CN112055431B

CN112055431B - Silica gel cold-bonding process and silica gel heating sheet prepared by same

Info

Publication number: CN112055431B
Application number: CN202010964676.8A
Authority: CN
Inventors: 姜喜军; 邵敬彪
Original assignee: Jiaxing Danting New Material Co ltd
Current assignee: Zhejiang Classic Car Clothing Co ltd; Zhejiang Danting New Material Co ltd
Priority date: 2020-09-14
Filing date: 2020-09-14
Publication date: 2021-06-29
Anticipated expiration: 2040-09-14
Also published as: CN112055431A

Abstract

The application relates to the technical field of silica gel heat seal processing, in particular to a silica gel cold bonding process and a silica gel heating sheet prepared by the process, and the silica gel cold bonding process comprises the following steps of 1: coating silica gel on one surface of the heating film by using a glue spreader; step 2: compounding the cooked rubber on the side, coated with the silica gel, of the heating film by adopting a cold laminating machine, wherein the laminating temperature is as follows: 30 ℃. + -. 2 ℃, pressure: 1000N; and step 3: coating silica gel on the other surface of the heating film in a scraping way; and 4, step 4: compounding the cooked rubber on the side, coated with the silica gel, of the heating film by adopting a cold laminating machine, wherein the laminating temperature is as follows: 30 ℃. + -. 2 ℃, pressure: 1000N, obtaining the target product. The process has the effects of no harm to the environment, no waste gas, environmental protection, energy conservation, no toxicity, no harm and high processing efficiency. A silica gel heating plate comprises a heating film layer as a core layer, wherein both sides of the heating film layer are adhered with adhesive layers; the adhesive layer is adhered with a silica gel layer; the adhesive layer is electronic liquid silica gel or heat-conducting silica gel; has the effect of good use safety performance.

Description

Silica gel cold-bonding process and silica gel heating sheet prepared by same

Technical Field

The application relates to the technical field of silica gel heat seal processing, in particular to a silica gel cold bonding process and a silica gel heating sheet prepared by the process.

Background

Because the silica gel heating plate has strong insulativity and corrosion resistance and can be customized according to the requirements of customers, more and more silica gel heating plates are applied in the industries of automobiles, high-speed rails and the like. The existing processing technology of the silica gel heating plate comprises the following steps: the operation is carried out by adopting a vulcanizing press, the high temperature during high-temperature vulcanization is 160-220 ℃, and the pressure of hot pressing is 2 x 10⁴N; the adhesive layer is made of high-temperature-resistant adhesive and can resist the temperature of 300 ℃; and (3) a pressing mode: and pressing a flat plate of a vulcanizing press.

The prior art has the following disadvantages: the method has the advantages that the method has destructive effect on the silica gel and material molecules in the heating film, so that the heating performance is reduced to some extent, the reduction rule can be followed, the index range is expanded during design, and the high rejection rate is easy to occur in the pressing process. In addition, the heating sheet is subjected to plane pressing during pressing, the size of the heating sheet is limited by the size of a heating platform of a vulcanizing press, and if sectional pressing is adopted, the problems of overvoltage or undervoltage are easily caused in a combining section, and the phenomena of damage or bubbles are easily caused; meanwhile, the pressure maintaining time and the cooling time are required during the pressing. During hot pressing, the requirements on equipment are very high, the temperature is uniform, and the pressure is uniform, so that the debugging requirements on the equipment at the early stage are very high.

In conclusion, the high-temperature vulcanization pressing in the prior art has high requirements on places and personnel, and also has certain requirements on the waste gas treatment of the environment.

Disclosure of Invention

In order to solve the problems that the prior art has higher requirements on fields and personnel and also has certain requirements on the treatment of waste gas of the environment, the first aim of the application is to provide a silica gel cold-bonding process, and the process has the effects of no harm to the environment, no waste gas, environmental protection, energy conservation, no toxicity, no harm and high processing efficiency.

The second purpose of the invention is to provide a silica gel heating plate prepared by using a silica gel cold-bonding process, which can be used for heating a high-speed molten iron tank, is approved by a high-speed railway management department, and has the effect of higher use safety performance.

In order to achieve the first object, the invention provides the following technical scheme: a silica gel cold-bonding process comprises the following steps:

step 1: coating silica gel on one surface of the heating film by using a glue spreader;

step 2: compounding the cooked rubber on the side, coated with the silica gel, of the heating film by adopting a cold laminating machine, wherein the laminating temperature is as follows: 30 ℃. + -. 2 ℃, pressure: 1000N;

and step 3: coating silica gel on the other surface of the heating film in a scraping way;

and 4, step 4: compounding the cooked rubber on the side, coated with the silica gel, of the heating film by adopting a cold laminating machine, wherein the laminating temperature is as follows: 30 ℃. + -. 2 ℃, pressure: 1000N, obtaining the target product.

By adopting the technical scheme, the process breaks through the prior art, the inventor improves the process under the condition of one-time accident, and the performance of the silica gel heating sheet produced by the process is similar to that of the silica gel heating sheet produced by the prior art, so that the process has the effects of no harm to the environment, no waste gas, environmental protection, energy conservation, no toxicity, no harm and high processing efficiency, is pressed by adopting a cold mounting roller, has small pressure, cannot damage the inner part of the heating sheet, is more convenient and applicable in design and has higher precision; the silica gel is uniformly coated by a glue spreader, and is pressed by a roller in a cold mounting mode, so that long-time preparation in the early stage is not needed; the cold mounting machine is adopted for pressing operation, so that the pressing speed is high, waiting is not needed, the heating piece can be used along with pressing, the length of the heating piece is not limited, and the customized processing production is facilitated.

Preferably, in the step 2, the humidity is controlled to be 60% ± 5%, and in the step 4, the humidity is controlled to be 60% ± 5%.

By adopting the technical scheme, the production efficiency of the silica gel heating plate is improved, the damage to the high molecular structure of the heating plate can not be caused, the defect that high temperature and high pressure in the traditional process have damage effects on high molecular materials is overcome, the length is not limited when the silica gel heating plate is produced by the process, and the product has better quality.

Preferably, the silica gel used in the step 1 and the step 3 is electronic liquid silica gel or heat-conducting silica gel.

By adopting the technical scheme, a good pressing effect can be achieved, the pressing temperature is low, the power consumption can be reduced, and the method is more environment-friendly; the better heat conductivity of the heating film ensures that the heat of the heating film is uniformly conducted to the cooked rubber, the integral heat dispersion is ensured, the temperature difference of each part is small, and the heating uniformity is better.

Preferably, one surface of the heating film in the step 1 is coated with silica gel in a scraping manner, wherein the silica gel thickness is 0.2-2.0 mm; and (3) coating silica gel on the other surface of the heating film in the step 3 to a thickness of 0.2-2.0 mm.

By adopting the technical scheme, the adhesive strength can be ensured, the integral peeling strength is improved, the material consumption can be reduced, and the cost is saved.

Preferably, before the step 1, the heating film is subjected to temperature control treatment, wherein the temperature is controlled to be 20 +/-2 ℃; the temperature of the silica gel between the doctor blade was controlled at 15. + -. 2 ℃.

By adopting the technical scheme, the heating film can ensure the quality of the products in the same batch; and the silica gel temperature of 15 +/-2 ℃ can ensure the fluidity of the silica gel during pressing, avoid the phenomenon of damage or bubbles and further ensure the quality of products.

Preferably, before the step 1, the heating film is subjected to temperature control treatment at 20 ℃ +/-2 ℃, and then the surface of the heating film to be coated with the silica gel is blown by using an air cavity air gun.

By adopting the technical scheme, the influence of impurity metal and dust in the air on the heating film is removed, the resistance of the heating film can be effectively controlled, the accuracy of the resistance of the heating film is ensured, the integral heating power is ensured, and the high-quality silica gel heating sheet is obtained.

Preferably, the step 4: compounding the cooked rubber on the side, coated with the silica gel, of the heating film by adopting a cold laminating machine, wherein the laminating temperature is as follows: 30 ℃. + -. 2 ℃, pressure: 1000N, after the pressing is finished, performing post-treatment to obtain a target product; the post-treatment comprises the following steps: the silica gel heating sheet after the pressing is finished firstly enters a first processing area with the temperature of 40 +/-1 ℃ for 2-3 min; then enters a second treatment area with the temperature of 20 +/-2 ℃ for 4-5 min.

By adopting the technical scheme, the internal stress among the silica gel, the heating film and the vulcanized rubber can be released, the toughness, the tensile property, the tear resistance and the aging resistance of the product are improved, and the service life and the application range of the product are prolonged.

In order to achieve the second object, the invention provides the following technical scheme:

a silica gel heating sheet prepared by a silica gel cold bonding process comprises a heating film layer as a core layer, wherein adhesive layers are bonded on two sides of the heating film layer; the adhesive layer is adhered with a silica gel layer; the adhesive layer is electronic liquid silica gel or heat-conducting silica gel; the silica gel layer is made of vulcanized rubber.

Through adopting above-mentioned technical scheme, through the adhesive layer with silica gel layer adhesion in heating film layer surface, break through prior art, realized fast, needn't wait for, along with pressfitting heating film layer and silica gel layer that the pressure was used, have green's advantage, this product is used comparatively safely, and withstand voltage breakdown performance is better, and has the advantage that generates heat evenly, heat conversion rate is high.

Preferably, the two surfaces of the hot film layer are compounded with insulating film layers; the insulating film layer is positioned between the adhesive layer and the heating film layer; the insulating film layer is a PI layer or a PET layer.

By adopting the technical scheme, the voltage breakdown resistance of the product can be improved, and the breakdown phenomenon is avoided after the voltage breakdown resistance is tested for 1 minute under the voltage withstand test of 2000V.

Preferably, the formula of the heating film layer is as follows: 20% of HDPE, 25% of metallocene linear low-density polyethylene, 30% of polypropylene, 3% of nano nickel powder, 0.2% of surfactant, 6.3% of multi-wall tubular carbon nanotube, 0.5% of graphene, 10% of nano conductive carbon black powder and 5% of PTC reinforcing agent.

By adopting the technical scheme, the heating film layer can be connected with the temperature control cabinet through the electric wire, the temperature is stabilized within the range of 70 +/-1 ℃, the product generates heat uniformly, the heat conversion rate is high, and the PTC temperature self-limiting effect is achieved.

In summary, the present application has the following advantages:

1. the process has the advantages of high speed, no need of waiting, use along with pressure and environmental protection.

2. The process adopts a cold mounting mode for roller pressing, has small pressure, can not damage the inner part of the heating sheet, is more convenient and applicable in design and has higher precision.

3. This application technology adopts electron liquid silica gel or heat conduction silica gel to pass through the even coating of coating machine, through adopting cold mounting mode roller pressfitting, need not long-time preparation in earlier stage.

4. The length of the heating plate in the process is not limited.

5. The product can be used for heating a high-speed molten iron tank, is approved by high-speed rail management departments, and has the effect of higher use safety performance.

Drawings

Fig. 1 is a schematic view of the overall structure of a silicone heating sheet in embodiment 1 of the present application.

Fig. 2 is a schematic view of the overall structure of the silica gel heating sheet in embodiment 5 of the present application.

Fig. 3 is a schematic diagram of the overall structure of the glue applicator in the present application.

Fig. 4 is a schematic structural diagram of a preheating mechanism in the glue applicator in the present application.

FIG. 5 is a schematic structural diagram of a coater mechanism and a surface impurity removal mechanism according to the present application.

Fig. 6 is a schematic view of the structure of a glue application assembly in the glue applicator of the present application.

In the figure, 1, heating the film layer; 2. an adhesive layer silica gel layer; 3. a silica gel layer; 4. an insulating film layer; 5. a glue spreader; 6. a preheating mechanism; 61. an outer housing; 611. a first inlet; 612. a first outlet; 62. a first carry-in roller; 63. a first take-off roller; 64. a driving roller; 65. an exhaust fan; 66. a first compressed air storage tank; 67. a first air heater; 7. a glue spreader mechanism; 71. a glue spreader main body; 711. a second inlet; 712. a second outlet; 72. a second carry-in roller; 73. a second take-off roller; 74. a transfer roller; 741. a first transfer roller; 742. a second transfer roller; 743. a third transfer roller; 75. a scraper; 8. a surface impurity removal mechanism; 81. a surface impurity removal main body; 811. a second compressed air storage tank; 812. a second air heater; 813. an air exhaust pipe; 814. an exhaust fan; 82. driving the roller; 83. an air gun; 831. an air tube; 832. an electromagnetic valve; 9. a gluing component; 91. a silica gel storage tank; 92. a pump; 93. an output main pipe; 94. connecting pipes; 95. an output branch pipe; 951. and flows out of the hole.

Detailed Description

The present application will be described in further detail with reference to fig. 1 and the examples.

Raw materials

1. Vulcanized rubber: a high-quality vulcanized rubber selected from the Ministry of Lida chemical engineering of Dongguan was processed to a thickness of 3 mm.

2. Electronic liquid silica gel: the flame-retardant 94V0 electronic potting silica gel is selected from Shenzhen Hongye Jie science and technology Limited.

3. Heat-conducting silica gel: shenzhen Unitengda technology Limited heat conduction silica gel.

4. And (3) PI film: selected from high temperature resistant polyimide films of ya-an insulation materials ltd, south of Henan province.

5. PET film: is selected from Donglilu Miller X20 PET film of Shenzhen Zhonghe New energy science and technology Limited.

Preparation example

Preparation of heating film: the formula of the heating film is as follows: 20% of HDPE, 25% of metallocene linear low-density polyethylene, 30% of polypropylene, 3% of nano nickel powder, 0.2% of AES fatty alcohol-polyoxyethylene ether sodium sulfate industrial AES surfactant, 6.3% of multi-wall tubular carbon nanotube, 0.5% of graphene, 10% of nano conductive carbon black powder and 5% of PTC reinforcing agent. The preparation process of the heating film comprises the following steps: step 1: weighing HDPE, metallocene linear low density polyethylene and polypropylene according to the proportion, putting the prepared HDPE, metallocene linear low density polyethylene and polypropylene into a dispersion machine, and mixing for 5 minutes at 25 ℃ and 500 r/min; step 2: weighing PTC reinforcing agent, surfactant, nano nickel powder, multi-wall tubular carbon nanotube, graphene and nano conductive carbon black powder according to the proportion, sequentially adding into a dispersion machine, and mixing for 30 minutes at 25 ℃ and 300 r/min; and step 3: putting the materials mixed in the step 2 into a double-screw extruder, wherein the extrusion temperature is 185 ℃, the head temperature is 223 ℃, and the extruded materials are cooled by cooling water and are sent into a granulator to obtain master batches; and 4, step 4: and (4) putting the master batch prepared in the step (3) into a film casting machine, and casting to obtain a heating film with the thickness of 0.1 mm.

Device

Referring to fig. 3, the glue spreader 5 includes a preheating mechanism 6, a glue spreader mechanism 7, and a surface impurity removing mechanism 8 communicated between the preheating mechanism 6 and the glue spreader mechanism 7.

Referring to fig. 4, the preheating mechanism 6 includes an outer casing 61, and a first inlet 611 for the heating film to enter is formed in one side surface of the outer casing 61; the opposite side of the surface of the outer shell 61 with the first inlet 611 is provided with a first outlet 612 for the heated film to flow, and the first inlet 611 and the first outlet 612 have the same height relative to the ground. A first carrying-in roller 62 is rotatably connected inside the outer shell 61, the first carrying-in roller 62 is close to one side of the first inlet 611, and the highest position of the first carrying-in roller 62 relative to the ground is in the same horizontal plane with the first inlet 611. The first carrying-out roller 63 is rotatably connected inside the outer shell 61, the first carrying-out roller 63 is close to one side of the first outlet 612, and the highest position of the first carrying-out roller 63 relative to the ground is in the same horizontal plane with the first outlet 612. Three driving rollers 64 are rotatably connected inside the outer shell 61, one of the three driving rollers 64 is positioned on the upper portion of the first carrying-in roller 62 and on the upper portion of the first carrying-out roller 63, and the vertical projection of the driving roller 64 is positioned in the middle of the vertical projections of the first carrying-in roller 62 and the first carrying-out roller 63. The other two driving rollers 64 are positioned at the lower part of the first carrying-in roller 62 and at the lower part of the first carrying-out roller 63, the vertical projection of the two driving rollers 64 is positioned between the vertical projections of the first carrying-in roller 62 and the first carrying-out roller 63, and the vertical projection of the driving roller 64 positioned at the upper part of the first carrying-in roller 62 is positioned between the two driving rollers 64 positioned at the lower part of the first carrying-in roller 62. The heating film is coiled among the three driving rollers 64, so that the preheating effect on the heating film can be ensured.

Referring to fig. 4, an exhaust fan 65 is fixedly communicated with the top of the outer shell 61; a first compressed air storage tank 66 is communicated with the side wall of the bottom of the outer shell 61; a first air heater 67 is fixedly communicated with the outlet end of the first compressed air storage tank 66; one end of the first air heater 67 is communicated with the first compressed air storage tank 66, and the other end is communicated with the bottom of the outer shell 61.

Referring to fig. 5, the glue spreader mechanism 7 includes a glue spreader main body 71, and a second inlet 711 is formed in one side surface of the glue spreader main body 71; the side opposite to the side of the glue machine main body 71 provided with the second inlet 711 is provided with a second outlet 712, and the heights of the second inlet 711 and the second outlet 712 are equal relative to the ground. The glue spreader main body 71 is rotatably connected with a second carrying-in roller 72, the second carrying-in roller 72 is close to one side of the second inlet 711, and the highest position of the second carrying-in roller 72 relative to the ground is in the same horizontal plane with the second inlet 711. The glue spreader main body 71 is rotatably connected with a second take-out roller 73, the second take-out roller 73 is close to one side of the second outlet 712, and the highest position of the second take-out roller 73 relative to the ground is in the same horizontal plane with the second outlet 712. Three transfer rollers 74 are rotatably attached to the coater body 71, and the vertical projections of the three transfer rollers 74 are positioned between the vertical projections of the second carry-in roller 72 and the second carry-out roller 73. For convenience of distinction, the three conveyance rollers 74 are respectively labeled as a first conveyance roller 741, a second conveyance roller 742, and a third conveyance roller 743 in the conveyance direction of the heating film. The glue spreader main body 71 is provided with a glue spreading assembly 9, and the vertical projection of the glue spreading assembly 9 is positioned between the vertical projections of the second conveying roller 742 and the third conveying roller 743; the glue applicator body 71 is provided with a doctor blade 75, the doctor blade 75 being spaced from the heating film by 0.4mm and the doctor blade 75 being located downstream of the gluing assembly 9.

Referring to fig. 5 and 6, the gluing assembly 9 includes a silica gel storage tank 91, a suction pump 92, an output main pipe 93, a connecting pipe 94, and a plurality of output branch pipes 95, wherein the silica gel storage tank 91 is fixedly connected to the top of the glue spreader main body 71 and is communicated with the suction pump 92; the extraction pump 92 is fixedly connected to the top of the glue spreader main body 71 and is communicated with the output main pipe 93; one end of the output main pipe 93 is communicated with the suction pump 92 and the other end is communicated with the connecting pipe 94; the central axis of the connecting pipe 94 is parallel to the central axis of the second conveying roller 742; a plurality of output branch pipes 95 are fixedly connected and communicated with the circumferential direction of the connecting pipe 94; the glue outlet end of the output branch pipe 95 faces the heating film; adjacent output manifolds 95 are equally spaced. One end of the output branch pipe 95 is communicated with the circumferential direction of the connecting pipe 94, and one end of the output branch pipe is communicated with the outflow hole 951, wherein the diameter of the outflow hole 951 is 1.2 mm. The straight distance between the end of the outlet branch pipe 95 facing away from the connecting pipe 94 and the heating film was 5.0 cm. Wherein, the silica gel storage tank 91 is integrally formed with a jacket layer, and the temperature of the silica gel stored in the jacket layer is controlled by introducing cooling water into the jacket layer.

Referring to fig. 5, the surface cleaning mechanism 8 includes a surface cleaning body 81, and the first outlet 612 and the second inlet 711 have the same height with respect to the ground. The surface impurity removing body 81 is rotatably connected with a driving roller 82, and the highest position of the driving roller 82 relative to the ground is equal to the height of the first outlet 612 relative to the ground. The top of the surface impurity removing main body 81 is communicated with a second compressed air storage tank 811, and the second compressed air storage tank 811 is communicated with a second air heater 812. The top of the surface impurity removing main body 81 is communicated with an air exhaust pipe 813, and the air exhaust pipe 813 is communicated with an exhaust fan 814 arranged on the ground. The inner wall of the surface impurity removing main body 81 is fixedly connected with an air gun 83, the air outlet end of the air gun 83 inclines 45 degrees towards the surface of the heating film, the air gun 83 is communicated with the second compressed air storage tank 811 through an air pipe 831, and an electromagnetic valve 832 is installed on the air pipe 831.

Examples

Example 1

Referring to fig. 1, the silica gel heating sheet disclosed in the present application includes a heating film layer 1 as a core layer, and adhesive layers 2 are adhered to both sides of the heating film layer 1; the adhesive layer 2 is adhered with a silica gel layer 3; the heating film layer 1 is an aluminum foil; the adhesive layer 2 is electronic liquid silica gel; the silica gel layer 3 is made of vulcanized rubber.

The processing technology of the silica gel heating plate comprises the following steps:

step 1: coating electronic liquid silica gel with the thickness of 0.4mm on one surface of the aluminum foil by using a glue spreader;

step 2: compounding the cooked rubber on one side of the electronic liquid silica gel with the thickness of 0.4mm of the aluminum foil by adopting a cold mounting machine, wherein the pressing temperature is as follows: 30.1 ℃, the pressure is 1000N, and the humidity is controlled to be 60 percent;

and step 3: coating electronic liquid silica gel with the thickness of 0.4mm on the other surface of the aluminum foil by using a glue spreader;

and 4, step 4: compounding the cooked rubber on one side of the electronic liquid silica gel with the thickness of 0.4mm of the aluminum foil by adopting a cold mounting machine, wherein the pressing temperature is as follows: controlling the pressure at 1000N and the humidity at 60% at 30.2 deg.C to obtain the final product.

Example 2

Example 2 differs from example 1 in that: the heating film layer 1 is the heating film in the preparation example.

Example 3

Example 3 differs from example 1 in that: the silica gel is heat-conducting silica gel.

Example 4

Example 4 differs from example 1 in that: coating silica gel on one surface of the heating film in the step 1 to be 0.8mm in thickness; and (3) coating silica gel on the other surface of the heating film in the step 3 to a thickness of 0.8 mm.

Example 5

Example 5 differs from example 1 in that: referring to fig. 2, the thermal film layer 1 is compounded with insulating film layers 4 on both surfaces; the insulating film layer 4 is positioned between the adhesive layer 2 and the heating film layer 1; the insulating film layer 4 is a PI film.

step 1: adopting the spreading machine to scrape 0.05 mm's electron liquid silica gel to the surperficial blade coating of aluminium foil, adopting cold mount machine with the PI membrane compound in one side of the 0.05 mm's of aluminium foil electron liquid silica gel, the pressfitting temperature: 30.1 ℃, the pressure is 1000N, and the humidity is controlled to be 60 percent; adopting the spreading machine to scrape and coat 0.05 mm's electron liquid silica gel to another surface of aluminium foil, adopting cold mounting machine with the PI membrane compound in one side of the 0.4 mm's of aluminium foil electron liquid silica gel, the pressfitting temperature: 30.0 ℃, the pressure is controlled to be 1000N, and the humidity is controlled to be 60 percent.

Step 2: coating electronic liquid silica gel with the thickness of 0.4mm on one surface of the aluminum foil by using a glue spreader;

and step 3: compounding the cooked rubber on one side of the electronic liquid silica gel with the thickness of 0.4mm of the aluminum foil by adopting a cold mounting machine, wherein the pressing temperature is as follows: 30.1 ℃, the pressure is 1000N, and the humidity is controlled to be 60 percent;

and 4, step 4: coating electronic liquid silica gel with the thickness of 0.4mm on the other surface of the aluminum foil by using a glue spreader;

and 5: compounding the cooked rubber on one side of the electronic liquid silica gel with the thickness of 0.4mm of the aluminum foil by adopting a cold mounting machine, wherein the pressing temperature is as follows: controlling the pressure at 1000N and the humidity at 60% at 30.2 deg.C to obtain the final product.

Example 6

Example 6 differs from example 5 in that: the insulating film layer 4 is a PET film.

Example 7

Example 7 differs from example 1 in that: the processing technology of the silica gel heating plate comprises the following steps:

step 1: sending the heating film into a glue spreader 5 for temperature control treatment, controlling the temperature at 20.1 ℃, blowing the surface of the heating film to be coated with the silica gel by using an air cavity air gun after the temperature control treatment, and removing dust and impurity metals on the surface; meanwhile, the temperature of the silica gel in the silica gel storage tank 91 is controlled to 15.2 ℃.

and 5: compounding the cooked rubber on one side of the electronic liquid silica gel with the thickness of 0.4mm of the aluminum foil by adopting a cold mounting machine, wherein the pressing temperature is as follows: 30.2 ℃, the pressure is controlled to be 1000N, the humidity is controlled to be 60 percent,

step 6: post-treatment, namely, heating a silica gel sheet, and firstly entering a first treatment area at the temperature of 40.3 ℃ for 200 smin; and then entering a second treatment area at the temperature of 20.1 ℃ for 5min to finish post-treatment operation, thus obtaining the target product.

Comparative example

Comparative example 1:a process of a silica gel heating sheet comprises the following steps: the operation was carried out using a vulcanization press, the heating film was an aluminum foil as in the examples, and the high temperature vulcanization was carried out at 200 ℃ under a hot pressing pressure of 2 x 10⁴N; the adhesive layer is made of high-temperature-resistant adhesive and can resist the temperature of 300 ℃; and (3) a pressing mode: and pressing a flat plate of a vulcanizing press to prepare the silica gel heating sheet.

Performance test

1. And (3) testing the voltage breakdown resistance: the silica gel heating sheets of examples 1 to 7 and comparative example 1 were cut into test samples 1 to 7 and comparative example 1, respectively, each having a specification of 20cm × 15mm, and the test samples 1 to 7 and comparative example 1 were tested for 1 minute under a 2000V voltage withstand voltage test to see whether or not there was a breakdown phenomenon.

2. And (3) testing the peel strength: the silicone rubber heating sheets of examples 1-7 and comparative example 1 were cut into test samples 1-7 and comparative test 1, respectively, of specification 20cm x 15mm, the test samples 1-7 and comparative test 1 being tested according to GB/T2791-.

3. Testing power voltage: under the condition that the power supply voltage is AC220V, testing the current passing through the heating plate by using an ammeter, wherein the power P = UI, and the power of the heating plate can be tested; and testing the heating temperature of the surface of the heating sheet by adopting a digital display temperature transmitter.

Detection method/test method

Table 1 shows the test parameters of test samples 1 to 7 and comparative test 1

It can be seen from the combination of examples 1 to 7 and comparative example 1 and table 1 that the voltage breakdown resistance of test samples 1 to 7 is similar to that of comparative test 1, and the test duration is 1 minute under the voltage breakdown resistance test of 2000V, so that the test has no breakdown phenomenon and better safety performance.

As can be seen by combining examples 1-7 with comparative example 1 and table 1, the peel strengths of test samples 1-7 are compared with the peel strength of comparative test 1, and the peel strengths of test samples 1-7 are similar to the peel strength of comparative test 1, wherein the absolute value of the difference between the peel strengths of test samples 1-6 and comparative test 1 is 2.0N/3 cm, and the peel strength of test sample 7 is 0.23N/3 cm higher than the peel strength of comparative test 1, therefore, the peel strength of the product prepared by the process of the present application is similar to the peel strength of the product prepared by the prior art, and the production requirements of the silica gel heating sheet can be satisfied.

Claims

1. A silica gel cold-bonding process is characterized in that: the method comprises the following steps:

step 1: coating silica gel on one surface of the heating film by using a glue spreader, wherein the silica gel is electronic liquid silica gel or heat-conducting silica gel, and the formula of the heating film layer is as follows: 20% of HDPE, 25% of metallocene linear low-density polyethylene, 30% of polypropylene, 3% of nano nickel powder, 0.2% of surfactant, 6.3% of multi-wall tubular carbon nanotube, 0.5% of graphene, 10% of nano conductive carbon black powder and 5% of PTC reinforcing agent;

step 2: compounding the cooked rubber on the side, coated with the silica gel, of the heating film by adopting a cold laminating machine, wherein the laminating temperature is as follows: 30 ℃. + -. 2 ℃, pressure: 1000N, and controlling the humidity to be 60% +/-5%;

and step 3: coating silica gel on the other surface of the heating film in a scraping manner, wherein the silica gel is electronic liquid silica gel or heat-conducting silica gel;

and 4, step 4: compounding the cooked rubber on the side, coated with the silica gel, of the heating film by adopting a cold laminating machine, wherein the laminating temperature is as follows: 30 ℃. + -. 2 ℃, pressure: 1000N, and controlling the humidity to be 60% +/-5%, thus obtaining the target product.

2. The cold-bonding process of silica gel according to claim 1, characterized in that: one surface of the heating film in the step 1 is coated with silica gel in a scraping way, and the thickness of the silica gel is 0.2-2.0 mm; and (3) coating silica gel on the other surface of the heating film in the step 3 to form a coating with the thickness of 0.2-2.0 mm.

3. The cold-bonding process of silica gel according to claim 1, characterized in that: before the step 1, firstly, carrying out temperature control treatment on the heating film, wherein the temperature is controlled to be 20 +/-2 ℃; the temperature of the silica gel between the doctor blade was controlled at 15. + -. 2 ℃.

4. The cold-bonding process of silica gel according to claim 2, characterized in that: before the step 1, the heating film is subjected to temperature control treatment at 20 +/-2 ℃, and then the surface of the heating film to be coated with the silica gel is blown by an air gun.

5. The cold-bonding process of silica gel according to claim 1, characterized in that: the step 4: compounding the cooked rubber on the side, coated with the silica gel, of the heating film by adopting a cold laminating machine, wherein the laminating temperature is as follows: 30 ℃. + -. 2 ℃, pressure: 1000N, after the pressing is finished, performing post-treatment to obtain a target product; the post-treatment comprises the following steps: the silica gel heating sheet after the pressing is finished firstly enters a first processing area with the temperature of 40 +/-1 ℃ for 2-3 min; then enters a second treatment area with the temperature of 20 +/-2 ℃ for 4-5 min.

6. A silica gel heating sheet prepared by the silica gel cold-bonding process according to any one of claims 1 to 5, which is characterized in that: comprises a heating film layer (1) as a core layer, wherein adhesive layers (2) are adhered to both surfaces of the heating film layer (1); the adhesive layer (2) is adhered with a silica gel layer (3); the adhesive layer (2) is electronic liquid silica gel or heat-conducting silica gel; the silica gel layer (3) is made of vulcanized rubber.

7. The silica gel heating sheet prepared by the silica gel cold bonding process according to claim 6, wherein: the two surfaces of the heating film layer (1) are compounded with insulating film layers (4); the insulating film layer (4) is positioned between the adhesive layer (2) and the heating film layer (1); the insulating film layer (4) is a PI layer or a PET layer.