TWM525600U - Reinforcing plates - Google Patents

Description

Reinforcing plate

The present invention relates to a matte black reinforcing plate for a printed circuit board, and more particularly to a reinforcing plate which is not easy to warp, has a special structure and has a shielding circuit effect.

Polyimine resin has high thermal stability and excellent insulation, mechanical strength and chemical resistance, so it is often used as an electronic processing material, such as an insulating layer for a flexible printed circuit. Polyimide resins can be further applied to electronic components, for example, as reinforcing materials for flexible printed circuit boards to avoid warping of flexible printed circuit boards.

Generally, the polyimide reinforced reinforcing sheets used in printed circuit boards can be generally classified into single-layer thick plates or multi-layer composite reinforcing plates, such as composite polyimide reinforced reinforcing plates. However, the current use of polyimide reinforced sheets is limited by the cost of the polyimide film, the thickness of the film and the transparency of the polyimide, and it is impossible to shield the circuit layout pattern, and the circuit layout pattern is easily copied by the industry. .

In addition, the polyimide reinforced plate is obtained from a polyimide film and then laminated, but the difference in thermal expansion coefficient between the two causes abnormality, and the flexible plate is still attached to the flexible circuit board, and there is still a soft circuit. The board produces a warp phenomenon.

Therefore, there is a need in the industry for a stiffener that avoids warpage of the flexible circuit board and has a line shielding function.

In order to overcome the above drawbacks, the present invention provides a maturity plate for a printed circuit board having a matte property, and the matte black reinforcing plate for a printed circuit board has a shielding circuit effect and a reduced printed circuit board warpage. The advantage of height.

In order to solve the above-mentioned technical problems and achieve the above effects, the present invention provides a reinforcing board for a printed circuit board, comprising: a black polyimine composite film; and a glue formed on the black polyimide film The adhesive layer, wherein the black polyimine composite film is composed of a two-black polyimine layer and a plurality of layers of interlaced polyimine layers and an adhesive layer, and the plurality of layers are interlaced. The imide layer and the subsequent layer are sandwiched between the two black polyimine layers.

The reinforcing plate of the present invention uses a black polyimine layer, thereby making the reinforcing plate of the present invention shieldable, and the best circuit shielding effect can be achieved without adding a process, and the second layer of the black polyimide layer is located. The plurality of layers are interlaced on the outer side of the polyimide layer and the outer layer of the adhesive layer, so that when the reinforcing plate of the present invention is applied to the circuit board, the circuit board can be provided with good support, so as to avoid the bonding of the reinforcing plate of the present invention. The board is warped or the warpage height is reduced.

10‧‧‧Black Polyimine Composite Film

11‧‧‧Black polyimine layer

12‧‧‧ Polyimine layer

13‧‧‧Next layer

14‧‧‧Adhesive layer

15‧‧‧ release layer

16‧‧‧ reinforcing plate

1 is a schematic cross-sectional view of a reinforcing plate of the present invention; and FIG. 2 is a cross-sectional view showing another embodiment of the reinforcing plate of the present invention. intention.

The embodiments of the present invention are described below by way of specific embodiments, and those skilled in the art can readily appreciate other advantages and functions of the present invention from the disclosure of the present disclosure.

It is to be understood that the structure, the proportions, the size and the like of the drawings are only used in conjunction with the disclosure of the specification for the understanding and reading of those skilled in the art, and are not intended to limit the implementation of the present invention. The qualifications are not technically meaningful. Any modification of the structure, change of the proportional relationship or adjustment of the size should remain in the creation without affecting the effectiveness and the purpose of the creation. The technical content disclosed can be covered. In the meantime, the terms "first", "second" and "upper" as used in this specification are for convenience of description only, and are not intended to limit the scope of the creation of the creation, the change or adjustment of the relative relationship, Under the content of no substantive change technology, it is also considered as the scope of implementation of this creation.

Referring to FIG. 1 , the reinforcing plate for a printed circuit board comprises: a black polyimine composite film 10; and an adhesive layer 14 formed on the black polyimide film, wherein the black layer The polyimine composite film 10 is composed of a two-black polyimine layer 11, and a plurality of layers of interlaced polyimine layer 12 and an adhesive layer 13, and the plurality of layers of interlaced polyimine layers are interlaced. 12 and an adhesive layer 13 are sandwiched between the two black polyimine layers 11.

In one embodiment, the black polyimine composite film has a total thickness of Z and is in accordance with the following formula (I): 2T+mX+nY=Z (I)

Wherein m is the number of layers of the polyimine layer, n is the number of layers of the layer, T is the thickness of the black polyimide layer, and X is the thickness of the polyimide layer, and Y is the thickness of the adhesive layer.

In the foregoing specific embodiments, T is 0.5 to 3 mils, X is 0.5 to 3 mils, and the Y value is more specifically, for example, when Z is 3 mils, T is 0.5 mils, m is 1 and X is 1mil, where n is 2 and Y is 0.5 mil; when Z is 4 mil, T is 0.5 mil, m is 1 and X is 1 mil, in this case n is 2 and Y is 1 mil; 5 mil, T is 0.5 mil, m is 1 and X is 2 mil, n is 2 and Y is 1 mil, but when m is 2 in this aspect, n is 3, X is 0.5 mil and Y is OK. It is 1 mil. In other embodiments, when Z is 6 mils and T is 0.5 mils, then m can be 2 or 3, or when T is 1 mil, then m can be 1 or 2; when Z is 7 mils and T is 0.5 mils Or 1 mil, then m can be 2 or 3; when Z is 8 mils and T is 0.5 to 2 mils, then m can be 2, 3 or 4; when Z is 9 mils and T is 0.5 to 2 mils, then m is 3 Or 4; when Z is 10 to 15 mils and T is 0.5 to 3 mils, m can be 1, 2, 3 or 4.

In a preferred embodiment of the reinforcing plate of the present invention, the black polyimine layer and the polyimide layer are preferably symmetrical, and the warpage height after the composite film is attached to the circuit board can be reduced. The two-layer matte black polyimide layer simultaneously helps protect the circuit pattern.

In a specific embodiment, the adhesive layer 14 has a thickness of 1 mil, and the adhesive layer 14 is a black adhesive layer. In the foregoing specific embodiment, the adhesive layer 14 contains an inorganic filler and an epoxy resin, and the black adhesive layer contains Black color developer and epoxy resin.

In the foregoing specific embodiment, the adhesive layer 13 is a black adhesive layer, and the black adhesive layer is a thermally hardened black adhesive layer, wherein the heat-hardened black adhesive layer contains a black developer and an epoxy resin. In the foregoing specific embodiment, the black developer contained in the black adhesive layer or the thermosetting black adhesive layer is a black pigment, a carbon powder or a carbon nanotube, and the black color is expressed by the total weight of the layer. The content of the agent is from 3 to 15%, and the glass transition temperature (Tg) of the black adhesive is more than 120 ° C, more preferably from 130 to 150 ° C, and the coefficient of thermal expansion is from 28 to 32 ppm / ° C, more preferably about 30 ppm / Good thermal stability at °C.

Referring to FIG. 2, in a specific embodiment, the reinforcing plate includes a release layer 15 attached to the adhesive layer 14. It is disclosed that the release layer 15 is a release paper or a release film. Through the arrangement of the release layer 15, the adhesiveness of the adhesive layer 14 can be protected, so as to facilitate adhesion during subsequent processing or application, and improve the processing adhesion, so as to be good in bonding to a circuit board or other pressing process. Bonding effect.

In the reinforcing plate 16 of the present invention, the type of material forming the black polyimine layer, the polyimide layer, the adhesive layer and the adhesive is not particularly limited, and it is preferred to use a halogen-free polyimine. The material and the adhesive are more preferably a self-adhesive and halogen-free adhesive. In addition, when the reinforcing sheet of the present invention uses the adhesive layer 13 containing the black developer and the adhesive layer 14, it is possible to have a better circuit pattern shielding effect without increasing the number of steps.

The matt black reinforcing plate used in the printed circuit board is produced by the following method: First, a matt black polyimine layer (Damai BK series; model BK-012/BK-075) is coated with a layer of heat-hardening black adhesive (Kunshan Yasen Electronic Material Technology Co., Ltd.), placed in an oven. After heating and baking to a B-stage, a hot roller is used to laminate with another polyimide, and so on. Finally, a matt black polyimide layer (Damai BK series; model BK-012/BK-075) is coated with a layer of heat-hardening black adhesive (Kunshan Yasen Electronic Material Technology Co., Ltd.) and placed in an oven. After heating and baking to a semi-cured state (B-stage), pressing with a hot roller and a composite film semi-finished product to a thickness of a desired matte black polyimine composite film; then, aging at 180 ° C for 1 hour; Finally, an adhesive layer was coated on the surface of the matte black polyimide composite film to form a matte black reinforcing plate sample for a printed circuit board.

Embodiments 1 to 11

The present inventive examples 1 to 11 were mainly produced in accordance with the thicknesses shown in Table 1 by the above method.

Comparative Examples 1 to 11 conventional reinforcing plates

The same manner as in the production methods of Examples 1 to 11, except that in the reinforcing sheets of Comparative Examples 1 to 11, the adhesive layer was made of pure gum (trade name: D3410) produced by SONY Co., Ltd., and Comparative Examples 1 to 11 were used. The reinforcing plate does not have a matte black polyimide layer (ie, black polyimide layer 11), and the thickness of the reinforcing plate is complemented by an adhesive layer of different thickness.

Test case

The reinforcing plate was cut into a size of 25 cm × 25 cm, and pressed at 180 ° C to a 3-Layer double-sided flexible copper foil substrate having a thickness of 74.5 ± 1 μm. On the other hand, the aging was carried out at 160 ° C, and the samples of the respective examples and the control samples were placed on a smooth surface. After standing for 20 minutes, the warpage height of the four corners was measured, and the flatness test was performed. In Table 2.

As shown in the results of Table 2, the difference in thermal expansion coefficient (CTE) between the polyimine film and the adhesive was small due to the fact that the total thickness of the black polyimine composite film was the same. Therefore, the warpage of the formed polyimine composite film is slowed down, and the difference in CTE between the SONY pure rubber and the polyimide film used in the comparative example is large, resulting in a large warpage height.

Therefore, when both were applied to the reinforcing copper foil substrate, in contrast to Comparative Examples 1 to 11, the inventive examples 1 to 11 were formed by the two black polyimide layers and the interlaced layers. The reinforcing plate of the black polyimide film can effectively reduce the warpage height of the copper foil substrate, thereby making the copper foil substrate have better flatness, and the flatness is more remarkable as the total thickness is increased.

The above description and examples are merely illustrative of the principles and functions of the present invention and are not intended to limit the invention. Any creation falling within the scope of this Creative Claim is covered by this Creative.

10‧‧‧Black Polyimine Composite Film

11‧‧‧Black polyimine layer

12‧‧‧ Polyimine layer

13‧‧‧Next layer

14‧‧‧Adhesive layer

Claims (15)

A reinforcing plate for a printed circuit board, comprising: a black polyimine composite film; and an adhesive layer formed on the black polyimine composite film, wherein the black polyimine composite film is composed of a black polyimine layer, and a plurality of layers of interlaced polyimine layers and an adhesive layer, and the plurality of layers of interlaced polyimine layers and subsequent layers are sandwiched between the two black poly Between the amine layers. The reinforcing plate according to claim 1, wherein the black polyimine composite film has a total thickness of Z and is in accordance with the following formula (I): 2T+mX+nY=Z (I) Wherein m is the number of layers of the polyimine layer, n is the number of layers of the layer, T is the thickness of the black polyimide layer, and T is 0.5 to 3 mil; X represents the poly The thickness of the amine layer, and X is 0.5 to 3 mils; and Y represents the thickness of the subsequent layer, and the Y value is determined according to the Z value. The reinforcing plate according to claim 1, wherein the adhesive layer has a thickness of 10 to 40 μm. The reinforcing plate according to claim 1, wherein the adhesive layer is a black adhesive layer. The reinforcing plate according to claim 4, wherein the black adhesive layer contains an inorganic filler and an epoxy resin. The reinforcing plate according to claim 5, wherein the black adhesive layer comprises a black color developing agent and an epoxy resin. The reinforcing plate according to claim 1, wherein the adhesive layer It is a black layer. The reinforcing plate according to claim 7, wherein the adhesive layer is a thermally hardened black adhesive layer. The reinforcing plate according to claim 8, wherein the thermosetting black adhesive layer comprises a black developer and an epoxy resin. The reinforcing plate according to claim 9, wherein the epoxy resin has a glass transition temperature of more than 120 °C. The reinforcing plate according to claim 10, wherein the epoxy resin has a thermal expansion coefficient of 28 to 32 ppm/°C. The reinforcing plate according to claim 6 or 9, wherein the black color developing agent is a black pigment, a carbon powder or a carbon nanotube. The reinforcing plate according to claim 6, wherein the black developer is contained in an amount of from 3 to 15% by weight based on the total weight of the black adhesive layer. The reinforcing sheet according to claim 9, wherein the black developer is contained in an amount of from 3 to 15% by weight based on the total weight of the thermally hardened black back layer. The reinforcing plate according to claim 1, wherein the reinforcing layer comprises a release layer attached to the adhesive layer.