Silver-covering glass powder prepared by reducing ball milling, glass printing ink and preparation methods of silver-covering glass powder and glass printing ink

Abstract

The invention relates to silver-covering glass powder prepared by reductive ball milling, glass ink and a preparation method of the silver-covering glass powder and the glass ink. The silver-covering glass powder is prepared by ball-milling glass frits, a reducing medium and a reducing auxiliary agent through a reducing ball-milling process; the glass frit is prepared from the following substances in percentage by mass: 35-40% of silicon dioxide, 10-20% of boric acid, 10-20% of zinc oxide, 3-10% of calcium sulfate, 3-6% of titanium dioxide, 16-20% of carbonate, 1-3% of magnesium oxide, 1-3% of aluminum oxide and 1-3% of barium oxide. And the particle size of the silver-covering glass powder after ball milling is 5-15 [mu] m. Compared with the prior art, the reducing ball milling medium is introduced in the refining process of the glass powder and is matched with the reducing auxiliary agent to realize reduction treatment of the glass powder, the silver covering and acid resisting effects of the glass printing ink are considered, and the glass printing ink has the characteristics of low carbon, environment friendliness and simple process.

Description

Technical Field

[0001] The invention relates to the technical field of glass ink, and in particular to a silver-shielding glass powder made by reductive ball milling, glass ink and a preparation method thereof. Background Art

[0002] Glass materials prepared from lead-free and cadmium-free systems are often used to prepare glass inks, which can be applied to glassware, ceramic products or artworks, architectural glass, home appliance glass, etc., generally for decorative purposes and light shielding.

[0003] As for the glass ink used on automobile safety glass, it is a higher level application requirement. Automobile tempered glass ink has gradually emerged with the large-scale application of automobile glass. It is mainly processed on the edges of automobile glass through screen printing. In addition to the decorative beauty of general ink and the effective reduction of ultraviolet transmittance, it also has other performance requirements, such as anti-stickiness - tempering process trial, acid resistance, and shielding of heating wires - conductive silver paste on automobile glass.

[0004] At present, the overall level of domestic glass ink products is relatively low, and the market supply is mainly occupied by imported manufacturers Fulu and Zhuangxin. US Patent US6100209 proposes a method for preparing silver-shielding ink: a special high-temperature reduction treatment is performed on the pre-fired bismuth glass powder, and it is used to prepare glass ink with silver-shielding ability. This kind of glass ink not only uses relatively expensive bismuth raw materials, but also has an additional glass powder reduction process, which has defects in cost control and timeliness. Another method is to introduce additives into the ink formula, such as CN118222133A proposes to introduce an appropriate amount of bismuth oxide to inhibit silver migration, and US Patent US 663780 / 0211561 proposes to introduce silicon alloy as an additive to achieve the purpose of high-temperature sintering to shield silver paste. These methods can bring certain effects, but they cannot completely solve the silver-shielding problem, and will also increase costs, and will also have a negative impact on other properties of the ink, such as diluting the pigment coloring ability, affecting the acid resistance and chemical resistance of the glass ink.

[0005] Therefore, it is urgent to develop a new type of silver paste tempered glass ink that can take into account both silver-shielding effect and acid resistance. Summary of the invention

[0006] The purpose of the present invention is to overcome the defect of the above-mentioned prior art that it is difficult to take into account both the silver-shielding effect and the acid-resistant performance, and to provide a silver-shielding glass powder, glass ink and preparation method made by reductive ball milling.

[0007] The purpose of the present invention can be achieved by the following technical solutions:

[0008] The present invention first provides a silver-shielding glass powder made by reductive ball milling, wherein the silver-shielding glass powder is made by ball milling glass frit, a reductive medium and a reductive auxiliary agent through a reductive ball milling process;

[0009] The glass frit is composed of the following substances in mass fractions: 35-40% silicon dioxide, 10-20% boric acid, 10-20% zinc oxide, 3-10% calcium sulfate, 3-6% titanium dioxide, 16-20% carbonate, 1-3% magnesium oxide, 1-3% aluminum oxide, and 1-3% barium oxide;

[0010] The particle size of the silver-shielding glass powder after ball milling is 5-15 μm.

[0011] Furthermore, the glass frit is composed of the following substances in mass fractions: 40% silicon dioxide, 15% boric acid, 17% zinc oxide, 3% calcium sulfate, 4% titanium dioxide, 19% carbonate, 1-3% magnesium oxide, 1-3% aluminum oxide, and 1-3% barium oxide.

[0012] Furthermore, the carbonates include sodium carbonate, potassium carbonate and lithium carbonate, and the mass fractions of sodium carbonate, potassium carbonate and lithium carbonate in the glass frit are 6-8%, 6-9% and 3-5% respectively.

[0013] Furthermore, the reducing medium includes an aqueous solution of one or more of sodium oxalate, sucrose, carbon powder, and sulfite, and the concentration of the reducing substance in the aqueous solution is 4-10wt%.

[0014] Furthermore, the reducing aid includes one or more of silicon powder, molybdenum sulfide, sulfide alloy, and silicon-aluminum alloy.

[0015] Furthermore, the preparation method of the glass frit is: the mixed glass powder raw materials are evenly mixed by a mixer, kept warm at 1250-1350° C. for 30-40 minutes, and then the molten glass liquid is quenched and dried to obtain the glass frit.

[0016] Furthermore, the specific steps of the reductive ball milling process are: placing the reducing medium, glass frit, and reducing additive into a ball mill in a mass ratio of (4.5-5.5):(7-9):1 for ball milling, and drying and dispersing after ball milling to obtain the silver-shielding glass powder.

[0017] Furthermore, the mass ratio of the reducing medium, the glass frit and the reducing auxiliary agent is preferably 5:8:1.

[0018] Furthermore, the ball-to-material ratio of the ball mill is 5:(2-4), preferably 5:3.

[0019] Furthermore, the rotation speed of the ball mill is 300-500 rpm, preferably 400 rpm.

[0020] Furthermore, the ball milling time is 4-6h.

[0021] Furthermore, the particle size of the reducing agent is not strictly limited and can be comparable to the size of the glass frit.

[0022] The present invention also provides a glass ink comprising the above-mentioned silver-shielding glass powder, wherein the glass ink is composed of the following substances in mass fractions: 60-70% of the silver-shielding glass powder, 15-30% of the pigment, and 15-25% of the carrier.

[0023] Furthermore, the pigment includes one or more melanins such as copper chromium black, iron chromium black, iron manganese nickel chromium black, iron cobalt nickel black, etc., or other analogs including copper, chromium, iron, manganese, nickel, cobalt, or a compound of these types of melanins.

[0024] Furthermore, the particle size of the pigment is 1-2 μm, and the temperature resistance of the pigment is 800°C.

[0025] Furthermore, the carrier is varnish, and the varnish is composed of the following raw materials in mass fractions: 15-25% of resin, 1-2% of solvent dispersant, and the balance is solvent.

[0026] Furthermore, the resin includes one or more of ethyl cellulose, nitro cellulose or rosin.

[0027] Furthermore, the solvent includes one or more of terpineol, turpentine, and ethers.

[0028] Furthermore, the solvent dispersant is one or more of BYK-354, BYK-425 or BASF EFKA-4310.

[0029] The present invention also provides a method for preparing glass ink, which comprises the following steps: weighing silver-shielding glass powder, pigment and carrier and adding them into a disperser, kneading to obtain a rough mixture; grinding the rough mixture, and obtaining the glass ink when the ink fineness is below 10 μm.

[0030] Compared with the prior art, the present invention has the following beneficial effects:

[0031] (1) The present invention introduces reducing ball milling media during the refinement of the silver-shielding glass powder, and uses the fresh, high-energy particle surfaces generated when the glass particles are refined and crushed, as well as the instantaneous high energy brought about by the collision of particles during the ball milling process, in combination with a reducing aid to achieve reduction treatment of the glass powder, thereby taking into account the silver-shielding and acid-resistant effects of the glass ink.

[0032] (2) The glass ink system of the present invention is a lead-free, cadmium-free, and bismuth-free glass powder system, which not only meets the environmental protection requirements of automotive glass applications, but also greatly reduces the production cost.

[0033] (3) The reductive ball milling process of the present invention performs the reduction treatment of glass powder and the refinement process of glass powder simultaneously without adding any additional process, and has the characteristics of low carbon, environmental protection and simple process. DETAILED DESCRIPTION

[0034] The embodiments of the present invention are described in detail below. The following embodiments are implemented on the premise of the technical solution of the present invention, and detailed implementation methods and specific operation processes are given, but the protection scope of the present invention is not limited to the following embodiments.

[0035] Unless otherwise specified, the reagents, methods, instruments and equipment used in the present invention are conventional reagents, methods, instruments and equipment in the art. Unless otherwise specified, the reagents and materials used in the following examples are commercially available.

[0036] Embodiment 1:

[0037] The present embodiment provides a silver-shielding glass powder made by reductive ball milling and a glass ink containing the silver-shielding glass powder. The silver-shielding glass powder of the present embodiment is made from a glass frit by a reductive ball milling process. The composition of the glass frit of the present embodiment is 40% silicon dioxide, 15% boric acid, 17% zinc oxide, 3% calcium sulfate, 4% titanium dioxide, 7% sodium carbonate, 8% potassium carbonate, 4% lithium carbonate, 2% magnesium oxide, 3% aluminum oxide, and 1% barium oxide.

[0038] The composition ratios of the silver-shielding glass powder prepared by the reductive ball milling process in this embodiment are shown in Table 1. The specific preparation method is as follows:

[0039] (1) The glass powder raw materials are weighed according to the ratio, mixed evenly with a mixer, and then put into a crucible and kept at 1300°C for 35 minutes. The molten glass liquid is directly quenched with water and dried to obtain a glass frit.

[0040] (2) The reducing medium, glass frit, and reducing agent are placed in a high-energy ball mill at a mass ratio of 5:8:1, and ball milling is performed at a ball-to-material ratio of 5:3 at a rotation speed of 450 rpm for 4 hours. The glass powder obtained by ball milling is dried and dispersed. The particle size of the glass powder prepared by reducing ball milling is 3-12 μm, D 90 It is 9.0μm.

[0041] The ratio of the glass ink involved in this embodiment is shown in Table 2. The melanin involved is copper chrome black, which is heat-resistant to 800°C and has a particle size of 1-3μm. The ink varnish is composed of the following mass fractions: 5% ethyl cellulose (Rui Tai RT-N7), 5% ethyl cellulose (Luzhou North EC-N10), 10% rosin, 64% pine alcohol, 20% diethylene glycol butyl ether, and 1% dispersant (BYK-354). The method of varnishing the ink is: according to the mass ratio, add the resin, additives, etc. to the organic solvent, heat to 70-80°C, stir at a constant temperature until the resin is completely dissolved, and filter and remove impurities with a 300-400 mesh stainless steel mesh cloth to obtain the varnish as an organic carrier.

[0042] The preparation method of the glass ink in this embodiment is as follows: glass powder, melanin, varnish, etc. are added into a stirring and dispersing device according to a ratio, and kneaded to obtain a rough mixture. The rough mixture is transferred to a three-roll mill for grinding until the ink fineness is less than 10 μm.

[0043] The components of the glass frit, melanin and varnish in the following Examples 2, 3 and Comparative Examples 1-2 are the same as those in Example 1, and the preparation method of the glass ink is the same as that in Example 1. The proportions of the reducing ball milling components in each Example and Comparative Example are shown in Table 1.

[0044] Table 1 Component ratios of the reductive ball milling process in each embodiment and comparative example

[0045]

[0046]

[0047] The glass powder prepared in the above-mentioned embodiment and comparative example is used as raw material, and the ratio and performance test results of the glass ink finally prepared are shown in Table 2. Among them, the silver-shielding temperature range is the sintering temperature range in which the glass ink maintains a good shielding effect on the silver wire during sintering, and the larger the difference in the temperature range, the better the silver-shielding effect. The acid resistance test steps are: after sintering, the glass ink is placed at a constant temperature of 80°C, immersed in a 0.1N sulfuric acid aqueous solution for 72 hours, and the color development ability is observed.

[0048] Table 2 Proportions of glass ink and silver-shielding effect in various embodiments and comparative examples

[0049] project Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Glass powder 60％ 60％ 60％ 60％ 53.3％ additive 0 0 0 0 Silica powder (6.7%) melanin 20％ 20％ 20％ 20％ 20％ Varnish 20％ 20％ 20％ 20％ 20％ Silver shading temperature range (℃) 690-720 685-715 685-725 690-710 690-710 <![CDATA[0.1N H2SO4 80℃]]> ≥72h ≥72h ≥72h ≥72h ≥48h

[0050] In Examples 1-3, different reducing media and reducing additives were selected to obtain glass inks with good silver-shielding effect and excellent acid resistance. The difference in the silver-shielding temperature range was ≥30°C, and after being immersed in a high-temperature acidic solution for 72 hours, it was still able to maintain good adhesion and hardness without discoloration. Comparative Examples 1 and 2 did not introduce a reducing medium in the ball milling process, resulting in a silver-shielding temperature range difference of only 20°C. And Comparative Example 2 did not introduce a reducing additive in the ball milling process, resulting in poor acid resistance, which could only maintain good and no discoloration within 48 hours. At 72 hours, the adhesion weakened, the hardness decreased, and the ink layer began to turn white. It can be seen that the present invention can not only improve the silver-shielding effect of the glass ink by introducing a reducing ball milling process in the preparation of the glass ink, but also effectively improve the acid resistance of the glass ink, which is a significant improvement compared to ordinary ball milling.

[0051] The above description of the embodiments is to facilitate the understanding and use of the invention by those skilled in the art. It is obvious that those skilled in the art can easily make various modifications to these embodiments and apply the general principles described herein to other embodiments without creative work. Therefore, the present invention is not limited to the above embodiments, and improvements and modifications made by those skilled in the art based on the disclosure of the present invention without departing from the scope of the present invention should be within the scope of protection of the present invention.

Claims

1. A silver-shielding glass powder prepared by reductive ball milling, characterized in that: The silver-shielding glass powder is prepared by ball milling glass frit, reducing medium and reducing auxiliary agent through a reducing ball milling process; The glass frit is composed of the following substances by mass fraction: Composition: 35-40% silicon dioxide, 10-20% boric acid, 10-20% zinc oxide, 3-10% calcium sulfate, 3-6% titanium dioxide, 16-20% carbonate, 1-3% magnesium oxide, 1-3% aluminum oxide, 1-3% barium oxide; The particle size of the silver-shielding glass powder after ball milling is 5-15 μm.

2. The silver-shielding glass powder prepared by reductive ball milling according to claim 1, characterized in that: The glass frit is composed of the following substances by mass fraction: Composition: Silicon dioxide 40%, boric acid 15%, zinc oxide 17%, calcium sulfate 3%, titanium dioxide 4%, carbonate 19%, magnesium oxide 1-3%, aluminum oxide 1-3%, barium oxide 1-3%.

3. The silver-shielding glass powder prepared by reductive ball milling according to claim 1, characterized in that: The carbonates include sodium carbonate, potassium carbonate and lithium carbonate, and the mass fractions of sodium carbonate, potassium carbonate and lithium carbonate in the glass frit are 6-8%, 6-9% and 3-5% respectively.

4. The silver-shielding glass powder prepared by reductive ball milling according to claim 1, characterized in that: The reducing medium includes an aqueous solution of one or more of sodium oxalate, sucrose, carbon powder, and sulfite, and the concentration of the reducing substance in the aqueous solution is 4-10wt%.

5. The silver-shielding glass powder prepared by reductive ball milling according to claim 1, characterized in that: The reducing aid includes one or more of silicon powder, molybdenum sulfide, sulfide alloy, and silicon-aluminum alloy.

6. The silver-shielding glass powder prepared by reductive ball milling according to claim 1, characterized in that: The preparation method of the glass frit is as follows: The mixed glass powder raw materials are mixed evenly by using a mixer, and kept warm at 1250-1350° C. for 30-40 minutes. The molten glass liquid is then quenched and dried to obtain the glass frit.

7. The silver-shielding glass powder prepared by reductive ball milling according to claim 1, characterized in that: The specific steps of the reductive ball milling process are: The reducing medium, glass frit and reducing auxiliary agent are placed in a ball mill in a mass ratio of (4.5-5.5):(7-9):1 for ball milling. After ball milling, the silver-shielding glass powder is obtained by drying and dispersing.

8. The silver-shielding glass powder prepared by reductive ball milling according to claim 7, characterized in that: The ball-to-material ratio of the ball mill is 5:(2-4), the rotation speed of the ball mill is 300-500rpm, and the ball milling time is 4-6h.

9. A glass ink comprising the silver-shielding glass powder according to any one of claims 1 to 8, characterized in that: It is composed of the following substances by mass fraction: 60-70% silver-covering glass powder, 15-30% pigment, and 15-25% carrier; The pigment includes one or more melanin such as copper chrome black, iron chrome black, iron manganese nickel chrome black, iron cobalt nickel black, etc.; The carrier is varnish, which is composed of the following raw materials in mass fractions: 15-25% of resin, 1-2% of solvent dispersant, and the balance of solvent.

10. A method for preparing the glass ink according to claim 9, characterized in that: The preparation method comprises the following steps: The silver-shielding glass powder, the pigment and the carrier are weighed and added into a disperser, and kneaded to obtain a rough mixture; the rough mixture is ground until the ink fineness is below 10 μm to obtain the glass ink.

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