CN115011295A

CN115011295A - Halogen-free adhesive for manufacturing copper clad laminate and preparation method thereof

Info

Publication number: CN115011295A
Application number: CN202210761436.7A
Authority: CN
Inventors: 况小军; 叶志; 吴兴游
Original assignee: Jiangxi Hongruixing Technology Co ltd
Current assignee: Jiangxi Hongruixing Technology Co ltd
Priority date: 2022-06-29
Filing date: 2022-06-29
Publication date: 2022-09-06

Abstract

The invention discloses a halogen-free adhesive for manufacturing a copper-clad laminate, which is characterized in that the adhesive comprises the following components in percentage by weight of solid (without solvent) in the total weight of solid of a composition: 25% -40% of basic epoxy resin; 8 to 20 percent of phenolic epoxy resin; 0.5 to 3 percent of four-functional group epoxy resin; 15% -30% of a phosphorus-containing curing agent; dicyandiamide 0.5% -3%; 1% -5% of a toughening agent; 2 to 10 percent of flame retardant; 0.05 to 1.00 percent of epoxy resin curing accelerator; 20 to 45 percent of inorganic filler. The invention also discloses a preparation method of the composition. The copper-clad plate prepared by the method has good high heat resistance, and good PCB processability and excellent anti-stripping strength. Is completely suitable for the PCB industry to be applied to halogen-free lead-free manufacture procedure and manufacture and processing of multilayer boards.

Description

Halogen-free adhesive for manufacturing copper-clad laminate and preparation method thereof

Technical Field

The invention belongs to the technical field of new materials, and relates to a halogen-free adhesive for manufacturing a copper-clad laminate and a preparation method thereof.

Background

Most of materials in the market at present are halogen flame retardant, and the halogen-containing epoxy resin is generally applied industrially to achieve the purpose of flame retardant of the materials. In particular, epoxy resins containing bromine are most widely used. The mechanism of flame retardance is as follows. It is thermally decomposed to generate hydrogen halide during combustion, and the free radicals generated during the thermal decomposition of the polymer during combustion are consumed by the hydrogen halide, so that the chain reaction is delayed or interrupted during combustion. The hydrogen halide gas is a flame retardant gas, and has a higher density than air, and forms a barrier on the surface of the polymer material, thereby reducing the combustibility of the polymer material. Therefore, the halogen-containing epoxy resin has high flame retardancy.

It has been reported in the literature that while bromine-containing halides have excellent flame retardancy, toxic chlorine is generated during combustion. Since halogen-containing substances can generate carcinogenic dioxins, the use of the molding device is extremely strictly controlled. Therefore, the industry demands the use of non-halogen flame retardant type flame retardant, namely the use of halogen-free flame retardant type printed circuit substrates, and the molded products are required to be used in the processes of detection, PCB processing and application, appliance fire, disposal (including recycling, burying, burning) and the like, and the molded products do not generate substances harmful to human and environment.

Now, the industry has developed the non-halogen flame retardant blended in the common epoxy resin, but the flame retardant materials have the following problems in application, namely the high heat resistance of the composition material is poor or the brittleness is relatively high, the peeling strength is relatively low, and the like.

Disclosure of Invention

In view of the above problems, an object of the present invention is to provide a halogen-free adhesive for producing a copper clad laminate and a method for producing the same.

The copper clad laminate is a flame-retardant epoxy glass cloth-based copper clad laminate.

The manufactured copper-clad plate has good high heat resistance, and good PCB processability and excellent anti-stripping strength.

In order to realize the purpose of the invention, the adopted technical scheme is as follows:

the halogen-free adhesive for manufacturing the copper clad laminate comprises the following components in percentage by weight of solid (without solvent) in the total solid weight of the composition:

in a preferred embodiment of the present invention, the physical property requirement of the base epoxy resin is that the epoxy equivalent EEW (g/eq) is between 160-210;

hydrolysable chlorine (dipropylene glycol methyl ether) was 300 MAX. BE188 resin from Taiwan Changchun chemical company is preferred.

In a preferred embodiment of the present invention, the novolac epoxy resin is any one or more of bisphenol a novolac epoxy resin, bisphenol F novolac epoxy resin, or o-cresol novolac epoxy resin. BNE200 resin from Changchun chemical company of Taiwan is preferred.

In a preferred embodiment of the present invention, the epoxy equivalent weight of the tetrafunctional epoxy resin is between 180-220;

the weight percentage of the tetrafunctional group resin is preferably 0.5-2.5%.

In a preferred embodiment of the present invention, the resin physical property requirement of the phosphorus-containing curing agent is that the hydroxyl equivalent (g/eq) is between 330 and 560;

hydrolyzable chlorine (dipropylene glycol methyl ether) 300 MAX;

the phosphorus content (wt%) is 8-10;

the solid content (wt%) is 54-60.

In a preferred embodiment of the present invention, the phosphorus-containing curing agent is a bisphenol a-type phosphorus-containing phenolic resin prepared by reacting a phosphorus-containing compound with a bisphenol a-type epoxy resin. A Dow chemically produced resin, trade name XZ-92741 is preferred, but not limited thereto.

In a preferred embodiment of the invention, the toughening agent is a nano-scale core-shell rubber, and the nano range is 50-100 nm. Preferably, but not limited to, STR-8330, a Loyang Chart.

In a preferred embodiment of the present invention, the flame retardant is a phosphorus-containing flame retardant. PX-200 of Dai eight Chemicals, Japan, is preferred, but not limited thereto.

In a preferred embodiment of the present invention, the epoxy resin curing accelerator is a curing accelerator for accelerating the curing of the epoxy resin, and is any one or more of 2-ethyl-4-methylimidazole and 1-benzyl-2-methylimidazole. 2-ethyl-4-methylimidazole is preferred.

In a preferred embodiment of the present invention, the inorganic filler is any one or more of talc, quartz powder, ceramic powder, aluminum hydroxide, or metal oxide particles. The metal oxide particles are any one or more of silicon dioxide, clay and boron nitride.

The halogen-free adhesive for manufacturing the copper clad laminate further comprises an organic solvent, wherein the organic solvent enables the solid content of the halogen-free adhesive to be 52% or more, and the organic solvent is any one or more of acetone, methyl ethyl ketone, toluene, xylene, methyl isobutyl ketone, propylene glycol methyl ether and cyclohexanone. The preferable dosage is 55-75%.

Such a preferable amount is selected from the synergistic effect of ease of impregnation of the epoxy resin binder into the matrix in the case of preparing the prepreg and good adhesion between the resin composition and the matrix.

A preparation method of a halogen-free adhesive for manufacturing a copper clad laminate comprises the following steps:

firstly, stirring the part of the organic solvent, the dicyandiamide, the flexibilizer and the fire retardant for 30-80 minutes at the rotating speed of 800-1600 rpm and the temperature of 20-45 ℃ until the dicyandiamide is completely dissolved;

secondly, adding inorganic filler into the product obtained in the first step and stirring for 30-60 minutes;

thirdly, adding the basic epoxy resin, the four-functional group epoxy resin, the phosphorus-containing curing agent and the novolac epoxy resin into the product obtained in the second step, and shearing and emulsifying the mixture for 2 to 4 hours at the rotating speed of 1200-1500 rpm and the temperature of 20 to 45 DEG C

And fourthly, adding the organic solvent into the epoxy resin curing accelerator until the organic solvent is completely dissolved, adding the epoxy resin curing accelerator into the product obtained in the third step, and discharging the epoxy resin curing accelerator for 4 to 12 hours at the rotation speed of 1200-1500 rpm to obtain the halogen-free adhesive.

The invention has the beneficial effects that:

the manufactured copper-clad plate has good high heat resistance, and good PCB processability and excellent anti-stripping strength. Is completely suitable for the PCB industry to be applied to halogen-free lead-free manufacture procedure and manufacture and processing of multilayer boards.

Detailed Description

The present invention will be described below with reference to specific examples, and the characteristics of the laminates of examples 1 to 4 and comparative examples 1 to 2 were measured by the following method (see IPC-TM-650).

The basic epoxy resin in the embodiment is specifically BE188 resin of Changchun chemical industry, Taiwan, China.

The novolac epoxy resin is BNE200 resin of Changchun chemical company of Taiwan China.

The tetrafunctional group epoxy resin is vinpocetine TNE190 resin.

The phosphorus-containing curing agent is specifically XZ-92741 in the Dow chemical industry. Or also known as a phosphorus containing phenolic curing agent, DOW 92741 or SST-92741.

The toughening agent is specifically STR-8330 of a Luoyangsai chart, and is specifically core-shell rubber in a range of 50-100 nanometers.

The flame retardant is specifically PX-200 of Dai eight Chemicals, Japan.

The epoxy resin curing accelerator is specifically 2-ethyl-4-methylimidazole.

The inorganic filler is specifically aluminum hydroxide and silica.

The organic solvent is propylene glycol methyl ether.

(1) Glass transition temperature (Tg)

The glass transition temperature is the temperature (DEG C) at which the sheet changes from a glassy state to a highly elastic state (rubbery state) when heated.

The detection method comprises the following steps: by Differential Scanning Calorimetry (DSC)

(2) Thermal stratification time (T-288)

The T-288 thermal delamination time is the time that the sheet material is delaminated due to the action of heat at a set temperature of 288 ℃, and the time is kept before.

The detection method comprises the following steps: thermomechanical analysis (TMA) was used.

(3) Solder heat resistance

Solder heat resistance refers to the duration of time during which the sheet is immersed in molten solder at 288 ℃ without delamination and blistering.

The detection method comprises the following steps: cutting the etched substrate into 5.0cm × 5.0cm, sequentially polishing the plate edges with 120-mesh and 800-mesh abrasive paper, cooking for a certain time with a pressure cooker, placing in a tin melting furnace at 288 ℃, and observing whether delamination occurs or not.

(4) Peel strength

The test was carried out according to the IPC-TM-650-2.4.8C method.

(5) Flame resistance

The surface copper foil was etched away and sample preparation and testing was performed according to the flammability test of UL94 laminates.

Example 1

1. The compounding formulation proportions (in parts by weight solids) are shown in table 1 below:

TABLE 1

Raw material	Formulation ratio
		Basic epoxy resin	32
Novolac epoxy resin	10
		Tetrafunctional epoxy resin	1.5
Phosphorus-containing curing agent	20
		Dicyandiamide	1
Toughening agent	2.2
		Flame retardant	4
Inorganic filler	30
		Epoxy resin curing accelerator	0.09

2. Gluing and baking:

sizing speed of prepreg: 15 m/min;

3. prepreg control parameters:

gel time: 100 seconds;

resin content: 45 percent;

resin fluidity: 19 percent;

volatile components: 0.30 percent.

4. Parameters of the pressing plate:

vacuum degree: -0.088 MPa;

pressure: 120-500 psi;

temperature of the hot plate: 100 ℃ and 220 ℃;

curing time: >190 ℃ for 50 minutes.

5. The substrate performance parameters are shown in table 2:

TABLE 2

Example 2

1. The compounding formulation proportions (in parts by weight of solids) are shown in table 3 below:

TABLE 3

Raw material	Formulation ratio
		Basic epoxy resin	28
Novolac epoxy resin	13
		Tetrafunctional epoxy resin	1.6
Phosphorus-containing curing agent	18
		Dicyandiamide	1.2
Toughening agent	3.5
		Flame retardant	6
Inorganic filler	38
		Epoxy resin curing accelerator	0.11

2. Gluing and baking:

sizing speed of prepreg: 16 m/min'

3. Prepreg control parameters:

gel time: 110 seconds;

resin content: 44%;

resin fluidity: 18 percent;

volatile components: 0.30 percent;

4. parameters of the pressing plate:

vacuum degree: -0.088 MPa;

pressure: 120-500 psi;

temperature of the hot plate: 100 ℃ and 220 ℃;

curing time: >190 ℃ for 50 minutes.

5. The substrate performance parameters are shown in table 4 below:

TABLE 4

Example 3

1. The compounding formulation proportions (in parts by weight solids) are shown in table 5 below:

TABLE 5

Raw material	Formulation ratio
		Basic epoxy resin	36
Novolac epoxy resin	8
		Tetrafunctional epoxy resin	1.7
Phosphorus-containing curing agent	23
		Dicyandiamide	0.9
Toughening agent	1.5
		Flame retardant	5
Inorganic filler	41
		Epoxy resin curing accelerator	0.11

2. Gluing and baking:

sizing speed of prepreg: 18 m/min;

3. prepreg control parameters:

gel time: 95 seconds;

resin content: 43 percent;

resin fluidity: 16 percent;

volatile components: 0.30 percent;

4. parameters of the pressing plate:

vacuum degree: -0.088 MPa;

pressure: 120-500 psi;

temperature of the hot plate: 100 ℃ and 220 ℃;

curing time: >190 ℃ for 50 minutes.

5. The substrate performance parameters are as follows in table 6:

TABLE 6

Example 4

1. The compounding formulation proportions (in parts by weight of solids) are shown in table 7:

TABLE 7

Raw material	Formulation ratio
		Basic epoxy resin	26
Novolac epoxy resin	16
		Tetrafunctional epoxy resin	1.3
Phosphorus-containing curing agent	26
		Dicyandiamide	0.7
Toughening agent	4
		Flame retardant	3
Inorganic filler	27
		Epoxy resin curing accelerator	0.13

2. Gluing and baking: sizing speed of prepreg: 19 m/min;

3. prepreg control parameters:

gel time: 92 seconds;

resin content: 43 percent;

resin fluidity: 15 percent;

volatile components: 0.30 percent

4. Parameters of the pressing plate:

vacuum degree: -0.088 MPa;

pressure: 120-500psi

Temperature of the hot plate: 100 ℃ 220 DEG C

Curing time: >190 ℃ for 50 minutes.

5. The substrate performance parameters are shown in table 8 below:

TABLE 8

Comparative example 1

1. The compounding formulation proportions (in parts by weight solids) are shown in table 9 below:

TABLE 9

Raw material	Formulation ratio
		Phosphorus-containing epoxy resin	60
Basic epoxy resin	35
		Phenolic resin curing agent	28
Inorganic filler	35
		Epoxy resin curing accelerator	0.02

The phosphorus-containing epoxy resin is Dow XZ92530 epoxy resin, and the phenolic resin curing agent is PF8020 resin in the Shengquan chemical industry.

2. Gluing and baking:

sizing speed of prepreg: 16 m/min;

3. prepreg control parameters:

gel time: 100 seconds;

resin content: 44.5 percent;

resin fluidity: 24.0 percent;

volatile components: 0.35 percent;

4. pressing plate parameters:

vacuum degree: -0.092 MPa;

pressure: 130-450 psi;

temperature of the hot plate: 100 ℃ and 220 ℃;

curing time: >190 ℃ for 50 minutes.

5. The substrate performance parameters are shown in table 10 below:

watch 10

As is clear from Table 10, the flame retardancy of comparative example 1 was only V1 grade and was not satisfactory.

Comparative example 2

1. The compounding formulation proportions (in parts by weight) are shown in table 11 below:

TABLE 11

Raw material	Formulation ratio
		Phosphorus-containing epoxy resin	70
Basic epoxy resin	30
		Dicyandiamide curing agent	3
Inorganic filler	42
		Epoxy resin curing accelerator	0.04

The phosphorus-containing epoxy resin is Dow XZ92530 epoxy resin.

2. Gluing and baking:

sizing speed of prepreg: 15 m/min;

3. prepreg control parameters:

gel time: 110 seconds;

resin content: 44.0 percent;

resin fluidity: 23.0 percent;

volatile components: 0.45 percent;

4. parameters of the pressing plate:

vacuum degree: -0.092 MPa;

pressure: 130-450 psi;

temperature of the hot plate: 100 ℃ and 220 ℃;

curing time: >190 ℃ for 55 minutes.

5. The substrate performance parameters are shown in table 12 below:

TABLE 12

As is clear from Table 12, the solder heat resistance (PCT/3h, 288 ℃ immersion tin) of comparative example 2 is less than 10min, and is not satisfactory.

In conclusion, the invention provides the halogen-free epoxy resin adhesive, and the copper-clad plate manufactured by using the adhesive has good high heat resistance, and has good PCB processability and excellent anti-stripping strength. Is completely suitable for the PCB industry to be applied to halogen-free lead-free manufacture procedure and manufacture and processing of multilayer boards.

Claims

1. The halogen-free adhesive for manufacturing the copper clad laminate is characterized in that the adhesive comprises the following components in percentage by weight of solid (without solvent) in the total solid weight of the composition:

2. the halogen-free adhesive for manufacturing copper clad laminates as claimed in claim 1, wherein the physical property of the basic epoxy resin is required to have an epoxy equivalent EEW (g/eq) of between 160 and 210;

hydrolysable chlorine (dipropylene glycol methyl ether) was 300 MAX.

3. The halogen-free adhesive for manufacturing a copper clad laminate according to claim 1, wherein the novolac epoxy resin is any one or more of bisphenol a novolac epoxy resin, bisphenol F novolac epoxy resin or o-cresol novolac epoxy resin.

4. The halogen-free adhesive for manufacturing copper clad laminates as claimed in claim 1, wherein the epoxy equivalent weight of the tetrafunctional epoxy resin is between 180 and 220.

5. The halogen-free adhesive for manufacturing a copper clad laminate as claimed in claim 1, wherein the resin physical property of the phosphorous curing agent is that the hydroxyl equivalent weight (g/eq) is between 330 and 560;

hydrolyzable chlorine (dipropylene glycol methyl ether) 300 MAX;

the phosphorus content (wt%) is 8-10;

the solid content (wt%) is 54-60; the phosphorus-containing curing agent is bisphenol A phosphorus-containing phenolic resin, and the bisphenol A phosphorus-containing phenolic resin is prepared by reacting a phosphorus-containing compound with bisphenol A epoxy resin.

6. The halogen-free adhesive for manufacturing copper clad laminates according to claim 1, wherein the toughening agent is nano-scale core-shell rubber, and the nano-scale range of the core-shell rubber is 50-100 nm.

7. The halogen-free adhesive for making a copper clad laminate of claim 1 wherein the flame retardant is a phosphorus-containing flame retardant;

the epoxy resin curing accelerator is a curing accelerator for accelerating the curing of epoxy resin, and is any one or more of 2-ethyl-4-methylimidazole and 1-benzyl-2-methylimidazole;

the inorganic filler is any one or more of talc, quartz powder, ceramic powder, aluminum hydroxide or metal oxide particles.

8. The halogen-free adhesive for manufacturing a copper clad laminate according to claim 1, further comprising an organic solvent, wherein the organic solvent is such that the solid content of the halogen-free adhesive is 52% or more, and the organic solvent is any one or more of acetone, methyl ethyl ketone, toluene, xylene, methyl isobutyl ketone, propylene glycol methyl ether, and cyclohexanone.

9. The method for preparing a halogen-free adhesive for making a copper clad laminate of any one of claims 1-8, comprising the steps of:

firstly, stirring the part of the organic solvent, the dicyandiamide, the flexibilizer and the flame retardant for 30-80 minutes at the rotating speed of 800-1600 r/min and the temperature of 20-45 ℃ until the dicyandiamide is completely dissolved;

secondly, adding inorganic filler into the product of the first step and stirring for 30-60 minutes;

thirdly, adding the basic epoxy resin, the four-functional group epoxy resin, the phosphorus-containing curing agent and the novolac epoxy resin into the product obtained in the second step, and shearing and emulsifying the mixture for 2 to 4 hours at the rotation speed of 1200-1500 rpm and the temperature of 20 to 45 ℃;