Low dielectric resin composition capable of improving processability, prepreg sheet, and metal laminate

Abstract

The invention discloses a low-dielectric resin composition capable of improving processability, a prepreg sheet and a metal laminated plate. The low-dielectric resin composition comprises a resin system, a halogen-free flame retardant, hollow spherical silicon dioxide and a coupling agent. The resin system includes a polyphenylene ether resin, a cross-linking agent, and a vinyl-containing elastomer added in specific weight percentages. The hollow spherical silica has a specific gravity of 0.4 g / cm3 to 0.6 g / cm3 and an average particle diameter D50 in a range of 2.0 [mu] m to 3.0 [mu] m. Therefore, after the low-dielectric resin composition is cured, the dielectric constant (Dk) at the frequency of 10 GHz ranges from 2.75 to 3.05, and the dielectric loss factor (Df) is smaller than 0.002. On the basis of the low-dielectric resin composition, the invention also discloses a pre-impregnated sheet and a metal laminated plate using the low-dielectric resin composition.

Description

Technical Field

[0001] The present application relates to a resin composition and its applications, in particular to a low-dielectric resin composition capable of improving processability, and a prepreg sheet and a metal laminate made of this low-dielectric resin composition. Background Art

[0002] Advanced driver assistance systems (ADAS) can give drivers enough time to take contingency measures to prevent accidents. With the improvement of the technical level and the cost reduction of millimeter-wave radar (mmWave Radar), millimeter-wave radar has begun to play a role in the ADAS sensor process to continuously sense the environment around the vehicle body during driving.

[0003] The substrates used in existing millimeter-wave radars are mainly divided into fluororesin substrates and thermosetting resin substrates. Among them, due to the characteristics of the resin, for example, the processability of polytetrafluoroethylene (PTFE) is poor, it is very difficult to perform processing such as drilling and copper plating when used for laminate production, and special manufacturing and processing equipment is required, so there is a problem of too high cost. In addition, since fluororesin is a thermoplastic resin, it is difficult for electronic materials using fluororesin to be co-molded with electronic materials using general thermosetting resins (such as epoxy resins), which is restricted in practical applications. The thermosetting resin substrate mainly reduces the dielectric constant (Dk) of the substrate to a relatively low level by introducing hollow glass spheres. However, after introducing hollow glass spheres, not only the uniformity of drilling and copper plating is poor, but also the value of the dielectric loss factor (Df) increases. Summary of the Invention

[0004] One of the objectives of the present application is to provide, in view of the deficiencies of the prior art, a low-dielectric resin composition capable of improving processability, which is beneficial to the low transmission loss and processability of electronic materials, so as to meet the application requirements of millimeter waves. The present application also discloses a prepreg sheet and a metal laminate using the above low-dielectric resin composition.

[0005] In order to achieve the above invention objective, one of the technical solutions adopted in the present application is to provide a low-dielectric resin composition capable of improving processability, including a resin system of component (A), a halogen-free flame retardant of component (B), hollow spherical silica of component (C), and a coupling agent of component (D). Based on the total weight of the resin system, the resin system contains 10 wt% to 60 wt% of polyphenylene ether resin, 5 wt% to 30 wt% of crosslinking agent, and 20 wt% to 50 wt% of vinyl-containing elastomer. The specific gravity of the hollow spherical silica is 0.4 g / cm 3 to 0.6 g / cm 3And the average particle size D50 is in the range of 2.0 μm to 3.0 μm. In the low dielectric resin composition, with respect to 100 parts by weight of the resin system, the amount of the halogen-free flame retardant is 20 phr to 45 phr, the amount of the hollow spherical silica is 5 phr to 15 phr, and the amount of the coupling agent is 0.1 phr to 5 phr. Additionally, after the low dielectric resin composition is cured, the dielectric constant (Dk) at a frequency of 10 GHz is in the range of 2.75 to 3.05 and the dielectric loss factor (Df) is less than 0.002.

[0006] Furthermore, the vinyl-containing elastomer is selected from the group consisting of: polybutadiene, styrene-butadiene copolymer, styrene-butadiene-styrene block copolymer, and styrene-butadiene-divinylbenzene copolymer.

[0007] Furthermore, the vinyl-containing elastomer is a styrene-butadiene-styrene block copolymer, and its weight average molecular weight is in the range of 3500 g / mol to 5500 g / mol.

[0008] Furthermore, the styrene-butadiene-styrene block copolymer has 5 mol% to 40 mol% of styrene units. Additionally, based on 100% of all the vinyl groups in the styrene-butadiene-styrene block copolymer, the content of 1,2-vinyl groups in the styrene-butadiene-styrene block copolymer is in the range of 60% to 90%, and the content of 1,4-vinyl groups is in the range of 10% to 40%.

[0009] Furthermore, the hollow spherical silica is surface-modified with at least one functional group of acrylic group or vinyl group.

[0010] Furthermore, the crosslinking agent is selected from the group consisting of: triallyl cyanurate (TAC), triallyl isocyanurate (TAIC), trimethallyl isocyanurate (TMAIC), diallyl phthalate, divinylbenzene, and 1,2,4-triallyl trimellitate.

[0011] Furthermore, the low dielectric resin composition further includes general spherical silica of component (E), and its specific gravity is 2.0 g / cm 3 to 2.5 g / cm 3In addition, with respect to 100 parts by weight of the resin system, the amount of the spherical silica is generally 85 phr to 95 phr.

[0012] Furthermore, the average particle diameter D50 of the spherical silica is generally in the range of 2.0 μm to 3.0 μm.

[0013] Furthermore, the halogen-free flame retardant is a compound having the structure shown in the following formula (I):

[0014]

[0015] It is characterized in that R1 represents a covalent bond, -CH2-,

[0016] wherein R2, R3, R4, and R5 are each independently H, an alkyl group, or

[0017] Another object of the present application is to provide a prepreg sheet, which is obtained by coating or impregnating a reinforcing material with the low-dielectric resin composition described above.

[0018] Another object of the present application is to provide a metal laminate, which is obtained by laminating the prepreg sheet described above with a metal layer, or by coating the low-dielectric resin composition described above on a metal layer.

[0019] Generally speaking, the low-dielectric resin composition provided by the present application, by virtue of "the resin system contains 10% to 60% by weight of polyphenylene ether resin, 5% to 30% by weight of a crosslinking agent, and 20% to 50% by weight of a vinyl-containing elastomer based on the total weight of the resin system", "with respect to 100 parts by weight of the resin system, the amount of the hollow spherical silica is 5 phr to 15 phr", and "the specific gravity of the hollow spherical silica is 0.4 g / cm 3 to 0.6 g / cm 3 and the average particle diameter D50 is in the range of 2.0 μm to 3.0 μm", can achieve excellent electrical properties (Low Dk / Low Df) and moisture absorption heat resistance on the premise of meeting the halogen-free environmental protection requirements, maintain a stable low transmission loss for a long time, and can show good fluidity and glue filling property during the production of laminates, as well as improve the drilling processability and copper plating quality.

[0020] To further understand the features and technical content of the present application, please refer to the following detailed description and drawings of the present application. However, the provided drawings are only for reference and illustration, and are not used to limit the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 and Figure 2 is a schematic diagram of manufacturing a prepreg using the low dielectric resin composition capable of improving processability of the present application.

[0022] Figures 3 to 5 is a schematic diagram of manufacturing a metal laminate using the low dielectric resin composition capable of improving processability of the present application. Detailed embodiments

[0023] The following are embodiments of the present application related to "low dielectric resin composition, prepreg and metal laminate capable of improving processability" illustrated by specific examples. Those skilled in the art can understand the advantages and effects of the present application from the content disclosed in this specification. The present application can be implemented or applied through other different specific examples, 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 application. In addition, the drawings of the present application are only for simple schematic illustration and are not drawn according to actual dimensions. The following embodiments will further elaborate on the related technical content of the present application, but the disclosed content is not intended to limit the protection scope of the present application.

[0024] Unless otherwise defined, the terms used herein have the same meaning as commonly understood by those skilled in the art. The materials involved in each embodiment are commercially available or prepared according to the prior art unless otherwise specified. The operations or instruments involved in each embodiment are conventional operations or instruments in the art unless otherwise specified.

[0025] Due to the characteristics of the resin, it is difficult to perform processing such as drilling and copper plating when using a fluororesin substrate for laminate production, and special manufacturing and processing equipment is required, resulting in the problem of excessively high costs. In addition, fluororesin is a thermoplastic resin, and it is difficult for electronic materials using fluororesin to be co-molded with electronic materials using general thermosetting resins (such as epoxy resins), which is restricted in practical applications and is not sufficient to meet the requirements of advanced applications such as fifth-generation mobile communication (5G), advanced driver assistance systems (ADAS), and artificial intelligence (AI) for electronic materials. Therefore, the present application proposes a new concept: using a thermosetting resin, polyphenylene ether resin, in combination with a vinyl-containing elastomer (preferably styrene-butadiene-styrene block copolymer), and introducing hollow spherical silica (hollow silica) with a specific specific gravity and particle size to achieve low dielectric characteristics without compromising the characteristics required in practical applications, such as processability, moisture absorption and heat resistance, fluidity, and adhesiveness.

[0026] Specifically, the embodiments of the present application provide a low dielectric resin composition that embodies the above inventive concept and can improve processability, including a resin system of component (A), a halogen-free flame retardant of component (B), hollow spherical silica of component (C), and a coupling agent of component (D). Hereinafter, various components will be described in detail.

[0027] Resin system of component (A)

[0028] The resin system constituting the low dielectric resin composition of the present application, based on the total weight of the resin system, contains 10 wt% to 60 wt% of a polyphenylene ether resin, 5 wt% to 30 wt% of a crosslinking agent, and 20 wt% to 50 wt% of a vinyl-containing elastomer.

[0029] Furthermore, the molecular main chain end of the polyphenylene ether resin contains an unsaturated functional group, such as but not limited to a hydroxyl group, a vinyl group, a styryl group, a vinylbenzyl group, an allyl group, an acryloyl group, a methacrylate group, an epoxy group, and a maleimide group. The unsaturated functional group refers to a group that can undergo an addition polymerization reaction with other components having an unsaturated functional group, and the addition polymerization reaction can be initiated by light or heat in the presence of a polymerization initiator.

[0030] Specifically, the polyphenylene ether resin as the resin system of component (A) can be selected from the group consisting of: a polyphenylene ether resin containing a terminal hydroxyl group, a polyphenylene ether resin containing a terminal vinyl group, a polyphenylene ether resin containing a terminal styryl group, a polyphenylene ether resin containing a terminal vinylbenzyl group, a polyphenylene ether resin containing a terminal allyl group, a polyphenylene ether resin containing a terminal acryloyl group, a polyphenylene ether resin containing a terminal methacrylate group, a polyphenylene ether resin containing a terminal epoxy group, and a polyphenylene ether resin containing a terminal maleimide group. The above polyphenylene ether resins can be used alone or in combination.

[0031] Based on 100 wt% of the total weight of the resin system, the content of the polyphenylene ether resin can be 10 wt%, 15 wt%, 20 wt%, 25 wt%, 30 wt%, 35 wt%, 40 wt%, 45 wt%, 50 wt%, 55 wt%, or 60 wt%. The weight average molecular weight of the polyphenylene ether resin can be in the range of 1000 g / mol to 20000 g / mol, preferably in the range of 1000 g / mol to 10000 g / mol. If the molecular weight of the polyphenylene ether resin is too large, the fluidity and solvent solubility of the polyphenylene ether resin may become poor. If the molecular weight of the polyphenylene ether resin is too small, the electrical properties and thermal stability of the resin composition may be impaired.

[0032] In actual applications, two different polyphenylene ether resins can be used in combination in the resin system of component (A), such as but not limited to: a polyphenylene ether resin with a bismaleimide group at the end of the molecular main chain and a polyphenylene ether resin with a hydroxyl group, styryl group, methacrylate group or epoxy group at the end of the molecular main chain. Alternatively, three different polyphenylene ether resins can be used in combination in the resin system of component (A), such as but not limited to: a polyphenylene ether resin with a bismaleimide group at the end of the molecular main chain, a polyphenylene ether resin with a styryl group at the end of the molecular main chain and a polyphenylene ether resin with a methacrylate group at the end of the molecular main chain.

[0033] In the presence of the above-mentioned polyphenylene ether resin with an unsaturated functional group, the compatibility of the vinyl-containing elastomer in the resin composition can be improved, thereby increasing the upper limit of the addition amount of the vinyl-containing elastomer. Preferably, in the resin system of component (A), the amount of the polyphenylene ether resin is greater than the amount of the vinyl-containing elastomer. The preparation method of the above-mentioned polyphenylene ether resin with an unsaturated functional group is not the technical focus of this application, and those skilled in the art can obtain or complete it based on the content disclosed in this specification and the general knowledge they possess.

[0034] Furthermore, the vinyl-containing elastomer can react with the unsaturated functional group of the polyphenylene ether resin through the double bond of the vinyl to form a bond, so that the cured resin composition has good low dielectric properties, heat resistance and processability. It is also worth noting that compared with the existing low dielectric resin composition using liquid rubber and polyphenylene ether resin in combination, the low dielectric resin composition of this application uses a vinyl-containing elastomer and polyphenylene ether resin in combination, which can prevent the occurrence of phase separation.

[0035] Specifically, the vinyl-containing elastomer as the resin system of component (A) can be selected from the group consisting of: polybutadiene, styrene-butadiene copolymer (SBR), styrene-butadiene-styrene block copolymer (SBS) and styrene-butadiene-divinylbenzene copolymer. The above-mentioned vinyl-containing elastomers can be used alone or in combination.

[0036] Relative to the total weight of the resin system being 100% by weight, the content of the vinyl-containing elastomer can be 20% by weight, 25% by weight, 30% by weight, 35% by weight, 40% by weight, 45% by weight or 50% by weight. If the content of the vinyl-containing elastomer is less than 20% by weight, the resin composition cannot achieve the required electrical properties (such as low Dk value, low Df value) and physical and chemical properties (such as high glass transition temperature, low water absorption, good heat resistance). If the content of the vinyl-containing elastomer exceeds 50% by weight, the functions or effects of other components in the resin composition will be inhibited, resulting in some poor properties of the resin composition, such as flame retardancy.

[0037] Preferably, the vinyl-containing elastomer is a styrene-butadiene-styrene block copolymer having a weight-average molecular weight in the range of 3,500 g / mol to 5,500 g / mol, such as 3,500 g / mol, 4,000 g / mol, 4,500 g / mol, 5,000 g / mol, or 5,500 g / mol. Considering the physical properties of the resin composition after curing, the styrene-butadiene-styrene block copolymer has 5 mol% to 40 mol% of styrene units (the total monomer units of the styrene-butadiene-styrene block copolymer are 100 mol%). In addition, based on 100% of all the vinyl groups in the styrene-butadiene-styrene block copolymer, the content of 1,2-vinyl groups in the styrene-butadiene-styrene block copolymer is in the range of 60% to 90%, and the content of 1,4-vinyl groups is in the range of 10% to 40%. If the content of 1,2-vinyl groups in the styrene-butadiene-styrene block copolymer is less than 60%, the physical and chemical properties of the resin composition after curing, such as high glass transition temperature and heat resistance, may deteriorate.

[0038] Furthermore, the crosslinking agent is a component having an unsaturated functional group containing a double bond or a triple bond and capable of undergoing a crosslinking reaction with the above-mentioned polyphenylene ether resin and the vinyl-containing elastomer to form a three-dimensional network structure, such as but not limited to a monofunctional crosslinking agent (having only one unsaturated functional group in the molecule) or a polyfunctional crosslinking agent (having two or more unsaturated functional groups in the molecule). The type of the crosslinking agent is not particularly limited, and it is preferably compatible with the above-mentioned polyphenylene ether resin and the vinyl-containing elastomer.

[0039] Specifically, as the crosslinking agent for the resin system of component (A), it can be selected from the group consisting of: triallyl cyanurate (TAC), triallylisocyanurate (TAIC), trimethallyl isocyanurate (TMAIC), diallyl phthalate, 1,2,4-triallyltrimellitate, and divinylbenzene. The above crosslinking agents can be used alone or in combination.

[0040] Based on the total weight of the resin system being 100% by weight, the content of the crosslinking agent can be 5% by weight, 10% by weight, 15% by weight, 20% by weight, 25% by weight, or 30% by weight.

[0041] Halogen-free flame retardant of component (B)

[0042] The halogen-free flame retardant that constitutes the low-dielectric resin composition of this application can use a phosphorus-containing flame retardant, which is used to improve the flame retardancy of the prepared electronic materials and meet the requirements of halogen-free environmental protection. In practical applications, the phosphorus-containing flame retardant can be selected from the group consisting of the following: phosphate esters, phosphazenes, phosphine oxides, ammonium polyphosphate, melamine polyphosphate, melamine phosphate, 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO). The above-mentioned halogen-free flame retardants can be used alone or in combination. However, this application is not limited to the examples given above.

[0043] Examples of the phosphate ester halogen-free flame retardant include: triphenyl phosphate (TPP), tetraphenyl resorcinol bis(diphenylphosphate) (RDP), bisphenol A bis(diphenylphosphate) (BDP), Resorcinol bis(di-2,6-xylyl phosphate) (RXP).

[0044] Examples of the phosphazene halogen-free flame retardant include cyclic phosphazene compounds and linear phosphazene compounds.

[0045] Examples of the phosphine oxide halogen-free flame retardant include: tris(4-methoxyphenyl)phosphine oxide, diphenylphosphine oxide, triphenylphosphine oxide, and the phosphine oxide shown in the following formula (I) (the product with the model number PQ-60 of Jin Yi Chemical Industry). It is worth mentioning that in addition to the known flame retardant properties, the phosphine oxide with the structure of formula (I) can also bring the effect of improving the low-dielectric properties to the resin composition, which is beneficial to applications in the high-frequency region.

[0046]

[0047] Among them, R1 represents a covalent bond, -CH2-,

[0048] wherein, R2, R3, R4, and R5 are each independently H, an alkyl group, or

[0049] With respect to 100 parts by weight of the resin system of component (A), the amount of the halogen-free flame retardant of component (B) can be 20 phr to 45 phr, such as but not limited to 20 phr, 25 phr, 30 phr, 35 phr, 40 phr, or 45 phr. If the amount of the halogen-free flame retardant is less than 20 phr, the electronic material made from the resin composition cannot achieve the required flame retardant performance. If the amount of the halogen-free flame retardant is greater than 45 phr, it may negatively affect the electrical properties and practical properties such as water absorption and tear strength.

[0050] The hollow spherical silica of component (C)

[0051] The hollow spherical silica (hollow silica) that constitutes the low dielectric resin composition of this application has a specific specific gravity and particle size, enabling the resin composition to exhibit good fluidity and filling property (gap filling ability), and having good low dielectric properties and processability (drilling processability) after curing. Moreover, on this basis, the low dielectric resin composition of this application can achieve the properties required for laminates such as high-frequency and high-speed transmission characteristics and copper plating quality.

[0052] Specifically, the purity of the hollow spherical silica of component (C) is about 99% or more, the specific gravity is 0.4 g / cm 3 to 0.6 g / cm 3 and the average particle size D50 is in the range of 2.0 μm to 3.0 μm; the specific gravity of the hollow spherical silica is preferably 0.5 g / cm 3 . In addition, the hollow spherical silica of component (C) can be surface modified with at least one functional group among acrylic groups or vinyl groups to have good compatibility with the resin system of component (A), so that a larger amount can be added to the resin composition without impairing the practical properties required.

[0053] With respect to 100 parts by weight of the resin system of component (A), the amount of the hollow spherical silica of component (C) can be 5 phr to 15 phr, such as but not limited to 5 phr, 6 phr, 7 phr, 8 phr, 9 phr, 10 phr, 11 phr, 12 phr, 13 phr, 14 phr, or 15 phr.

[0054] The coupling agent of component (D)

[0055] The coupling agent that constitutes the low-dielectric resin composition of the present application may be at least one of a silane compound and a siloxane compound, which is used to increase the interfacial adhesion strength between the resin and a reinforcing material such as a fiber cloth, and to improve the compatibility between the resin and a reinforcing material such as a fiber cloth and an inorganic powder material.

[0056] Examples of the silane compound include amino silane, vinyl silane, acrylic silane, and epoxy silane. Examples of the siloxane compound include amino siloxane, vinyl siloxane, acrylic siloxane, and epoxy siloxane.

[0057] With respect to 100 parts by weight of the resin system of component (A), the amount of the coupling agent of component (D) may be from 0.1 phr to 0.5 phr, such as but not limited to 80 phr, 85 phr, 90 phr, 95 phr, 100 phr, 105 phr, 110 phr, 115 phr, or 120 phr.

[0058] The inorganic filler of component (E)

[0059] The low-dielectric resin composition of the present application may further include, as needed, an inorganic filler of component (E) to improve the mechanical strength, thermal conductivity, heat resistance, and other properties of the resin composition. If the dielectric constant and dielectric loss are to be maintained at a reduced level, the inorganic filler of component (E) may be selected from the group consisting of: general spherical silica different from hollow spherical silica, alumina, zinc oxide, titanium oxide, magnesium oxide, antimony oxide, beryllium oxide, aluminum nitride, boron nitride, calcium carbonate, potassium titanate, glass fiber, barium titanate, barium sulfate, aluminum hydroxide, and magnesium hydroxide. The above inorganic fillers may be used alone or in combination. However, the present application is not limited to the above examples.

[0060] With respect to 100 parts by weight of the resin system of component (A), the amount of the inorganic filler of component (E) may be from 80 phr to 120 phr, such as but not limited to 80 phr, 85 phr, 90 phr, 95 phr, 100 phr, 105 phr, 110 phr, 115 phr, or 120 phr.

[0061] Preferably, the inorganic filler of component (E) is general spherical silica, which can be prepared by a synthetic method. Additionally, the specific gravity of the general spherical silica may be 2.0 g / cm 3to 2.5 g / cm 3 preferably 2.2 g / cm 3 and the average particle diameter D50 is in the range of 2.0 μm to 3.0 μm. The amount of the spherical silica is 85 phr to 95 phr relative to 100 parts by weight of the resin system of the component (A).

[0062] Prepreg and Metal Laminate

[0063] Please refer to Figure 1 and Figure 2 This application also provides a prepreg 1 and a metal laminate using the above low-dielectric resin composition. Specifically, the prepreg 1 is obtained by coating or impregnating a reinforcing material 11 with a low-dielectric resin composition 12, attaching the low-dielectric resin composition 12 to the reinforcing material 11, and forming a semi-cured state through high-temperature heating. The reinforcing material 11 is, for example but not limited to, an electronic-grade general-purpose glass fiber cloth.

[0064] Cooperate with Figures 3 to 5 As shown, the metal laminate can be obtained by the following method: laminating the above prepreg 1 with at least one metal layer 2 (such as a copper foil layer) and bonding them together by hot pressing, or coating the above low-dielectric resin composition 12 on a metal layer 2 and fully drying and curing it. In the example of laminating the above prepreg 1 with at least one metal layer 2 (such as a copper foil layer), a predetermined number of prepregs 1 can be laminated, and a metal layer 2 can be laminated on at least one outer side of the formed laminate 1'.

[0065] In actual application, the metal layer 2 on the outer side of the metal laminate can be patterned through the process steps of the prior art to obtain a printed circuit board.

[0066] Performance Evaluation

[0067] Use toluene to form a thermosetting resin varnish from the resin compositions shown in Table 1 and Table 2. Then, using a South Asia glass fiber cloth (South Asia Plastics Corporation, product model NE1078) as the reinforcing material, impregnate the above thermosetting resin varnish at room temperature, and then dry it at 130 °C for several minutes to obtain a prepreg with a resin content of 70% by weight. Then, stack 4 prepreg bodies between 2 copper foils with a thickness of 35 μm and perform a hot pressing operation to obtain a copper foil substrate specimen with a thickness of 0.4 mm. The above hot pressing operation is to apply a pressure of 25 kg / cm 2 at a temperature of 85 °C and hold the temperature for 20 minutes, then heat it at a heating rate of 3 °C / min to 210 °C, hold the temperature for 120 minutes, and then slowly cool it to 130 °C. The obtained copper foil substrate specimen is evaluated for performance according to the following.

[0068] Glass transition temperature (°C): Measured by a dynamic mechanical analyzer (DMA).

[0069] Water absorption rate (%): After the specimen is heated in a pressure cooker at 2 atm and 120 °C for 120 minutes, calculate the weight change before and after heating.

[0070] T288 solder immersion resistance: After the specimen is heated in a pressure cooker at 2 atm and 120 °C for 120 minutes, immerse it in a solder bath at 288 °C and record the time when delamination occurs on the specimen.

[0071] Dielectric constant (Dk) and dielectric loss (Df): After removing the copper foil from the specimen, bake it in an oven at 105 °C for 30 minutes, and then use an analyzer (product model E4991A) from Agilent to measure the dielectric constant and dielectric loss at a frequency of 10 GHz.

[0072] Drilled hole copper plating uniformity: After the PCB drilled hole copper plating process, perform a cross-section slicing analysis on the sample and observe the copper plating uniformity under a scanning electron microscope (SEM).

[0073] In Table 1 or Table 2, the detailed data of each component are as follows:

[0074] Polyphenylene ether resin: Product with the trade name NORYL SA9000 from SABIC;

[0075] SBS resin: Product with the model SBS-Ctype from Nippon Soda Co., Ltd.;

[0076] Crosslinking agent: TAIC from Evonik;

[0077] Flame retardant: Product with the model PQ-60 from Jin Yi Chemical Co., Ltd.;

[0078] Hollow spherical silica: Product with the model HS-200 from AGC Japan;

[0079] General spherical silica: Silica prepared by the synthesis method, which is a product with the model EQ2410-SMC from Continental Three Times Co., Ltd.;

[0080] Hollow glass beads: Product with the model im16K from 3M;

[0081] Coupling agent: Product with the model Z-6030 from Dow Corning;

[0082] Peroxide: Product with the model Luperox F from ARKEMA;

[0083] Table 1

[0084]

[0085]

[0086] Table 2

[0087]

[0088]

[0089] As can be seen from Table 1 and Table 2 above, the resin composition of Comparative Example 1 only added general spherical silica and did not add hollow spherical silica. The Dk value of the obtained electronic material exceeded the specified range (2.75 to 3.05), that is, the required electrical properties were not achieved. Although the resin compositions of Comparative Examples 2 and 3 added extra hollow glass spheres, the Dk values of the obtained electronic materials could be maintained within the specified range, but it would not only cause poor uniformity of copper plating in drilling, but also lead to an increase in the Df value. In contrast, the resin compositions of Examples 1 to 4 used hollow spherical silica with a specific specific gravity and particle size to replace hollow glass spheres, and were used in combination with polyphenylene ether resin and SBS, which could achieve the low dielectric properties required for millimeter wave applications without damaging the processing quality (copper plating quality in drilling) of the laminate and the practical required properties such as water absorption and heat resistance.

[0090] [Advantages of the Embodiment]

[0091] The low dielectric resin composition provided by the present application, by virtue of "the resin system contains 10% to 60% by weight of polyphenylene ether resin, 5% to 30% by weight of crosslinking agent and 20% to 50% by weight of vinyl-containing elastomer based on the total weight of the resin system", "the amount of hollow spherical silica is 5 phr to 15 phr relative to 100 parts by weight of the resin system" and "the specific gravity of the hollow spherical silica is 0.4 g / cm 3 to 0.6 g / cm 3 and the average particle size D50 is in the range of 2.0 μm to 3.0 μm", can achieve excellent electrical properties (Low Dk / Low Df) and moisture absorption and heat resistance on the premise of meeting the halogen-free environmental protection requirements, maintain stable low transmission loss for a long time, and can show good fluidity and glue filling property during the production of the laminate, as well as improve the drilling processability and copper plating quality.

[0092] Furthermore, the low dielectric resin composition provided by the present application is an electronic material using polyphenylene ether resin. It is not only easy to be co-molded with electronic materials using other thermosetting resins (such as epoxy resin), but also can use existing manufacturing and processing equipment, so the cost can be reduced.

[0093] The content disclosed above is only the preferred and feasible embodiment of the present application, and does not limit the scope of the patent application of the present application. Therefore, all equivalent technical changes made by using the content of the specification and drawings of the present application are included in the scope of the patent application of the present application.

Claims

1. A low dielectric resin composition capable of improving processability, characterized in that: The low dielectric resin composition comprises: (A) a resin system comprising, based on the total weight of the resin system, 10 to 60 wt % of a polyphenylene ether resin, 5 to 30 wt % of a cross-linking agent, and 20 to 50 wt % of a vinyl-containing elastomer; (B) Halogen-free flame retardant; (C) Hollow spherical silica, with a specific gravity of 0.4 g / cm 3 Up to 0.6g / cm 3 and an average particle size D50 in the range of 2.0 μm to 3.0 μm; and (D) coupling agent; Wherein, relative to 100 parts by weight of the resin system, the amount of the halogen-free flame retardant is 20 phr to 45 phr, the amount of the hollow spherical silica is 5 phr to 15 phr, and the amount of the coupling agent is 0.1 phr to 5 phr. The dielectric constant (Dk) of the low dielectric resin composition after curing at a frequency of 10 GHz is in the range of 2.75 to 3.05 and the dielectric loss factor (Df) is less than 0.

002.

2. The low dielectric resin composition according to claim 1, characterized in that: The vinyl-containing elastomer is selected from the group consisting of polybutadiene, styrene-butadiene copolymer, styrene-butadiene-styrene block copolymer and styrene-butadiene-divinylbenzene copolymer.

3. The low dielectric resin composition according to claim 2, characterized in that: The vinyl-containing elastomer is a styrene-butadiene-styrene block copolymer, and its weight average molecular weight is in the range of 3500 g / mol to 5500 g / mol.

4. The low dielectric resin composition according to claim 3, characterized in that: The styrene-butadiene-styrene block copolymer has 5 mol% to 40 mol% of styrene units, and based on 100% of all vinyl groups in the styrene-butadiene-styrene block copolymer, the content of 1,2-vinyl groups is in the range of 60% to 90%, and the content of 1,4-vinyl groups is in the range of 10% to 40%.

5. The low dielectric resin composition according to claim 1, characterized in that: The hollow spherical silica is surface-modified by at least one functional group of an acrylic group or a vinyl group.

6. The low dielectric resin composition according to claim 1, characterized in that: The crosslinking agent is selected from the group consisting of: 1,3,5-triallyl cyanurate (TAC), triallyl isocyanurate (TAIC), trimethallylisocyanurate (TMAIC), diallyl phthalate, divinylbenzene and 1,2,4-Triallyl trimellitate.

7. The low dielectric resin composition according to claim 1, further comprising: (E) General spherical silica, its specific gravity is 2.0g / cm 3 Up to 2.5g / cm 3 , and relative to 100 parts by weight of the resin system, the amount of the general spherical silica is 85 phr to 95 phr.

8. The low dielectric resin composition according to claim 1, characterized in that: The average particle size D50 of the general spherical silica is in the range of 2.0 μm to 3.0 μm.

9. The low dielectric resin composition according to claim 1, characterized in that: The halogen-free flame retardant is a compound having a structure shown in the following formula (I): Wherein, R1 represents a covalent bond, -CH2-, Wherein, R2, R3, R4, R5 are each independently H, alkyl or 10. A prepreg sheet, characterized in that: The prepreg is made by coating or impregnating a reinforcing material with the low dielectric resin composition according to claim 1 .

11. A metal laminate plate, characterized in that: The metal laminate is made by laminating the prepreg according to claim 10 with a metal layer, or by coating the low dielectric resin composition according to claim 1 on a metal layer.

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