Surface treatment agent and surface treatment method for electronic grade glass fiber cloth used in IC carrier board

Abstract

The present invention provides a surface treatment method for an electronic grade glass fiber cloth for an IC carrier board, comprising the following steps: Step (1), after the electronic grade glass fiber cloth is woven, it is first subjected to a primary heat desizing and cleaning, and then subjected to a secondary heat desizing treatment for a long time; Step (2), the desized electronic grade glass fiber cloth after two desizing processes is sent, and the pretreatment process is carried out by soaking in an impregnation tank containing a pretreatment liquid of a silane coupling agent, and then taken out and dried; Step (3), then it enters an impregnation tank containing a silane coupling agent treatment agent for soaking treatment, and then taken out and successively dried, washed with water, dried, and wound up. The glass cloth treated with the surface treatment agent for the electronic grade glass fiber cloth provided by the present invention has better impregnability, heat resistance, tensile strength, and coefficient of thermal expansion, can meet the use requirements of the IC carrier board, can fully improve the market competitiveness, and seize the market opportunity.

Description

Technical Field

[0001] The present invention relates to the technical field of surface treatment of electronic glass fiber cloth, and particularly relates to a surface treatment agent for electronic glass fiber cloth for IC substrates and a surface treatment method thereof. Background Art

[0002] IC substrates have the characteristics of high density, high precision, high performance, miniaturization, and thinness. IC substrates are developed on the basis of HDI boards and are technological innovations that adapt to the rapid development of electronic packaging technology, with characteristics such as high density, high precision, high performance, miniaturization, and thinness. Encapsulation substrates are a key special basic material used in advanced packaging, playing a role in electrical conduction between IC chips and conventional PCBs. At the same time, they provide protection, support, heat dissipation for the chips, and form standardized mounting dimensions. The downstream applications of IC packaging substrates are extensive, mainly used in consumer electronics, communication equipment, industrial control, medical, and other fields. According to disclosures by research institutions, in the market development of packaging substrates in China, the domestic chip packaging and testing foundry currently accounts for more than 20% of the global share, but the operating income of China's IC substrates accounts for less than 4% of the global market. In the long run, there is still a large domestic substitution space in the domestic packaging substrate industry. In terms of the industry development prospect, the overall development situation of the industry is clear, and the potential for domestic substitution is great. Technically speaking, encapsulation substrates are developed on the basis of HDI boards and are an extension to high-end technologies that adapt to the rapid development of electronic packaging technology. Therefore, developing a surface treatment agent for electronic glass fiber cloth for IC substrates has important practical significance and is conducive to quickly seizing the market. In addition, IC substrates have a lower coefficient of thermal expansion and higher strength compared to ordinary PCB boards.

[0003] The principle of the surface treatment of glass fiber cloth by the surface treatment agent for electronic glass fiber cloth is generally considered that the silane hydrolysis solution obtained after silane hydrolysis contains many silanol structures, which can undergo dehydration condensation with the silanols on the surface of the glass cloth to form stable si-o-si chemical bonds. The organic functional groups at the other end of the silane structure, such as amino groups and vinyl groups, can form stable chemical bonds with the organic functional groups on the resin. The silane surface treatment agent is the intermediate bridge for the combination of the glass cloth and the resin and plays a very important role.

[0004] The currently commonly used surface treatment agent for fiberglass cloth is amino silane, which can match the FR-4 resin system commonly used downstream. However, due to the characteristics of the FR-4 resin itself, the thermal expansion coefficient of the board after combination with fiberglass cloth is relatively high, that is, the board shrinks greatly when heated, making it difficult to meet the requirements of miniaturization, thinness and lightness of IC substrates. Therefore, the resin system must be replaced. For example, BT resin and the compound resin system with BT resin as the main resin are the current research mainstream, and the commonly used one is the BT modified resin system. Therefore, the simple amino silane surface treatment agent can no longer meet the usage requirements. In addition, considering the strength requirements of the fiberglass cloth for IC substrates, it is necessary to develop a new type of surface treatment agent for fiberglass cloth used in IC substrates. Summary of the Invention

[0005] In order to solve the above technical problems in the prior art, the present invention provides a surface treatment agent for electronic-grade fiberglass cloth used in IC substrates and its treatment method, so that it can be well matched and combined with the resin (BT modified resin) for IC substrates downstream, making the produced electronic-grade fiberglass cloth have high strength and low thermal expansion coefficient, meeting the performance requirements of IC substrates.

[0006] To achieve the above object, the present invention adopts the following technical solutions:

[0007] The present invention provides a surface treatment agent for electronic-grade fiberglass cloth used in IC substrates, including a silane coupling agent pretreatment solution and a silane coupling agent treatment agent. Among them, the silane coupling agent pretreatment solution includes the following components by weight percentage:

[0008] Silane A: Epoxy group silane with the general formula (CH2OCHR1Si(OCH3)3) 0.25% - 0.6%, where R1 is an alkyl group with 3 - 5 carbon atoms;

[0009] pH regulator: Glacial acetic acid 0.05% - 0.8%;

[0010] Low-foaming surfactant: Polyether-modified organosilicon 0.01% - 0.03%;

[0011] Dispersant: Absolute ethanol 0.25% - 0.6%;

[0012] Pure water: The balance is pure water.

[0013] The silane coupling agent treatment agent includes the following components by weight percentage:

[0014] Silane B: Amino silane with the general formula (C6H5NHR2Si(OCH3)3) 0.3% - 0.5%, where R2 is an alkyl group with 4 - 6 carbon atoms;

[0015] Silane C: Vinyl silane has a general formula of (C6H5CH=CHR3Si(OCH3)3) with a content of 0.2% to 0.4%, where R3 is an alkyl group with 3 to 5 carbon atoms;

[0016] pH regulator: Glacial acetic acid 0.1% - 0.8%;

[0017] Low-foaming surfactant: Polyether-modified silicone 0.02% - 0.04%;

[0018] Dispersant: Absolute ethanol 0.4% - 0.8%;

[0019] Pure water: The balance is pure water.

[0020] The present invention also provides a surface treatment method for an electronic-grade glass fiber cloth for an IC carrier board, including the following steps:

[0021] Step (1), after the electronic-grade glass fiber cloth is woven, it is first subjected to a primary heat desizing and cleaning, and then a long-time secondary heat desizing treatment;

[0022] Step (2), the desized electronic-grade glass fiber cloth after two desizing processes is sent for pretreatment. The pretreatment process is to soak it with a silane coupling agent pretreatment solution, and then take it out and dry it;

[0023] Step (3), the electronic-grade glass fiber cloth treated in step (2) is soaked with a silane coupling agent treatment agent, and after taking it out, it is dried, washed with water, dried, and wound up in sequence.

[0024] Furthermore, the preparation method of the silane coupling agent pretreatment solution includes the following steps:

[0025] Step (1), first weigh a certain amount of silane A stock solution and absolute ethanol and mix them, and then slowly drop glacial acetic acid for pre-acidification treatment, and stir and mix evenly to obtain a silane A pre-acidified solution;

[0026] Step (2), clean the on-site foaming material A barrel, and then add pure water and glacial acetic acid and mix and stir;

[0027] Step (3), add a low-foaming surfactant to the solution mixed in step (2) and mix and stir;

[0028] Step (4), drop the silane A pre-acidified solution in step (1) into the solution mixed in step (3) through a dropping funnel, and mix and stir to obtain the silane coupling agent pretreatment solution.

[0029] Furthermore, the preparation method of the silane coupling agent treatment agent includes the following steps:

[0030] Step (1): Weigh a certain amount of silane C stock solution and absolute ethanol first, and then slowly add glacial acetic acid dropwise for pre-acidification treatment respectively. Stir and mix evenly to obtain a pre-acidified silane C solution.

[0031] Step (2): Clean the on-site foaming material B barrel, and then add pure water and glacial acetic acid for mixing and stirring.

[0032] Step (3): Add a low-foaming surfactant to the solution mixed in step (2) for mixing and stirring, and then add silane B stock solution dropwise with a dropping funnel for mixing and stirring.

[0033] Step (4): Add the pre-acidified silane C solution in step (1) dropwise to the solution mixed in step (3), and stir and mix to obtain a silane coupling agent treatment agent.

[0034] Further, in the above step (1), the addition amount of glacial acetic acid is 0.02 wt% of the total mass of the silane stock solution. Further, in the above step (1), the pH value of the pre-acidification treatment is 2.0 - 4.0.

[0035] Further, in the above step (2), the addition amount of pure water is 400 - 1000 L, and the addition amount of glacial acetic acid is 1 - 8 L.

[0036] Further, in the above step (2) or step (3), the stirring time is ≥10 min; in the above step (4), the stirring time is 30 min.

[0037] Further, in the above steps (1) - (3), the stirring frequency is 50 - 70 Hz; in the above step (4), the stirring frequency is 5 - 10 Hz.

[0038] The present invention adopts the above technical solutions, and compared with the prior art, has the following technical effects:

[0039] 1. In the present invention, the low-foaming surfactant used is polyether-modified silicone, such as the CX-30B surfactant of Wuhan Meixin Meili New Materials. It is soluble in organic solvents and has excellent wetting performance. It can significantly reduce the surface tension of the treatment liquid. By reducing the surface tension, the surfactant can make various components in the treatment liquid miscible with each other, promote hydrolysis, especially for oily silane A and silane B. In addition, it can also make the treatment liquid quickly penetrate between fiberglass cloths, especially between single fiberglass yarns, which is beneficial to the full impregnation treatment of the fiberglass cloth by the silane treatment liquid, thereby improving the impregnation of the fiberglass cloth. This sizing agent is highly efficient in small amounts, and the addition amount can be as low as 100 ppm. It can significantly reduce the surface tension and has chemical inertness, that is, it will not react with silane and downstream resins. Most importantly, this surfactant also has the characteristic of low foaming, which can significantly reduce the possibility of treatment liquid polymerization.

[0040] 2. In the present invention, the dispersant is anhydrous ethanol, which has excellent water solubility and low cost. In the present invention, vinyl silanes and epoxy silanes are both oily and more difficult to hydrolyze than amino silanes. Therefore, it is necessary to dilute and disperse them before hydrolysis.

[0041] 3. In the present invention, silane A is an epoxy silane, which does not contain amino, vinyl, and benzene rings. Epoxy silanes can react and combine with acrylic and styrene resins. The BT modified resin has a complex composition and contains a small amount of acrylic and styrene resins. Therefore, silane A is used as an auxiliary silane coupling agent and is used separately from amino silane B to prevent the two from undergoing a polymerization reaction; silane B and silane C are amino silane and vinyl silane respectively, both containing benzene rings. The benzene ring can enhance the rigidity of the silane structure, thereby improving the strength of the glass fiber cloth.

[0042] 4. The surface treatment agent of the electronic grade glass fiber cloth of the present invention corresponds to the BT modified resin system compared to the traditional treatment agent corresponding to the epoxy resin system. It can be well matched and combined with the downstream resin for IC carrier board (BT modified resin), making the produced electronic grade glass fiber cloth have high strength and low coefficient of thermal expansion, meeting the performance requirements of the IC carrier board.

[0043] 5. The glass cloth treated with the surface treatment agent of the electronic grade glass fiber cloth provided by the present invention has better impregnability, heat resistance, tensile strength, and coefficient of thermal expansion, can meet the use requirements of the IC carrier board, can fully improve the market competitiveness, and seize the market opportunity. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1 It is a process flow chart for the surface treatment of the electronic grade glass fiber cloth for IC carrier board. DETAILED DESCRIPTION OF THE INVENTION

[0045] The following specific examples further illustrate the present invention, but do not limit the present invention. It should be noted that, without conflict, the embodiments in the present invention and the features in the embodiments can be combined with each other.

[0046] Example 1

[0047] This example provides a surface treatment method for the electronic grade glass fiber cloth for IC carrier board, including the following steps:

[0048] Step (1): After the electronic grade glass fiber cloth is woven, it is first subjected to a primary heat desizing and cleaning, and then subjected to a secondary heat desizing treatment for a long time.

[0049] Step (2): The desized electronic-grade fiberglass cloth after two desizing processes is sent for treatment. The pretreatment process is carried out by soaking in an impregnation tank containing a pretreatment solution of silane coupling agent, and then taken out and dried;

[0050] Step (3): Then it enters an impregnation tank containing a silane coupling agent treatment agent for soaking treatment, and then taken out and successively dried, washed with water, dried again, and wound up;

[0051] Among them, in the said step (2), the formulation of the silane coupling agent pretreatment solution is shown in Table 1 below:

[0052] Table 1

[0053]

[0054] In the said step (3), the formulation of the silane coupling agent treatment agent is shown in Table 2 below:

[0055] Table 2

[0056]

[0057]

[0058] This embodiment also provides a preparation method for the above-mentioned silane coupling agent pretreatment solution and silane coupling agent treatment agent, including the following steps:

[0059] Step (1): First, weigh a certain amount of silane A stock solution and silane C stock solution, add an equal amount of absolute ethanol to silane A and silane C respectively, and then slowly drop 0.02% of the mass percentage of the silane stock solution of glacial acetic acid for pre-acidification treatment. The pH value of the pre-acidification treatment is 2.0 - 4.0, and stir and mix evenly for standby;

[0060] Step (2): Clean the on-site material bucket A, add 400 - 1000 L of pure water, turn on the stirring equipment, set the stirring frequency to 50 - 70 Hz, add 1 - 8 L of glacial acetic acid, stir for at least 10 min, then add a low-foaming surfactant, stir for at least 10 min, and then use a dropping funnel to drop the pre-acidified solution of silane A prepared in step (1). Finally, stir for at least 30 min to obtain a clear and transparent solution (silane coupling agent pretreatment solution), and adjust the stirring frequency to 5 - 10 Hz, then it can be used for feeding;

[0061] Step (3): Clean the on-site B barrel for foaming materials, add 400 - 1000 L of pure water, turn on the stirring equipment, set the stirring frequency to 50 - 70 Hz, add 1 - 8 L of glacial acetic acid, stir for at least 10 min, then add a low-foaming surfactant, stir for at least 10 min, and then add the original solution of silane B dropwise with a dropping funnel. After the dropping is completed, stir for another 10 min, then add the original solution of silane C prepared in step (1). Finally, stir for 30 min to obtain a clear and transparent solution (silane coupling agent treatment agent). Adjust the stirring frequency to 5 - 10 Hz, and then it can be used for feeding materials.

[0062] Comparative Example 1:

[0063] The surface treatment method for the electronic grade glass fiber cloth used in the IC carrier board provided in this comparative example includes the following steps:

[0064] Step (1): After the electronic grade glass fiber cloth is woven, it is first subjected to a primary heat desizing and cleaning, and then a long-term secondary heat desizing treatment.

[0065] Step (2): The desized electronic grade glass fiber cloth after two desizing processes is sent for treatment. The treatment process is carried out by soaking in an impregnating tank containing an amino group-containing silane surface treatment agent, and then taken out and dried, washed with water, dried, and wound up in sequence.

[0066] This comparative example uses a single amino group-containing silane surface treatment agent, and its formulation composition is shown in Table 3 below:

[0067] Table 3

[0068] Name Mass (kg) Pure water 1000 Glacial acetic acid 5 Silane B 7

[0069] The preparation method of the surface treatment agent in this comparative example is similar to that of Example 1.

[0070] Comparative Example 2:

[0071] The surface treatment method for the electronic grade glass fiber cloth used in the IC carrier board provided in this comparative example includes the following steps:

[0072] Step (1): After the electronic grade glass fiber cloth is woven, it is first subjected to a primary heat desizing and cleaning, and then a long-term secondary heat desizing treatment.

[0073] Step (2): The desized electronic grade glass fiber cloth after two desizing processes is sent for treatment. The treatment process is carried out by soaking in an impregnating tank containing a surface treatment agent, and then taken out and dried, washed with water, dried, and wound up in sequence.

[0074] The surface treatment agent for the electronic grade glass fiber cloth used in the IC carrier board in this comparative example, its formulation composition is shown in Table 4 below:

[0075] Table 4

[0076] Name Mass (kg) Pure water 1000 Glacial acetic acid 6 Dispersant 8 Low-foaming surfactant 0.4 Silane B 5 Silane C 4

[0077] The preparation method of the surface treatment agent in this comparative example is similar to that in Example 1 of the present invention.

[0078] Application example:

[0079] (1) The physical properties of the electronic-grade glass fiber cloth impregnated with the corresponding treatment solutions in the above-mentioned examples and comparative examples were compared and tested. The specific test results are shown in Table 5 below:

[0080] Table 5

[0081]

[0082] It can be seen from the data in the above table that the impregnability of 1037 and 2116 impregnated with the treatment solutions corresponding to Example 1 is significantly better than that of Comparative Examples 1-2, and the tensile strength is also better. The impregnability and tensile strength of Comparative Example 1 are the worst.

[0083] (2) The heat resistance test results of the PP boards obtained by downstream treatment of the glass cloth treated with the corresponding treatment agents in Example 1 and Comparative Examples 1-2 of the above are shown in Table 6 below:

[0084] Table 6

[0085]

[0086] It can be seen from the test data in the above table that the board obtained by downstream treatment of the glass cloth treated with the treatment agent corresponding to Example 1 has better heat resistance. On the one hand, due to the impregnation treatment of the glass fiber cloth with the pretreatment solution of the silane coupling agent and the silane coupling agent treatment agent, there are more silanol groups on the cloth surface. Coupled with the better impregnability of the glass fiber cloth, there are richer organic functional groups that can be combined with the downstream resin. Therefore, it is more tightly combined with the downstream resin, and thus has good heat resistance.

[0087] (3) The CTE test was carried out on the substrates obtained by downstream treatment of the glass cloth treated with the corresponding treatment agents in Example 1 and Comparative Examples 1-2 of the above. The test results are shown in Table 7 below:

[0088] Table 7

[0089]

[0090] It can be seen from the test data in the above table that Example 1 has a lower coefficient of thermal expansion (CTE), meeting the usage requirements of IC substrates.

[0091] In summary, the glass cloth treated with the surface treatment agent for electronic-grade glass fiber cloth provided by the present invention has better impregnability, heat resistance, tensile strength, and coefficient of thermal expansion, can meet the usage requirements of IC substrates, can fully improve the market competitiveness, and seize the market opportunity.

[0092] The specific embodiments of the present invention have been described in detail above, but they are only examples, and the present invention is not limited to the specific embodiments described above. For those skilled in the art, any equivalent modifications and substitutions made to this utility are also within the scope of the present invention. Therefore, all equivalent transformations and modifications made without departing from the spirit and scope of the present invention should be covered within the scope of the present invention.

Claims

1. A surface treatment agent for electronic grade glass fiber cloth used in IC substrates, characterized in that, It includes a silane coupling agent pretreatment solution and a silane coupling agent treatment agent. Among them, the silane coupling agent pretreatment solution includes the following components by weight percentage: Silane A: CH2OCHR1Si(OCH3)3, where R1 is an alkyl group with 3 to 5 carbon atoms, 0.25% - 0.6%; pH regulator: glacial acetic acid 0.05% - 0.8%; Low-foaming surfactant: polyether-modified silicone 0.01% - 0.03%; Dispersant: absolute ethanol 0.25% - 0.6%; Purified water: the balance is purified water; The silane coupling agent treatment agent includes the following components by weight percentage: Silane B: C6H5NHR2Si(OCH3)3, where R2 is an alkyl group with 4 to 6 carbon atoms, 0.3% - 0.5%; Silane C: C6H5CH=CHR3Si(OCH3)3, where R3 is an alkyl group with 3 to 5 carbon atoms, 0.2% - 0.4%; pH regulator: glacial acetic acid 0.1% - 0.8%; Low-foaming surfactant: polyether-modified silicone 0.02% - 0.04%; Dispersant: absolute ethanol 0.4% - 0.8%; Purified water: the balance is purified water.

2. A surface treatment method for an electronic grade glass fiber cloth for an IC carrier board using the surface treatment agent for the electronic grade glass fiber cloth for an IC carrier board described in claim 1, characterized in that, It includes the following steps: Step (1): After the electronic-grade fiberglass cloth is woven, it is first subjected to a primary heat desizing and cleaning, and then a secondary heat desizing treatment for a long time; Step (2): The desized electronic-grade fiberglass cloth after two desizing processes is sent for pretreatment. The pretreatment process is to soak it with the silane coupling agent pretreatment solution, and then take it out and dry it; Step (3): The electronic-grade fiberglass cloth treated in step (2) is soaked with the silane coupling agent treatment agent, taken out, and then dried, washed with water, dried again, and wound up in sequence.

3. The method according to claim 2, wherein The preparation method of the silane coupling agent pretreatment solution includes the following steps: Step (1): First, weigh a certain amount of silane A stock solution and absolute ethanol and mix them, and then slowly add glacial acetic acid for pre-acidification treatment, and stir and mix evenly to obtain a silane A pre-acidified solution; Step (2): Clean the on-site charging barrel A, and then add purified water and glacial acetic acid and mix and stir; Step (3): Add a low-foaming surfactant to the solution mixed in step (2) and mix and stir; Step (4): Drop the silane A pre-acidified solution in step (1) into the solution mixed in step (3) through a dropping funnel, and mix and stir to obtain the silane coupling agent pretreatment solution.

4. The method according to claim 2, characterized in that The preparation method of the silane coupling agent treatment agent includes the following steps: Step (1): First, weigh a certain amount of silane C stock solution and absolute ethanol, and then slowly add glacial acetic acid for pre-acidification treatment respectively, and stir and mix evenly to obtain a silane C pre-acidified solution; Step (2): Clean the on-site charging barrel B, and then add purified water and glacial acetic acid and mix and stir; Step (3): Add a low-foaming surfactant to the solution mixed in step (2) and mix and stir, and then drop the silane B stock solution through a dropping funnel and mix and stir; Step (4): Drop the silane C pre-acidified solution in step (1) into the solution mixed in step (3), and mix and stir to obtain the silane coupling agent treatment agent.

5. The method according to claim 3 or 4, characterized in that, In the step (1), the addition amount of glacial acetic acid is 0.02 wt% of the total mass of the silane stock solution.

6. The method according to claim 3 or 4, characterized in that In the step (1), the pH value of the pre-acidification treatment is 2.0 - 4.

0.

7. The method according to claim 3 or 4, characterized in that, In the step (2), the addition amount of pure water is 400 - 1000 L, and the addition amount of glacial acetic acid is 1 - 8 L.

8. The method according to claim 3 or 4, characterized in that, In the step (2) or step (3), the stirring time is ≥10 min; in the step (4), the stirring time is 30 min.

9. The method according to claim 3 or 4, characterized in that, In the steps (1) - (3), the stirring frequency is 50 - 70 Hz; in the step (4), the stirring frequency is 5 - 10 Hz.

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