CN113150355A

CN113150355A - Production equipment and process of nitrocellulose membrane

Info

Publication number: CN113150355A
Application number: CN202110197777.1A
Authority: CN
Inventors: 宋亚琳; 陈立梅
Original assignee: Shenzhen Connecticut Biotechnology Co ltd
Current assignee: Shenzhen Connecticut Biotechnology Co ltd
Priority date: 2021-02-22
Filing date: 2021-02-22
Publication date: 2021-07-23
Anticipated expiration: 2041-02-22
Also published as: CN113150355B

Abstract

The utility model relates to a production facility and technology of nitrocellulose membrane relates to the technical field of nitrocellulose membrane production, including the surface treatment subassembly that is used for nitrocellulose membrane surface treatment, the surface treatment subassembly includes mutually independent and adjacent first surface treatment groove and the second surface treatment groove that sets up, and the tank bottom of first surface treatment groove is equipped with first liquid outlet, and the tank bottom of second surface treatment groove is equipped with the second liquid outlet. This application is through setting up first surface treatment groove and first surface treatment groove for in the nitrocellulose membrane production process, be convenient for change PBS treatment fluid, can uninterruptedly produce nitrocellulose membrane, improve nitrocellulose membrane's quality.

Description

Production equipment and process of nitrocellulose membrane

Technical Field

The application relates to the technical field of nitrocellulose membrane production, in particular to a production device and a production process of a nitrocellulose membrane.

Background

The Nitrocellulose (NC) membrane is a main component of an in vitro diagnostic reagent (immunochromatography), is a carrier of a quality control line C line and a detection line T line, is also a region where an antibody reacts with an antigen, and the quality of the Nitrocellulose (NC) membrane directly influences the performance index of the in vitro diagnostic reagent. Nitrocellulose membranes have been widely used in the fields of biochemistry and molecular biology, particularly in molecular hybridization, immunoblotting, cell culture, and medical diagnostics.

Nitrocellulose membrane is one of the main materials of the new coronavirus (antibody) detection reagents which are well known at present. Due to the global spread of epidemic situations, the antibody reagent is greatly demanded, the demand of the nitrocellulose membrane is increased by one time, and the current market state meets the demand. The index of the enterprises which can produce the nitrocellulose membrane at present can be counted.

The main preparation processes for preparing the nitrocellulose membrane at present comprise: preparing raw materials, filtering, coating and forming, adding a surfactant, drying, rolling and cutting.

However, in the preparation process of adding the surfactant treatment solution, the nitrocellulose membrane is soaked in the treatment solution, and the surface of the nitrocellulose membrane is treated, so that the quality of the nitrocellulose membrane is ensured, and the production continuity of the nitrocellulose membrane is ensured. After the treatment fluid is used for a period of time, the treatment fluid needs to be replaced with new treatment fluid at intervals in the production process, solute is supplemented to the treatment fluid in time, and impurities are reduced. When using single cistern to handle nitrocellulose membrane, in order to guarantee production efficiency, do not stop and trade liquid, only can change two-thirds of treating fluid volume in the single cistern at every turn, and the impurity that the treating fluid that does not change in the single cistern contained can not discharge in time, and the treating fluid that does not change completely is used through lasting incessant production, easily causes the impurity that the nitrocellulose membrane surface adheres to there is the treating fluid, influences the quality of nitrocellulose membrane.

Disclosure of Invention

In order to improve the quality of the nitrocellulose membrane, the application provides a production device of the nitrocellulose membrane, which adopts the following technical scheme:

the utility model provides a production facility of nitrocellulose membrane, is including the surface treatment subassembly that is used for nitrocellulose membrane surface treatment, and the surface treatment subassembly includes mutually independent and adjacent first surface treatment groove and the second surface treatment groove that sets up, and the tank bottom of first surface treatment groove is equipped with first liquid outlet, and the tank bottom of second surface treatment groove is equipped with the second liquid outlet.

By adopting the technical scheme, the PBS treatment liquid can be always kept in any one of the first surface treatment tank and the second surface treatment tank. When the surface of the nitrocellulose membrane is treated, the nitrocellulose membrane sequentially passes through the first surface treatment groove and the second surface treatment groove, when PBS treatment liquid in the first surface treatment groove is replaced, newly-configured PBS treatment liquid is added into the second surface treatment groove, then the PBS treatment liquid in the first surface treatment groove is discharged through the first liquid outlet, and at the moment, the surface treatment of the nitrocellulose membrane is completed by the treatment of the PBS treatment liquid in the second surface treatment groove. PBS treatment liquid in the first surface treatment groove and the second surface treatment groove is discontinuously and alternately used, so that the cellulose nitrate film is uninterruptedly produced, the quality of the cellulose nitrate film is improved, and the production efficiency is improved.

Preferably, the tank bottom of the first surface treatment tank is obliquely arranged, the first liquid outlet is positioned at the low end of the tank bottom of the first surface treatment tank, a first guide roller is arranged near the tank bottom of the first surface treatment tank, the second surface treatment tank has the same structure as the first surface treatment tank, a second guide roller is arranged near the tank bottom of the second surface treatment tank, and gaps are reserved between the first guide roller and the tank bottom of the first surface treatment tank and between the second guide roller and the tank bottom of the second surface treatment tank.

By adopting the technical scheme, the bottoms of the first surface treatment tank and the second surface treatment tank are both obliquely arranged, so that the used PBS treatment liquid is convenient to discharge when the PBS treatment liquid is replaced; the nitrocellulose membrane sequentially passes through the first guide roller and the second guide roller below the first surface treatment groove and the second surface treatment groove, so that the nitrocellulose membrane is completely immersed in PBS treatment liquid, the reaction of the nitrocellulose membrane and the PBS treatment liquid is more thorough, and the quality of the nitrocellulose membrane is improved.

Preferably, the surface treatment assembly further comprises a hot water tank, the hot water tank is located on one side, away from the second surface treatment tank, of the first surface treatment tank, a circulating tank is arranged on one side of the hot water tank, a partition plate is arranged between the circulating tank and the hot water tank, a water permeable hole is formed in the partition plate, and filter cloth is arranged at the water permeable hole.

By adopting the technical scheme, the nitrocellulose membrane can conveniently finish the surface impurity treatment of the nitrocellulose membrane through the hot water tank, and meanwhile, the bacterial generation in the hot water tank can be reduced, and the quality of the nitrocellulose membrane can be improved; link up through the hole of permeating water between circulation tank and the hot-water tank, for the hot-water tank provides homothermal hot water, avoid because the temperature is unstable to cause the inhomogeneous phenomenon of nitrocellulose membrane processing in hot water, the setting of filter cloth then can further reduce in the circulation tank impurity flow in the hot-water tank.

Preferably, the hot water tank is provided with a supporting component for supporting the filter cloth at a position close to the water permeable hole, the supporting component comprises a supporting rod and a connecting rod connected to the end of the supporting rod, two ends of the filter cloth are respectively fixedly connected with the corresponding connecting rods, and the end of the filter cloth close to the supporting rod is fixed on the supporting rod.

Through adopting above-mentioned technical scheme, the supporting component sets up on the hot-water tank, and the filter cloth passes through the bracing piece and the connecting rod is fixed on the hot-water tank, and the filter cloth expandes through the supporting component, and the filter cloth is close to the hole setting of permeating water, has reduced in the circulation inslot impurity flow direction hot-water tank.

Preferably, a communicating piece is further connected between the hot water tank and the circulating tank, the communicating piece comprises a water pump, a water pumping pipe and a water delivery pipe, one end of the water pumping pipe extends into the lower end of the inner wall of the hot water tank, and the other end of the water pumping pipe is connected to the water pump; one end of the water supply pipe is connected with the water pump, and the other end of the water supply pipe is communicated with the circulating groove.

Through adopting above-mentioned technical scheme, through the setting of water pump, drinking-water pipe and flow pipe, the hot water in the hot-water tank realizes flowing with the hot water in the circulating tank in real time, and hot water keeps the constant temperature state of settlement in real time in the hot-water tank for the same to the processing condition of whole nitrocellulose membrane in the hot-water tank, guarantee the quality of whole nitrocellulose membrane.

Preferably, the water permeable hole is provided at a position more than two thirds of the depth of the hot water tank.

Through adopting above-mentioned technical scheme, realize the circulation of hot water in circulation tank and the hot water inslot hot water through the hole of permeating water for hot water in the circulation tank flows in the hot water groove in real time, and the position in the hole of permeating water simultaneously can also guarantee to soak in hot water completely through the nitrocellulose membrane of hot water groove.

In a second aspect, the present application provides a process for producing a nitrocellulose membrane, which adopts the following technical scheme:

a process for preparing the nitrocellulose membrane includes such steps as treating the surface of nitrocellulose membrane,

coating and forming a cellulose nitrate membrane film paddle;

the coating-formed nitrocellulose membrane (NC membrane) sequentially passes through a hot water tank, a first surface treatment tank and a second surface treatment tank;

wherein the PBS treatment liquid is added into the first surface treatment groove or the second surface treatment groove;

the time of the NC film passing through the hot water tank is more than 1 min.

By adopting the technical scheme, the surface treatment of the NC film is completed through the hot water tank, the first surface treatment tank and the second surface treatment tank, so that the quality of the NC film is improved; the time of the NC membrane passing through the hot water tank is more than 1min, so that impurities on the surface of the NC membrane can be more treated.

Preferably, the temperature of the hot water treatment is 60 ℃ to 66 ℃.

By adopting the technical scheme, the impurities of the NC membrane can be thoroughly washed away by adding the hot purified water, and the components of the treatment solution required by the surface of the subsequent treatment membrane are protected; the hot water temperature of 60-66 ℃ is helpful for dissolving unreacted substances or impurities attached on the NC membrane and preventing the NC membrane from being polluted by bacteria generated in the water tank.

Preferably, a staged baking mode is adopted in the coating and forming process of the nitrocellulose membrane, the nitrocellulose membrane sequentially passes through different temperature stages, the temperature is raised from 19-21 ℃ to 34-36 ℃, and the relative humidity of air is 40% -65%.

By adopting the technical scheme, after the NC film is coated and formed, the volatilization speed of the solvent in the NC film is controlled in a staged heating mode, the humidity of air is controlled, the content of air bubbles in the film paddle is reduced, and the high-quality NC film is convenient to obtain.

In summary, the present application has the following beneficial effects:

1. the surface treatment assembly of the nitrocellulose membrane production equipment is provided with the first surface treatment groove and the second surface treatment groove, and when groove liquid needs to be replaced, the treatment liquid in the first surface treatment groove and the second surface treatment groove is replaced and used alternately, so that the nitrocellulose membrane can be continuously immersed in the treatment liquid in production, and the production efficiency and the quality of NC membrane products are greatly improved.

2. Compared with a single treatment liquid tank, the treatment liquid tank is directly used for cleaning and treating, so that the concentration of non-reactant of the NC membrane in the treatment liquid can be rapidly increased, and the original components of the treatment liquid are changed. The added hot purified water can thoroughly wash off impurities of the NC membrane, protect treatment liquid components required by the surface of a subsequent treatment membrane and greatly reduce bubbles or impurities on the NC membrane.

3. The hot water treatment process adopts 63 +/-3 ℃ in the application, and is beneficial to dissolving unreacted substances or impurities attached to the NC membrane. Meanwhile, the antibacterial effect can be effectively achieved, the NC membrane is prevented from being polluted by bacteria growing in the hot water tank, and the quality of the NC membrane is improved.

4. In the preparation technology of this application that adopts the NC membrane, the NC membrane has overcome when changing PBS treatment fluid through first surface treatment groove and second surface treatment groove, and PBS treatment fluid is changed and is not thoroughly to the influence of the processing on NC membrane surface, and this application preparation technology does not influence the NC membrane treatment effect when changing treatment fluid, has guaranteed the quality of NC membrane and the continuity of production.

Drawings

FIG. 1 is a schematic overall structure diagram of the first embodiment;

FIG. 2 is a schematic view showing the structure of an incubator in accordance with one embodiment;

FIG. 3 is a schematic diagram of a surface treating element according to one embodiment;

FIG. 4 is a schematic structural view of a hot water tank according to a first embodiment;

FIG. 5 is an enlarged schematic view of portion A of FIG. 4;

FIG. 6 is a schematic view showing the structure in which the first guide roller is connected to the hot water tank in the first embodiment;

FIG. 7 is an enlarged schematic view of portion B of FIG. 6;

FIG. 8 is a schematic structural diagram of a support assembly according to one embodiment;

FIG. 9 is a schematic view showing a structure in which a first surface treatment tank and a second surface treatment tank are connected in the first embodiment;

FIG. 10 is a schematic flow chart of the second embodiment;

fig. 11 is a graph showing the effect of capillary migration of NC membranes in example 1 and comparative example 3 in example two.

Description of reference numerals: 1. coating the molding assembly; 11. a thermostat; 12. a steel belt; 2. a surface treatment assembly; 21. a hot water tank; 211. a first tension roller; 212. a first fixed block; 213. a first support plate; 214. a first guide roller; 215. a second guide roller; 216. a drain outlet; 217. a second fixed block; 218. a second support plate; 22. a circulation tank; 221. water permeable holes; 23. a first surface treatment tank; 231. a third guide roller; 232. a fourth guide roller; 233. a fifth guide roller; 234. a first guide roller; 235. a first mounting block; 236. a first liquid outlet; 24. a second surface treatment tank; 241. a second guide roller; 242. a second mounting block; 243. a second liquid outlet; 25. a partition plate; 3. a drying assembly; 4. a winding component; 5. a support assembly; 51. a support bar; 52. a connecting rod; 61. a water pump; 62. a water pumping pipe; 63. and a water supply pipe.

Detailed Description

The present application is described in further detail below with reference to figures 1-11.

The application discloses a production device and a process of a nitrocellulose membrane.

The first embodiment is as follows:

referring to fig. 1 and 2, the production equipment of the nitrocellulose membrane comprises a rack, and a coating forming component 1, a surface treatment component 2, a drying component 3 and a winding component 4 are sequentially arranged on the rack. Coating shaping subassembly 1 includes steel band 12 and thermostated container 11, and the 12 upper surfaces of steel band of uniform motion are injected into to the cellulose nitrate membrane oar through the peristaltic pump, and the steel band 12 of motion drives the cellulose nitrate membrane oar and removes towards 11 directions of thermostated container, and the thermostated container 11 of stage formula intensification removes solvent in the membrane oar, forms the cellulose nitrate membrane, realizes the coating shaping of cellulose nitrate membrane. The coat-formed nitrocellulose film is then conveyed to the surface treatment module 2.

Referring to fig. 1, the nitrocellulose membrane treated by the surface treatment assembly 2 continuously moves toward the drying assembly 3, and then the prepared nitrocellulose membrane is wound up by the winding assembly 4.

Referring to fig. 3, the surface treatment module 2 includes a hot water tank 21, a first surface treatment tank 23, and a second surface treatment tank 24 connected in this order, the hot water tank 21, the first surface treatment tank 23, and the second surface treatment tank 24 being disposed independently of each other, the first surface treatment tank 23 and the second surface treatment tank 24 being closely adjacent to each other and separated by a partition plate 25, and the hot water tank 21 being disposed between the incubator 11 and the first surface treatment tank 23.

Referring to fig. 4, the bottom of the hot water tank 21 is provided with a drainage outlet 216, the inner wall of the bottom of the hot water tank 21 is inclined, the drainage outlet 216 is located at the lower end of the bottom of the hot water tank 21, and after a period of use, the hot water in the hot water tank 21 is drained through the drainage outlet 216, so that the hot water can be replaced by new hot water.

Referring to fig. 4 and 5, a first stretching roller 211 is provided near the bottom of the hot water tank 21, a gap for the nitrocellulose membrane to pass through is left between the first stretching roller 211 and the bottom of the hot water tank 21, and the length direction of the first stretching roller 211 is perpendicular to the moving direction of the nitrocellulose membrane. The first fixing block 212 and the second fixing block 217 are welded on the inner wall of the hot water tank 21, the first fixing block 212 and the second fixing block 217 are respectively located on two inner walls, far away from each other, of the hot water tank 21, and two ends of the first tensioning roller 211 are respectively fixed on the first fixing block 212 and the second fixing block 217 through bolts. The bottom of the tank close to the hot water tank 21 is provided with two parallel first tensioning rollers 211 so that the nitrocellulose membrane is better immersed in the treatment liquid.

Referring to fig. 6 and 7, the upper end of the hot water tank 21 is provided with a first guide roller 214 and a second guide roller 215, the central axis of the first guide roller 214 is parallel to the central axis of the first tensioning roller 211, the first guide roller 214 and the second guide roller 215 are both positioned at the upper end of the hot water tank 21 and are arranged at the upper ends of two side plates which are far away from each other of the hot water tank 21, and the second guide roller 215 is arranged close to the first surface treatment tank 23.

The hot water tank 21 upper end is connected with support piece, and support piece includes first backup pad 213 and second backup pad 218, and first backup pad 213 and second backup pad 218 are located the both sides board that hot water tank 21 kept away from each other respectively, and first backup pad 213 and second backup pad 218 structure are the same and are "L" shape structure, and the equal fixed welding of first backup pad 213 and second backup pad 218 one end is on hot water tank 21, and the other end of first backup pad 213 and second backup pad 218 is all through bolted connection at the tip of first guide roll 214. Two groups of supporting pieces are arranged on the hot water tank 21, and the other group of supporting pieces are respectively connected to two ends of the second guide roller 215 through bolts, so that the second guide roller 215 is fixed.

Referring to fig. 3 and 6, the cellulose nitrate film passes above the first guide roller 214 and sequentially passes below the two first tensioning rollers 211, and then passes above the second guide roller 215 to extend toward the first surface treatment tank 23, completing the hot water treatment of the cellulose nitrate film.

Referring to fig. 6, a circulation tank 22 is provided between the hot water tank 21 and the first surface treatment tank 23, a partition is provided between the circulation tank 22 and the hot water tank 21, rectangular water permeable holes 221 are provided in the partition, and the circulation tank 22 and the hot water tank 21 are communicated with each other through the water permeable holes 221. The lowest position of the water permeable holes 221 is located at a position more than two thirds of the depth of the hot water tank 21, so that the nitrocellulose membrane can be better immersed in the hot water treatment. A heater for heating purified water is provided in the circulation tank 22, and hot water in the circulation tank 22 flows into the hot water tank 21 through the water permeable holes 221, so that the hot water in the hot water tank 21 is kept at a constant temperature, and a stable hot water source is provided for the hot water tank 21.

Referring to fig. 6, a communication member is further connected between the circulation tank 22 and the hot water tank 21, the communication member includes a water pump 61, a water pumping pipe 62 and a water supply pipe 63, one end of the water pumping pipe 62 is connected to the water pump 61, and the other end of the water pumping pipe 62 extends into the hot water tank 21 along the inner wall of the hot water tank 21. The water pump 61 is arranged at one side outside the hot water tank 21, one end of the water supply pipe 63 is connected to the water pump 61, and the other end of the water supply pipe 63 circulates in the tank 22. In this embodiment, the pumping pipe 62 and the water supply pipe 63 are made of hard plastic pipes, and are durable. The water pump 61 is started, the water pump 61 continuously pumps the hot water in the hot water tank 21, the hot water in the hot water tank 21 is conveyed into the circulation tank 22, the water level in the hot water tank 21 is lowered, the water level in the circulation tank 22 is raised, the hot water in the circulation tank 22 flows to the hot water tank 21 through the water permeable holes 221, and therefore the constant water temperature in the hot water tank 21 is achieved through circulation.

Referring to fig. 8, a filter cloth (not shown in the figure) is disposed at the water permeable hole 221, a support assembly 5 for fixing the filter cloth is disposed on the hot water tank 21, the support assembly 5 includes a support rod 51 and two connecting rods 52 connected to the end of the support rod 51, one ends of the two connecting rods 52 are fixed to the inner wall of the hot water tank 21, and the two connecting rods 52 and the support rod 51 form a U-shaped structure with an upward opening. The both ends of the vertical direction of filter cloth are fixed in its be close to connecting rod 52 respectively on, and the filter cloth is close to the tip of bracing piece 51 and fixes on bracing piece 51, adopts in this embodiment to bind fixed mode, makes filter cloth be expanded fixedly through supporting component 5, reduces in the circulation groove 22 impurity inflow hot water tank 21.

Referring to fig. 9, a first liquid outlet 236 is disposed at the bottom of the first surface treatment tank 23, a second liquid outlet 243 is disposed at the bottom of the second surface treatment tank 24, the bottoms of the first surface treatment tank 23 and the second surface treatment tank 24 are both inclined, the first liquid outlet 236 is located at the lower end of the bottom of the first surface treatment tank 23, and the second liquid outlet 243 is located at the lower end of the bottom of the second surface treatment tank 24. The second surface treatment bath 24 has the same structure as the first surface treatment bath 23.

Referring to fig. 9, a first guide roller 234 and two first mounting blocks 235 are disposed near the bottom of the first surface treatment tank 23, a gap is left between the first guide roller 234 and the bottom of the first surface treatment tank 23, and the shape and structure of the first mounting blocks 235 are the same as those of the first fixing block 212. One end of the first installation block 235 is connected with one end of the first guide roller 234 through a bolt, the other end of the first installation block 235 is welded on the inner wall of the first surface treatment tank 23, the two first installation blocks 235 are respectively positioned on two tank walls, far away from the first surface treatment tank 23, the length direction of the first guide roller 234 is vertical to the moving direction of the nitrocellulose membrane, the two first guide rollers 234 are arranged in the first surface treatment tank 23, and a gap is reserved between the two first guide rollers 234, so that the nitrocellulose membrane can be completely immersed in treatment liquid, and the nitrocellulose membrane can be better treated.

Referring to fig. 9, similarly, two second guide rollers 241 and four second mounting blocks 242 are provided near the bottom of the second surface treatment tank 24, the central axes of the second guide rollers 241 are parallel to the central axis of the first guide roller 234 and are located at the same level, and a gap for the cellulose nitrate film to pass through is left between the bottom of the second surface treatment tank 24 and the second guide rollers 241. The second mounting block 242 has the same shape and structure as the first mounting block 235. The second mounting block 242 is coupled to the second guide roller 241 in the same manner as the first mounting block 235 is coupled to the first guide roller 234.

Referring to fig. 9, a third guide roller 231 is disposed near an upper end edge of the first surface treatment tank 23, the third guide roller 231 is disposed at an end of the first surface treatment tank 23 far from the second surface treatment tank 24, and both ends of the third guide roller 231 are fixed at an upper end of the first surface treatment tank 23. A fourth guide roller 232 is provided at the upper end of the partition plate 25 between the first surface treatment tank 23 and the second surface treatment tank 24. A fifth guide roller 233 is provided above the side plate of the second surface treatment tank 24 away from the first surface treatment tank 23. While passing through the first surface treatment tank 23 and the second surface treatment tank 24 in this order, the nitrocellulose membrane also passes through the third guide roller 231, the fourth guide roller 232, and the fifth guide roller 233, which serve as guides, in this order.

In the present embodiment, the third guide roller 231, the fourth guide roller 232, and the fifth guide roller 233 are connected to the first surface treatment tank 23 and the second surface treatment tank 24 by the supporters. The third guide roller 231 has a center axis parallel to the center axis of the first guide roller 234, and the third guide roller 231, the fourth guide roller 232, and the fifth guide roller 233 are parallel to each other and located at the same height.

Referring to fig. 9, the nitrocellulose membrane is tensioned sequentially above the third guide roller 231, below the two first guide rollers 234, above the fourth guide roller 232, below the two second guide rollers 241, and above the fifth guide roller 233, so that the nitrocellulose membrane sequentially passes through the first surface treatment tank 23 and the second surface treatment tank 24. When the treatment liquid in the first surface treatment tank 23 needs to be replaced, the newly configured treatment liquid is added to the second surface treatment tank 24, the nitrocellulose membrane sequentially passes through the treatment liquids in the first surface treatment tank 23 and the second surface treatment tank 24, and at this time, the treatment liquid in the first surface treatment tank 23 is drained, so that the treatment liquid in the first surface treatment tank 23 is replaced. When the treatment liquid in the second surface treatment tank 24 needs to be replaced, the above method is also employed so that the nitrocellulose membrane is continuously immersed in the treatment liquid.

The implementation principle of the first embodiment is as follows: a hot water tank 21, a first surface treatment tank 23 and a second surface treatment tank 24 are sequentially arranged between the incubator 11 and the drying assembly 3, after the nitrocellulose membrane passes through the incubator 11, the circulating tank 22 is communicated with the hot water tank 21 through a water permeable hole 221, and hot water in the circulating tank 22 keeps the temperature of the hot water in the circulating tank 22 constant through a heater, so that the nitrocellulose membrane treatment is always kept in a constant temperature treatment condition; the arrangement of the first surface treatment groove 23 and the second surface treatment groove 24 is convenient for better replacing the treatment liquid during the production of the nitrocellulose membrane, the problem that the treatment liquid is replaced in a mode of stopping the machine or only replacing part of the treatment liquid is solved, the treatment liquid in the first surface treatment groove 23 and the second surface treatment groove 24 can be thoroughly replaced, the intermittent alternate replacement and use of the first surface treatment groove 23 and the second surface treatment groove 24 are realized, impurities in the treatment liquid acting on the nitrocellulose membrane are reduced, and the quality of the nitrocellulose membrane is improved.

Example two:

the second embodiment discloses a production process of a nitrocellulose membrane.

PBS treatment solution: 81ml of 5mM disodium hydrogenphosphate, 19ml of 5mM sodium dihydrogenphosphate and 0.9g of sodium chloride.

The prepared NC film is subjected to appearance inspection by adopting a lamp inspection mode, and the inspection is mainly performed under a backlight lamp.

Capillary migration test of NC films: adding water into the container, marking one end of the NC film, bonding the marked end of the NC film on the bracket, extending one end of the NC film far away from the mark into the water in the container, and beginning to adsorb the water in the container by the NC film for timing.

The NC membrane antibody scribing adopts a membrane scribing metal spraying instrument produced by Shanghai Jiening biotechnology limited.

Protein adsorption experiments: the lateral chromatography technology is adopted, an NC membrane is taken as a carrier, a specific antigen or antibody is fixed on the NC membrane, when a sample to be detected is dripped on a sample pad at one end of a test strip, the sample moves laterally through capillary action, and generates specific immunoreaction with a reagent marked by colloidal gold or microspheres on a combination pad, and then the sample moves on the NC membrane, is captured by the antigen or antibody fixed on the surface of the NC membrane and is gathered on a detection belt, and a visual color development result is obtained by visually observing the density of a light reflection signal of a marker (colloidal gold or latex particles) on the surface of the cellulose nitrate.

And (3) an observation method: when preparing the NC membrane slurry, a small amount of samples are taken from a sampling port after full stirring to observe the condition of solid matters (namely undissolved particles exist), and the membrane slurry is prepared when no particles exist; if the solid matter still exists in the membrane pulp, the undissolved nitrocotton is still contained, the sample is continuously stirred, after stirring for 20-30 minutes, whether the content of the undissolved solid matter changes or not is observed again, and the membrane pulp dissolution is finished if the content of the undissolved solid matter does not change.

The hot water used in this application is hot purified water.

Example 1

Referring to fig. 10 and 11, the NC film is produced as follows:

(1) preparing an NC membrane paddle: weighing 100L of acetone, pouring into a liquid preparation tank, adding 25kg of nitrocotton, starting a stirrer to stir for 3 hours at 65r/min, adding 45L of ethanol, 40L of n-butanol and 5L of glycerol, and continuously stirring for 3 days. Observing the condition of solid matters in the stirred sample to complete the dissolution of the NC membrane paddle;

(2) filtering NC membrane slurry: adopting an oil-proof Polytetrafluoroethylene (PTFE) filtering membrane paddle, and standing for 3 days;

(3) coating and forming by NC film and film slurry: the PE film is tightly attached to the stainless steel, the NC film slurry solution is injected onto the PE film, and the NC film slurry solution runs on the stainless steel belt at a constant speed along with the PE film;

the membrane pulp solution of the NC membrane sequentially passes through a constant temperature box with the length of 15m, the temperature of 20 ℃, 22 ℃, 26 ℃, 32 ℃ and 36 ℃ along with the PE membrane, wherein the humidity of air is 50%, and the running speed of a stainless steel belt is 8.83 m/h;

(4) and (3) surface treatment of an NC film: a step of hot water treatment in which the NC film is slid into a hot water tank 21 having a water temperature of 63 ℃, two thirds of the hot water in the hot water tank 21 is replaced with fresh pure water every 24 hours, the NC film is treated in the hot water tank 21 for 5 minutes, and the NC film is slid into PBS treatment liquid after passing through the hot water tank 21;

and (3) treating with the PBS, wherein the NC membrane passes through the first surface treatment tank 23 and the second surface treatment tank 24 in sequence, passes through the PBS in the first surface treatment tank 23, and does not contain the PBS in the second surface treatment tank 24. Wherein the pH value of the PBS treatment solution is 7.4; every 3 hours, the pH of the PBS treatment solution in the first surface treatment tank 23 was measured so that the pH was maintained at 7.0 to 7.5, and the amount of the new PBS treatment solution added was determined based on the solute in the PBS treatment solution adsorbed by the NC membrane during 3 hours so that the solute in the PBS treatment solution in the first surface treatment tank 23 was kept constant.

When the first surface treatment tank 23 is replaced with a new PBS treatment liquid, the newly configured PBS treatment liquid is added to the second surface treatment tank 24, the PBS treatment liquid in the first surface treatment tank 23 is drained, the tank body of the first surface treatment tank 23 is cleaned and sterilized, and the PBS treatment liquid in the second surface treatment tank 24 is used for treating the NC film surface, so that the replacement of the PBS treatment liquid in the first surface treatment tank 23 or the second surface treatment tank 24 is completed in a circulating manner.

(5) The NC film was dried in an oven at 45 ℃ and wound up.

Example 2

The difference between the embodiment 2 and the embodiment 1 is that 110L of acetone is measured in the step (1) and poured into a liquid preparation tank, 25kg of nitrocotton is added, a stirrer is started for 65r/min and stirred for 3 hours, and then 40L of ethanol, 50L of n-butanol and 6L of glycerol are added and stirred continuously for 3 days. Observing the condition of solid matters in the stirred sample to complete the dissolution of the membrane paddle;

in the step (3), the humidity of the air is 65%;

in the step (4), the temperature of the water for the NC membrane hot water treatment is 60 ℃.

Example 3

The difference between the embodiment 3 and the embodiment 1 is that 90L of acetone is measured in the step (1) and poured into a liquid preparation tank, 27kg of nitrocotton is added, a stirrer is started for 65r/min and stirred for 3 hours, and then 50L of ethanol, 40L of n-butanol and 6L of glycerol are added and stirred continuously for 3 days. Observing the condition of solid matters in the stirred sample to complete the dissolution of the membrane paddle;

in the step (4), the water temperature for the NC membrane hot water treatment is 66 ℃.

Example 4

The difference between the embodiment 4 and the embodiment 1 is that 100L of acetone is measured in the step (1) and poured into a liquid preparation tank, 22kg of nitrocotton is added, a stirrer is started for 65r/min and stirred for 3 hours, and then 45L of ethanol, 40L of n-butanol and 6L of glycerol are added and stirred continuously for 3 days. Observing the condition of solid matters in the stirred sample to complete the dissolution of the membrane paddle;

in step (3), the humidity of the air is 40%.

Example 5

The difference between the embodiment 5 and the embodiment 1 is that 110L of acetone is measured in the step (1) and poured into a liquid preparation tank, 25kg of nitrocotton is added, a stirrer is started for 65r/min and stirred for 3 hours, and then 40L of ethanol, 50L of n-butanol and 10L of glycerol are added and stirred continuously for 3 days. Observing the condition of solid matters in the stirred sample to complete the dissolution of the membrane paddle;

Comparative example 1

Comparative example 1 is different from example 1 in that the solvent acetone was added in an amount of 150L, and other conditions were the same as in example 1.

Comparative example 2

Comparative example 2 is different from example 1 in that the solvent acetone was added in an amount of 80L, and other conditions were the same as in example 1.

Comparative example 3

Comparative example 3 is different from example 1 in that the temperature of water during the hot water treatment of step (4) is set to normal temperature, and other conditions are the same as example 1.

TABLE 1 comparison of the process step conditions and the results of the products under NC film lamp inspection in examples 1 to 5 and comparative examples 1 to 3

From the process conditions and NC film results in table 1, the process conditions of examples 1-5 all meet the quality requirements for NC production.

In the examples 1-3, the content of acetone in different solvents is tested, and the NC film which has a smooth surface, no defects, dampness, mildew and the like, is smooth in surface, has no bubbles, wiredrawing, black spots and light reflection and meets the production requirements is prepared by the acetone within the range of 90-110L. Among them, the type a + NC film was obtained in the production methods of examples 1 to 3, and the quality of the NC film was high.

Meanwhile, in the examples 1-3, the water temperature of hot water treatment in the NC membrane surface treatment is changed, and the prepared NC membrane meets the production quality requirement within the range of 60-66 ℃.

Examples 2 to 4 changed and adjusted the relative humidity of air in the coating and forming process of the NC film, and the NC film prepared in the range of the relative humidity of air of 40% to 65% all satisfied the production quality requirement, and the preparation method of example 4 was adopted to prepare the type B NC film, and the quality of the NC film was better.

Compared with the example 1, the content of the raw materials in the NC membrane pulp is changed in the example 5, the NC prepared under the condition also meets the production requirement, and the type-A NC membrane can be prepared by adopting the preparation mode of the example 5.

Comparative example 1 compared with example 1, comparative example 1 increased the amount of acetone added, the acetone content reached 150L during the preparation of NC film membrane slurry, and the solvent acetone content was too high during the preparation of NC film. After coating and forming, the content of acetone remained in the NC film is high, the surface of the NC film has a reflection phenomenon, and the production requirement is not met.

The amount of acetone added in comparative example 2 was 80L, and the amount of acetone added in comparative example 2 was reduced compared to that in example 1, and it was found that the NC film produced a laminate and did not meet the quality requirements for NC film production.

Comparative example 3 compared to example 1, only the hot water at 63 ℃ in the hot water treatment was replaced by the normal temperature water, under the condition, the prepared NC film still contains a small amount of impurities on the surface, the quality of the NC film is affected, and it is found that bacteria are generated in the water tank when the normal temperature water treatment is used for a period of time, and the water tank needs to be cleaned and cleaned in time for many times.

In order to further investigate the factors affecting the quality of the NC film and the influence of impurities on the capillary migration effect of the NC film, the NC films prepared in example 1 and comparative example 3 were selected for the test of the capillary migration effect. Referring to fig. 11, the NC film prepared in comparative example 3 is the NC film numbered 1 in fig. 11, and is prepared at normal temperature; the NC film prepared in example 1 is the NC film designated as 2 in fig. 11, and is prepared by being subjected to hot water treatment. FIG. 11A is a schematic view of the state before the adsorption of the NC membrane, and FIG. 11B is a schematic view of the state after the adsorption of the NC membrane, under the same conditions and time conditions, the running time of water on the NC membrane of reference numeral 2 is faster; because the NC membrane of the label 1 has impurities, the liquid level of water is inclined or not absorbed in a horizontal mode when the NC membrane of the label 1 runs, the application of the NC membrane is influenced, and the production requirement is not met.

Comparative example 4

Comparative example 4 is different from example 1 in that, in step (4), the NC film passes through only the first surface treatment bath 23 or the second surface treatment bath 24. In the production exemplified by the first surface treatment bath 23, in the step (4), the NC film passed through only the first surface treatment bath 23, and the NC film passed through the PBS treatment solution in the first surface treatment bath 23, the pH of the PBS treatment solution being 7.4.

When the PBS treatment liquid is replaced in the first surface treatment tank 23 by 24 hours, two thirds of the volume of the PBS treatment liquid in the first surface treatment tank 23 is discharged, and then the volume of the PBS treatment liquid in the first surface treatment tank 23 is added to the tank in the same volume as the volume of the discharged PBS treatment liquid, so that the volume of the PBS treatment liquid in the first surface treatment tank 23 is kept constant, thereby completing the replacement of the PBS treatment liquid in the first surface treatment tank 23. In the process, the process of replacing the PBS treatment liquid is complicated, and in the process, impurities contained in the PBS treatment liquid in the first surface treatment tank 23 are difficult to completely remove, and the impurities can breed some microorganisms, so that the quality of the NC membrane is influenced in subsequent use.

In addition, in the application, in the process of coating and forming the NC film, a stage-type constant temperature rise mode is adopted, and when the temperature is set to be higher than 40 ℃, the prepared NC film has more bubbles, so that the limitation of production on the bubble content cannot be met, the quality of the NC film is influenced, and the production requirement cannot be met.

In the hot water treatment test process, the test is carried out by adopting the water temperature of more than 66 ℃, and when the water temperature of the hot water is higher than 66 ℃, the impurities of the NC membrane can be washed away, so that the PBS treatment liquid components required by the surface of the subsequent treatment membrane are protected. However, in actual production requirements, when the temperature is high, hot water volatilizes quickly, the volatilization of the hot water can affect the air humidity for producing the NC membrane, a large amount of electric energy is consumed, the production cost is improved, and the temperature condition of more than 66 ℃ is not adopted from the production perspective.

Application example 1

In order to measure the quality of the NC film prepared in example 1, the NC film prepared in example 1 was selected and subjected to capillary migration, antibody streaking effect, and protein adsorption experiment.

Table 2 application test experiment of NC film in example 1

In table 2, the capillary migration speed and the appearance test both meet the production requirements, the NC membrane in example 1 has fewer impurities, and the antibody streaking effect and the protein adsorption experiment effect are both excellent, and the production process for preparing the NC membrane in example 1 can be popularized and applied in a large scale, and has a good application prospect.

In actual production, NC films prepared by the production process of the present application have been put on the market, and the prepared NC films are classified as follows according to the quality of the NC films:

class A + is: the thickness of the coating layer with the backing is 0.115-0.175mm except the backing; the error of the same plate is less than or equal to 0.01 mm; the error of the same volume number is less than or equal to 0.02 mm; the error of the same batch is less than or equal to 0.03 mm; the sum of other poor quality is not more than 1%;

a type: the thickness of the coating layer with the backing is 0.115-0.175mm except the backing; the error of the same plate is less than or equal to 0.02 mm; the error of the same number is less than or equal to 0.03 mm; the error of the same batch is less than or equal to 0.04 mm; the sum of other poor quality is not more than 5%;

b type: the thickness of the coating layer except the backing layer with the backing layer ranges from 0.105 mm to 0.175 mm; the error of the same plate is less than or equal to 0.02mm, and the error of the same coil number is less than or equal to 0.04 mm; the error of the same batch is less than or equal to 0.05 mm.

In the production process, the hot water treatment of the NC film is added, the first surface treatment groove 23 or the second surface treatment groove 24 which is convenient for replacing PBS treatment liquid is arranged, the impurities of the PBS treatment liquid in the first surface treatment groove 23 or the second surface treatment groove 24 are reduced, and the yield of products is greatly improved.

The present embodiment is only for explaining the present application, and it is not limited to the present application, and those skilled in the art can make modifications of the present embodiment without inventive contribution as needed after reading the present specification, but all of them are protected by patent law within the scope of the claims of the present application.

Claims

1. The utility model provides a production facility of nitrocellulose membrane, characterized in that, is including being used for surface treatment subassembly (2) of nitrocellulose membrane surface treatment, and surface treatment subassembly (2) are including first surface treatment groove (23) and second surface treatment groove (24) that mutually independent and adjacent set up, and the tank bottom of first surface treatment groove (23) is equipped with first liquid outlet (236), and the tank bottom of second surface treatment groove (24) is equipped with second liquid outlet (243).

2. The apparatus for producing a nitrocellulose membrane according to claim 1, wherein the bottom of the first surface treatment tank (23) is disposed obliquely, the first liquid outlet (236) is located at a lower end of the bottom of the first surface treatment tank (23), a first guide roller (234) is disposed near the bottom of the first surface treatment tank (23), the second surface treatment tank (24) has the same structure as the first surface treatment tank (23), a second guide roller (241) is disposed near the bottom of the second surface treatment tank (24), and gaps are left between the first guide roller (234) and the bottom of the first surface treatment tank (23) and between the second guide roller (241) and the bottom of the second surface treatment tank (24).

3. The nitrocellulose membrane production apparatus of claim 1, wherein the surface treatment assembly (2) further comprises a hot water tank (21), the hot water tank (21) is located on one side of the first surface treatment tank (23) away from the second surface treatment tank (24), a circulation tank (22) is arranged on one side of the hot water tank (21), a partition plate is arranged between the circulation tank (22) and the hot water tank (21), a water permeable hole (221) is formed in the partition plate, and a filter cloth is arranged at the water permeable hole (221).

4. A nitrocellulose membrane production apparatus according to claim 3, wherein the hot water tank (21) is provided with a support assembly (5) near the water permeable hole (221) for supporting the filter cloth, the support assembly (5) comprises a support rod (51) and a connecting rod (52) connected to the end of the support rod (51), two ends of the filter cloth are respectively fixedly connected with the corresponding connecting rod (52), and the end of the filter cloth near the support rod (51) is fixed on the support rod (51).

5. The nitrocellulose membrane production equipment of claim 3, wherein a communication piece is further connected between the hot water tank (21) and the circulation tank (22), the communication piece comprises a water pump (61), a water pumping pipe (62) and a water supply pipe (63), one end of the water pumping pipe (62) extends into the lower end of the inner wall of the hot water tank (21), and the other end of the water pumping pipe (62) is connected to the water pump (61); one end of the water supply pipe (63) is connected with the water pump (61), and the other end of the water supply pipe is communicated with the circulating groove (22).

6. The apparatus for producing a nitrocellulose membrane of claim 3, wherein the water permeable hole (221) is provided at a position more than two thirds of the depth of the hot water tank (21).

7. A process for producing a nitrocellulose membrane, characterized by surface-treating a nitrocellulose membrane with the apparatus for producing a nitrocellulose membrane of any one of claims 1 to 6, comprising the steps of:

coating and forming a cellulose nitrate membrane film paddle;

the coating-formed nitrocellulose membrane (NC membrane) sequentially passes through a hot water tank (21), a first surface treatment tank (23) and a second surface treatment tank (24);

wherein the PBS treatment liquid is added into the first surface treatment groove (23) or the second surface treatment groove (24); the time of the NC film passing through the hot water tank (21) is more than 1 min.

8. The process for producing a nitrocellulose membrane of claim 7, wherein the temperature of the hot water treatment is 60 ℃ to 66 ℃.

9. The process for producing a nitrocellulose membrane according to claim 7, wherein a staged baking manner is adopted in the coating and forming process of the nitrocellulose membrane paddle, the nitrocellulose membrane sequentially passes through different temperature stages, the temperature is raised from 19-21 ℃ to 34-36 ℃, and the relative humidity of air is 40% -65%.