A thermosetting resin composition and its application

Abstract

The present invention provides a thermosetting resin composition and its application, wherein the thermosetting resin composition comprises the following components in parts by weight: component A: 8-40 parts of epoxidized silsesquioxane; component B: 10-50 parts of anhydride; component C: 30-80 parts of filler; the total weight of each component in the thermosetting resin composition is 100 parts. The thermosetting epoxy resin composition of the present invention has heat resistance, heat yellowing resistance and UV yellowing resistance after curing, and can meet the performance requirements of high whiteness, high temperature resistance whiteness and UV resistance whiteness of laminated boards in the LED field.

Description

Technical Field

[0001] The invention belongs to the technical field of printed circuit boards and relates to a thermosetting resin composition and application thereof. Background Art

[0002] In recent years, optical semiconductors represented by LEDs have been used in display applications, mobile devices, mobile phone backlight sources, sensors, and vehicle-mounted components. As the power and brightness of LEDs increase, laminates or metal foil-clad laminates used in printed wiring boards for LED installation are required to have excellent light resistance, especially high whiteness after high temperature and ultraviolet light exposure.

[0003] CN 101300318 discloses a high-refractive-index siloxane coating composition. The acid anhydride used in the composition is very easy to sublime, resulting in performance degradation. In addition, the epoxy-containing organic siloxane mentioned in the invention is not silsesquioxane. The reflectivity of the composition is still insufficient after ultraviolet light irradiation and high-temperature treatment.

[0004] CN 109181604A discloses the use of bisphenol A or bisphenol F epoxy resin, methyltetrahydrophthalic anhydride or nadic anhydride, and a catalyst to obtain a highly transparent epoxy resin adhesive. The anhydride in this solution is easily sublimated, resulting in performance degradation. In addition, the composition cannot further improve the reflectivity after high temperature and ultraviolet.

[0005] CN 108641650A discloses using bisphenol F epoxy, carboxyl-terminated butyl rubber, diaminodiphenyl sulfone, imidazole, surfactant, aluminum oxide, boron nitride, and ethylene glycol methyl ether for epoxy resin adhesive for LED circuits, but the system does not have high whiteness and has poor heat discoloration resistance after high-temperature treatment.

[0006] CN 101735617 B discloses a thermosetting composition of a polyisocyanate derivative containing epoxy groups and an organosiloxane containing 3,5-diepoxypropyltriisocyanurate groups. The composition is not prone to color change under the action of light and heat, but has poor moisture and heat resistance.

[0007] CN 101942073A discloses that a composition composed of alicyclic epoxy with special structure, cyclohexane 1,3,4-carboxylic acid 3,4-anhydride and methylhexahydrophthalic anhydride can effectively prevent the defect of depression after curing. However, since the anhydride used is easy to sublimate, a large amount of smoke is generated, which makes it difficult to produce laminated boards.

[0008] CN103415585B discloses an anisotropic conductive adhesive of silicone resin with epoxy groups, curing agent, conductive particles and reflective insulating particles to improve the luminous efficiency of light-emitting elements. However, due to the use of conductive particles, it cannot be used in laminated boards that play an insulating role.

[0009] WO2021230152A1 discloses a curing composition of silsesquioxane containing epoxy and mesogen units and an amine curing agent. The composition effectively improves the hardness and mechanical properties and can be used in electronic products. However, the composition turns yellow significantly after high-temperature treatment and UV treatment, which will seriously affect its application in LEDs.

[0010] Therefore, it is desired in the art to obtain a laminate or metal foil-clad laminate having high whiteness, high heat discoloration resistance, and high UV discoloration resistance to meet the performance requirements of printed circuit board substrates in the field of LEDs and the like. Summary of the invention

[0011] In view of the shortcomings of the prior art, the present invention aims to provide a thermosetting resin composition and its application. The thermosetting resin composition has heat resistance, heat yellowing resistance and UV yellowing resistance after curing, and can meet the performance requirements of high whiteness, high temperature resistance whiteness and UV resistance whiteness of laminated boards in the LED field.

[0012] To achieve this object, the present invention adopts the following technical solutions:

[0013] In one aspect, the present invention provides a thermosetting resin composition, comprising the following components in parts by weight:

[0014] Component A: 8-40 parts of epoxidized silsesquioxane; Component B: 10-50 parts of acid anhydride; Component C: 30-80 parts of filler;

[0015] The total weight of each component in the thermosetting resin composition is 100 parts.

[0016] In the present invention, epoxidized silsesquioxane is combined with anhydride to obtain a thermosetting epoxy resin composition having good heat resistance, heat yellowing resistance and UV yellowing resistance, and can meet the performance requirements of the LED field for high whiteness, high temperature resistance whiteness and UV resistance whiteness of laminates.

[0017] In the present invention, the epoxidized silsesquioxane does not contain the mesogenic group described in WO2021230152A1, so that the composition can be more easily impregnated into the glass cloth without the risk of precipitation, and also can obtain better heat-resistant yellowing performance.

[0018] In the present invention, in the thermosetting resin composition, the content of the epoxidized silsesquioxane can be 8 parts by weight, 10 parts by weight, 15 parts by weight, 20 parts by weight, 25 parts by weight, 30 parts by weight, 35 parts by weight or 40 parts by weight, as well as specific values ​​between the above values. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively lists the specific values ​​included in the range. In the present invention, if the content of the epoxidized silsesquioxane is less than 8 parts by weight, the composition will show obvious yellowing after ultraviolet irradiation and high temperature, and if the content is higher than 40 parts by weight, the heat resistance will be significantly deteriorated.

[0019] In the present invention, the content of the acid anhydride in the thermosetting resin composition can be 10 parts by weight, 15 parts by weight, 20 parts by weight, 25 parts by weight, 30 parts by weight, 35 parts by weight, 40 parts by weight, 45 parts by weight or 50 parts by weight, as well as specific values ​​between the above values. Due to the limited space and for the sake of simplicity, the present invention will no longer exhaustively list the specific values ​​included in the range. In the present invention, if the content of the acid anhydride is less than 10 parts by weight, the composition will show obvious yellowing after ultraviolet irradiation and high temperature, and if the content is higher than 50 parts by weight, the heat resistance will be significantly deteriorated.

[0020] In the present invention, the content of filler in the thermosetting resin composition can be 30 parts by weight, 35 parts by weight, 40 parts by weight, 45 parts by weight, 50 parts by weight, 55 parts by weight, 60 parts by weight, 65 parts by weight, 70 parts by weight, 75 parts by weight or 80 parts by weight.

[0021] Preferably, the chemical formula of the epoxidized silsesquioxane is R n (SiO 1.5 ) n , where R is Wherein R4 and R5 are the same or different and are selected from C1-C5 straight chain or branched chain alkylene, C1-C5 straight chain or branched chain alkyleneoxy; n=8, 10 or 12.

[0022] Preferably, when n=8, the epoxidized silsesquioxane has a structure shown in Formula I:

[0023]

[0024] Where R is Wherein R4 and R5 are the same or different and are selected from C1-C5 straight chain or branched chain alkylene, C1-C5 straight chain or branched chain alkyleneoxy.

[0025] In the present invention, the acid anhydride is selected from one or a combination of styrene-maleic anhydride and phosphoric anhydride.

[0026] Preferably, the styrene-maleic anhydride has a structure as shown in the following formula II:

[0027]

[0028] wherein n1:n2=0.8-19:1, for example 0.8:1, 1:1, 1.2:1, 2:1, 3:1, 5:1, 7:1, 9:1, 10:1, 12:1, 15:1, 17:1 or 19:1;

[0029] Preferably, the number average molecular weight of the styrene-maleic anhydride is 1000-50000, for example, 1000, 3000, 5000, 8000, 10000, 20000, 30000, 40000 or 50000, more preferably 1500-45000, further preferably 2000-40000.

[0030] Preferably, the phosphoric anhydride has a structure shown in the following formula III or formula IV:

[0031]

[0032] Wherein X1 and X2 are independently selected from Where R 11 and R 12 are the same or different and are selected from C1-C5 alkyl, benzoxazinyl, substituted or unsubstituted phenyl or substituted or unsubstituted naphthyl; R1 and R2 are the same or different and are selected from hydrogen, C1-C5 alkyl, substituted or unsubstituted phenyl or substituted or unsubstituted naphthyl; R3 is selected from hydrogen, C1-C5 alkyl or siloxy.

[0033] Preferably, the filler is selected from one or a combination of at least two of titanium dioxide, boehmite and aluminum hydroxide, preferably titanium dioxide;

[0034] Preferably, the filler has a median particle size of 0.1-10 μm, for example 0.1 μm, 0.5 μm, 1 μm, 2 μm, 3 μm, 4 μm, 5 μm, 6 μm, 7 μm, 8 μm, 9 μm or 10 μm.

[0035] Preferably, the thermosetting resin composition further comprises a catalyst.

[0036] Preferably, based on 100 parts by weight of the total weight of component A, component B and component C, the weight of the catalyst is 0.001-5 parts, for example, 0.001 parts, 0.01 parts, 0.05 parts, 0.1 parts, 1 parts, 2 parts, 3 parts, 4 parts or 5 parts, more preferably 0.02-4 parts, and further preferably 0.05-3 parts.

[0037] Preferably, the catalyst is selected from one or a combination of at least two of a tertiary amine, a tertiary phosphine, a quaternary ammonium salt, a quaternary phosphonium salt, an organic metal complex or an imidazole compound.

[0038] Preferably, the thermosetting resin composition may further include any one of alicyclic epoxy resin, bisphenol A epoxy resin, hydrogenated bisphenol A epoxy resin, or a combination of at least two thereof.

[0039] The thermosetting resin composition of the present invention may also use an antioxidant as needed. The antioxidant may be a phenolic, phosphorus, amine or sulfur antioxidant, and the following substances may be cited. 2,6-di-tert-butyl-4-methylphenol, 2,2'-methylenebis(4-methyl-6-tert-butylphenol), 2,6-di-tert-butyl-p-ethylphenol, antioxidant 1010, triphenyl phosphite, dialkyl phenyl phosphite, trinonylphenyl phosphite, antioxidant 4010, antioxidant AP, distearic acid thiodipropionate. These antioxidants may be used alone or in combination, and the weight percentage of the antioxidant is 0.01-3 parts based on the total weight percentage of the component A, component B and component C as 100 parts.

[0040] The thermosetting resin composition of the present invention may also use an ultraviolet light absorber as required. Examples thereof include 2-(2'-hydroxy-3'-tert-butyl-5'-methylphenyl)-5-chlorobenzotriazole, 2-(2'-hydroxy-3',5'-di-tert-butylphenyl)-5-chlorobenzotriazole, 2-(2'-hydroxy-3',5'-di-tert-amylphenyl)benzotriazole, 2-(2'-hydroxy-5'-tert-octyl)phenylbenzotriazole, 2-(2'-hydroxy-5'-methylphenyl)benzotriazole, 2,2'-methylenebis(4-tert-octyl-6-benzotriazolephenol), 2-(2'-hydroxy-3',5'-dicumylphenyl)benzotriazole, 2-(2'-hydroxy-3'-cumyl-5'-tert-octylphenyl)benzotriazole, 2-hydroxy-4-n-octyloxybenzophenone, and the like. These ultraviolet light absorbers can be used alone or in combination. Based on 100 parts by weight of the total weight of component A, component B and component C, the weight of the ultraviolet light absorber is 0.01-3 parts.

[0041] The thermosetting resin composition of the present invention may also use a fluorescent brightener as needed. The fluorescent brightener may be a stilbene type, a coumarin type, or a pyrazoline type fluorescent brightener, and the following substances may be cited: 1,4-bis(o-cyanostyryl)benzene, 1,4-bis(p-cyanostyryl)benzene, (1-o-cyanostyryl-4-p-cyanostyryl)benzene, 4-(2-benzoxazolyl)-4-(5-methyl-2-benzoxazolyl)stilbene, 4,4-bis(2-methoxystyryl)biphenyl, 2,2'-(2,5-diphenylthio)bis[5-(1,1-dimethylethyl)]benzoxazole, 2,2-(4,4-stilbene)bisbenzoxazole, 1,4-bis(benzoxazolyl-2-yl)naphthalene, and the like. These fluorescent whitening agents can be used alone or in combination. Based on 100 parts by weight of the total weight of component A, component B and component C, the weight of the fluorescent whitening agent is 0.01-3 parts.

[0042] In another aspect, the present invention provides a resin film, wherein the resin film is formed by semi-curing the resin composition as described above after being baked and heated.

[0043] In another aspect, the present invention provides a resin-coated copper foil, which is obtained by coating the resin composition as described above on a copper foil and heating the copper foil to form a semi-cured state.

[0044] In another aspect, the present invention provides a prepreg, the prepreg comprising a reinforcing material and the thermosetting resin composition as described above attached to the reinforcing material after being impregnated and dried.

[0045] In another aspect, the present invention provides a laminate comprising one or at least two laminated prepregs as described above.

[0046] In another aspect, the present invention provides a metal foil-clad laminate comprising one or at least two stacked prepregs as described above, and a metal foil covering one or both sides of the prepreg or the stacked prepregs.

[0047] In another aspect, the present invention provides a printed wiring board, which is produced by a method of forming a circuit by removing a portion of the metal foil on the surface of the metal foil-clad laminate as described above.

[0048] Compared with the prior art, the present invention has the following beneficial effects:

[0049] The present invention uses epoxidized silsesquioxane and anhydride to make the thermosetting resin composition have heat resistance, heat yellowing resistance and UV yellowing resistance after curing, and can meet the performance requirements of high whiteness, high temperature resistance whiteness and UV resistance whiteness of the laminate in the LED field. DETAILED DESCRIPTION

[0050] The technical solution of the present invention is further described below by specific implementation methods. It should be understood by those skilled in the art that the embodiments are only to help understand the present invention and should not be regarded as specific limitations of the present invention.

[0051] The sources of the raw materials used in the embodiments and comparative examples are as follows:

[0052] 1. Epoxidized silsesquioxane EP0408, from Hybrid Plastics, USA

[0053] 2. Epoxidized silsesquioxane EP0409, from Hybrid Plastics, USA

[0054] 3. Styrene maleic anhydride SMAEF10, from Sartomer

[0055] 4. Styrene maleic anhydride SMAEF40, from Sartomer

[0056] 5. Epoxy resin 2021P, from Daicel Japan

[0057] 6. Epoxy resin 7200H, from Nippon Kayaku

[0058] 7. Epoxy resin YX4000, from Mitsubishi Chemical of Japan

[0059] 8. Epoxy resin GELR128E, from Hongchang Electronic Materials Co., Ltd.

[0060] 9. Epoxy resin NPES901, from Nan Ya Plastics

[0061] 10. The epoxy-biphenyl-containing polyorganosilsesquioxane was prepared with reference to Example 1 of WO2021230152A1.

[0062] 11. Containing phosphoric anhydride, homemade

[0063] 100 g of nadic anhydride and 120 g of a phosphorus compound were reacted in the presence of 4.5 g of an initiator benzoyl peroxide at a reaction temperature of 135° C. for 7 hours, and the final product was a light yellow solid.

[0064] 12. Titanium dioxide TIPAQUE R-830 ​​comes from Ishihara, Japan.

[0065] Example 1

[0066] Add 25 parts of styrene maleic anhydride SMAEF40 and 55 parts of butanone into a beaker and stir to dissolve, then add 9 parts of epoxidized silsesquioxane EP0408, 66 parts of titanium dioxide TIPAQUE R-830, and 0.02 parts of 2-MI, stir well, and emulsify for 1 hour using an emulsifier to obtain a glue solution. The glue solution is impregnated into 2116 glass cloth, and then the glass cloth impregnated with the glue solution is baked at 150°C for 3 minutes to obtain a 2116 semi-cured sheet. After 4 2116 adhesive sheets are stacked, 18μm electrolytic copper foil is applied on both sides and sent to a press for pressing and curing. The curing conditions are 200°C and 90 minutes to obtain a copper-clad laminate.

[0067] The examples and comparative examples in Tables 1-3 below were prepared according to this method, and the amounts of substances used were as shown in the tables.

[0068] The laminated boards of the embodiments and comparative examples were tested for performance, and the testing methods are as follows:

[0069] (1) Resistance to high temperature yellowing: A 50 mm*50 mm laminate is made and treated at 260°C for 6 minutes. The whiteness is tested and the color is confirmed to be changed.

[0070] 1 means almost no discoloration;

[0071] 2 indicates slight discoloration;

[0072] 3 indicates moderate yellowing;

[0073] 4 indicates severe yellowing;

[0074] 5 indicates severe yellowing;

[0075] (2) UV yellowing resistance: A 50 mm*50 mm laminate was made and treated in a UV box for 24 hours. The whiteness was tested and the color was confirmed to be changed.

[0076] 1 means almost no discoloration;

[0077] 2 indicates slight discoloration;

[0078] 3 indicates moderate yellowing;

[0079] 4 indicates severe yellowing;

[0080] 5 indicates severe yellowing;

[0081] (3) Heat resistance: A 50mm*20mm copper laminate is immersed in a 300°C tin furnace for 10 minutes and then taken out for observation. If delamination or cracking occurs, it is recorded as Fail. If there is no abnormality, it is recorded as Pass.

[0082] Table 1

[0083]

[0084]

[0085] Table 2

[0086]

[0087] Table 3

[0088]

[0089] Comparative Example 7

[0090] The cured product prepared in Example 3 of WO2021230152A1 was used as a comparative example to test its resistance to high temperature yellowing, UV yellowing and heat resistance. The test results showed that the resistance to high temperature yellowing and UV yellowing of the cured product of Comparative Example 7 were 5 and 5, respectively. The cured product yellowed severely after high temperature and UV irradiation, and delamination and explosion occurred.

[0091] It can be seen from the data in Tables 1-3 that the thermosetting resin composition of the present invention can make the cured product have excellent heat resistance, heat yellowing resistance and UV yellowing resistance, and its high temperature yellowing resistance can reach level 1 or 2, and its UV yellowing resistance can reach level 1.

[0092] In Comparative Example 1, when the amount of epoxidized silsesquioxane was too much, the heat resistance failed, and yellowing after high temperature and UV irradiation also deteriorated. In Comparative Example 6, the amount of acid anhydride was too much, and the heat resistance failed. Compared with Example 3, Comparative Examples 2, 3, 4, and 5 used general epoxy resins, and the deterioration of high temperature resistance and yellowing after UV irradiation was more serious.

[0093] Compared with Example 1, the yellowing of the composition of WO2021230152A1 containing mesogen and epoxy silsesquioxane in Comparative Example 8 after high temperature and UV irradiation becomes relatively serious. Compared with Comparative Example 5, the composition of Comparative Example 9 after using DDM as a curing agent suffers from severe yellowing after high temperature and UV irradiation.

[0094] The applicant declares that the present invention illustrates the thermosetting resin composition and its application through the above embodiments, but the present invention is not limited to the above embodiments, that is, it does not mean that the present invention must rely on the above embodiments to be implemented. Those skilled in the art should understand that any improvement of the present invention, equivalent replacement of various raw materials of the product of the present invention, addition of auxiliary components, selection of specific methods, etc., all fall within the protection scope and disclosure scope of the present invention.

Claims

1. A thermosetting resin composition, characterized in that The thermosetting resin composition comprises the following components in parts by weight: Component A: 8-40 parts of epoxidized silsesquioxane; Component B: 10-50 parts of acid anhydride; Component C: 30-80 parts of filler; The total weight of each component in the thermosetting resin composition is 100 parts; The epoxidized silsesquioxane has a structure shown in Formula I: Where R is Wherein R4 and R5 are the same or different and are selected from C1-C5 straight chain or branched chain alkylene, C1-C5 straight chain or branched chain alkyleneoxy.

2. The thermosetting resin composition according to claim 1, characterized in that The acid anhydride is selected from one or a combination of styrene-maleic anhydride and phosphoric anhydride.

3. The thermosetting resin composition according to claim 2, characterized in that The styrene-maleic anhydride has a structure shown in the following formula II: Among them, n1:n2=0.8-19:

1.

4. The thermosetting resin composition according to claim 3, characterized in that: The number average molecular weight of the styrene-maleic anhydride is 1000-50000.

5. The thermosetting resin composition according to claim 4, characterized in that: The number average molecular weight of the styrene-maleic anhydride is 1500-45000.

6. The thermosetting resin composition according to claim 5, characterized in that: The number average molecular weight of the styrene-maleic anhydride is 2000-40000.

7. The thermosetting resin composition according to claim 2, characterized in that: The phosphoric anhydride has a structure shown in the following formula III or formula IV: Wherein, X1 and X2 are independently selected from Where R 11 and R 12 are the same or different and are selected from C1-C5 alkyl, benzoxazinyl, substituted or unsubstituted phenyl or substituted or unsubstituted naphthyl; R1 and R2 are the same or different and are selected from hydrogen, C1-C5 alkyl, substituted or unsubstituted phenyl or substituted or unsubstituted naphthyl; R3 is selected from hydrogen, C1-C5 alkyl or siloxy.

8. The thermosetting resin composition according to claim 1, characterized in that: The filler is selected from one or a combination of at least two of titanium dioxide, boehmite and aluminum hydroxide.

9. The thermosetting resin composition according to claim 1, characterized in that: The filler is titanium dioxide.

10. The thermosetting resin composition according to claim 1, characterized in that: The median particle size of the filler is 0.1-10 μm.

11. The thermosetting resin composition according to claim 1, characterized in that: The thermosetting resin composition further includes a catalyst.

12. The thermosetting resin composition according to claim 11, characterized in that: Based on 100 parts by weight of the total weight of the component A, the component B and the component C, the weight of the catalyst is 0.001-5 parts.

13. The thermosetting resin composition according to claim 12, characterized in that: The weight proportion of the catalyst is 0.05-3 parts.

14. The thermosetting resin composition according to claim 11, characterized in that: The catalyst is selected from one or a combination of at least two of tertiary amines, tertiary phosphines, quaternary ammonium salts, quaternary phosphonium salts, organic metal complexes or imidazole compounds.

15. The thermosetting resin composition according to claim 1, characterized in that: The thermosetting resin composition may further include any one of alicyclic epoxy resin, bisphenol A epoxy resin, hydrogenated bisphenol A epoxy resin, or a combination of at least two thereof.

16. A resin film, characterized in that: The resin film is formed by semi-curing the thermosetting resin composition according to any one of claims 1 to 15 by baking and heating.

17. A resin-coated copper foil, characterized in that: The resin-coated copper foil is obtained by coating the thermosetting resin composition according to any one of claims 1 to 15 on a copper foil and heating the composition to form a semi-cured state.

18. A prepreg, characterized in that: The prepreg comprises a reinforcing material, and the thermosetting resin composition according to any one of claims 1 to 15 attached to the reinforcing material after being impregnated and dried.

19. A laminated board, characterized in that: The laminate comprises one or at least two superimposed prepregs according to claim 18.

20. A metal foil-clad laminate, characterized in that: The metal foil clad laminate comprises one or at least two superimposed prepregs as claimed in claim 18, and a metal foil covering one side or both sides of the prepreg or the superimposed prepregs.

21. A printed circuit board, characterized in that: The printed wiring board is obtained by removing part of the metal foil on the surface of the metal foil-clad laminate as claimed in claim 20 to form a circuit.

Images