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CN-121974567-A - Glass powder, dielectric paste and thick film heating element

CN121974567ACN 121974567 ACN121974567 ACN 121974567ACN-121974567-A

Abstract

The invention provides a glass powder, a dielectric paste and a thick film heating element. The glass powder comprises, by weight, 7-20% of B 2 O 3 15-40%、MgO 15-40%、CaO 20-50%、SiO 2 and 0.1-8% of glass powder auxiliary agent based on 100% of the total weight of the glass powder raw material. The medium slurry comprises 55-80% of the glass powder, 0-5% of cobalt blue, 8-35% of an organic carrier, 3-15% of a diluent, 0.5-3% of an inorganic additive and 0.2-1% of an auxiliary agent by taking the total weight of the medium slurry as 100%. The invention also provides a thick film heating element made of the dielectric paste. The dielectric layer formed by the dielectric slurry is compact, does not crack, has strong binding force with stainless steel, good breakdown voltage resistance and excellent electrical property.

Inventors

  • CHEN CHUNJIN
  • ZHENG WENBIN
  • WANG SHAN
  • ZHOU XINSHAN

Assignees

  • 苏州晶银新材料科技有限公司

Dates

Publication Date
20260505
Application Date
20251225

Claims (12)

  1. 1. The glass powder comprises, by taking the total weight of raw materials of the glass powder as 100%, 7-20% of B 2 O 3 15-40%、MgO 15-40%、CaO 20-50%、SiO 2 and 0.1-8% of glass powder auxiliary agent.
  2. 2. The glass frit according to claim 1, wherein the glass frit additive comprises one or a combination of two or more of Fe 2 O 3 、Al 2 O 3 、ZrO 2 、La 2 O 3 and SrO.
  3. 3. The glass frit according to claim 1, wherein the weight ratio of B 2 O 3 、SiO 2 , mgO, caO is (15-25): (7-10): (35-40): (35-50).
  4. 4. The glass frit according to claim 1, wherein the glass frit has a particle diameter D50 of 1.0 to 6.5 μm and a particle diameter D100 of 40.0 μm or less; Preferably, the particle diameter D50 of the glass powder is 1.5-5.0 mu m; more preferably, the glass frit has a particle size D50 of 2.0 to 4.0 μm.
  5. 5. The glass frit according to claim 1, wherein the glass transition temperature of the glass frit is 580-680 ℃ and/or the average coefficient of thermal expansion of the glass frit at 50-400 ℃ is 10ppm/°c-12ppm/°c; preferably, the glass frit has an average coefficient of thermal expansion of from 50 to 400 ℃ of from 10.5ppm/°c to 12ppm/°c; more preferably, the glass frit has an average coefficient of thermal expansion of from 50 to 400 ℃ of from 11ppm/°c to 12ppm/°c.
  6. 6. A medium slurry, based on 100% of the total weight of the medium slurry, comprises 55-80% of glass powder according to any one of claims 1-5, 0-5% of cobalt blue, 8-35% of organic carrier, 3-15% of diluent, 0.5-3% of inorganic additive and 0.2-1% of auxiliary agent.
  7. 7. The media slurry of claim 6, wherein the organic carrier comprises a resin and a solvent; Preferably, the resin includes one or a combination of two or more of ethyl cellulose resin, cellulose acetate butyrate resin, and acrylic resin; preferably, the solvent comprises one or a combination of more than two of butyl carbitol acetate, terpineol, DBE and butyl carbitol.
  8. 8. The media slurry of claim 7, wherein the weight ratio of the resin to the solvent is (13-35): 65-81; Preferably, the weight ratio of the ethyl cellulose resin, the cellulose acetate butyrate resin, the acrylic resin and the solvent is (8-20): 3-8): 2-7): 65-81.
  9. 9. The media slurry of claim 6, wherein the diluent comprises one or a combination of two or more of terpineol, butyl carbitol, benzyl alcohol, dimethyl adipate.
  10. 10. The media slurry of claim 6, wherein the inorganic additive comprises one or a combination of two or more of titanium dioxide, copper oxide, nickel oxide, zirconium oxide, lanthanum oxide.
  11. 11. The media slurry of claim 6, wherein the auxiliary agent comprises a thixotropic agent and a dispersing agent; Preferably, the thixotropic agent comprises one or more of Thixatrol MAX, CRAYVALLAC MT and organic bentonite, and the dispersing agent comprises one or more of SC-1015F and 211P, AFB-1521.
  12. 12. A thick film heating element, the raw materials of which comprise the dielectric paste as defined in any one of claims 6 to 11; preferably, the substrate of the thick film heater is made of SUS630 stainless steel, a dielectric layer is arranged on the surface of the substrate, and the dielectric layer is formed by sintering the dielectric slurry.

Description

Glass powder, dielectric paste and thick film heating element Technical Field The invention relates to the technical field of heating element manufacturing, in particular to a glass powder, dielectric paste and thick film heating element. Background The concept of thick film is mainly relative to thin film, and thick film refers to a film layer formed on a substrate by printing sintering technology and having a thickness of several micrometers to tens of micrometers, and a material for manufacturing the film layer is called a thick film material. The thick film heating element has the advantages of high power density, high heating speed, high working temperature, high heating rate, high mechanical strength, small volume, convenient installation, uniform heating temperature field, long service life, energy conservation, environmental protection, safety and the like. At present, the novel, safe, environment-friendly and excellent-performance heating element advocates energy conservation and environment protection is widely valued and applied in various industries, and the traditional heating mode is gradually replaced. The thick film heater is mainly formed by printing insulating medium, heating resistor, conductor material, protective medium and other materials on a heater substrate in sequence by means of thick film screen printing technology and sintering at high temperature. Stainless steel has the advantages of excellent mechanical and thermal shock resistance, moderate cost, easy processing and the like, and becomes an ideal choice of a substrate for a high-power thick film circuit. The microcrystalline glass powder mentioned in CN101419850A consists of SiO2、B2O3、Al2O3、BaO、CaO、MgO、ZrO2、Co2O3、TiO2 and is a microcrystalline glass with a high barium system mainly containing BaO, the thermal expansion coefficient is improved by adding Ba, and the mechanical strength and the thermal shock resistance and the breakdown strength are improved by crystallization mainly containing Ba. However, in this solution, various Ba crystal forms of the glass ceramics are precipitated, including h-BaAl 2Si2O8 (thermal expansion coefficient 8 ppm/°c) and Celsian-Ba Al 2Si2O8 (thermal expansion coefficient 2.3 ppm/°c), the precipitated crystal phase is poorly controlled, the crystal forms are transformed at different temperatures, the thermal expansion coefficients are greatly changed, the thermal expansion coefficients of the glass and the stainless steel are mismatched, and the coating is cracked due to the mismatch of the thermal expansion coefficients, and the thermal expansion coefficients of the glass and the corresponding coating quality are not examined in this patent. The existing dielectric paste for thick films does not consider the problem of matching the thermal expansion coefficient with stainless steel, and mainly matches with SUS304, SUS316, SUS430 stainless steel, and there is no study on the dielectric paste matching the thermal expansion coefficient of SUS630 stainless steel. Disclosure of Invention In order to solve the problems, the invention aims to provide a glass powder, a dielectric paste and a thick film heating element. The dielectric layer formed by the dielectric slurry is compact, does not crack, has strong binding force with stainless steel, good breakdown voltage resistance and excellent electrical property. In order to achieve the aim, the invention provides glass powder, which comprises, by taking the total weight of raw materials of the glass powder as 100%, 7-20% of B 2O3 15-40%、MgO 15-40%、CaO 20-50%、SiO2 and 0.1-8% of glass powder auxiliary agent. In the glass frit, the sum of the weight of the respective raw materials may be 100%. In the above glass frit, the glass frit auxiliary agent generally includes an inorganic oxide. Specifically, the glass powder auxiliary agent comprises one or more than two of Fe 2O3、Al2O3、ZrO2、La2O3 and SrO. In the glass powder, the raw materials of the glass powder comprise 0.1-8% of glass powder auxiliary agent and further comprise 1-4% of glass powder auxiliary agent, wherein the total weight of the glass powder raw materials is 100%. That is, the raw materials of the glass powder comprise, by taking the total weight of the glass powder as 100%, B 2O3 15-40%、MgO 15-40%、CaO 20-50%、SiO2 -20%, 0.1-8% (further 1-4%) of glass powder auxiliary agents, and the sum of the weight of the raw materials can be 100%. According to a specific embodiment of the present invention, the weight ratio of B 2O3 in the raw material of the glass frit may be 15 to 40%, for example, 15%, 20%, 25%, 30%, 35%, 40%, etc. specific values and ranges having any two of the above specific values as endpoints. According to a specific embodiment of the present invention, the weight ratio of MgO in the raw material of the glass frit may be 15 to 40%, for example, 15%, 20%, 25%, 30%, 35%, 40%, etc. specific values and ranges ending with any two of the above specific values. According to a specific