CN113122108A

CN113122108A - Paint for woodware and preparation method thereof

Info

Publication number: CN113122108A
Application number: CN202110408244.3A
Authority: CN
Inventors: 毛鸿泽
Original assignee: Ningbo Colorful Household Technology Co ltd
Current assignee: Ningbo Colorful Household Technology Co ltd
Priority date: 2021-04-16
Filing date: 2021-04-16
Publication date: 2021-07-16

Abstract

The invention discloses a paint, in particular to a high-functionality woodenware paint composition and a preparation method of the paint for woodenware, wherein the composition is characterized by comprising 10 to 16 weight percent of curable epoxy resin, 58 to 64 weight percent of alumina compound, 10 to 15 weight percent of silicon carbide #240, 10 to 14 weight percent of silicon carbide #1200 and 2 to 5 weight percent of titanium dioxide. The invention solves the technical problem of improving the mechanical strength of the paint and maintaining a smooth surface state, and compared with expensive foreign advanced technology products, the invention provides equivalent performance with lower production cost.

Description

Paint for woodware and preparation method thereof

Technical Field

The invention relates to a paint, in particular to a paint for woodware and a preparation method of the paint for woodware.

Background

Paint is a chemical mixture coating that can be firmly covered on the surface of an object for protection, decoration, marking and other special purposes.

Paint is one of the indispensable materials in the home decoration process. In recent years, with the continuous improvement of people's life and the increasing rise of environmental protection calls, people have higher and higher requirements on furniture paint. Modern paints are becoming a multifunctional engineering material, an important industry in chemical industry, and are also widely used in our lives. The woodware paint can effectively protect wooden furniture, can form a firmly attached paint film on the surface of the furniture, and effectively prevent worm damage and mildew, thereby prolonging the service life.

The traditional wooden door has poor weather resistance, is easy to deform and crack and has poor dimensional stability when being used for a long time in an environment with large humidity and temperature change, and is easy to discolor, decay and have poor stability when being used in an environment with high humidity. Therefore, the traditional wooden door is covered with a paint coating layer with enough thickness so as to prevent the wooden door from easily generating discoloration, deformation and decay when being used in an environment with higher humidity and improve the dimensional stability of the wooden door.

However, the woodware paint on the market at present has unsatisfactory corrosion resistance and mechanical strength (bonding strength, compressive strength, wear resistance and the like).

Disclosure of Invention

The present inventors have developed paints having improved physical properties and functionality in order to overcome the above technical problems. As described below, the present inventors have found that when an organic polymer resin and an inorganic ceramic reinforcing agent are mixed in an optimum ratio, in this case, the mechanical strength of the paint, such as adhesive strength and abrasion resistance, can be improved, and a smooth surface state can be maintained, thereby completing the present invention.

Therefore, an object of the present invention is to provide paint for woodware, which can be coated regardless of the shape and size of woodware (cabinet doors and furniture) without moving the woodware during work, can be coated immediately on site, used at normal temperature, and a method for preparing the same, in order to improve abrasion resistance and optimize the content of ceramic reinforcing agent.

Another object of the present invention is to provide a high-performance paint for woodware and a method for preparing the paint for woodware using the same, in which an organic material prepared from a composite material and a ceramic reinforcing agent composition is used in an optimum ratio to improve mechanical strength such as adhesive strength, abrasion resistance, etc., in an economical manner.

The above object of the present invention can be achieved by a highly functional paint composition for woodware, which is characterized in that it comprises 10 to 16% by weight of a curable epoxy resin, 58 to 64% by weight of an alumina compound, 10 to 15% by weight of silicon carbide #240, 10 to 14% by weight of silicon carbide #1200 and 2 to 5% by weight of titanium dioxide, and a method for preparing the paint for woodware.

Wherein the alumina compound is alpha-alumina.

Wherein the silicon carbide is a mixture of #240 silicon carbide and #1200 silicon carbide in a weight ratio of 1: 1.

The invention provides a preparation method of a paint composition for woodware, which comprises the following steps: a) mixing a curable epoxy resin and titanium dioxide into a mixer and premixing to obtain a premix; b) putting the premix into a kneader to be stirred for the first time; c) adding #1200 silicon carbide into a kneader for secondary stirring; d) adding #240 silicon carbide into a kneader and stirring for three times; e) the alumina compound is added into a kneader to carry out quaternary stirring.

Wherein the first stirring step is stirred at 400 to 600rpm for 30 to 90 seconds, and the second to fourth stirring steps are stirred at 800 to 1200rpm for 20 to 40 seconds.

According to the paint composition for woodware and the method for preparing the same of the present invention, by obtaining an optimum ratio with respect to the composition of a composite material between a ceramic reinforcing material (inorganic material) and an epoxy resin (organic material), the composite material has the following characteristics: the maximum exertion of wear resistance and improvement of adhesive strength and wear resistance as a surface coating agent can improve mechanical strength and the like, and can provide a paint composition that can have a smooth surface state due to no crack generation, and a manufacturing process including a material selection technique can provide technical standards in consideration of workability, productivity and economy, and in the current market where foreign advanced technology products are in low monopoly in the domestic market, they can provide comparable performance at a lower production cost than expensive foreign advanced technology products by being developed using independent domestic techniques, and are expected to help replace imports, increase production channels and increase sales.

Drawings

FIG. 1 is a process flow diagram of a method of preparing a paint composition;

FIG. 2 is a graph showing the viscosity of an epoxy resin as a function of softening temperature;

FIG. 3 is an SEM photograph (magnification. times.100) of a sample.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments that can be derived from the embodiments of the present invention by a person of ordinary skill in the art are intended to fall within the scope of the present invention.

The present invention provides a paint composition for woodware, characterized in that it comprises 10 to 16% by weight of a curable epoxy resin, 58 to 64% by weight of an alumina compound, 10 to 15% by weight of silicon carbide #240, 10 to 14% by weight of silicon carbide #1200 and 2 to 5% by weight of titanium dioxide. More preferably, the curable epoxy resin composition comprises 10 to 11% by weight of a curing agent, 59 to 64% by weight of an alumina compound, 10 to 14% by weight of silicon carbide #240 and 10 to 14% by weight of silicon carbide #1200 and 2 to 5% by weight of titanium dioxide.

The curable epoxy resin may be any one selected from the group consisting of epoxy resins, polyacrylate resins, polyurethane resins, and polyolefin resins, but is not limited thereto.

The alumina compound, also called as alumina, shows the most content of the wear-resistant paint, is an important material for improving the wear resistance of the paint, and has high hardness and excellent wear resistance.

It may be any one selected from the group consisting of alpha-alumina, beta-alumina and gamma-alumina, but is not limited thereto.

Among alumina compounds, α -alumina is a product of the bayer process (melting point: 1999 to 2032 ℃), β -alumina has a stable form at high temperature (1500 ℃ or higher), and γ -alumina is trihydrate or α -hydrated alumina, obtained when heated, dehydrated and maintained at 900 ℃ and converted into α -alumina when set to 1000 ℃ or higher, which is also contained in a thin film formed when aluminum is cathodically oxidized.

The silicon carbide (SiC) is a powder filled between the pore poles of large-sized aluminum oxide, is used for an abrasive material, a resistor, a refractory material, and the like, and is an abrasion resistant material. In order to maximize the wear resistance, it is necessary to add a ceramic reinforcing agent in a maximum amount, and the average particle size of the silicon carbide (SiC) is preferably such that silicon carbide (SiC) #1200(14 + -) and #240(60 + -) are used in a ratio of 1: 1.

Silicon carbide is a material having a low purity but a strength sufficient for use as an abrasive, and is relatively inexpensive, in view of economy. In addition, since the basic stage does not yet include a color pigment, the size and color are different, and green and black are selected for color classification at the time of mixing.

Boron carbide (B) may be mixed or substituted, if desired, in addition to silicon carbide₄C) And is selected from the group consisting of silicon dioxide (SiO)₂) Any one of the group consisting of, but the invention is not limited thereto.

In addition, titanium dioxide has a large hiding power, so it is insoluble in almost all solvents, has a very high refractive index, and exhibits high scattering properties. Since it is a very stable material, hiding power, weather resistance, and resistance to heat or light discoloration can be improved. In the composition of the present invention, a powder having an average particle diameter of 0.36 μm is preferably selected and used.

As other additives, it plays an auxiliary role in each step from the manufacture to the curing (drying) of the paint to maintain durability, and various additives may be present according to functions.

Unlike conventional paints, the compositions of the present invention have a very high ceramic density. Therefore, a settling phenomenon occurs after a certain time passes after mixing, and most importantly, sagging occurs after coating and before curing in a working environment, resulting in poor marketability. To improve this, small amounts of anti-settling agents or dispersants may be added.

The invention also provides a preparation method of the paint composition for woodware, which comprises the following steps: a) mixing a curable epoxy resin and titanium dioxide into a mixer and premixing to obtain a premix; b) putting the premix into a kneader to be stirred for the first time; c) adding #1200 silicon carbide into a kneader for secondary stirring; d) adding #240 silicon carbide into a kneader and stirring for three times; e) the alumina compound was added to the kneader and stirred four times.

If the curable resin, titanium dioxide, silicon carbide and alumina compound are added out of order, some aggregation of the raw materials may occur regardless of the stirring conditions.

In addition, when stirring is performed by only one mixing, the components are not uniformly dispersed, and the curable resin has a phenomenon that a filler having a small particle diameter and titanium dioxide are deposited and reacted on the reaction vessel wall.

In order to produce the paint composition of the present invention, a general high-speed RPM stirrer for paint and coating production is not smoothly stirred due to viscosity during stirring, and is liable to cause abrasion and damage to production equipment.

Unlike conventional paint, coating and putty type plugging agents, it contains over 80% of high strength ceramic due to its characteristics, and a conventional stirrer causes severe abrasion to a stirring blade (impeller) and internal parts due to its high density. The surface and reinforcing material at the time of stirring vary in size from 1mm to 0.36 μm, and are high in density and not easy to mix, so that the following "kneader" equipment specifications need to be used in view of various types. The stirring blade has a horizontal structure rather than a vertical structure, has a heating function, and enables low-speed RPM control for high viscosity.

Examples of the invention

Test example 1: basic mixing experiment

To confirm the uniform dispersion and agitation of the ceramic in the resin, a basic mixing experiment was performed at substantially room temperature. The mixing order is resin, titanium dioxide, silica, aluminum oxide, mixing from small particle size. In this case, it is necessary to first disperse a small particle diameter in the resin in order to improve the stirring state.

1-1) Dispersion experiments using softening temperature (kneader)

An important consideration in the basic formulation is titanium dioxide (TiO)₂) The dispersion of (4), having a minimum particle diameter of 0.36 μm. Although it represents only 2% to 3% of the total weight, it is a very stable material and therefore must be uniformly dispersed, since it serves to improve hiding power, weather resistance and resistance to heat or light discoloration.

It can be easily dispersed by a Paste Mixer apparatus, but kneaders with different stirring principles are not easy.

To solve this problem, experiments were performed by first applying the softening temperature of the epoxy resin.

Epoxy resins have the phenomenon that the viscosity changes with the softening temperature (the temperature at which the enamel or frit begins to flow under certain conditions). The higher the temperature, the lower the viscosity, making the mixing of the reinforcing material easier. However, excessive heating causes precipitation of the ceramic reinforcing material, and therefore, it is necessary to maintain an appropriate temperature. Fig. 2 is a graph showing a viscosity change curve of an epoxy resin according to a softening temperature.

First, the mixture was heated with a kneader, and the epoxy resin was added. After a certain time, the titanium dioxide is mixed and stirred. The experiments were carried out at each temperature in this manner, but all the experiments were concentrated on the stirring blade, and the higher the temperature, the greater the possibility of the precipitation phenomenon occurring.

Test example 2: dispersion test in homogenizer

According to the experimental conclusion, as a result of preliminary experiments, separate Pre-mixing (Pre-Mix) was required, and satisfactory results were not obtained even with the dispersion of titanium dioxide in the resin, and tests were carried out with a homogenizer known as a "homogenizer" or "homogenizer".

The main function of the experimental device is that of a device which makes it possible to homogenize the heterogeneous state, as if it were just one substance, which is mainly used in cosmetic companies, mainly in products which require emulsification (lotions, creams, essences, etc.). The working principle is that when the impeller (wing) sucks in the contents by strong rotation at the bottom of the homomixer, it is sucked in through a tiny gap between the body and the impeller, and the particles fly out of the holes through the holes. When the dispersion device is in a low viscosity state, it should be smooth and have a small particle size.

2-1) titanium dioxide (TiO)₂) Dispersion test

The dispersion experiment of titanium dioxide was conducted at a laboratory temperature (23 ℃), and the experiment was conducted by changing the rotation speed and heating, and as a result, uniform dispersion was achieved without significant difference according to the variation factors.

2-2) Dispersion test of silicon carbide (SiC, #1200)

After the titanium dioxide dispersion experiment, the experiment was performed by mixing smaller #1200 sizes in the order of silicon carbide. By performing the test results at 300-550RPM and the heating variation, uniform dispersion was obtained with no significant difference according to the variation factors, but when the dispersion operation was stopped, a settling phenomenon immediately occurred, which was not suitable.

After establishing the mixing process, by repeating the experiment, the following phenomenon according to the mixing ratio was observed.

The above experimental results show that the content of the ceramic reinforcing agent is 88% at most, and when the content exceeds 88%, the excess amount of the ceramic reinforcing agent does not intersect with the resin, and becomes suspended matter. The curing agent has low specific gravity and low viscosity.

Examples 1 to 3 and comparative example 1: preparation of paint for woodware by using composite material

As shown in Table 1, a coating was prepared from a ceramic reinforcing agent (inorganic) alpha-alumina (particle size: 0.8 to 1.2mm), silicon carbide, titanium dioxide (particle size: 0.36 μm) and an organic epoxy resin for woodware. The unit is weight%.

Specifically, the curable epoxy resin and titanium dioxide were mixed in a mixer, then premixed to obtain a premix, and then the premix was introduced into a kneader, first stirred at 500rpm for 60 seconds, and then #1200 silicon carbide was added in the stirrer. Silicon carbide #240 and an alumina compound were sequentially added to the kneader, and a stirring step was performed at 1000rpm for 30 seconds between the addition steps to prepare a paint.

TABLE 1

Among them, samples A, B and C (examples 1 to 3) showing the optimum stirring conditions were selected to prepare test pieces for performance testing.

Test example 3: performance testing

Using the test pieces prepared in the above examples, test pieces for mechanical strength (bending strength, tensile strength, compressive strength) measurement and reliability test (cavitation, frictional wear, chipping resistance) were prepared for comparison with advanced technology products. Table 2 below is a performance evaluation index, table 3 is a mechanical strength test index, and table 4 is a reliability test index.

TABLE 2

TABLE 3

TABLE 4

On the other hand, three samples were prepared, samples a, B and C (examples 1 to 3) were cut out, respectively, and the porosity was required to be checked after photographing with an electron microscope. FIG. 3 is an SEM photograph (magnification. times.100) of a sample.

As a result of the test, all of the samples a, B and C were judged to have stable adhesion between materials having no pores in terms of porosity. (circle is a state where the ceramic beads are cut off).

The results of the performance index evaluation tests (adhesion strength, abrasion resistance, Shore D hardness, impact resistance) are shown in Table 5 below.

TABLE 5

As a result of testing samples of products developed according to embodiments of the present invention, and all met performance criteria.

In order to verify the performance of the test samples according to the examples, performance indexes as shown in table 6 were set.

TABLE 6

As a result of performance evaluation on the test samples, it was found that all five evaluation items were achieved.

A separate mechanical strength test was performed to compare the properties other than the performance index by using it as the result value of sample C having better abrasion resistance, and the results are shown in table 7.

TABLE 7

Samples a and B were measured twice and the last sample C was measured once. As a result of the test, sample C was the best (unit: MPa).

As a result of this test, when the advanced technology product and the developed product (sample C, example 3) were compared, both were found to have high mechanical strength. Particularly, the bending strength and the compression strength show excellent performance, and compared with the products of the foreign advanced technology, the difference is about 30 MPa.

Table 8 below shows the results of comparing the mechanical strength test results of the foreign advanced technology products and the developed products.

TABLE 8

As described above, the paint for woodware of the present invention has comparable or better properties than advanced-art products, and exhibits satisfactory properties even in terms of manufacturing methods and changes in raw materials to reduce production costs.

The present invention is not limited to the above-mentioned preferred embodiments, and any other products in various forms can be obtained by anyone in the light of the present invention, but any changes in the shape or structure thereof, which have the same or similar technical solutions as those of the present application, fall within the protection scope of the present invention.

Claims

1. A paint composition for woodware, which is characterized in that: comprising 10 to 16 weight percent of a curable epoxy resin, 58 to 64 weight percent of an alumina compound, 10 to 15 weight percent of silicon carbide #240, 10 to 14 weight percent of silicon carbide #1200 and 2 to 5 weight percent of titanium dioxide.

2. The paint composition for woodware according to claim 1, characterized in that: the alumina compound is alpha-alumina.

3. The paint composition for woodware according to claim 1, characterized in that: the silicon carbide is a mixture of #240 silicon carbide and #1200 silicon carbide in a 1: 1 weight ratio.

4. A method for preparing a paint composition for woodware according to any one of claims 1 to 3, characterized by comprising the steps of:

a) mixing a curable epoxy resin and titanium dioxide into a mixer and premixing to obtain a premix;

b) putting the premix into a kneader to be stirred for the first time;

c) adding #1200 silicon carbide into a kneader for secondary stirring;

d) adding #240 silicon carbide into a kneader and stirring for three times;

e) the alumina compound is added into a kneader to carry out quaternary stirring.

5. The method for preparing a paint composition for woodware according to claim 4, characterized in that: the first stirring step is stirred at 400 to 600rpm for 30 to 90 seconds, and the second to fourth stirring steps are stirred at 800 to 1200rpm for 20 to 40 seconds.