THERMOSETTING RESIN COMPOSITION AND PREPREG AND LAMINATED BOARD PREPARED THEREFROM

Abstract

A thermosetting resin composition and a prepreg and a laminated board prepared therefrom. The thermosetting resin composition contains the following components in parts by weight: 50-150 parts of a cyanate; 30-100 parts of an epoxy resin; 5-70 parts of styrene-maleic anhydride; 20-100 parts of a polyphenyl ether; 30-100 parts of a halogen-free flame retardant; 0.05-5 parts of a curing accelerator; and 50-200 parts of a filler. The prepreg and laminated board prepared from the thermosetting resin composition have comprehensive performances such as a low dielectric constant, a low dielectric loss, an excellent flame retardance, heat resistance and moisture resistance, etc., and are suitable for use in a halogen-free high-frequency multilayer circuit board.

Claims

1-10. (canceled)

11. A thermosetting resin composition comprising the following components in parts by weight: 50-150 parts of a cyanate, 30-100 parts of an epoxy resin, 5-70 parts of styrene-maleic anhydride, 20-100 parts of a polyphenyl ether, 30-100 parts of a halogen-free flame retardant, 0.05-5 parts of a curing accelerator, and 50-200 parts of a filler; the epoxy resin at least comprises an epoxy resin having the dicyclopentadiene alkyl structure as shown in the following chemical structural formula: ##STR00005##

12. The thermosetting resin composition claimed in claim 11, wherein the cyanate is at least one selected from the group consisting of the following chemical structures: ##STR00006## wherein X.sub.1 and X.sub.2 are each independently selected from at least one of R, Ar, SO.sub.2 and 0; R is selected from the group consisting of —C(CH.sub.3).sub.2—, —CH(CH.sub.3)—, —CH.sub.2— and substituted or unsubstituted dicyclopentadienyl; Ar is anyone selected from the group consisting of substituted or unsubstituted benzene, biphenyl, naphthalene, phenolic aldehyde, bisphenol A, bisphenol A phenolic aldehyde, bisphenol F and bisphenol F phenolic aldehyde; n is an integer of greater than or equal to 1; Y is an aliphatic functional group or aromatic functional group.

13. The thermosetting resin composition claimed in claim 11, wherein the epoxy resin is also anyone selected from the group consisting of bisphenol A type epoxy resin, bisphenol F type epoxy resin, biphenyl epoxy resin, alkyl novolac epoxy resin, dicyclopentadiene epoxy resin, bisphenol A type novolac epoxy resin, o-cresol type novolac epoxy resin, phenol type novolac epoxy resin, trifunctional epoxy resin, tetrafunctional epoxy resin, isocyanate modified epoxy resin, naphthalene type epoxy resin and phosphorus-containing epoxy resin, or a mixture of at least two selected therefrom.

14. The thermosetting resin composition claimed in claim 11, wherein the styrene-maleic anhydride has the chemical structure of ##STR00007## wherein x is 1-4, 6 and 8; n is 1-12; x and n both are integers.

15. The thermosetting resin composition claimed in claim 11, the polyphenyl ether has a number-average molecular weight of 1000-4000.

16. The thermosetting resin composition claimed in claim 11, wherein the halogen-free flame retardant is anyone selected from the group consisting of phosphazene, ammonium polyphosphate, tri-(2-carboxyethyl)phosphine, tri-(isopropylchloro)phosphate, trimethyl phosphate, dimethyl-methyl phosphate, resorcinol bis-xylyl phosphate, phosphorus-nitrogen compounds, melamine polyphosphate, melamine cyanurate, tri-hydroxyethyl isocyanurate, 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide and DOPO-containing novolac resin, or a mixture of at least two selected therefrom.

17. The thermosetting resin composition claimed in claim 11, wherein the curing accelerator is anyone selected from the group consisting of imidazoles, metal salts, tertiary amines or piperidine compounds, or a mixture of at least two selected therefrom.

18. The thermosetting resin composition claimed in claim 11, wherein the curing accelerator is anyone selected from the group consisting of 2-methylimidazole, undecyl imidazole, 2-ethyl-4-methylimidazole, 2-phenyl-imidazole, 1-cyanoethyl substituted imidazole, benzyldimethylamine, cobalt acetylacetonate, copper acetylacetonate and zinc isooctanoate, or a mixture of at least two selected therefrom.

19. The thermosetting resin composition claimed in claim 11, wherein the filler is an inorganic or organic filler.

20. The thermosetting resin composition claimed in claim 11, wherein the filler is an inorganic filler, which is anyone selected from the group consisting of aluminum hydroxide, alumina, magnesium hydroxide, magnesium oxide, aluminum oxide, silicon dioxide, calcium carbonate, aluminum nitride, boron nitride, silicon carbide, titanium dioxide, zinc oxide, zirconium oxide, mica, boehmite, calcined talc, talc powder, silicon nitride and calcined kaolin, or a mixture of at least two selected therefrom.

21. The thermosetting resin composition claimed in claim 11, wherein the filler is an organic filler, which is anyone selected from the group consisting of polytetrafluoroethylene powder, polyphenylene sulfide and polyethersulfone powder, or a mixture of at least two selected therefrom.

22. The thermosetting resin composition claimed in claim 11, wherein the filler has a particle size of 0.01-50 μm.

23. A prepreg prepared from the thermosetting resin composition claimed in claim 11, wherein the prepreg comprises a matrix material, and the thermosetting resin composition attached thereon after impregnation and drying.

24. The prepreg claimed in claim 23, wherein the matrix material is a non-woven or woven glass fiber cloth.

25. A laminate comprising the prepreg claimed in claim 23.

26. A printed circuit board comprising the laminate claimed in claim 25.

Description

EMBODIMENTS

[0042] The technical solution of the present invention will be further described below by the specific embodiments.

[0043] Those skilled in the art shall know that the examples are merely illustrative of the present invention and should not be construed as specifically limiting the present invention.

[0044] Preparation Example: Synthesis of dicyclopentadiene alkyl phenol epoxy resin 270.0 g of p-(1,1,3,3-tetramethyl)butylphenol was added into a four-necked flask (500 mL) equipped with a polytetrafluoroethylene stirrer, a thermometer and a reflux condenser, heated and dissolved in water bath. 1.83 g of boron trifluoride•diethyl ether was added into the 500 mL four-necked flask, and 50.1 g of dicyclopentadiene was added to a dropping funnel to control the dropping speed so that all the dicyclopentadiene was added dropwise within 2 h. The mixture was heated to 100° C., held for 4 h, cooled to room temperature, and then heated to a certain temperature to distill excess dicyclopentadiene and p-(1,1,3,3-tetramethyl)butylphenol. The product is dicyclopentadiene alkyl phenol resin.

[0045] The dicyclopentadiene alkyl phenol resin obtained in the previous step was placed in a four-necked flask. 100.0 g of epichlorohydrin was weighed, added slowly, dissolved and heated. 1 mol of KOH solution having a mass fraction of 33% was added to a dropping funnel, added dropwise within 1 h by controlling the speed. The reaction temperature was controlled at 100° C. After adding dropwise, the temperature was held for 4 h. After cooling, water-washing, heating to 120° C., excessive epichlorohydrin was distilled to obtain the dicyclopentadiene alkyl phenol epoxy resin as shown in the following chemical formula:

##STR00004##

[0046] Examples Process for preparing copper clad laminates

[0047] A cyanate, an epoxy resin, styrene-maleic anhydride, a polyphenylene ether, a halogen-free flame retardant, a curing accelerator, a filler and a solvent were put into a container and stirred to make the mixture uniformly into a glue. The solid content of the solution was adjusted to 60%-70% with the solvent to obtain a glue solution, i.e. a thermosetting resin composition glue solution. A 2116 electronic grade glass cloth was impregnated with the glue, baked into a prepreg by an oven. 6 pieces of 2116 prepregs were covered with electrolytic copper foils having a thickness of 35 μm on both sides, vacuum-laminated in a hot press, cured at 190° C. for 120 min to obtain copper clad laminates.

[0048] The components and contents thereof (based on parts by weight) in Examples 1-6 and Comparison Examples 1-5 are shown in Table 1. The component codes and the corresponding component names are shown as follows. [0049] (A) Cyanate: HF-10(Product name from Shanghai Hui Feng trading) [0050] (B) Epoxy resin [0051] (B-1) Dicyclopentadiene alkyl phenol epoxy resin synthesized in the preparation example [0052] (B-2) Biphenyl epoxy resin: NC-3000-H (Product name from Nippon Kayaku); [0053] (B-3) Dicyclopentadiene epoxy resin: HP-7200H (Product name from Dainippon Ink and Chemicals) [0054] (C) Styrene-maleic anhydride oligomer: SMA-EF40 (Product name from Sartomer); [0055] (D-1) Polyphenyl ether having a low molecular weight: MX90 (Product name from SABIC Innovative Plastics) having a number-average molecular weight of 1000-4000; [0056] (D-2) Polyphenyl ether having a high molecular weight: Sabic640-111(Product name from SABIC Innovative Plastics) having a number-average molecular weight of 15000-20000; [0057] (E) Halogen-free flame retardant; [0058] (E-1) PX-200 (Product name from Daihachi Chemical Industry Co.); [0059] (E-2) SPB-100 (Product name from Otsuka Chemical Co.); [0060] (G) Curing accelerator; [0061] (H) Filler: molten silica.

[0062] The processes for preparing CCLs in Examples 1-6 and Comparison Examples 1-5 are the same as those in the examples.

[0063] The glass transition temperature (Tg), peeling strength (PS), dielectric constant (Dk) and dielectric loss angle tangent (Tg), flame retardancy, dip soldering resistance and water absorption after PCT 2 h of the copper clad laminates prepared in Examples 1-6 and Comparison Examples 1-5 were tested by the following methods, and the test results are shown in Table 2.

[0064] The performance parameters are tested by the following methods. [0065] A Glass transition temperature (Tg): tested according to the DSC method as stipulated under IPC-TM-650 2.4.25 in accordance with DSC; [0066] B Peeling strength (PS): testing the peeling strength of the metal cover layer under the testing conditions of “after thermal stress” in the method of IPC-TM-650 2.4.8; [0067] C Dielectric constant (Dk) and dielectric loss angle tangent (Df): testing dielectric constant (Dk) and dielectric loss angle tangent (Df) under 1 GHz by the resonance method using a stripe line according to IPC-TM-650 2.5.5.5; [0068] D Flame retardancy: tested according to the UL-94 standard; [0069] E Dip soldering resistance and water absorption after PCT 2 h:

[0070] The copper clad laminate was immersed in a copper etching solution to remove the surface copper foils, and to evaluate the substrate. The substrate was placed in a pressure cooker and treated at 121° C. and 2 atm for 2 hours. After the water absorption was measured, the substrate was immersed in a tin furnace having a temperature of 288° C. The corresponding time was recorded when the substrate is bubbled or split. The evaluation was finished when the substrate had no foaming or stratification in the tin furnace for more than 5 min.

TABLE-US-00001 TABLE 1 Example Example Example Example Example Example Comparison Comparison Comparison Comparison Comparison 1 2 3 4 5 6 Example 1 Example 2 Example 3 Example 4 Example 5 A 100 100 100 100 50 150 100 100 100 100 100 B-1 30 60 100 60 40 100 20 60 B-2 20 60 60 B-3 20 100 C 42 42 42 42 5 70 42 42 70 42 42 D-1 50 50 50 50 20 100 50 50 50 D-2 50 E-1 20 20 20 20 36 20 20 20 20 20 E-2 45 45 45 45 30 64 45 45 45 45 45 G q.s q.s q.s q.s q.s q.s q.s q.s q.s q.s q.s H 110 110 110 110 50 200 110 110 110 110 110

TABLE-US-00002 TABLE 2 Compar- Compar- Compar- Compar- Compar- Exam- Exam- Exam- Exam- Exam- Exam- ison ison ison ison ison Test items ple 1 ple 2 ple 3 ple 4 ple 5 ple 6 Example 1 Example 2 Example 3 Example 4 Example 5 Tg(DSC) 187 189 184 186 185 188 190 187 193 190 187 (° C.) Peeling strength 1.45 1.42 1.48 1.52 1.45 1.42 1.50 1.45 1.26 1.42 1.41 (N/mm) Dielectric 3.6 3.6 3.6 3.6 3.6 3.6 3.8 3.8 3.7 3.9 3.7 constant(1 GHz) Dielectric loss 0.0041 0.0042 0.0042 0.0044 0.0043 0.0042 0.0052 0.0059 0.0042 0.0060 0.0045 (1 GHz) Combustibility V-0 V-0 V-0 V-0 V-0 V-0 V-0 V-0 V-0 V-0 V-0 PCT(min) >5 >5 >5 >5 >5 >5 >5 >5 3 3 >5 PCT water 0.32 0.31 0.28 0.30 0.29 0.31 0.35 0.34 0.35 0.35 0.35 absorption Processability Better Better Better Better Better Better Better Better Better Better Worse

[0071] It can be seen according to the data in Tables 1 and 2 that, [0072] (1) According to Examples 1-3, it can be seen that the PCT water absorptions in Examples 1-3 were 0.32, 0.31 and 0.28, respectively; the PCT water absorption in Example 3 was the lowest; it was found that, along with the increase of the content of epoxy resin (corresponding to Component B-1), the PCT water absorption of the substrate gradually decreased, so that its water absorption was significantly improved; [0073] (2) As can be seen from Example 2 and Comparison Example 1, the dielectric constant, dielectric loss and PCT water absorption of Example 2 were all lower than those of Comparison Example 1; and it was found that a lower dielectric constant, a lower dielectric loss, and a lower PCT water absorption could be obtained by using dicyclopentadiene alkyl phenol epoxy resin synthesized according to the present invention in Example 2 as compared to biphenyl epoxy resin in Comparison Example 1; [0074] (3) As can be seen from Example 3 and Comparison Example 2, the dielectric constant, dielectric loss and PCT water absorption of Example 3 were lower than those of Comparison Example 2; it was found that a lower dielectric constant, a lower dielectric loss, and a lower PCT water absorption could be obtained by using dicyclopentadiene alkyl phenol epoxy resin synthesized according to the present invention in Example 3 as compared to the commercial dicyclopentadiene epoxy resin in Comparison Example 2; [0075] (4) It can be seen from Example 5, Example 6 and Comparison Example 3 that the components to be used should be controlled within certain weight ranges, so that the substrates had excellent overall properties; the dielectric properties in Comparison Example 3 were almost the same as those in Examples 5 and 6, but Comparison Example 3 could not pass the 2 h PCT test; it can be seen that Comparison Example 3 would affect the 2 h PCT test of the substrate when using less than 30 parts by weight of epoxy resin; [0076] (5) As can be seen from Example 2 and Comparison Example 4, the dielectric constant, dielectric loss and PCT water absorption in Example 2 were all lower than those in Comparison Example 4; Comparison Example 4 was not able to pass the 2-hour PCT test; it can be seen that the dielectric properties in Example 2 were remarkably improved after adding a polyphenyl ether having a low molecular weight as compared to Comparison Example 4 in which a polyphenyl ether having a low molecular weight was not added; moreover, Example 2 could pass the 2 h PCT test; by comparing Example 2 with Comparison Example 5, it can be found that, although their overall properties were equivalent, the use of a polyphenylene ether having a high molecular weight resulted in poor processability.

[0077] According to Examples 1 to 6, it was found that the laminates prepared by using the thermosetting resin composition of the present invention have a dielectric constant of 3.6 or less, a dielectric loss of 0.0041 to 0.0044, and have excellent flame retardancy, heat resistance, moisture resistance and other comprehensive performances. The flame retardancy thereof can reach the V-0 standard in the flame retardant test UL-94, and PCT water absorption is 0.28-0.32. Thus they are suitable for use in halogen-free high-frequency multilayer circuit boards.

[0078] In summary, the thermosetting resin composition of the present invention has a low dielectric constant, low dielectric loss, excellent heat resistance and cohesiveness while ensuring halogen-free flame retardancy, and is suitable for use in halogen-free high frequency multilayer circuit boards.

[0079] Certainly, the above-described examples are merely illustrative examples of the present invention and are not intended to limit the implement scope of the present invention. Therefore any equivalent changes or modifications according to the principles within the patent scope of the present invention are all included in the scope of the present patent.