Novel bis(tetrazolyl)urea compounds

Abstract

Provision of novel bis(tetrazolyl)urea compounds. [Solution] A silane coupling agent comprising a compound represented by general formula (I), or a compound represented by general formula (I). TIFF2026106063000016.tif2074(In the formula, R is independently -(CH2) n - Represents Si(Y)3, where n independently represents an integer from 1 to 6, and Y independently represents an alkoxy group.

Description

[Technical Field]

[0001] The present invention relates to a novel bis(tetrazolyl)urea compound, a silane coupling agent containing the compound, and a surface treatment agent containing the compound. [Background technology]

[0002] In semiconductor package substrates, the conductor and the insulating resin layer are physically bonded using the irregularities on the conductor's surface. However, irregularities on the conductor surface increase resistance, making it unsuitable for high-speed transmission. To improve this, if the irregularities on the conductor surface are eliminated (roughened), the adhesion between the conductor and the insulating resin weakens, causing problems with the quality of the semiconductor package substrate. Therefore, one method to ensure adhesion between the conductor and the insulating resin layer in semiconductor package substrates is to treat the copper surface with a silane coupling agent.

[0003] Compounds having a trialkoxysilyl group and an azole ring are known as silane coupling agents. For example, Patent Document 1 describes a compound having a tetrazole ring. Patent Document 2 also describes a silane coupling agent that includes a compound having a structure in which the triazole rings of a (trialkoxysilyl)alkyltriazole compound are crosslinked with a phenylene group, an imino group, or an alkylene group. [Prior art documents] [Patent Documents]

[0004] [Patent Document 1] International Publication No. 2019 / 058773 [Patent Document 2] International Publication No. 2023 / 190264 [Overview of the project] [Problems that the invention aims to solve]

[0005] However, the adhesion performance of existing silane coupling agents is insufficient. In particular, the deterioration of adhesion performance in high-accelerated stress tests (HAST) is significant. Therefore, compounds with improved adhesion performance are desired.

[0006] The present invention aims to provide a compound with improved adhesion performance (particularly improved adhesion performance after HAST), a silane coupling agent containing the compound, and a surface treatment agent containing the compound. [Means for solving the problem]

[0007] The present invention relates to general formula (I)

[0008] [ka] (In the formula, R is independently -(CH2) n - Represents Si(Y)3, where n independently represents an integer from 1 to 6, and Y independently represents an alkoxy group. This relates to the compound shown.

[0009] It is preferable that Y is a methoxy group or an ethoxy group, and n is 3 or 4.

[0010] Furthermore, the present invention relates to a silane coupling agent containing a compound of formula (I).

[0011] The silane coupling agent is preferably used to bond two materials selected from metals, inorganic materials, and resin materials.

[0012] The silane coupling agent is more preferably used for bonding a metal to a resin material.

[0013] The aforementioned metal is preferably at least one selected from copper, aluminum, titanium, nickel, tin, iron, silver, gold, and alloys thereof.

[0014] It is more preferable that the metal is copper or a copper alloy.

[0015] The resin material is preferably at least one selected from acrylic resin, epoxy resin, olefin resin, polybenzoxazole resin, silicone resin, polyimide resin, phenolic resin, and bismaleimide resin.

[0016] The present invention also relates to a surface treatment agent containing a compound of formula (I).

[0017] The surface treatment agent is preferably used for the adhesion of two materials selected from metal, inorganic material, and resin material.

[0018] More preferably, the surface treatment agent is used for the adhesion between a metal and a resin material.

[0019] The metal is preferably at least one selected from copper, aluminum, titanium, nickel, tin, iron, silver, gold, and alloys thereof.

[0020] It is more preferable that the metal is copper or a copper alloy.

[0021] The resin material is preferably at least one selected from acrylic resin, epoxy resin, olefin resin, polybenzoxazole resin, silicone resin, polyimide resin, phenolic resin, and bismaleimide resin.

Embodiments for Carrying out the Invention

[0022] One embodiment of the present invention is general formula (I)

[0023]

Chemical Formula

[0024] In the compound of formula (I), the alkoxy group can be linear, branched, or cyclic alkoxy group. In the case of linear or branched alkoxy groups, alkoxy groups having 1 to 6 carbon atoms are preferred. Specifically, examples include methoxy, ethoxy, n-propoxy, i-propoxy, n-butoxy, i-butoxy, s-butoxy, t-butoxy, n-pentyloxy, and n-hexyloxy groups. In addition, cyclic alkoxy groups can be alkoxy groups having 3 to 6 carbon atoms. Specifically, examples include c-propoxy, c-butoxy, c-pentyloxy, and c-hexyloxy groups. Among these, methoxy or ethoxy groups are preferred.

[0025] Furthermore, in the compound of formula (I), n is an integer from 1 to 6. n can be appropriately set to maintain an appropriate distance between the tetrazole ring and the trialkoxysilyl group, thereby improving adhesion. n is preferably an integer from 2 to 6, more preferably from 2 to 5, and even more preferably 3 or 4.

[0026] In the compound of formula (I), Y is preferably a methoxy group or an ethoxy group, and n is preferably 3 or 4.

[0027] R is a (CH2) substituted with a tri(alkoxy)silyl group. n It is a group. The above explanation applies to the alkoxy group and n. Preferably, R is a group independently selected from -(CH2)3-Si(OCH3)3, -(CH2)3-Si(OCH2CH3)3, -(CH2)4-Si(OCH3)3, and -(CH2)4-Si(OCH2CH3)3. R may be the same group as each other.

[0028] Specific examples of compounds of formula (I) include, for example, 1,3-Bis(1-(3-(triethoxysilyl)propyl)-1H-tetrazole-5-yl)urea, 1,3-Bis(2-(3-(triethoxysilyl)propyl)-2H-tetrazole-5-yl)urea, Examples include 1-(1-(3-(triethoxysilyl)propyl)-1H-tetrazole-5-yl)-3-(2-(3-(triethoxysilyl)propyl)-2H-tetrazolyl-5-yl)urea.

[0029] Furthermore, other specific examples of compounds of formula (I) include: 1,3-Bis(1-(3-(trimethoxysilyl)propyl)-1H-tetrazole-5-yl)urea, 1,3-Bis(2-(3-(trimethoxysilyl)propyl)-2H-tetrazole-5-yl)urea, 1-(1-(3-(trimethoxysilyl)propyl)-1H-tetrazole-5-yl)-3-(2-(3-(trimethoxysilyl)propyl)-2H-tetrazolyl-5-yl)urea, 1,3-Bis(1-(4-(triethoxysilyl)butyl)-1H-tetrazole-5-yl)urea, 1,3-Bis(2-(4-(triethoxysilyl)butyl)-2H-tetrazole-5-yl)urea, Examples include 1-(1-(4-(triethoxysilyl)butyl)-1H-tetrazole-5-yl)-3-(2-(4-(triethoxysilyl)butyl)-2H-tetrazolyl-5-yl)urea.

[0030] Compounds of general formula (I) include the individual compounds mentioned above, as well as mixtures thereof. Furthermore, compounds of general formula (I) include isomers resulting from differences in the substitution position of substituent R in the tetrazole ring. Each isomer can be used isolated, or a mixture of isomers can be used.

[0031] The compound of formula (I) exhibits excellent adhesion to metals, inorganic materials, and resin materials. The compound of formula (I) has two tri(alkoxy)silyl groups in its molecule and a bis(tetrazolyl)urea structure. The two tri(alkoxy)silyl groups in the molecule are converted to hydroxysilyl groups by hydrolysis and then bond to metal surfaces such as copper. In addition, the bis(tetrazolyl)urea interacts with resin materials and metal surfaces, forming bonds. In this way, the compound of formula (I) is thought to exhibit high adhesion to metal surfaces and resin materials. For this reason, the compound of formula (I) is useful as a silane coupling agent and a surface treatment agent.

[0032] Furthermore, the compound of formula (I) exhibits superior adhesion compared to conventional compounds after high-speed accelerated life testing. The compound of formula (I) has a structure in which two tetrazole rings are cross-linked by urea, and it is believed that this structure strengthens the bond between materials, thereby improving adhesion.

[0033] The compound of formula (I) is the general formula (II)

[0034] [ka] (In the formula, the symbols have the same meaning as above.) It can be produced by condensing the compounds shown with N,N'-carbonyldiimidazole (hereinafter referred to as CDI).

[0035] The condensation reaction can be carried out in an organic solvent at room temperature or under heating.

[0036] Any solvent can be used as long as it does not affect the reaction. Examples include aromatic hydrocarbons such as toluene, ethers such as tetrahydrofuran and dioxane, amides such as dimethylformamide, and dimethyl sulfoxide. Among these, amides such as dimethylformamide can be preferably used.

[0037] The reaction can be carried out at room temperature or under heating, for example, at 20°C to 100°C, preferably 40°C to 80°C.

[0038] To produce the compound of formula (I) from the compound of formula (II), it is preferable to use CDI. The amount of CDI used is 0.2 to 1.2 molar equivalents, preferably 0.4 to 0.6 molar equivalents. Using other condensing agents or carbonylating agents instead of CDI results in insufficient reaction. Furthermore, other carbonylating agents require the addition of a base such as triethylamine to the reaction system. Using CDI allows the reaction to proceed sufficiently under mild, neutral conditions.

[0039] <Silane coupling agent> Another embodiment of the present invention relates to a silane coupling agent containing a compound represented by general formula (I).

[0040] The compound represented by formula (I) can be used to immobilize, for example, glass, silicon wafers, various metals, inorganic materials, resin materials, nucleic acids, proteins, antibodies, and other bio-related organic molecules, as long as it does not adversely affect adhesion.

[0041] Examples of metals include at least one selected from copper, aluminum, titanium, nickel, tin, iron, silver, gold, and alloys thereof.

[0042] Furthermore, the metal is preferably copper or a copper alloy, as these offer excellent durability, flexibility, and conductivity.

[0043] Furthermore, the resin material is preferably at least one selected from acrylic resin, epoxy resin, olefin resin, polybenzoxazole resin, silicone resin, polyimide resin, phenolic resin, and bismaleimide resin. In particular, epoxy resin can be suitably used.

[0044] This is because it has excellent strength, heat resistance, chemical resistance, and electrical properties, as well as excellent adhesion to metals such as copper.

[0045] Silane coupling agents can be prepared by conventional methods. For example, a silane coupling agent can be prepared by dissolving or dispersing an appropriate amount of the compound of formula (I) in a suitable solvent to form a solution or suspension. Other additives such as suitable resins, surfactants, preservatives, anti-discoloration agents, antioxidants, and light stabilizers may also be included, to the extent that they do not impair the effectiveness.

[0046] The solvent is not particularly limited as long as it is a solvent in which the compound of formula (I) dissolves. Examples include organic solvents or mixed solvents of organic solvents and water. Specific examples of organic solvents include hydrocarbon solvents such as benzene, toluene, hexane, and heptane; ether solvents such as tetrahydrofuran, 1,4-dioxane, and diethyl ether; ketone solvents such as acetone and methyl ethyl ketone; glycol solvents such as propylene glycol-1-monomethyl ether-2-acetate (PGMEA), ethylene glycol diethyl ether, and ethylene glycol monobutyl ether (EGBE); and halogen solvents such as chloroform and 1,2-dichloroethane. Preferably, glycol solvents such as propylene glycol-1-monomethyl ether-2-acetate (PGMEA), ethylene glycol diethyl ether, and ethylene glycol monobutyl ether (EGBE), and mixed solvents of glycol solvents and water are used.

[0047] The amount of compound (I) used is not particularly limited as long as it does not affect adhesion, but the amount of compound added to the solvent is preferably 0.001% to 10% by weight, and more preferably 0.01% to 5% by weight.

[0048] The means of bringing the silane coupling agent into contact with the surface of a metal, inorganic material, or resin material are not particularly limited and can be carried out according to conventional methods. For example, the silane coupling agent in solution or suspension may be sprayed or applied in an appropriate amount to the surface of the metal, inorganic material, or resin material. Alternatively, the metal, inorganic material, or resin material may be immersed in the silane coupling agent. When the metal, inorganic material, or resin material is immersed in a solution containing the silane coupling agent, the immersion time is preferably 10 to 120 seconds, and more preferably 50 to 90 seconds. In this way, for example, when the surface of a metal is treated with the silane coupling agent, a chemical conversion film in which the compound of formula (I) adheres closely is formed on the surface of the metal, improving adhesion to resin materials such as insulating films.

[0049] After treating a material selected from metals, inorganic materials, and resin materials with a silane coupling agent, the material may be bonded to other materials either before or after drying. Drying can be carried out according to conventional methods. For example, drying can be done by blowing compressed air or compressed nitrogen, or by leaving it to dry. The drying temperature is preferably 30°C to 150°C, and more preferably 90°C to 110°C. The drying time can be suitably carried out for 1 to 5 minutes.

[0050] For bonding materials such as metals, inorganic materials, and resin materials, it is preferable to use conventional methods such as press-bonding with a press machine. For example, press-bonding can be performed at 150°C to 190°C under a pressure of 1 MPa to 5 MPa for 60 to 120 minutes.

[0051] The silane coupling agent may be a combination of bis(tetrazolyl)urea compounds having different chemical structures from the chemical structure represented by general formula (I). Furthermore, the silane coupling agent according to the present invention can be used in combination with known silane coupling agents.

[0052] <Surface treatment agent> Another embodiment of the present invention relates to a surface treatment agent containing a compound represented by general formula (I).

[0053] The compound represented by formula (I) can be used as a surface treatment agent when bonding metals such as copper, inorganic materials, and resin materials such as insulating films. The surface treatment agent is preferably used to bond two materials selected from metals, inorganic materials, and resin materials, and more preferably to bond a metal and a resin material. For example, when the surface of a metal such as copper is treated with the surface treatment agent according to this embodiment, a chemical conversion film in which the compound of formula (I) adheres is formed on the surface of the copper, improving the adhesion between the metal such as copper and the resin material such as an insulating film.

[0054] The metal to be treated with the surface treatment agent is preferably at least one selected from copper, aluminum, titanium, nickel, tin, iron, silver, gold, and their alloys, and more preferably copper or a copper alloy.

[0055] The resin material to which the surface treatment agent is applied is preferably at least one selected from acrylic resin, epoxy resin, olefin resin, polybenzoxazole resin, silicone resin, polyimide resin, phenolic resin, and bismaleimide resin. Epoxy resin is particularly preferred.

[0056] The same explanation given for silane coupling agents above can be applied to other surface treatment agents.

[0057] In this specification, if isomers exist for the compounds exemplified, all possible isomers may be used unless otherwise specified.

[0058] Furthermore, in this specification, the compound represented by general formula (I) includes each of the compounds represented by the following formulas (Ia) to (Ic), and also includes mixtures of each of the compounds represented by the following formulas (Ia) to (Ic).

[0059] [ka] (In the formula, the symbols have the same meaning as above.)

[0060] [ka] (In the formula, the symbols have the same meaning as above.)

[0061] [ka] (In the formula, the symbols have the same meaning as above.)

[0062] In this specification, the compounds represented by general formula (II) include the compounds of formula (IIa) and the compounds of formula (IIb), and also include mixtures of these compounds.

[0063] [ka] (In the formula, the symbols have the same meaning as above.)

[0064] [ka] (In the formula, the symbols have the same meaning as above.) [Examples]

[0065] The present invention will be described based on examples, but the present invention is not limited to these examples.

[0066] Reference example 1 Synthesis of 1-(3-(triethoxysilyl)propyl)-1H-tetrazole-5-amine (compound 1a) and 2-(3-(triethoxysilyl)propyl)-2H-tetrazole-5-amine (compound 1b) A mixture of the above compounds was obtained by treating 5-amino-1H-tetrazole and 3-chloropropyltriethoxysilane according to the method described in Example 7 of Patent Document 1. Specifically, 5-amino-1H-tetrazole (8.51 g, 100 mmol) was dissolved in dimethylformamide (40.0 ml), a 21 wt% ethanol solution of sodium ethoxide (38.7 ml, 104 mmol) was added, and the mixture was stirred at 70°C for 1 hour. Then, 3-chloropropyltriethoxysilane (24.0 g, 100 mmol) was added, and the mixture was stirred at 100°C for 20 hours. After that, post-treatment according to a conventional method was performed to obtain a mixture of 1-(3-(triethoxysilyl)propyl)-1H-tetrazole-5-amine (compound 1a) and 2-(3-(triethoxysilyl)propyl)-2H-tetrazole-5-amine (compound 1b) (22.8 g, 78.8 mmol). The mixing ratio of compound 1a and compound 1b was 38:62 by weight.

[0067] [ka]

[0068] [ka]

[0069] A mixture of compound (1a) and compound (1b) was used as the raw material compound in Example 1 below. Furthermore, a mixture of compound (1a) and compound (1b) was used as the comparative compound in the adhesion test in Example 2 below.

[0070] Example 1: Synthesis of 1,3-bis(3-(triethoxysilyl)propyltetrazolyl)urea A mixture of 1-(3-(triethoxysilyl)propyl)-1H-tetrazol-5-amine (Compound 1a) and 2-(3-(triethoxysilyl)propyl)-2H-tetrazol-5-amine (Compound 1b) (14.4 g, 49.8 mmol) obtained in Reference Example 1 was dissolved in dimethylformamide (25.0 mL), carbonyldiimidazole (4.04 g, 24.9 mmol) was added, and the mixture was heated at 60 °C for 18.5 hours with stirring. After distilling off the solvent under reduced pressure, the residue was dissolved in ethyl acetate (70 mL) and washed 5 times with water (70 mL). After drying the organic layer over anhydrous sodium sulfate, it was filtered and concentrated under reduced pressure to obtain a mixture of 1,3-bis(1-(3-(triethoxysilyl)propyl)-1H-tetrazol-5-yl)urea (Compound 2a), 1,3-bis(2-(3-(triethoxysilyl)propyl)-2H-tetrazol-5-yl)urea (Compound 2b), and 1-(1-(3-(triethoxysilyl)propyl)-1H-tetrazol-5-yl)-3-(2-(3-(triethoxysilyl)propyl)-2H-tetrazol-5-yl)urea (Compound 2c) (12.8 g, 17.6 mmol, yield 71%). 1 H-NMR (400 MHz, DMSO-d6) 10.4 (br, 2H), 4.62 - 4.02 (m, 4H), 3.77 - 3.68 (m, 12H), 1.99 - 1.71 (m, 4H), 1.17 - 1.09 (m, 18H), 0.59 - 0.48 (m, 4H) ESI-TOF-MS, m / z: [M+Na] + C 21 H 44 N 10 NaO7Si2 + Calculated value for 627.28; Measured value 627.26.

[0071]

Chemical Structure

[0072]

Chemical Structure

[0073] [ka]

[0074] Example 2: Adhesion Strength Test The adhesion between the bis(tetrazolyl)urea compound synthesized in Example 1 (a mixture of compounds 2a, 2b, and 2c) and the comparative example compound of Reference Example 1 (a mixture of compounds 1a and 1b) was evaluated according to the following method.

[0075] <2-1. Preparation of the test solution> To 10 g of the test compound (a mixture of compounds 2a, 2b, and 2c obtained in Example 1, or a mixture of compounds 1a and 1b obtained in Reference Example 1), 200 g of ethylene glycol monobutyl ether and 790 g of water were added, and the mixture was stirred at room temperature for 2 hours to prepare the test solution.

[0076] <2-2. Preparation of adhesion strength test specimens> (1) Substrate A An electroplated copper plate (25 μm thick) was applied to one arbitrary surface of a copper-clad laminate with carrier foil (referred to as substrate A) using a conventional method.

[0077] (2) Test solution treatment of substrate A The copper-plated surface of substrate A, which was copper-plated as described in (1) above, was treated with the test solution prepared in 2-1 above, according to the following procedure. i) The copper-plated surface of substrate A is acid-cleaned at room temperature for 1 minute, rinsed with water, and then dried at 100°C for 1 minute. ii) Immerse the substrate A after treatment i) in the test solution obtained in 2-1 above (at room temperature for 1 minute), rinse with water, and dry at 100°C for 1 minute.

[0078] (3) Bonding of substrate A to insulating film In (2) above, an interlayer insulating film (ABF-GL510 manufactured by Ajinomoto Fine Techno Co., Ltd.) was laminated onto substrate A, which had been treated with a surface treatment agent, using a vacuum laminator.

[0079] (4) Substrate B A separate copper-clad laminate (referred to as substrate B) was prepared, and an interlayer insulating film (ABF-GL510 manufactured by Ajinomoto Fine Techno Co., Ltd.) was laminated onto one arbitrary surface of the laminate using a vacuum laminator.

[0080] (5) Pressing substrate A and substrate B together Substrate A, which underwent the process described in (3) above, and substrate B, which was obtained in (4) above, were pressed together so that the interlayer insulating film surfaces were in contact with each other (pressure 3 MPa, temperature 190°C, time 90 minutes).

[0081] (6) Delamination of the carrier foil from substrate A From the laminate obtained by pressing in (5), the copper-clad laminate with carrier foil (substrate A) was peeled off at the carrier foil to obtain a copper-clad laminate in which an interlayer insulating film and a copper plating layer were laminated on one side surface of substrate B. This laminate was used for adhesion strength testing.

[0082] <2-3. Adhesion Strength Test> (1) High-speed accelerated life test (HAST) The copper-clad laminate obtained in 2-2.(6) above was subjected to unsaturated pressure cooker treatment. The test conditions were as follows: Test conditions: Temperature 130°C, relative humidity 85%RH, 100 hours

[0083] (2) Adhesion strength between the copper plating layer and the interlayer insulating film The laminate obtained in 2-2.(6), or the laminate after HAST, was cut to a width of 25 mm. A 10 mm wide incision was made on the cut laminate to create a test peel, and the peel strength (kgf / cm) of the interface between the copper plating layer and the interlayer insulating film of the test peel was measured according to JIS C 6481 (1996).

[0084] The adhesion strength between the copper plating layer and the interlayer insulating film before and after the high-speed accelerated life test is as shown in the table below.

[0085] [Table 1]

[0086] The compound of Example 1 has a dimer structure formed by condensing the compounds of Reference Example 1 via a carbonyl group. Therefore, if we compare the compound of Example 1 and the compound of Reference Example 1 in equimolar amounts, the compound of Example 1 has approximately twice the amount of trialkoxysilyl groups and imidazole rings. On the other hand, as described in 2-2 above, the test solution was prepared using the same mass of the compounds of Reference Example 1 and Example 1. Therefore, in the test solution used in the adhesion test, the amount of Example 1 contained in the test solution was approximately half the amount of Reference Example 1 in molar ratio. In that case, the amount of tetrazole rings and alkoxysilyl groups contained in the test solution would be approximately the same for both Example 1 and Reference Example 1, so it would be expected that the adhesion strength would be similar. However, when the adhesion test was actually performed, it was found that Example 1 had stronger adhesion strength than Reference Example 1. Furthermore, after HAST, the adhesion strength of the compound of Example 1 was approximately twice that of the compound of Reference Example 1.

[0087] From these results, it can be seen that the compound in this embodiment exhibits high adhesion between metal and resin materials, and in particular, the adhesion strength is improved after high-speed accelerated life testing.

Claims

1. General formula (I) 【Chemistry 1】 (In the formula, R is independently -(CH 2 ) n -Si(Y) 3 (This represents n, where n independently represents an integer from 1 to 6, and Y independently represents an alkoxy group.) The compound shown by [this symbol].

2. The compound according to claim 1, wherein Y is a methoxy group or an ethoxy group, and n is 3 or 4.

3. A silane coupling agent containing the compound described in claim 1.

4. A silane coupling agent according to claim 3, used for bonding two materials selected from metals, inorganic materials, and resin materials.

5. A silane coupling agent according to claim 3, used for bonding metal and resin materials.

6. The silane coupling agent according to claim 5, wherein the metal is at least one selected from copper, aluminum, titanium, nickel, tin, iron, silver, gold, and alloys thereof.

7. The silane coupling agent according to claim 5, wherein the metal is copper or a copper alloy.

8. The silane coupling agent according to any one of claims 4 to 7, wherein the resin material is at least one selected from acrylic resin, epoxy resin, olefin resin, polybenzoxazole resin, silicone resin, polyimide resin, phenolic resin, and bismaleimide resin.

9. A surface treatment agent containing the compound described in claim 1.

10. A surface treatment agent according to claim 9, used for bonding two materials selected from metals, inorganic materials, and resin materials.

11. A surface treatment agent according to claim 9, used for bonding metal and resin materials.

12. The surface treatment agent according to claim 11, wherein the metal is at least one selected from copper, aluminum, titanium, nickel, tin, iron, silver, gold, and alloys thereof.

13. The surface treatment agent according to claim 11, wherein the metal is copper or a copper alloy.

14. The surface treatment agent according to any one of claims 10 to 13, wherein the resin material is at least one selected from acrylic resin, epoxy resin, olefin resin, polybenzoxazole resin, silicone resin, polyimide resin, phenolic resin, and bismaleimide resin.

Images