CN112979161A - Preparation method and application of tungsten phosphate glass based on photochromic effect - Google Patents
Preparation method and application of tungsten phosphate glass based on photochromic effect Download PDFInfo
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- CN112979161A CN112979161A CN202110262163.7A CN202110262163A CN112979161A CN 112979161 A CN112979161 A CN 112979161A CN 202110262163 A CN202110262163 A CN 202110262163A CN 112979161 A CN112979161 A CN 112979161A
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- phosphate glass
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- ABKDZANKXKCXKG-UHFFFAOYSA-B P(=O)([O-])([O-])[O-].[W+4].P(=O)([O-])([O-])[O-].P(=O)([O-])([O-])[O-].P(=O)([O-])([O-])[O-].[W+4].[W+4] Chemical compound P(=O)([O-])([O-])[O-].[W+4].P(=O)([O-])([O-])[O-].P(=O)([O-])([O-])[O-].P(=O)([O-])([O-])[O-].[W+4].[W+4] ABKDZANKXKCXKG-UHFFFAOYSA-B 0.000 title claims abstract description 56
- 239000005365 phosphate glass Substances 0.000 title claims abstract description 56
- 230000000694 effects Effects 0.000 title claims abstract description 30
- 238000002360 preparation method Methods 0.000 title claims abstract description 11
- 238000000034 method Methods 0.000 claims abstract description 19
- 238000002844 melting Methods 0.000 claims abstract description 11
- 230000008018 melting Effects 0.000 claims abstract description 11
- 239000000463 material Substances 0.000 claims abstract description 9
- 229910001369 Brass Inorganic materials 0.000 claims abstract description 6
- 238000000137 annealing Methods 0.000 claims abstract description 6
- 239000010951 brass Substances 0.000 claims abstract description 6
- 238000010791 quenching Methods 0.000 claims abstract description 6
- 230000000171 quenching effect Effects 0.000 claims abstract description 6
- ADCOVFLJGNWWNZ-UHFFFAOYSA-N antimony trioxide Inorganic materials O=[Sb]O[Sb]=O ADCOVFLJGNWWNZ-UHFFFAOYSA-N 0.000 claims description 11
- 229910001632 barium fluoride Inorganic materials 0.000 claims description 11
- 239000002994 raw material Substances 0.000 claims description 11
- 229910000029 sodium carbonate Inorganic materials 0.000 claims description 11
- CDBYLPFSWZWCQE-UHFFFAOYSA-L sodium carbonate Substances [Na+].[Na+].[O-]C([O-])=O CDBYLPFSWZWCQE-UHFFFAOYSA-L 0.000 claims description 11
- 229910000162 sodium phosphate Inorganic materials 0.000 claims description 11
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims description 5
- 238000001816 cooling Methods 0.000 claims description 5
- 238000002156 mixing Methods 0.000 claims description 5
- 239000000203 mixture Substances 0.000 claims description 5
- 239000004570 mortar (masonry) Substances 0.000 claims description 5
- 238000005303 weighing Methods 0.000 claims description 5
- 239000011521 glass Substances 0.000 abstract description 12
- 210000004243 sweat Anatomy 0.000 abstract description 8
- 238000004321 preservation Methods 0.000 abstract description 3
- 239000004519 grease Substances 0.000 abstract 1
- 238000005286 illumination Methods 0.000 abstract 1
- PBYZMCDFOULPGH-UHFFFAOYSA-N tungstate Chemical compound [O-][W]([O-])(=O)=O PBYZMCDFOULPGH-UHFFFAOYSA-N 0.000 abstract 1
- 230000035882 stress Effects 0.000 description 8
- 230000003287 optical effect Effects 0.000 description 5
- 238000005245 sintering Methods 0.000 description 4
- 230000007547 defect Effects 0.000 description 3
- 238000003825 pressing Methods 0.000 description 3
- 238000003860 storage Methods 0.000 description 2
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 1
- 230000032683 aging Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000012790 confirmation Methods 0.000 description 1
- 239000003814 drug Substances 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 210000002615 epidermis Anatomy 0.000 description 1
- 238000011842 forensic investigation Methods 0.000 description 1
- 238000003384 imaging method Methods 0.000 description 1
- 238000009776 industrial production Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 229910052710 silicon Inorganic materials 0.000 description 1
- 239000010703 silicon Substances 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03C—CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
- C03C4/00—Compositions for glass with special properties
- C03C4/04—Compositions for glass with special properties for photosensitive glass
- C03C4/06—Compositions for glass with special properties for photosensitive glass for phototropic or photochromic glass
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
- C03B19/00—Other methods of shaping glass
- C03B19/02—Other methods of shaping glass by casting molten glass, e.g. injection moulding
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
- C03B25/00—Annealing glass products
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03C—CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
- C03C1/00—Ingredients generally applicable to manufacture of glasses, glazes, or vitreous enamels
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03C—CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
- C03C3/00—Glass compositions
- C03C3/12—Silica-free oxide glass compositions
- C03C3/16—Silica-free oxide glass compositions containing phosphorus
- C03C3/21—Silica-free oxide glass compositions containing phosphorus containing titanium, zirconium, vanadium, tungsten or molybdenum
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- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Organic Chemistry (AREA)
- Life Sciences & Earth Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- General Chemical & Material Sciences (AREA)
- Geochemistry & Mineralogy (AREA)
- Manufacturing & Machinery (AREA)
- Glass Compositions (AREA)
Abstract
The invention relates to a preparation method and application of tungsten phosphate glass based on a photochromic effect, and belongs to the technical field of fingerprint acquisition and identification. The tungsten phosphate glass is prepared by adopting a conventional melting quenching method. The molten tungstate glass was then poured onto a brass mold and cooled to room temperature. Next, annealing was performed at 420 ℃ for 5 hours to remove thermal strain. Tungsten phosphate glass is obtained. The tungsten phosphate glass is a photochromic material, and the color of the glass is changed from yellow to blue after illumination. The photochromic phenomenon of the tungsten phosphate glass is related to sweat and grease, and after a finger presses the surface of the tungsten phosphate glass to leave a sweat latent fingerprint, the sweat latent fingerprint on the surface of the glass is displayed in a blue obvious fingerprint form by laser irradiation, so that fingerprint collection and identification are realized. The fingerprint collection and identification based on the photochromic phenomenon has the advantages of convenience, good stability, long preservation time, high accuracy and the like.
Description
Technical Field
The invention relates to a preparation method and application of tungsten phosphate glass based on a photochromic effect, and belongs to the technical field of fingerprint acquisition and identification.
Background
Since ancient times, the pattern of fingerprint ridges was unique to everyone and unchangeable throughout the life of the person, and thus fingerprints are widely used as direct biometric information for personal identity storage, identification, or confirmation. Today, storing and recognizing fingerprints are still regarded as a powerful tool for forensic investigation, identification document production, and access control and entry and exit control in some special areas/buildings. The epidermis of the human hand and foot has raised ridges. When a finger touches the surface of an object, sweat and oily substances of the finger can form finger lines which can be regarded as potential fingerprints. The fingerprint of each person has uniqueness, heredity and invariance, and identity identification can be quickly and accurately obtained through fingerprint acquisition. At present, the fingerprint acquisition technology is successfully applied to the fields of finance, telecommunication, traffic, education, medicine and the like, and plays a key role in preventing terrorist activities, maintaining national security and social stability, improving working efficiency and the like. At present, the collection of original images of fingerprints generally comprises optical input by direct pressing, and the fingerprint images are obtained by utilizing the reflection of light; in addition, the method comprises the steps of fingerprint acquisition by a capacitive sensor, temperature sensing acquisition, chip input, ultrasonic input, electromagnetic fingerprint acquisition and the like. Optical fingerprint collection devices are the earliest and most popular devices, but are generally severely distorted due to the limitation of the optical path. In addition, the optical fingerprint acquisition device has some defects caused by aging, and the imaging quality is influenced. The silicon chip fingerprint acquisition technology as a second generation fingerprint acquisition technology also has the defects of poor durability, poor environmental adaptability and the like. Therefore, there is a strong need to develop a simple method to acquire and store latent fingerprints quickly and accurately.
Disclosure of Invention
The invention aims to overcome the defects of stability and accuracy of fingerprint acquisition and identification in the prior optical technology, and adopts a tungsten phosphate glass material with photochromic effect to realize fingerprint acquisition and identification, and after a finger presses the surface of the tungsten phosphate glass to leave a sweat latent fingerprint, the sweat latent fingerprint on the surface of the tungsten phosphate glass is displayed in a blue obvious fingerprint form by laser irradiation, so that fingerprint acquisition and identification are carried out. Compared with the prior fingerprint acquisition and identification technology, the fingerprint acquisition and identification based on the photochromic phenomenon has the advantages of convenience, good stability, long storage time, high accuracy and the like. The invention is realized by the following technical scheme.
A preparation method of a tungsten phosphate glass fingerprint acquisition and identification material based on a photochromic effect is characterized by comprising the following specific steps:
the method comprises the following steps: weighing WO349％-51％,NaH2PO438％-42％,BaF27％-10％,Sb2O30％-2％,Na2CO30.5% -2%, uniformly mixing the raw materials in an agate mortar;
step two: melting the mixture for one hour in air at 1050-1100 ℃ by adopting a conventional melting quenching method to prepare the tungsten phosphate glass without eliminating the thermal effect stress;
step three: pouring the molten tungsten phosphate glass without eliminating the thermal effect stress on a brass mould, and cooling to 20-30 ℃;
step four: annealing the tungsten phosphate glass cooled in the third step at 400-420 ℃ for 5 hours to eliminate thermal strain; obtaining tungsten phosphate glass;
further, in the first step, the raw materials are in the following weight ratio: WO351％,NaH2PO442％,BaF210％,Sb2O32％,Na2CO32％；
Further, in the first step, the raw materials are in the following weight ratio: WO349％,NaH2PO438％,BaF27％,Sb2O30％,Na2CO30.5％；
Further, in the first step, the raw materials are in the following weight ratio: WO350％,NaH2PO440％,BaF28％,Sb2O31％,Na2CO31％；
The invention has the beneficial effects that:
(1) after a finger presses the surface of the tungsten phosphate glass to leave a latent sweat fingerprint, the latent sweat fingerprint on the surface of the tungsten phosphate glass is displayed in a blue obvious fingerprint form by laser irradiation;
(2) the tungsten phosphate glass material synthesized by the invention has excellent photochromic property, and has the advantages of convenience, good stability, long preservation time, high accuracy and the like;
(3) the preparation method is simple in preparation process and low in cost, and is expected to realize industrial production.
Drawings
FIG. 1 is a photograph of a tungstophosphate glass obtained in example 1 of the present invention;
FIG. 2 is a photograph of a tungstophosphate glass obtained in example 2 of the present invention;
FIG. 3 is a photograph of a tungstophosphate glass obtained in example 3 of the present invention;
FIG. 4 is a fingerprint image of the surface of a tungsten phosphate glass obtained in example 3 of the present invention after being subjected to fingerprint pressing and light irradiation;
figure 5 is a photograph of a clear fingerprint obtained from example 3 of the present invention taken after being left in the air for one year.
Detailed Description
The invention is further described with reference to the following drawings and detailed description.
Example 1
The sintering temperature of the tungsten phosphate glass with photochromic effect is 1050 ℃.
The preparation method of the tungsten phosphate glass with photochromic effect comprises the following specific steps:
the method comprises the following steps: weighing WO351％,NaH2PO442％,BaF210％,Sb2O32％,Na2CO32 percent; uniformly mixing the raw materials in an agate mortar;
step two: melting the mixture for one hour in air at 1050 ℃ by adopting a conventional melting quenching method to prepare the tungsten phosphate glass without eliminating the thermal effect stress;
step three: pouring the molten tungsten phosphate glass without eliminating the thermal effect stress on a brass mould, and cooling to 25 ℃;
step four: annealing the tungsten phosphate glass cooled in the third step for 5 hours at 420 ℃ to eliminate thermal strain; obtaining tungsten phosphate glass;
a dark blue colored tungsten phosphate glass was obtained by the method steps of example 1 and had poor transparency, as shown in figure 1.
Example 2
The sintering temperature of the tungsten phosphate glass with photochromic effect is 1050 ℃.
The preparation method of the tungsten phosphate glass with photochromic effect comprises the following specific steps:
the method comprises the following steps: weighing WO349％,NaH2PO438％,BaF27％,Sb2O30％,Na2CO30.5 percent; uniformly mixing the raw materials in an agate mortar;
step two: melting the mixture for one hour in air at 1050 ℃ by adopting a conventional melting quenching method to prepare the tungsten phosphate glass without eliminating the thermal effect stress;
step three: pouring the molten tungsten phosphate glass without eliminating the thermal effect stress on a brass mould, and cooling to 25 ℃;
step four: annealing the tungsten phosphate glass cooled in the third step for 5 hours at 420 ℃ to eliminate thermal strain; obtaining tungsten phosphate glass;
a yellowish tungsten phosphate glass having a general degree of transparency, as shown in fig. 2, was prepared by the procedure of example 2.
Example 3
The sintering temperature of the tungsten phosphate glass with photochromic effect is 1050 ℃.
The preparation method of the tungsten phosphate glass with photochromic effect comprises the following specific steps:
the method comprises the following steps: weighing WO350％,NaH2PO440％,BaF28％,Sb2O31％,Na2CO31 percent; uniformly mixing the raw materials in an agate mortar;
step two: melting the mixture for one hour in air at 1050 ℃ by adopting a conventional melting quenching method to prepare the tungsten phosphate glass without eliminating the thermal effect stress;
step three: pouring the molten tungsten phosphate glass without eliminating the thermal effect stress on a brass mould, and cooling to 25 ℃;
step four: annealing the tungsten phosphate glass cooled in the third step for 5 hours at 420 ℃ to eliminate thermal strain; obtaining tungsten phosphate glass;
the procedure of example 3 produced the most transparent tungsten phosphate glass in a pale yellow color, as shown in FIG. 3.
As shown in fig. 1, 2 and 3, the tungstophosphate glass obtained in the embodiments 1, 2 and 3 of the invention is dark blue opaque glass as can be seen from the figure; examples 2 and 3 are light yellow transparent glasses, but the transparency of the light yellow glass obtained in example 2 is general, and the transparency of the light yellow glass obtained in example 3 is the best.
FIG. 4 shows the tungsten phosphate glass obtained in example 3 after being subjected to fingerprint pressing and laser irradiation, which shows obvious fingerprints due to the photochromic effect of the tungsten phosphate glass; as can be seen, the fingerprint collection is very clear on the tungsten phosphate glass;
FIG. 5 is a picture of the obvious fingerprint obtained in example 3 of the present invention after being placed in the air for one year, from which it can be seen that the fingerprint is still clear and recognizable;
according to the tungsten phosphate glass obtained by the invention, all the glasses obtained at the sintering temperature of 1050 ℃ have photochromic effect, and the fingerprint displayed according to the photochromic phenomenon has the advantages of convenience, good stability, long preservation time and high accuracy. The tungsten phosphate glass with photochromic characteristics has wide application prospect in the field of fingerprint identification and collection.
While the present invention has been described in detail with reference to the embodiments shown in the drawings, the present invention is not limited to the embodiments, and various changes can be made without departing from the spirit and scope of the present invention.
Claims (5)
1. The material is characterized in that the fingerprint collection and identification are realized by utilizing the photochromic effect of the tungsten phosphate glass.
2. The preparation method of the tungsten phosphate glass fingerprint acquisition and identification material based on the photochromic effect according to claim 1, which is characterized by comprising the following specific steps:
the method comprises the following steps: weighing WO349％-51％,NaH2PO438％-42％,BaF27％-10％,Sb2O30％-2％,Na2CO30.5% -2%, uniformly mixing the raw materials in an agate mortar;
step two: melting the mixture for one hour in air at 1050-1100 ℃ by adopting a conventional melting quenching method to prepare the tungsten phosphate glass without eliminating the thermal effect stress;
step three: pouring the molten tungsten phosphate glass without eliminating the thermal effect stress on a brass mould, and cooling to 20-30 ℃;
step four: annealing the tungsten phosphate glass cooled in the third step at 400-420 ℃ for 5 hours to eliminate thermal strain; tungsten phosphate glass is obtained.
3. The method for preparing the tungsten phosphate glass fingerprint acquisition and identification material based on the photochromic effect according to claim 2, wherein the raw materials in the first step have the following weight ratio: WO351％,NaH2PO442％,BaF210％,Sb2O32％,Na2CO32％。
4. The method for preparing the tungsten phosphate glass fingerprint acquisition and identification material based on the photochromic effect according to claim 2, wherein the raw materials in the first step have the following weight ratio: WO349％,NaH2PO438％,BaF27％,Sb2O30％,Na2CO30.5％。
5. The method for preparing the tungsten phosphate glass fingerprint acquisition and identification material based on the photochromic effect according to claim 2, wherein the raw materials in the first step have the following weight ratio: WO350％,NaH2PO440％,BaF28％,Sb2O31％,Na2CO31％。
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110262163.7A CN112979161A (en) | 2021-03-10 | 2021-03-10 | Preparation method and application of tungsten phosphate glass based on photochromic effect |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110262163.7A CN112979161A (en) | 2021-03-10 | 2021-03-10 | Preparation method and application of tungsten phosphate glass based on photochromic effect |
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| CN112979161A true CN112979161A (en) | 2021-06-18 |
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| CN202110262163.7A Pending CN112979161A (en) | 2021-03-10 | 2021-03-10 | Preparation method and application of tungsten phosphate glass based on photochromic effect |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115010365A (en) * | 2022-02-17 | 2022-09-06 | 昆明理工大学 | Photochromic tungsten boron tellurium phosphate glass and preparation method thereof |
| CN115251907A (en) * | 2022-05-09 | 2022-11-01 | 吉林大学 | Fingerprint showing method based on nanosecond laser irradiation |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4222781A (en) * | 1979-08-16 | 1980-09-16 | Corning Glass Works | Optically clear copper halide photochromic glass articles |
| CA1092876A (en) * | 1976-01-30 | 1981-01-06 | Edric Ellis | Photochromic alumino-phosphate glass having dispersed silver halide crystals |
| CN110008830A (en) * | 2019-02-22 | 2019-07-12 | 昆明理工大学 | A kind of WO based on photochromic effect3The preparation method and applications of ceramics |
-
2021
- 2021-03-10 CN CN202110262163.7A patent/CN112979161A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CA1092876A (en) * | 1976-01-30 | 1981-01-06 | Edric Ellis | Photochromic alumino-phosphate glass having dispersed silver halide crystals |
| US4222781A (en) * | 1979-08-16 | 1980-09-16 | Corning Glass Works | Optically clear copper halide photochromic glass articles |
| CN110008830A (en) * | 2019-02-22 | 2019-07-12 | 昆明理工大学 | A kind of WO based on photochromic effect3The preparation method and applications of ceramics |
Non-Patent Citations (2)
| Title |
|---|
| GAËL POIRIER ET AL.: "Photochromic properties of tungstate-based glasses", 《SOLID STATE IONICS》 * |
| 丁佩: "基于材料变色性能的指纹采集方法研究", 《中国优秀硕士学位论文全文数据库 （工程科技Ⅰ辑）》 * |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115010365A (en) * | 2022-02-17 | 2022-09-06 | 昆明理工大学 | Photochromic tungsten boron tellurium phosphate glass and preparation method thereof |
| CN115251907A (en) * | 2022-05-09 | 2022-11-01 | 吉林大学 | Fingerprint showing method based on nanosecond laser irradiation |
| CN115251907B (en) * | 2022-05-09 | 2024-04-26 | 吉林大学 | Fingerprint display method based on nanosecond laser irradiation |
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