Ultra-low temperature resistant high-life sealant and its preparation method and application

Abstract

The present invention belongs to the field of encapsulation technology, and particularly relates to a super low temperature resistant and high lifespan sealant, its preparation method and application. The present invention comprises component A and component B; Component A includes E51 epoxy resin, 6350 flexible epoxy resin, isophorone diisocyanate, KH560 silane coupling agent and organic zinc catalyst; Component B includes 704 imidazole curing agent, hydroxy silicone oil, carbon black and organic bismuth catalyst. In the present invention, the above-mentioned various component substances react with each other and are highly crosslinked, effectively improving the stability and high lifespan of the sealant during use. At the same time, the use of flexible epoxy resin and IPDI effectively improves the flexibility of the cured sealant, ensuring the sealing quality of the sealant in the super low temperature environment of liquid nitrogen. The use of hydroxy silicone oil for end-capping enables the sealant to contain silicon-carbon chains and silicon-oxygen bonds, reducing the aging of the glue and further improving the service life of the glue, and thus being able to easily wrap and seal the gap at the edge of the window seat completely.

Description

Technical Field

[0001] The present invention belongs to the field of packaging technology, and particularly relates to a super low temperature resistant and high life sealant, and its preparation method and application. Background Art

[0002] Cooled infrared detectors generally adopt the form of micro-dewar packaging. However, according to the requirements of the cooling method or the system coupling platform, infrared detectors in the form of shell packaging are becoming more and more common, and the packaging structure is also developing in the direction of being easy to produce, maintain and standardize. Compared with infrared detectors in the ground background, the optical signals detected by infrared detectors in the deep space background are extremely weak. Therefore, higher requirements are imposed on the transmittance of the window during the packaging of the detector. In addition, in order to enhance the detection sensitivity, the overall structure operates at a low temperature of 40K, and higher requirements are imposed on the thermal adaptation of the structure. For infrared detectors applied at a low temperature of 40K, indicators such as the mechanical strength, thermal adaptability, vacuum degree, airtightness, and reliability of electrical performance of the packaging structure are very important.

[0003] For example, the invention patent with the publication number CN114093954A discloses an infrared detector packaging component and an infrared detector having the same. The infrared detector packaging component includes: a housing component, a chip, and a lead ring. The housing component defines a chamber, the chip is disposed in the chamber, and the lead ring frame forms a part of the housing component. The chip is electrically connected to the lead ring to electrically lead out the chip from the chamber. Among them, the housing component is a low-expansion alloy part, and the housing component is provided with a window communicating with the chamber, and the window is covered by a sapphire window. According to the above infrared detector packaging component, it is packaged in the form of a shell, and the structure is compact. The housing component is made of a low-expansion alloy part, which has excellent mechanical strength, thermal conductivity and airtightness at low temperatures. Moreover, the thermal expansion coefficient of the housing component made of the low-expansion alloy part is close to that of the sapphire window at low temperatures, which can effectively reduce the stress of the sapphire window at low temperatures. In addition, the sapphire window has high compressive strength and can achieve a high transmittance. Another example is the invention patent with the bulletin number CN111426398B, which discloses a multi-color large-area array infrared detector and its preparation method, relating to the field of semiconductor optoelectronics. The detector includes a detector housing, an optical window, a rotating shaft, a transmission shaft, a drum, a multi-group focal plane chip packaging dewar device, a refrigeration device, a fixed shaft, a brush, a lens, a signal processing circuit and a display. In this application, focal plane chips of different detection bands are packaged in different dewars, and then the focal plane chip packaging dewar devices are arranged and welded on the axial surface of the drum in a certain axially symmetric manner. By rotating the drum, detection in different bands is realized, and finally, a multi-color infrared detection image is formed. In this application, multi-color can be achieved only by array embedding and parallel connection of monochromatic focal plane chip packaging dewar devices, saving process time and achieving low cost. In addition, the multi-color large-area array infrared focal plane detector in this application can also realize wavelength coupling and signal output in different bands according to the practical field.

[0004] However, at present, the sealing of the light-transmitting window of the infrared detector on the window seat still uses solder for brazing welding. Although it can ensure the fixation of the window and the service life of the product, the vacuum detection problem after sealing is relatively large, and the vacuum rate often fails to meet the standard. The surface of the window seat of the infrared detector is protected by gold plating to prevent the surface of the window seat from oxidizing. Since the wetting effect of the solder on gold is very strong, using the brazing solder method for welding and sealing easily causes the solder to overflow from the gap, which not only affects the appearance of the window seat but also results in poor vacuum tightness. Summary of the Invention

[0005] Aiming at the deficiencies of the above-mentioned existing technologies, the present invention provides a super-low-temperature-resistant and high-life sealant, its preparation method and application, aiming to solve the technical problem that when the light-transmitting window of the infrared detector is sealed on the window seat by using solder for brazing welding, it is easy for the solder to overflow from the gap, which not only affects the appearance of the window seat but also results in poor vacuum tightness.

[0006] The first technical solution provided by the present invention is a super-low-temperature-resistant and high-life sealant, and the specific technical solution is as follows:

[0007] The super-low-temperature-resistant and high-life sealant includes component A and component B; component A includes E51 epoxy resin, 6350 flexible epoxy resin, isophorone diisocyanate, KH560 silane coupling agent and organic zinc catalyst; component B includes 704 imidazole curing agent, hydroxy silicone oil, carbon black and organic bismuth catalyst.

[0008] In some embodiments, the mass ratio of component A to component B is 100:30.

[0009] In some embodiments, by mass, component A includes 40 - 70 parts of E51 epoxy resin, 20 - 40 parts of 6350 flexible epoxy resin, 10 - 20 parts of isophorone diisocyanate (IPDI), 0.5 - 3 parts of KH560 silane coupling agent, and 0.025 - 0.1 part of organic zinc catalyst.

[0010] In some embodiments, by mass, component B includes 8 - 12 parts of 704 imidazole curing agent, 15 - 25 parts of hydroxy silicone oil, 1 part of carbon black, and 0.005 - 0.02 part of organic bismuth catalyst.

[0011] The ultra-low temperature resistant and high-life sealant provided by the present invention has isocyanate groups in IPDI and epoxy resins that can react with silicone oil; the KH560 coupling agent can also react with silicone oil and can also be used as a coupling agent to improve compatibility; the 704 imidazole curing agent can not only be used as a curing agent for epoxy resin, but the tertiary amine group therein can also be used as a catalyst for the reaction of IPDI and hydroxyl silicone oil; the combination of two catalysts, organic bismuth and organic zinc, is more controllable for pre-curing and post-curing and is more environmentally friendly and safe compared with organic tin catalysts; carbon black has an absorption effect on light, can prevent the sealant from aging, effectively improve the service life of the sealant, and can effectively absorb the light refracted and diffracted through the window pane during the bonding process of the window pane and window seat, reducing its interference effect.

[0012] The second technical solution provided by the present invention is a preparation method of an ultra-low temperature resistant and high-life sealant, which is used to prepare the sealant described in the first technical solution. The specific technical solution is as follows:

[0013] The preparation method of an ultra-low temperature resistant and high-life sealant includes the following steps:

[0014] S1, dehydrate E51 epoxy resin, 6350 flexible epoxy resin, and hydroxyl silicone oil respectively;

[0015] S2, mix and stir isophorone diisocyanate, KH560 silane coupling agent, organic zinc catalyst, the E51 epoxy resin and 6350 flexible epoxy resin dehydrated in step S1 to obtain component A;

[0016] S3, mix and stir 704 imidazole curing agent, organic bismuth catalyst, carbon black and the hydroxyl silicone oil dehydrated in step S1 to obtain component B;

[0017] S4, mix component A and component B to obtain an ultra-low temperature resistant and high-life sealant.

[0018] In some embodiments, in step S1, the parameters of the dehydration treatment are as follows: the vacuum degree is 0.1 MPa, the temperature is 110 °C, and the time is 0.5 - 2 h.

[0019] In some embodiments, in steps S2 and S3, the stirring speed is 3000 r / min and the stirring time is 10 min.

[0020] In some embodiments, in step S4, component A and component B are stirred and foamed at 2000 r / min in a stirring and foaming machine for 4 min.

[0021] In the present invention, the substances of each component react with each other and are highly crosslinked, effectively improving the stability and long service life of the sealant. At the same time, flexible epoxy resin and IPDI are used, effectively improving the flexibility of the cured sealant and ensuring the sealing quality of the sealant in the ultra-low temperature environment of liquid nitrogen. End-capping with hydroxy silicone oil enables the sealant to contain silicon-carbon chains and silicon-oxygen bonds, reducing the aging of the glue and further improving the service life of the glue. The prepared ultra-low temperature resistant and long-life sealant has excellent high and low temperature resistance, low thermal expansion and contraction effect, excellent stability, good fluidity in the liquid state, and can easily and completely wrap and seal the gaps at the edge of the window seat.

[0022] The present invention provides a third technical solution for the application of an ultra-low temperature resistant and long-life sealant. Based on the sealant described in any one of claims 1-4, the specific technical solution is as follows:

[0023] Application of an ultra-low temperature resistant and long-life sealant, using the ultra-low temperature resistant and long-life sealant for the sealed connection between the light-transmitting window pane and the window seat of an infrared detector.

[0024] In some embodiments, it includes the following steps:

[0025] (1) Melt and uniformly distribute the solder at the place where the light-transmitting window pane is placed on the window seat, and then place the light-transmitting window pane above the solder for secondary melting;

[0026] (2) Inject the ultra-low temperature resistant and long-life sealant into the gap between the light-transmitting window pane and the window seat along the edge and fill it up, and then cure it;

[0027] (3) Press and cover the solder around the glue injection area, and heat it with a hot air gun until the solder melts and covers the surface of the ultra-low temperature resistant and long-life sealant.

[0028] The present invention adopts a new sealing method. Using the ultra-low temperature resistant and long-life sealant to ensure the sealing performance of the window seat and achieve the required vacuum degree; using solder for bottom sealing takes advantage of the good wettability of the solder to gold and has a certain sealing effect; using the ultra-low temperature resistant and long-life sealant for upper layer sealing takes advantage of the dense uniformity of the sealant to ensure complete filling of the edge gaps; covering with solder again on the upper layer also takes advantage of the good wettability of the solder to gold to connect the sealant and the window seat to form an integral whole and ensure no gaps. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 is a flow chart of the preparation method of the ultra-low temperature resistant and long-life sealant provided by the present invention;

[0030] Figure 2 is a schematic diagram of the packaging structure of Example 4 of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0031] To make the objectives, technical solutions and advantages of the present invention more clear and understandable, the present invention will be further described in detail below with reference to specific embodiments and the accompanying drawings.

[0032] Example 1

[0033] The super low-temperature resistant and high-life sealant provided in this example has the following specific technical solutions:

[0034] The super low-temperature resistant and high-life sealant includes component A and component B, and the mass ratio of component A to component B is 100:30.

[0035] By mass, component A includes 40 parts of E51 epoxy resin, 20 parts of 6350 flexible epoxy resin, 10 parts of isophorone diisocyanate (IPDI), 0.5 part of KH560 silane coupling agent, and 0.025 part of organic zinc catalyst.

[0036] By mass, component B includes 8 parts of 704 imidazole curing agent, 15 parts of hydroxyl silicone oil, 1 part of carbon black, and 0.005 part of organic bismuth catalyst.

[0037] This example also provides a preparation method for the above-mentioned super low-temperature resistant and high-life sealant, and the specific technical solutions are as follows:

[0038] The preparation method of the super low-temperature resistant and high-life sealant includes the following steps:

[0039] S1. Dehydrate E51 epoxy resin, 6350 flexible epoxy resin, and hydroxyl silicone oil at 110°C and a vacuum degree of 0.1 MPa for 0.5 - 2 h, and then cool to room temperature;

[0040] S2. Stir isophorone diisocyanate, KH560 silane coupling agent, organic zinc catalyst, the E51 epoxy resin and 6350 flexible epoxy resin dehydrated in step S1 at 3000 r / min for 10 min in a high-speed mixer to obtain component A;

[0041] S3. Stir 704 imidazole curing agent, organic bismuth catalyst, carbon black, and the hydroxyl silicone oil dehydrated in step S1 at 3000 r / min for 10 min in a high-speed mixer to obtain component B;

[0042] S4. During use, mix component A and component B at a mass ratio of 100:30 in a stirring and foaming machine at 2000 r / min for 4 min to obtain the super low-temperature resistant and high-life sealant.

[0043] Example 2

[0044] The super low-temperature resistant and high-life sealant provided in this example has the following specific technical solutions:

[0045] Ultra-low temperature resistant and high-life sealant, comprising component A and component B, with the mass ratio of component A to component B being 100:30.

[0046] By mass, component A includes 70 parts of E51 epoxy resin, 40 parts of 6350 flexible epoxy resin, 20 parts of isophorone diisocyanate (IPDI), 3 parts of KH560 silane coupling agent, and 0.1 part of organic zinc catalyst.

[0047] By mass, component B includes 8 - 12 parts of 704 imidazole curing agent, 15 - 25 parts of hydroxy silicone oil, 1 part of carbon black, and 0.005 - 0.02 part of organic bismuth catalyst.

[0048] This embodiment also provides a preparation method for the above ultra-low temperature resistant and high-life sealant. The specific technical solution is as follows:

[0049] The preparation method for the ultra-low temperature resistant and high-life sealant includes the following steps:

[0050] S1. Dehydrate E51 epoxy resin, 6350 flexible epoxy resin, and hydroxy silicone oil respectively at 110°C and a vacuum degree of 0.1 MPa for 0.5 - 2 h, and then cool to room temperature.

[0051] S2. Stir isophorone diisocyanate, KH560 silane coupling agent, organic zinc catalyst, the E51 epoxy resin and 6350 flexible epoxy resin dehydrated in step S1 at 3000 r / min for 10 min with a high-speed mixer to obtain component A.

[0052] S3. Stir 704 imidazole curing agent, organic bismuth catalyst, carbon black, and the hydroxy silicone oil dehydrated in step S1 at 3000 r / min for 10 min with a high-speed mixer to obtain component B.

[0053] S4. During use, mix component A and component B at a mass ratio of 100:30 and stir and foam at 2000 r / min for 4 min in a stirring and foaming machine to obtain the ultra-low temperature resistant and high-life sealant.

[0054] Example 3

[0055] The ultra-low temperature resistant and high-life sealant provided in this embodiment has the following specific technical solution:

[0056] Ultra-low temperature resistant and high-life sealant, comprising component A and component B, with the mass ratio of component A to component B being 100:30.

[0057] By mass, component A includes 50 parts of E51 epoxy resin, 30 parts of 6350 flexible epoxy resin, 15 parts of isophorone diisocyanate (IPDI), 2 parts of KH560 silane coupling agent, and 0.05 part of organic zinc catalyst.

[0058] By mass, Component B includes 10 parts of 704 imidazole curing agent, 20 parts of hydroxyl silicone oil, 1 part of carbon black, and 0.01 part of organic bismuth catalyst.

[0059] This embodiment also provides a preparation method of the above-mentioned ultra-low temperature resistant and high-life sealant, and the specific technical solution is as follows:

[0060] The preparation method of the ultra-low temperature resistant and high-life sealant includes the following steps:

[0061] S1. Dehydrate E51 epoxy resin, 6350 flexible epoxy resin, and hydroxyl silicone oil respectively at 110 °C and a vacuum degree of 0.1 MPa for 0.5 - 2 h, and then cool to room temperature;

[0062] S2. Stir isophorone diisocyanate, KH560 silane coupling agent, organic zinc catalyst, the E51 epoxy resin and 6350 flexible epoxy resin dehydrated in step S1 at 3000 r / min for 10 min in a high-speed mixer to obtain Component A;

[0063] S3. Stir 704 imidazole curing agent, organic bismuth catalyst, carbon black, and the hydroxyl silicone oil dehydrated in step S1 at 3000 r / min for 10 min in a high-speed mixer to obtain Component B;

[0064] S4. During use, mix Component A and Component B at a mass ratio of 100:30 in a stirring and degassing machine at 2000 r / min for 4 min to obtain the ultra-low temperature resistant and high-life sealant.

[0065] Example 4

[0066] This embodiment provides the application of the ultra-low temperature resistant and high-life sealant, as Figure 2 shown, and the specific technical solution is as follows:

[0067] 1. First, evenly melt and distribute less solder 3 at the place where the light-transmitting window pane 1 is placed on the window seat 2, and then place the light-transmitting window pane 1 above the solder 3 for secondary melting to ensure the back of the light-transmitting window pane 1 is in contact and sealed with the window seat 2.

[0068] 2. Inject the ultra-low temperature resistant and high-life sealant 4 in Examples 1 - 3 along the edge into the gap between the window pane and the window seat 2 until it is full, and then cure it.

[0069] 3. Then press the solder 3 around the shape of the glue-filled area, and heat it with a hot air gun until the solder 3 melts and covers the surface of the ultra-low temperature resistant and high-life sealant 4.

[0070] The hermetically sealed infrared detector of this embodiment is subjected to the performance test of the cryogenic-resistant and high-life sealant in Embodiments 1-3. The adhesion force is measured according to "GB / T 30774-2014 Determination of Sealant Adhesion", the seal leakage rate is measured by a helium leak detector, and the aging life test is carried out according to "GB / T 3512-2014 Vulcanized Rubber or Thermoplastic Rubber, Heat Aging and Heat Resistance Test in Hot Air", and the results are shown in Table 1.

[0071] Table 1 Performance test results of the cryogenic-resistant and high-life sealant in Embodiments 1-3 on the hermetically sealed infrared detector of this embodiment

[0072] Project Low temperature resistance (liquid nitrogen immersion) Adhesion Sealing leakage rate Aging life test Example 1 No change occurred in 5 min 23 Mpa <1.0x10-11pa·m3 / s 20 years in an environment of -20°C Example 2 No change occurred in 5 min 25 Mpa <1.0x10-11pa·m3 / s 21 years in an environment of -20°C Example 3 No change occurred in 5 min 21 Mpa <1.0x10-11pa·m3 / s 17 years in an environment of -20°C

[0073] As shown in Table 1, the cryogenic-resistant and high-life sealant of the present invention has a high cryogenic life, and both the adhesion force and the seal leakage rate meet the standards.

[0074] In addition, the processing of the window pane on the window seat of traditional infrared detectors is all carried out by soldering. During the soldering process, the soldering is sealed by the melting and flowing of the solder in a liquid state. The molten flow of the solder cannot be controlled manually during this process. Therefore, there is a possibility of incomplete sealing, and due to the special structure of the parts, it is impossible to repair the leaking part again later during the leakage process. Therefore, the probability of defective products still exists, which not only increases the cost, but also poses a potential hazard of leakage during later use. Currently, the unqualified rate of soldering every hundred window panes is more than 8%. Using the present invention for the processing of the window seat and window pane can completely solve the situation of the unqualified rate in production, and the sealant has a long life, which can provide a certain guarantee for the later use of the product.

[0075] The above are only the preferred and feasible embodiments of the present invention, and are not limitations on the present invention. The present invention is not limited to the above examples either. Those skilled in the art of this technology, within the scope of the essence of the present invention, the changes, modifications, additions or substitutions made should also fall within the protection scope of the present invention.

Claims

1. Ultra-low temperature resistant and high-life sealant, Characterized in that, It includes component A and component B; the mass ratio of component A to component B is 100:30, By mass, component A includes 40-70 parts of E51 epoxy resin, 20-40 parts of 6350 flexible epoxy resin, 10-20 parts of isophorone diisocyanate, 0.5-3 parts of KH560 silane coupling agent, and 0.025-0.1 part of organic zinc catalyst; component B includes 8-12 parts of 704 imidazole curing agent, 15-25 parts of hydroxy silicone oil, 1 part of carbon black, and 0.005-0.02 part of organic bismuth catalyst.

2. Preparation method of ultra-low temperature resistant and high-life sealant, a method for preparing the sealant according to claim 1, Characterized in that, It includes the following steps: S1, dehydrate E51 epoxy resin, 6350 flexible epoxy resin, and hydroxy silicone oil respectively; S2, mix and stir isophorone diisocyanate, KH560 silane coupling agent, organic zinc catalyst, the E51 epoxy resin and 6350 flexible epoxy resin dehydrated in step S1 to obtain component A; S3, mix and stir 704 imidazole curing agent, organic bismuth catalyst, carbon black and the hydroxy silicone oil dehydrated in step S1 to obtain component B; S4, mix component A and component B to obtain ultra-low temperature resistant and high-life sealant.

3. The preparation method of ultra-low temperature resistant and high-life sealant according to claim 2, Characterized in that, In step S1, the parameters of the dehydration treatment are as follows: the vacuum degree is 0.1 MPa, the temperature is 110 °C, and the time is 0.5-2 h.

4. The preparation method of ultra-low temperature resistant and high-life sealant according to claim 2, Characterized in that, In steps S2 and S3, the stirring speed is 3000 r / min and the stirring time is 10 min.

5. The preparation method of ultra-low temperature resistant and high-life sealant according to claim 2, Characterized in that, In step S4, component A and component B are stirred and foamed at 2000 r / min in a stirring and foaming machine for 4 min.

6. Application of ultra-low temperature resistant and high-life sealant, based on the sealant according to claim 1, Characterized in that, The ultra-low temperature resistant and high-life sealant is used for the sealed connection between the light-transmitting window pane and the window seat of an infrared detector.

7. The application of ultra-low temperature resistant and high-life sealant according to claim 6, Characterized in that, It includes the following steps: (1) Melt and evenly distribute the solder at the place where the light-transmitting window pane is placed on the window seat, and then place the light-transmitting window pane above the solder for secondary melting; (2) Inject the ultra-low temperature resistant and high-life sealant into the gap between the light-transmitting window pane and the window seat along the edge and fill it up, and cure it; (3) Press and cover the solder around the glue injection place, and heat it with a hot air gun until the solder melts and covers the surface of the ultra-low temperature resistant and high-life sealant.

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