阅读说明：本技术 一种手机3d后盖保护材料及其制备方法 (Mobile phone 3D rear cover protection material and preparation method thereof ) 是由 张福军 周卫卫 于 2020-03-26 设计创作，主要内容包括：一种手机3D后盖保护材料,按重量百分比其组分为5-10％MgAl<Sub>2</Sub>O<Sub>4</Sub>,25-30％MgO·Al<Sub>2</Sub>O<Sub>3</Sub>·SiO<Sub>2</Sub>,7-9％SiO<Sub>2</Sub>·MgO·B<Sub>2</Sub>O<Sub>3</Sub>,7-9％SnO·P<Sub>2</Sub>O<Sub>5</Sub>,6-8％SiO<Sub>2</Sub>·B<Sub>2</Sub>O<Sub>3</Sub>·ZnO,19-22％SiO<Sub>2</Sub>·R<Sub>2</Sub>O·TiO<Sub>2</Sub>,2-3％2Li<Sub>2</Sub>O·SiO<Sub>2</Sub>,14-16％Na<Sub>2</Sub>O·2SiO<Sub>2</Sub>,3-6％Cr<Sub>2</Sub>O<Sub>3</Sub>；采用低温热压烧结,引入大量的陶瓷晶体,阻挡摔落时微裂纹的扩展,低温烧结体中引入碱金属离子,进行化学强化,结合高强玻璃本体,进一步增加材料的抗摔性能；同时引入的染色成分可使之成为颜色漂亮的成品,抵消烧结体不透明的缺陷。(A3D rear cover protection material for a mobile phone comprises 5-10 wt% of MgAl 2 O 4 ，25‑30％MgO·Al 2 O 3 ·SiO 2 ，7‑9％SiO 2 ·MgO·B 2 O 3 ，7‑9％SnO·P 2 O 5 ，6‑8％SiO 2 ·B 2 O 3 ·ZnO，19‑22％SiO 2 ·R 2 O·TiO 2 ，2‑3％2Li 2 O·SiO 2 ，14‑16％Na 2 O·2SiO 2 ，3‑6％Cr 2 O 3 (ii) a The low-temperature hot-pressing sintering is adopted, a large amount of ceramic crystals are introduced to block the expansion of microcracks during falling, alkali metal ions are introduced into a low-temperature sintered body to carry out chemical strengthening, and the anti-falling performance of the material is further improved by combining a high-strength glass body; meanwhile, the introduced dyeing component can make the sintered body become a finished product with beautiful color, and the defect of opaqueness of the sintered body is counteracted.)

1. The utility model provides a lid protection material behind 3D cell-phone which characterized in that: comprises the following components in percentage by mass: 5-10% of MgAl₂O₄，25-30％MgO·Al₂O₃·SiO₂，7-9％SiO₂·MgO·B₂O₃，7-9％SnO·P₂O₅，6-8％SiO₂·B₂O₃·ZnO，19-22％SiO₂·R₂O·TiO₂，2-3％2Li₂O·SiO₂，14-16％Na₂O·2SiO₂，3-6％Cr₂O₃。

2. The 3D mobile phone rear cover protection material according to claim 1, wherein MgAl is₂O₄The mass percentage of the components is 8-10%; the particle size distribution is 0.5um <D50＜1um,D98＜3um。

3. The 3D handset back cover protection material according to claim 1 or 2, wherein MgO-Al is used₂O₃-SiO₂The mass percentage of the components is 27-30%; the particle size distribution is 2um < D50 < 3um, D98 < 5 um.

4. The 3D mobile phone rear cover protection material according to claim 1 or 2, wherein MgO-Al₂O₃-SiO₂SiO with the specific mass percent of 65%₂25% of Al₂O₃10% of MgO.

5. The material for protecting the rear cover of a 3D mobile phone according to claim 1 or 2, wherein SiO is₂·MgO·B₂O₃The particle size distribution is 2um < D50 < 3um, D98 < 3 um.

6. The 3D mobile phone rear cover protection material according to claim 1 or 2, characterized in that SnO & P₂O₅The particle size distribution is 2um < D50 < 3um, D98 < 5 um.

7. The material for protecting the rear cover of a 3D mobile phone according to claim 1 or 2, wherein SiO is₂·B₂O₃The grain size distribution of ZnO is 2um < D50 < 3um, D98 < 5 um.

8. The material for protecting the rear cover of a 3D mobile phone according to claim 1 or 2, wherein SiO is₂·R₂O·TiO₂The particle size distribution is 1um < D50 < 2um, D98 < 4 um.

9. The material for protecting the rear cover of a 3D mobile phone according to claim 1 or 2, wherein SiO is₂·R₂O·TiO₂Characterized by being SiO₂·R₂O·TiO₂Is SiO₂·Li₂O·TiO₂、SiO₂·Na₂O·TiO₂、SiO₂·K₂O·TiO₂One or more of;

when the number of the components is more than one, the mass percentage of the components satisfies SiO₂·Li₂O·TiO₂+SiO₂·K₂O·TiO₂≤SiO₂·Na₂O·TiO₂。

10. The 3D phone rear cover protection material according to claim 9, wherein the mass percent 2Li₂O·SiO₂：Na₂O·2SiO₂﹤1:5。

11. The 3D mobile phone rear cover protection material according to claim 9, wherein the Cr is₂O₃The particle size distribution is 1.5um < D50 < 2.5um, D98 < 4.5 um.

12. A preparation method of a mobile phone 3D rear cover protection material comprises the following steps:

s1, weighing the raw materials of claims 1-13, mixing the raw materials with water according to the proportion of 100: 10-100: 20, and premixing and stirring the mixture by a stirrer to form slurry;

s2, grinding the premixed slurry by using a grinder;

s3, mixing and stirring the ground slurry by a stirrer;

s4, adding the slurry into a die for pressing, demolding and drying in a mesh belt furnace;

s5, sintering the dried slurry by a graphite mould in a hot pressing manner;

s6, carrying out chemical strengthening on the hot-pressed and sintered material, wherein the specific chemical strengthening process comprises the following steps: carrying out ion exchange treatment in potassium nitrate molten salt at the temperature of 420-440 ℃ for 2-5h to obtain the 3D mobile phone rear cover protective material;

and step S1, the premixing and stirring of the stirrer is gradient stirring, the gradient stirring procedure comprises the steps of sequentially adopting, stirring at the rotating speed of 8-12rpm for 25-35min in the first stage, stirring at the rotating speed of 23-27rpm for 50-70min in the second stage, stirring at the rotating speed of 43-47rpm for 30-40min in the third stage, stirring at the rotating speed of 53-57rpm for 20-30min in the fourth stage, and adopting at least three gradient stirring stages in the four gradient stirring stages.

13. The method for preparing a 3D rear cover protective material for a mobile phone according to claim 12, wherein the gradient stirring procedure comprises sequentially performing a first stage of stirring at a rotation speed of 10rpm for 25-35min, a second stage of stirring at a rotation speed of 25rpm for 50-70min, a third stage of stirring at a rotation speed of 45rpm for 30-40min, a fourth stage of stirring at a rotation speed of 55rpm for 20-30min, and at least three gradient stirring stages are performed in the four gradient stirring stages;

step S2, the grinding machine grinds in a gradient mode, the gradient grinding adopts a gap mode, the grinding program sequentially adopts, the first grinding gap is 20-30um, the pressure of the discharging blade is 7-8bar, the rotating speed of the discharging roller is 50-100rpm, the second grinding gap is 18-26um, the pressure of the discharging blade is 7-8bar, the rotating speed of the discharging roller is 50-100rpm, the third grinding gap is 14-17um, the pressure of the discharging blade is 9-10bar, the rotating speed of the discharging roller is 50-100rpm, the fourth grinding gap is 8-12um, the pressure of the discharging blade is 9-10bar, the rotating speed of the discharging roller is 150-200rpm, the fifth grinding gap is 8-12um, the pressure of the discharging blade is 11-12bar, the rotating speed of the discharging roller is 150-200rpm, and the sixth grinding gap is 4-6um, the pressure of a discharging blade is 11-12bar, the rotating speed of a discharging roller is 150-200rpm, the grinding gap for the seventh time is 4-6um, the pressure of the discharging blade is 11-12bar, the rotating speed of the discharging roller is 300-400rpm, the grinding gap for the eighth time is 4-6um, the pressure of the discharging blade is 11-12bar, the rotating speed of the discharging roller is 450-550rpm, and at least five grinding programs are adopted in the eight gradient grinding.

14. The method of claim 12, wherein the grinding process comprises grinding the cell phone 3D rear cover with a gap of 25um for the first time, a blade pressure of 7-8bar for the discharge, a rotation speed of 50-100rpm for the discharge roller, a gap of 20um for the second time, a pressure of 7-8bar for the discharge roller, a rotation speed of 50-100rpm for the discharge roller, a rotation speed of 15um for the third time, a pressure of 9-10bar for the discharge blade, a rotation speed of 50-100rpm for the discharge roller, a rotation speed of 10um for the fourth time, a pressure of 9-10bar for the discharge blade, a rotation speed of 150-200rpm for the discharge roller, a rotation speed of 10um for the fifth time, a pressure of 11-12bar for the discharge roller, a rotation speed of 150-200rpm for the discharge roller, a gap of 5um for the sixth time, a pressure of 11-12bar for the discharge blade, the rotating speed of a discharging roller is 150-200rpm, the grinding gap of the seventh time is 5um, the pressure of a discharging blade is 11-12bar, the rotating speed of the discharging roller is 300-400rpm, the grinding gap of the eighth time is 5um, the pressure of the discharging blade is 11-12bar, the rotating speed of the discharging roller is 450-550rpm, and at least five grinding programs are adopted in the eight gradient grinding;

and step S3, the mixing and stirring of the double-planetary stirrer is gradient stirring, the gradient stirring procedure comprises the steps of stirring for 10-15min at the rotating speed of 10-20rpm in the first stage, stirring for 25-30min at the rotating speed of 20-30rpm in the second stage, stirring for 25-30min at the rotating speed of 35-45rpm in the third stage, and at least one of the three gradient stirring steps is adopted.

15. The method for preparing a 3D rear cover protective material for a mobile phone according to claim 12, wherein the gradient stirring procedure comprises sequentially performing a first stage of stirring at 15rpm for 10-15min, a second stage of stirring at 25rpm for 25-30min, a third stage of stirring at 40rpm for 25-30min, wherein at least one of the three gradient stirring stages is performed;

step S4, the mesh belt furnace drying is gradient drying, the gradient drying procedure mainly comprises two stages, the first stage is 20-80 ℃, 4-7 sections of temperature zones are set, one temperature zone is set at intervals of 10-20 ℃ from 20 ℃ to 90 ℃, the residence time of each temperature zone is 2-5min, the second stage is 3-5 sections of temperature zones, one temperature zone is set at intervals of 5-10 ℃ from 90 ℃ to 110 ℃, and the residence time of each temperature zone is 10-50 min;

s5, the graphite mold hot-pressing sintering is gradient hot-pressing sintering, the gradient procedure mainly comprises the steps of sequentially adopting a first stage, heating the graphite mold at a hot-pressing temperature of 20 ℃, a pressure of 1-5MPa and keeping the temperature for 10min, a second stage, heating the graphite mold from 20 ℃ to 400 ℃, a heating rate of 5-10 ℃/min and a pressure of 0-2MPa, a third stage, heating the graphite mold from 400 ℃, a heating rate of 2-5 ℃/min and heating the graphite mold to 520-580 ℃, a pressure of 0-5MPa, a fourth stage, keeping the temperature constant, keeping the pressure of 8-10MPa for 10-15min, a fifth stage, keeping the temperature constant, keeping the pressure of 15-20MPa for 20-30min, a sixth stage, cooling the graphite mold to 400 ℃, a cooling rate of 2-5 ℃/min and keeping the pressure constant, a seventh stage, cooling the graphite mold from 400 ℃ to 20 ℃, a cooling rate of 10-20 ℃/min, the pressure is 0-5Mpa, and at least five stages of procedures are adopted in the seven gradient hot pressing.

16. The method for preparing a 3D rear cover protection material for a mobile phone according to claim 12, wherein the gradient hot pressing sintering comprises a first stage of heating to 400 ℃ from 20 ℃ to 5Mpa at a hot pressing temperature of 20 ℃ for 10min, a second stage of heating to 5 ℃ to 10 ℃/min at a heating rate of 5-10 ℃/min at a pressure of 0Mpa, a third stage of heating to 400 ℃ at a heating rate of 2-5 ℃/min to 520-580 ℃ at a pressure of 5Mpa, a fourth stage of maintaining the temperature constant at a pressure of 8-10Mpa for 10-15min, a fifth stage of maintaining the temperature constant at a pressure of 15-20Mpa for 20-30min, a sixth stage of cooling to 400 ℃ at a cooling rate of 2-5 ℃/min at a pressure of 8-10Mpa, a seventh stage of cooling to 20 ℃ from 400 ℃, the cooling rate is 10-20 ℃/min, the pressure is 0Mpa, and at least five stages of procedures are adopted in the seven gradient hot pressing.

Technical Field

The application belongs to the field of mobile phone cover materials, and particularly relates to a mobile phone 3D rear cover protection material and a preparation field thereof.

Background

The mobile phone rear cover plate adopts a 3D structure, so that the holding feeling of a mobile phone of a consumer can be improved, and the mobile phone rear cover plate becomes a standard matching option of a flagship type at present. With the increased pace of commercialization of 5G, the demand for 3D back cover materials for 5G cellular phones continues to increase.

The original material for the 3D mobile phone rear cover mainly comprises 4 types of metal, glass, ceramic, special plastic and the like, but the metal rear cover material can generate obvious absorption and shielding effects on 5G high-frequency signals, so that mobile phone signals are weakened, and therefore the metal material cannot be applied to the rear cover plate of the 5G mobile phone.

Among three materials of the existing glass, ceramic and special plastic, plastic is easy for 3D-shaped injection molding processing, but is low in hardness, easy to scratch and easy to harden, and affects the experience of consumers, so that a small amount of low-end non-smart phones can be selected and adopted. Although the ceramic material is used as the rear cover plate, the hardness is high, the ceramic material is not easy to scratch, and the inherent artistic aesthetic feeling of the ceramic can improve the user experience of consumers, the ceramic material is not easy to process into a 3D shape due to the inherent ceramic crystal structure, in addition, only a small number of flagship models are selectively used due to the high production cost of the ceramic cover plate at the present stage, and the ceramic material is easy to fragment when the impact force is trapped, so that the falling resistance is poor.

The most practical applications of the protective materials for the 5G mobile phone rear cover plate on the market are mainly glass materials. The glass material is lower on the one hand, and is less to 5G communication frequency's absorption and shielding influence, can satisfy the requirement, and on the other hand, glass texture itself can satisfy consumer's user experience. However, when the glass material is made into a 3D shape, the softening point is higher when the anti-falling performance is ensured due to the existing glass material, the 3D hot press forming temperature is close to the use limit of a graphite mold, the yield of the hot press process is lower, and the inner surface and the outer surface of the bent part are not shrunk uniformly after hot pressing, so that the processing is difficult. Although attempts have been made to lower the softening point by increasing the alkali metal content in the glass formulation, etc., the glass skeleton structure is further destroyed after the alkali metal content is increased, resulting in unsatisfactory falling resistance.

Disclosure of Invention

In order to solve the problem of difficulty in 3D hot press molding of the anti-falling material, the invention provides a 3D mobile phone rear cover protection material and a preparation method thereof, wherein the preparation method comprises the following steps:

the utility model provides a lid protection material behind 3D cell-phone which characterized in that: comprises the following components in percentage by mass: consists of MgAl 5-10 wt%₂O₄，25-30％MgO·Al₂O₃·SiO₂，7-9％SiO₂·MgO·B₂O₃，7-9％SnO·P₂O₅，6-8％SiO₂·B₂O₃·ZnO，19-22％SiO₂·R₂O·TiO₂，2-3％2Li₂O·SiO₂，14-16％Na₂O·2SiO₂，3-6％Cr₂O₃。

Preferably: the MgAl₂O₄The mass percentage of the components is 8-10%.

Preferably: the MgAl₂O₄The particle size distribution is that D50 is more than 0.5um and less than 1um, and D98 is less than 3 um.

Preferably: the MgO-Al₂O₃-SiO₂The mass percentage of the components is 27-30%.

Preferably: the MgO-Al₂O₃-SiO₂The particle size distribution is 2um < D50 < 3um, D98 < 5 um.

Preferably: the MgO-Al₂O₃-SiO₂SiO with the specific mass percent of 65%₂25% of Al₂O₃10% of MgO.

Preferably: the SiO₂·MgO·B₂O₃The particle size distribution is 2um < D50 < 3um, D98 < 3 um.

Preferably: the SnO. P₂O₅The particle size distribution is 2um < D50 < 3um, D98 < 5 um.

Preferably: the SiO₂·B₂O₃The grain size distribution of ZnO is 2um < D50 < 3um, D98 < 5 um.

Preferably: the SiO₂·R₂O·TiO₂The particle size distribution is 1um < D50 < 2um, D98 < 4 um.

Preferably: the SiO₂·R₂O·TiO₂Is SiO₂·Li₂O·TiO₂、SiO₂·Na₂O·TiO₂、SiO₂·K₂O·TiO₂At least one of (1).

Preferably: the SiO₂·R₂O·TiO₂In the component mass percent of SiO₂·Li₂O·TiO₂+SiO₂·K₂O·TiO₂≤SiO₂·Na₂O·TiO₂。

Preferably: the 2Li₂O·SiO₂The mass percent of the components is equal to Na₂O·2SiO₂The mass percentage of the components satisfies the ratio of less than 1: 5.

Preferably: the Cr is₂O₃The particle size distribution is 1.5um < D50 < 2.5um, D98 < 4.5 um.

A preparation method of a mobile phone 3D rear cover protection material comprises the following steps:

s1, weighing the raw materials, mixing the raw materials with water according to the proportion of 100: 10-100: 20, and premixing and stirring the raw materials by using a double-planet stirrer to form slurry.

S2 the premixed slurry is ground with a three-roll mill.

S3, the ground slurry is mixed and stirred by a double-planet stirrer.

S4, adding the slurry into a die for pressing, demoulding and drying in a mesh belt furnace.

And S5, hot-pressing and sintering the dried slurry by using a graphite mold.

S6, carrying out chemical strengthening on the hot-pressed and sintered material, wherein the specific chemical strengthening process comprises the following steps: and carrying out ion exchange treatment in potassium nitrate molten salt at the temperature of 420-440 ℃ for 2-5h to obtain the 3D mobile phone rear cover protective material.

And step S1, the premixing and stirring of the double planetary stirrer is gradient stirring, the gradient stirring procedure comprises the steps of stirring for 25-35min at the rotating speed of 8-12rpm in the first stage, stirring for 50-70min at the rotating speed of 23-27rpm in the second stage, stirring for 30-40min at the rotating speed of 43-47rpm in the third stage, and stirring for 20-30min at the rotating speed of 53-57rpm in the fourth stage, wherein at least three gradient stirring stages are adopted in the gradient.

The further procedure of the gradient stirring comprises the steps of sequentially adopting a first stage of stirring at the rotating speed of 10rpm for 25-35min, a second stage of stirring at the rotating speed of 25rpm for 50-70min, a third stage of stirring at the rotating speed of 45rpm for 30-40min, and a fourth stage of stirring at the rotating speed of 55rpm for 20-30min, wherein at least three stages of gradient stirring are adopted in the above gradient.

Step S2, the three-roll grinder grinds to be a gradient grinder, the gradient grinder adopts a three-roll gap mode, the grinding program is adopted in sequence, the first grinding gap is 20-30um, the pressure of a discharging blade is 7-8bar, the rotating speed of the discharging roller is 50-100rpm, the second grinding gap is 18-26um, the pressure of the discharging blade is 7-8bar, the rotating speed of the discharging roller is 50-100rpm, the third grinding gap is 14-17um, the pressure of the discharging blade is 9-10bar, the rotating speed of the discharging roller is 50-100rpm, the fourth grinding gap is 8-12um, the pressure of the discharging blade is 9-10bar, the rotating speed of the discharging roller is 150-200rpm, the fifth grinding gap is 8-12um, the pressure of the discharging blade is 11-12bar, the rotating speed of the discharging roller is 150-200rpm, and the sixth grinding gap is 4-6um, the pressure of a discharging blade is 11-12bar, the rotating speed of a discharging roller is 150-200rpm, the grinding gap for the seventh time is 4-6um, the pressure of the discharging blade is 11-12bar, the rotating speed of the discharging roller is 300-400rpm, the grinding gap for the eighth time is 4-6um, the pressure of the discharging blade is 11-12bar, the rotating speed of the discharging roller is 450-550rpm, and at least five grinding programs are selected from the gradients.

Further, the grinding procedure is adopted in sequence, the first grinding gap is 25um, the pressure of the discharging blade is 7-8bar, the rotating speed of the discharging roller is 50-100rpm, the second grinding gap is 20um, the pressure of the discharging blade is 7-8bar, the rotating speed of the discharging roller is 50-100rpm, the third grinding gap is 15um, the pressure of the discharging blade is 9-10bar, the rotating speed of the discharging roller is 50-100rpm, the fourth grinding gap is 10um, the pressure of the discharging blade is 9-10bar, the rotating speed of the discharging roller is 150-200rpm, the fifth grinding gap is 10um, the pressure of the discharging blade is 11-12, the rotating speed of the discharging roller is 150-200rpm, the sixth grinding gap is 5um, the pressure of the discharging blade is 11-12bar, the rotating speed of the discharging roller is 150-200rpm, the seventh grinding gap is 5um, and the pressure of the discharging blade is 11-12bar, the rotating speed of the discharging roller is 300-400rpm, the grinding gap of the eighth grinding is 5um, the pressure of the discharging blade is 11-12bar, the rotating speed of the discharging roller is 450-550rpm, and at least five grinding procedures are performed in the gradient.

And step S3, the mixing and stirring of the double-planetary stirrer is gradient stirring, the gradient stirring procedure comprises the steps of stirring for 10-15min at the rotating speed of 10-20rpm in the first stage, stirring for 25-30min at the rotating speed of 20-30rpm in the second stage, and stirring for 25-30min at the rotating speed of 35-45rpm in the third stage, wherein at least one stage in the gradient is adopted.

Further, the procedure of the gradient stirring comprises the steps of sequentially adopting a first stage of stirring at a rotating speed of 15rpm for 10-15min, a second stage of stirring at a rotating speed of 25rpm for 25-30min, and a third stage of stirring at a rotating speed of 40rpm for 25-30min, wherein at least one stage is selected from the gradients.

Step S4, the mesh belt oven drying is gradient drying, the gradient drying procedure mainly comprises two stages, the first stage is 20-80 ℃, 4-7 sections of temperature zones are set, one temperature zone is set at intervals of 10-20 ℃ from 20 ℃ to 90 ℃, the residence time of each temperature zone is 2-5min, the second stage is 3-5 sections of temperature zones, one temperature zone is set at intervals of 5-10 ℃ from 90 ℃ to 110 ℃, and the residence time of each temperature zone is 10-50 min.

S5, the graphite mold hot-pressing sintering is gradient hot-pressing sintering, the gradient procedure mainly comprises the steps of sequentially adopting a first stage, heating the graphite mold at a hot-pressing temperature of 20 ℃, a pressure of 1-5MPa and keeping the temperature for 10min, a second stage, heating the graphite mold from 20 ℃ to 400 ℃, a heating rate of 5-10 ℃/min and a pressure of 0-2MPa, a third stage, heating the graphite mold from 400 ℃, a heating rate of 2-5 ℃/min and heating the graphite mold to 520-580 ℃, a pressure of 0-5MPa, a fourth stage, keeping the temperature constant, keeping the pressure of 8-10MPa for 10-15min, a fifth stage, keeping the temperature constant, keeping the pressure of 15-20MPa for 20-30min, a sixth stage, cooling the graphite mold to 400 ℃, a cooling rate of 2-5 ℃/min and keeping the pressure constant, a seventh stage, cooling the graphite mold from 400 ℃ to 20 ℃, a cooling rate of 10-20 ℃/min, pressure 0-5MPa, and at least five steps in the gradient.

Further, the gradient hot-pressing sintering comprises a first stage, wherein the hot-pressing temperature is 20 ℃, the pressure is 5Mpa, the temperature is kept for 10min, a second stage, the temperature is increased from 20 ℃ to 400 ℃, the temperature increasing rate is 5-10 ℃/min, the pressure is 0Mpa, a third stage, the temperature is increased from 400 ℃, the temperature increasing rate is 2-5 ℃/min, the temperature is increased to 520-580 ℃, the pressure is 5Mpa, the temperature is kept unchanged, the pressure is 8-10Mpa, the temperature is kept for 10-15min, a fifth stage, the temperature is kept unchanged, the pressure is 15-20Mpa, the temperature is reduced to 400 ℃, the temperature reducing rate is 2-5 ℃/min, the pressure is kept unchanged, and a seventh stage, the temperature is reduced from 400 ℃ to 20 ℃, the temperature reducing rate is 10-20 ℃/min, the pressure is 0Mpa, and at least five stages of the gradient are sequentially adopted.

The technical principle of the invention is as follows: the low-temperature sintering agent is used for bonding the high-strength glass and the ceramic crystal to realize the one-step forming of 3D hot-pressing sintering

The beneficial technical effects of the invention are as follows: according to the glass ceramic sintered body, a large number of ceramic crystals are introduced to block the expansion of microcracks during falling, alkali metal ions are introduced into the low-temperature sintered body to perform chemical strengthening, and the high-strength glass body is combined to further increase the falling resistance of the material. Meanwhile, the introduced dyeing component can make the sintered body become a finished product with beautiful color, and the defect of opaqueness of the sintered body is counteracted.

Detailed Description

In order to clearly understand the technical spirit and the advantages of the present invention, the following detailed description is given by way of examples, but the description of the examples is not intended to limit the scope of the present invention, and any equivalent changes made according to the present inventive concept, which are merely in form and not in substance, should be considered as the scope of the present invention.

The invention discloses a 3D mobile phone rear cover protection material which is characterized in that: comprises the following components in percentage by weight: consists of MgAl 5-10 wt%₂O₄，25-30％MgO·Al₂O₃·SiO₂，7-9％SiO₂·MgO·B₂O₃，7-9％SnO·P₂O₅，6-8％SiO₂·B₂O₃·ZnO，19-22％SiO₂·R₂O·TiO₂，2-3％2Li₂O·SiO₂，14-16％Na₂O·2SiO₂，3-6％Cr₂O₃。

The principle of the present invention that the 3D rear cover protective material for a mobile phone limits its components and contents is explained as follows.

MgAl₂O₄In the magnesium aluminate spinel, oxygen atoms are equivalent and are arranged in cubic packing in the magnesium aluminate spinel, and because the oxygen atoms are much larger than magnesium and aluminum ions, metal ions of aluminum and magnesium metal are respectively inserted into octahedral and tetrahedral gaps formed by the oxygen atoms according to packing density according to a certain rule and keep electric neutrality. MgAl₂O₄High temperature resistance, corrosion resistance, abrasion resistance, high impact resistance, high hardness and good strength. In the formula system, MgAl₂O₄The introduction of the formula mainly uses the high-hardness high-impact-resistance high-.

MgO·Al₂O₃·SiO₂Has similar performance to that of magnesium-aluminum-silicon high-strength glass fiber, especially has higher elastic modulus, higher strength and better impact resistance, and MgO-Al in the formula system₂O₃·SiO₂The introduction of the compound mainly uses the compound to improve the anti-falling performance, the compound is used as a basic component, the content of the component is 25-35%, and when the content is less than 25%, MgO & Al₂O₃·SiO₂The effective base structure after sintering can not be formed, or the structure is incomplete, so that the shock resistance of the sintered body is reduced, and when the content is more than 30 percent, excessive MgO. Al₂O₃·SiO₂Can block the subsequent chemical strengthening channel, influence the uniformity and the depth of chemical strengthening and reduce the anti-falling performance.

SiO₂·MgO·B₂O₃、SnO·P₂O₅、SiO₂·B₂O₃·ZnO、SiO₂·R₂O·TiO₂All are sintering aids, the sintering temperature and time can be effectively controlled by adjusting the proportion and the particle size distribution, and SiO₂·R₂O·TiO₂The introduction of Li, Na and K provides a part of ions for exchange for subsequent chemical strengthening, and the content satisfies SiO₂·Li₂O·TiO₂+SiO₂·K₂O·TiO₂≤SiO₂·Na₂The O & TiO2 is beneficial to controlling the concentration difference between K ions in the molten salt and K ions in the glass and the concentration difference between Na ions in the molten salt and Na ions in the glass to be large enough during K, Na ion exchange, thereby ensuring that the ion exchange can be controlled sufficiently.

2Li₂O·SiO₂，Na₂O·2SiO₂The three-roller grinding dispersion device is mainly used for reacting with added water when slurry is prepared to form jelly, is used for adjusting the overall viscosity of the slurry, and is convenient for better realizing three-roller grinding dispersion and pressing of a 3D shape. Meanwhile, the introduced Li and Na ions are the ion concentration difference required by chemically enhanced ion exchange, so that sufficient exchange is ensured.

Cr₂O₃The main purpose is to form beautiful green color of the sinter and to fill part of the gaps. In addition, Cr₂O₃The acid and alkali resistance is good, and the acid and alkali resistance can be further enhanced besides forming green by adding a proper amount.

Embodiments 1-8 (table 1) of the present invention relate to a mobile phone 3D rear cover protection material and a preparation method thereof, wherein the material comprises the following components by weight: 5-10% of MgAl₂O₄，25-30％MgO·Al₂O₃·SiO₂，7-9％SiO₂·MgO·B₂O₃，7-9％SnO·P₂O₅，6-8％SiO₂·B₂O₃·ZnO，19-22％SiO₂·R₂O·TiO₂，2-3％2Li₂O·SiO₂，14-16％Na₂O·2SiO₂，4-6％Cr₂O₃。