CN104804660B - Cover protection film for printed circuit boards with high temperature resistance and high reflectivity - Google Patents

Abstract

The invention provides a covering protection film for a printed circuit board with high temperature resistance and high reflectivity, which comprises a high temperature resistant polymer film, wherein the melting point is more than 260 ℃; a high-reflection polymer composite material layer containing a first reflective pigment, which is arranged on one side surface of the high-temperature-resistant polymer film; the adhesive layer is arranged on one side surface of the high-temperature-resistant polymer film, which is far away from the high-reflectivity polymer layer; the whole reflectivity of the covering protection film for the printed circuit board with high temperature resistance and high reflectivity is more than 89%, and the absorptivity of the high-temperature-resistant polymer film is less than 35%. Therefore, after the surface adhesive is combined with a printed circuit board and subjected to a surface adhesion process of a light source element at 160-320 ℃, the reflectivity of the light source element in the wave band is more than 89%, and yellowing and delamination phenomena are not generated.

Description

Cover protection film for printed circuit boards with high temperature resistance and high reflectivity

technical field

The invention relates to a covering protective film for printed circuit boards, especially a covering protective film for printed circuit boards with high temperature resistance and high reflectivity.

Background technique

In order to achieve specific light transmission and light distribution effects in the light source modules of electronic products in the prior art, secondary optical elements are required. However, when the light generated by the light source element of the light source module passes through the secondary optical element, there will be light loss such as light absorption and light scattering, which will not only cause the light to be wasted and cannot be used effectively, but also affect the overall electronic product In addition, after the light generated by the light source element of the light source module passes through the secondary optical element, its luminous intensity attenuates with the increase of the transmission distance, so it is necessary to increase the luminous intensity of the light source of the light source module To ensure the light output efficiency of electronic products. For example, in the backlight module of a display, the light guide plate can be used to achieve the effect of surface light source and uniform light, but the light absorption and light scattering of the light guide plate will cause light loss.

As shown in Figure 10, in order to reduce the light loss caused by the secondary optical element, the prior art provides a printed circuit board with a reflective ink layer for the light source element of the light source module of the electronic product, the reflective ink layer 81 is The ink is printed and formed on a surface of the printed circuit board 82, and the light source element 83 of the light source module is arranged on the surface through a surface mount (SMT, Surface Mount Technology) process; Scattered light in the surface direction can be reflected by the reflective ink layer 81 and travel away from the printed circuit board 82 , thereby improving the light extraction efficiency and light color rendering of electronic products.

However, the reflective ink layer 81 of the prior art has the following disadvantages:

1. After the surface adhesion process of the light source element 83, since the operating temperature of the surface adhesion process is between 160 and 320°C, the reflective ink layer 81 formed by ink printing will undergo yellowing (Yellowing), thus reducing the reflective ink layer. 81 reflectivity (Reflection).

2. Increase the reflectivity by increasing the thickness of the printed reflective layer. When the thickness of the printed reflective layer is thickened, the ink will not be used in the forming and cutting process and the printed circuit board 82 when the reflective layer is not supported by the substrate. When flexing (R angle less than 0.5mm), the reflective layer is prone to embrittlement.

Contents of the invention

In view of the above-mentioned shortcomings of the prior art, the object of the present invention is to provide a cover protective film for printed circuit boards with high temperature resistance and high reflectivity, which does not produce yellowing after the surface adhesion process, and still has high reflectivity , and has better structural strength so it is not easy to be brittle.

In order to achieve the above-mentioned purpose of the invention, the technical means adopted by the present invention is to make the printed circuit board cover protection film with high temperature resistance and high reflectivity, including:

A high-temperature-resistant polymer film with a thickness of 2 to 125 micrometers (μm), a melting point greater than 260°C, and two sides;

A high-reflective polymer composite material layer is arranged on one side of the high-temperature-resistant polymer film, and its thickness is 2 to 30 microns, which contains a first reflective coloring material, and the refractive index of the first reflective coloring material is greater than 1 ;

An adhesive layer, which is arranged on the other side of the high-temperature-resistant polymer film away from the high-reflection polymer composite material layer, and has a thickness of 10 to 75 microns;

Wherein, in the band where the overall reflectivity of the protective film covering the printed circuit board with high temperature resistance and high reflectivity is greater than 89%, the absorption rate of the high temperature resistant polymer film is less than 35%.

According to the present invention, the high temperature resistance refers to the ability to pass through a surface adhesion process with a process temperature of 160 to 320° C. and a process time of 10 to 180 seconds without yellowing and delamination.

According to the present invention, the high reflectivity is in the wavelength band between 415 and 700 nanometers, and the reflectivity is between 89% and 100%. Preferably, in the wave band of 415 to 700 nanometers, the absorption rate of the high temperature resistant polymer film is less than 35%, and the overall reflectance of the cover protective film for printed circuit boards with high temperature resistance and high reflectivity is 89% to 100%.

Based on the above, through the use of the high-reflection polymer composite material layer containing the first reflective coloring material, the ratio of the light from the light source element being reflected by the high-reflection polymer composite material layer is increased, and the light from the light source element penetrates through the high-reflection polymer material. The proportion of the composite material layer; through the use of high temperature resistant polymer films with an absorption rate of 35% or less in the band where the overall reflectivity of the protective film covering the printed circuit board with high temperature resistance and high reflectivity is greater than 89%, By reducing the absorption of the penetrating light in this wavelength band and enabling multiple reflections, it is possible to increase the overall light output intensity of electronic products, reduce the power of light source components of electronic products, and improve the light color rendering of electronic products. Wherein, and the melting point of the high-temperature-resistant polymer film is greater than 260°C, so that the covering protection film for printed circuit boards with high-temperature resistance and high reflectivity of the present invention can have no yellowing and no peeling after the surface adhesion process is carried out. Advantages of the layer phenomenon.

In addition, through the setting of the high temperature resistant polymer film, the high reflective polymer composite material layer can be supported, so that the covering protective film for printed circuit boards with high temperature resistance and high reflectivity can Covering protective film for printed circuit boards with high temperature resistance and high reflectivity is not easy to be brittle and cracked.

In addition, by making the adhesive layer have a thickness of 10 to 75 microns, the effect of covering the circuit gap on the printed circuit board can be achieved.

Preferably, the thickness tolerance of the high-reflection polymer composite material layer is ±2 microns, which has good thickness uniformity. Compared with the reflective inks in the prior art, it can further improve the reflection uniformity of light .

Preferably, the adhesive layer contains a second light-reflecting colorant, and the high-temperature-resistant polymer film contains a third light-reflecting colorant.

Preferably, the refractive index of the second light-reflecting colorant is greater than 1, and the refractive index of the third light-reflecting colorant is greater than 1.

Preferably, the first reflective colorant accounts for 20 to 70 volume percent of the entire high-reflective polymer composite material layer, the second reflective colorant accounts for 10 to 50 volume percent of the adhesive layer as a whole, and the third reflective colorant Accounting for 1 to 20 volume percent of the whole high temperature resistant polymer film.

Preferably, the first reflective coloring material includes titanium dioxide, barium sulfate, strontium sulfate, aluminum oxide, zirconium dioxide, zinc oxide, Magnesium oxide, calcium oxide, boron nitride, aluminum nitride, calcium carbonate, aluminum hydroxide and magnesium hydroxide Hydroxide) in one or a combination of several.

Preferably, the second reflective coloring material comprises titanium dioxide, barium sulfate, strontium sulfate, aluminum oxide, zirconium oxide, zinc oxide, magnesium oxide, calcium oxide, boron nitride, aluminum nitride, calcium carbonate, aluminum hydroxide and hydrogen One or a combination of magnesium oxide.

Preferably, the third reflective coloring material comprises titanium dioxide, barium sulfate, strontium sulfate, aluminum oxide, zirconium oxide, zinc oxide, magnesium oxide, calcium oxide, boron nitride, aluminum nitride, calcium carbonate, aluminum hydroxide and hydrogen One or a combination of magnesium oxide.

According to the present invention, the covering protection film for printed circuit boards with high temperature resistance and high reflectivity has the characteristics of no yellowing after the surface adhesion process, high reflectivity, and better structural strength. It has the characteristics of low thickness, which can meet the trend of light and thin in the industry. Preferably, the high temperature resistant polymer film has a thickness of 6 to 25 microns, the high reflective polymer composite material layer has a thickness of 6 to 20 microns, and the adhesive layer has a thickness of 10 to 35 microns. More preferably, the high temperature resistant polymer film has a thickness of 6 to 12 microns.

According to the present invention, the high reflective polymer composite material layer includes a first reactive functional group resin and a first crosslinking agent. The reactive functional groups of the first resin with reactive functional groups include carboxy groups, amine groups, epoxy groups, hydroxyl groups and double bonds. one or a combination of several. The first crosslinking agent is an aromatic compound or aliphatic compound containing two or more crosslinking reactive functional groups, and the crosslinking reactive functional groups of the first crosslinking agent include carboxy group, anhydride group ), amine group (amine group), hydroxyl group, epoxy group (epoxy group), isocyanate group (isocyanate) and double bond (double bond) in one or a combination of several.

According to the present invention, the adhesive layer includes a second resin with reactive functional groups and a second crosslinking agent, and the reactive functional groups of the second resin with reactive functional groups include carboxyl groups, amine groups, epoxy groups and hydroxyl groups one or a combination of several. The second crosslinking agent is an aromatic compound or aliphatic compound containing two or more crosslinking reactive functional groups, and the crosslinking reactive functional groups of the second crosslinking agent include carboxyl, acid anhydride, amine, hydroxyl, ring One or more combinations of oxygen and isocyanate groups.

Preferably, the high temperature resistant polymer film contains one or more of polyphenylene sulfide (polyphenylene sulfide), polyethylene naphthalate (polyethylene naphthalate) and polyether ether ketone (poly(ether ether ketone)). combination of species.

According to the present invention, the covering protective film for printed circuit boards with high temperature resistance and high reflectivity may include a release layer, the release layer is arranged on the side of the adhesive layer away from the high temperature resistant polymer film, the The release layer includes release materials such as plastic release film or release paper, but is not limited thereto.

According to the present invention, the covering protective film for printed circuit boards with high temperature resistance and high reflectivity can be applied to rigid circuit boards and flexible circuit boards at the same time.

Description of drawings

FIG. 1 is a cross-sectional schematic side view of a cover protection film for a printed circuit board with high temperature resistance and high reflectivity according to Embodiment 1 of the present invention.

FIG. 2 is a cross-sectional side view of the high-temperature-resistant and high-reflectivity printed circuit board cover protection film attached to the printed circuit board according to Embodiment 1 of the present invention.

FIG. 3 is a partial cross-sectional side view of the surface-adhesive process of the cover protection film for the printed circuit board with high temperature resistance and high reflectivity according to Embodiment 1 of the present invention.

FIG. 4 is a reflectance spectrum diagram of the cover protection film for printed circuit boards with high temperature resistance and high reflectivity according to Examples 4 to 7 of the present invention. In the figure, the symbol "■" indicates the embodiment 4, the symbol "●" indicates the embodiment 5, the symbol "▲" indicates the embodiment 6, and the symbol "▼" indicates the embodiment 7.

5 is an absorption spectrum diagram of a high temperature resistant polymer film covered with a protective film for a printed circuit board with high temperature resistance and high reflectivity according to embodiments 4 to 6 and embodiments 8 to 11 of the present invention. In the figure, the symbol "●" indicates Example 8 using 50 micron PET, the symbol "■" indicates Example 9 using 125 micron PET, the symbol "◆" indicates Example 10 using 50 micron PPS, and the symbol "▲" Examples 4 to 6 that use 12.5 micron polyimide are marked, and the symbol "▼" marks Example 11 that uses 12.5 micron PEEK.

6 is a reflectance spectrum diagram of a high temperature resistant polymer film covering a protective film for a printed circuit board with high temperature resistance and high reflectivity according to Embodiment 6 and Embodiment 11 of the present invention. In the figure, the embodiment 11 is marked with the symbol "■" and the embodiment 6 is marked with the symbol "▲".

7 is a reflectance spectrum diagram of a high temperature resistant polymer film covered with a protective film for a printed circuit board with high temperature resistance and high reflectivity according to Examples 8 to 10 of the present invention. In the figure, the symbol "■" indicates the embodiment 10, the symbol "▲" indicates the embodiment 8, and the symbol "●" indicates the embodiment 9.

FIG. 8 is a partial cross-sectional side view of a printed circuit board with a reflective ink layer according to Comparative Example 1 of the present invention.

9 is a reflectance spectrum diagram of printed circuit boards with reflective ink layers in Comparative Examples 1 and 2 of the present invention. In the figure, the symbol "▲" indicates comparative example 1 before heat resistance test, the symbol "▼" indicates comparative example 1 after heat resistance test, and the symbol "■" indicates comparative example 2 before heat resistance test , The symbol "●" indicates the comparative example 2 after the heat resistance test was carried out.

FIG. 10 is a schematic partial cross-sectional side view of a printed circuit board with a reflective ink layer in the prior art.

Explanation of main reference symbols

10 Cover protection film for printed circuit boards

11 High temperature resistant polymer film

12 layers of highly reflective polymer composite material

13 Adhesive layer

10A Overlay protection film for printed circuit boards

11A High temperature resistant polymer film

12A highly reflective polymer composite layer

13A Adhesive layer

20 printed circuit board

30 first sample

30A first sample

20A PCB

40A light source element

50 printed circuit boards

60 layers of reflective ink

70 light source element

81 reflective ink layer

82 printed circuit board

83 light source components

detailed description

In order to have a clearer understanding of the technical features, purpose and beneficial effects of the present invention, the technical solution of the present invention is described in detail below, but it should not be construed as limiting the scope of the present invention.

Example 1

Please refer to shown in Fig. 1, in the present embodiment, the printed circuit board cover protective film 10 of the present invention with high temperature resistance and high reflectivity includes a high temperature resistant polymer film 11, a high reflective polymer composite material Layer 12, an adhesive layer 13 and a release layer. The high temperature resistant polymer film 11 has two corresponding sides, the high reflective polymer composite material layer 12 and the adhesive layer 13 are respectively arranged on the two sides of the high temperature resistant polymer film 11, and the release layer is provided On the side of the adhesive layer 13 away from the high temperature resistant polymer film 11 .

In this embodiment, the preparation method of the covering protective film 10 for printed circuit boards with high temperature resistance and high reflectivity, the specific steps include:

Provide the high temperature resistant polymer film 11;

The high-reflection polymer composite material layer 12 is disposed on one side of the high-temperature-resistant polymer film 11. The specific steps include: first mixing the first resin with reactive functional groups, the first cross-linking agent and the catalyst to form a first mixed solution; the first reflective colorant is dispersed in the first mixed solution by physical dispersion technology to form a pre-high reflective polymer composite solution; the pre-high reflective polymer composite solution is covered on the resistant by surface coating technology A pre-high reflective polymer composite material layer 12 is formed on one side of the high temperature polymer film 11; the pre-high reflective polymer composite material layer is heated, so that the first reactive functional group resin and the first crosslinking agent are Curing by crosslinking reaction to form the high reflective polymer composite material layer 12;

The adhesive layer 13 is disposed on the side of the high-temperature-resistant polymer film 11 away from the high-reflection polymer composite material layer 12. The specific steps include: first mixing the second resin with reactive functional groups and the second cross-linking agent to form The second mixed solution; the second reflective coloring material is dispersed in the second mixed solution by physical dispersion technology to form a viscous liquid; the viscous liquid is covered on one side of the high temperature resistant polymer film by surface coating technology to forming the adhesive layer 13; and

Attaching the release layer on the side of the adhesive layer 13 away from the high temperature resistant polymer film 11;

Wherein, the high temperature-resistant polymer film 11 is a polyimide film with a thickness of 12.5 microns and a melting point greater than 260°C. The first resin with reactive functional groups is a polyester-polyol copolymer with hydroxyl groups. The first crosslinking agent is polyisocyanate (HDI polyisocyanate), the first reflective pigment (reflected pigment) is titanium dioxide (TiO ₂ ) powder with a refractive index greater than 1, and the high reflective polymer composite material layer The thickness of 12 is 20 microns, and the titanium dioxide powder contained in the high reflective polymer composite material layer 12 is 20 volume percent (vol%). The second resin with reactive functional group is epoxy resin with epoxy group, the second crosslinking agent is diamine with two amine groups, and the second reflective The colorant is calcium carbonate powder with a refractive index greater than 1. The thickness of the adhesive layer 13 can be about 25 microns, and a thickness of 23 microns to 27 microns with a difference of plus or minus 2 microns is acceptable in related processes. The thickness of the adhesive layer 13 used in the present embodiment is 25 microns, the calcium carbonate powder contained in the adhesive layer 13 is 10 volume percent, and the release layer can be a plastic release film or a release paper etc. profiles. In this embodiment, release paper is used as the release layer.

Please refer to Fig. 1 and shown in Fig. 2, in the present embodiment, the release layer of the printed circuit board with high temperature resistance and high reflectivity covering protective film 10 is peeled off to obtain a peeled off release layer. The covering protective film 10 for printed circuit boards with high temperature resistance and high reflectivity, and then the covering protective film 10 for printed circuit boards with high temperature resistance and high reflectivity after peeling off the release layer, after the lamination process, Attach the adhesive layer 13 to one side of a printed circuit board 20, and then perform a thermal curing process to allow the adhesive layer 13 to undergo a cross-linking reaction and cure to obtain a first sample 30. With the first sample 30 to perform reflectance detection.

In the present embodiment, described reflectance detects, and its used equipment is Hitachi U-4100 spectrometer (Hitachi U-4100spectrometer), and the standard test piece used is Hitachi original barium sulfate standard sheet (reflectivity 100 %), the reflectance detection value is at a wavelength of 550 nanometers, measuring the relative comparison value of the overall reflectivity of the printed circuit board cover protection film 10 with high temperature resistance and high reflectivity relative to the standard sheet. The test results are shown in Table 1.

Example 2

This embodiment is similar to the embodiment 1, the difference is that: the titanium dioxide powder contained in the high reflective polymer composite material layer 12 as the first reflective coloring material is 30% by volume. The test results of this embodiment are shown in Table 1.

Example 3

This embodiment is similar to the embodiment 1, the difference is that: the titanium dioxide powder contained in the high reflective polymer composite material layer 12 as the first reflective coloring material is 60% by volume. The test results of this embodiment are shown in Table 1.

The test result of table 1 embodiment 1 to embodiment 3

Example 4

Please refer to shown in Fig. 3, present embodiment is generally the same as embodiment 1, and its difference is: the high reflective polymer composite material layer 12A of the printed circuit board of described tool high temperature resistance and high reflectivity covering protective film 10A The thickness is 13 microns. In this embodiment, the reflectance detection is to measure the overall reflectance of the cover protection film for printed circuit boards with high temperature resistance and high reflectivity at a wavelength of 400 to 700 nanometers.

In addition, as shown in FIG. 3 , in this embodiment, a high temperature resistance test is additionally carried out, which makes the first sample 30A undergo a surface adhesion process, so that the light source element 40A and the adhesive layer 13A are located on the printed circuit board 20A. on the same side. In the surface adhesion process, the process temperature is 300° C., and the process time is 30 seconds.

In addition, in this embodiment, the high temperature resistant polymer film 11A is also measured with a Hitachi U-4100 spectrometer (Hitachi U-4100spectrometer), and the high temperature resistant polymer film 11A of this embodiment is a polyimide film .

In addition, in this embodiment, according to the JIS-K7105 specification of the Japanese Industry Standard (JIS), the cover protection film 10A for printed circuit boards with high temperature resistance and high reflectivity is tested as a whole through a high temperature resistance test at 300°C. Whether it turns yellow afterward, and according to the relationship between the NBS color difference unit and the sensory color difference of CIE 1976 (Lab), the ΔE value is less than 1.5, which means very slight to slight sensory color difference.

The test results of this embodiment are shown in Table 2, Figure 4 and Figure 5 .

Example 5

This embodiment is similar to Embodiment 4, the difference is that the thickness of the high reflective polymer composite material layer is 20 microns. The test results of this embodiment are shown in Table 2, Figure 4 and Figure 5 .

Example 6

This embodiment is similar to Embodiment 4, the difference is that the thickness of the high reflective polymer composite material layer is 29 microns. The test results of this embodiment are shown in Table 2 and FIGS. 4 to 6 .

Example 7

This embodiment is similar to Embodiment 4, the difference is that the thickness of the high reflective polymer composite material layer is 32 microns. The test results of this embodiment are shown in Table 2, Figure 4 and Figure 5 .

The test result of table 2 embodiment 4 to embodiment 7

Example 8

This embodiment is generally the same as Embodiment 4, and the difference is that the high-temperature-resistant polymer film is a polyethylene terephthalate (PET) film, and the polyethylene terephthalate film The thickness is 50 microns, and the thickness of the high reflective polymer composite material layer is 29 microns. The test results of this embodiment are shown in Table 3, Fig. 5 and Fig. 7 .

Example 9

This embodiment is generally the same as Embodiment 8, the difference being that the thickness of the polyethylene terephthalate film as a high temperature resistant polymer film is 125 microns. The test results of this embodiment are shown in Table 3, Fig. 5 and Fig. 7 .

The test result of table 3 embodiment 8 and embodiment 9

Example 10

This embodiment is generally the same as Embodiment 1, the difference is that the high temperature resistant polymer film is poly(p-phenylene sulfide), PPS, and the thickness of the polyphenylene sulfide film is 50 microns, and Its melting point is greater than 260°C. The thickness of the high reflective polymer composite material layer is 29 microns. The adhesive layer uses the second mixed solution directly as the adhesive liquid, and is formed by covering the adhesive liquid on one side of the high-temperature-resistant polymer film by wet coating. The second light-reflecting layer contained in the adhesive layer The coloring material is 0 volume percent, that is, the adhesive layer does not contain the second reflective coloring material.

In this embodiment, the reflectance detection is to measure the overall reflectance of the covering protection film for printed circuit boards with high temperature resistance and high reflectivity in the wave band of 400 to 700 nanometers. In addition, in this embodiment, the reflectance detection described above is also performed on the polyphenylene sulfide film. In addition, in this embodiment, the high temperature resistance test as described in Example 4 is carried out, and the absorptivity test as described in Example 4 is also carried out on the polyphenylene sulfide film. The test results of this embodiment are shown in Table 4, Fig. 5 and Fig. 7 .

The test result of table 4 embodiment 10 and embodiment 11

Example 11

This embodiment is similar to that of Embodiment 10, except that the high-temperature-resistant polymer film is a poly(ether ether ketone) (PEEK) film, and the melting point of the polyether ether ketone film is greater than 300°C. The test results of this embodiment are shown in Table 4, Fig. 5 and Fig. 6 .

Comparative example 1

Please refer to shown in Figure 8, in this comparative example, a printed circuit board 50 with a reflective ink layer 60 is provided, and ink (manufactured by Guanpin Material Technology Co., Ltd., model T-75) is used on one side of a printed circuit board 50 ) printing and forming a reflective ink layer 60 .

In this comparative example, the printed circuit board 50 with the reflective ink layer 60 is directly tested for reflectance. Then make the printed circuit board 50 with the reflective ink layer 60 carry out high temperature resistance detection: through the surface adhesion process, the light source element 70 and the reflective ink layer 60 are positioned on the same side of the printed circuit board 50 (as shown in Figure 8 ). After the printed circuit board 50 with the reflective ink layer 60 is tested for high temperature resistance, the reflectance is tested again, and the yellowing is detected according to JIS-K7105.

In this comparative example, for the reflectance detection, the incident light is visible light with a wavelength between 415 and 700 nanometers. In the surface adhesion process, the process temperature is 288° C., and the process time is 10 seconds. The test results of this comparative example are shown in Figure 9 and Table 5.

The test result of table 5 comparative example 1 and comparative example 2

Comparative example 2

The difference between this comparative example and comparative example 1 is that the ink used is manufactured by China Taiwan Sun Ink Co., Ltd., and the model is PSR-4000. The test results of this comparative example are shown in Figure 9 and Table 5.

As shown in FIG. 9 , before the high temperature test, the highest reflectances of Comparative Example 1 and Comparative Example 2 are both below 80% in the wave band from 415 to 700 nanometers. However, after the high temperature test, the highest reflectances of Comparative Example 1 and Comparative Example 2 both dropped below 77% in the wave band from 415 to 700 nanometers. As shown in Table 5, after the high temperature test, the ΔE values of Comparative Example 1 and Comparative Example 2 were 3.8 and 2.6 respectively, both of which were greater than 1.5, and then Comparative Example 1 and Comparative Example 2 produced yellowing; After the test, the reflectance of Comparative Example 1 and Comparative Example 2 decreased due to yellowing.

From Table 1 to Table 5, Figure 4 to Figure 7 and Figure 9, it can be seen that when the wavelength is 550 nanometers, the printing materials with high temperature resistance and high reflectivity of Embodiment 1 to Embodiment 3 and Embodiment 5 to Embodiment 11 The reflectivity of the covering protection film for the circuit board all reaches more than 89%, and the reflectivity of the printed circuit board with the reflective ink layer of comparative example 1 and comparative example 2 is lower than 80%, then the tool resistance of embodiment 1 to embodiment 11 The cover protection film for printed circuit boards with high temperature resistance and high reflectivity has better reflectivity than the printed circuit boards with reflective ink layer in Comparative Example 1 and Comparative Example 2. After the high-temperature test, the ΔE values of the high-temperature-resistant and high-reflectivity cover protection films for printed circuit boards in Examples 4 to 11 were all less than 1.5, and no yellowing occurred. And the tolerance of the thickness of the reflective ink layer of Comparative Example 1 and Comparative Example 2 is ± 15 microns, while the tolerance of the thickness of the high reflective polymer composite material layer of Examples 1 to 11 is ± 2 microns, showing Comparative Example 1 And the thickness uniformity of the reflective ink layer of Comparative Example 2 is worse than that of Examples 1 to 11, and then Examples 1 to 11 have better thickness uniformity than Comparative Examples 1 and 2.

As shown in Table 1, the covering protective film for printed circuit boards with high temperature resistance and high reflectivity of embodiment 1, the content of titanium dioxide powder contained in its high reflective polymer composite material layer is 20 volume percent, and incident When the wavelength of light is 550 nanometers, the reflectivity of the printed circuit board cover protection film 10 with high temperature resistance and high reflectivity of embodiment 1 for this waveband is more than 89%, while the reflectivity of embodiment 2 and embodiment 3 has The content of titanium dioxide powder contained in the high-reflection polymer composite material layer covered with protective film for printed circuit boards with high temperature resistance and high reflectivity is all higher than that of Example 1, which are 30 and 60 volume percent respectively, but when the incident light When the wavelength is 550 nanometers, the reflectivity of the cover protective film 10 of the printed circuit board with high temperature resistance and high reflectivity of embodiment 2 and embodiment 3 is the same as that of the printed circuit board with high temperature resistance and high reflectivity of embodiment 1. The protective films used for circuit boards are quite close, being 90.2% and above 90.5% respectively; it can be seen that when the content of titanium dioxide powder contained in the high-reflection polymer composite material layer is 20% by volume, the reflectivity can reach 89%. above.

As shown in Table 2 and Figure 4, under the wavelength band between 420 and 495 nanometers, the cover protection film with high temperature resistance and high reflectivity of embodiment 4 has a reflectivity of more than 89%; Under the wave band of 420 to 600 nanometers, the covering protective film for printed circuit boards with high temperature resistance and high reflectivity of embodiment 5 has a reflectivity of more than 89%; The high-temperature and high-reflectivity covering protective film for printed circuit boards has a reflectivity of more than 89%; in the wave band from 415 to 700 nanometers, the high-temperature-resistant and high-reflective covering protective film for printed circuit boards of embodiment 7 It has a reflectivity of more than 89%, and the thicknesses of the high reflective polymer composite material layers of Examples 4 to 7 are respectively 13 microns, 20 microns, 29 microns and 32 microns, and the high temperature resistant polymer films of Examples 4 to 7 Both are polyimide films with a thickness of 12.5 microns.

As shown in FIG. 5 , when the wavelength of the incident light is between 415 and 520 nanometers, the absorptivity of the polyimide film with a thickness of 12.5 microns is above 35%.

It can be seen that, under the wavelength band of 420 to 495 nanometers, a polyimide film with a thickness of 12.5 microns and high temperature resistance and a high reflectivity cover protection film for printed circuit boards has a reflectivity of more than 89%. For: the thickness of the high reflective polymer composite material layer must be more than 30 microns. It can be further deduced that when the thickness of the high-reflection polymer composite material layer of a high-temperature-resistant and high-reflectivity cover protective film for printed circuit boards is less than 30 microns, under the wave band from 415 to 700, the resistant The high-temperature and high-reflectivity cover protection film for printed circuit boards has a reflectivity of 89% or more on the condition that the absorptivity of the high-temperature-resistant polymer film must be 35% or less.

As shown in Table 3, Figure 5 and Figure 7, the thickness of the high temperature resistant polymer film in Example 8 is 50 microns, and the thickness of the high temperature resistant polymer film in Example 9 is 125 microns. And under the wave band of 330 to 700, the absorptivity of the high-temperature-resistant polymer film covering the protective film of the printed circuit board with high-temperature resistance and high reflectivity of embodiment 8 is below 35%, and the high-temperature-resistant high-molecular film of embodiment 9 The absorptivity of the high-temperature-resistant polymer film covering the protective film for printed circuit boards with anti-corrosion properties and high reflectivity is also 35% or less. And under the wave band of 330 to 700, the reflectivity of the cover protection film with high temperature resistance and high reflectivity of the printed circuit board of embodiment 8 and embodiment 9 is more than 89%; the thickness of the high temperature resistant polymer film is shown The difference will not affect the reflectivity of the high-temperature-resistant and high-reflectivity printed circuit board cover protection film of embodiment 8 and embodiment 9.

Please refer to table 3, table 4 and shown in Fig. 5, the high temperature resistant polymer film of embodiment 8 is the thick polyethylene terephthalate film of 50 microns, and the high temperature resistant polymer film of embodiment 10 is 50 microns Thick polyphenylene sulfide film, both have less than 35% absorption in the 415 to 700 nm band. Please refer to Figure 7 and Table 3, under the wave band of 415 to 700 nanometers, the reflectivity of the high temperature resistance and high reflectivity printed circuit board cover protection film of embodiment 8 and embodiment 10 is more than 89%. . After the heat resistance test (surface adhesion, 300°C/30 seconds), it was found that the polyethylene terephthalate film in Example 8 had insufficient temperature resistance and thermal expansion and contraction were too large, thereby causing high reflection Delamination occurs between the polymer composite layer and the polyethylene terephthalate film, between the polyethylene terephthalate film and the adhesive layer, or between the adhesive layer and the printed circuit board (de -lamination), and the polyphenylene sulfide film of Example 10 does not have delamination phenomenon. After comparison, it is known that the melting point of the polyethylene terephthalate film is less than 260 ° C, while the polyphenylene sulfide film The melting point of the film is greater than 260°C; this proves that when the melting point of the high-temperature resistant polymer film is greater than 260°C, the covering protective film for printed circuit boards with high temperature resistance and high reflectivity can carry out surface adhesion process without delamination Phenomenon.

Please refer to table 2 and shown in table 4, the high temperature resistant polymer film of embodiment 6 is the polyethylene terephthalate film of 12.5 microns, and the high temperature resistant polymer film of embodiment 11 is the polyether ether of 12.5 microns For the ketone film, the melting point of the polyethylene terephthalate film is less than 260°C, and the melting point of the polyether ether ketone film is greater than 260°C. After the high temperature resistance test, no delamination occurred in the cover protective films for printed circuit boards with high temperature resistance and high reflectivity in Example 6 and Example 11. However, as shown in Table 2, Figure 5 and Figure 6, under the wave band of 415 to 520 nanometers, the absorption rate of the high temperature resistant polymer film of Example 6 is greater than 35%, and under the wave band of 415 to less than 420 nanometers , the reflectivity of the cover protection film with high temperature resistance and high reflectivity of the printed circuit board of embodiment 6 does not reach 89%, that is, under the wave band of 415 to 700 nanometers, its reflectivity is not completely more than 89%; please Referring to Table 4, Figure 5 and Figure 6, under the wave band of 415 to 700 nanometers, the absorptivity of the high temperature resistant polymer film of Example 11 is below 35%, and the high temperature resistant and high reflective film of Example 11 The reflectivity of the cover protective film for printed circuit boards is above 89%.

Please refer to Table 1 to Table 4, the adhesive layers of Examples 1 to 8 all contain 10 volume percent of the second reflective colorant, while the adhesive layers of Examples 10 and 11 do not. Taking the wavelength of 550 nanometers as an example, the reflectivity of the high temperature resistance and high reflectivity printed circuit board covering protection film of embodiment 1 to embodiment 3 and embodiment 5 to embodiment 8 is greater than 89%. 10 and Example 11 have high temperature resistance and high reflectivity printed circuit board cover protective film reflectivity is also greater than 89%, showing that the reflectivity and the reflectivity of embodiment 1 to embodiment 3 and embodiment 5 to embodiment 8 The reflectivity of Example 10 and Example 11 is quite close. Therefore, the use of the second reflective colorant can increase the reflectance of the cover protection film for printed circuit boards of the present invention with high temperature resistance and high reflectivity.

Based on the above, it is confirmed by reflectivity detection and high temperature resistance detection that compared with Comparative Example 1 and Comparative Example 2, Embodiment 1 to Embodiment 3 and Embodiment 5 to Embodiment 11 all have better reflectivity and high temperature resistance ; And confirmed by the comparison between Example 1 to Example 3 and Example 5 to Example 11, through the melting point is more than 260 ℃ and under the wave band of 415 to 700 nanometers has absorptivity below 35% high temperature resistance The use of the polymer film and the high-reflection polymer composite material layer containing the first reflective pigment can make the covering protective film for printed circuit boards with high temperature resistance and high reflectivity of the present invention, at a wavelength of 415 to 700 nanometers Under the wavelength band, it has the advantages of more than 89% reflectivity and the surface adhesion process (the process temperature is 300 ° C, the process time is 30 seconds) without yellowing and delamination, which can increase the overall quality of electronic products. Light intensity, reduce the power of light source components of electronic products and improve the light color rendering of electronic products.

Claims (16)

1. the use in printed circuit board covering protection film of a kind of tool heat-resisting quantity and high reflectance, wherein includes：

One fire resistant polymer film, its thickness are 12.5 to 125 microns, and fusing point is more than 260 DEG C, and there are two sides；

One high reflection polymer composite layer, is arranged on the one side of the fire resistant polymer film, and its thickness is 11 to 31 Micron, wherein comprising one first reflective colorant and one first tool reactive functional group resin, the refractive index of the first reflective colorant It is more than 1, the first tool reactive functional group resin is the polyester-polyalcohols resin copolymer for having hydroxyl；

One adhesion coating, its are arranged at another side of the fire resistant polymer film away from the high reflection polymer composite layer On, its thickness is 10 to 75 microns；

Wherein, it is more than 89% in the overall reflectance of the use in printed circuit board covering protection film of tool heat-resisting quantity and high reflectance Wave band, the absorbance of the fire resistant polymer thin film is less than 35%.

2. according to claim 1 tool heat-resisting quantity and high reflectance use in printed circuit board covering protection film, wherein, The adhesion coating includes one second reflective colorant.

3. according to claim 2 tool heat-resisting quantity and high reflectance use in printed circuit board covering protection film, wherein, The refractive index of the second reflective colorant is more than 1.

4. according to claim 1 tool heat-resisting quantity and high reflectance use in printed circuit board covering protection film, wherein, The fire resistant polymer film includes one the 3rd reflective colorant.

5. according to claim 4 tool heat-resisting quantity and high reflectance use in printed circuit board covering protection film, wherein, The refractive index of the 3rd reflective colorant is more than 1.

6. the use in printed circuit board of tool heat-resisting quantity according to any one of claim 1 to 5 and high reflectance is covered and is protected Shield film, wherein, the first reflective colorant accounts for 20 to 70 overall volume basis of the high reflection polymer composite layer Than.

7. tool heat-resisting quantity according to Claims 2 or 3 and the use in printed circuit board covering protection film of high reflectance, its In, the second reflective colorant accounts for 10 to 50 overall percents by volume of the adhesion coating.

8. tool heat-resisting quantity according to claim 4 or 5 and the use in printed circuit board covering protection film of high reflectance, its In, the 3rd reflective colorant accounts for 1 to 20 overall percent by volume of the fire resistant polymer film.

9. the use in printed circuit board of tool heat-resisting quantity according to any one of claim 1 to 5 and high reflectance is covered and is protected Shield film, wherein, the thickness of the high reflection polymer composite layer is 11 to 20 microns.

10. the use in printed circuit board of tool heat-resisting quantity according to any one of claim 1 to 5 and high reflectance is covered and is protected Shield film, wherein, the thickness of the adhesion coating is 10 to 35 microns.

The use in printed circuit board of 11. tool heat-resisting quantities according to any one of claim 1 to 5 and high reflectance is covered protects Shield film, wherein, the high reflection polymer composite layer include one first cross-linking agent, first cross-linking agent include containing The aromatic compound of two or more crosslinking reactivity functional group and the aliphatic containing two or more crosslinking reactivity functional group The combination of one or more in compound, the crosslinking reactivity functional group of first cross-linking agent include carboxyl, anhydride, amine The combination of one or more in base, hydroxyl, epoxy radicals, isocyanate group and double bond.

The use in printed circuit board of 12. tool heat-resisting quantities according to any one of claim 1 to 5 and high reflectance is covered protects Shield film, wherein, the adhesion coating includes one second tool reactive functional group resin, the second tool reactive functional group resin bag Contain an at least reactive functional group, the reactive functional group includes one or more in carboxyl, amido, epoxy radicals and hydroxyl Combination.

13. tool heat-resisting quantities according to claim 12 and the use in printed circuit board covering protection film of high reflectance, its In, the adhesion coating includes one second cross-linking agent, and second cross-linking agent is included containing two or more crosslinking reactivity functional group's The combination of one or more in aromatic compound and the aliphatic compound containing two or more crosslinking reactivity functional group, The crosslinking reactivity functional group of second cross-linking agent is included in carboxyl, anhydride, amido, hydroxyl, epoxy radicals and isocyanate group The combination of one or more.

The use in printed circuit board of 14. tool heat-resisting quantities according to any one of claim 1 to 5 and high reflectance is covered protects Shield film, wherein, the fire resistant polymer film includes polyphenylene sulfide and/or polyether-ether-ketone.

The use in printed circuit board of 15. tool heat-resisting quantities according to any one of claim 1 to 5 and high reflectance is covered protects Shield film, wherein, the fire resistant polymer film includes PEN.

The use in printed circuit board of 16. tool heat-resisting quantities according to any one of claim 1 to 5 and high reflectance is covered protects Shield film, wherein, in 415 to 700 nanometers of wave band, fire resistant polymer film absorption rate less than 35%, tool heat-resisting quantity and The overall reflectance of the use in printed circuit board covering protection film of high reflectance is more than 89%.