CN109897408B

CN109897408B - Durable coating for demolding of glass forming mold

Info

Publication number: CN109897408B
Application number: CN201910171696.7A
Authority: CN
Inventors: 孙家书; 张向飞; 臧运波; 邵梅玲; 蒲三旭; 翟滨
Original assignee: Shangqiu Normal University
Current assignee: Shangqiu Normal University
Priority date: 2019-03-07
Filing date: 2019-03-07
Publication date: 2020-09-04
Anticipated expiration: 2039-03-07
Also published as: CN109897408A

Abstract

The invention relates to a durable boron nitride coating for demolding a glass forming mold, which is prepared from the following raw materials in parts by weight: 30-50% of hexagonal boron nitride, 5-10% of graphene, 2-5% of silicon carbide, 5-20% of high-temperature binder, 0.2-1% of dispersing agent, defoaming agent and water, and performing ball milling for 8 hours. The coating disclosed by the invention adopts a water-based system, has no volatilization of harmful substances in the using process, is clean and environment-friendly, has good adhesiveness, and does not crack or peel. In addition, due to the addition of the graphene and the silicon carbide, the coating has super-strong lubricating capability, and glassware is easy to demould. Meanwhile, the silicon carbide can increase the difficulty of matrix crack propagation, the durability of the coating is enhanced, the coating has a relatively long service life, the cost is saved, and the economic benefit of enterprises is improved.

Description

Durable coating for demolding of glass forming mold

Technical Field

The invention belongs to the technical field of paint preparation, and particularly relates to a durable paint for demolding a glass forming mold.

Background

In the process of press-molding a glass product in a metal mold. The working temperature of the surface of the mold is generally 600-900 ℃, and the molten glass is easy to adhere to the surface of the mold at the temperature. Therefore, it is necessary to coat the working surface of the metal mold with a lubricant. The requirements of the production process of the glass product on the performance of the coating mainly comprise three aspects of lubricating capability, service life and pollution condition. With the development of coating technology, the problem of environmental pollution is primarily solved, and most of the existing coatings adopt environment-friendly inorganic materials as a collective material and water as a carrier. The release agents prepared by patents CN106167353A, CN108018114A and CN108793727A have the characteristics of small environmental pollution, high yield and the like.

Therefore, the current major problems are mainly focused on the first two aspects. The lubricating capability of the lubricating coating and the durability of the lubricating coating. And the reasonable selection of the base stock, the solid lubricant and the filler is the key for designing the durable lubricating coating.

The hexagonal boron nitride has high-temperature lubricating property, is an ideal material in the glass processing process, is beneficial to minimizing the surface defects of glass products, enables the glass products to be easier to demould, prolongs the service life of a mould/pressing mould and reduces the time required by cleaning the mould. Most glasses do not bond with boron nitride. The boron nitride coating can be applied to both hot and cold surfaces. The coating may be dried and then treated, smoothed and polished with a dry soft cotton cloth. Graphene is one of the materials with the best mechanical properties discovered so far, and the mechanical properties of a coating film can be greatly improved when the graphene is added into various functional coatings. Since the graphene nanoplatelets can enhance the adhesive force of the coating, the graphene coating has excellent wear resistance and scratch resistance, and manufacturers have developed a high-heat-conductivity and high-strength graphene coating for non-stick pan, and the coating has excellent high-temperature resistance and wear resistance. Silicon carbide has stable chemical properties, high thermal conductivity, low thermal expansion coefficient and good wear resistance, and is often used as a filling material. The silicon carbide exists in the boron nitride ceramic matrix in the form of a dispersed phase, and can reduce the stress of the crack tip. Cracks between boron nitride grains can deflect when encountering silicon carbide hard particles, and the deflection loses the energy of crack propagation and increases the difficulty of crack propagation. Therefore, the silicon carbide is added into the lubricating material, so that the lubricating property and the heat conducting property of the coating can be improved, the difficulty of matrix crack propagation can be increased, the durability of the material is enhanced, and the service life of the coating is prolonged.

Disclosure of Invention

Aiming at the current situation of glass mold stripping paint and the problems in the prior art, the invention provides durable paint for stripping glass forming molds.

In order to solve the technical problems, the invention adopts the following technical scheme:

the durable coating for demolding of the glass forming mold is characterized by being prepared from the following raw materials in parts by weight: 30-50% of hexagonal boron nitride, 5-10% of graphene, 2-5% of silicon carbide, 5-20% of high-temperature binder, 0.2-1% of dispersant, 0.3-1% of defoaming agent and water. The high-temperature binder may be any one selected from aluminum dihydrogen phosphate, aluminum sol, and aluminum sulfate. The dispersant may be one selected from sodium tripolyphosphate, tetrasodium diphosphate and sodium hexametaphosphate. The antifoaming agent may be any one selected from modesty antifoaming agents 6800, 6500 and 5500. The raw materials are mixed according to the weight ratio, and then ball milling is carried out for 8 hours under the condition that the ball material ratio is 10:1, so as to prepare the durable paint for demoulding the glass forming mould.

The invention has the beneficial effects that: the coating disclosed by the invention adopts a water-based system, has no volatilization of harmful substances in the using process, and is clean and environment-friendly. In addition, due to the addition of the graphene and the silicon carbide, the coating has super-strong lubricating capability, and glassware is easy to demould. Meanwhile, the silicon carbide can increase the difficulty of matrix crack propagation, so that the coating has a relatively long service life, the cost is saved, and the economic benefit of enterprises is improved.

Detailed Description

The present invention will be further described with reference to the following examples. It is to be understood that the following examples are illustrative only and are not intended to limit the scope of the invention, which is to be given numerous insubstantial modifications and adaptations by those skilled in the art based on the teachings set forth above.

Example 1

The durable coating for demolding the glass forming mold is prepared from the following raw materials in parts by weight: 30% of hexagonal boron nitride, 5% of silicon carbide, 2% of graphene, 5% of aluminum dihydrogen phosphate, 0.2% of sodium tripolyphosphate, 1% of a moderate antifoaming agent 6800, and the balance of water. The raw materials are mixed according to the weight ratio, and then ball milling is carried out for 8 hours under the condition that the ball material ratio is 10:1, so as to prepare the durable paint for demoulding the glass forming mould.

Example 2

The durable coating for demolding the glass forming mold is prepared from the following raw materials in parts by weight: 50% of hexagonal boron nitride, 10% of silicon carbide, 5% of graphene, 20% of aluminum sulfate, 0.2% of sodium hexametaphosphate, 0.3% of a moderate defoaming agent 6500 and the balance of water. The raw materials are mixed according to the weight ratio, and then ball milling is carried out for 8 hours under the condition that the ball material ratio is 10:1, so as to prepare the durable paint for demoulding the glass forming mould.

Example 3

The durable coating for demolding the glass forming mold is prepared from the following raw materials in parts by weight: 40% of hexagonal boron nitride, 8% of silicon carbide, 4% of graphene, 10% of alumina sol, 0.2% of tetrasodium diphosphate, 0.5% of a moderate defoamer 5500, and the balance of water. The raw materials are mixed according to the weight ratio, and then ball milling is carried out for 8 hours under the condition that the ball material ratio is 10:1, so as to prepare the durable paint for demoulding the glass forming mould.

Example 4

The durable coating for demolding the glass forming mold is prepared from the following raw materials in parts by weight: 40% of hexagonal boron nitride, 5% of silicon carbide, 3% of graphene, 20% of aluminum dihydrogen phosphate, 1.0% of sodium tripolyphosphate, 0.8% of a moderate antifoaming agent 6800, and the balance of water. The raw materials are mixed according to the weight ratio, and then ball milling is carried out for 8 hours under the condition that the ball material ratio is 10:1, so as to prepare the durable paint for demoulding the glass forming mould.

Comparative example 1

The durable coating for demolding the glass forming mold is prepared from the following raw materials in parts by weight: 30% of hexagonal boron nitride, 2% of graphene, 5% of aluminum dihydrogen phosphate, 0.2% of sodium tripolyphosphate, 1% of a moderate antifoaming agent 6800 and the balance of water. The raw materials are mixed according to the weight ratio, and then ball milling is carried out for 8 hours under the condition that the ball material ratio is 10:1, so as to prepare the durable paint for demoulding the glass forming mould.

Comparative example 2

The durable coating for demolding the glass forming mold is prepared from the following raw materials in parts by weight: 30% of hexagonal boron nitride, 5% of silicon carbide, 2% of graphite powder, 5% of aluminum dihydrogen phosphate, 0.2% of sodium tripolyphosphate, 1% of a moderate antifoaming agent 6800 and the balance of water. The raw materials are mixed according to the weight ratio, and then ball milling is carried out for 8 hours under the condition that the ball material ratio is 10:1, so as to prepare the durable paint for demoulding the glass forming mould.

The coatings obtained in the 4 examples and the 2 comparative examples are subjected to comparative tests in a certain glassware production company, and the coating friction coefficient, the service life, the glassware surface finish and the glassware yield are subjected to comparative tests, and the specific experimental comparison results are shown in the following table.

The comparison tests show that the obtained demoulding coating has lower friction coefficient, longer service life, better surface finish and higher yield.

The foregoing shows and describes the general principles and features of the present invention, together with the advantages thereof. It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, which are described in the specification and illustrated only to illustrate the principle of the present invention, but that various changes and modifications may be made therein without departing from the spirit and scope of the present invention, which fall within the scope of the invention as claimed. The scope of the invention is defined by the appended claims and equivalents thereof.

Claims

1. The durable coating for demolding the glass forming mold is characterized by being prepared from the following raw materials in parts by weight: 30-50% of hexagonal boron nitride, 5-10% of graphene, 2-5% of silicon carbide, 5-20% of high-temperature binder, 0.2-1% of dispersant, 0.3-1% of defoaming agent and the balance of water;

the high-temperature binder is any one of aluminum dihydrogen phosphate, aluminum sol or aluminum sulfate.

2. The durable coating for demolding glass-forming molds of claim 1, wherein: the dispersing agent is selected from sodium tripolyphosphate, tetrasodium diphosphate or sodium hexametaphosphate.

3. The durable coating for demolding glass-forming molds of claim 1, wherein: the antifoaming agent is selected from the group consisting of modesty antifoaming agents 6800, 6500 or 5500.

4. A method for preparing a durable coating for glass-forming mould release according to any of claims 1-3, characterized by the steps of: according to the weight ratio, 30-50% of hexagonal boron nitride, 5-10% of graphene, 2-5% of silicon carbide, 5-20% of high-temperature binder, 0.2-1% of dispersant, 0.3-1% of defoaming agent and the balance of water are added into a ball mill and ball-milled for 8 hours under the condition that the ball-to-material ratio is 10: 1.