阅读说明：本技术 高饱和度石墨烯油墨在白板纸上的涂覆方法 (Coating method of high-saturation graphene ink on white board paper ) 是由 胡鑫 于 2021-08-25 设计创作，主要内容包括：本发明公开了高饱和度石墨烯油墨在白板纸上的涂覆方法,包括如下步骤：步骤1：预涂石墨烯油墨以及表层石墨烯油墨的制备：步骤2：制备白板纸纸基；步骤3：对步骤2白板纸纸基表面性状进行检测；步骤4：形成一石墨烯预涂层；并干燥；步骤5：在石墨烯预涂层上多孔结构制备；并干燥；步骤6：在步骤5中的石墨烯预涂层上继续涂覆一层石墨烯油墨；并干燥；本申请印刷时,对纸基表面形状进行实时检测,以保证油墨具备良好的附着基地；其次,采用多次涂布的方式结合在各层涂层之间形成多孔结构；由于多层涂覆使得隔层的厚度显著降低,附着力增强,同时配合多孔结构使得各层涂层之间结合更牢固；从而制得高品质石墨烯特种纸。(The invention discloses a method for coating high-saturation graphene ink on white board paper, which comprises the following steps: step 1: preparation of pre-coated graphene ink and surface graphene ink: step 2: preparing a white board paper base; and step 3: detecting the surface properties of the white board paper base in the step 2; and 4, step 4: forming a graphene precoat; and drying; and 5: preparing a porous structure on the graphene precoat; and drying; step 6: continuously coating a layer of graphene printing ink on the graphene precoat in the step 5; and drying; when the method is used for printing, the surface shape of the paper base is detected in real time so as to ensure that the printing ink has a good attachment base; secondly, combining the coatings of each layer in a multi-coating mode to form a porous structure; the thickness of the interlayer is obviously reduced due to the multi-layer coating, the adhesive force is enhanced, and the coatings of all layers are combined more firmly by matching with the porous structure; thereby preparing the high-quality graphene specialty paper.)

1. The coating method of the high-saturation graphene ink on the white board paper is characterized by comprising the following steps: the method comprises the following steps:

step 1: preparation of pre-coated graphene ink and surface graphene ink:

step 2: preparing a white board paper base; and finishing the coating; the thickness of the coating layer is 0.01-0.03 mm;

and step 3: detecting the surface properties of the white board paper base in the step 2, and judging the surface flatness of the paper base; if the surface is uneven, adjusting parameters in the previous procedure;

and 4, step 4: uniformly coating the graphene ink on the coating layer of the white board paper base through a coating machine to form a graphene precoating layer; and drying;

and 5: preparing a porous structure on the graphene precoat; and drying;

step 6: continuously coating a layer of graphene printing ink on the graphene precoat in the step 5; and dried.

2. The method for coating the high-saturation graphene ink on the white board paper according to claim 1, wherein the method comprises the following steps: the method for preparing the porous structure in the step 5 is to spray a layer of etching agent on the graphene precoat; after staying for 10-15S, passing through a roughing roller to remove the residual etching agent on the graphene precoating layer; thereby forming a porous structure uniformly distributed on the graphene precoat.

3. The method for coating the high-saturation graphene ink on the white board paper according to claim 1, wherein the method comprises the following steps: the method for detecting the surface property of the base paper and judging the surface evenness of the base paper in the step 3 comprises the following substeps:

s1, taking the standard sample paper base, irradiating with a standard light source;

s2, shooting a surface character image of the sample paper base through a high-definition camera device; extracting the edge of the sample paper base and converting the edge into a standard gray value image;

s3, under the premise of irradiation of the same standard light source; acquiring a surface character image of an actual paper base through an online camera device; extracting the actual paper base edge and converting the actual paper base edge into an actual gray value image; establishing a position coordinate system on the actual gray value image; taking one end point of the actual gray value image as a reference point, and taking the width direction of the actual gray value image as an X axis; taking the length direction of the actual gray value image as a Y axis;

s4, corresponding the actual gray value image and the standard gray value image to a coordinate system one by one;

s5 selecting a pixel of the actual gray image with a gray value of G₀The average gray value G of the standard gray value image is compared with the average gray value G of the standard gray value image_tComparing, if the obtained difference absolute value G_nIf the gray value is less than or equal to 5, taking the changed point as the gray value of the pixel of the reference point, and performing difference comparison operation on the gray value of the pixel of the adjacent point and the gray value of the pixel of the reference point to obtain a difference absolute value T1; and recording the comparison quantity as S1; if T1 is less than or equal to 10; recording the gray value of the adjacent point; if T1 is more than 10, discarding the gray value of the adjacent point; repeating the steps until all the pixel points with the difference absolute value less than or equal to 10 are found; and adjusting the gray value of the pixel points to the average gray value G_tThe same; if G is obtained for the first time_nIs more than 5; then look again until G is found_nA point no more than 5;

s6, carrying out AND operation on the actual gray value image and the standard gray value image to obtain pixel points which are different from the standard gray value image in the actual gray value image; simultaneously obtaining the gray value after the AND operation;

s7, marking the outer contour of each abnormal area; and determining a coordinate region of the abnormal region: thereby obtaining the actual position of the abnormal occurrence; the process parameters can be conveniently adjusted in the actual production line subsequently; the method for determining the coordinate area comprises the following steps: taking the outermost edge points of the upper, lower, left and right sides of the abnormal area as tangent points, making a tangent line, and determining the range occupied by the abnormal area by using coordinates of the tangent line;

s8, judging whether the abnormal area is concave or convex; the central point of the abnormal area is taken as the center of a circle and is radiated outwards in a circle; marking pixel points with the gray value larger than 0 and smaller than 0 after the AND operation respectively; determining that the area formed by the pixel points with the gray value greater than 0 after the AND operation is sunken; and judging the area formed by the pixel points with the gray value less than 0 after the AND operation as the bulge.

4. The method for coating the highly saturated graphene ink on the white board paper according to any one of claims 1 to 3, wherein: the preparation method of the pre-coated graphene ink comprises the following steps:

(a) taking solid graphene oxide; heating solid graphene oxide in an environment of: heating to 1000-1300 ℃ at the speed of 80-200 ℃/min; lasting for 20min-35min, and rapidly cooling;

(b) dispersing the solid graphene oxide subjected to rapid freezing by using an ultrasonic instrument to obtain nano graphene oxide powder;

(c) adding nano graphene oxide powder into the resin slurry; adding a dispersing agent and an auxiliary agent while fully stirring to prepare the pre-coated graphene ink; wherein the mass percent of the nano graphene oxide powder is 25-35%.

Wherein the dispersion time of the ultrasonic instrument is 0.9-1.5H.

5. The method for coating the high-saturation graphene ink on the white board paper according to claim 4, wherein the method comprises the following steps: in the step (a), the temperature is rapidly reduced to 140-280 ℃ below zero in 10-25s under the inert gas environment.

6. The method for coating the high-saturation graphene ink on the white board paper according to claim 4, wherein the method comprises the following steps: the preparation method of the surface graphene ink comprises the following steps:

(d) taking solid graphene oxide; heating solid graphene oxide in an environment of: heating to 800-1100 ℃ at the speed of 150-190 ℃/min; lasting for 20min-35min, and rapidly cooling;

(e) dispersing the solid graphene oxide subjected to rapid freezing by using an ultrasonic instrument to obtain nano graphene oxide powder;

(f) fully mixing nano graphene oxide powder and titanium dioxide, and adding the mixture into resin slurry; adding a dispersing agent and an auxiliary agent while fully stirring to prepare the pre-coated graphene ink; wherein the mass percent of the nano graphene oxide powder is 6-15%.

Technical Field

The invention relates to the technical field of white board paper manufacturing, in particular to a coating method of high-saturation graphene ink on white board paper.

Background

In our daily life, there are different requirements for paper, and the development of special paper industry is promoted, such as special properties of acid resistance, antibiosis, and oleophobic property. On the other hand, the demand of paper in life is large, so that research and production of special paper become a popular industry and research hotspot. The consumption of the special paper and the paperboard is continuously increasing for three years, and the special paper and the paperboard are far ahead of the growth rate of other paper types, and particularly under the condition of bad industrial conditions, the cultural paper with negative growth needs to be converted into the special paper.

In the society with faster and faster life rhythm, fast food culture is extremely prevalent in our cities, in the life style of young people, fast sales, e-commerce and takeout have deeply lived, hamburgers and fast food restaurants are visible anywhere in streets and shopping malls, meanwhile, 2000 cities across the country have been covered by hungry, 130 trillion restaurants are franchised, the user quantity reaches 2.6 billion, and the market is wide. Logistics and treasure panning promote the development of cardboard paper, and I believe that take-out platforms such as hungry and American groups also have requirements and demands on the packaging materials of fast-heating foods. There are many unknown possibilities of graphene, which is called "king of new materials", as a new material, and the paper industry is a traditional industry that is inherited over thousands of years, and needs support of new technologies to realize sustainable development. Although the graphene material still has the difficulties of higher preparation cost and the like in the actual production, with the breakthrough of scientific technology and the mutual cooperation among industries, the development of the special paper based on the graphene material has bright prospect.

Coating the graphene ink on the existing white board paper is the simplest method for manufacturing the special paper, but if the graphene ink is directly coated on the surface of the white board paper, the coating layer is coated on the surface of the white board paper; the adhesiveness is poor, so that the firmness and uniformity of the graphene ink coating after coating are greatly dependent on the performance of the coating layer; how to improve the performance of the graphene printing ink after coating on the white board paper and improve the quality of paper products is an urgent problem to be solved.

Disclosure of Invention

The present invention aims to provide a method for coating highly saturated graphene ink on white board paper, so as to solve the problems in the background art.

In order to achieve the purpose, the invention provides the following technical scheme:

the coating method of the high-saturation graphene ink on the white board paper comprises the following steps:

step 1: preparation of pre-coated graphene ink and surface graphene ink:

step 2: preparing a white board paper base; and finishing the coating; the thickness of the coating layer is 0.01-0.03 mm;

and step 3: detecting the surface properties of the white board paper base in the step 2, and judging the surface flatness of the paper base; if the surface is uneven, adjusting parameters in the previous procedure;

and 4, step 4: uniformly coating the graphene ink on the coating layer of the white board paper base through a coating machine to form a graphene precoating layer; and drying;

and 5: preparing a porous structure on the graphene precoat; and drying;

step 6: continuously coating a layer of graphene printing ink on the graphene precoat in the step 5; and dried.

Preferably, the method for preparing the porous structure in the step 5 is to spray a layer of etching agent on the graphene pre-coating layer; after staying for 10-15S, passing through a roughing roller to remove the residual etching agent on the graphene precoating layer; thereby forming a porous structure uniformly distributed on the graphene precoat.

Preferably, the method for detecting the surface property of the base paper and judging the surface flatness of the base paper in the step 3 comprises the following substeps:

s1, taking the standard sample paper base, irradiating with a standard light source;

s2, shooting a surface character image of the sample paper base through a high-definition camera device; extracting the edge of the sample paper base and converting the edge into a standard gray value image;

s3, under the premise of irradiation of the same standard light source; acquiring a surface character image of an actual paper base through an online camera device; extracting the actual paper base edge and converting the actual paper base edge into an actual gray value image; establishing a position coordinate system on the actual gray value image; taking one end point of the actual gray value image as a reference point, and taking the width direction of the actual gray value image as an X axis; taking the length direction of the actual gray value image as a Y axis;

s4, corresponding the actual gray value image and the standard gray value image to a coordinate system one by one;

s5 selecting a pixel of the actual gray image with a gray value of G₀The average gray value G of the standard gray value image is compared with the average gray value G of the standard gray value image_tComparing, if the obtained difference absolute value G_nIf the gray value is less than or equal to 5, taking the changed point as the gray value of the pixel of the reference point, and performing difference comparison operation on the gray value of the pixel of the adjacent point and the gray value of the pixel of the reference point to obtain a difference absolute value T1; and recording the comparison quantity as S1; if T1 is less than or equal to 10; recording the gray value of the adjacent point; if T1 is more than 10, discarding the gray value of the adjacent point; repeating the steps until all the pixel points with the difference absolute value less than or equal to 10 are found; and adjusting the gray value of the pixel points to the average gray value G_tThe same; if G is obtained for the first time_nIs more than 5; then look again until G is found_nA point no more than 5;

s6, carrying out AND operation on the actual gray value image and the standard gray value image to obtain pixel points which are different from the standard gray value image in the actual gray value image; simultaneously obtaining the gray value after the AND operation;

s7, marking the outer contour of each abnormal area; and determining a coordinate region of the abnormal region: thereby obtaining the actual position of the abnormal occurrence; the process parameters can be conveniently adjusted in the actual production line subsequently; the method for determining the coordinate area comprises the following steps: taking the outermost edge points of the upper, lower, left and right sides of the abnormal area as tangent points, making a tangent line, and determining the range occupied by the abnormal area by using coordinates of the tangent line;

s8, judging whether the abnormal area is concave or convex; the central point of the abnormal area is taken as the center of a circle and is radiated outwards in a circle; marking pixel points with the gray value larger than 0 and smaller than 0 after the AND operation respectively; determining that the area formed by the pixel points with the gray value greater than 0 after the AND operation is sunken; and judging the area formed by the pixel points with the gray value less than 0 after the AND operation as the bulge.

Preferably, the preparation method of the precoated graphene ink comprises the following steps:

(a) taking solid graphene oxide; heating solid graphene oxide in an environment of: heating to 1000-1300 ℃ at the speed of 80-200 ℃/min; lasting for 20min-35min, and rapidly cooling;

(b) dispersing the solid graphene oxide subjected to rapid freezing by using an ultrasonic instrument to obtain nano graphene oxide powder;

(c) adding nano graphene oxide powder into the resin slurry; adding a dispersing agent and an auxiliary agent while fully stirring to prepare the pre-coated graphene ink; wherein the mass percent of the nano graphene oxide powder is 25-35%.

Wherein the dispersion time of the ultrasonic instrument is 0.9-1.5H.

Preferably, in the step (a), the temperature is rapidly reduced to 140-280 ℃ below zero in 10-25s under an inert gas environment.

Preferably, the preparation method of the surface graphene ink comprises the following steps:

(d) taking solid graphene oxide; heating solid graphene oxide in an environment of: heating to 1000-1300 ℃ at the speed of 80-200 ℃/min; lasting for 20min-35min, and rapidly cooling;

(e) dispersing the solid graphene oxide subjected to rapid freezing by using an ultrasonic instrument to obtain nano graphene oxide powder;

(f) fully mixing nano graphene oxide powder and titanium dioxide, and adding the mixture into resin slurry; adding a dispersing agent and an auxiliary agent while fully stirring to prepare the pre-coated graphene ink; wherein the mass percent of the nano graphene oxide powder is 6-15%.

Compared with the prior art, the invention has the beneficial effects that:

the invention provides a method for coating high-saturation graphene ink on white board paper, which is used for detecting the surface shape of a paper base in real time during printing so as to ensure that the ink has a good attachment base; secondly, combining the coatings of each layer in a multi-coating mode to form a porous structure; the thickness of the interlayer is obviously reduced due to the multi-layer coating, the adhesive force is enhanced, and the coatings of all layers are combined more firmly by matching with the porous structure; thereby preparing the high-quality graphene specialty paper.

Detailed Description

The technical solutions in the embodiments of the present invention are clearly and completely described below, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Example 1

The invention provides a technical scheme that:

the coating method of the high-saturation graphene ink on the white board paper comprises the following steps:

step 1: preparation of pre-coated graphene ink and surface graphene ink:

step 2: preparing a white board paper base; and finishing the coating; the thickness of the coating layer is 0.01-0.03 mm;

and step 3: detecting the surface properties of the white board paper base in the step 2, and judging the surface flatness of the paper base; if the surface is uneven, adjusting parameters in the previous procedure;

and 4, step 4: uniformly coating the graphene ink on the coating layer of the white board paper base through a coating machine to form a graphene precoating layer; and drying;

and 5: preparing a porous structure on the graphene precoat; and drying;

step 6: continuously coating a layer of graphene printing ink on the graphene precoat in the step 5; and dried.

The method for preparing the porous structure in the step 5 is to spray a layer of etching agent on the graphene precoat; after staying for 10-15S, passing through a roughing roller to remove the residual etching agent on the graphene precoating layer; thereby forming a porous structure uniformly distributed on the graphene precoat. The etching agent adopts sodium hydroxide solution, and is sprayed on the precoating layer in an atomization mode; the periphery of the atomization device is protected by a partition plate;

the method for detecting the surface property of the base paper and judging the surface evenness of the base paper in the step 3 comprises the following substeps:

s1, taking the standard sample paper base, irradiating with a standard light source;

s2, shooting a surface character image of the sample paper base through a high-definition camera device; extracting the edge of the sample paper base and converting the edge into a standard gray value image;

s3, under the premise of irradiation of the same standard light source; acquiring a surface character image of an actual paper base through an online camera device; extracting the actual paper base edge and converting the actual paper base edge into an actual gray value image; establishing a position coordinate system on the actual gray value image; taking one end point of the actual gray value image as a reference point, and taking the width direction of the actual gray value image as an X axis; taking the length direction of the actual gray value image as a Y axis;

s4, corresponding the actual gray value image and the standard gray value image to a coordinate system one by one;

s5 selecting a pixel of the actual gray image with a gray value of G₀The average gray value G of the standard gray value image is compared with the average gray value G of the standard gray value image_tComparing, if the obtained difference absolute value G_nIf the gray value is less than or equal to 5, taking the changed point as the gray value of the pixel of the reference point, and performing difference comparison operation on the gray value of the pixel of the adjacent point and the gray value of the pixel of the reference point to obtain a difference absolute value T1; and recording the comparison quantity as S1; if T1 is less than or equal to 10; recording the gray value of the adjacent point; if T1 is more than 10, discarding the gray value of the adjacent point; repeating the steps until all the pixel points with the difference absolute value less than or equal to 10 are found; and adjusting the gray value of the pixel points to the average gray value G_tThe same; if G is obtained for the first time_nIs more than 5; then look again until G is found_nA point no more than 5;

s6, carrying out AND operation on the actual gray value image and the standard gray value image to obtain pixel points which are different from the standard gray value image in the actual gray value image; simultaneously obtaining the gray value after the AND operation;

s7, marking the outer contour of each abnormal area; and determining a coordinate region of the abnormal region: thereby obtaining the actual position of the abnormal occurrence; the process parameters can be conveniently adjusted in the actual production line subsequently; the method for determining the coordinate area comprises the following steps: taking the outermost edge points of the upper, lower, left and right sides of the abnormal area as tangent points, making a tangent line, and determining the range occupied by the abnormal area by using coordinates of the tangent line;

s8, judging whether the abnormal area is concave or convex; the central point of the abnormal area is taken as the center of a circle and is radiated outwards in a circle; marking pixel points with the gray value larger than 0 and smaller than 0 after the AND operation respectively; determining that the area formed by the pixel points with the gray value greater than 0 after the AND operation is sunken; and judging the area formed by the pixel points with the gray value less than 0 after the AND operation as the bulge.

The preparation method of the pre-coated graphene ink comprises the following steps:

(a) taking solid graphene oxide; heating solid graphene oxide in an environment of: heating to 1000-1300 ℃ at the speed of 80-200 ℃/min; lasting for 20min-35min, and rapidly cooling;

(b) dispersing the solid graphene oxide subjected to rapid freezing by using an ultrasonic instrument to obtain nano graphene oxide powder;

(c) adding nano graphene oxide powder into the resin slurry; adding a dispersing agent and an auxiliary agent while fully stirring to prepare the pre-coated graphene ink; wherein the mass percent of the nano graphene oxide powder is 25-35%.

Wherein the dispersion time of the ultrasonic instrument is 0.9-1.5H.

Preferably, in the step (a), the temperature is rapidly reduced to 140-280 ℃ below zero in 10-25s under an inert gas environment. The preparation method of the surface graphene ink comprises the following steps:

(d) taking solid graphene oxide; heating solid graphene oxide in an environment of: heating to 1000-1300 ℃ at the speed of 80-200 ℃/min; lasting for 20min-35min, and rapidly cooling;

(e) dispersing the solid graphene oxide subjected to rapid freezing by using an ultrasonic instrument to obtain nano graphene oxide powder;

(f) fully mixing nano graphene oxide powder and titanium dioxide, and adding the mixture into resin slurry; adding a dispersing agent and an auxiliary agent while fully stirring to prepare the pre-coated graphene ink; wherein the mass percent of the nano graphene oxide powder is 6-15%.

The preparation method of the solid graphene oxide comprises the following steps:

mixing natural graphite and sodium nitrate uniformly, adding concentrated sulfuric acid, stirring for 10-150 min, then adding potassium permanganate, and continuing stirring for 10-150 min to obtain a mixed solution;

transferring the mixed solution into a constant-temperature water bath at the temperature of 20-40 ℃, and stirring for reaction for 15-180 min; adding deionized water into the mixed solution, reacting for 30-60 min, then raising the temperature of the constant-temperature water bath at 20-40 ℃ to 80-100 ℃, and stirring for 30-300 min; and finally, adding hydrogen peroxide, reacting for 30-90 min, washing and drying to obtain the graphene oxide.

Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.