PCB (printed circuit board) with black panel and preparation method of PCB

Abstract

The invention discloses a PCB (printed circuit board) with a black panel and a preparation method thereof, the panel of the PCB adopts a black patterned panel to replace black solder resist ink, the black patterned panel consists of insulating heat-conducting microspheres or / and black pigment microspheres, a resin base material and glass fiber cloth, the black panel is provided with a hollow position, and the black patterned panel is provided with a hollow hole. The black panel is glued with the double-sided copper-clad patterned circuit core board, the hollowed-out position is matched with the position of the welding metal PAD, the welding metal PAD is provided with a metal extension area, the metal extension area is in contact with the non-hollowed-out area of the black panel, a front heat conduction channel is established through the insulating heat conduction microsphere heat conduction network, and a back heat conduction channel is established through the insulating heat conduction microsphere heat conduction network. An infrared radiation channel is established through the black pigment microspheres. By preparing the black patterned panel, on the premise that the stray light extinction function is guaranteed, the front heat conduction and heat dissipation function is enhanced, and then the heat treatment problem of a traditional PCB is solved.

Description

Technical Field

[0001] The invention relates to the technical field of PCB board manufacturing and processing, in particular to a black panel PCB board and a manufacturing method thereof. Background Art

[0002] The existing method is to screen print or spray a layer of photosensitive black ink on one side of the PCB. The photosensitive black ink is made together with other color photosensitive inks when the solder mask is made, or it is sprayed in the subsequent processing and production process. Due to the characteristics of the photosensitive black ink itself, the energy required for exposure is high, the bottom of the ink is not completely photocured, and scratches are easily generated. Regardless of the method used, manual operations are inevitable in the production process, and the production environment requirements are high, otherwise garbage or scratches will be formed on the black ink surface of the board. At the same time, the ink thickness is uneven due to the height of the surface circuit, and the light reflection is inconsistent. Therefore, corresponding development for the black surface is the focus of the present invention. Summary of the invention

[0003] In order to solve the above technical problems, the present invention provides a black panel PCB board and a preparation method thereof. Specifically, the technical principle of the present invention is to prepare a black patterned panel containing thermal conductive microspheres and / or black pigment microspheres, and to construct a front thermal conductive channel and a uniform and reliable black matte layer, infrared radiation layer and ultraviolet protection layer, thereby realizing the preparation of a PCB board for medium and small power devices. The specific content of the invention is as follows:

[0004] A PCB board with a black panel comprises a black patterned panel, a double-sided copper-clad patterned circuit core board and a bottom solder resist ink layer.

[0005] Preferably, the black patterned panel has a hollow position corresponding to the welding metal PAD of the double-sided copper-clad patterned circuit core board.

[0006] More preferably, the welding metal PAD has a metal extension area, and the metal extension area is in contact with the non-hollowed-out area of ​​the black patterned panel.

[0007] More preferably, the metal extension region retains the largest area when copper-clad circuit patterning is performed while ensuring that the metal PAD does not short-circuit.

[0008] Preferably, the double-sided copper-clad patterned circuit core board achieves electrical conduction by filling metal in through holes, the front copper-clad circuit provides a welding metal PAD for power devices, and the back copper-clad circuit is used for external circuit driving.

[0009] Preferably, the bottom solder resist ink layer covers the back copper clad circuit, leaving a metal PAD for welding external circuit wires.

[0010] The preparation method of the PCB board of the present invention is as follows: the black patterned panel is glued to the double-sided copper-clad patterned circuit core board, and then further pressed by a fast press machine, and then the bottom surface is sprayed with solder resist ink to complete the preparation of the PCB substrate.

[0011] Preferably, a metal PAD for welding components is provided on one side of the double-sided copper-clad patterned circuit core board, and an external patterned circuit is connected to the opposite side through through-hole electroplating for connecting the circuit driving module, and one side of the external patterned circuit is protected by solder resist ink.

[0012] Preferably, the gluing uses DuPont LF0200 pure glue.

[0013] Preferably, the thickness of the double-sided copper-clad patterned circuit core board is 0.8-1.2 mm, the thickness of the copper cladding is 0.6-0.8 mil, and the thickness of the black patterned panel is 0.3-0.5 mm.

[0014] Preferably, the PCB board is used in lamps with small or medium power LED light sources.

[0015] More preferably, the surface layer height of the PCB board is lower than the light emitting surface height of the light source device soldered on the metal PAD.

[0016] The preparation method of the black patterned panel of the present invention is as follows:

[0017] S1) preparing a black profile, wherein the black profile is composed of a resin matrix, black inorganic microspheres and glass fiber cloth, wherein the inorganic microspheres are mixed with the resin matrix at a weight ratio of 8 to 20% by weight, and stirred to obtain a slurry;

[0018] S2) coating the resin substrate, pulling the glass fiber cloth to scrape the slurry, and controlling the slurry coating thickness by the scraper;

[0019] S3) Profile curing, using infrared light for rapid semi-curing, and then high temperature full curing at 250-280℃;

[0020] S4) patterning a black profile, wherein the black profile is subjected to a hole-opening process and hollowed out to reserve a welding metal PAD position;

[0021] Preferably, the black inorganic microsphere component is black insulating thermally conductive microspheres, and the black insulating thermally conductive microspheres are composed of one or more of black silicon carbide, black-gray boron carbide, and gray aluminum nitride.

[0022] More preferably, the component ratio of the black insulating thermally conductive microspheres in the slurry is 10-20%wt.

[0023] Preferably, the black inorganic microsphere components are insulating thermally conductive microspheres and insulating black pigment microspheres, and the insulating thermally conductive microspheres and the insulating black pigment microspheres are uniformly mixed in the resin matrix.

[0024] More preferably, the insulating thermally conductive microspheres are composed of one or more of aluminum oxide, silicon carbide, boron carbide, and aluminum nitride, and the insulating black pigment microspheres are composed of one or more of black titanium dioxide and insulating carbon black.

[0025] More preferably, the component ratio of the insulating thermally conductive microspheres in the slurry is 8-16% by weight, and the component ratio of the insulating black pigment microspheres in the slurry is 2-4% by weight.

[0026] Preferably, the black inorganic microsphere component is composed of insulating thermally conductive microspheres and conductive black pigment microspheres, the mixed slurry A of the insulating thermally conductive microspheres and the resin substrate is the bottom slurry component of the black profile, and the mixed slurry B of the conductive black pigment microspheres and the resin substrate is the top slurry component of the black profile.

[0027] More preferably, the thermally conductive microspheres are composed of one or more of aluminum oxide, silicon carbide, boron carbide, and aluminum nitride, and the black pigment microspheres are composed of one or more of graphite, graphene, and conductive carbon black.

[0028] More preferably, the black profile is firstly coated with the mixed slurry A on the bottom surface of the glass fiber cloth, and then the mixed slurry B is coated on the top surface after infrared semi-curing.

[0029] More preferably, the mixed slurry A completely wraps the glass fiber cloth, and the mixed slurry B is scraped and cured on the mixed slurry A layer.

[0030] More preferably, the ratio of the scraping thickness of the mixed slurry A to the scraping thickness of the mixed slurry B is 1 to 3:1.

[0031] More preferably, the component ratio of the insulating thermally conductive microspheres in the mixed slurry A is 10-20%wt, and the component ratio of the conductive black pigment microspheres in the mixed slurry B is 2-4%wt.

[0032] Preferably, the black inorganic microsphere component is composed of insulating thermally conductive microspheres and conductive black pigment microspheres, the mixed slurry A of the insulating thermally conductive microspheres and the resin substrate is the bottom slurry component of the black profile, and the mixed slurry C of the insulating thermally conductive microspheres, the conductive black pigment microspheres and the resin substrate is the top slurry component of the black profile.

[0033] More preferably, the thermally conductive microspheres are composed of one or more of aluminum oxide, silicon carbide, boron carbide, and aluminum nitride, and the black pigment microspheres are composed of one or more of graphite, graphene, and conductive carbon black.

[0034] More preferably, the black profile is firstly coated with the mixed slurry A on the bottom surface of the glass fiber cloth, and then the mixed slurry C is coated on the top surface after infrared semi-curing.

[0035] More preferably, the mixed slurry A completely wraps the glass fiber cloth, and the mixed slurry B is scraped and cured on the mixed slurry A layer.

[0036] More preferably, the ratio of the scraping thickness of the mixed slurry A to the scraping thickness of the mixed slurry C is 1 to 3:1.

[0037] More preferably, the insulating thermally conductive microsphere component ratio in the mixed slurry A is 10-20%wt, the conductive black pigment microsphere component ratio in the mixed slurry B is 2-4%wt, and the insulating thermally conductive microsphere component ratio is 8-16%wt.

[0038] Preferably, the resin matrix is ​​one of epoxy resin, polyimide and polytetrafluoroethylene.

[0039] By adopting the PCB board of the present invention, the reflected light uniformity, heat dissipation efficiency and mechanical stability of the LED light source system can be significantly improved.

[0040] Specifically, the beneficial effects and technical effects of the present invention include the following aspects:

[0041] 1. High extinction rate: By using black extinction material as the panel, the reflectivity of the PCB board to stray light can be significantly reduced, making the light of the LED light source system more uniform and soft.

[0042] 2. Good heat dissipation performance: By adding thermal conductive materials, the heat dissipation performance of the PCB board can be significantly improved to ensure the performance of the front heat conduction channel. At the same time, by entering the surface material with a high infrared radiation coefficient, the infrared radiation capacity is improved, and the front heat dissipation capacity is improved. Compared with the traditional PCB board, the central operating temperature of the LED light source is reduced by more than 10°C, extending the service life of the LED.

[0043] In summary, the present invention provides an innovative PCB board design and preparation method thereof, which solves the technical problems of the traditional LED light source system in terms of stray light hazards and poor PCB heat dissipation, and provides strong technical support for the development of LED light source systems. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0045] Figure 1 It is a schematic diagram of the local structure of the PCB board of the present invention.

[0046] Among them, 1-black patterned panel layer, 2-double-sided copper-clad patterned circuit layer, 3-core board glass fiber resin layer, 4-solder mask ink layer, 5-black panel hollow position, 6-device welding metal PAD, 7-external wire welding metal PAD. DETAILED DESCRIPTION

[0047] The endpoints and any values ​​of the ranges disclosed in the present invention are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of each range, the endpoint values ​​of each range and the individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, and these numerical ranges should be regarded as specifically disclosed in the present invention.

[0048] Example 1, a black panel PCB board prepared by the present invention, only insulating thermal conductive microspheres are used as inorganic microsphere additives:

[0049] S1) preparing a black profile, wherein the black profile is composed of an FR-4 epoxy resin matrix, black silicon carbide microspheres and No. 106 glass fiber cloth, wherein the resin matrix and the inorganic microspheres are mixed in a weight ratio of 8:2, and stirred to obtain a slurry;

[0050] S2) coating the resin substrate, pulling the glass fiber cloth at a speed of 1 mm / s to scrape the slurry, and controlling the slurry coating thickness to 0.5 mm by the scraper;

[0051] S3) Profile curing, using 2.5μm infrared light for 10s rapid semi-curing, and then high temperature full curing at 280℃;

[0052] S4) patterning a black profile, wherein the black profile is subjected to a hole-opening process, and a position for welding a metal PAD is reserved to prepare a black patterned panel;

[0053] S5) The black patterned panel is glued to the double-sided copper-clad patterned circuit core board, and then the two types of sheets are pressed together by a fast pressing machine, and then a solder mask ink layer is sprayed on the bottom surface to complete the preparation of the PCB board body.

[0054] In this embodiment, the thickness of the double-sided copper-clad patterned circuit core board is 1 mm, the thickness of the copper-clad layer is 0.69 mil, the thickness of the patterned black panel is 0.5 mm, the particle size D50 of the black silicon carbide microspheres is 7 um, the bonding material is DuPont LF0200 pure glue, and the metal PAD extension area is outside the etching area required for electrical isolation, covering the entire core board. The structural schematic diagram is shown in Figure 1 .

[0055] Example 2, a PCB board with a black panel prepared by the present invention, insulating thermal conductive microspheres and insulating black pigment microspheres as inorganic microsphere additives:

[0056] S1) preparing a black profile, wherein the black profile is composed of an FR-4 epoxy resin matrix, aluminum nitride microspheres, insulating carbon black and No. 106 glass fiber cloth, wherein the resin matrix, aluminum nitride microspheres and insulating carbon black are mixed in a weight ratio of 8:1.6:0.4, and stirred to obtain a slurry;

[0057] S2) coating the resin substrate, pulling the glass fiber cloth at a speed of 0.8 mm / s to scrape the slurry, and controlling the slurry coating thickness to 0.45 mm by the scraper;

[0058] S3) Profile curing, using 2.5μm infrared light for 20s rapid semi-curing, and then high temperature full curing at 275℃;

[0059] S4) patterning a black profile, wherein the black profile is subjected to a hole-opening process, and a position for welding a metal PAD is reserved to prepare a patterned black panel;

[0060] S5) The black patterned panel is glued to the double-sided copper-clad patterned circuit core board, and then the two types of sheets are pressed together by a fast pressing machine, and then a solder mask ink layer is sprayed on the bottom surface to complete the preparation of the PCB board body.

[0061] In this embodiment, the thickness of the double-sided copper-clad patterned circuit core board is 1 mm, the thickness of the copper clad layer is 0.69 mil, the thickness of the patterned black panel is 0.45 mm, the particle size D50 of the aluminum nitride microspheres is 10 um, the particle size of the carbon black is 30 nm, the bonding material is DuPont LF0200 pure glue, and the metal PAD extension area covers the entire core board outside the etching area reserved for electrical isolation.

[0062] Example 3, a black panel PCB board prepared by the present invention, insulating thermal conductive microspheres and conductive black pigment microspheres as inorganic microsphere additives:

[0063] S1) preparing a black profile, wherein the black profile is composed of an FR-4 epoxy resin matrix, aluminum nitride microspheres, graphite powder and No. 106 glass fiber cloth, wherein the resin matrix, aluminum nitride microspheres and insulating carbon black are mixed in a weight ratio of 8:2 and 9.6:0.4 to prepare a mixed slurry A and a mixed slurry B, and the mixture is stirred to obtain a slurry;

[0064] S2) coating the mixed slurry A, pulling the glass fiber cloth at a speed of 1 mm / s to scrape the mixed slurry A, and controlling the slurry coating thickness to be 0.35 mm by the scraper;

[0065] S3) Profile semi-curing, using 2.5μm infrared light for 10s rapid semi-curing;

[0066] S4) coating the mixed slurry B, pulling the glass fiber cloth at a speed of 0.9 mm / s to scrape the mixed slurry B, and controlling the slurry coating thickness to be 0.15 mm by the scraper;

[0067] S4) Profile curing, using 2.5μm infrared light for 10s rapid semi-curing, and then high temperature full curing at 250℃;

[0068] S6) patterning a black profile, wherein the black profile is subjected to a hole-opening process, and a position for welding a metal PAD is reserved to prepare a patterned black panel;

[0069] S7) The black patterned panel is glued to the double-sided copper-clad patterned circuit core board, and then the two types of sheets are pressed together by a fast pressing machine, and then a solder mask ink layer is sprayed on the bottom surface to complete the preparation of the PCB board body.

[0070] In this embodiment, the thickness of the double-sided copper-clad patterned circuit core board is 1 mm, the thickness of the copper cladding layer is 0.69 mil, the thickness of the patterned black panel is 0.5 mm, the particle size D50 of the aluminum nitride microspheres is 10 um, the particle size of the graphite powder is 5 nm, the bonding material is DuPont LF0200 pure glue, and the metal PAD extension area covers the entire core board outside the etching area reserved for electrical isolation.

[0071] Example 4, a black panel PCB board prepared by the present invention, only insulating thermal conductive microspheres are used as inorganic microsphere additives, and the welding metal PAD has no metal extension area:

[0072] S1) preparing a black profile, wherein the black profile is composed of an FR-4 epoxy resin matrix, black silicon carbide microspheres and No. 106 glass fiber cloth, wherein the resin matrix and the inorganic microspheres are mixed in a weight ratio of 8:2, and stirred to obtain a slurry;

[0073] S2) coating the resin substrate, pulling the glass fiber cloth at a speed of 1 mm / s to scrape the slurry, and controlling the slurry coating thickness to 0.5 mm by the scraper;

[0074] S3) Profile curing, using 2.5μm infrared light for 10s rapid semi-curing, and then high temperature full curing at 280℃;

[0075] S4) patterning a black profile, wherein the black profile is subjected to a hole-opening process, and a position for welding a metal PAD is reserved to prepare a patterned black panel;

[0076] S5) The black patterned panel is glued to the double-sided copper-clad patterned circuit core board, and then the two types of sheets are pressed together by a fast pressing machine, and then a solder mask ink layer is sprayed on the bottom surface to complete the preparation of the PCB board body.

[0077] In this embodiment, the thickness of the double-sided copper-clad patterned circuit core board is 1 mm, the thickness of the copper clad layer is 0.69 mil, the thickness of the patterned black panel is 0.5 mm, the particle size D50 of the black silicon carbide microspheres is 7 um, the bonding material is DuPont LF0200 pure glue, and the metal PAD has no extension area.

[0078] Example 5, a PCB board with a black panel prepared by the present invention, insulating thermally conductive microspheres and conductive black pigment microspheres as inorganic microsphere additives:

[0079] S1) preparing a black profile, wherein the black profile is composed of an FR-4 epoxy resin matrix, aluminum nitride microspheres, insulating carbon black and No. 106 glass fiber cloth, wherein the resin matrix, aluminum nitride microspheres and insulating carbon black are mixed in a weight ratio of 8:2 and 8:1.6:0.4 to prepare mixed slurry A and mixed slurry C, and the mixture is stirred to obtain a slurry;

[0080] S2) coating the mixed slurry A, pulling the glass fiber cloth at a speed of 1 mm / s to scrape the mixed slurry A, and controlling the slurry coating thickness to be 0.35 mm by the scraper;

[0081] S3) Profile semi-curing, using 2.5μm infrared light for 10s rapid semi-curing;

[0082] S4) coating the mixed slurry C, pulling the glass fiber cloth at a speed of 0.9 mm / s to scrape the mixed slurry C, and controlling the slurry coating thickness to 0.15 mm by the scraper;

[0083] S4) Profile curing, using 2.5μm infrared light for 10s rapid semi-curing, and then high temperature full curing at 250℃;

[0084] S6) patterning a black profile, wherein the black profile is subjected to a hole-opening process, and a position for welding a metal PAD is reserved to prepare a patterned black panel;

[0085] S7) The black patterned panel is glued to the double-sided copper-clad patterned circuit core board, and then the two types of sheets are pressed together by a fast pressing machine, and then a solder mask ink layer is sprayed on the bottom surface to complete the preparation of the PCB board body.

[0086] In this embodiment, the thickness of the double-sided copper-clad patterned circuit core board is 1 mm, the thickness of the copper cladding layer is 0.69 mil, the thickness of the patterned black panel is 0.5 mm, the particle size D50 of the aluminum nitride microspheres is 10 um, the particle size of the graphite powder is 5 nm, the bonding material is DuPont LF0200 pure glue, and the metal PAD extension area covers the entire core board outside the etching area reserved for electrical isolation.

[0087] Comparative Example 1, silica microspheres as inorganic microsphere additives:

[0088] S1) preparing a panel profile, wherein the panel profile is composed of an FR-4 epoxy resin matrix, silica microspheres and No. 106 glass fiber cloth, wherein the resin matrix and the inorganic microspheres are mixed in a weight ratio of 8:2, and stirred to obtain a slurry;

[0089] S2) coating the resin substrate, pulling the glass fiber cloth at a speed of 1 mm / s to scrape the slurry, and controlling the slurry coating thickness to 0.5 mm by the scraper;

[0090] S3) Profile curing, using 2.5μm infrared light for 10s rapid semi-curing, and then high temperature full curing at 270℃;

[0091] S4) patterning a panel profile, wherein the panel profile is subjected to a hole-opening process, and a position for welding a metal PAD is reserved to prepare a patterned panel;

[0092] S5) The patterned panel is glued to the double-sided copper-clad patterned circuit core board, and then the two types of sheets are pressed together by a fast pressing machine, and then a solder mask ink layer is sprayed on the bottom surface to complete the preparation of the PCB board body.

[0093] In this embodiment, the thickness of the double-sided copper-clad patterned circuit core board is 1 mm, the thickness of the copper clad layer is 0.69 mil, the thickness of the patterned panel is 0.5 mm, the particle size D50 of the silica microspheres is 7 um, the bonding material is DuPont LF0200 pure glue, and the metal PAD extension area covers the entire core board outside the etching area reserved for electrical isolation.

[0094] Comparative Example 2, silica microspheres and insulating black pigment microspheres as inorganic microsphere additives:

[0095] S1) preparing a black profile, wherein the black profile is composed of an FR-4 epoxy resin matrix, silica microspheres, insulating carbon black and No. 106 glass fiber cloth, wherein the resin matrix, silica microspheres and insulating carbon black are mixed in a weight ratio of 8:1.6:0.4, and stirred to obtain a slurry;

[0096] S2) coating the resin substrate, pulling the glass fiber cloth at a speed of 0.8 mm / s to scrape the slurry, and controlling the slurry coating thickness to 0.45 mm by the scraper;

[0097] S3) Profile curing, using 2.5μm infrared light for 20s rapid semi-curing, and then high temperature full curing at 275℃;

[0098] S4) patterning a black profile, wherein the black profile is subjected to a hole-opening process, and a position for welding a metal PAD is reserved to prepare a patterned black panel;

[0099] S5) The black patterned panel is glued to the double-sided copper-clad patterned circuit core board, and then the two types of sheets are pressed together by a fast pressing machine, and then a solder mask ink layer is sprayed on the bottom surface to complete the preparation of the PCB board body.

[0100] In this embodiment, the thickness of the double-sided copper-clad patterned circuit core board is 1 mm, the thickness of the copper clad layer is 0.69 mil, the thickness of the patterned black panel is 0.45 mm, the particle size D50 of the silica microspheres is 10 um, the particle size of the carbon black is 30 nm, the bonding material is DuPont LF0200 pure glue, and the metal PAD extension area covers the entire core board outside the etching area reserved for electrical isolation.

[0101] Comparative Example 3, only silica microspheres are used as inorganic microsphere additives, and the welding metal PAD has no metal extension area:

[0102] S1) preparing a panel profile, wherein the panel profile is composed of an FR-4 epoxy resin matrix, silica microspheres and No. 106 glass fiber cloth, wherein the resin matrix and the inorganic microspheres are mixed in a weight ratio of 8:2, and stirred to obtain a slurry;

[0103] S2) coating the resin substrate, pulling the glass fiber cloth at a speed of 1 mm / s to scrape the slurry, and controlling the slurry coating thickness to 0.5 mm by the scraper;

[0104] S3) Profile curing, using 2.5μm infrared light for 10s rapid semi-curing, and then high temperature full curing at 280℃;

[0105] S4) patterning a panel profile, wherein the panel profile is subjected to a hole-opening process, and a position for welding a metal PAD is reserved to prepare a patterned panel;

[0106] S5) The patterned panel is glued to the double-sided copper-clad patterned circuit core board, and then the two types of sheets are pressed together by a fast pressing machine, and then a solder mask ink layer is sprayed on the bottom surface to complete the preparation of the PCB board body.

[0107] In this embodiment, the thickness of the double-sided copper-clad patterned circuit core board is 1 mm, the thickness of the copper clad layer is 0.69 mil, the thickness of the patterned black panel is 0.5 mm, the particle size D50 of the silica microspheres is 7 um, the bonding material is DuPont LF0200 pure glue, and the metal PAD has no extension area.

[0108] In comparative example 4, a common PCB board is prepared by using black solder resist ink. The thickness of the black solder resist ink layer is 0.1 mm, and the black solder resist ink layer contains 4% insulating carbon black.

[0109] In comparative example 5, a common PCB board is prepared by using green solder resist ink, and the thickness of the green solder resist ink layer is 0.1 mm.

[0110] For the 5*5 equally spaced lamp bead welding points prepared in Examples 1 to 5 and Comparative Examples 1 to 5, 0.2w 3528 lamp beads were used as the test light source, with a total of 5W ordinary bulb lamps. Two thermocouple contact test points were set at the center and the edge to measure the surface temperature. At the same time, the visible light reflectivity was measured at the unhollowed area to obtain the thermal conductivity and visible light extinction ability of the PCB board test. Specific data are shown in Table 1.

[0111] Table 1

[0112]

[0113] It can be seen from Table 1 that Example 5 achieves the best infrared radiation value and visible light extinction ability, and is one of the best solutions for layered coating of mixed slurry A and mixed slurry C of the present invention. Carbon black, as a strong light absorber, has the strongest absorption capacity for visible light and ultraviolet light. Example 2 can achieve good extinction ability through one-time mixing. Comparing the center temperature and the edge temperature, the temperature difference of the embodiment with the metal extension zone is significantly reduced compared with that of Example 4, which shows that the functional design effect of the metal extension zone is obvious. Since comparative examples 1 and 3 do not add thermal conductive microspheres and black pigments (infrared radiation ability), their surface heat accumulation is large and the temperature is high. Although ordinary black ink materials have strong infrared radiation ability, the ink layer is thin and its heat capacity is low, so the heat dissipation ability is poor, resulting in actual performance close to that of green ink. From the data comparison in Table 1, it can be seen that the technical solution of the present invention can significantly improve the defects of the traditional solution.

[0114] The above shows and describes the basic principles and main features of the present invention and the advantages of the present invention. It should be understood by those skilled in the art that the present invention is not limited to the above embodiments. The above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention to be protected. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A black panel PCB board, characterized in that: It includes a black patterned panel, a double-sided copper-clad patterned circuit core board and an underlying solder resist ink layer. The black patterned panel is prepared by coating glass fiber cloth with a slurry mixed with a resin matrix and inorganic microspheres. The inorganic microspheres are composed of thermally conductive insulating microspheres and / or black pigment microspheres. The welding metal PAD of the double-sided copper-clad patterned circuit core board matches the hollow position of the black patterned panel, and the welding metal PAD has a metal extension area that contacts the non-hollow position of the black patterned panel.

2. The method for preparing a PCB according to claim 1, wherein: The resin matrix is ​​one of epoxy resin, polyimide and polytetrafluoroethylene.

3. The method for preparing a PCB board according to claim 1, characterized in that: The thermally conductive insulating microspheres are one or more of aluminum oxide, aluminum nitride, boron nitride, and silicon carbide. The addition amount of the thermally conductive insulating microspheres is 8% to 20% of the total weight of the slurry.

4. The method for preparing a PCB board according to claim 1, characterized in that: The black pigment microspheres are one or more of black silicon carbide, black titanium dioxide, carbon black, graphite, and graphene, and the addition amount of the black pigment microspheres is 2% to 4% of the total weight of the slurry.

5. A method for preparing a PCB board for preparing the black panel according to claim 1, characterized in that: The following steps are involved: S1) preparing a black panel profile, mixing inorganic microspheres with a resin matrix, stirring to obtain a slurry, and drawing a low-density warp and weft glass fiber cloth to achieve coating of the slurry by scraping; S2) patterning a black panel, wherein the black panel profile is subjected to a hole-perforating process, and a position of a welding metal PAD is reserved by hollowing out, and the welding metal PAD has an extended area, and the extended area is in contact with an unperforated area of ​​the black panel core material; S3) PCB board gluing: the patterned black panel is glued to the double-sided copper-clad patterned circuit core board, and then the two types of board materials are pressed together by a fast pressing machine; S4) spraying solder resist ink on the other side of the PCB board to complete the preparation of the PCB board.

6. The method for preparing a PCB board according to claim 5, characterized in that: In step S1), the inorganic microspheres are composed of thermally conductive insulating microspheres and insulating black pigment microspheres, which are mixed with a resin matrix to form a slurry, and are coated on both sides with glass fiber cloth by scraping.

7. The method for preparing a PCB board according to claim 5, characterized in that: In step S1), the inorganic microspheres are composed of thermally conductive insulating microspheres and conductive black pigment microspheres, and the thermally conductive insulating microspheres and the conductive black pigment microspheres are mixed with a resin substrate in proportion to prepare mixed slurry A and mixed slurry B, respectively. The mixed slurry A and mixed slurry B are coated on both sides of the glass fiber cloth relative to each other.

8. The method for preparing a PCB board according to claim 7, characterized in that: The mixed slurry A may be coated with glass fiber cloth, and the layer thickness ratio of the mixed slurry A to the mixed slurry B is 1 to 3:

1.

9. The method for preparing a PCB board according to claim 7, characterized in that: The thermally conductive insulating microspheres and the resin substrate are prepared into a mixed slurry A in proportion, and the thermally conductive insulating microspheres and the conductive black pigment microspheres are mixed with the resin substrate to prepare a mixed slurry C. The coating layer thickness ratio of the mixed slurry A and the mixed slurry C is 1 to 3:

1.

10. The PCB board of the black panel according to any one of claims 1 to 4, characterized in that: The PCB board is applied to small and medium power LED light source lamps.

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