly dissolve or disperse the components of the resin composition therein. In a preferred embodiment of the present invention, a mixture of toluene, methyl ethyl ketone, and γ-butyrolactone is used as the solvent.

[0044] The resin composition of the present invention is prepared by the following method according to the weights shown in Table 1. Taking Example 1 as an example, according to the weights shown in Table 1, 30 g of the graft polymer SMA-gF and SEBS-gF 2.5 g, BPA-BZ 10 g, and 5 g of BMI KI-70 of Synthesis Example 1 are added to 100 g of methyl ethyl ketone (MEK) and fully dissolved. Then, 30 g of brominated epoxy resin is taken and uniformly mixed and dissolved with a homogenizer. After it is completely dissolved, 35 g of silica is added, and continuously uniformly mixed and dispersed in the solvent with a homogenizer to form a varnish liquid. The above resin composition is coated.

[0045] Examples 2 to 9 are repeated with the same steps as Example 1 according to the weights shown in Table 1 to form a varnish-like resin composition.

[0046] Furthermore, the substrate is impregnated or coated with the resin composition, and the impregnated or coated substrate is dried to obtain a prepreg. Specifically, after the substrate is impregnated or coated, it can be heated and dried at 80°C to 180°C for 1 to 10 minutes to obtain a prepreg in a semi-cured state. In an embodiment of the present invention, 2116 reinforced fiberglass cloth is used as the reinforcing material (substrate), and it is heated and dried at 175°C for 2 to 15 minutes to obtain a prepreg in a semi-cured state.

[0047] In one embodiment, the substrate can be a woven fiber cloth or a non-woven fiber cloth. The woven fiber cloth can be woven from glass fiber, metal fiber, liquid crystal polymer fiber, synthetic fiber or natural fiber. The material of the glass fiber can be E-glass, R-glass, ECR-glass, C-glass or Q-glass. The material of the liquid crystal polymer fiber can be wholly aromatic polyamide, wholly aromatic polyester or polyindole. The material of the synthetic fiber can be polyvinyl alcohol, polyester, polyacrylic acid or polytetrafluoroethylene. The material of the natural fiber can be cotton cloth, linen cloth and felt. The material of the non-woven fiber cloth can be polytetrafluoroethylene, quartz, alumina, aluminum nitride, glass material, liquid crystal polymer or any combination thereof. However, the present invention is not limited thereto. In a preferred embodiment of the present invention, the substrate is a 2116 reinforced glass fiber cloth.

[0048] The present invention can also provide a laminate and a printed circuit board. The laminate is a metal foil laminate, which is obtained by laminating the aforementioned prepreg and metal foil layer by layer. For example, four prepregs are laminated, and a 0.5 ounce copper foil is laminated on each of the outermost layers on both sides to form a laminate, and then placed in a hot press for high-temperature hot pressing and curing. In one embodiment, the aforementioned laminate is heated to 200°C to 220°C at a heating rate of 3.0°C / minute, and at this temperature, it is hot pressed for 180 minutes under a full pressure of 15 kg / cm² (initial pressure 8 kg / cm²). Then it is cooled to room temperature to make a double-sided copper-clad laminate, and the laminate can be used to manufacture a printed circuit board.

[0049] Table 1 shows the compositions of Examples EX1 to EX9 of the resin composition of the present invention and the characteristics of the prepregs made.

[0050] Table 1

[0051]

[0052]

[0053] Table 2 shows the compositions of Comparative Examples C1 to C6 of the resin composition and the characteristics of the prepregs made.

[0054]

[0055]

[0056] In Table 1 and Table 2, BPA-BZ is a bisphenol A type benzoxazine resin produced by Yuanhong; the filler is 10um cut SiO2 produced by Silbrico; BMI KI-70 is a thermosetting bismaleimide produced by Daiwa Chemical; the brominated epoxy resin is an artificial resin produced by Changchun; the reinforcing material is E-Glass cloth 2116 produced by Taibo; the toughening agent is 100 or nano-core-shell resin (CSR); the copper foil is H1 0.5OZ produced by Nanya.

[0057] The coefficient of thermal expansion (CTE) in the Z-axis is measured according to the IPC-TM-650-2.4.24 test specification. Using a thermal mechanical analyzer (TMA), the coefficient of thermal expansion (CTE) of the sample to be tested at a temperature below Tg is measured, and the rate of change of the coefficient of thermal expansion in the Z-axis direction (z-CTE) is obtained. z-CTE is measured in the temperature range of 50°C to 260°C, and the unit is %.

[0058] The peel strength refers to the adhesion of the metal foil to the laminated prepreg. In this test, a copper foil with a width of 1 / 8 inch is vertically peeled off from the board surface, and the strength required is used to express the strength of the adhesion. The unit of the peel strength is pounds per inch (lbf / in).

[0059] For the heat resistance test, the dried metal foil laminate is immersed in a solder bath at 288°C for 100 seconds, and this process is repeated 3 times. If the appearance remains unchanged, it indicates excellent heat resistance and is recorded as "○"; if there are bubbles or bulges on the appearance, it indicates poor heat resistance and is recorded as "×".

[0060] For the drill white line test, 100 holes with a diameter of 1 mm are drilled mechanically, and the number of white lines and hole cracks is observed. The dielectric constant (Dk) is measured according to the IPC-TM-650 2.5.5 test specification. The dielectric constant represents the electronic insulation property of the fabricated film, and the lower the value, the better the electronic insulation property. The dielectric dissipation factor (Df) is measured according to the IPC-TM-650 2.5.5 test specification.

[0061] Advantages of the embodiments

[0062] One of the advantages of the present invention is that the prepreg, laminate, and printed circuit board provided by the present invention can provide prepregs, laminates, and printed circuit boards with excellent electrical properties, high heat resistance, high dimensional stability, and recyclability through the technical solutions of "the prepreg is formed by impregnating a substrate in a resin composition" and "the resin composition includes a furan-modified resin, a thermosetting resin, and a filler, wherein the furan-modified resin is obtained by reacting a polymer resin with 2-furfurylamine".

[0063] Furthermore, the furan-modified resin in the resin composition is a chemical modification in which an acid anhydride-grafted polymer resin reacts with 2-furfurylamine to form crosslinkable functional groups, which can further increase compatibility and achieve excellent heat resistance. More specifically, the resin composition of the present invention contains a furan-modified styrene maleic anhydride copolymer, which can maintain the required toughness without the additional use of a toughening agent.

[0064] In addition, the resin composition of the present invention may include more than one furan-modified resin, preferably the first furan-modified resin and the second furan-modified resin are used in combination, and the toughness and excellent heat resistance of the resin composition can be increased and applied to electronic and electrical products.

[0065] The content disclosed above is only a preferred and feasible embodiment of the present invention, and does not limit the protection scope of the claims of the present invention. Therefore, all equivalent technical changes made by using the content of the specification of the present invention are included in the protection scope of the claims of the present invention.

Claims

1. A prepreg sheet, characterized in that, The prepreg sheet is formed by impregnating a substrate in a resin composition, the resin composition including a furan-modified resin, a thermosetting resin, and a filler, wherein the furan-modified resin is obtained by reacting a polymer resin with 2-furfurylamine.

2. The prepreg sheet according to claim 1, characterized in that, The furan-modified resin includes a first furan-modified resin and a second furan-modified resin, and the weight ratio of the first furan-modified resin to the second furan-modified resin is 5 to 15.

3. The prepreg sheet according to claim 1, characterized in that, The furan-modified resin includes a first furan-modified resin and a second furan-modified resin, and the weight ratio of the first furan-modified resin to the second furan-modified resin is 6 to 12.

4. The prepreg sheet according to claim 1, characterized in that, The thermosetting resin is composed of a bisphenol A benzoxazine resin, a thermosetting bismaleimide, and a brominated epoxy resin.

5. The prepreg sheet according to claim 4, characterized in that, The weight ratio of the bisphenol A benzoxazine resin, the thermosetting bismaleimide, and the brominated epoxy resin is 2:1:5 to 2:1:

7.

6. The prepreg sheet according to claim 1, characterized in that, The polymer resin is a polymer resin grafted with an acid anhydride.

7. The prepreg sheet according to claim 6, characterized in that, The polymer resin is styrene maleic anhydride, styrene-ethylene / diene copolymer, polypropylene, polystyrene-polyethylene-polypropylene-polystyrene copolymer, or styrene / isoprene copolymer.

8. The prepreg sheet according to claim 1, characterized in that, The resin composition further includes a solvent, and the solvent is toluene, γ-butyrolactone, methyl ethyl ketone, cyclohexanone, butanone, acetone, xylene, methyl isobutyl ketone, N,N-dimethylformamide, N,N-dimethylacetamide, N-methylpyrrolidone, or a mixture thereof.

9. A laminate, characterized in that, The laminate includes: The prepreg sheet according to claim 1; and A metal foil layer disposed on at least one surface of the prepreg sheet.

10. A printed circuit board, characterized in that, The printed circuit board includes the laminate according to claim 9.

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