A method and system for continuously producing hydrophobic film on the surface of gypsum board

Abstract

The invention discloses a method for continuously producing a hydrophobic film on the surface of a paper-faced gypsum board, comprising the following steps: putting methyl hydrogenated silicone oil into a potassium hydroxide solution to obtain a silicone oil alkaline solution A; adding the silicone oil alkaline solution A to stirring water to obtain a silicone oil alkaline solution B; applying the silicone oil alkaline solution B evenly to a wet plate by a roller coating device, performing high-temperature film formation, and hydrolyzing the remaining Si-H groups in the silicone oil alkaline solution B with the water vapor generated by the wet plate at high temperature to obtain a dry plate and a surface hydrophobic film fixed on the dry plate; and a system for continuously producing a method for continuously producing a hydrophobic film on the surface of a paper-faced gypsum board. The invention realizes the continuous roller coating of the lower face paper of the wet plate during the wet plate conveying process, and the time cost is reduced. At the same time, the surface hydrophobic film roller-coated on the gypsum board can consume steam without affecting the circulation of steam, reduce the accumulation of steam, and improve the connection effect between the lower face paper and the gypsum board core.

Description

Technical Field

[0001] The invention relates to the field of gypsum board production, and in particular to a continuous production method and system for a hydrophobic film on the surface of a paper-faced gypsum board. Background Art

[0002] Gypsum board is a common building material with extremely high application value. However, when using it, people find that the core material of the gypsum board has the characteristic of easy moisture absorption. It is easy to absorb water, mold, or even crack in a humid environment, resulting in a decrease in its durability. Therefore, how to improve its durability and reduce its water absorption rate has become a problem.

[0003] The most common type of gypsum board on the market today is paper-faced gypsum board, whose main components are gypsum, facing paper and some additives. In order to reduce its water absorption rate, people often consider adding hydrophobic materials during the preparation of the gypsum board core to prevent the gypsum board core from absorbing water. However, since the facing paper also has the property of easy moisture absorption and its surface is hydrophilic, moisture will penetrate through the paper surface into the gypsum core layer. Over time, it will still penetrate into the board core, destroying the bond between the paper surface and the gypsum, destroying the connection between the gypsum molecules, and affecting normal use.

[0004] In order to prevent the face paper from getting damp and moldy, and to prevent water from penetrating into the board core from the face paper, the face paper can now be laminated to improve the waterproof performance of the gypsum board. However, in the actual operation, there are two defects when pre-coating the waterproof film on the face paper: 1. Pre-laminating the face paper will extend the preparation process line of the gypsum board, resulting in a longer production time of the gypsum board and a significant increase in the preparation cost; 2. Since the face paper has a hydrophobic property, when the wet board is dried, when water vapor rises from the board core to the face paper, it is not easy for the water vapor to flow out of the face paper. The steam is easily separated from the board core and the face paper during the continuous squeezing process, resulting in bulging, which in turn reduces the performance of the gypsum board. Summary of the invention

[0005] The object of the present invention is to provide a continuous production method and system for a hydrophobic film on the surface of a gypsum board, so as to solve the technical problems in the prior art of extending the production line and making it difficult to discharge water vapor when coating the surface of the gypsum board with a hydrophobic film.

[0006] In order to solve the above technical problems, the present invention specifically provides the following technical solutions:

[0007] The present invention provides a method for continuously producing a hydrophobic film on the surface of a gypsum board, comprising the following steps:

[0008] Dissolve potassium hydroxide in solvent water to obtain a potassium hydroxide solution with a mass fraction of 20%;

[0009] Putting methyl hydrogenated silicone oil into the potassium hydroxide solution for the first hydrolysis, stirring evenly, to obtain silicone oil alkaline solution A, wherein the silicone oil alkaline solution A contains Si-H groups;

[0010] The silicone oil alkaline solution A is added to the stirred water for a second hydrolysis, whereby part of the Si-H groups in the silicone oil alkaline solution A are hydrolyzed into Si-OH groups, and the solution is stirred evenly to obtain a silicone oil alkaline solution B;

[0011] The silicone oil alkaline solution B is evenly applied to the wet plate by a roller coating device to form a film at high temperature, and the remaining Si-H groups in the silicone oil alkaline solution B and the water vapor generated by the wet plate at high temperature are hydrolyzed for the third time to obtain a dry plate and a surface hydrophobic film fixed on the dry plate;

[0012] Part of the Si-OH groups hydrolyzed for the third time can combine with the face paper fibers on the wet plate, and the remaining Si-OH groups form a stable -Si-O- covalent network through self-condensation to cover the surface of the dry plate, thereby achieving the fixation of the surface hydrophobic film on the dry plate.

[0013] As a preferred embodiment of the present invention, the silicone oil alkaline solution B is roller-coated onto the surface of the lower face paper of the wet plate.

[0014] As a preferred solution of the present invention, during the high-temperature film forming process, the remaining water vapor overflows from the bottom of the wet plate until the wet plate forms the dry plate.

[0015] As a preferred embodiment of the present invention, the wet board is an undried gypsum board.

[0016] As a preferred embodiment of the present invention, in the first hydrolysis process, the ratio of the potassium hydroxide solution to the methyl hydrogen silicone oil is 1:5 by weight;

[0017] During the second hydrolysis process, the ratio of the silicone oil alkaline solution A to the stirred water is 1:2.

[0018] The present invention also provides a system for a continuous production method of a hydrophobic film on the surface of a gypsum board, comprising:

[0019] A mixing device for continuously producing a silicone oil alkaline solution B and a conveying device for continuously conveying a wet plate, wherein the mixing device is connected to the conveying device via a roller coating device, the mixing device conveys the silicone oil alkaline solution B into the roller coating device, and the roller coating device rolls the silicone oil alkaline solution B onto the lower face paper of the wet plate on the conveying device;

[0020] A dryer is installed downstream of the conveying device, and the dryer is used to dry the wet plate after the silicone oil alkaline solution B is roller-coated, and the silicone oil alkaline solution B forms a film on the wet plate at a high temperature.

[0021] As a preferred solution of the present invention, it also includes a control component, which is communicatively connected with the mixing device, and the control component is used to control the mixing device to continuously discharge materials to the roller coating equipment.

[0022] As a preferred embodiment of the present invention, the mixing device is provided with a solid-liquid mixing bin for preparing a potassium hydroxide solution, a primary hydrolysis bin for preparing a silicone oil alkaline solution A, and a secondary hydrolysis bin for preparing the silicone oil alkaline solution B in sequence from top to bottom, the secondary hydrolysis bin is connected to the roller coating device, and the solid-liquid mixing bin, the primary hydrolysis bin, and the secondary hydrolysis bin are connected in sequence through an automatic feeding pipe;

[0023] The primary hydrolysis bin and the secondary hydrolysis bin are both externally connected with a feeding pipe, and the feeding pipe can add required materials to the solid-liquid mixing bin, the primary hydrolysis bin and the secondary hydrolysis bin at the same time. The solid-liquid mixing bin is provided with a quantitative feeding cylinder capable of passing quantitative materials into the solid-liquid mixing bin;

[0024] The automatic unloading pipe, the quantitative loading cylinder and the loading pipe are all connected to the control component.

[0025] As a preferred solution of the present invention, a liquid level sensor is provided in the secondary hydrolysis tank, and the liquid level sensor is communicatively connected with the control component;

[0026] When the solution height in the secondary hydrolysis tank is lower than the liquid level sensor, the liquid level sensor sends a loading signal to the control component, and the control component controls the quantitative loading cylinder and the loading pipe to perform a single loading, and the automatic unloading pipes from top to bottom open in sequence to realize a single feeding of the secondary hydrolysis tank.

[0027] As a preferred solution of the present invention, the roller coating device comprises a bracket installed on the conveying device, the bracket spans over the conveying device and can be suspended above the wet plate, a roughening roller is rotatably installed in the bracket through a bearing, a liquid outlet is connected to the top of the roughening roller, and the bottom of the roughening roller can be arranged in contact with the wet plate;

[0028] The liquid outlet is connected to the secondary hydrolysis chamber through a feed channel, a valve is provided in the feed channel, and the valve is communicatively connected to the control component;

[0029] A roller is arranged at the liquid outlet, and the outer wall of the roller is arranged in contact with the roughening roller. When the roughening roller is rolled, the roller can be driven to roll in the unloading channel and drive the silicone oil alkaline solution B to flow out from the liquid outlet. The silicone oil alkaline solution B is absorbed by the roughening roller and rolled onto the wet plate.

[0030] Compared with the prior art, the present invention has the following beneficial effects:

[0031] The present invention prepares a methyl hydrogen silicone oil waterproof film during the wet board forming process, realizes continuous roller coating of the lower face paper of the wet board during the wet board conveying process, and simultaneously obtains a dry board and a surface hydrophobic film fixed on the dry board by high-temperature drying after roller coating, thereby realizing a continuous coating process of the lower face paper during the production process, without the need to process the face paper in advance, ensuring the preparation time of the gypsum board, and without increasing the time cost;

[0032] After the methyl hydrogen silicone oil waterproof film is initially rolled onto the wet board, the wet board is sent to a dryer for high-temperature secondary coating. Under high temperature, the water vapor on the wet board reacts with the material first rolled to generate a surface hydrophobic film fixed on the gypsum board. The film can consume the steam without affecting the circulation of the steam, reduce the accumulation of the steam, and improve the connection effect between the lower face paper and the gypsum board core.

[0033] The present invention realizes continuous coating treatment of gypsum boards on a gypsum board production line by simultaneously carrying out a gypsum board production device and a waterproof film coating device, and crosses the two devices together through a simple roller coating device. The action structure is simple, process time is saved, and production costs are reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the implementation methods of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for the implementation methods or the description of the prior art. Obviously, the drawings in the following description are only exemplary, and for ordinary technicians in this field, other implementation drawings can be derived from the provided drawings without creative work.

[0035] Figure 1 The present invention provides a schematic flow chart of a continuous production method of a hydrophobic film on the surface of a gypsum board;

[0036] Figure 2 A schematic structural diagram of a system for providing a method for continuously producing a hydrophobic film on the surface of a gypsum board according to the present invention;

[0037] Figure 3 The present invention provides Figure 2 A schematic diagram of the internal structure of the mixing device in the illustrated embodiment;

[0038] Figure 4 The present invention provides Figure 2 A schematic diagram of the partial structure of the front side of the roller coating device in the embodiment shown;

[0039] Figure 5 The present invention provides Figure 2 A schematic diagram of the partial structure of the roller coating device in the illustrated embodiment.

[0040] The numbers in the figure represent the following:

[0041] 1- conveying device; 2- mixing device; 3- roller coating equipment; 4- dryer; 5- liquid level sensor; 6- wet plate;

[0042] 201-solid-liquid mixing chamber; 202-primary hydrolysis chamber; 203-secondary hydrolysis chamber; 204-automatic unloading pipe; 205-loading pipe; 206-quantitative loading cylinder; 207-stirring paddle;

[0043] 301- bracket; 302- bearing; 303- roughening roller; 304- liquid outlet; 305- material discharge channel; 306- valve; 307- roller. DETAILED DESCRIPTION

[0044] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0045] like Figure 1 As shown, the present invention provides a method for continuously producing a hydrophobic film on the surface of a gypsum board, comprising the following steps:

[0046] Dissolve potassium hydroxide in solvent water to obtain a potassium hydroxide solution with a mass fraction of 20%;

[0047] The methyl hydrogenated silicone oil is put into a potassium hydroxide solution for the first hydrolysis, and stirred evenly to obtain a silicone oil alkaline solution A, wherein the silicone oil alkaline solution A contains Si-H groups, and the potassium hydroxide solution mainly provides an alkaline environment for the silicone oil alkaline solution A;

[0048] Add silicone oil alkaline solution A to stirring water for a second hydrolysis. In an alkaline environment, Si-H groups can undergo hydrolysis reaction with water in the solution to generate hydrophobic groups Si-OH. Stir evenly to obtain silicone oil alkaline solution B. At this time, there are still some unhydrolyzed Si-H groups in silicone oil alkaline solution B.

[0049] The above steps are all carried out during the preparation of the wet board. When the preparation of the silicone oil alkaline solution B is completed, the wet board on the gypsum board production line is prepared at the same time;

[0050] The silicone oil alkaline solution B is evenly applied to the wet board by a roller coating device, and the wet board is sent to a gypsum board dryer for high-temperature film formation. The remaining Si-H groups in the silicone oil alkaline solution B and the water vapor generated by the wet board at high temperature undergo a third hydrolysis, and as the water vapor in the wet board completely overflows, a dry board and a surface hydrophobic film fixed on the dry board are obtained;

[0051] Part of the Si-OH groups hydrolyzed for the third time can combine with the paper fibers on the wet plate, and the remaining Si-OH groups self-condense to form a stable -Si-O- covalent network covering the surface of the dry plate, thereby achieving the fixation of the surface hydrophobic film on the dry plate.

[0052] A water drop test was conducted on the surface of the finished gypsum board coming out of the dryer. It can be seen that water droplets form water droplets on the surface of the gypsum board. The water droplets can roll on the surface, and no moisture is left on the paper surface after rolling.

[0053] After testing using the surface absorption test method, it can be seen that the surface water absorption has been significantly reduced.

[0054] In the above preparation method, the preparation and drying of the wet board belong to the original preparation process. On the basis of the original preparation process, its process parameters are not changed. However, during the transportation of the wet board, the waterproof material prepared at the same time is rolled onto the wet board of the gypsum board through a roller coating device, thereby realizing a continuous lamination process of the lower facing paper during the production process. There is no need to process the facing paper in advance, thereby ensuring the preparation time of the gypsum board and no increase in time cost.

[0055] After the methyl hydrogen silicone oil waterproof film is initially roll-coated onto the wet board, the wet board is sent to a dryer for high-temperature secondary coating. Under high temperature conditions, the water vapor on the wet board reacts with the material rolled for the first time to form a surface hydrophobic film fixed on the gypsum board, which does not affect the circulation of steam and can react with steam, reducing the accumulation of steam and improving the connection effect between the lower face paper and the gypsum board core.

[0056] Since the performance of gypsum board, such as supporting performance, is mainly provided by the lower face paper, the silicone oil alkaline solution B is rolled onto the surface of the lower face paper of the wet board. Only the methyl hydrogen silicone oil waterproof film is rolled onto the lower face paper, which can not only absorb the water vapor evaporated onto the lower face paper, making the lower face paper and the core of the gypsum board more closely connected, achieving a better supporting waterproof effect, but also simplifying the film coating process and reducing production costs.

[0057] As the drying process continues, the surface hydrophobic film is continuously formed on the gypsum board, and the subsequent water vapor is difficult to be discharged from the position of the lower protective paper. Therefore, during the high-temperature film forming process, the remaining water vapor overflows from the bottom of the wet board until the wet board becomes a dry board. Therefore, in the preparation process of the surface hydrophobic film, the waterproof film can be coated on the lower protective paper. Double-sided coating not only has a poor effect but is also not conducive to the outflow of water vapor.

[0058] The wet board shown in the present invention is an undried paper-faced gypsum board. The preparation and cutting of the wet board do not affect the continuous production of the surface hydrophobic film, so the steps of preparing and cutting the wet board are omitted in the present invention.

[0059] In the second hydrolysis process, it is necessary to ensure that the methyl hydrogen silicone oil contains Si-OH and unhydrolyzed Si-H. Therefore, the water content is important in the second hydrolysis process. In terms of weight ratio, in the first hydrolysis process, the potassium hydroxide solution: methyl hydrogen silicone oil is 1:5.

[0060] During the second hydrolysis process, the ratio of silicone oil alkaline solution A: stirring water was 1:2.

[0061] In order to distinguish the preparation of the alkaline solution and the second hydrolysis process, the water in the first preparation of the alkaline solution is called solvent water, and the water that reacts with the silicone oil alkaline solution A in the second hydrolysis process is called stirring water. However, solvent water and stirring water are both common water on the market, such as distilled water.

[0062] From the method steps of the present invention, it can be obtained that the surface hydrophobic film and the gypsum board are prepared and formed together, so it belongs to parallel production, and absorbs water vapor on the wet gypsum board during the parallel production process, which plays a beneficial role in the production of gypsum board. There are common equipment on the market for the production of gypsum board, but the present invention needs to further disclose how the production of the surface hydrophobic film is beneficially combined with the gypsum board production line to achieve continuous production and coating operations.

[0063] like Figures 2 to 5 As shown, the present invention further discloses a system for a continuous production method of a hydrophobic film on the surface of a gypsum board, comprising:

[0064] A mixing device 2 for continuously producing a silicone oil alkaline solution B and a conveying device 1 for continuously conveying a wet plate, the mixing device 2 is connected to the conveying device 1 via a roller coating device 3, the mixing device 2 conveys the silicone oil alkaline solution B into the roller coating device 3, and the roller coating device 3 roller-coats the silicone oil alkaline solution B onto the lower protective paper of the wet plate located on the conveying device 1.

[0065] A dryer 4 is installed downstream of the conveying device 1. The dryer 4 is used to dry the wet plate after the silicone oil alkaline solution B is roller-coated. At the same time, the silicone oil alkaline solution B forms a film on the wet plate at a high temperature.

[0066] During the preparation of the wet board, the mixing device 2 simultaneously completes the preparation of the silicone oil alkaline solution B. When the wet board enters the roller coating position, the roller coating device 3 is fed with the silicone oil alkaline solution B and completes the roller coating of the surface of the face paper on the wet board, and this action is continuous and uninterrupted. After the wet board is roller coated, it directly enters the dryer 4 for drying. At this time, the silicone oil alkaline solution B and the water vapor of the wet board core dried by the dryer at high temperature will not only make the unhydrolyzed Si-H and the water molecules evaporated from the board core continue to hydrolyze into Si-OH, but also a part of Si-OH is combined with the face paper fiber to fix the hydrophobic group to the surface of the gypsum board, and the other Si-OH forms a more stable -Si-O- covalent network through self-condensation to cover the surface of the gypsum board, and finally forms a hydrophobic film on the surface of the gypsum board. And a dry board can be obtained, and the surface hydrophobic film is directly fixed on the dry board, realizing the continuous production of the surface hydrophobic film of the paper-faced gypsum board.

[0067] In order to prevent the silicone oil alkaline solution B from being used up and requiring a material replacement operation, the production of the wet plate needs to be stopped, which will cause a large loss. Therefore, in this embodiment, a control component is also included, which can drive the mixing device 2 to perform full-automatic continuous production. The control component is connected to the mixing device 2 for communication, and the control component is used to control the mixing device 2 to continuously discharge the material to the roller coating device 3.

[0068] Furthermore, the mixing device 2 is provided with a solid-liquid mixing chamber 201 for preparing a potassium hydroxide solution, a primary hydrolysis chamber 202 for preparing a silicone oil alkaline solution A, and a secondary hydrolysis chamber 203 for preparing a silicone oil alkaline solution B in sequence from top to bottom.

[0069] The solid-liquid mixing bin 201 is connected with a feeding pipe 205 for automatically introducing a quantitative solvent water into the bin body and a quantitative feeding cylinder 206 for automatically introducing a quantitative potassium hydroxide into the bin body, and both the feeding pipe 205 and the quantitative feeding cylinder 206 are controlled by the control component. A stirring paddle 207 capable of stirring the solvent water and potassium hydroxide is arranged in the solid-liquid mixing bin 201, and an automatic unloading pipe 204 is connected to the bottom of the solid-liquid mixing bin 201, and the solid-liquid mixing bin 201 can be connected to the primary hydrolysis bin 202 through the automatic unloading pipe 204, and the automatic unloading pipe 204 is in communication connection with the control component.

[0070] The primary hydrolysis chamber 202 is connected with a feeding pipe 205 for automatically introducing a certain amount of methyl hydrogenated silicone oil into the chamber body, and the feeding pipe 205 is controlled by the control component. The primary hydrolysis chamber 202 is provided with a stirring paddle 207 capable of stirring the methyl hydrogenated silicone oil and the potassium hydroxide solution, and the bottom of the primary hydrolysis chamber 202 is connected with an automatic feeding pipe 204, and the primary hydrolysis chamber 202 can be connected to the secondary hydrolysis chamber 203 through the automatic feeding pipe 204, and the automatic feeding pipe 204 is in communication connection with the control component.

[0071] The secondary hydrolysis chamber 203 is connected with a feeding pipe 205 for automatically introducing a certain amount of stirring water into the chamber body, and the feeding pipe 205 is controlled by the control component. A stirring paddle 207 capable of stirring the silicone oil alkaline solution A and the stirring water is arranged in the secondary hydrolysis chamber 203, and an automatic unloading pipe 204 is connected to the top of the secondary hydrolysis chamber 203, and the secondary hydrolysis chamber 203 is connected to the roller coating device 3.

[0072] Specifically, the specific working arrangement of the mixing device 2 is as follows:

[0073] 1. The feeding pipe on the solid-liquid mixing bin 201, the quantitative feeding cylinder 206, the feeding pipe 205 on the secondary hydrolysis bin 203, and the feeding pipe 205 on the primary hydrolysis bin 202 are opened at the same time to feed the materials, and are closed after the feeding is completed;

[0074] 2. After the 20% potassium hydroxide solution by mass in the solid-liquid mixing bin 201 is mixed, the automatic feeding pipe 204 arranged at the bottom of the solid-liquid mixing bin 201 is opened, and the potassium hydroxide solution enters the primary hydrolysis bin 202 and mixes with the methyl hydrogen silicone oil;

[0075] 3. After mixing for 5 minutes, a silicone oil alkaline solution A is obtained, and the automatic feeding pipe 204 arranged at the bottom of the primary hydrolysis tank 202 is opened, and the silicone oil alkaline solution A enters the secondary hydrolysis tank 203 and mixes with the stirring water;

[0076] 4. After mixing for 10 minutes, a silicone oil alkaline solution B is obtained, and the roller coating device 3 roller-coats the silicone oil alkaline solution B onto the upper face paper of the wet plate.

[0077] In the present invention, although the loading pipes and automatic unloading pipes of each silo are not named separately, it is obvious that the loading pipes in each silo work together but the medium extracted and the amount of the medium are different, while the automatic unloading pipes have the same function but different switching times. The amount of extracted medium and their respective switching times are controlled by the control component, and the control component can be changed with the transport speed of the wet plate, etc. These parameters can be freely set according to the needs of the factory.

[0078] In order to control production costs, a liquid level sensor 5 is provided in the secondary hydrolysis chamber 203, and the liquid level sensor 5 is communicatively connected with the control component. When the solution height in the secondary hydrolysis chamber 203 is lower than the liquid level sensor 5, the liquid level sensor 5 sends a loading signal to the control component, and the control component controls the quantitative loading cylinder 206 and the loading pipe 205 to perform a single loading, and the automatic unloading pipes 204 from top to bottom are opened in sequence to realize a single replenishment of the secondary hydrolysis chamber 203. After the replenishment is completed, the solution height in the secondary hydrolysis chamber 203 is higher than the liquid level sensor 5.

[0079] During the feeding process, the secondary hydrolysis chamber 203 can also continue to discharge materials, and the roller coating process is continuous.

[0080] Furthermore, in order to facilitate roller coating, the roller coating equipment 3 includes a bracket 301 installed on the conveying device 1, the bracket 301 spans the conveying device 1 and can be suspended above the wet plate, a roughening roller 303 is rotatably installed in the bracket 301 through a bearing 302, and a liquid outlet 304 is connected above the roughening roller 303. The bottom of the roughening roller 303 can be arranged in contact with the wet plate. When the wet plate moves, the roughening roller 303 can move simultaneously under the action of friction.

[0081] The liquid outlet 304 is connected to the secondary hydrolysis chamber 203 through the feed channel 305. A valve 306 is provided in the feed channel 305. The valve 306 is communicated with the control component. The control component can control the opening and closing of the valve 306. During the working process, the valve 306 is continuously in an open state.

[0082] A roller 307 is provided at the liquid outlet 304, and the outer wall of the roller 307 is fitted with the roughening roller 303. When the roughening roller 303 rolls, it can drive the roller 307 to roll in the unloading channel 305 and drive the silicone oil alkaline solution B to flow out from the liquid outlet 304. The silicone oil alkaline solution B is absorbed by the roughening roller 303 and rolled onto the wet plate, thereby realizing continuous rolling coating of the wet plate.

[0083] Through the continuous production method and system of the hydrophobic film on the surface of the paper-faced gypsum board of this embodiment, the continuous roller coating of the lower protective paper of the wet board can be achieved during the wet board transportation process, without the need to process the protective paper in advance. At the same time, the surface hydrophobic film rolled on the gypsum board can consume steam without affecting the circulation of steam, reduce the accumulation of steam, and improve the connection effect between the lower protective paper and the gypsum board core.

[0084] The above embodiments are only exemplary embodiments of the present application and are not intended to limit the present application. The protection scope of the present application is defined by the claims. Those skilled in the art may make various modifications or equivalent substitutions to the present application within the essence and protection scope of the present application, and such modifications or equivalent substitutions shall also be deemed to fall within the protection scope of the present application.

Claims

1. A method for continuously producing a hydrophobic film on the surface of a gypsum board, characterized in that: The steps include: Dissolve potassium hydroxide in solvent water to obtain a potassium hydroxide solution with a mass fraction of 20%; Putting methyl hydrogenated silicone oil into the potassium hydroxide solution for the first hydrolysis, stirring evenly, to obtain silicone oil alkaline solution A, wherein the silicone oil alkaline solution A contains Si-H groups; The silicone oil alkaline solution A is added to the stirred water for a second hydrolysis, whereby part of the Si-H groups in the silicone oil alkaline solution A are hydrolyzed into Si-OH groups, and the solution is stirred evenly to obtain a silicone oil alkaline solution B; The silicone oil alkaline solution B is evenly applied to the wet plate by a roller coating device to form a film at high temperature, and the remaining Si-H groups in the silicone oil alkaline solution B and the water vapor generated by the wet plate at high temperature are hydrolyzed for the third time to obtain a dry plate and a surface hydrophobic film fixed on the dry plate; Part of the Si-OH groups hydrolyzed for the third time can combine with the face paper fibers on the wet plate, and the remaining Si-OH groups form a stable -Si-O- covalent network through self-condensation to cover the surface of the dry plate, thereby achieving the fixation of the surface hydrophobic film on the dry plate; The wet board is an undried gypsum board; In terms of weight ratio, during the first hydrolysis process, the ratio of the potassium hydroxide solution to the methyl hydrogen silicone oil is 1:5; During the second hydrolysis process, the ratio of the silicone oil alkaline solution A to the stirred water is 1:

2.

2. The method for continuously producing a hydrophobic film on the surface of a gypsum board according to claim 1, characterized in that: The silicone oil alkaline solution B was roll-coated onto the surface of the lower face paper of the wet plate.

3. The method for continuously producing a hydrophobic film on the surface of a gypsum board according to claim 2, characterized in that: During the high-temperature film forming process, the remaining water vapor overflows from the bottom of the wet plate until the wet plate forms the dry plate.

4. A system for the continuous production method of a hydrophobic film on the surface of a gypsum board according to any one of claims 1 to 3, characterized in that: include: A mixing device (2) for continuously producing a silicone oil alkaline solution B and a conveying device (1) for continuously conveying a wet plate, wherein the mixing device (2) is connected to the conveying device (1) via a roller coating device (3), the mixing device (2) conveys the silicone oil alkaline solution B into the roller coating device (3), and the roller coating device (3) roller-coats the silicone oil alkaline solution B onto the lower face paper of the wet plate located on the conveying device (1); A dryer (4) is installed downstream of the conveying device (1), and the dryer (4) is used to dry the wet plate after the silicone oil alkaline solution B is roller-coated, and the silicone oil alkaline solution B forms a film on the wet plate at a high temperature; It also comprises a control component, which is in communication connection with the mixing device (2), and is used to control the mixing device (2) to continuously discharge material to the roller coating device (3).

5. The system of the method for continuously producing a hydrophobic film on the surface of a gypsum board according to claim 4, characterized in that: The mixing device (2) is provided with a solid-liquid mixing chamber (201) for preparing a potassium hydroxide solution, a primary hydrolysis chamber (202) for preparing a silicone oil alkaline solution A, and a secondary hydrolysis chamber (203) for preparing the silicone oil alkaline solution B in sequence from top to bottom, the secondary hydrolysis chamber (203) is connected to the roller coating device (3), and the solid-liquid mixing chamber (201), the primary hydrolysis chamber (202), and the secondary hydrolysis chamber (203) are connected in sequence through an automatic unloading pipe (204); The primary hydrolysis chamber (202) and the secondary hydrolysis chamber (203) are both externally connected with a feeding pipe (205), and the feeding pipe (205) can simultaneously add required materials to the solid-liquid mixing chamber (201), the primary hydrolysis chamber (202) and the secondary hydrolysis chamber (203); the solid-liquid mixing chamber (201) is provided with a quantitative feeding cylinder (206) capable of passing a quantitative amount of materials into the solid-liquid mixing chamber (201); The automatic unloading pipe (204), the quantitative loading cylinder (206) and the loading pipe (205) are all connected to the control component.

6. The system of the method for continuously producing a hydrophobic film on the surface of a gypsum board according to claim 5, characterized in that: A liquid level sensor (5) is provided in the secondary hydrolysis chamber (203), and the liquid level sensor (5) is communicatively connected with the control component; When the solution level in the secondary hydrolysis chamber (203) is lower than the liquid level sensor (5), the liquid level sensor (5) sends a loading signal to the control component, and the control component controls the quantitative loading cylinder (206) and the loading pipe (205) to perform a single loading, and the automatic unloading pipes (204) from top to bottom are opened in sequence to realize a single replenishment of the secondary hydrolysis chamber (203).

7. A method and system for continuously producing a hydrophobic film on the surface of a gypsum board according to claim 6, characterized in that: The roller coating device (3) comprises a bracket (301) mounted on the conveying device (1), the bracket (301) spanning the conveying device (1) and being able to be suspended above the wet plate, a roughening roller (303) being rotatably mounted in the bracket (301) via a bearing (302), a liquid outlet (304) being connected to the top of the roughening roller (303), and the bottom of the roughening roller (303) being able to be arranged in contact with the wet plate; The liquid outlet (304) is connected to the secondary hydrolysis chamber (203) through a feed channel (305), a valve (306) is provided in the feed channel (305), and the valve (306) is communicatively connected to the control component; A roller (307) is provided at the liquid outlet (304), and the outer wall of the roller (307) is arranged in contact with the roughening roller (303). When the roughening roller (303) is rolled, it can drive the roller (307) to roll in the unloading channel (305) and drive the silicone oil alkaline solution B to flow out from the liquid outlet (304). The silicone oil alkaline solution B is absorbed by the roughening roller (303) and rolled onto the wet plate.

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