Matt synergy method for digital printing gloss oil

Abstract

The invention discloses a matt synergistic method for digital printing gloss oil. The matt synergistic method comprises the following steps: step a) preparing raw materials; b) stirring; c) coating; step d) drying; e) humidifying: a) preparing raw materials: preparing a proper amount of UV ink, a diluent, white oil, a viscosity reducer and an inorganic filler, b) stirring: stirring and mixing the raw materials in the step a) to form high-gloss ink, c) coating: uniformly coating the ink on the coated surface through a printing machine to form a gloss oil first layer, and d) drying the gloss oil first layer. The drying efficiency of the first gloss oil layer and the second gloss oil layer is controlled through irradiation and sunlight irradiation, when the ink is cured to form a film, the inorganic material is free and floats on the surface of the cured ink film by utilizing the incompatibility between a resin system and the inorganic material, the glossiness of the ink film is reduced, and a matte effect is achieved.

Description

Technical Field

[0001] The invention relates to the technical field of digital printing, in particular to a method for enhancing the matte effect of digital printing varnish. Background Art

[0002] Digital printing is the digitization of printing technology. It refers to the partial or complete digitization of the whole process. For example: laser typesetting, remote plate transmission, digital proofing, computer direct platemaking, digital workflow, printing factory ERP, etc. all belong to the category of digital printing. Inkjet printing is a kind of non-contact, pressure-free, and plate-free printing. The information stored in the computer can be input into the inkjet printer for printing. The inkjet printer consists of a system controller, an inkjet controller, a nozzle, a substrate drive mechanism, etc. Under the control of the inkjet controller, the ink is sprayed from the nozzle of the nozzle and printed on the substrate. According to the printing requirements, the driver transports the substrate, and the system controller is responsible for the operation of the whole machine.

[0003] However, the existing matte printing must be formed with matte ink. The powder particles of matte ink are larger, and its printing speed may be relatively slow compared with other inks. This may affect production efficiency. The ink powder is easy to form oil marks on the paper during the printing process, which is not suitable for all types of printing materials.

[0004] Therefore, it is necessary to design and create a method to enhance the matte effect of digital printing varnish. Summary of the invention

[0005] In order to solve the problems raised in the above background technology, the purpose of the present invention is to provide a digital printing varnish matte enhancement method, which has the advantages of varnish matte printing and solves the problem that the existing matte printing must increase the matte ink for molding, and the powder particles of the matte ink are larger, and the printing speed may be relatively slow compared with other inks. This may affect the production efficiency, and the ink powder is easy to form oil marks on the paper during the printing process, and is not suitable for all types of printing materials.

[0006] To achieve the above object, the present invention provides the following technical solution: a method for enhancing the matte effect of digital printing varnish, comprising the following steps: step a) preparing raw materials; step b) stirring; step c) coating; step d) drying; step e) humidifying: Step a) Prepare raw materials: prepare appropriate amount of UV ink, diluent, white oil, detackifier, and inorganic filler; Step b) stirring: stirring and mixing the raw materials in step a) to form a high gloss ink; Step c) coating: the ink is evenly applied to the coating surface by a printing machine to form a first layer of varnish; Step e) Humidification: During the drying process of the first layer of varnish, a humidifier is used to increase the ambient humidity and reduce the coating drying speed; Step d) secondary coating: after the first layer of varnish is dried, the raw material is stirred in step b) for secondary coating to form a second layer of varnish; Step d) Irradiation: After the secondary coating is completed, the second varnish layer is irradiated with a light source of a longer wavelength to basically cure the ink in the lower layer of the second varnish layer. Although the light energy of the surface layer of the ink layer is relatively strong, it is interfered by oxygen inhibition, and the upper surface layer is poorly cured, forming a structure of dense bottom and sparse top in the ink layer, forcing the inorganic filler inside the UV ink to utilize its incomplete solubility with the organic cross-linking network to migrate to the surface layer with poor curing condition and gather on the surface of the ink layer. Then, the ink layer is irradiated with a light source of a shorter wavelength and higher energy to completely cure the surface layer of the ink, thereby obtaining a matte coating through digital printing varnish.

[0007] As a preferred embodiment of the present invention, the raw materials are prepared in step a), and the contents of the components are 0.2 parts of diluent, 0.3 parts of white oil, 0.1 parts of detackifier, 0.5 parts of inorganic filler for every 10 parts of digital printing varnish, and the content is supplemented with 10 parts of UV ink.

[0008] As a preferred embodiment of the present invention, the step b) stirring: the ink is fully stirred by a shear stirring device to ensure that the viscosity of the varnish is uniform and the inorganic filler is evenly distributed inside the high gloss ink.

[0009] As a preferred embodiment of the present invention, in the step c) coating, the pressure of the printing machine is 0.6-0.8 MPa, and the printing speed is 9000-10000 sheets / hour.

[0010] As a preferred embodiment of the present invention, the step e) humidification: during the drying process of the first layer of varnish, a humidifier is arranged around the coating to keep the ambient humidity at 50-70%. Excessive humidity can hinder the evaporation of solvents and water in the ink, slow down the drying speed of the ink, and improve the matte effect of the ink.

[0011] As a preferred embodiment of the present invention, the step d) of secondary coating is as follows: firstly, the dried first varnish layer is wiped and cleaned to reduce the amount of dust on the surface of the first varnish layer and to moisten the first varnish layer to facilitate the combination of the first varnish layer and the second varnish layer.

[0012] As a preferred embodiment of the present invention, the step d) irradiation: during the irradiation process, the coating should be kept inside the sealed space to reduce the contact area between the external environment and the coating, and at the same time, the airflow inside the closed space is extracted by utilizing the principle of negative pressure adsorption to accelerate the flow of the airflow, reduce the temperature inside the sealed space, increase the drying time of the ink, reduce the bonding effect of components such as pigments and resins in the ink, and form a matte ink film on its surface.

[0013] As a preferred embodiment of the present invention, the step c) coating: during the open-air coating process, the airflow around the coating is diffused to the outside by positive pressure to prevent external dust from falling onto the coated surface. At the same time, the positive pressure can increase the water vapor diffusion rate, so that the coating is in uniform contact with moisture.

[0014] Compared with the prior art, the present invention has the following beneficial effects: 1. The present invention controls the drying efficiency of the first and second varnish layers by means of radiation irradiation. When the ink is cured into a film, the incompatibility between the resin system and the inorganic material can be used to make the inorganic material free and float on the surface of the cured ink film, thereby reducing the glossiness of the ink film and forming a matte effect.

[0015] 2. The present invention reduces the drying temperature by increasing the air flow rate. The slower drying time can reduce the evaporation rate of the solvent and water in the ink, so that the pigment, resin and other components in the ink are quickly separated to form a rough ink film, thereby achieving the effect of improving the matte degree of the printed product.

[0016] 3. The present invention can further hinder the evaporation of solvent and water in the ink by increasing the humidity of the drying environment during the drying process, causing the ink drying speed to slow down. At the same time, it can increase the wettability of the ink film and avoid cracking of the ink film during the drying process.

[0017] 4. The present invention can accelerate the formation of ink film by increasing the pressure and printing speed of the printing equipment. Excessive compaction of the ink can reduce the glossiness of the printed matter and achieve a matte effect.

[0018] 5. The present invention can inhibit the drying of ink by adding diluent, white oil, detackifier and inorganic filler into the ink, which will slow down the drying of the print, thereby affecting the glossiness of the printed matter and achieving a matte effect. DETAILED DESCRIPTION

[0019] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. 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.

[0020] The present invention provides a method for enhancing the matte effect of digital printing varnish, comprising the following steps: step a) preparing raw materials; step b) stirring; step c) coating; step d) drying; and step e) humidifying: Step a) Prepare raw materials: prepare appropriate amount of UV ink, diluent, white oil, detackifier, and inorganic filler; Step b) stirring: stirring and mixing the raw materials in step a) to form a high gloss ink; Step c) coating: the ink is evenly applied to the coating surface by a printing machine to form a first layer of varnish; Step e) Humidification: During the drying process of the first layer of varnish, a humidifier is used to increase the ambient humidity and reduce the coating drying speed; Step d) secondary coating: after the first layer of varnish is dried, the raw material is stirred in step b) for secondary coating to form a second layer of varnish; Step d) Irradiation: After the secondary coating is completed, the second varnish layer is irradiated with a light source of a longer wavelength to basically cure the ink in the lower layer of the second varnish layer. Although the light energy of the surface layer of the ink layer is relatively strong, it is interfered by oxygen inhibition, and the upper surface layer is poorly cured, forming a structure of dense bottom and sparse top in the ink layer, forcing the inorganic filler inside the UV ink to utilize its incomplete solubility with the organic cross-linking network to migrate to the surface layer with poor curing condition and gather on the surface of the ink layer. Then, the ink layer is irradiated with a light source of a shorter wavelength and higher energy to completely cure the surface layer of the ink, thereby obtaining a matte coating through digital printing varnish.

[0021] As a technical optimization scheme of the present invention, the raw materials are prepared through step a), and the content of each component is 0.2 parts of diluent, 0.3 parts of white oil, 0.1 parts of detackifier, 0.5 parts of inorganic filler for every 10 parts of digital printing varnish, and 10 parts are supplemented with UV ink.

[0022] As a technical optimization solution of the present invention, through step b) stirring: the ink is fully stirred by a shear stirring device to ensure that the consistency of the varnish is uniform and the inorganic filler is evenly distributed inside the high gloss ink.

[0023] As a technical optimization solution of the present invention, through step c) coating: the pressure of the printing machine is 0.6-0.8 MPa, and the printing speed is 9000-10000 sheets / hour.

[0024] As a technical optimization scheme of the present invention, through step e) humidification: during the drying process of the first layer of varnish, a humidifier is set around the coating to keep the ambient humidity at 50-70%. Excessive humidity can hinder the evaporation of solvents and water in the ink, slow down the drying speed of the ink, and improve the matte effect of the ink.

[0025] As a technical optimization scheme of the present invention, through step d) secondary coating: first wipe and clean the dried first layer of varnish to reduce the amount of dust on the surface of the first layer of varnish, and at the same time make the first layer of varnish moist to facilitate the combination of the first layer of varnish and the second layer of varnish.

[0026] As a technical optimization scheme of the present invention, through step d) irradiation: during the irradiation process, the coating should be kept inside the sealed space to reduce the contact area between the external environment and the coating. At the same time, the airflow inside the closed space is extracted by utilizing the principle of negative pressure adsorption to accelerate the flow of the airflow, reduce the temperature inside the sealed space, increase the drying time of the ink, reduce the binding effect of components such as pigments and resins in the ink, and form a matte ink film on its surface.

[0027] As a technical optimization scheme of the present invention, through step c) coating: during the open-air coating process, the air flow around the coating is diffused to the outside by positive pressure to prevent external dust from falling onto the coated surface. At the same time, the positive pressure can increase the water vapor diffusion rate, so that the coating is in uniform contact with moisture.

[0028] The working principle and use process of the present invention are as follows: prepare appropriate amount of UV ink, diluent, white oil, detackifier and inorganic filler, stir and mix the raw materials in step a) to form high gloss ink, apply the ink evenly on the surface of the coating by a printing machine, and then place the coated coating in an open-air dry place to allow it to dry naturally by sunlight to form a first layer of varnish. During the drying process of the first layer of varnish, a humidifier is used to increase the ambient humidity and reduce the coating drying speed. After the first layer of varnish is dried, the raw materials are stirred in step b) for secondary coating to form a high gloss ink. After the second coating is completed, the second layer of varnish is irradiated with a light source with a longer wavelength to basically solidify the ink under the second layer of varnish. Although the light energy of the surface layer of the ink layer is relatively strong, it is interfered by oxygen inhibition, and the upper surface layer is poorly cured, forming a dense bottom and sparse top structure in the ink layer, forcing the inorganic filler inside the UV ink to utilize its incomplete solubility with the organic cross-linking network to migrate to the surface layer with poor curing condition and gather on the surface of the ink layer. Then, the ink layer is irradiated with a light source with a shorter wavelength and higher energy to completely solidify the surface layer of the ink, thereby obtaining a matte coating through digital printing varnish.

[0029] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0030] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for enhancing the matte effect of digital printing varnish, characterized in that: The method comprises the following steps: step a) preparing raw materials; step b) stirring; step c) coating; step d) drying; and step e) humidifying. Step a) Prepare raw materials: prepare appropriate amount of UV ink, diluent, white oil, detackifier, and inorganic filler; Step b) stirring: stirring and mixing the raw materials in step a) to form a high gloss ink; Step c) coating: the ink is evenly applied to the coating surface by a printing machine to form a first layer of varnish; Step e) Humidification: During the drying process of the first layer of varnish, a humidifier is used to increase the ambient humidity and reduce the coating drying speed; Step d) secondary coating: after the first layer of varnish is dried, the raw material is stirred in step b) for secondary coating to form a second layer of varnish; Step d) Irradiation: After the secondary coating is completed, the second varnish layer is irradiated with a light source of a longer wavelength to basically cure the ink in the lower layer of the second varnish layer. Although the light energy of the surface layer of the ink layer is relatively strong, it is interfered by oxygen inhibition, and the upper surface layer is poorly cured, forming a structure of dense bottom and sparse top in the ink layer, forcing the inorganic filler inside the UV ink to utilize its incomplete solubility with the organic cross-linking network to migrate to the surface layer with poor curing condition and gather on the surface of the ink layer. Then, the ink layer is irradiated with a light source of a shorter wavelength and higher energy to completely cure the surface layer of the ink, thereby obtaining a matte coating through digital printing varnish.

2. A method for enhancing the matte finish of digital printing varnish according to claim 1, characterized in that: In the step a), raw materials are prepared. For every 10 parts of digital printing varnish, the content of each component is 0.2 parts of diluent, 0.3 parts of white oil, 0.1 parts of detackifier, 0.5 parts of inorganic filler, and the content is supplemented with 10 parts of UV ink.

3. A method for enhancing the matte effect of digital printing varnish according to claim 1, characterized in that: The step b) stirring: the ink is fully stirred by a shear stirring device to ensure that the consistency of the varnish is uniform and the inorganic filler is evenly distributed inside the high gloss ink.

4. A method for enhancing the matte effect of digital printing varnish according to claim 1, characterized in that: The step c) coating: the pressure of the printing machine is 0.6-0.8 MPa, and the printing speed is 9000-10000 sheets / hour.

5. The method for enhancing the matte effect of digital printing varnish according to claim 1, characterized in that: Step e) Humidification: During the drying process of the first layer of varnish, a humidifier is arranged around the coating to keep the ambient humidity at 50-70%. Excessive humidity can hinder the evaporation of solvents and water in the ink, slow down the drying speed of the ink, and improve the matte effect of the ink.

6. A method for enhancing the matte effect of digital printing varnish according to claim 1, characterized in that: The step d) secondary coating: firstly, the dried first varnish layer is wiped and cleaned to reduce the amount of dust on the surface of the first varnish layer and to moisten the first varnish layer to facilitate the combination of the first varnish layer and the second varnish layer.

7. A method for enhancing the matte effect of digital printing varnish according to claim 1, characterized in that: The step d) irradiation: during the irradiation process, the coating should be kept inside the sealed space to reduce the contact area between the external environment and the coating. At the same time, the airflow inside the closed space is extracted by using the principle of negative pressure adsorption to accelerate the flow of the airflow, reduce the temperature inside the sealed space, increase the drying time of the ink, reduce the binding effect of components such as pigments and resins in the ink, and form a matte ink film on the surface.

8. The method for enhancing the matte effect of digital printing varnish according to claim 1, characterized in that: Step c) coating: During the open-air coating process, positive pressure is used to diffuse the airflow around the coating to the outside, thereby preventing external dust from falling onto the coated surface. At the same time, positive pressure can increase the diffusion rate of water vapor, so that the coating is in uniform contact with moisture.