Preparation method and system of waterproof gypsum board

Abstract

The invention discloses a method for preparing a surface waterproof gypsum board, comprising the following steps: introducing methyl hydrogen silicone oil mixed in an alkaline aqueous solution to a roller coating device; applying methyl hydrogen silicone oil to the upper surface of the lower face paper that is about to pass through a forming table by the roller coating device; preliminarily forming the waterproof lower face paper containing gypsum paste by the forming table to obtain a primary gypsum board; drying the primary gypsum board to obtain a surface waterproof gypsum board; wherein, during the drying process, Si-H in the methyl hydrogen silicone oil is further hydrolyzed, so that the waterproof film forms a surface hydrophobic film on the board core of the primary gypsum board; and also discloses a preparation system for the surface waterproof gypsum board. The invention realizes that materials are continuously stacked at a high place, so that they are transmitted to a low place and automatically separated and fall to a material transmission belt for transmitting to a specified position, and no manual auxiliary separation operation is required, the structural principle is simple, and the cost is low.

Description

Technical Field

[0001] The invention relates to the field of gypsum board production, and in particular to a preparation method and system of a paper-faced gypsum board with waterproof surface. Background Art

[0002] The gypsum boards used in the market today are divided into ordinary gypsum boards, moisture-resistant gypsum boards, water-resistant gypsum boards, fire-resistant gypsum boards, water-resistant and fire-resistant gypsum boards, etc. according to their functions. Whether ordinary or functional gypsum boards, their main components are gypsum and face paper and some additives. Since gypsum materials have the characteristic of easy moisture absorption, especially in a humid environment, the face paper also has the characteristic of easy moisture absorption. Most of the face paper is hydrophilic, and moisture will penetrate through the paper surface into the gypsum core layer.

[0003] In order to reduce the water absorption rate of the face paper, there is a kind of water-resistant paper-faced gypsum board, in which hydrophobic materials are added to the gypsum board during production, so that the board body of the gypsum board has certain water-resistant properties. However, although the water absorption rate of the board core of this water-resistant paper-faced gypsum board is reduced to less than 10% by adding waterproof materials, and the surface water absorption can also meet the standard, the surface of the face paper is still easy to get wet. Over time, moisture can easily penetrate from the face paper to the board core, destroying the adhesion between the paper surface and the gypsum, destroying the connection between the gypsum molecules, and affecting normal use.

[0004] With respect to the existing production technology and processes, in order to produce qualified water-resistant paper-faced gypsum boards, waterproof facing paper can be used directly. However, due to the large amount of facing paper used, this type of waterproof facing paper is generally imported material, resulting in high production costs and difficulty in promotion. Moreover, when the gypsum board is being dried, it is difficult for the water-resistant facing paper to discharge moisture from the inside, which can easily cause the facing paper to detach from the board core that is emitting water vapor, thereby destroying the adhesion between the paper surface and the gypsum. Summary of the invention

[0005] The object of the present invention is to provide a method and system for preparing a paper-faced gypsum board with a waterproof surface, so as to solve the technical problem in the prior art that the bonding between the face paper and the gypsum board core is easily destroyed by moisture.

[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 preparing a surface waterproof gypsum board, comprising the following steps:

[0008] Passing methyl hydrogen silicone oil mixed in alkaline aqueous solution into a roller coating device;

[0009] The upper surface of the lower face paper that is about to pass through the forming table is coated with the methyl hydrogen silicone oil by the roller coating device, and Si—H in the methyl hydrogen silicone oil is hydrolyzed to form a primary waterproof film on the lower face paper;

[0010] Spraying gypsum plaster onto the lower protective paper containing the primary waterproof membrane, and preliminarily shaping the waterproof lower protective paper containing the gypsum plaster to obtain a primary gypsum board;

[0011] Drying the primary gypsum board to obtain a paper-faced gypsum board with a waterproof surface;

[0012] During the drying process, Si—H in the methyl hydrogen silicone oil is further hydrolyzed, so that the waterproof film forms a surface hydrophobic film on the core of the primary gypsum board.

[0013] As a preferred embodiment of the present invention, the methyl hydrogen silicone oil is hydrolyzed step by step on the lower face paper;

[0014] Wherein, when the methyl hydrogen silicone oil is fully coated on the surface of the lower protective paper, the methyl hydrogen silicone oil is initially hydrolyzed, that is, Si-H is initially hydrolyzed into Si-OH groups, and the Si-OH groups are combined with the fibers of the lower protective paper to form a primary waterproof film;

[0015] When the primary gypsum board is dried, the remaining Si—H is hydrolyzed into Si—OH groups for the second time, and the Si—OH groups are further combined with the lower facing paper fibers to form a secondary waterproof membrane.

[0016] As a preferred embodiment of the present invention, the secondary hydrolysis process further comprises the following steps:

[0017] During the drying process, the Si-OH groups self-condense to form a stable -Si-O- covalent network covering the core surface of the primary gypsum board;

[0018] The core of the primary gypsum board containing the -Si-O- covalent network is combined with the lower face paper containing the secondary waterproof membrane to form a paper-faced gypsum board with surface waterproofing.

[0019] The present invention also provides a system for preparing a surface waterproof gypsum board. According to the preparation sequence, the system comprises:

[0020] A paper roll stand, a roller coating device, a forming table, and a dryer; the paper roll stand, the roller coating device, the forming table, and the dryer are connected by a conveying device;

[0021] The paper roll holder is used to install the lower face paper;

[0022] The roller coating device is arranged between the paper roll stand and the forming table, and is used to fully coat the methyl hydrogen silicone oil mixed in the alkaline aqueous solution on the surface of the lower face paper, and the methyl hydrogen silicone oil can be preliminarily hydrolyzed on the surface of the lower face paper to form a primary waterproof film;

[0023] The forming table is provided with a discharging machine, and the discharging machine is used to spray gypsum paste on the surface of the lower face paper passing through the forming table, and the forming table is used to preliminarily form the lower face paper containing the gypsum paste and obtain a primary gypsum board;

[0024] The dryer is used to dry the primary gypsum board at high temperature. During the drying process, the water vapor in the core of the primary gypsum board evaporates and undergoes secondary hydrolysis with the methyl hydrogen silicone oil to form a paper-faced gypsum board with a waterproof surface.

[0025] As a preferred solution of the present invention, a roller printing machine is arranged between the paper roll stand and the forming table, and the roller printing machine is used to apply roller printing to the lower face paper, and the lower face paper is in a flat state when the lower face paper passes through the roller printing machine;

[0026] The height of the roller printing machine is higher than that of the paper roll rack. When the lower face paper passes through the roller printing machine, it climbs upward to form an inclined area. The lower face paper located in the inclined area is subjected to an inclined upward pulling force. The roller coating device is installed in the inclined area and is in pressure contact with the lower face paper in the inclined area.

[0027] As a preferred solution of the present invention, the roller coating device includes a roller arranged between the roller printing machine and the paper roll stand, the roller is used to fit on the lower face paper arranged in the inclined area and is arranged above the lower face paper, when the lower face paper is pulled upward, the lower face paper drives the roller to rotate;

[0028] The roller is connected to a feeding assembly, which is used to feed the roller so that its surface has methyl hydrogen silicone oil mixed in an alkaline solution. When the lower face paper passes through the roller, the methyl hydrogen silicone oil on the roller is rolled onto the lower face paper.

[0029] As a preferred solution of the present invention, the roller comprises a bracket installed between the roller printing machine and the paper roll stand, a roller is rotatably arranged on the bracket, a brush layer is sleeved and installed on the outer wall of the roller, and the brush layer is connected to the feeding component and is used to absorb the methyl hydrogen silicone oil;

[0030] The brush layer is arranged in contact with the lower protective paper located in the inclined area, and the brush layer applies a downward pressure perpendicular to the inclined direction of the lower protective paper to the lower protective paper, and when the lower protective paper moves, the brush layer drives the roller to rotate on the bracket under the action of friction, and at the same time, the methyl hydrogen silicone oil on the brush layer is applied to the surface of the lower protective paper.

[0031] As a preferred solution of the present invention, the feeding assembly comprises a shell semi-enclosed on the outer wall of the brush layer, the two sides of the shell are fixedly mounted on the bracket, the shell is connected to a feeding pipe, the feeding pipe is used to pass the methyl hydrogen silicone oil into the shell, and the shell is provided with a feeding trough for storing the methyl hydrogen silicone oil;

[0032] Among them, in a stationary state, one side of the brush layer can pass through the outer shell and contact the lower protective paper, the bottom of the brush layer is arranged in the feeding trough and contacts the methyl hydrogen silicone oil retained therein, and when rotating, the brush layer contacts the surface of the lower protective paper after absorbing the methyl hydrogen silicone oil.

[0033] As a preferred solution of the present invention, support rods are rotatably mounted on both sides of the bracket, and the two support rods are connected by a scraper. The scraper is slidably arranged on the lower protective paper, and the scraper is located upstream of the brush layer.

[0034] As a preferred solution of the present invention, a rotating motor is arranged on the bracket, the rotating motor is connected to the drum, and the rotating motor is used to drive the drum to rotate.

[0035] Compared with the prior art, the present invention has the following beneficial effects:

[0036] The present invention applies methyl hydrogen silicone oil mixed with an alkaline solution on the surface of the lower face paper, and the methyl hydrogen silicone oil on the lower face paper reacts with water vapor, so that the water vapor in the board core can be fully utilized during the high-temperature drying process of the gypsum board, and the water vapor is prevented from affecting the bonding between the lower face paper and the gypsum board;

[0037] The methyl hydrogen silicone oil is combined with the fibers of the lower face paper to fix the hydrophobic groups to the surface of the gypsum board, thereby further improving the bonding effect between the gypsum board and the lower face paper, preventing the lower face paper from cracking, and improving the performance of the gypsum board;

[0038] At the same time, the Si-OH group produced by the hydrolysis of methyl hydrogen silicone oil can form a more stable -Si-O- covalent network through self-condensation to cover the surface of the gypsum board, and finally form a hydrophobic film on the surface of the gypsum board, thereby further improving the waterproof effect of the gypsum board and preventing water accumulation on the gypsum board. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] 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.

[0040] Figure 1 The present invention provides a schematic flow diagram of a method for preparing a surface waterproof gypsum board;

[0041] Figure 2 A schematic structural diagram of a system for preparing a surface waterproof gypsum board provided by the present invention;

[0042] Figure 3 The present invention provides Figure 2 A schematic diagram of the internal structure of the roller coating device in the illustrated embodiment;

[0043] Figure 4 The present invention provides Figure 2 A schematic diagram of the internal partial structure of the roller coating device in the illustrated embodiment;

[0044] Figure 5 The present invention provides Figure 2 A schematic diagram of the side structure of the roller coating device in the illustrated embodiment;

[0045] Figure 6 The present invention provides Figure 2 A schematic diagram of the structure of the scraper in the illustrated embodiment.

[0046] The numbers in the figure represent the following:

[0047] 1-paper roll stand; 2-roller coating equipment; 3-forming table; 4-dryer; 5-discharging machine; 6-roller printing machine; 7-support rod; 8-scraper; 9-rotating motor;

[0048] 201- roller; 202- feeding assembly;

[0049] 2011- bracket; 2012- roller; 2013- brush layer;

[0050] 2021-housing; 2022-feeding tube. DETAILED DESCRIPTION

[0051] 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.

[0052] like Figure 1 As shown, the present invention provides a method for preparing a surface waterproof gypsum board, comprising the following steps:

[0053] S100, introducing methyl hydrogen silicone oil mixed in alkaline aqueous solution into a roller coating device;

[0054] S200, fixing the lower face paper in front of the forming table through a paper roll stand, the paper roll stand is arranged upstream of the forming table, and the roller coating device is arranged between the paper roll stand and the forming table;

[0055] S300, applying methyl hydrogen silicone oil to the upper surface of the lower face paper that is about to pass through the forming table by means of a roller coating device, and forming a primary waterproof film on the lower face paper after Si-H in the methyl hydrogen silicone oil is hydrolyzed;

[0056] S400, spraying gypsum paste onto the lower protective paper containing the primary waterproof membrane, preliminarily shaping the waterproof lower protective paper containing the gypsum paste, and obtaining a primary gypsum board;

[0057] S500, drying the primary gypsum board to obtain a paper-faced gypsum board with a waterproof surface;

[0058] During the drying process, Si-H in the methyl hydrogen silicone oil is further hydrolyzed, so that the waterproof membrane forms a surface hydrophobic film on the core of the primary gypsum board.

[0059] Methyl hydrogen silicone oil is generally used in gypsum board to enhance the waterproof ability of the gypsum board core and prevent the internal molecules of the gypsum board from being affected by water vapor. In the prior art, the vast majority of the performance of the gypsum board is provided by the lower face paper, that is, even if the gypsum board is very thin, due to the tension and performance of the face paper, the gypsum board also has good firmness.

[0060] It can be seen that the bonding between the gypsum board core and the facing paper becomes an important part of improving the performance of the gypsum board. In this embodiment, methyl hydrogen silicone oil in an alkaline aqueous solution is applied to the facing paper. In the subsequent drying process, the water in the gypsum paste evaporates to form water vapor. The remaining Si-H groups of the methyl hydrogen silicone oil undergo hydrolysis reaction with the water vapor under alkaline conditions to obtain Si-OH groups with hydrophobic effect. The Si-OH groups can self-condense and form a stable -Si-O- covalent network on the core of the primary gypsum board, so that a waterproof film is formed where the primary gypsum board is wrapped by the lower facing paper. At the same time, the Si-OH groups can combine with the fibers of the lower facing paper so that the lower facing paper is firmly attached to the core of the gypsum board to prevent the lower facing paper from cracking.

[0061] The hydrophobic film prepared by the methyl hydrogen silicone oil of the present invention has the function of reducing the surface energy of the paper-faced gypsum board, so that the surface of the gypsum board is not stained with water, that is, water drops form water beads on the board surface, which can roll away from the board surface at a slight angle and do not stay on the board surface for too long, thereby preventing water from penetrating into the board body of the gypsum board from the front side, and because the Si-OH group can form a stable -Si-O-covalent network on the board core of the primary gypsum board through self-condensation, a waterproof film is formed at the place where the primary gypsum board is wrapped by the lower face paper, so that the bonding between the lower face paper and the board core of the gypsum board is tighter, the performance of the gypsum board is provided by the lower face paper, and the lower face paper is connected to the board core of the gypsum board, so that the lower face paper can better support and protect the gypsum board, and the gypsum board is less likely to crack. Compared with ordinary gypsum boards, the gypsum board of the present invention has more excellent performance.

[0062] In this embodiment, the following steps are also included: the methyl hydrogen silicone oil is hydrolyzed step by step on the lower face paper;

[0063] When the methyl hydrogen silicone oil is fully coated on the surface of the lower protective paper, the methyl hydrogen silicone oil is initially hydrolyzed, that is, Si-H is initially hydrolyzed into Si-OH groups, and the Si-OH groups are combined with the fibers of the lower protective paper to form a primary waterproof film;

[0064] When the primary gypsum board is dried, the remaining Si-H is hydrolyzed into Si-OH groups for the second time, and the Si-OH groups are further combined with the fibers of the lower face paper to form a secondary waterproof membrane.

[0065] Due to the special film-forming properties of methyl hydrogen silicone oil, methyl hydrogen silicone oil can form a film due to hydrolysis when initially applied and be set on the surface of the lower facing paper. In the subsequent drying process, methyl hydrogen silicone oil can be further hydrolyzed. At this time, methyl hydrogen silicone oil can adhere to the surface of the gypsum board to form a film, and at the same time form a stable -Si-O- covalent network on the surface of the gypsum board, firmly bonding the facing paper and the gypsum board together, which can not only absorb the moisture generated during drying to prevent cracking between the facing paper and the board core, but also prevent the subsequent moisture from entering the connection between the board core and the lower facing paper, thereby improving the performance of the gypsum board.

[0066] In this embodiment, the secondary hydrolysis process further includes the following steps:

[0067] During the drying process, Si-OH groups self-condense to form a stable -Si-O- covalent network covering the core surface of the primary gypsum board;

[0068] The board core of the primary gypsum board containing the -Si-O- covalent network is combined with the lower face paper containing the secondary waterproof membrane to form a paper-faced gypsum board with surface waterproofing.

[0069] The present invention provides a method for preparing a paper-faced gypsum board with a waterproof surface. The method can fully utilize the water vapor in the board core during the high-temperature drying of the gypsum board. The methyl hydrogen silicone oil on the lower facing paper reacts with the water vapor and combines with the fibers of the lower facing paper to fix the hydrophobic groups to the surface of the gypsum board, thereby improving the bonding effect between the gypsum board and the lower facing paper, preventing the lower facing paper from cracking, and improving the performance of the gypsum board.

[0070] In addition, the Si-OH groups generated by the hydrolysis of methyl hydrogen silicone oil form a more stable -Si-O- covalent network through self-condensation and cover the surface of the gypsum board, eventually forming a hydrophobic film on the surface of the gypsum board, thereby further improving the waterproof effect of the gypsum board and preventing water accumulation on the gypsum board.

[0071] It is not easy for existing technicians to think of the method of applying methyl hydrogen silicone oil on the surface. Firstly, methyl hydrogen silicone oil is mainly used in the material preparation stage of gypsum board to improve the waterproof performance of the board core itself, so it is not easy to think of methyl hydrogen silicone oil separately. Secondly, the application of methyl hydrogen silicone oil will increase the production steps of gypsum board, and the complicated production steps will also affect the production cost of gypsum board.

[0072] In order to simplify the production steps, such as Figures 2 to 6 As shown, the present invention provides a system for preparing a surface waterproof gypsum board. According to the preparation sequence, the preparation system includes a paper roll stand 1, a roller coating device 2, a forming table 3, and a dryer 4. The paper roll stand 1, the roller coating device 2, the forming table 3, and the dryer 4 are connected by a conveying device.

[0073] The paper roll stand 1 is used to install the lower face paper. The conveying device can be used to convey the lower face paper throughout the entire process and change the moving direction of the lower face paper.

[0074] The roller coating device 2 is arranged between the paper roll rack 1 and the forming table 3. The roller coating device 2 is used to fully coat the methyl hydrogen silicone oil mixed in the alkaline aqueous solution on the surface of the lower face paper. The methyl hydrogen silicone oil can be preliminarily hydrolyzed on the surface of the lower face paper to form a primary waterproof film.

[0075] The forming table 3 is provided with a discharging machine 5, which is used to spray gypsum paste on the surface of the lower face paper passing through the forming table 3. The forming table 3 is used to preliminarily form the lower face paper containing the gypsum paste and obtain a primary gypsum board. The conveying device conveys the primary gypsum board to the dryer 4.

[0076] The dryer 4 is used to dry the primary gypsum board at high temperature. During the drying process, the water vapor in the core of the primary gypsum board evaporates and undergoes secondary hydrolysis with the methyl hydrogen silicone oil to form a paper-faced gypsum board with a waterproof surface.

[0077] The present invention achieves treatment of the lower face paper by arranging a device for roller coating methyl hydrogen silicone oil mixed in an alkaline aqueous solution in front of a forming table during the process of conveying the lower face paper. After the lower face paper is treated, the gypsum board is normally formed and dried after forming. When the finished gypsum board is obtained, the forming of a hydrophobic film on the gypsum board is achieved. The preparation steps are simple, the device is easy to install, only one step is added, and the production cost is saved.

[0078] Since it is necessary to fully coat the lower face paper with methyl hydrogen silicone oil, after many experiments, it was found that only rolling the methyl hydrogen silicone oil on a flat surface would lead to uneven distribution of the methyl hydrogen silicone oil. In order to make the distribution of the methyl hydrogen silicone oil more uniform, a roller printing machine 6 is arranged between the paper roll rack 1 and the forming table 3. The roller printing machine 6 is used to apply roller printing to the lower face paper. When the lower face paper passes through the roller printing machine 6, the lower face paper is in a flat state.

[0079] In particular, the height of the roller printing machine 6 is higher than the paper roll rack 1. When the lower face paper passes through the roller printing machine 6, it climbs upward to form an inclined area. The lower face paper located in the inclined area is subjected to an inclined upward pulling force. The roller coating device 2 is installed in the inclined area and is in pressure contact with the lower face paper in the inclined area, so that the methyl hydrogen silicone oil can be more evenly distributed on the surface of the lower face paper during roller coating without being affected by the roller pressure.

[0080] Furthermore, the roller coating device 2 includes a roller 201 arranged between the roller printing machine 6 and the paper roll rack 1, and the roller 201 is used to fit on the lower protective paper arranged in the inclined area and is arranged above the lower protective paper. When the lower protective paper moves upward under the pulling force, the lower protective paper drives the roller 201 to rotate.

[0081] The roller 201 is connected to a feeding assembly 202, which is used to feed the roller 201 so that its surface has methyl hydrogen silicone oil mixed in an alkaline solution. When the lower face paper passes through the roller 201, the methyl hydrogen silicone oil on the roller 201 is rolled onto the lower face paper.

[0082] When the lower face paper moves upward under the pulling force, the roller 201 fits against the lower face paper. At this time, the lower face paper is subjected to forces in two directions, one is the upward pulling force, and the other is the pressure of the roller 201. At this time, there is no need to precisely set and calculate the pressure of the roller 201. The lower face paper will automatically deform as the pressure changes, thereby making the coating more uniform and reducing the purchase and setting costs of the device.

[0083] Specifically, the roller 201 includes a bracket 2011 installed between the roller printing machine 6 and the paper roll rack 1, a roller 2012 is rotatably installed on the bracket 2011, and a brush layer 2013 is sleeved on the outer wall of the roller 2012. The brush layer 2013 is connected to the feeding component 202 and is used to absorb methyl hydrogen silicone oil.

[0084] The brush layer 2013 is fitted to the lower protective paper located in the inclined area, and the brush layer 2013 applies a downward pressure perpendicular to the inclined direction of the lower protective paper to the lower protective paper, and when the lower protective paper moves, the brush layer 2013 drives the roller 2012 to rotate on the bracket 2011 under the action of friction, and at the same time, the methyl hydrogen silicone oil on the brush layer 2013 is smeared onto the surface of the lower protective paper.

[0085] The feeding assembly 202 is used to convey methyl hydrogen silicone oil to the brush layer 2013 so that the methyl hydrogen silicone oil can be conveyed onto the lower face paper. However, when conveying the methyl hydrogen silicone oil, if the brush layer 2013 absorbs unevenly, it will also cause uneven application. In order to solve the problem of uniformity when the brush layer 2013 absorbs the solution, the feeding assembly 202 includes a shell 2021 half-enclosed on the outer wall of the brush layer 2013, and both sides of the shell 2021 are fixedly mounted on the bracket 2011. The shell 2021 is connected to a feeding pipe 2022, which is used to pass the methyl hydrogen silicone oil into the shell 2021, and a feeding trough for the methyl hydrogen silicone oil to be stored is provided in the shell 2021.

[0086] Among them, in a static state, one side of the brush layer 2013 can pass through the outer shell 2021 and contact the lower protective paper, and the bottom of the brush layer 2013 is set in the feeding trough and contacts the methyl hydrogen silicone oil retained therein. When rotating, the brush layer 2013 contacts the surface of the lower protective paper after uniformly absorbing the methyl hydrogen silicone oil, thereby achieving uniform filling and roller coating.

[0087] In order to prevent excessive accumulation of methyl hydrogen silicone oil on the lower face paper, support rods 7 are rotatably mounted on both sides of the bracket 2011. The two support rods 7 are connected by a scraper 8. The scraper 8 is slidably arranged on the lower face paper. The scraper 8 is located upstream of the brush layer 2013. The scraper 8 is used to scrape off the excess methyl hydrogen silicone oil that has not formed a film. The shaded position in the housing 2021 in the figure is the methyl hydrogen silicone oil that is added.

[0088] In order to prevent the brush layer 2013 from not having enough friction and thus stopping rotation, a rotating motor 9 is provided on the bracket 2011 . The rotating motor 9 is connected to the roller 2012 and is used to drive the roller 2012 to rotate.

[0089] Through the preparation method and system of the surface waterproof gypsum board of this embodiment, it is possible to fully utilize the water vapor in the board core during the high-temperature drying process of the gypsum board, prevent the water vapor from affecting the bonding between the lower facing paper and the gypsum board, and improve the bonding effect between the gypsum board and the lower facing paper, prevent the lower facing paper from cracking, and improve the performance of the gypsum board.

[0090] 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 system for preparing a waterproof gypsum board, characterized in that: The preparation system comprises: A paper roll stand (1), a roller coating device (2), a forming table (3), and a dryer (4); the paper roll stand (1), the roller coating device (2), the forming table (3), and the dryer (4) are connected via a conveying device; The paper roll holder (1) is used to install the lower face paper; The roller coating device (2) is arranged between the paper roll stand (1) and the forming table (3), and is used to fully coat the surface of the lower protective paper with methyl hydrogen silicone oil mixed in an alkaline aqueous solution, wherein the methyl hydrogen silicone oil can be preliminarily hydrolyzed on the surface of the lower protective paper to form a primary waterproof film; The molding table (3) is provided with a discharge machine (5), the discharge machine (5) is used to spray gypsum paste on the surface of the lower face paper passing through the molding table (3), the molding table (3) is used to perform preliminary molding on the lower face paper containing the gypsum paste, and obtain a primary gypsum board; The dryer (4) is used to dry the primary gypsum board at high temperature. During the drying process, the water vapor in the core of the primary gypsum board evaporates and undergoes secondary hydrolysis with the methyl hydrogen silicone oil to form a paper-faced gypsum board with a waterproof surface. A roller printing machine (6) is arranged between the paper roll stand (1) and the forming table (3), and the roller printing machine (6) is used to apply roller printing to the lower face paper, and when the lower face paper passes through the roller printing machine (6), the lower face paper is in a flat state; The height of the roller printing machine (6) is higher than that of the paper roll stand (1); when the lower face paper passes through the roller printing machine (6), it climbs upward to form an inclined area; the lower face paper located in the inclined area is subjected to an inclined upward pulling force; the roller coating device (2) is installed in the inclined area and is in pressure contact with the lower face paper in the inclined area; The roller coating device (2) comprises a roller (201) arranged between the roller printing machine (6) and the paper roll stand (1), the roller (201) being used to fit on the lower face paper arranged in the inclined area and being arranged above the lower face paper, and when the lower face paper is moved upward by a pulling force, the lower face paper drives the roller (201) to rotate; The roller (201) is connected to a feeding assembly (202), and the feeding assembly (202) is used to feed material to the roller (201) so that the surface of the roller has methyl hydrogen silicone oil mixed in an alkaline solution, and when the lower face paper passes through the roller (201), the methyl hydrogen silicone oil on the roller (201) is rolled onto the lower face paper; The roller (201) comprises a support (2011) installed between the roller printing machine (6) and the paper roll stand (1), a roller (2012) being rotatably mounted on the support (2011), a brush layer (2013) being sleeved and mounted on the outer wall of the roller (2012), the brush layer (2013) being connected to the feeding component (202) and being used to absorb the methyl hydrogenated silicone oil; The brush layer (2013) is arranged in contact with the lower protective paper located in the inclined area, and the brush layer (2013) applies downward pressure perpendicular to the inclined direction of the lower protective paper to the lower protective paper, and when the lower protective paper moves, the brush layer (2013) drives the roller (2012) to rotate on the bracket (2011) under the action of friction, and at the same time, the methyl hydrogen silicone oil on the brush layer (2013) is applied to the surface of the lower protective paper.

2. A system for preparing a surface waterproof gypsum board according to claim 1, characterized in that: The feeding component (202) comprises a shell (2021) semi-enclosed on the outer wall of the brush layer (2013), two sides of the shell (2021) are fixedly mounted on the bracket (211), the shell (2021) is connected to a feeding pipe (2022), the feeding pipe (2022) is used to pass the methyl hydrogenated silicone oil into the shell (2021), and the shell (2021) is provided with a feeding trough for storing the methyl hydrogenated silicone oil; In which, in a stationary state, one side of the brush layer (2013) can pass through the outer shell (2021) to contact the lower protective paper, and the bottom of the brush layer (2013) is arranged in the loading trough and contacts the methyl hydrogen silicone oil retained therein, and when rotating, the brush layer (2013) contacts the surface of the lower protective paper after absorbing the methyl hydrogen silicone oil.

3. A system for preparing a surface waterproof gypsum board according to claim 2, characterized in that: Support rods (7) are rotatably mounted on both sides of the bracket (2011); the two support rods (7) are connected via a scraper (8); the scraper (8) is slidably arranged on the lower protective paper; the scraper (8) is located upstream of the brush layer (2013).

4. A system for preparing a surface waterproof gypsum board according to claim 1, characterized in that: A rotating motor (9) is provided on the bracket (2011), the rotating motor (9) is connected to the roller (2012), and the rotating motor (9) is used to drive the roller (2012) to rotate.

5. A method for preparing a surface waterproof gypsum board, using the surface waterproof gypsum board preparation system according to any one of claims 1 to 4, characterized in that: The steps include: Passing methyl hydrogen silicone oil mixed in alkaline aqueous solution into a roller coating device; The upper surface of the lower face paper that is about to pass through the forming table is coated with the methyl hydrogen silicone oil by the roller coating device, and Si—H in the methyl hydrogen silicone oil is hydrolyzed to form a primary waterproof film on the lower face paper; Spraying gypsum plaster onto the lower protective paper containing the primary waterproof membrane, and preliminarily shaping the waterproof lower protective paper containing the gypsum plaster to obtain a primary gypsum board; Drying the primary gypsum board to obtain a paper-faced gypsum board with a waterproof surface; During the drying process, Si—H in the methyl hydrogen silicone oil is further hydrolyzed, so that the waterproof film forms a surface hydrophobic film on the core of the primary gypsum board.

6. The method for preparing a surface waterproof gypsum board according to claim 5, characterized in that: The methyl hydrogen silicone oil is hydrolyzed step by step on the lower face paper; Wherein, when the methyl hydrogen silicone oil is fully coated on the surface of the lower protective paper, the methyl hydrogen silicone oil is initially hydrolyzed, that is, Si-H is initially hydrolyzed into Si-OH groups, and the Si-OH groups are combined with the fibers of the lower protective paper to form a primary waterproof film; When the primary gypsum board is dried, the remaining Si-H is hydrolyzed into Si-OH groups for the second time, and the Si-OH groups are further combined with the lower facing paper fibers to form a secondary waterproof membrane.

7. The method for preparing a surface waterproof gypsum board according to claim 6, characterized in that: The secondary hydrolysis process also includes the following steps: During the drying process, the Si-OH groups self-condense to form a stable -Si-O- covalent network covering the core surface of the primary gypsum board; The core of the primary gypsum board containing the -Si-O- covalent network is combined with the lower face paper containing the secondary waterproof membrane to form a paper-faced gypsum board with surface waterproofing.

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