Hot bending protection ink as well as preparation method and application thereof

Abstract

The invention belongs to the technical field of hot bending glass, and relates to hot bending protection ink as well as a preparation method and application thereof. The hot bending protection ink is prepared from the following components in parts by weight: 23 to 55 parts of solvent, 3 to 12 parts of water-based dispersion type resin, 25 to 55 parts of glass powder and 2 to 10 parts of pigment, the glass powder is prepared from the following components in parts by weight: 5 to 15 parts of SiO2, 60 to 90 parts of Bi2O3, 5 to 10 parts of B2O3, 8 to 15 parts of ZnO, 0.5 to 5 parts of lithium carbonate, 0.2 to 2.0 parts of sodium carbonate and 0.2 to 2 parts of potassium carbonate. According to the protective layer, the ink layer is sintered and formed before the glass is preheated, softened and hot-bent, a mold is only in direct contact with the protective layer when the glass is hot-bent, no trace is left on the surface of the glass, the viscosity of ink and the mold is small, and the hot-bending yield of the glass is increased. After being formed, the glass is soaked in a low-concentration acid solution, ink is completely dissolved due to poor acid resistance, and then the glass is cleaned.

Description

Technical Field

[0001] The present invention belongs to the technical field of heat - bent glass, and relates to a heat - bent protective ink, a preparation method thereof, and an application thereof. Background Art

[0002] Currently, 3D glass is generally used for the front and rear covers of high - end 3D mobile phones, and the transformation of glass from 2D to 3D is achieved by heat - bending at 500°C - 700°C. Especially for microcrystalline glass, due to its high hardness and strength, the heat - bending temperature will be higher, reaching 720 - 750°C. During this process, the four edges are the stress points, and the mold will press and damage the glass, leaving traces. In order to remove the traces left by heat - bending, a relatively hard brush is needed to polish, and it is easy to cause scrapping. Especially when the traces generated by heat - bending are deep, the yield of 3D glass is low and the cost is high.

[0003] The prior art CN 109401425 A discloses a protective ink for bending processing of curved glass. In parts by weight, the ink is composed of the following components: 50 - 90 parts of high - temperature resistant silicone resin, 10 - 20 parts of high - temperature resistant pigment, 5 - 15 parts of additive, and 2 - 8 parts of leveling agent. The ink has excellent high - temperature resistance and can withstand high temperatures of 600 - 1000°C. It can effectively protect the glass surface from being contaminated by impurities during the heat - bending processing of the glass panel. The subsequent cleaning is simple and residue - free, and only water or a sodium hydroxide aqueous solution with a concentration of 5 - 10% is required for cleaning, without the need for grinding and polishing.

[0004] The prior art CN 112624581 B discloses a 3D glass heat - bending process, which includes the following steps: printing a high - temperature resistant ink on the surface of 2D glass, performing heat - bending treatment after the surface of the high - temperature resistant ink is dried, and finally removing the ink. The raw materials of the high - temperature resistant ink include, in parts by weight: 50 - 60 parts of modified silicone resin solution, 20 - 30 parts of filler, and 2 - 5 parts of auxiliary agent; among them, in the preparation process of the modified silicone resin solution, tetrabutyl zirconate, tetrabutyl titanate, acetylacetone, and ethanol are mixed evenly, and a chelation reaction is carried out to obtain solution A; methyltrimethoxysilane, phenyltrimethoxysilane, and dimethyldimethoxysilane are hydrolyzed in an acidic ethanol aqueous solution to obtain solution B; solution A and solution B are mixed evenly and continue to be hydrolyzed, then the pH is adjusted to neutral, the precipitate is removed, and the solvent is evaporated to obtain a prepolymer; the prepolymer is dispersed in a diluent, and then trisilanol isobutyl POSS is added, and the temperature is raised for reaction to obtain a modified silicone resin solution.

[0005] However, both of the above - mentioned prior arts are inks, and the main body uses organic resin as the film - forming component, which has the problems of slow drying speed, high cost, and difficult cleaning of the organic resin. Summary of the Invention

[0006] The object of the present invention is to provide a hot-bending protective ink with low cleaning difficulty, as well as a preparation method and application thereof.

[0007] In order to achieve the above object, the present invention adopts the following technical solution:

[0008] A hot-bending protective ink, by weight, comprises: 23 - 55 parts of a solvent, 3 - 12 parts of an aqueous dispersion resin, 25 - 55 parts of glass powder, and 2 - 10 parts of a pigment;

[0009] The glass powder, by weight, comprises: 5 - 15 parts of SiO₂, 60 - 90 parts of Bi₂O₃, 5 - 10 parts of B₂O₃, 8 - 15 parts of ZnO, 0.5 - 5 parts of lithium carbonate, 0.2 - 2.0 parts of sodium carbonate, and 0.2 - 2 parts of potassium carbonate.

[0010] The main component of the hot-bending protective ink of the present invention is glass powder with poor acid resistance, which includes a large amount of Bi₂O₃, ZnO, lithium carbonate, sodium carbonate, and potassium carbonate with poor acid resistance, facilitating subsequent acid removal of the ink. Before the temperature of the glass surface in the hot-bending protective ink of the present invention reaches the temperature capable of hot bending (700 - 720 °C), at a temperature of 400 - 500 °C, the organic substances in the ink will decompose completely, forming water vapor and carbon dioxide and volatilizing, causing a large amount of glass powder to sinter, partially melt, and mix with some non-molten parts to bond into a film, covering the glass to prevent the glass from leaving marks during the hot-bending process, and having good protective performance. The film layer obtained by sintering the glass powder is easier to clean than the film layer of silicone resin, and has a better hot-bending protection effect.

[0011] In the glass powder, the molecular structure of silicon dioxide is mainly covalent bonds. With the Si atom as the center, four oxygen atoms form a stable and symmetric tetrahedral structure at the four vertices of a regular tetrahedron. Through the connection of the vertices and vertices, and the edges and edges of the Si - O tetrahedron, a basic and stable glass space network structure is formed, enabling the low-temperature glass powder to sinter into a film.

[0012] If the amount of silicon dioxide is too small, the Si - O tetrahedrons will be separated by other inorganic substances, unable to form a stable structure and unable to form a film; if the amount of silicon dioxide is too large, the network structure after film formation is mainly Si - O tetrahedrons, with good acid resistance, a high sintering temperature, and cannot be removed by dilute acid after hot bending.

[0013] The molecular structure of boron trioxide is mainly covalent bonds, forming a BO₃ layered structure. It cannot form a uniform melt with SiO₄ by itself, but with the addition of alkali metal oxides, the alkali metal oxides will release O in the molten state 2-The ions are provided to BO3 to transform into BO4, so that the structure changes from layered to tetrahedral frame structure, thus forming a stable glass body with SiO4. The melting point of boron trioxide is about 450℃, and the sintering temperature of the formed glass state is low. However, if the amount of boron trioxide is too much, it mainly exists in the BO3 layered structure and cannot form a stable glass body with SiO4; if the amount of boron trioxide is too little, the network structure formed is mainly Si-O tetrahedron, the sintering temperature is high, and it cannot be sintered in the preheating stage of hot bending.

[0014] Bismuth trioxide is mainly composed of ionic bonds. In the molten state, Bi 3+ It exists in a free state and cannot form glass alone. 3+ 、Si 4+ It exists in the form of isolated BO3 and SiO4 or multiple connected bodies. When the amount in the melt reaches a certain level, Bi 3+ , O 2- The accumulation of BO3 and SiO4 occurs in the encirclement of the polyhedron, which hinders its free migration. The oxygen charge at the top corner of the isolated or multiple connected bodies is unsaturated, and it must be connected with Bi outside the encirclement. 3+ connected to maintain electrical neutrality. 3+ The connection with BO and Si-O bonds in the same oxygen polyhedron is uneven, which leads to the distortion of BO3 and SiO4, thus forming an amorphous non-crystalline form of glass and reducing the sintering temperature of glass powder. In addition, bismuth trioxide can be dissolved in acid, which is conducive to acid dissolution after sintering. However, if there is too much bismuth trioxide, the Si-O tetrahedron will be occupied by free Bi 3+ Surrounded, unable to form a film; too little bismuth dioxide, high sintering temperature, unable to sinter during the preheating stage of the hot bending process.

[0015] The effect of zinc oxide is similar to that of bismuth trioxide, but zinc oxide can appropriately improve the alkali resistance of glass. Excessive use will also affect the stability of the glass.

[0016] Lithium carbonate, sodium carbonate and potassium carbonate decompose into corresponding oxides during the process of melting low-temperature glass powder. Their oxides are all network-external oxides. As disconnecting substances, they participate in the low-temperature glass powder and act as co-solvents to reduce the melting temperature of the low-temperature glass powder. However, if the amount is too much, it will reduce the thermal stability, chemical stability and mechanical strength of the low-temperature glass powder after sintering.

[0017] In a preferred embodiment, the glass powder comprises, by weight: 5-13 parts of SiO2, 63-87 parts of Bi2O3, 6-10 parts of B2O3, 9-13 parts of ZnO, 1-5 parts of lithium carbonate, 0.5-2.0 parts of sodium carbonate, and 0.5-2 parts of potassium carbonate.

[0018] In one preferred embodiment, the glass powder, by weight, comprises: 5-11 parts of SiO2, 65-85 parts of Bi2O3, 8-10 parts of B2O3, 10-13 parts of ZnO, 2-5 parts of lithium carbonate, 0.5-1.8 parts of sodium carbonate, and 0.5-1.8 parts of potassium carbonate.

[0019] In one preferred embodiment, by weight, the solvent comprises 3-15 parts of a cosolvent and 20-40 parts of a main solvent. The cosolvent includes one or more of methanol, ethanol, propanol, ethylene glycol, glycerol, propylene glycol methyl ether, and ethylene glycol methyl ether; the main solvent is water.

[0020] The cosolvent in the ink can help the resin disperse better in water, which is beneficial to the stability of the ground powder particles in water.

[0021] Deionized water in the sintering ink serves as the main solvent of the ink, reducing the viscosity of the ink, improving the grinding efficiency, and at the same time enabling more convenient adjustment of the inkjet printing effect.

[0022] In one preferred embodiment, the waterborne dispersible resin includes one or more of waterborne polyurethane, waterborne acrylic resin, waterborne phenolic resin, waterborne rosin resin, and styrene-maleic anhydride-ammoniated resin.

[0023] In the molecular structure of the waterborne dispersible resin of the present invention, there are strong polar groups such as hydroxyl, carboxyl, and amino groups. During the sanding process of the sintering ink, it can anchor on the surface of the powder, enabling the powder particles with a suitable fineness after sanding to be stably dispersed in the solvent, forming a stable dispersion. At the same time, the waterborne dispersible resin can endow the sintering ink with good rheology, facilitating the shaping after inkjet printing and forming a film after drying, and improving its water resistance.

[0024] In one preferred embodiment, the pigment includes one or more of iron oxide black, cobalt black, copper chromium black, and copper manganese black.

[0025] The pigment provides the color after sintering for easy detection.

[0026] In one preferred embodiment, the hot bending protection ink, by weight, comprises: 26-55 parts of a solvent, 4-12 parts of a waterborne dispersible resin, 28-55 parts of glass powder, and 2-9 parts of a pigment.

[0027] In one preferred embodiment, the hot bending protection ink, by weight, comprises: 30-55 parts of a solvent, 5-12 parts of a waterborne dispersible resin, 30-52 parts of glass powder, and 2-8 parts of a pigment.

[0028] In one preferred embodiment, the particle size of the thermoforming protection ink is 200 - 800 nm.

[0029] The ink layer formed by the thermoforming protection ink with such particle size is relatively delicate, thin and dense, will not leave indentations during the thermoforming process, and can effectively prevent the anti - sticking ink from penetrating into the dried and sintered ink after being sprayed on it.

[0030] In one preferred embodiment, the preparation method of the glass powder comprises the following steps:

[0031] Mix the components of the glass powder evenly, then carry out high - temperature melting, rapid cooling, drying and grinding to obtain the glass powder.

[0032] In one preferred embodiment, the process of high - temperature melting is as follows: control the heating rate at 1 - 2 °C / min, after reaching 800 - 900 °C, hold for 30 - 50 min, then with a heating rate of 1 - 2 °C / min, heat up to 1200 - 1300 °C and hold for 2 - 3 h.

[0033] If the heating rate is too slow, the time is long and the energy consumption is high; if the heating rate is too fast, the temperature of the whole powder is uneven too much, which will cause the uniformity of the film layer to be seriously reduced.

[0034] In one preferred embodiment, the process of rapid cooling is as follows: quickly pour the product after heat preservation into ice water to make it crack into small glass slag.

[0035] In one preferred embodiment, the medium added during the grinding process is zircon beads.

[0036] In one preferred embodiment, the medium includes zircon beads of various different sizes.

[0037] In one preferred embodiment, the medium includes zircon beads of large, medium and small sizes. Among them, the diameter of the large zircon beads is 18 - 22 mm, the diameter of the medium zircon beads is 3.8 - 4.0 mm, and the diameter of the small zircon beads is 0.8 - 1.0 mm; the mass ratio of the large, medium and small zircon beads is 1:3 - 5:5 - 7.

[0038] In one preferred embodiment, the addition amount of the medium during the grinding process is 1 - 2 times the mass of the raw material.

[0039] In one preferred embodiment, the grinding time is 6 - 10 h.

[0040] In one preferred embodiment, the diameter of the material after grinding is less than 45 μm.

[0041] Based on the same inventive concept, the present invention also claims to protect a thermoformed protective layer, including an ink layer, which is obtained by inkjet printing the thermoformed protective ink on the glass surface and then drying it at 120 - 150 °C for 30 - 60 s.

[0042] When the temperature is low, the evaporation rate of water in the ink is slow, which affects the production efficiency; when the temperature is high, the energy consumption is also high.

[0043] In one preferred embodiment, the thickness of the ink layer is 1 - 2 μm.

[0044] In one preferred embodiment, the thermoformed protective layer further includes an anti - sticking layer, which is disposed on the surface of the ink layer.

[0045] In one preferred embodiment, the dry film thickness of the anti - sticking layer is 50 - 200 nm.

[0046] If the thickness after drying is too thin, it cannot play the role of anti - sticking; if it is too thick, the entire protective layer will be too thick, affecting the thermoforming effect.

[0047] In one preferred embodiment, the anti - sticking layer is obtained by drying anti - sticking ink at 120 - 150 °C for 30 - 60 s.

[0048] In one preferred embodiment, the anti - sticking ink, by weight, includes: 60 - 90 parts of neutral silica sol, 5 - 15 parts of water - soluble PVA resin, and 5 - 30 parts of deionized water.

[0049] In one preferred embodiment, in the neutral silica sol, the silica content is 20 - 35 wt%, the particle size is 10 - 150 nm, and the content of Na2O is less than 0.3 wt%.

[0050] Neutral silica sol is a colloidal solution formed by hydrolysis and polycondensation reactions with silicic acid or silicate as the basic unit. Its pH value is neutral, ranging from 6.5 to 7.5. Compared with acidic silica sol and basic silica sol, the particle size of silica sol (particle size: 10 - 150 nm) is small, and a very delicate anti - sticking layer can be formed after sintering. Moreover, the neutral system will not react with the sintering ink during the drying process and penetrate into the ink, affecting the performance of the sintering ink. However, under the action of H + or OH - the particulate silica in the silica sol will deeply penetrate into the sintering ink. During the sintering process, some silica particles participate in the network system formed after sintering, affecting the subsequent ink removal.

[0051] In one preferred embodiment, the degree of alcoholysis of the water-soluble PVA resin is ≥88%, the pH value is 6.5 - 7, and the molecular weight is 1000 - 12000.

[0052] If the molecular weight of the water-soluble PVA resin is too small, the drying performance is poor, and it is easy to stick to the hand after drying. If the molecular weight is too large, the water solubility is poor, or it can dissolve in hot water but will precipitate at room temperature, affecting the inkjet printing performance. If the degree of alcoholysis of the water-soluble PVA resin is too small, the water solubility is poor. If the pH value of the water-soluble PVA resin exceeds the range, it will cause neutral silica sol to penetrate into the sintered ink.

[0053] In one preferred embodiment, the anti-sticking ink, by weight, comprises: 60 - 88 parts of neutral silica sol, 6 - 15 parts of water-soluble PVA resin, and 8 - 30 parts of deionized water.

[0054] In one preferred embodiment, the anti-sticking ink, by weight, comprises: 60 - 85 parts of neutral silica sol, 8 - 15 parts of water-soluble PVA resin, and 10 - 30 parts of deionized water.

[0055] Put the glass after inkjet printing the sintered ink and the anti-sticking ink and drying them separately into a mold, raise the temperature programatically to 700 - 720 °C, then cool down and anneal to obtain a 3D glass with good performance, and then dissolve the ink with dilute acid and clean it.

[0056] Before the temperature on the glass surface reaches the thermoforming temperature of 700 - 720 °C, within the temperature range of 400 - 500 °C, the organic matter in the sintered ink will decompose completely to form water vapor and carbon dioxide and volatilize. The neutral silica sol in the anti-sticking ink leaves a nanoscale silica layer due to the volatilization of water. Since the melting point of silica is above 1600 °C, it floats on the surface of the sintered ink and will not participate in the subsequent process of the sintered ink forming a film. During the entire thermoforming process of the glass, there will be no melting phenomenon on the surface, effectively preventing the adhesion between the sintered ink and the mold during the thermoforming of the glass.

[0057] In the present invention, a very thin layer of sintered ink is printed on the edge of the glass to be thermoformed by inkjet printing and cured. At the same time, a layer of anti-sticking ink is printed on the surface of the ink layer. During the curing process, the water volatilizes and the organic matter decomposes to form a nanoscale silica anti-sticking layer on the surface of the ink. The two-layer structure then uses the heat during the thermoforming temperature rise process to sinter and melt to form an inorganic protective ink layer, superimposing the inorganic anti-sticking layer formed by silica sol, which can not only adhere well to the glass but also prevent sticking to the mold during thermoforming.

[0058] Before the protective layer of the present invention is preheated and softened and thermally bent, the ink layer has been sintered and formed. When the glass is thermally bent, the thermal bending force is transmitted through the ink layer to the glass to deform the glass into the desired shape. The mold only directly contacts the protective layer, and the glass will not be directly stressed and damaged. At the same time, the particle size of the ink is very small, forming a very dense structure, which is basically the same as the surface state of the glass and will not leave marks on the glass surface. The viscosity of the ink and the mold is small, improving the yield of glass thermal bending. After the glass is formed, it is immersed in a low-acid solution. The ink has poor acid resistance and is completely dissolved, and then it can be cleaned up. Description of the Drawings

[0059] Figure 1 Photo of Example 1 after thermal bending without acid pickling and washing.

[0060] Figure 2 Photo of Example 2 after thermal bending without acid pickling and washing.

[0061] Figure 3 Photo of Example 3 after thermal bending without acid pickling and washing.

[0062] Figure 4 Photo of Example 4 after thermal bending without acid pickling and washing.

[0063] Figure 5 Photo of Example 5 after thermal bending without acid pickling and washing.

[0064] Figure 6 Photo of Example 6 after thermal bending without acid pickling and washing.

[0065] Figure 7 Photo of Examples 1-6 after thermal bending and acid pickling and washing.

[0066] Figure 8 Photo of Comparative Example 1 after thermal bending without polishing.

[0067] Fig. 9 Photo of Comparative Example 2 after thermal bending without polishing.

[0068] Fig.10 Photo of Comparative Example 3 after acid pickling and washing with residues remaining after thermal bending.

[0069] Fig.11 Photo of Comparative Example 3 after being bruised after complete acid pickling and washing after thermal bending.

[0070] Fig.12 Photo comparing the waveform of poor spraying and normal spraying in Comparative Example 4.

[0071] Fig.13 Photo of Comparative Example 5 with the mold sticking during thermal bending.

[0072] Fig.14 Photo of Comparative Example 5 without residues remaining after pickling and washing.

[0073] Fig.15 Photo of the handling and dropping for Comparative Example 6.

[0074] Fig.16 Photo of the remaining after the degreasing and washing for Comparative Example 7.

[0075] Fig.17 Photo of the indentation after the acid degreasing and washing are completed after the hot bending for Comparative Example 7.

[0076] Fig.18 Photo of the poor waveform of the spraying for Comparative Example 8. Specific Embodiments

[0077] The present invention is not limited to the following specific embodiments. Those of ordinary skill in the art can implement the present invention in other various specific embodiments according to the content disclosed in the present invention, or any simple changes or modifications made by adopting the design structure and idea of the present invention fall within the protection scope of the present invention. It should be noted that, without conflict, the embodiments in the present invention and the features in the embodiments can be combined with each other.

[0078] The materials or processes involved in the present invention are as follows:

[0079] Glass: 0.8mm mobile phone glass.

[0080] Printing: Printing one layer with a 300 - 350 - mesh polyester screen.

[0081] Surface drying: 10 - 20 min at 120 - 150 °C.

[0082] Hot bending: 30 min at 700 - 720 °C.

[0083] The pH value of the neutral silica sol is 6.5 - 7.5, the silica content is 20 - 35%, the particle size is 10 - 150 nm, and the Na2O content < 0.3%.

[0084] The molecular weight range of the water - soluble PVA resin is 1000 - 12000, the alcoholysis degree ≥ 88%, and the pH value is 6.5 - 7.0.

[0085] Example 1

[0086] Step 1: Weigh the components in Table 1 according to the ratio with a precision electronic balance, accurate to 0.001 g, and then mix the various powders evenly with a kneader.

[0087] Table 1 Glass Powder Formula Table

[0088] Material Name Weight supplier <![CDATA[SiO2]]> 6.5 Chemical reagents <![CDATA[Bi2O3]]> 70 Chemical reagents <![CDATA[B2O3]]> 8 Chemical reagents ZnO 10 Chemical reagents Lithium carbonate 3 Chemical reagents Sodium carbonate 1.2 Chemical reagents Potassium carbonate 1.3 Chemical reagents

[0089] Add the uniformly mixed powder materials into a high-temperature melting furnace, heat them, and control the temperature increase at a rate of 1 - 2 °C / min. When the temperature reaches 800 °C, keep it warm for 30 min, then increase the temperature to 1200 °C at a rate of 1 - 2 °C / min, keep it warm for 2 h, and quickly pour it into an ice-water mixture to make it crack into small glass slag, then filter and dry it.

[0090] Add the dried glass slag into a corundum grinding jar, add zirconium beads, and the ratio of zirconium beads is: 0.8 - 1.0 mm / 3.8 - 4.0 mm / 20 mm = 6 / 4 / 1. The total amount of zirconium beads is 1.5 times that of the glass slag. Grind it on a planetary mill for 8 h, and sieve it with a 325-mesh sieve to obtain sample A.

[0091] Step 2: According to the weight ratio in Table 2, mix deionized water, propanol, and waterborne rosin resin uniformly. While stirring, add A and copper chromite black, stir evenly, pump it into a horizontal sand mill, and perform reflux sanding. Add 0.6 - 0.8 mm zirconium beads into the sand mill, and the volume is 50 - 70% of the inner cavity of the sand mill. After sanding for 4 h, take samples to measure the particle size until the particle size distribution D100 of the sanding is < 800 nm.

[0092] Table 2 Sintering Ink Formula Table

[0093]

[0094]

[0095] Step 3: Completely dissolve the water-soluble PVA resin and deionized water in Table 3, add neutral silica sol, and stir evenly.

[0096] Table 3 Anti-Sticking Ink Formula Table

[0097] Material Name Weight supplier Neutral silica sol 75 Better New Materials Deionized water 19 self made Water-soluble PVA resin 6 Japan Kuraray

[0098] Print the sintering ink in Table 2 onto the periphery of the mobile phone 2D glass to be thermally bent through an inkjet printing device, dry it at 120 - 150 °C for 30 s, and the dry film thickness is 1 - 2 μm. The ink adheres well to the glass and will not fall off during the handling process.

[0099] After drying, spray a layer of the anti-sticking ink in Table 3 onto the dried sintering ink, dry it at 120 - 150 °C for 50 s, and the dry film thickness is 150 nm.

[0100] Put the glass sprayed with ink into a mold, increase the temperature programatically to 700 - 720 °C, and then decrease the temperature programatically for annealing to obtain a 3D glass with good performance. For the photo of the 3D glass without acid pickling and washing after thermal bending, see Figure 1 . Then dissolve the ink with 0.1N dilute hydrochloric acid for 1 - 2 min, and wash it with water for 30 - 60 s.

[0101] Example 2

[0102] Step 1: Weigh the components in Table 4 according to the ratio using a precision electronic balance, accurate to 0.001 g, and then mix the powders evenly with a kneader.

[0103] Table 4 Glass Powder Formula Table

[0104] Material Name Weight supplier <![CDATA[SiO2]]> 7 Chemical reagents <![CDATA[Bi2O3]]> 65.5 Chemical reagents <![CDATA[B2O3]]> 8.5 Chemical reagents ZnO 12 Chemical reagents Lithium carbonate 3.5 Chemical reagents Sodium carbonate 1.7 Chemical reagents Potassium carbonate 1.8 Chemical reagents

[0105] Add the evenly mixed powders into a high-temperature melting furnace, heat, and control the heating rate at 1 - 2 °C / min. When the temperature reaches 800 °C, hold for 30 min, then increase the temperature to 1200 °C at a heating rate of 1 - 2 °C / min, hold for 2 h, and quickly pour it into an ice-water mixture to make it crack into fine glass slag, filter, and dry.

[0106] Add the dried glass slag into a corundum grinding jar, add zirconium beads, and the ratio of zirconium beads is: 0.8 - 1.0 mm / 3.8 - 4.0 mm / 20 mm = 6 / 4 / 1. The total amount of zirconium beads is 1.5 times that of the glass slag. Grind on a planetary mill for 8 h, and sieve with a 325-mesh sieve to obtain Sample A.

[0107] Step 2: Mix deionized water, propylene glycol methyl ether, and waterborne rosin resin evenly according to the weight ratio in Table 5. While stirring, add A and copper chromite black, stir evenly, pump it into a horizontal sand mill, and perform reflux sanding. Add 0.6 - 0.8 mm zirconium beads into the sand mill, with a volume of 50 - 70% of the inner cavity of the sand mill. After sanding for 4 h, take a sample to measure the particle size until the particle size distribution D100 < 800 nm after sanding.

[0108] Table 5 Sintering Ink Formula Table

[0109]

[0110]

[0111] Step 3: Completely dissolve the water-soluble PVA resin and deionized water in Table 6, add neutral silica sol, and stir evenly.

[0112] Table 6 Anti-sticking Ink Formula Table

[0113] Material Name Weight supplier Neutral silica sol 75 Better New Materials Deionized water 15 self made Water-soluble PVA resin 10 Japan Kuraray

[0114] Print the sintering ink in Table 5 onto the periphery of the mobile phone 2D glass to be thermally bent through an inkjet printing device, dry at 120 - 150 °C for 40 s, and the dry film thickness is 1 - 2 μm. The ink adheres well to the glass and will not fall off during handling.

[0115] After the ink is dried, spray a layer of anti-sticking ink in Table 6 on the dried sintered ink, dry it at 120 - 150 °C for 40 s, and the dry film thickness is 100 nm.

[0116] Put the glass sprayed with ink into the mold, raise the temperature programatically to 700 - 720 °C, and then cool it programatically and anneal it to obtain a 3D glass with good performance. For the photo of the 3D glass without acid pickling and washing after hot bending, see Figure 2 Then dissolve the ink with 0.1N dilute hydrochloric acid for 1 - 2 min, and wash it with water for 30 - 60 s.

[0117] Example 3

[0118] Step 1: Weigh the components in Table 7 according to the ratio with a precision electronic balance to an accuracy of 0.001 g, and then mix the powders evenly with a kneader.

[0119] Table 7 Glass powder formula

[0120] Material Name Weight supplier <![CDATA[SiO2]]> 8.5 Chemical reagents <![CDATA[Bi2O3]]> 66.5 Chemical reagents <![CDATA[B2O3]]> 8.7 Chemical reagents ZnO 10 Chemical reagents Lithium carbonate 2.9 Chemical reagents Sodium carbonate 1.8 Chemical reagents Potassium carbonate 1.6 Chemical reagents

[0121] Add the evenly mixed powders into a high-temperature melting furnace, heat it, and control the heating rate at 1 - 2 °C / min. When the temperature reaches 800 °C, hold it for 30 min, then raise the temperature at a rate of 1 - 2 °C / min to 1200 °C, hold it for 2 h, and quickly pour it into an ice-water mixture to make it crack into small glass slag, filter it, and dry it.

[0122] Add the dried glass slag into a corundum grinding jar, add zircon beads, and the ratio of zircon beads is: 0.8 - 1.0 mm / 3.8 - 4.0 mm / 20 mm = 6 / 4 / 1. The total amount of zircon beads is 1.5 times that of the glass slag. Grind it on a planetary mill for 8 h and sieve it with a 325-mesh sieve to obtain Sample A.

[0123] Step 2: According to the weight ratio in Table 8, mix deionized water, alcohol, and waterborne polyurethane resin in Table 8 evenly. While stirring, add A and copper chromite black, stir evenly, pump it into a horizontal sand mill, and perform reflux sanding. Add 0.6 - 0.8 mm zircon beads to the sand mill, and the volume is 50 - 70% of the inner cavity of the sand mill. After sanding for 4 h, take a sample to measure the particle size until the particle size distribution D100 < 800 nm.

[0124] Table 8 Sintered ink formula

[0125]

[0126]

[0127] Step 3: Completely dissolve the water-soluble PVA resin and deionized water in Table 9, add neutral silica sol, and stir evenly.

[0128] Table 9 Anti-sticking Ink Formula Table

[0129] Material Name Weight supplier Neutral silica sol 72 Better New Materials Deionized water 20.5 self made Water-soluble PVA resin 7.5 Japan Kuraray

[0130] Print the sintering ink in the made Table 8 around the 2D glass of the mobile phone to be thermally bent through an inkjet printing device, dry it at 120 - 150 °C for 45 s, with a dry film thickness of 1 - 2 μm. The ink adheres well to the glass and will not fall off during handling.

[0131] After the ink is dried, spray a layer of anti-sticking ink in Table 9 on the dried sintering ink, dry it at 120 - 150 °C for 50 s, with a dry film thickness of 150 nm.

[0132] Put the glass sprayed with ink into a mold, raise the temperature programatically to 700 - 720 °C, then cool down programatically and anneal to obtain a 3D glass with good performance. For the photo of the non-acid pickling and washing after thermal bending, see Figure 3 Then dissolve the ink with 0.1N dilute hydrochloric acid for 1 - 2 min, and wash it with water for 30 - 60 s.

[0133] Example 4

[0134] Step 1: Weigh the components in Table 10 according to the ratio with a precision electronic balance, accurate to 0.001 g, and then mix the powders evenly with a kneader.

[0135] Table 10 Glass Powder Formula

[0136] Material Name Weight supplier <![CDATA[SiO2]]> 10 Chemical reagents <![CDATA[Bi2O3]]> 65 Chemical reagents <![CDATA[B2O3]]> 9 Chemical reagents ZnO 11 Chemical reagents Lithium carbonate 2.8 Chemical reagents Sodium carbonate 1.4 Chemical reagents Potassium carbonate 0.8 Chemical reagents

[0137] Add the evenly mixed powders into a high-temperature melting furnace, heat and control the temperature increase at a rate of 1 - 2 °C / min. When the temperature reaches 800 °C, hold for 30 min, then increase the temperature at a rate of 1 - 2 °C / min to 1200 °C, hold for 2 h, quickly pour it into an ice-water mixture to make it crack into small glass slag, filter, and dry.

[0138] Add the dried glass slag into a corundum grinding tank, add zircon beads, and the ratio of zircon beads is: 0.8 - 1.0 mm / 3.8 - 4.0 mm / 20 mm = 6 / 4 / 1. The total amount of zircon beads is 1.5 times that of the glass slag. Grind on a planetary grinder for 8 h, and sieve with a 325-mesh sieve to obtain Sample A.

[0139] Step 2: According to the weight ratio in Table 11, mix deionized water, ethylene glycol methyl ether, and waterborne phenolic resin evenly. While stirring, add A and copper chromite black, stir evenly, pump it into a horizontal sand mill, and perform reflux sanding. Add 0.6 - 0.8 mm zircon beads into the sand mill, with a volume of 50 - 70% of the inner cavity of the sand mill. After sanding for 4 h, take a sample to measure the particle size until the particle size distribution D100 < 800 nm after sanding.

[0140] Table 11 Sintering Ink Formulation Table

[0141]

[0142]

[0143] Step 3: Completely dissolve the water-soluble PVA resin and deionized water in Table 12, add neutral silica sol, and stir evenly.

[0144] Table 12 Anti-sticking Ink Formulation Table

[0145] Material Name Weight supplier Neutral silica sol 72 Better New Materials Deionized water 20 self made Water-soluble PVA resin 8 Japan Kuraray

[0146] Print the sintering ink in Table 11 that has been prepared onto the four sides of the mobile phone 2D glass to be thermally bent through an inkjet printing device, dry it at 120 - 150 °C for 40 s, the dry film thickness is 1 - 2 μm, the ink adheres well to the glass and will not fall off during handling.

[0147] After the ink is dried, spray a layer of the anti-sticking ink in Table 12 onto the dried sintering ink, dry it at 120 - 150 °C for 30 s, and the dry film thickness is 80 nm.

[0148] Put the glass sprayed with ink into a mold, increase the temperature programatically to 700 - 720 °C, then decrease the temperature programatically and anneal to obtain a 3D glass with good performance. For the photo of the thermally bent glass without acid pickling and washing, see Figure 4 . Then dissolve the ink with 0.1N dilute hydrochloric acid for 1 - 2 min and wash it with water for 30 - 60 s.

[0149] Example 5

[0150] Prepare each raw material according to the following table and prepare the glass sprayed with ink. The operation steps are the same as those in Example 1.

[0151] Table 13 Glass Powder Formulation Table

[0152] Material Name Weight supplier <![CDATA[SiO2]]> 9 Chemical reagents <![CDATA[Bi2O3]]> 67 Chemical reagents <![CDATA[B2O3]]> 9.5 Chemical reagents ZnO 10 Chemical reagents Lithium carbonate 2.2 Chemical reagents Sodium carbonate 0.7 Chemical reagents Potassium carbonate 1.6 Chemical reagents

[0153] Table 14 Sintering Ink Formulation Table

[0154] Material Name Weight supplier Deionized water 30 self made Propylene glycol methyl ether 9 Chemical reagents Water-based acrylic resin 8 Guangdong Keding A 45 Chemical reagents Copper Chrome Black 8 Golden Ring

[0155] Table 15 Anti-sticking Ink Formulation Table

[0156] Material Name Weight supplier Neutral silica sol 77 Better New Materials Deionized water 13 self made Water-soluble PVA resin 10 Japan Kuraray

[0157] Put the glass sprayed with ink into a mold, increase the temperature programatically to 700 - 720 °C, then decrease the temperature programatically and anneal to obtain a 3D glass with good performance. For the photo of the thermally bent glass without acid pickling and washing, see Figure 5。Then dissolve the ink with 0.1N dilute hydrochloric acid for 1 - 2 minutes, and wash it with water for 30 - 60 seconds.

[0158] Example 6

[0159] Prepare each raw material according to the following table, and prepare the glass sprayed with ink. The operation steps are the same as those in Example 1.

[0160] Table 16 Glass powder formula table

[0161] Material Name Weight supplier <![CDATA[SiO2]]> 11 Chemical reagents <![CDATA[Bi2O3]]> 66 Chemical reagents <![CDATA[B2O3]]> 9 Chemical reagents ZnO 10 Chemical reagents Lithium carbonate 2.5 Chemical reagents Sodium carbonate 0.7 Chemical reagents Potassium carbonate 0.8 Chemical reagents

[0162] Table 17 Sintering ink formula table

[0163]

[0164] Table 18 Anti - sticking ink formula table

[0165] Material Name Weight supplier Neutral silica sol 80 Better New Materials Deionized water 10 self made Water-soluble PVA resin 10 Japan Kuraray

[0166] Put the glass sprayed with ink into the mold, raise the temperature program - matically to 700 - 720 °C, then cool it program - matically and anneal to obtain a 3D glass with good performance. The photo of the un - acid - washed and heat - bent glass is shown in Figure 6 。Then dissolve the ink with 0.1N dilute hydrochloric acid for 1 - 2 minutes, and wash it with water for 30 - 60 seconds.

[0167] The photos of the acid - washed and heat - bent glasses in Examples 1 - 6 are shown in Figure 7 。

[0168] Comparative Example 1

[0169] Without printing the protective ink, directly heat - bend it. The results are shown in Figure 8 。

[0170] Comparative Example 2

[0171] Step 1: Weigh the components in Table 19 according to the ratio with a precision electronic balance, accurate to 0.001 g, and then mix the powders evenly with a kneader.

[0172] Table 19 Glass powder formula table

[0173] Material Name Weight supplier <![CDATA[SiO2]]> 20 Chemical reagents <![CDATA[Bi2O3]]> 55 Chemical reagents <![CDATA[B2O3]]> 7 Chemical reagents ZnO 13 Chemical reagents Lithium carbonate 3 Chemical reagents Sodium carbonate 1 Chemical reagents Potassium carbonate 1 Chemical reagents

[0174] Add the evenly - mixed powders into a high - temperature melting furnace, heat it, control the heating rate at 1 - 2 °C / min, keep the temperature at 800 °C for 30 minutes, then raise the temperature to 1200 °C at a rate of 1 - 2 °C / min, keep it for 2 hours, quickly pour it into an ice - water mixture to make it crack into small glass slag, filter, and dry.

[0175] Add the dried glass slag into a corundum grinding jar, and add zirconium beads. The ratio of zirconium beads is: 0.8 - 1.0 mm / 3.8 - 4.0 mm / 20 mm = 6 / 4 / 1. The total amount of zirconium beads is 1.5 times that of the glass slag. Grind for 8 h on a planetary mill, and sieve with a 325-mesh sieve to obtain Sample A.

[0176] Step 2: Mix silicone resin, pseudocumene, and cetane evenly according to the weight ratio in Table 2. Then add A, mica, titanium dioxide, and copper chromite black, and stir evenly. Grind on a three-roll mill until the fineness is ≤ 5 μm to obtain B.

[0177] Table 20 Ink Formula Table

[0178] Material Name Weight parts supplier Silicone resin 35 Anhui Aiyota Tetramethylbenzene 10 Hualun Chemical Hexadecane 8 Chemical reagents A 34 self made Mica 4 Grey Titanium dioxide 3 DuPont Copper Chrome Black 6 Golden Ring

[0179] Print the ink well on the edge of the glass to be heat-bent with a 300-mesh screen, heat at 180 °C for 30 min, with a dry film thickness of 3 - 7 μm. After complete curing, perform heat bending. The results are shown in Fig. 9 。

[0180] Comparative Example 3

[0181] Step 1: Weigh the components in Table 21 according to the ratio with a precision electronic balance, accurate to 0.001 g. Then mix the various powder materials evenly with a kneader.

[0182] Table 21 Glass Powder Formula Table

[0183] Material Name Weight supplier <![CDATA[SiO2]]> 20 Chemical reagents <![CDATA[Bi2O3]]> 60 Chemical reagents <![CDATA[B2O3]]> 7 Chemical reagents ZnO 10 Chemical reagents Lithium carbonate 0.5 Chemical reagents Sodium carbonate 1.2 Chemical reagents Potassium carbonate 1.3 Chemical reagents

[0184] Add the evenly mixed powder materials into a high-temperature melting furnace, heat, and control the heating rate at 1 - 2 °C / min. When the temperature reaches 800 °C, hold for 30 min, then increase the temperature to 1200 °C at a rate of 1 - 2 °C / min, hold for 2 h, and quickly pour it into an ice-water mixture to make it crack into small glass slags, filter, and dry.

[0185] Add the dried glass slag into a corundum grinding jar, and add zirconium beads. The ratio of zirconium beads is: 0.8 - 1.0 mm / 3.8 - 4.0 mm / 20 mm = 6 / 4 / 1. The total amount of zirconium beads is 1.5 times that of the glass slag. Grind for 8 h on a planetary mill, and sieve with a 325-mesh sieve to obtain Sample A.

[0186] Step 2: Mix deionized water, propanol, and water-based rosin resin evenly according to the weight ratio in Table 22. While stirring, add A and copper chromite black, stir evenly, pump it into a horizontal sand mill, and perform reflux sanding. Add 0.6 - 0.8 mm zirconium beads into the sand mill, with a volume of 50 - 70% of the inner cavity of the sand mill. After sanding for 4 h, take samples to measure the particle size until the particle size distribution D100 < 800 nm.

[0187] Table 22 Sintering Ink Formulation Table

[0188]

[0189]

[0190] Step 3: Completely dissolve the water-soluble PVA resin and deionized water in Table 23, add neutral silica sol, and stir evenly.

[0191] Table 23 Anti-Sticking Ink Formulation Table

[0192] Material Name Weight supplier Neutral silica sol 75 Better New Materials Deionized water 19 self made Water-soluble PVA resin 6 Japan Kuraray

[0193] Print the sintering ink in Table 22 onto the periphery of the mobile phone 2D glass to be thermally bent through an inkjet printing device, dry it at 120 - 150 °C for 30 s, with a thickness of 1 - 2 μm. The ink adheres well to the glass and will not fall off during handling.

[0194] After drying, spray a layer of the anti-sticking ink in Table 23 onto the dried sintering ink, dry it at 120 - 150 °C for 50 s, and the dry film thickness is 150 nm.

[0195] Put the glass sprayed with ink into a mold, raise the temperature programatically to 700 - 720 °C, then cool down programatically and anneal to obtain 3D glass. Then dissolve the ink with 0.1N dilute hydrochloric acid for 1 - 2 min, and wash it with water for 30 - 60 s.

[0196] Because the sintering temperature of the glass powder is high, it only sinters when the glass starts to be thermally bent, and it cannot play a good protective role, resulting in indentation, and the residue after washing and removal is serious. The results are shown in Fig.10 (residue after washing and removal) and Fig.11 (indentation).

[0197] Comparative Example 4

[0198] Step 1: Weigh the components in Table 24 according to the ratio with a precision electronic balance, accurate to 0.001 g, and then mix the various powder materials evenly with a kneader.

[0199] Table 24 Glass Powder Formulation Table

[0200] Material Name Weight supplier <![CDATA[SiO2]]> 6.5 Chemical reagents <![CDATA[Bi2O3]]> 70 Chemical reagents <![CDATA[B2O3]]> 8 Chemical reagents ZnO 10 Chemical reagents Lithium carbonate 3 Chemical reagents Sodium carbonate 1.2 Chemical reagents Potassium carbonate 1.3 Chemical reagents

[0201] Add the evenly mixed powder materials into a high-temperature melting furnace, heat, control the heating rate at 1 - 2 °C / min, keep the temperature at 800 °C for 30 min, then raise the temperature at a heating rate of 1 - 2 °C / min to 1200 °C, keep it for 2 h, quickly pour it into an ice-water mixture to make it crack into small glass slag, filter, and dry.

[0202] Add the dried glass slag into a corundum grinding jar, and add zirconium beads. The ratio of zirconium beads is: 0.8 - 1.0 mm / 3.8 - 4.0 mm / 20 mm = 6 / 4 / 1. The total amount of zirconium beads is 1.5 times that of the glass slag. Grind for 8 h on a planetary mill, and sieve through a 325-mesh sieve to obtain Sample A.

[0203] Step 2: According to the weight ratio in Table 25, mix deionized water, propanol, and waterborne rosin resin evenly. While stirring, add A and copper chromite black, stir evenly, pump into a horizontal sand mill, and perform reflux sanding. Add 0.6 - 0.8 mm zirconium beads into the sand mill, with a volume of 50 - 70% of the inner cavity of the sand mill. After sanding for 4 h, take samples to measure the particle size until the particle size distribution D100 of the sanding is 1050 ± 50 nm.

[0204] Table 25 Sintering Ink Formula Table

[0205]

[0206]

[0207] Completely dissolve the water-soluble PVA resin and deionized water in Table 26, and add neutral silica sol, then stir evenly.

[0208] Table 26 Anti-Sticking Ink Formula Table

[0209] Material Name Weight supplier Neutral silica sol 75 Better New Materials Deionized water 19 self made Water-soluble PVA resin 6 Japan Kuraray

[0210] Print the prepared sintering ink in Table 25 around the mobile phone 2D glass to be thermally bent through an inkjet printing device, dry at 120 - 150 °C for 30 s, and the dry film thickness is 1 - 2 μm. The ink adheres well to the glass and will not fall off during handling.

[0211] After drying, spray a layer of anti-sticking ink in Table 26 on the dried sintering ink, dry at 120 - 150 °C for 50 s, and the dry film thickness is 150 nm.

[0212] The particle size of the sintering ink is 1000 nm ± 50. The particle size of the sintering ink is relatively large, which is easy to clog the nozzle and cannot be printed normally. Its spraying waveform is as Fig.12 shown on the left, where Fig.12 the right is the waveform of the normal particle size, and there are obvious differences between the two.

[0213] Comparative Example 5

[0214] Step 1: Weigh the components in Table 27 according to the ratio with a precision electronic balance, accurate to 0.001 g, and then mix the powders evenly with a kneader.

[0215] Table 27 Glass Powder Formula Table

[0216] Material Name Weight supplier <![CDATA[SiO2]]> 6.5 Chemical reagents <![CDATA[Bi2O3]]> 70 Chemical reagents <![CDATA[B2O3]]> 8 Chemical reagents ZnO 10 Chemical reagents Lithium carbonate 3 Chemical reagents Sodium carbonate 1.2 Chemical reagents Potassium carbonate 1.3 Chemical reagent

[0217] Add the uniformly mixed powder materials into a high-temperature melting furnace, heat them, and control the temperature increase rate at 1 - 2 °C / min. When the temperature reaches 800 °C, keep it warm for 30 min, then increase the temperature to 1200 °C at a rate of 1 - 2 °C / min, keep it warm for 2 h, and quickly pour it into an ice-water mixture to make it crack into small glass slag, then filter and dry it.

[0218] Add the dried glass slag into a corundum grinding jar, add zirconium beads, and the ratio of zirconium beads is: 0.8 - 1.0 mm / 3.8 - 4.0 mm / 20 mm = 6 / 4 / 1. The total amount of zirconium beads is 1.5 times that of the glass slag. Grind it on a planetary mill for 8 h, and sieve it with a 325-mesh sieve to obtain Sample A.

[0219] Step 2: Mix deionized water, propanol, and water-based rosin resin evenly according to the weight ratio in Table 28. While stirring, add A and copper chromite black, stir evenly, pump it into a horizontal sand mill, and perform reflux sanding. Add 0.6 - 0.8 mm zirconium beads into the sand mill, and the volume is 50 - 70% of the inner cavity of the sand mill. After sanding for 4 h, take a sample to measure the particle size until the particle size distribution D100 < 800 nm after sanding.

[0220] Table 28 Sintering Ink Formula Table

[0221]

[0222]

[0223] Print the sintering ink in Table 28 onto the periphery of the mobile phone 2D glass to be thermally bent through an inkjet printing device, dry it at 120 - 150 °C for 30 s, and the dry film thickness is 1 - 2 μm. The ink adheres well to the glass and will not fall off during the handling process.

[0224] Put the glass sprayed with ink into a mold, increase the temperature programatically to 700 - 720 °C, then decrease the temperature programatically for annealing to obtain 3D glass, and then dissolve the ink with 0.1 N dilute hydrochloric acid for 1 - 2 min, and wash it with water for 30 - 60 s.

[0225] Because only the sintering ink layer is made and no anti-adhesive layer is made, the sintering ink will soften during the thermal bending of the glass and adhere to the mold, resulting in a shortened service life of the mold. The obtained results are shown in Figure 13 (adhering to the mold) and Figure 14 (no residue after washing and annealing).

[0226] Comparative Example 6

[0227] Table 29 Anti-adhesive Ink Formula Table

[0228] Material name Parts by weight Supplier Neutral silica sol 75 Baitex New Materials Deionized water 19 Self-made Water-soluble PVA resin 6 Kuraray Japan

[0229] The anti - sticking ink in Table 29 was printed around the 2D glass of the mobile phone to be thermally bent through an ink - jet printing device, dried at 120 - 150 °C for 50 s, and the dry film thickness was 150 nm. The ink could not adhere well to the glass and peeled off seriously during handling.

[0230] Only the anti - sticking ink layer was made. Because the glass surface is very smooth, there are relatively few organic substances in the anti - sticking ink and the silica powder left after drying the neutral silica sol has no adhesion to the smooth glass at all. After the whole anti - sticking ink is dried, its adhesion on the smooth glass surface is poor and it is easy to peel off during handling. The obtained results are shown in Figure 15 (peeling off).

[0231] Comparative Example 7

[0232] Step 1: Weigh the components in Table 30 according to the ratio with a precision electronic balance to 0.001 g, and then mix the powders evenly with a kneader.

[0233] Table 30 Glass Powder Formula Table

[0234] Material name Parts by weight Supplier <![CDATA[SiO2]]> 6.5 Chemical reagent <![CDATA[Bi2O3]]> 70 Chemical reagent <![CDATA[B2O3]]> 8 Chemical reagent ZnO 10 Chemical reagent Lithium carbonate 3 Chemical reagent Sodium carbonate 1.2 Chemical reagent Potassium carbonate 1.3 Chemical reagent

[0235] The evenly - mixed powders were added to a high - temperature melting furnace, heated, and the temperature was increased at a rate of 1 - 2 °C / min. When the temperature reached 800 °C, it was held for 30 min, then the temperature was increased to 1200 °C at a rate of 1 - 2 °C / min and held for 2 h, and then quickly poured into an ice - water mixture to make it crack into small glass slag, filtered, and dried.

[0236] The dried glass slag was added to a corundum grinding jar, and zircon beads were added. The ratio of zircon beads was: 0.8 - 1.0 mm / 3.8 - 4.0 mm / 20 mm = 6 / 4 / 1, and the total amount of zircon beads was 1.5 times that of the glass slag. It was ground on a planetary mill for 8 h and sieved through a 325 - mesh sieve, Sample A.

[0237] Step 2: According to the weight ratio in Table 31, deionized water, propanol, and water - based rosin resin were mixed evenly. While stirring, A and copper chromite black were added and stirred evenly, then pumped into a horizontal sand mill for reflux sanding. 0.6 - 0.8 mm zircon beads were added to the sand mill, and the volume was 50 - 70% of the inner cavity of the sand mill. After sanding for 4 h, samples were taken to measure the particle size until the particle size distribution D100 < 800 nm after sanding.

[0238] Table 31 Sintering Ink Formula Table

[0239]

[0240]

[0241] Completely dissolve the water-soluble PVA resin and deionized water in Table 32, add neutral silica sol, and stir evenly.

[0242] Anti-sticking ink formulation table in Table 32

[0243] Material name Parts by weight Supplier Acidic silica gel 75 Baitex New Materials Deionized water 19 Self-made Water-soluble PVA resin 6 Kuraray Japan

[0244] Among them, the performance indicators of the acidic silica sol are pH value: 2 - 4, silica content: 30 - 31%, particle size: 10 - 150 nm, Na2O: <0.006%, and the performance indicators of the water-soluble PVA resin are molecular weight range of 1000 - 12000, alcoholysis degree ≥ 88%, pH value: 6.5 - 7.

[0245] Print the sintering ink in Table 31 onto the four sides of the mobile phone 2D glass to be thermally bent through an inkjet printing device, dry at 120 - 150 °C for 30 s, the dry film thickness is 1 - 2 μm, and the ink adheres well to the glass and will not fall off during handling.

[0246] After drying, spray a layer of anti-sticking ink in Table 32 onto the dried sintering ink, dry at 120 - 150 °C for 50 s, and the dry film thickness is 150 nm.

[0247] Put the glass sprayed with ink into a mold, raise the temperature program - matically to 700 - 720 °C, then lower the temperature program - matically for annealing to obtain 3D glass, and then dissolve the ink with 0.1N dilute hydrochloric acid for 1 - 2 min, and wash with water for 30 - 60 s.

[0248] During the drying process of the acidic silica sol, due to the penetration of H + , part of the acidic silica sol will penetrate into the sintering ink layer, resulting in an increase in the sintering temperature of the sintering ink at some positions. The sintering temperature is close to the thermal bending temperature of the glass. At the beginning of thermal bending, a dense protective layer is not formed, and this position will be damaged. At the same time, due to the penetration of the acidic silica sol, the proportion of silica in the sintering ink at this position increases, and it is easy to have residues after washing. The results of the thermally bent glass are shown in Figure 16 (washing residue) and Figure 17 (damage).

[0249] Comparative example 8

[0250] Step 1: Weigh the components in Table 33 according to the ratio with a precision electronic balance to an accuracy of 0.001 g, and then mix the various powder materials evenly with a kneader.

[0251] Glass powder formulation table in Table 33

[0252] Material name Parts by weight Supplier <![CDATA[SiO2]]> 6.5 Chemical reagent <![CDATA[Bi2O3]]> 70 Chemical reagent <![CDATA[B2O3]]> 8 Chemical reagent ZnO 10 Chemical reagent Lithium carbonate 3 Chemical reagent Sodium carbonate 1.2 Chemical reagent Potassium carbonate 1.3 Chemical reagent

[0253] Add the uniformly mixed powder materials into a high-temperature melting furnace, heat them, and control the temperature increase rate at 1 - 2 °C / min. When the temperature reaches 800 °C, hold for 30 min, then increase the temperature to 1200 °C at a rate of 1 - 2 °C / min, hold for 2 h, and quickly pour it into an ice-water mixture to make it crack into small glass slag, then filter and dry it.

[0254] Add the dried glass slag into a corundum grinding jar, add zirconium beads, and the ratio of zirconium beads is: 0.8 - 1.0 mm / 3.8 - 4.0 mm / 20 mm = 6 / 4 / 1. The total amount of zirconium beads is 1.5 times that of the glass slag. Grind for 8 h on a planetary grinder, and sieve with a 325-mesh sieve to obtain sample A.

[0255] Step 2: Mix deionized water, propanol, and water-based rosin evenly according to the weight ratio in Table 34. While stirring, add A and copper chromite black, stir evenly, pump it into a horizontal sand mill, and perform reflux sanding. Add 0.6 - 0.8 mm zirconium beads into the sand mill, and the volume is 50 - 70% of the inner cavity of the sand mill. After sanding for 4 h, take samples to measure the particle size until the particle size distribution D100 of the sanding is < 800 nm.

[0256] Table 34 Sintering Ink Formula Table

[0257] Material name Parts by weight Supplier Deionized water 6 Self-made Propanol 1 Chemical reagent Water-based rosin 70 Wuzhou Richeng Forest Chemical Industry A 15 Chemical reagent Copper chromite black 8 Golden Ring

[0258] Completely dissolve the water-soluble PVA resin and deionized water in Table 35, and add neutral silica sol, then stir evenly.

[0259] Table 35 Anti-sticking Ink Formula Table

[0260] Material name Parts by weight Supplier Neutral silica sol 75 Baitex New Materials Deionized water 19 Self-made Water-soluble PVA resin 6 Kuraray Japan

[0261] Print the sintering ink in Table 34 onto the periphery of the mobile phone 2D glass to be thermally bent through an inkjet printing device, and dry it at 120 - 150 °C for 30 s.

[0262] Print the sintering ink in Table 34 onto the periphery of the mobile phone 2D glass to be thermally bent through an inkjet printing device. Because the proportion of water-based rosin in the sintering ink is high and the ink viscosity is very high, it cannot be printed normally, the printing is prone to ink breakage, and the printed ink cannot be completely dried at this temperature. The printed waveform photo is shown in Figure 18 。

[0263] The performance test results of the sintering ink and anti-sticking ink prepared in Examples 1 - 6 and Comparative Examples 1 - 8 are as follows.

[0264] Table 36 Test Results of Examples 1 - 6

[0265]

[0266] Table 37 Test Results of Comparative Examples 1-8

[0267]

[0268]

[0269] As can be seen from Table 36 and Table 37: After the sintering ink and the anti-sticking ink of the present invention are used in combination, there is no need for polishing after the hot bending of the mobile phone 3D glass, and the yield is high, which can reduce the cost of manufacturers.

[0270] Secondly, as the proportion of silica in the sintering ink increases, the difficulty of post-sintering washing increases, and the washing time needs to be extended.

[0271] Reference Standards:

[0272] 1. GB / T15763.2-2009, which specifies the production and application of homogeneous tempered glass.

[0273] 2. GB / T 30020-2023, the standard for glass defect detection.

[0274] 3. GB / T 2410-2008, the transmittance test standard.

[0275] It should be noted that the above embodiments are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. For those of ordinary skill in the art, other different forms of changes or modifications can be made based on the above description. It is impossible to list all the embodiments here. Any obvious changes or modifications derived from the technical solution of the present invention still fall within the protection scope of the present invention.

Claims

1. A heat bending protection ink, characterized in that: In parts by weight, it comprises: 23-55 parts of solvent, 3-12 parts of water-based dispersion resin, 25-55 parts of glass powder, and 2-10 parts of pigment; The glass powder comprises, by weight: 5-15 parts of SiO2, 60-90 parts of Bi2O3, 5-10 parts of B2O3, 8-15 parts of ZnO, 0.5-5 parts of lithium carbonate, 0.2-2.0 parts of sodium carbonate, and 0.2-2 parts of potassium carbonate.

2. The heat bending protection ink according to claim 1, characterized in that: The solvent comprises 3-15 parts of auxiliary solvent and 20-40 parts of main solvent, wherein the auxiliary solvent comprises one or more of methanol, ethanol, propanol, ethylene glycol, glycerol, propylene glycol methyl ether and ethylene glycol methyl ether; and the main solvent is water.

3. The heat bending protection ink according to claim 1, characterized in that: The water-based dispersed resin includes one or more of water-based polyurethane, water-based acrylic resin, water-based phenolic resin, water-based rosin resin, and styrene-maleic anhydride-ammonia hydrated resin.

4. The heat bending protection ink according to claim 1, characterized in that: The pigment includes one or more of iron oxide black, cobalt black, copper chrome black, and copper manganese black.

5. The heat bending protection ink according to claim 1, characterized in that: The particle size of the heat bending protection ink is 200-800nm.

6. The heat bending protection ink according to any one of claims 1 to 5, characterized in that: The method for preparing the glass powder comprises the following steps: After the components of the glass powder are evenly mixed, they are subjected to high-temperature melting, rapid cooling, drying and grinding to obtain glass powder; preferably, the high-temperature melting process is: controlling the heating rate at 1-2°C / min, and keeping the temperature at 800-900°C for 30-50min, and then heating the temperature at a heating rate of 1-2°C / min to 1200-1300°C, and keeping the temperature for 2-3h.

7. A heat-bending protective layer, characterized in that: The invention comprises an ink layer, wherein the ink layer is obtained by printing the heat bending protection ink according to any one of claims 1 to 6 on the glass surface by inkjet printing and then drying at 120-150° C. for 30-60 seconds.

8. The heat-bending protective layer according to claim 7, characterized in that: The thickness of the ink layer is 1-2 μm.

9. The heat-bending protective layer according to claim 7, characterized in that: The heat bending protection layer further comprises an anti-sticking layer, and the anti-sticking layer is arranged on the surface of the ink layer; preferably, the dry film thickness of the anti-sticking layer is 50-200nm.

10. The heat-bending protective layer according to claim 9, characterized in that: The anti-sticking layer is obtained by drying the anti-sticking ink at 120-150° C. for 30-60 seconds; preferably, the anti-sticking ink comprises, by weight: 60-90 parts of neutral silica sol, 5-15 parts of water-soluble PVA resin and 5-30 parts of deionized water.

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