In the application of temperature-resistant non-stick coatings for household appliances such as rice cookers, ovens, grills, and range hoods, the coating must withstand long-term high-temperature use while maintaining high gloss and high fineness for decorative purposes. It also needs to have a pencil hardness of ≥3H and excellent resistance to yellowing. Polyester-modified silicone resin 6038A, based on the polyester modification of 6072A, improves the high-temperature yellowing resistance while maintaining high gloss and hardness by adjusting the molecular structure. This resin has a solid content of 59±1%, a viscosity of 350-1000 mPa.s, and a hardness of ≥3H after curing, making it a candidate base material for temperature-resistant non-stick and decorative coatings for household appliances.


Why do the temperature-resistant non-stick coatings of household appliances often show insufficient hardness, yellowing, or adhesion loss during high-temperature curing or long-term use?


Improper curing conditions - 250℃×20min, 270℃×15min, and 280℃×10min can all achieve complete curing, but insufficient curing temperature will result in insufficient crosslinking density.


The diluent contains water, sulfur compounds, or pyridine and other impurities, which affect the adhesion, drying, and high-temperature performance of the paint film.


During coating application, dust, foreign substances, or water are mixed in, causing coating defects and affecting hardness and appearance.


Acids, bases, amines, etc. are mixed in, accelerating curing or affecting heat resistance and electrical properties.


Insufficient treatment of the substrate (oil removal, sandblasting roughness) affects the adhesion of the coating during high-temperature use.


The control of yellowing after high-temperature baking needs to be verified based on the specific formula and curing process.


The relationship between curing conditions and performance


Curing method Conditions Applicable scenarios Performance characteristics
Standard curing 250℃×20min Conventional baking process Hardness ≥3H, high gloss, good fineness
Fast curing 270℃×15min Increase production efficiency Hardness ≥3H, high gloss
Fast curing 280℃×10min High-efficiency production line Hardness ≥3H, high gloss
What conditions need to be confirmed before selection and application?


Condition category Information to be confirmed
Curing equipment Whether it has the ability to bake at 250-280℃ and temperature uniformity
Application method Spraying, brushing, immersion coating, etc.
Substrate type Metal (aluminum, stainless steel, cold-rolled steel, etc.) and pre-treatment method
Diluent Ensure no water, sulfur compounds, pyridine and other impurities
Equipment cleanliness Clean and dust-free, no water, no foreign substances
Storage isolation Away from acids, bases, amines, etc.
Performance goals Hardness (≥3H), gloss, fineness, resistance to yellowing, non-stick performance
Which key indicators need to be verified?


Verification items Primary function Not replaceable content
Curing hardness (≥3H) Verify curing degree and scratch resistance Hardness达标 does not mean non-stick performance is qualified
Coating appearance (gloss， fineness) Evaluate decorative effect Need to re-evaluate after high-temperature use
High-temperature resistance to yellowing Verify color stability after high-temperature use Need to simulate actual use temperature and time
Adhesion Assess interface bonding quality Re-test after high-temperature use
Non-stick performance Verify functional requirements Need to simulate actual cooking conditions for testing
Common misunderstandings


Low temperature and long time can replace the recommended curing conditions
The recommended curing conditions (250℃×20min， 270℃×15min， 280℃×10min) are designed based on the crosslinking kinetics of the resin system. Lowering the recommended temperature or time may affect the final hardness and heat resistance.


Any diluent can be used
The diluent must not contain water， sulfur compounds， pyridine and other impurities. Otherwise， it will affect the adhesion， drying， and other properties of the paint film.


The higher the curing temperature， the higher the hardness
In the recommended temperature range (250-280℃)， choosing an appropriate time combination can achieve the target hardness. Exceeding the recommended range may cause thermal damage to the resin.


The uncleanliness of the equipment will not affect the coating performance.
The introduction of dust, foreign substances or moisture will cause coating defects, affecting the uniformity of hardness, gloss and adhesion.


Recommended steps


Confirm whether the baking equipment meets the curing requirements of 250-280℃.


Select appropriate curing conditions (250℃×20min, 270℃×15min or 280℃×10min).


Confirm the purity of the thinner and the cleanliness of the equipment.


Verify the appearance (gloss, fullness) and hardness (≥3H) of the coating on a small sample.


Conduct adhesion tests and high-temperature yellowing resistance verification.


Based on the actual household appliance usage conditions, conduct non-stick performance and durability tests.


Optimize the construction parameters and coating design according to the verification results.


FAQ


What are the main differences between IOTA 6038A and 6072A?
Both are polyester-modified silicone resins. 6038A has further optimized the high-temperature yellowing resistance performance based on 6072A. After curing, the hardness is ≥ 3H, and it is recommended for household non-stick coatings with high requirements for yellowing resistance.


What are the recommended curing conditions?
250℃×20 minutes, 270℃×15 minutes, or 280℃×10 minutes can all achieve complete curing.


What does ≥ 3H mean?
A pencil hardness of ≥ 3H indicates that the coating has good scratch resistance and can meet the requirements for wear resistance in household appliance non-stick coatings.


Why is the quality of the thinner particularly important?
Impurities such as water, sulfur compounds, or pyridine in the thinner can seriously affect the adhesion of the paint film, drying time, and other properties.


What effects do acids, bases, amines, etc. have on the resin?
These substances accelerate the curing process of this product and affect the heat resistance and electrical properties. They should be strictly isolated during storage.