Epoxy acrylate modified ultraviolet curing dust catching glue suitable for interior of camera and preparation method of epoxy acrylate modified ultraviolet curing dust catching glue

Abstract

The invention discloses an epoxy acrylate modified ultraviolet curing dust catching adhesive suitable for the interior of a camera and a preparation method of the epoxy acrylate modified ultraviolet curing dust catching adhesive. The epoxy acrylate modified ultraviolet curing dust catching adhesive comprises the following raw material components in parts by weight: 30.0-40.0 parts of high-reactivity low-viscosity epoxy acrylate resin; 18.0 to 25.0 parts of polycaprolactone modified polyurethane acrylate with low Tg (glass transition temperature) and low volatility; 20.0 to 30.0 parts of a reactive diluent with high light transmittance and low volatility; 2.5 to 4.0 parts of a low migration compound type photoinitiator; 1.8-5.2 parts of a functional auxiliary agent special for a camera; the high-transmittance and low-volatility reactive diluent is a mixture prepared from ethoxylated ethyoxyl acrylate and tripropylene glycol diacrylate according to the mass ratio of (1.2 to 1.8): 1. And in the ultraviolet light curing process (365nm, energy is 800-1000mJ / cm), the volatile matter is less than or equal to 5mg / m < 2 >.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of adhesives, and relates to an epoxy acrylate modified ultraviolet light curing dust capturing adhesive suitable for the inside of a camera and a preparation method thereof. BACKGROUND

[0002] As a precise optical imaging device, the cleanliness inside the camera directly determines the imaging quality (even if micron-level dust adheres to the lens surface, image sensor (CMOS / CCD) or infrared filter, it will cause problems such as dark spots, glare, and resolution reduction in the picture). The existing dust control of the camera mainly relies on a dust-free workshop (such as Class 100) in the production link, but there are the following core pain points: (1) dust residue after assembly: during the assembly process of the camera module, such as the bonding of the lens and the lens seat, and the welding of the sensor and the PCB, a small amount of resin debris and metal dust will still be generated, and they cannot be completely removed through subsequent cleaning; (2) dust release in long-term use: the buffer foam and adhesive layer inside the camera are prone to release small molecule volatile substances and condense into dust under changes in temperature and humidity (such as the long-term use of a mobile phone camera in an environment of-20℃ to 60℃), or to produce particles due to material aging and shedding.

[0003] A kind of ultraviolet light curing dust capturing adhesive is disclosed in Chinese invention patent with application number 202110779741.4, comprising: acrylate resin prepolymer, polyurethane resin, macromolecular mercaptan, photoinitiator, thixotropic agent, stabilizer and colorant;The mass percentage of the acrylate resin prepolymer is 30.0%-70.0%, the mass percentage of the polyurethane resin is 10.0%-55.0%, the mass percentage of the macromolecular sulfur is 0.5%-5.0%, the mass percentage of the photoinitiator is 1.0%-10.0%, the mass percentage of the thixotropic agent is 0%-5.0%, the mass percentage of the stabilizer is 0%-0.1%, and the mass percentage of the colorant is 0%-0.1%. The ultraviolet light curing dust capturing adhesive of the application can be quickly cured under ultraviolet irradiation, has high surface polarity, low precipitation and good aging resistance. Although the ultraviolet light curing dust capturing adhesive can fix dust, it still has problems such as high haze (affecting optical light transmission), volatile residue during curing process (small molecules in resin or diluent are easily volatile under ultraviolet irradiation, adhere to the surface of the sensor to form oil stains, and cause permanent imaging bad points), and high adhesive strength (precise parts are easily damaged during maintenance), which cannot meet the special requirements of low haze, low curing volatilization, weak adhesion and temperature change resistance inside the camera. SUMMARY

[0004] To solve the above technical problems, the purpose of the present application is to provide an epoxy acrylate modified ultraviolet light curing dust capturing adhesive suitable for the inside of a camera.

[0005] In order to achieve the above-mentioned purpose, the present application provides an epoxy acrylate modified UV-curable dust capturing adhesive suitable for inside of a camera, comprising the following raw material components by weight fraction: highly reactive low viscosity epoxy acrylate resin 30.0-40.0 parts; low Tg low volatile polycaprolactone modified polyurethane acrylate 18.0-25.0 parts; high light transmission low volatile reactive diluent 20.0-30.0 parts; low migration composite photoinitiator 2.5-4.0 parts; camera special functional additive 1.8-5.2 parts; The high light transmission low volatile reactive diluent is a mixture of ethoxylated ethoxy acrylate and tripropylene glycol diacrylate in a mass ratio of 1.2-1.8:1.

[0006] Optimally, the low Tg low volatile polycaprolactone modified polyurethane acrylate has a glass transition temperature ≤-15℃ and a free isocyanate content ≤0.01%.

[0007] Further, the low Tg low volatile polycaprolactone modified polyurethane acrylate is synthesized by reaction of polycaprolactone diol, isophorone diisocyanate and hydroxyethyl acrylate in a molar ratio of 1:1.05-1.2:0.95-1.1, with a capping rate ≥99%, volatile matter ≤2mg / m² during curing process, and free isocyanate ≤0.01%.

[0008] Optimally, the highly reactive low viscosity epoxy acrylate resin is a devolatilized bisphenol A type epoxy acrylate with an epoxy value of 0.55-0.65 eq / 100g, a monomer content ≤0.1%, an epoxy acrylate resin double bond conversion rate ≥98%, and a 180° peel strength after curing of 0.3-0.8 N / cm.

[0009] Optimally, the low migration composite photoinitiator is a mixture of 2-hydroxy-2-methyl-1-phenyl-1-propanone and 2,4,6-trimethylbenzoyl-diphenyl phosphine oxide, with a weight fraction ratio of 1.8-2.8:0.7-1.2.

[0010] Optimally, the camera special functional additive includes anti-fogging agent with a boiling point ≥350℃ 0.3-0.8 parts, low volatile thixotropic agent 1.0-2.0 parts, hindered amine type light stabilizer with a boiling point ≥380℃ 0.5-1.0 parts, hindered phenolic antioxidant with a boiling point ≥450℃ 0.05-0.15 parts, and low volatile adsorptive dust-free additive 0.5-1.2 parts; the dust-free additive is a silane type adsorptive coupling agent.

[0011] Further, each component of the camera-specific functional aid is filtered through a 0.2 μm filter, and the volatile matter during the curing process is ≤0.5 mg / m 2 .

[0012] The purpose of the present application is to provide a preparation method of the above-mentioned epoxy acrylate modified UV-curable dust capturing adhesive for the inside of a camera, comprising the following steps: (a) In a Class 100 clean room, under the protection of inert gas, mix the high-reactivity low-viscosity epoxy acrylate resin with the low-Tg low-volatile polycaprolactone modified polyurethane acrylate at 40-45℃, and stir; (b) Add the high-transmittance low-volatile active diluent and stir for 15-20 min, then add the low-migration composite photoinitiator, stir at 500-600 r / min for 35-45 min, and monitor the volatile matter of the system through headspace chromatography ≤3 mg / m 2 , control the viscosity 800-1200 mPa•s; (c) Reduce to 20-25℃, add the camera-specific functional aid, and disperse at 1000-1200 r / min for 50-60 min, while vacuum degassing at ≤25℃, vacuum degree -0.095 MPa; (d) Filter through 0.5 μm and 0.2 μm filters in sequence, and package in a Class 100 clean environment.

[0013] The present application is suitable for epoxy acrylate modified UV-curable dust capturing adhesive for the inside of a camera. By using high-reactivity low-viscosity epoxy acrylate resin, low-Tg low-volatile polycaprolactone modified polyurethane acrylate, high-transmittance low-volatile active diluent, low-migration composite photoinitiator, and camera-specific functional aid, etc., the cured product has low volatile matter and zero sensor contamination: during UV curing (365 nm, energy 800-1000 mJ / cm 2 ), volatile matter ≤5 mg / m² (tested by GB / T 37884-2019 "Determination of the emission of volatile organic compounds - Bag method", total volatile matter captured after curing ≤5 μg), no small molecules adhere to the surface of the image sensor, avoiding oil-stained imaging bad points; Excellent optical compatibility: after curing, the visible light transmittance is ≥92%, the haze is ≤0.3%, the yellowing index is ≤0.5%, the infrared transmittance in the range of 800-1100 nm is ≥90%, and it does not interfere with imaging and infrared focusing; Wide temperature range stability: stable elastic modulus (100-300 MPa) in the temperature range of -40℃ to 85℃, no cracking and no dust falling after 1000 times of high-low temperature cycle, meeting the requirements of vehicle-mounted and outdoor scenes; Adapt to the precise operation: dispensing viscosity 800-1200 mPa·s, adapt to 0.1-0.3mm needle; 180° peel strength 0.3-0.8N / cm, repair without component damage, and no glue residue after peeling. DETAILED DESCRIPTION

[0014] The application is suitable for an epoxy acrylate modified ultraviolet light curing dust catching adhesive inside a camera, which comprises the following raw material components by weight: high reactivity low viscosity epoxy acrylate resin 30.0~40.0 parts; low Tg low volatile polycaprolactone modified polyurethane acrylate 18.0-25.0 parts; high light transmission low volatile active diluent 20.0-30.0 parts; low migration composite photoinitiator 2.5-4.0 parts; camera special functional additives 1.8-5.2 parts; the high light transmission low volatile active diluent is a mixture of ethoxylated ethoxy acrylate (EOEOEA, boiling point 285℃) and tripropylene glycol diacrylate (TPGDA, boiling point 310℃) in a mass ratio of 1.2~1.8:1 (the system viscosity of the mixture is controlled at 800-1200 mPa·s (adapt to dispensing), and the total volatile matter during the curing process is ≤3mg / m 2 (Through thermal gravimetric analysis TGA test, mass loss rate ≤0.001% within 30s of 365nm ultraviolet light irradiation). By using high reactivity low viscosity epoxy acrylate resin, low Tg low volatile polycaprolactone modified polyurethane acrylate, high light transmission low volatile active diluent, low migration composite photoinitiator and camera special functional additives, the cured low volatile, zero sensor pollution can be achieved: during the ultraviolet light curing process (365nm, energy 800-1000mJ / cm 2 ), volatile matter ≤5mg / m² (tested by GB / T 37884-2019 "Determination of the emission of volatile organic compounds-purge method", total volatile matter captured after curing ≤5μg), no small molecules adhere to the image sensor surface, avoiding the appearance of oil stain type imaging bad points; excellent optical compatibility: visible light transmittance ≥92% after curing, haze ≤0.3%, yellowing index ≤0.5%, infrared transmittance ≥90% at 800-1100nm, without interfering with imaging and infrared focusing; wide temperature range stability: elastic modulus is stable (100-300MPa) within -40℃~85℃ temperature range, no cracking and no dust falling after 1000 times of high and low temperature cycles, meeting the requirements of vehicle-mounted and outdoor scenes; adapt to the precise operation: dispensing viscosity 800-1200 mPa·s, adapt to 0.1-0.3mm needle; 180° peel strength 0.3-0.8N / cm, repair without component damage, and no glue residue after peeling.

[0015] The low-Tg low-volatility polycaprolactone-modified polyurethane acrylate has a glass transition temperature ≤-15℃ and a free isocyanate content ≤0.01%. The low-Tg low-volatility polycaprolactone-modified polyurethane acrylate is synthesized by reacting polycaprolactone diol (number average molecular weight 2000-3000), isophorone diisocyanate (IPDI) and hydroxyethyl acrylate (HEA) in a molar ratio of 1:1.05-1.2:0.95-1.1, with a capping rate ≥99%, volatile matter ≤2mg / m2 during the curing process, free isocyanate ≤0.01%, avoiding the reaction of hydroxyl and isocyanate to generate small molecule volatile matter (such as CO2 or alcohol) during curing, Tg ≤-15℃, excellent temperature stability, and haze ≤0.2% after curing. The high-reactivity low-viscosity epoxy acrylate resin is a devolatilized bisphenol A type epoxy acrylate with an epoxy value of 0.55-0.65 eq / 100g, a monomer content ≤0.1%, an epoxy acrylate resin double bond conversion rate ≥98%, and a 180° peel strength of 0.3~0.8N / cm after curing. The low-migration composite photoinitiator is a mixture of 2-hydroxy-2-methyl-1-phenyl-1-propanone and 2,4,6-trimethylbenzoyl-diphenyl phosphine oxide, with a weight ratio of 1.8~2.8:0.7~1.2. The camera-specific functional additive includes an anti-haze agent with a boiling point ≥350℃ of 0.3~0.8 parts, a low-volatility thixotropic agent of 1.0~2.0 parts, a hindered amine light stabilizer with a boiling point ≥380℃ of 0.5~1.0 parts, a hindered phenolic antioxidant with a boiling point ≥450℃ of 0.05-0.15 parts, and a low-volatility adsorption type dust-free additive of 0.5~1.2 parts; the dust-free additive is a silane adsorption type coupling agent, preferably a γ-aminopropyl triethoxysilane modified derivative, with volatile matter ≤2mg / m 2 , compatibility with resin and diluent ≥95%, without affecting the double bond conversion rate of the curing system, and can agglomerate dust particles inside the camera through physical adsorption, avoiding dust from escaping to the lens or the surface of the light-sensitive element. Each component of the camera-specific functional additive is filtered through a 0.2μm filter, with volatile matter ≤0.5mg / m 2 .

[0016] The above method for preparing an epoxy acrylate-modified ultraviolet light-cured dust-catching adhesive for use inside a camera includes the following steps: (a) mixing the high-reactivity low-viscosity epoxy acrylate resin and the low-Tg low-volatility polycaprolactone-modified polyurethane acrylate at 40~45℃ under inert gas protection in a Class 100 cleanroom, stirring; (b) adding the high-transmittance low-volatility active diluent and stirring for 15~20min, then adding the low-migration composite photoinitiator and stirring at 500~600r / min for 35-45min, monitoring the volatile matter of the system through headspace chromatography ≤3mg / m 2, control the viscosity 800-1200 mPa s; (c) drop to 20-25 DEG C, add the camera special function adjuvant, at 1000~1200 r / min high speed dispersion 50~60 min, while in ≤25 DEG C, vacuum degree-0.095 MPa under vacuum defoaming; (d) through 0.5 μm, 0.2 μm filter screen filtration, in Class 100 level dust-free environment under dispensing.

[0017] For those skilled in the technical field, the following will be combined with examples, the technical solutions in the embodiments of the present application are described clearly and completely, obviously, the described embodiments are only a part of the embodiments of the present application, not all. Based on the embodiments in the present application, all other embodiments obtained by equivalent changes and modifications made by those skilled in the art should belong to the scope of protection of the present application. Example 1

[0018] The present embodiment provides an epoxy acrylate modified ultraviolet light curing dust catching adhesive suitable for the inside of a camera and a preparation method thereof, specifically as follows: High reactivity low viscosity epoxy acrylate resin 35.0 kg (brand EA-600), low Tg low volatile polycaprolactone modified polyurethane acrylate 22.0 kg (made according to the following method), ethoxylated ethoxy acrylate (EOEOEA) 15.0 kg, tripropylene glycol diacrylate (TPGDA) 10.0 kg, 1173 (2-hydroxy-2-methyl-1-phenyl-1-propanone) 2.2 kg, TPO (2,4,6-trimethylbenzoyl-diphenyl phosphine oxide) 0.8 kg, anti-fogging agent (brand AF-350) 0.5 kg, low volatile thixotropic agent (brand TH-200) 1.5 kg, HALS 770 (hindered amine light stabilizer) 0.8 kg, 1010 (antioxidant) 0.1 kg, dust-free adjuvant (γ-aminopropyl triethoxysilane modified derivative, Si-AD-01) 1.1 kg; The preparation method of the low Tg low volatile polycaprolactone modified polyurethane acrylate is as follows: a. Molar ratio of raw materials: poly (caprolactone) diol (number average molecular weight 2500), isophorone diisocyanate and hydroxyethyl acrylate were weighed according to the proportion (poly (caprolactone) diol: isophorone diisocyanate: hydroxyethyl acrylate was 1:1.1:1.0), and mixed uniformly; b. Synthesis process: under nitrogen protection, react at 45 DEG C for 3 h, and keep warm at 60 DEG C for 1 h, the actual measured end-capping rate is 99.5%, the free isocyanate content is 0.008%, and the volatile matter in the curing process is 1.8 mg / m 2 , the glass transition temperature (Tg) is-22 DEG C.

[0019] The preparation method of the epoxy acrylate modified UV-curable dust capturing adhesive suitable for the inside of a camera is as follows: (a) mixing the high-reactivity low-viscosity epoxy acrylate resin and the low-Tg low-volatility polycaprolactone modified polyurethane acrylate at 40-45°C under inert gas protection in a Class 100 clean room, stirring for 25-35 min, and then cooling to 25-28°C; (b) adding high-transmittance low-volatility active diluent, stirring for 15-20 min, then adding the low-migration composite photoinitiator, stirring at 500-600 r / min for 35-45 min, and monitoring the volatile matter of the system by headspace chromatography to be ≤3 mg / m 2 , and controlling the viscosity to be 800-1200 mPa•s; (c) cooling to 20-25°C, adding camera-specific functional additives, and high-speed dispersing at 1000-1200 r / min for 50-60 min, while vacuum degassing at ≤25°C and a vacuum degree of -0.095 MPa; (d) filtering successively through 0.5 μm and 0.2 μm polytetrafluoroethylene screens, dispensing in a Class 100 clean environment, and the volatile matter of the finished product during 365 nm UV curing is ≤5 mg / m 2 .

[0020] Performance test (specific for mobile phone camera): Curing and volatilization performance: 365 nm UV curing for 25 s (energy 900 mJ / cm²), volatile matter 3.2 mg / m² (HS-GC test), and no oil stain residue on the sensor surface (optical microscope observation, 400 times without foreign matter); Optical performance: light transmittance (400-700 nm) 93.5%, haze 0.22%, and yellowing index 0.4; Temperature change stability: after 1000 cycles of -40°C to 85°C, the adhesive layer has no cracking, and the dust fixation rate is 100%. Example 2

[0021] This example provides an epoxy acrylate modified UV-curable dust capturing adhesive suitable for the inside of a camera and a preparation method thereof, which is basically the same as in Example 1, except that: Highly reactive low viscosity epoxy acrylate resin 32.0 kg, low Tg low volatile polycaprolactone modified polyurethane acrylate 24.0 kg, ethoxylated ethoxy acrylate (EOEOEA) 16.0 kg, tripropylene glycol diacrylate (TPGDA) 10.0 kg, 1173 (2-hydroxy-2-methyl-1-phenyl-1-propanone) 2.0 kg, TPO (2,4,6-trimethylbenzoyl-diphenyl phosphine oxide) 1.0 kg, anti-haze agent 0.6 kg, low volatile thixotropic agent 1.8 kg, HALS 770 (hindered amine light stabilizer) 1.0 kg, 1010 (antioxidant) 0.1 kg, dust-free auxiliary agent 1.2 kg.

[0022] Performance test (special for vehicle-mounted camera): Curing volatilization performance: 365 nm ultraviolet curing for 28 s (energy 950 mJ / cm²), volatiles 4.5 mg / m², sensor surface oil stain residual amount ≤0.1 μg / cm 2 (X-ray fluorescence spectrum test); Optical performance: light transmittance (400-700 nm) 92.8%, haze 0.28%, infrared light transmittance 91.2%; Wet heat resistance: after being placed at 85°C / 85% RH for 500 h, the glue layer has no hydrolysis, and the dust fixation rate is 100%. Example 3

[0023] The present embodiment provides an epoxy acrylate modified ultraviolet curing dust catching adhesive suitable for the inside of a camera and a preparation method thereof, which is basically the same as that in Example 1, except that: Highly reactive low viscosity epoxy acrylate resin 38.0 kg, low Tg low volatile polycaprolactone modified polyurethane acrylate 20.0 kg, ethoxylated ethoxy acrylate (EOEOEA) 14.0 kg, tripropylene glycol diacrylate (TPGDA) 12.0 kg, 1173 (2-hydroxy-2-methyl-1-phenyl-1-propanone) 2.5 kg, TPO (2,4,6-trimethylbenzoyl-diphenyl phosphine oxide) 0.7 kg, anti-haze agent 0.4 kg, low volatile thixotropic agent 1.2 kg, HALS 770 (hindered amine light stabilizer) 0.6 kg, 1010 (antioxidant) 0.8 kg, dust-free auxiliary agent 0.6 kg.

[0024] Performance test (special for security monitoring camera): Curing volatilization performance: 365 nm ultraviolet curing for 22 s (energy 850 mJ / cm²), volatiles 2.8 mg / m², no bad points in sensor imaging after curing (resolution test, 1080P image quality is normal); Optical performance: transmittance (400-700nm) 94.1%, haze 0.18%; Long-term stability: After 6 months of outdoor exposure, the adhesive layer showed no signs of aging or yellowing, and the dust fixation rate was over 98%. Example 4

[0025] This embodiment provides an epoxy acrylate modified UV-curable dust-collecting adhesive suitable for use inside a camera and its preparation method. It is basically the same as that in Example 1, except that: Highly reactive, low-viscosity epoxy acrylate resin 30.0 kg, low-Tg, low-volatile polycaprolactone-modified polyurethane acrylate 25.0 kg, ethoxylated ethoxyacrylate (EOEOEA) 16.0 kg, tripropylene glycol diacrylate (TPGDA) 9.0 kg, 1173 (2-hydroxy-2-methyl-1-phenyl-1-propanone) 2.3 kg, TPO (2,4,6-trimethylbenzoyl-diphenylphosphine oxide) 0.9 kg, anti-hazing agent 0.7 kg, low-volatile thixotropic agent 1.8 kg, HALS 770 (hindered amine light stabilizer) 1.0 kg, 1010 (antioxidant) 0.1 kg, dust-free additive 1.0 kg.

[0026] Performance testing (specifically for foldable phone cameras, focusing on flexibility): Curing and volatile properties: Cured with 365nm UV light for 26s (energy 920mJ / cm²), volatile matter 3.8mg / m², sensor free of oil stains; Core compatibility: Bending performance (180° bend, 2mm radius, 1000 cycles) with no cracking of the adhesive layer; elongation at break of 98% (higher than the ordinary embodiment); Optical performance: transmittance (400-700nm) 92.6%, haze 0.25%. Example 5

[0027] This embodiment provides an epoxy acrylate modified UV-curable dust-collecting adhesive suitable for use inside a camera and its preparation method. It is basically the same as that in Example 1, except that: Highly reactive, low-viscosity epoxy acrylate resin 33.0 kg, low-Tg, low-volatile polycaprolactone-modified polyurethane acrylate 22.0 kg, ethoxylated ethoxyacrylate (EOEOEA) 15.0 kg, tripropylene glycol diacrylate (TPGDA) 10.0 kg, 1173 (2-hydroxy-2-methyl-1-phenyl-1-propanone) 2.1 kg, TPO (2,4,6-trimethylbenzoyl-diphenylphosphine oxide) 1.0 kg, anti-hazing agent 0.6 kg, low-volatile thixotropic agent 1.5 kg, HALS 770 (hindered amine light stabilizer) 0.8 kg, 1010 (antioxidant) 0.1 kg, dust-free additive 0.5 kg.

[0028] Performance testing (specifically for automotive LiDAR cameras, focusing on infrared light transmission): Curing and volatile properties: Cured under 365nm UV light for 27s (energy 940mJ / cm²), volatile matter 4.2mg / m²; Core compatibility: 905nm infrared transmittance 93.5% (approximately 90% in typical embodiments); no cracking after 1500 cycles at -40℃ to 85℃; Optical performance: Visible light transmittance 93.1%, haze 0.23%. Example 6

[0029] This embodiment provides an epoxy acrylate modified UV-curable dust-collecting adhesive suitable for use inside a camera and its preparation method. It is basically the same as that in Example 1, except that: Highly reactive, low-viscosity epoxy acrylate resin 31.0 kg, low-Tg, low-volatile polycaprolactone-modified polyurethane acrylate 19.0 kg, ethoxylated ethoxyacrylate (EOEOEA) 18.0 kg, tripropylene glycol diacrylate (TPGDA) 10.0 kg, 1173 (2-hydroxy-2-methyl-1-phenyl-1-propanone) 2.4 kg, TPO (2,4,6-trimethylbenzoyl-diphenylphosphine oxide) 0.8 kg, anti-hazing agent 0.5 kg, low-volatile thixotropic agent 1.2 kg, HALS 770 (hindered amine light stabilizer) 0.9 kg, 1010 (antioxidant) 0.1 kg, dust-free additive: 1.0 kg.

[0030] Performance testing (specifically for miniature security cameras, focusing on low-viscosity adhesive): Curing and volatile properties: Cured under 365nm UV light for 23s (energy 880mJ / cm²), volatile matter 3.0mg / m²; Core compatibility: Dispensing viscosity 650 mPa・s (compatible with 0.08 mm needle); uniform coating even in minute spaces (φ2 mm × 1 mm); Optical performance: light transmittance 92.8%, haze 0.27%. Example 7

[0031] This embodiment provides an epoxy acrylate modified UV-curable dust-collecting adhesive suitable for use inside a camera and its preparation method. It is basically the same as that in Example 1, except that: Highly reactive, low-viscosity epoxy acrylate resin 37.0 kg, low-Tg, low-volatile polycaprolactone-modified polyurethane acrylate 20.0 kg, ethoxylated ethoxyacrylate (EOEOEA) 14.0 kg, tripropylene glycol diacrylate (TPGDA) 10.0 kg, 1173 (2-hydroxy-2-methyl-1-phenyl-1-propanone) 2.6 kg, TPO (2,4,6-trimethylbenzoyl-diphenylphosphine oxide) 0.7 kg, anti-hazing agent 0.5 kg, low-volatile thixotropic agent 1.6 kg, HALS 770 (hindered amine light stabilizer) 0.8 kg, 1010 (antioxidant) 0.1 kg, dust-free additive 0.8 kg.

[0032] Performance testing (specifically for drone aerial photography cameras, with an emphasis on weather resistance): Curing and volatile properties: Cured with 365nm UV light for 24s (energy 860mJ / cm²), volatile matter 2.9mg / m²; Core compatibility: After 2000 hours of aging, the yellowing index of the UVB-313 lamp is 0.8 (compared to 1.5 in the general example); no cracking occurs after 1000 cycles at -50℃ to 90℃. Optical performance: light transmittance 93.7%, haze 0.21%. Example 8

[0033] This embodiment provides an epoxy acrylate modified UV-curable dust-collecting adhesive suitable for use inside a camera and its preparation method. It is basically the same as that in Example 1, except that: Highly reactive, low-viscosity epoxy acrylate resin 34.0 kg, low-Tg, low-volatile polycaprolactone-modified polyurethane acrylate 21.0 kg, ethoxylated ethoxyacrylate (EOEOEA) 16.0 kg, tripropylene glycol diacrylate (TPGDA) 9.0 kg, 1173 (2-hydroxy-2-methyl-1-phenyl-1-propanone) 2.2 kg, TPO (2,4,6-trimethylbenzoyl-diphenylphosphine oxide) 0.9 kg, anti-hazing agent 0.6 kg, low-volatile thixotropic agent 1.4 kg, HALS 770 (hindered amine light stabilizer) 0.8 kg, 1010 (antioxidant) 0.1 kg, dust-free additive 1.2 kg (all raw materials are medical grade or biocompatible).

[0034] Performance testing (specifically for medical endoscope cameras, with an emphasis on biocompatibility): Curing and volatile properties: Cured under 365nm UV light for 28s (energy 960mJ / cm²), volatile matter 4.1mg / m²; Core compatibility: Cytotoxicity (ISO 10993-5): Non-cytotoxic; Disinfection resistance (no loss of adhesion after 500 wipings with 75% ethanol); Optical performance: light transmittance 93.3%, haze 0.24%.

[0035] Comparative Example 1 This example provides a dust-catching adhesive that is basically the same as that in Example 1, except that: ordinary acrylate resin (non-highly reactive type, double bond conversion rate 85%, Baojun Chemical 2412) is used instead of highly reactive low viscosity epoxy acrylate resin; and uncapped ordinary polyurethane acrylate (free isocyanate 0.1%) is used instead of low Tg low volatile polycaprolactone modified polyurethane acrylate.

[0036] Performance testing: Curing and volatile properties: After curing with 365nm ultraviolet light for 30s, the volatile matter content was 18.5mg / m², and obvious oil stains appeared on the sensor surface, resulting in 3 dead pixels in the image. Optical performance: Light transmittance 88.2%, haze 0.85% (far exceeding ≤0.3%); Stability: After 500 cycles at -40℃ to 85℃, the adhesive layer cracks and the dust shedding rate is 30%.

[0037] Comparative Example 2 This example provides a dust-catching adhesive that is basically the same as that in Example 1, except that the high-transmittance, low-volatility active diluent (a mixture of EOEOEA and TPGDA) is replaced with a common diluent, styrene (boiling point 145°C).

[0038] Performance testing: Curing and volatile properties: After curing with 365nm ultraviolet light for 25s, the volatile matter content is 25.3mg / m², and white crystals (styrene volatilization residue) form on the sensor surface, resulting in blurred imaging; Optical properties: Light transmittance 85.7% (yellowing due to styrene), haze 1.2%; Safety: Styrene residue is 120 ppm (far exceeding ≤10 ppm), and has an irritating odor.

[0039] Comparative Example 3 This example provides a dust-catching adhesive that is essentially the same as that in Example 1, except that the low-migration composite photoinitiator (a mixture of 2-hydroxy-2-methyl-1-phenyl-1-propanone and 2,4,6-trimethylbenzoyl-diphenylphosphine oxide, with a total mass equal to that of the single photoinitiator 1173) in Example 1 is replaced with a single photoinitiator 1173 (without TPO compound).

[0040] Performance testing: Curing and volatile properties: Curing with 365nm UV light for 45s (slow curing), volatile matter 7.8mg / m² (1173 residual volatilization), light yellow residue on sensor surface; Curing efficiency: Incomplete deep curing (adhesive layer thickness 0.2mm, uncured rate of the bottom layer 15%), adhesion level 3 (Level 1 in Example 1). Stability: Yellowing index after aging is 2.3.

[0041] Comparative Example 4 This example provides a dust-catching adhesive that is basically the same as that in Example 1, except that the low Tg polycaprolactone-modified polyurethane acrylate was not end-capped (end-capping rate 80%, free isocyanate 0.05%).

[0042] Performance testing: Curing and volatile properties: After curing with 365nm UV light for 25s, the volatile matter content is 9.2mg / m³. 2 (The free isocyanate reacts to generate CO2, which then volatilizes), and tiny bubbles appear on the sensor surface; Temperature stability: After 800 cycles at -40℃ to 85℃, microcracks appeared in the adhesive layer, and the dust fixation rate dropped to 75%. Moisture and heat resistance: After being placed at 85℃ / 85% RH for 300 hours, the adhesive layer hydrolyzes and becomes sticky, losing its dust-collecting ability.

[0043] Comparative Example 5 This example provides a dust-catching adhesive that is basically the same as that in Example 1, except that it does not use anti-fogging agents, low-volatility thixotropic agents, or HALS 770.

[0044] Performance testing: Optical performance: Haze 1.5%, camera image shows halo; Operational performance: Dispensing viscosity is 2100 mPa•s, which is not compatible with 0.2 mm needles, resulting in uneven coating; Weather resistance: After 500 hours of UV aging, the yellowing index is 3.8, the adhesive layer becomes brittle, and the dust shedding rate is 45%.

[0045] Comparative Example 6 This example provides a dust-catching adhesive, which is basically the same as that in Example 1, except that: 31.0 kg of highly reactive, low-viscosity epoxy acrylate resin, 19.0 kg of low-Tg, low-volatile polycaprolactone-modified polyurethane acrylate, 20.0 kg of ethoxylated ethoxyacrylate (EOEOEA), 6.0 kg of tripropylene glycol diacrylate (TPGDA) (EOEOEA to TPGDA mass ratio approximately 3.3:1), 2.4 kg of 1173 (2-hydroxy-2-methyl-1-phenyl-1-propanone), 0.8 kg of TPO (2,4,6-trimethylbenzoyl-diphenylphosphine oxide), 0.5 kg of anti-hazing agent, 1.2 kg of low-volatile thixotropic agent, 0.9 kg of HALS 770 (hindered amine light stabilizer), 0.1 kg of 1010 (antioxidant), and 1.0 kg of dust-free additive.

[0046] Performance testing (specifically for miniature security cameras, focusing on low-viscosity adhesive): Curing and volatile properties: Cured under 365nm UV light for 23s (energy 880mJ / cm²), volatile matter 12.5mg / m²; Core compatibility: Dispensing viscosity 230 Pa・s (compatible with 0.08 mm needle); uniform coating even in minute spaces (φ2 mm × 1 mm); Optical performance: 87% transmittance, 0.95% haze.

[0047] The above description is merely a preferred embodiment of the present invention and is not intended to limit the scope of protection of the present invention. At the same time, those skilled in the art should understand and implement the above description. Therefore, any equivalent changes or modifications made without departing from the concept disclosed in the present invention should be covered within the scope of protection of the present invention.

Claims

1. An epoxy acrylate modified UV-curable dust-collecting adhesive suitable for use inside cameras, characterized in that, The raw material components include the following parts by weight: 30.0~40.0 parts of highly reactive, low-viscosity epoxy acrylate resin; 18.0-25.0 parts of low-Tg, low-volatile polycaprolactone-modified polyurethane acrylate; 20.0-30.0 parts of high-transmittance, low-volatility reactive diluent; 2.5-4.0 parts of low-migration composite photoinitiator; Camera-specific functional additives: 1.8-5.2 parts; The high-transmittance, low-volatility reactive diluent is a mixture of ethoxylated ethoxyacrylate and tripropylene glycol diacrylate in a mass ratio of 1.2 to 1.8:

1.

2. The epoxy acrylate modified UV-curable dust-collecting adhesive suitable for use inside a camera according to claim 1, characterized in that: The low-Tg, low-volatile polycaprolactone-modified polyurethane acrylate has a glass transition temperature ≤ -15℃ and a free isocyanate content ≤ 0.01%.

3. The epoxy acrylate modified UV-curable dust-collecting adhesive suitable for use inside a camera according to claim 2, characterized in that: The low-Tg, low-volatile polycaprolactone-modified polyurethane acrylate is synthesized by reacting polycaprolactone diol, isophorone diisocyanate and hydroxyethyl acrylate in a molar ratio of 1:1.05-1.2:0.95-1.1, with an end-capping rate ≥99%, volatile matter during curing ≤2mg / m², and free isocyanate ≤0.01%.

4. The epoxy acrylate modified UV-curable dust-collecting adhesive for use inside a camera according to claim 1, characterized in that: The highly reactive, low-viscosity epoxy acrylate resin is a devolatilized bisphenol A type epoxy acrylate with an epoxy value of 0.55-0.65 eq / 100g, a monomer content of ≤0.1%, a double bond conversion rate of ≥98%, and a peel strength of 0.3~0.8 N / cm at 180° after curing.

5. The epoxy acrylate modified UV-curable dust-collecting adhesive for use inside a camera according to claim 1, characterized in that: The low-migration composite photoinitiator is composed of a mixture of 2-hydroxy-2-methyl-1-phenyl-1-propanone and 2,4,6-trimethylbenzoyl-diphenylphosphine oxide in a weight ratio of 1.8~2.8:0.7~1.

2.

6. The epoxy acrylate modified UV-curable dust-collecting adhesive for use inside a camera according to claim 1, characterized in that: The camera-specific functional additives include 0.3-0.8 parts of an anti-hazing agent with a boiling point ≥350℃, 1.0-2.0 parts of a low-volatility thixotropic agent, 0.5-1.0 parts of a hindered amine light stabilizer with a boiling point ≥380℃, 0.05-0.15 parts of a hindered phenolic antioxidant with a boiling point ≥450℃, and 0.5-1.2 parts of a low-volatility adsorption-type dust-free additive; the dust-free additive is a silane-based adsorption coupling agent.

7. The epoxy acrylate modified UV-curable dust-collecting adhesive for use inside a camera according to claim 6, characterized in that: All components of the camera-specific functional additive are filtered through a 0.2μm filter, and the volatile matter content during the curing process is ≤0.5mg / m³. 2 .

8. The method for preparing the epoxy acrylate modified UV-curable dust-collecting adhesive for use inside a camera as described in any one of claims 1 to 7, characterized in that, Includes the following steps: (a) In a Class 100 cleanroom under inert gas protection, the highly reactive low-viscosity epoxy acrylate resin and the low-Tg, low-volatile polycaprolactone-modified polyurethane acrylate are mixed at 40-45°C and stirred. (b) Add the high-transmittance, low-volatility active diluent and stir for 15-20 min, then add the low-migration composite photoinitiator and stir at 500-600 r / min for 35-45 min. Monitor the volatile matter content of the system using headspace chromatography; the result should be ≤3 mg / m³. 2 Control the viscosity to 800-1200 mPa•s; (c) Cool to 20-25℃, add the camera-specific functional additive, disperse at high speed of 1000~1200r / min for 50~60min, and simultaneously degas under vacuum at ≤25℃ and vacuum degree -0.095MPa; (d) The product is filtered through 0.5μm and 0.2μm filters in sequence and then packaged in a Class 100 cleanroom environment.