A method for preparing a special coating for inner cover of an electric rice cooker

Abstract

The invention discloses a method for preparing a special coating for an inner cover of an electric rice cooker, and relates to the technical field of processing accessories of electric rice cookers. The surface of the inner cover of the electric rice cooker is pretreated, and then sprayed with a specific coating, and then cured to form a coating; the pretreatment comprises: cleaning and deposition; the invention forms a protective layer on the surface of the inner cover of the electric rice cooker by first depositing the surface of the inner cover of the electric rice cooker, and then spraying the special coating, so as to play a strong protective role on the inner cover of the electric rice cooker. At the same time, since the adhesion of the special coating is relatively general when it is directly sprayed on the surface of the inner cover of the electric rice cooker made of stainless steel, the coating is prone to cracking and falling off after long-term use. Therefore, the invention greatly improves the microstructure of the surface of the inner cover of the electric rice cooker made of stainless steel by first depositing the surface of the inner cover of the electric rice cooker, so that the microstructure can be combined with the coating formed by the special coating, thereby extending the service life of the formed coating.

Description

Technical Field

[0001] The invention belongs to the technical field of processing electric rice cooker accessories, in particular to a method for preparing a special coating for an inner cover of an electric rice cooker. Background Art

[0002] The rice cooker is a modern cooking utensil that can perform multiple processing functions such as steaming, boiling, stewing, simmering and braising.

[0003] An electric rice cooker is a kitchen appliance that uses electric heat to cook food. The operating temperature inside an electric rice cooker is mostly around 100°C.

[0004] In modern kitchens, electric rice cookers have become an indispensable cooking tool, and the inner cover of the electric rice cooker is an important component used therein. However, in the prior art, the electric rice cooker uses an inner cover made of metal, which is easily corroded due to the need to contact water for a long time, resulting in a significant shortening of its service life.

[0005] Based on this, a method for preparing a special coating for an inner cover of an electric rice cooker is provided to solve the existing technical problems. Summary of the invention

[0006] The purpose of the invention is to provide a method for preparing a special coating for an inner cover of an electric rice cooker, so as to solve the deficiencies in the prior art.

[0007] The technical solution adopted by the present invention is as follows:

[0008] A method for preparing a special coating for an inner cover of an electric rice cooker, wherein the surface of the inner cover of the electric rice cooker is pretreated, and then a specific coating is sprayed and cured to form the coating;

[0009] The pretreatment includes: cleaning and deposition;

[0010] The specific coating comprises the following ingredients by weight: 30-35 parts of water-based fluorocarbon resin, 2-3 parts of film-forming aid, 1-2 parts of hollow microspheres, 0.1-0.3 parts of defoaming agent, 0.5-0.8 parts of leveling agent, 3-5 parts of calcined intercalated bentonite, 0.3-0.6 parts of propylene glycol methyl ether acetate, and 18-25 parts of water.

[0011] As a further technical solution: the inner cover of the rice cooker is made of 304 stainless steel;

[0012] The cleaning comprises: placing the inner cover of the rice cooker in acetone for cleaning for 10-15 minutes, and then drying it to a constant weight;

[0013] The deposition process is:

[0014] Connect the inner cover of the rice cooker to the negative pole of the power supply, connect the graphite to the positive pole of the power supply, then immerse the inner cover of the rice cooker and the graphite in the deposition liquid at the same time, start the power supply, and perform the deposition treatment for 10-16 minutes, then take it out, wash it with deionized water for 10 minutes, and then vacuum dry it to constant weight;

[0015] The deposition process was performed at a temperature of 58°C and a voltage of 6-8V.

[0016] As a further technical solution: the deposition liquid is:

[0017] A mixture of hydroxypropionic acid, boric acid, zirconium nitrate, aluminum nitrate, and phosphate;

[0018] The mass fraction of zirconium nitrate is 2%;

[0019] The mass fraction of aluminum nitrate is 1%;

[0020] The mass fraction of hydroxypropionic acid is 0.2%;

[0021] The mass fraction of boric acid is 1%;

[0022] The mass fraction of phosphate is 2.5%.

[0023] As a further technical solution: the phosphate is sodium phosphate or potassium phosphate.

[0024] As a further technical solution: the vacuum drying temperature is 60° C. and the time is 10 hours.

[0025] As a further technical solution: the film-forming aid is propylene glycol methyl ether acetate.

[0026] As a further technical solution: the defoamer is a silicone defoamer.

[0027] As a further technical solution: the leveling agent is an acrylic leveling agent.

[0028] As a further technical solution: the preparation method of the calcined intercalated bentonite is:

[0029] Firstly, cetyltrimethylammonium bromide is added into deionized water to prepare a cetyltrimethylammonium bromide solution with a mass fraction of 5%;

[0030] Bentonite was added to the hexadecyltrimethylammonium bromide solution, and the temperature was adjusted to 85°C under a vacuum of 0.1 Pa, and the mixture was stirred for 4 hours. Then, the mixture was discharged, filtered, washed, and dried at 100°C for 30 minutes to obtain intercalated bentonite.

[0031] calcining the intercalated bentonite obtained above to obtain calcined intercalated bentonite;

[0032] The calcination treatment temperature is 550° C. and the time is 35 minutes. Beneficial Effects

[0033] The present invention forms a protective layer on the surface of the inner cover of the rice cooker by first performing a deposition treatment on the surface of the inner cover of the rice cooker and then spraying a special coating, thereby effectively protecting the inner cover of the rice cooker. At the same time, since the adhesion of the special coating is relatively general when it is directly sprayed on the surface of the inner cover of the rice cooker made of stainless steel, the coating is prone to cracking and falling off after long-term use. Therefore, the present invention greatly improves the microstructure of the surface of the inner cover of the rice cooker made of stainless steel by first performing a deposition treatment on the surface of the inner cover of the rice cooker, thereby enhancing the bonding strength of the coating formed by the special coating, thereby extending the service life of the formed coating.

[0034] By forming a specific coating on the surface of the inner cover of the electric rice cooker, the inner cover of the electric rice cooker can be used for a long time in a high temperature environment without being easily deformed or corroded.

[0035] The present invention introduces calcined intercalated bentonite into the special coating, which can significantly improve the surface water contact angle of the coating, so that the formed coating surface has a higher hydrophobic property. At the same time, it can also form a more stable coating structure by uniformly dispersing it in the coating and tightly combining it with polymer molecules, and the aging resistance of the coating is greatly improved. DETAILED DESCRIPTION

[0036] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention. Example 1

[0037] A method for preparing a special coating for an inner cover of an electric rice cooker, wherein the surface of the inner cover of the electric rice cooker is pretreated, and then a specific coating is sprayed and cured to form the coating;

[0038] The pretreatment includes: cleaning and deposition;

[0039] The specific coating comprises the following ingredients by weight: 30 parts of water-based fluorocarbon resin, 2 parts of propylene glycol methyl ether acetate, 1 part of hollow microspheres, 0.1 parts of silicone defoamer, 0.5 parts of acrylic leveling agent, 3 parts of calcined intercalated bentonite, 0.3 parts of propylene glycol methyl ether acetate, and 18 parts of water.

[0040] The inner cover of the rice cooker is 304 stainless steel;

[0041] The cleaning comprises: placing the inner cover of the rice cooker in acetone for cleaning for 10 minutes, and then drying it to a constant weight;

[0042] The deposition process is:

[0043] Connect the inner cover of the rice cooker to the negative pole of the power supply, connect the graphite to the positive pole of the power supply, then immerse the inner cover of the rice cooker and the graphite in the deposition liquid at the same time, start the power supply, and perform the deposition treatment for 10 minutes, then take it out, wash it with deionized water for 10 minutes, and then vacuum dry it to constant weight;

[0044] The deposition process was performed at a temperature of 58°C and a voltage of 6V.

[0045] The deposition liquid is:

[0046] A mixture of hydroxypropionic acid, boric acid, zirconium nitrate, aluminum nitrate, and phosphate;

[0047] The mass fraction of zirconium nitrate is 2%;

[0048] The mass fraction of aluminum nitrate is 1%;

[0049] The mass fraction of hydroxypropionic acid is 0.2%;

[0050] The mass fraction of boric acid is 1%;

[0051] The mass fraction of phosphate is 2.5%.

[0052] The phosphate is sodium phosphate or potassium phosphate.

[0053] The vacuum drying temperature was 60°C and the time was 10 hours.

[0054] The preparation method of calcined intercalated bentonite is as follows:

[0055] Firstly, cetyltrimethylammonium bromide is added into deionized water to prepare a cetyltrimethylammonium bromide solution with a mass fraction of 5%;

[0056] Bentonite was added to the hexadecyltrimethylammonium bromide solution, and the temperature was adjusted to 85°C under a vacuum of 0.1 Pa, and the mixture was stirred for 4 hours. Then, the mixture was discharged, filtered, washed, and dried at 100°C for 30 minutes to obtain intercalated bentonite.

[0057] calcining the intercalated bentonite obtained above to obtain calcined intercalated bentonite;

[0058] The calcination treatment temperature is 550° C. and the time is 35 minutes.

[0059] Example 2

[0060] A method for preparing a special coating for an inner cover of an electric rice cooker, wherein the surface of the inner cover of the electric rice cooker is pretreated, and then a specific coating is sprayed and cured to form the coating;

[0061] The pretreatment includes: cleaning and deposition;

[0062] The specific coating comprises the following ingredients by weight: 32 parts of water-based fluorocarbon resin, 2.5 parts of propylene glycol methyl ether acetate, 1.2 parts of hollow microspheres, 0.2 parts of silicone defoamer, 0.6 parts of acrylic leveling agent, 3.5 parts of calcined intercalated bentonite, 0.4 parts of propylene glycol methyl ether acetate, and 20 parts of water.

[0063] The inner cover of the rice cooker is 304 stainless steel;

[0064] The cleaning comprises: placing the inner cover of the rice cooker in acetone for cleaning for 12 minutes, and then drying it to a constant weight;

[0065] The deposition process is:

[0066] Connect the inner cover of the rice cooker to the negative pole of the power supply, connect the graphite to the positive pole of the power supply, then immerse the inner cover of the rice cooker and the graphite in the deposition liquid at the same time, start the power supply, and perform the deposition treatment for 12 minutes, then take it out, wash it with deionized water for 10 minutes, and then vacuum dry it to constant weight;

[0067] The deposition process was performed at a temperature of 58°C and a voltage of 7V.

[0068] The deposition liquid is:

[0069] A mixture of hydroxypropionic acid, boric acid, zirconium nitrate, aluminum nitrate, and phosphate;

[0070] The mass fraction of zirconium nitrate is 2%;

[0071] The mass fraction of aluminum nitrate is 1%;

[0072] The mass fraction of hydroxypropionic acid is 0.2%;

[0073] The mass fraction of boric acid is 1%;

[0074] The mass fraction of phosphate is 2.5%.

[0075] The phosphate is sodium phosphate or potassium phosphate.

[0076] The vacuum drying temperature was 60°C and the time was 10 hours.

[0077] The preparation method of calcined intercalated bentonite is as follows:

[0078] Firstly, cetyltrimethylammonium bromide is added into deionized water to prepare a cetyltrimethylammonium bromide solution with a mass fraction of 5%;

[0079] Bentonite was added to the hexadecyltrimethylammonium bromide solution, and the temperature was adjusted to 85°C under a vacuum of 0.1 Pa, and the mixture was stirred for 4 hours. Then, the mixture was discharged, filtered, washed, and dried at 100°C for 30 minutes to obtain intercalated bentonite.

[0080] calcining the intercalated bentonite obtained above to obtain calcined intercalated bentonite;

[0081] The calcination treatment temperature is 550° C. and the time is 35 minutes.

[0082] Example 3

[0083] A method for preparing a special coating for an inner cover of an electric rice cooker, wherein the surface of the inner cover of the electric rice cooker is pretreated, and then a specific coating is sprayed and cured to form the coating;

[0084] The pretreatment includes: cleaning and deposition;

[0085] The specific coating comprises the following ingredients by weight: 33 parts of water-based fluorocarbon resin, 2.5 parts of propylene glycol methyl ether acetate, 2 parts of hollow microspheres, 0.2 parts of silicone defoamer, 0.7 parts of acrylic leveling agent, 4 parts of calcined intercalated bentonite, 0.4 parts of propylene glycol methyl ether acetate, and 21 parts of water.

[0086] The inner cover of the rice cooker is 304 stainless steel;

[0087] The cleaning comprises: placing the inner cover of the rice cooker in acetone for cleaning for 12 minutes, and then drying it to a constant weight;

[0088] The deposition process is:

[0089] Connect the inner cover of the rice cooker to the negative pole of the power supply, connect the graphite to the positive pole of the power supply, then immerse the inner cover of the rice cooker and the graphite in the deposition liquid at the same time, start the power supply, and perform the deposition treatment for 15 minutes, then take it out, wash it with deionized water for 10 minutes, and then vacuum dry it to constant weight;

[0090] The deposition process was performed at a temperature of 58°C and a voltage of 7V.

[0091] The deposition liquid is:

[0092] A mixture of hydroxypropionic acid, boric acid, zirconium nitrate, aluminum nitrate, and phosphate;

[0093] The mass fraction of zirconium nitrate is 2%;

[0094] The mass fraction of aluminum nitrate is 1%;

[0095] The mass fraction of hydroxypropionic acid is 0.2%;

[0096] The mass fraction of boric acid is 1%;

[0097] The mass fraction of phosphate is 2.5%.

[0098] The phosphate is sodium phosphate or potassium phosphate.

[0099] The vacuum drying temperature was 60°C and the time was 10 hours.

[0100] The preparation method of calcined intercalated bentonite is as follows:

[0101] Firstly, cetyltrimethylammonium bromide is added into deionized water to prepare a cetyltrimethylammonium bromide solution with a mass fraction of 5%;

[0102] Bentonite was added to the hexadecyltrimethylammonium bromide solution, and the temperature was adjusted to 85°C under a vacuum of 0.1 Pa, and the mixture was stirred for 4 hours. Then, the mixture was discharged, filtered, washed, and dried at 100°C for 30 minutes to obtain intercalated bentonite.

[0103] calcining the intercalated bentonite obtained above to obtain calcined intercalated bentonite;

[0104] The calcination treatment temperature is 550° C. and the time is 35 minutes.

[0105] Example 4

[0106] A method for preparing a special coating for an inner cover of an electric rice cooker, wherein the surface of the inner cover of the electric rice cooker is pretreated, and then a specific coating is sprayed and cured to form the coating;

[0107] The pretreatment includes: cleaning and deposition;

[0108] The specific coating comprises the following ingredients by weight: 35 parts of water-based fluorocarbon resin, 3 parts of propylene glycol methyl ether acetate, 2 parts of hollow microspheres, 0.3 parts of silicone defoamer, 0.8 parts of acrylic leveling agent, 5 parts of calcined intercalated bentonite, 0.6 parts of propylene glycol methyl ether acetate, and 25 parts of water.

[0109] The inner cover of the rice cooker is 304 stainless steel;

[0110] The cleaning comprises: placing the inner cover of the rice cooker in acetone for cleaning for 15 minutes, and then drying it to a constant weight;

[0111] The deposition process is:

[0112] Connect the inner cover of the rice cooker to the negative pole of the power supply, connect the graphite to the positive pole of the power supply, then immerse the inner cover of the rice cooker and the graphite in the deposition liquid at the same time, start the power supply, and perform the deposition treatment for 10 minutes, then take it out, wash it with deionized water for 10 minutes, and then vacuum dry it to constant weight;

[0113] The deposition process was performed at a temperature of 58°C and a voltage of 8V.

[0114] The deposition liquid is:

[0115] A mixture of hydroxypropionic acid, boric acid, zirconium nitrate, aluminum nitrate, and phosphate;

[0116] The mass fraction of zirconium nitrate is 2%;

[0117] The mass fraction of aluminum nitrate is 1%;

[0118] The mass fraction of hydroxypropionic acid is 0.2%;

[0119] The mass fraction of boric acid is 1%;

[0120] The mass fraction of phosphate is 2.5%.

[0121] The phosphate is sodium phosphate or potassium phosphate.

[0122] The vacuum drying temperature was 60°C and the time was 10 hours.

[0123] The preparation method of calcined intercalated bentonite is as follows:

[0124] Firstly, cetyltrimethylammonium bromide is added into deionized water to prepare a cetyltrimethylammonium bromide solution with a mass fraction of 5%;

[0125] Bentonite was added to the hexadecyltrimethylammonium bromide solution, and the temperature was adjusted to 85°C under a vacuum of 0.1 Pa, and the mixture was stirred for 4 hours. Then, the mixture was discharged, filtered, washed, and dried at 100°C for 30 minutes to obtain intercalated bentonite.

[0126] calcining the intercalated bentonite obtained above to obtain calcined intercalated bentonite;

[0127] The calcination treatment temperature is 550° C. and the time is 35 minutes.

[0128] Comparative Example 1

[0129] Based on the technical solution of Example 1, the deposition process is not performed and the rest of the technical solutions remain unchanged.

[0130] Comparative Example 2

[0131] Based on the technical solution of Example 1, no calcined intercalated bentonite is added to the specific coating, and the rest of the technical solutions remain unchanged.

[0132] Comparative Example 3

[0133] On the basis of the technical solution of Example 1, the calcined intercalated bentonite in the specific coating is replaced with untreated bentonite, and the rest of the technical solutions remain unchanged.

[0134] test:

[0135] The water contact angles of the inner cover surfaces of the rice cookers after treatment in each group of the embodiments and comparative examples are as follows:

[0136] Table 1

[0137] Water contact angle° Example 1 156 Example 2 158 Example 3 153 Example 4 151 Comparative Example 2 128 Comparative Example 3 131

[0138] As can be seen from Table 1, the hydrophobicity of the coating formed on the surface of the inner cover of the rice cooker of the present invention is greatly improved (because the omission of the process steps of Comparative Example 1 has no obvious effect on the corresponding experiment in Table 1, the numerical value of Comparative Example 1 is omitted).

[0139] Adopt the cross-hatch method to test the adhesion of the embodiment and the comparative example:

[0140] Table 2

[0141] Adhesion / Grade Example 1 1 Example 2 1 Example 3 1 Example 4 1 Comparative Example 1 3 Comparative Example 2 2 Comparative Example 3 2

[0142] It can be seen from Table 2 that the special coating prepared by the present invention has higher adhesion.

[0143] Artificial aging test was performed on the coatings formed in the examples and comparative examples:

[0144] Table 3

[0145] Artificial aging resistance 3000h Example 1 No bubbles, cracks or peeling Example 2 No bubbles, cracks or peeling Example 3 No bubbles, cracks or peeling Example 4 No bubbles, cracks or peeling Comparative Example 1 No bubbles or peeling occurs, and micro cracks appear Comparative Example 2 No bubbles, peeling or cracks Comparative Example 3 No bubbles or peeling occurs, and micro cracks appear

[0146] It can be seen from Table 3 that the special coating prepared by the present invention has excellent aging resistance.

[0147] The above description is only a preferred embodiment of the present invention, but the present invention is not limited to the scope of implementation shown. Any changes made in accordance with the concept of the present invention, or modifications to equivalent embodiments with equivalent changes, which still do not exceed the spirit covered by the specification, should be within the protection scope of the present invention.

Claims

1. A method for preparing a special coating for an inner cover of an electric rice cooker, characterized in that: After pretreatment of the inner cover surface of the rice cooker, After spraying a specific coating and curing, it is formed; The pretreatment includes: cleaning and deposition; The specific coating comprises the following ingredients by weight: 30-35 parts of water-based fluorocarbon resin, 2-3 parts of film-forming aid, 1-2 parts of hollow microspheres, 0.1-0.3 parts of defoamer, 0.5-0.8 parts of leveling agent, 3-5 parts of calcined intercalated bentonite, 0.3-0.6 parts of propylene glycol methyl ether acetate, and 18-25 parts of water; the preparation method of the calcined intercalated bentonite is: Firstly, cetyltrimethylammonium bromide is added into deionized water to prepare a cetyltrimethylammonium bromide solution with a mass fraction of 5%; Add bentonite to the hexadecyltrimethylammonium bromide solution, adjust the temperature to 85°C under a vacuum of 0.1Pa, keep stirring for 4 hours, then discharge, filter, wash, and dry at 100°C for 30 minutes to obtain intercalated bentonite; The intercalated bentonite obtained above is calcined to obtain calcined intercalated bentonite; the calcination temperature is 550° C. and the time is 35 min; The inner cover of the rice cooker is made of 304 stainless steel; The cleaning process comprises: placing the inner cover of the rice cooker in acetone for cleaning for 10-15 minutes, and then drying it to a constant weight; The deposition process comprises: Connect the inner cover of the rice cooker to the negative pole of the power supply, connect the graphite to the positive pole of the power supply, then immerse the inner cover of the rice cooker and the graphite in the deposition liquid at the same time, start the power supply, and perform the deposition treatment for 10-16 minutes, then take it out, wash it with deionized water for 10 minutes, and then vacuum dry it to constant weight; The temperature of the deposition process was 58°C and the voltage was 6-8V; The sedimentation liquid is a mixture of hydroxypropionic acid, boric acid, zirconium nitrate, aluminum nitrate and phosphate; The mass fraction of zirconium nitrate is 2%; the mass fraction of aluminum nitrate is 1%; The mass fraction of hydroxypropionic acid is 0.2%; the mass fraction of boric acid is 1%; The mass fraction of phosphate is 2.5%.

2. The method for preparing a special coating for an inner cover of an electric rice cooker according to claim 1, characterized in that: The phosphate is sodium phosphate or potassium phosphate.

3. The method for preparing a special coating for an inner cover of an electric rice cooker according to claim 2, characterized in that: The vacuum drying temperature is 60°C and the time is 10 hours.

4. The method for preparing a special coating for an inner cover of an electric rice cooker according to claim 3, characterized in that: The film-forming aid is propylene glycol methyl ether acetate.

5. The method for preparing a special coating for an inner cover of an electric rice cooker according to claim 4, characterized in that: The defoamer is an organosilicon defoamer.

6. The method for preparing a special coating for an inner cover of an electric rice cooker according to claim 5, characterized in that: The leveling agent is an acrylic leveling agent.