阅读说明：本技术 一种升华提纯设备 (Sublimation purification equipment ) 是由 邝常春 马飞越 于 2019-09-12 设计创作，主要内容包括：本发明的升华提纯设备,包括升华提纯模块、加热装置、真空泵以及真空过滤装置,加热装置固定在所述升华提纯模块外侧；真空泵与升华提纯模块连接；真空过滤装置设置在所述升华提纯模块与所述真空泵之间,其包括至少一组过滤部件,每组过滤部件包括第一过滤片和第二过滤片,第一过滤片和第二过滤片上均设有多个滤孔且滤孔互相错位。本发明通过在升华提纯模块和真空泵之间设置真空过滤装置,利用第一过滤片和第二过滤片上的所有滤孔错位,使得真空环境中的有机气体分子可冷凝在过滤片上,保护真空泵；在升华提纯模块的至少两个温区之间设置真空过滤装置,可增加真空环境中的气体分子与过滤片碰撞概率,降低分子平均自由程,增加目标材料的产率。(The sublimation purification equipment comprises a sublimation purification module, a heating device, a vacuum pump and a vacuum filtering device, wherein the heating device is fixed on the outer side of the sublimation purification module; the vacuum pump is connected with the sublimation purification module; the vacuum filtering device is arranged between the sublimation purification module and the vacuum pump and comprises at least one group of filtering components, each group of filtering components comprises a first filtering sheet and a second filtering sheet, and the first filtering sheet and the second filtering sheet are respectively provided with a plurality of filtering holes and the filtering holes are staggered mutually. According to the invention, the vacuum filtering device is arranged between the sublimation purification module and the vacuum pump, and all filtering holes on the first filtering sheet and the second filtering sheet are staggered, so that organic gas molecules in a vacuum environment can be condensed on the filtering sheets, and the vacuum pump is protected; the vacuum filtering device is arranged between at least two temperature zones of the sublimation purification module, so that the collision probability of gas molecules in a vacuum environment and the filter disc can be increased, the average free path of the molecules is reduced, and the yield of target materials is increased.)

1. A sublimation purification device is characterized by comprising a sublimation purification module, a heating device, a vacuum pump and a vacuum filtering device, wherein the heating device is fixed at the outer side of the sublimation purification module and divides the sublimation purification module into at least three temperature zones, and the temperatures of the temperature zones are in a sequentially decreasing trend; the vacuum pump is connected with the sublimation purification module and is used for providing a high vacuum environment for material sublimation purification; the vacuum filtering device is arranged between the sublimation purification module and the vacuum pump and comprises at least one group of filtering components, each group of filtering components comprises a first filtering sheet and a second filtering sheet, a plurality of filtering holes are formed in the first filtering sheet and the second filtering sheet, the first filtering sheet is connected with the second filtering sheet, and the filtering holes in the first filtering sheet and the second filtering sheet are staggered mutually.

2. The sublimation purification apparatus of claim 1, wherein at least one gasket is disposed between the first filter sheet and the second filter sheet, the gasket being hollowed out.

3. The sublimation purification apparatus of claim 2, wherein the first filter disc, the second filter disc and the gasket are provided with two butt holes at the outer edge, and the butt holes connect the first filter disc, the second filter disc and the gasket in series and/or connect multiple groups of filter components in series through butt pins.

4. Sublimation purification apparatus according to claim 2, wherein the vacuum filtration device is integrally formed.

5. The sublimation purification apparatus of claim 1, wherein the filter pores have a pore size ranging from 1mm to 1/10 mm of the outer diameter of the filter sheet.

6. Sublimation purification apparatus according to claim 1, wherein the vacuum filtration device is provided between at least two temperature zones.

7. The sublimation purification apparatus of claim 1, wherein the vacuum pump is a molecular pump.

Technical Field

The invention relates to a small molecular material sublimation device, in particular to sublimation purification equipment.

Background

At present, Organic small molecular materials are widely applied to novel electronic industries such as Organic Light-Emitting Diode (OLED) display, flexible sensors and Organic solar cells. The common characteristic of these organic small molecule materials is that a thin film with controllable thickness/shape can be formed on the substrate by evaporation, which is similar to the mainstream semiconductor production process at present. The performance of organic electronic devices and the purity of materials during evaporation are closely related, so the preparation process of high-purity organic materials has been receiving attention from the industry, and the most common purification method of organic materials at present is sublimation purification, i.e. separation and purification by using the difference between the gasification temperature of target materials and the gasification temperature of impurities.

The purification equipment main body on the market at present comprises a multi-temperature-zone tube furnace, as shown in fig. 1, the tube is generally made of quartz, the inside of an outer tube 3 needs to be vacuumized by a vacuum pump, the inside of the outer tube is divided into a plurality of short-sized inner tubes 2 which are connected with each other, a raw material 1a to be sublimated and purified is placed in a first short inner tube 2 at the left end, when the temperature of a raw material sublimation zone 100 exceeds a sublimation point, a target material 1b is gasified and diffused out of the tube, and is deposited on the inner wall of the inner tube 2 in a target material deposition zone 200, and impurities 1c are deposited on the inner wall of the. The device has simple design and low cost, but has a plurality of problems in the actual operation process: firstly, high boiling point impurities which are not sublimated in the raw material 1a move along with the air flow and are deposited in the target material deposition area 200, so that the purity of the product is reduced; secondly, the target material 1b moves with the gas flow to reach the rear end of the target material deposition region 200, as shown in fig. 1, even confused with the impurity 1c of the impurity deposition region 300, reducing the yield; thirdly, since the molecular mean free path of the gas molecules moving at high speed in the sublimation purification apparatus under high vacuum condition is much larger than the size of the container, if the gas molecules are not condensed quickly, a large amount of impurities 1c and the target material 1b move to the vacuum pump providing vacuum environment, and damage the vacuum pump, therefore, certain measures must be taken to protect the vacuum pump. In practical application, the vacuum pump is protected mainly through the combination that sets up three kinds of modes such as microporous filter screen, liquid nitrogen cooling device and sublimation purification pipe and vacuum pump right angle connection between sublimation purification pipe and vacuum pump in prior art, wherein, there is following problem in the mode that adopts microporous filter screen liquid feeding nitrogen cold trap: the micro-machined filter screen is expensive and has poor gas molecule filtering effect, so that a large amount of molecules enter the liquid nitrogen cold trap to be rapidly condensed after being filtered by the filter screen, but a small amount of molecules still enter the vacuum pump, the micro-porous filter screen is easy to block, the liquid nitrogen cold trap is expensive in manufacturing cost, needs to be frequently cleaned, and is short in maintenance period; the mode of connecting the vacuum pump and the vacuum pipeline at right angle and adding the liquid nitrogen cold trap also has the problems of high manufacturing cost, large volume and short maintenance period of the liquid nitrogen cold trap. In addition, the vacuum pump is protected in a mode that a sensor automatically detects whether the vacuum degree meets the set requirement or not to automatically turn off the vacuum pump in the prior art, and the method cannot be used for actual production at present.

Accordingly, the prior art is yet to be improved and developed.

Disclosure of Invention

The invention aims to provide sublimation purification equipment, aiming at solving the problem that in the existing sublimation purification process of small molecular materials, impurities with high boiling point or target materials move to the rear end of a set area along with air flow, so that the purity of products is reduced; and the problem of impurities and target materials moving with the gas stream to the vacuum pump damaging the vacuum pump.

In order to solve the problems, the technical scheme of the invention is as follows:

A sublimation purification device comprises a sublimation purification module, a heating device, a vacuum pump and a vacuum filtering device, wherein the heating device is fixed outside the sublimation purification module and divides the sublimation purification module into at least three temperature zones, and the temperatures of the temperature zones are in a sequentially decreasing trend; the vacuum pump is connected with the sublimation purification module and is used for providing a high vacuum environment for material sublimation purification; the vacuum filtering device is arranged between the sublimation purification module and the vacuum pump and comprises at least one group of filtering components, each group of filtering components comprises a first filtering sheet and a second filtering sheet, a plurality of filtering holes are formed in the first filtering sheet and the second filtering sheet, the first filtering sheet is connected with the second filtering sheet, and the filtering holes in the first filtering sheet and the second filtering sheet are staggered mutually.

The sublimation purification equipment is characterized in that at least one gasket is arranged between the first filter sheet and the second filter sheet, and the middle of the gasket is hollowed.

The sublimation purification equipment is characterized in that the outer edges of the first filter disc, the second filter disc and the gasket are respectively provided with two butt joint holes, and the first filter disc, the second filter disc and the gasket are connected in series through butt joint pins and/or a plurality of groups of filter components are connected in series through the butt joint holes.

The sublimation purification apparatus described above, wherein the vacuum filtration device is integrally formed.

The sublimation purification equipment is characterized in that the pore diameter of the filter pores ranges from 1mm to 1/10 of the outer diameter of the filter sheet.

The sublimation purification equipment is characterized in that the vacuum filter device is arranged between at least two temperature zones.

The sublimation purification equipment, wherein the vacuum pump is a molecular pump.

The beneficial effects of the invention include: according to the invention, the vacuum filtering device is arranged between the sublimation purification module and the vacuum pump, the vacuum filtering device comprises a plurality of groups of combined filtering components of the first filtering sheet and the second filtering sheet, and all filtering holes on the first filtering sheet and the second filtering sheet are staggered, so that large-particle solids can be filtered, organic gas molecules in a vacuum environment can collide with the filtering sheets at any angle when passing through the filtering sheets and finally are condensed on the filtering sheets, the molecular pump is prevented from being damaged by the condensation of the gas molecules on the molecular pump, and the area between the vacuum pump and the vacuum filtering device is not required to be maintained and cleaned frequently; the vacuum filtering device is arranged between at least two temperature zones of the sublimation purification module, so that the collision probability of gas molecules in a vacuum environment and the filter discs can be increased, the average free path of the molecules is reduced, the organic molecule gases with different condensation points can selectively pass through the filter discs, the yield of target materials is increased, at least one annular gasket with a hollow middle part is arranged between the first filter disc and the second filter disc, the molecules can be reduced to flow to the outer wall through the thin gap between the first filter disc and the second filter disc, and the molecules are deposited on the outer wall and are difficult to process.

Drawings

Fig. 1 is a schematic structural diagram of a small molecule material sublimation purification apparatus in the prior art.

Fig. 2 is a schematic structural view of a first filter sheet of a vacuum filtration device in the sublimation purification apparatus of embodiment 1 of the invention.

Fig. 3 is a schematic structural view of a second filter sheet of the vacuum filtration device in the sublimation purification apparatus of embodiment 1 of the invention.

Fig. 4 is a schematic structural view of a gasket of a vacuum filtration device in the sublimation purification apparatus of embodiment 1 of the invention.

Fig. 5 is a partial structural side view of the sublimation purification apparatus of embodiment 1 of the invention.

Fig. 6 is a partial structural side view of a sublimation purification apparatus of embodiment 2 of the invention.

FIG. 7 is a partial structural side view of a sublimation purification apparatus of embodiment 3 of the invention.

Fig. 8 is a schematic diagram of experimental design of filtration performance of the vacuum filtration device in the sublimation purification apparatus of example 2 of the present invention.

Fig. 9 is a graph comparing the results of CPD material experiments for the filtering performance experiments of the vacuum filtering device in the sublimation purification apparatus of example 2 of the present invention.

Fig. 10 is a graph comparing the experimental results of BBSN material for the filtration performance experiment of the vacuum filtration device in the sublimation purification apparatus of example 2 of the present invention.

Fig. 11 is an experimental design diagram of the filtration performance of the vacuum filtration device in the sublimation purification apparatus of example 3 of the invention.

Fig. 12 is a graph showing a first set of experimental results on the filtering performance of the vacuum filtering device in the sublimation purifying apparatus of example 3 of the invention.

Fig. 13 is a second set of experimental result graphs of the filtering performance of the vacuum filtering device in the sublimation purifying apparatus of example 3 of the present invention.

Fig. 14 is a third set of experimental result graphs of the filtering performance of the vacuum filtering device in the sublimation purifying apparatus of example 3 of the present invention.

Description of reference numerals: 100. a raw material sublimation zone; 200. a target material deposition zone; 300. an impurity deposition region; 1a, raw materials; 1b, a target material; 1c, impurities; 2. an inner tube; 3. an outer tube; 10. a first filter sheet; 20. a second filter sheet; 30. a gasket; 40. filtering holes; 50. a butt joint hole; 60. a non-porous stainless steel baffle plate; 70. and (4) a filtering device.

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the accompanying drawings are illustrative only for the purpose of explaining the present invention, and are not to be construed as limiting the present invention.

In the description of the present invention, it is to be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. indicate orientations or positional relationships based on those shown in the drawings, and are used merely for convenience of description and for simplicity of description, and do not indicate or imply that the device or element so referred to must have a particular orientation, be constructed in a particular orientation, and be operated, and thus should not be considered as limiting the present invention. In the description of the present invention, it should be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; may be mechanically connected, may be electrically connected or may be in communication with each other; either directly or indirectly through intervening media, either internally or in any other relationship. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

In the present invention, unless otherwise expressly stated or limited, "above" or "below" a first feature means that the first and second features are in direct contact, or that the first and second features are not in direct contact but are in contact with each other via another feature therebetween. Also, the first feature being "on," "above" and "over" the second feature includes the first feature being directly on and obliquely above the second feature, or merely indicating that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature includes the first feature being directly under and obliquely below the second feature, or simply meaning that the first feature is at a lesser elevation than the second feature.

The following disclosure provides many different embodiments or examples for implementing different features of the invention. To simplify the disclosure of the present invention, the components and arrangements of specific examples are described below. Of course, they are merely examples and are not intended to limit the present invention. Furthermore, the present invention may repeat reference numerals and/or letters in the various examples, such repetition is for the purpose of simplicity and clarity and does not in itself dictate a relationship between the various embodiments and/or configurations discussed. In addition, the present invention provides examples of various specific processes and materials, but one of ordinary skill in the art may recognize applications of other processes and/or uses of other materials.

The sublimation purification equipment comprises a sublimation purification module, a heating device, a vacuum pump and a vacuum filtering device, wherein the heating device is fixed on the outer side of the sublimation purification module, and divides the sublimation purification module into at least three temperature zones, in practical application, the sublimation purification equipment can comprise a raw material sublimation zone 100, at least one target material deposition zone 200 and at least one impurity deposition zone 300, the temperatures of the temperature zones are in a sequentially decreasing trend from the raw material sublimation zone 100, and the sublimation purification module can be formed by arranging a plurality of mutually connected short-size inner tubes 2 in an outer tube 3; the vacuum pump is connected with the outer tube 3 of the sublimation purification module and is used for providing a high vacuum environment for material sublimation purification, and in practical application, the vacuum pump is generally a molecular pump; the vacuum filtering device is arranged between the sublimation purification module and the vacuum pump; the vacuum pump is connected with the sublimation purification module and is used for providing a high vacuum environment for material sublimation purification; the vacuum filtering device is arranged between the sublimation purification module and the vacuum pump and comprises at least one group of filtering components, each group of filtering components comprises a first filtering sheet 10 and a second filtering sheet 20, the first filtering sheet 10 and the second filtering sheet 20 are respectively provided with a plurality of filtering holes 40, the first filtering sheet 10 is connected with the second filtering sheet 20, the filtering holes 40 on the first filtering sheet 10 and the second filtering sheet 20 are staggered, furthermore, the aperture ranges of the filtering holes 40 of the first filtering sheet 10 and the second filtering sheet 20 are respectively 1mm to 1/10 of the outer diameter of the filtering sheet, compared with the filtering holes of the traditional microporous filtering net, the working principle of the filtering hole 40 of the vacuum filtering device is different from that of the traditional filtering net: the traditional filter screen aims at blocking particle powder, so that the micropore filter screen cannot block gas from passing through a sublimation purification module, and the gasified organic molecules moving at high speed are required to be subjected to heat exchange with a low-temperature container wall in order to stop moving and condensing, so that the kinetic energy of the molecules is reduced when the molecules moving at high speed collide with the container wall at a lower temperature according to the conservation of the active energy, and part of the energy is transferred to the container wall; in addition, the molecular mean free path is also a factor influencing the condensation of gasified organic molecules, the meaning of the molecular mean free path is the mean path between two collisions of molecules, the molecular mean free path is far larger than the size of a container under the high vacuum condition in a sublimation purification module, so that the condensation of gas molecules can be realized by reducing the molecular mean free path, the vacuum filter device of the invention realizes the filtration by arranging a plurality of groups of first filter sheets 10 and second filter sheets which are connected with each other and have staggered filter holes 40 according to the gas diffusion rule and the gas condensation condition, namely, the molecular mean free path is reduced to force the condensation of gas molecules to realize the filtration, therefore, the aperture is only in the range of common naked eyes, namely, the filter holes 40 can be obtained only by common processing technology on the market, the cost is low, while the traditional microporous filter screen needs more precise micropore processing and has large processing difficulty, the cost is much greater than the vacuum filtration device of the present invention. As shown in fig. 2 and fig. 3, in embodiment 1, two different filter structures are designed, and by flexible matching of two fittings and matching with a certain temperature, the collision probability of gas molecules and the fittings can be effectively increased, and the molecular mean free path is reduced, so that organic molecule gases with different condensation points can selectively pass through the vacuum filter device of the present invention, and different combinations can be applied to various scenes to achieve different purposes. Further, in practical application, at least one gasket 30 is arranged between the first filter sheet 10 and the second filter sheet 20, and the gasket 30 is in a ring shape with a hollow center, and is used for preventing gas molecules from flowing out from a gap between the first filter sheet 10 and the second filter sheet 20 and depositing on the inner wall of the outer tube 3, which is difficult to process. In practical applications, the first filter sheet 10, the second filter sheet 20 and the gasket 30 of the filter element have various connection modes, in embodiment 1, two butt holes 50 are respectively formed at the outer edges of the first filter sheet 10, the second filter sheet 20 and the gasket 30, the first filter sheet 10, the second filter sheet 20 and the gasket 30 can be fixed in series by butt pins, and meanwhile, multiple groups of filter elements can be fixed in series to form the vacuum filter device of the present invention. In addition, the vacuum filter device of the present invention can also be integrally formed through a process.

As shown in fig. 5, in embodiment 1, the vacuum filtering device of the sublimation purification apparatus of the invention is disposed in the normal temperature region between the sublimation purification module and the vacuum pump, in practical applications, almost all organic small molecule materials used for OLED display, flexible sensor, and organic solar cell are solid at normal temperature, so as long as multiple sets of interconnected filtering components are disposed in the normal temperature region, and the filtering components are combined by the first filtering sheet 10 and the second filtering sheet 20, gas molecules will continuously collide with the filtering sheets, and finally heat exchange is completed and condensed on the filtering sheets, in this embodiment, a gasket 30 is further disposed between the first filtering sheet 10 and the second filtering sheet 20 to prevent gas from flowing out from the gap between the first filtering sheet 10 and the second filtering sheet 20 and depositing on the inner wall of the outer tube 3; compared with the traditional microporous filter screen, the vacuum filter device has the advantages that the material consumption is greatly reduced, the area between the expensive molecular pump and the filter screen does not need to be maintained and cleaned frequently, only the vacuum filter device needs to be cleaned, the operation is simple, and the use is convenient. In practical application, a vacuum filtering device is arranged between at least two temperature zones in the sublimation purification equipment, as shown in fig. 6, the vacuum filtering device can be arranged between the target material deposition zone 200 and the low-boiling point impurity deposition zone 300, because the low-boiling point impurities can flow through the target material deposition zone 200 along with the air flow, the vacuum filtering device needs certain fluidity, and the vacuum filtering device formed by combining filtering components of the first filtering sheet 10, the gasket 30 and the second filtering sheet 20 in proper quantity is arranged between the target material deposition zone 200 and the low-boiling point impurity deposition zone 300, so that the target product can not pass through the vacuum filtering device and the low-boiling point impurities can pass through, the yield of the product is improved, and the problems that the target product flows through the target material deposition zone 200 along with the air flow and the yield is reduced are solved. In example 2 shown in fig. 6, four sets of filter elements formed by combining the first filter sheet 10, the gasket 30 and the second filter sheet 20 are disposed between two temperature zones of the target material deposition zone 200 and the impurity deposition zone 300, wherein one gasket 30 is disposed between the first filter sheet 10 and the second filter sheet 20, the gasket 30 is mainly disposed to reduce the flow of molecules to the outer wall through the slits between the first filter sheet 10 and the second filter sheet 20, in practical applications, the flow of molecules to the inside of the tube and the flow of molecules to the outer wall are a set of opposite reactions, if only the first filter sheet 10 and the second filter sheet 20 are used in combination, the flow of molecules in the tube is blocked, the probability of molecules flowing from the slits between the filter sheets to the outer wall is increased, and the addition of the gasket 30 between the first filter sheet 10 and the second filter sheet 20 can greatly increase the flow of gas in the inner tube, thereby reducing the probability of molecules diffusing to the outer wall through the slits between the filter sheets, resulting in a reduced yield and difficulty in handling the material deposited on the outer wall.

As shown in fig. 7, the vacuum filtration apparatus of the present invention may be disposed between the raw material sublimation region 100 and the target material deposition region 200, and since most of the raw material flows out from the raw material sublimation region 100, the filtration apparatus needs to have a large fluidity in the tube direction to prevent molecules from flowing to the outer wall through the slit between the first filter sheet 10 and the second filter sheet 20, so that the filter member therein should be able to block both high-boiling impurities and easily pass the vaporizable substances, as in embodiment 3 shown in fig. 10, a vacuum filtration apparatus in which a plurality of gaskets 30 are added between the first filter sheet 10 and the second filter sheet 20 in combination is disposed between the raw material sublimation region 100 and the target material deposition region 200, four gaskets 30 are provided in embodiment 3, so that the high-boiling impurities cannot pass through the vacuum filtration apparatus, and the low-boiling substances easily pass through the vacuum filtration apparatus, so as to solve the problem that the non-sublimed high boiling point impurities are deposited in the target material deposition area 200 along with the movement of the air flow, and the purity of the product is reduced.

In order to verify the filtering performance and effect of the vacuum filtering device of the sublimation purification apparatus of the present invention, the following experiments were designed, as shown in fig. 8, 9 and 10, and the experimental design principle is as follows: the filtering device 70 is arranged between the target material collecting area 200 and the impurity deposition area 300, the filtering device 70 can be replaced between the existing filtering screen and the vacuum filtering device of the invention, then the short inner pipe 3 is arranged, the nonporous stainless steel baffle 60 is connected, finally the set material is sublimated in the sublimation purification equipment, the material passes through the filtering device 70, the filtering effect of the existing filtering screen and the high-efficiency vacuum filtering device of the invention is compared by taking the material condensed and deposited on the nonporous stainless steel baffle 60 as the standard, and the quality increase of the nonporous stainless steel baffle 60 is taken as the standard for evaluating the performance of the filtering device in the experiment.

The first set of experiments employed an existing filter screen, which was similar to the first filter 10 and was directly replaced with the first filter 10; testing materials and quality: CPD-G1906251A1: 10.0546G; BBSN-start:6.0026 g.

The second set of experiments employed the vacuum filtration apparatus of the present invention, which was assembled and connected using two identical sets of filter elements (connected in the order of first filter sheet 10, gasket 30, second filter sheet 20, gasket 30, first filter sheet 10, gasket 30, second filter sheet 20); testing materials and quality: CPD-G1906251A1: 10.0535G; BBSN-start:6.0027 g.

the experimental results are shown in fig. 9 and 10, wherein fig. 9 is a graph comparing the experimental results of the CPD test material, fig. 10 is a graph comparing the experimental results of the BBSN test material, the left side of the graph is the experimental results of the existing filter screen, and the right side is the experimental results of the vacuum filter apparatus of the present invention, it can be clearly seen that after the vacuum filter apparatus of the present invention is used, the gas molecules are almost completely condensed on the filter apparatus, the non-porous stainless steel baffle 60 is much less than the material deposited on the existing filter screen, and the filtering effect is better than the existing filter screen. Furthermore, in two groups of experiments, as can be seen by weighing comparison, in the experimental result of the CPD test material, the added mass of the left nonporous stainless steel baffle 60 is 0.0116g, while the added mass of the right nonporous stainless steel baffle 60 is only 0.0003g, so that the vacuum filtration device of the present invention improves the filtration effect by 38.7 times; in the result of using BBSN as the test material, the added mass of the left imperforate stainless steel baffle 60 is 0.0032g, while the added mass of the right imperforate stainless steel baffle 60 is only 0.0001g, and the vacuum filtration apparatus of the present invention improves the filtration effect by 32 times. Therefore, the vacuum filter device has better filtering performance than the prior filter screen.

In addition, in order to verify the filtering performance and effect of the vacuum filtering device of the sublimation purification apparatus of the invention, the following experiment is also designed, as shown in fig. 11, the experimental design principle is as follows: the vacuum filter device 70 of the invention with changed combination is placed between the raw material sublimation area 100 and the target material collection area 200, wherein, the raw material sublimation area 100 and the target material collection area 200 can be both two short inner pipes 2, and a group of fixed filter devices 70 is arranged behind the target material collection area 200, the fixed filter devices 70 are used for blocking gas molecules from flowing through the target material collection area 200, and condensing and depositing are carried out in the area outside the target material collection area 200, thereby the filtering performance and the effect of the vacuum filter device formed by the combination of the filter components between the raw material sublimation area 100 and the target material collection area 200 can be known by observing the material deposition condition of the target material collection area 20 through naked eyes. Wherein, by using liq with the mass of 10.8993g as a test material, a blank is set between the raw material sublimation area 100 and the target material collection area 200 in the first set of experiments, and fig. 12 is an experimental result thereof; the second set of experiments set up a combination of 1 first filter sheet 10 and 4 gaskets 30 between 1 second filter sheet 20 between the raw material sublimation area 100 and the target material collection area 200, and fig. 13 is the experimental result thereof; the third set of experiments arranges the combination of 1 first filter sheet 10, 4 gaskets 30, 1 second filter sheet 20, 4 gaskets 30 and 1 first filter sheet 10 in sequence between the raw material sublimation area 100 and the target material collection area 200, and fig. 14 is the experimental result thereof. As can be understood from comparing fig. 12, 13 and 14, as the number of the filter units increases, the effect of the vacuum filter unit made up thereof becomes more excellent, and in the third set of experiments, the short pipe in which the target material collecting region 200 is located is completely cleaned, the raw material 1a in the short pipe in which the raw material sublimation region 100 is located is also sublimated more thoroughly than the first and second sets of experiments, and it can be seen that the combined vacuum filter unit having the raw material sublimation region 100 and the target material collecting region 200 in the order of 1 first filter sheet 10, 4 spacers 30, 1 second filter sheet 20, 4 spacers 30 and 1 first filter sheet 10 has excellent filtering performance, and most of the sublimated material has been condensed on the vacuum filter unit. Therefore, the vacuum filtering device provided by the invention has excellent filtering performance and effect according to the gas diffusion rule and the gas condensation condition.

And proved by verification, the sublimation purification equipment provided by the invention is a vacuum filter device arranged in a normal temperature region between the sublimation purification module and the vacuum pump, and can completely replace a cooling device used for condensing gas molecules to protect the vacuum pump in the traditional sublimation purification equipment. In addition, the vacuum filter device can be combined with a cooling device, and the filter device is combined with low temperature, so that the filter performance of the vacuum filter device is greatly improved, impurity gas molecules or target material gas molecules are more effectively condensed, and a molecular pump is protected. According to the invention, the vacuum filtering device is arranged between the sublimation purification module and the vacuum pump, the vacuum filtering device comprises a plurality of groups of combinations of the first filtering sheet and the second filtering sheet, and all filtering holes on the first filtering sheet and the second filtering sheet are staggered, so that large-particle solids can be filtered, organic gas molecules in a vacuum environment can collide with the filtering sheets at any angle when passing through the filtering sheets and finally are condensed on the filtering sheets, the gas molecules are prevented from being condensed on the molecular pump to damage the molecular pump, the region between the vacuum pump and the vacuum filtering device is not required to be maintained and cleaned frequently, and a cooling device for condensing the gas molecules to protect the vacuum pump in the traditional sublimation purification equipment can be completely replaced, so that the vacuum pump has the advantages of small volume, simplicity and convenience in operation and low cost; the vacuum filtering device is arranged between at least two temperature zones of the sublimation purification module, so that the collision probability of gas molecules in a vacuum environment and the filter discs can be increased, the average free path of the molecules is reduced, the organic molecule gases with different condensation points can selectively pass through the filter discs, the yield of target materials is increased, at least one annular gasket with a hollow middle part is arranged between the first filter disc and the second filter disc, the molecules can be reduced to flow to the outer wall through the thin gap between the first filter disc and the second filter disc, and the molecules are deposited on the outer wall and are difficult to process.

It is to be understood that the invention is not limited to the examples described above, but that modifications and variations may be effected thereto by those of ordinary skill in the art in light of the foregoing description, and that all such modifications and variations are intended to be within the scope of the invention as defined by the appended claims.