阅读说明：本技术 一种对金属基材表面丝印磨砂的方法 (Method for conducting screen printing and frosting on surface of metal base material ) 是由 朱清成 阳名利 于 2019-10-28 设计创作，主要内容包括：本发明涉及金属基材丝印技术领域,具体涉及一种对金属基材表面丝印磨砂的方法,包括如下步骤：1)先将金属基材切割加工成金属基材面板,打磨、清洗烘干,备用；2)对步骤1)中处理后的金属基材面板进行导电氧化处理；3)使用改性油墨对步骤2)中处理后的金属基材面板正面采用丝印方法进行丝印,丝印后进行烘烤；4)使用UV油墨对对步骤3)中处理后的金属基材背面板进行丝印,再将金属基材面板放入UV固化装置内进行固化处理。本发明中使用改性油墨对面板进行网板丝印,烘干后进行套色印刷,使用丝印工艺使面板表面达到面膜的细腻磨砂效果,拥有类似于面膜的高档外观,同时可以提高防火性、环境适应性,可使用在严苛复杂的环境中。(The invention relates to the technical field of metal substrate silk-screen printing, in particular to a method for frosting the surface of a metal substrate by silk-screen printing, which comprises the following steps: 1) firstly, cutting a metal base material into a metal base material panel, polishing, cleaning and drying for later use; 2) conducting conductive oxidation treatment on the metal substrate panel treated in the step 1); 3) silk-screen printing is carried out on the front surface of the metal substrate panel treated in the step 2) by using modified ink by a silk-screen printing method, and baking is carried out after silk-screen printing; 4) and 3) carrying out silk-screen printing on the metal substrate back panel treated in the step 3) by using UV ink, and then putting the metal substrate panel into a UV curing device for curing treatment. The modified ink is used for screen printing of the screen plate of the panel, the panel is subjected to color register printing after being dried, and the screen printing process is used for enabling the surface of the panel to achieve the fine and smooth frosting effect of the mask, so that the panel has high-grade appearance similar to the mask, meanwhile, the fire resistance and the environmental adaptability can be improved, and the panel can be used in a severe and complex environment.)

1. A method for carrying out screen printing and frosting on the surface of a metal base material is characterized by comprising the following steps: the method comprises the following steps:

1) cutting and processing the metal base material on a numerical control machine tool into a metal base material panel, polishing, cleaning and drying for later use;

2) conducting conductive oxidation treatment on the metal substrate panel treated in the step 1);

3) silk-screen printing is carried out on the front surface of the metal substrate panel treated in the step 2) by using modified ink by a silk-screen printing method, and baking is carried out after silk-screen printing;

4) and 3) carrying out silk-screen printing on the metal substrate back panel treated in the step 3) by using UV ink according to the designed pattern, and after the silk-screen printing is finished, putting the metal substrate panel into a UV curing device for curing treatment to finally obtain a finished product.

2. The method of claim 1, wherein the step of screen-printing and sanding the surface of the metal substrate comprises the steps of: each part of the modified ink comprises the following raw materials in parts by weight:

3. the method for screen-printing and frosting the surface of the metal substrate according to claim 2, wherein the method comprises the following steps: each part of the curing agent is at least one of phenolsulfonic acid, ethylene oxide and methyl tetrahydrophthalic anhydride.

4. A method of screen-sanding a surface of a metal substrate according to any one of claims 2-3, wherein: the modified ink is prepared by the following method:

a1, adding the acrylic resin modified dispersion and maleic resin into ethyl acetate and isophorone according to parts by weight, uniformly stirring, heating to 40-60 ℃, and keeping the temperature for 30-60min to obtain a mixture A for later use;

a2, mixing and stirring the silver white pearl powder and the silver powder uniformly, transferring and adding the mixture into the four-primary-color ink, and stirring at the speed of 800-;

a3, dripping the mixture A obtained in the step A1 into the mixture B obtained in the step A2 at the speed of 5-10mL/min while stirring, heating to 60-80 ℃ after dripping, adding a curing agent, stirring at the speed of 500-700r/min for 10-20min, and standing to obtain the modified ink.

5. The method of claim 1, wherein the step of screen-printing and sanding the surface of the metal substrate comprises the steps of: in the step 2), the voltage during oxidation treatment is 8-15V, and the electrifying oxidation time is 20-40 min.

6. The method of claim 1, wherein the step of screen-printing and sanding the surface of the metal substrate comprises the steps of: in the step 3), the temperature during baking is 120-160 ℃, and the baking time is 30-50 min.

7. The method of claim 1, wherein the step of screen-printing and sanding the surface of the metal substrate comprises the steps of: each part of the UV printing ink comprises the following raw materials in parts by weight:

8. the method of claim 7, wherein the step of screen-printing and sanding the surface of the metal substrate comprises the steps of: the UV ink is prepared by the following method:

s1, mixing and stirring uniformly vinyl ester resin, propylene carbonate and organic silicon acrylate according to parts by weight, heating to 60-80 ℃, adding 2-isopropyl thioxanthone and stirring for 10-20min to obtain a mixture I for later use;

s2, adding a cupric salt and hydroquinone into the mixture I obtained in the step S1, and stirring at the speed of 400-800r/min for 30-60min to obtain a mixture II for later use;

s3, adding polyethylene wax into the mixture II obtained in the step S2, heating to 70-90 ℃, stirring at the speed of 300-600r/min for 20-40min, and cooling to obtain the UV ink.

9. The method of claim 1, wherein the step of screen-printing and sanding the surface of the metal substrate comprises the steps of: in step 4), spectrum of the curing deviceThe wavelength is 300-420nm, and the power of the UV lamp is 70-90W/cm²The slide speed of the curing device is 10-15 m/min.

Technical Field

The invention relates to the technical field of metal substrate silk-screen printing, in particular to a method for frosting the surface of a metal substrate through silk-screen printing.

Background

With the wide application and continuous development of the anodic oxidation process of the aluminum alloy, in order to increase the decorative effect of the appearance of the aluminum alloy product, the surface of the aluminum alloy is generally subjected to comprehensive treatment by adopting a screen printing process, and particularly, the product subjected to screen printing and frosting printing has an obvious etching effect, is strong in three-dimensional sense, gives people a thick, solid and heavy feeling, and is very prominent in texture. Regarding the printing of the silk-screen frosting, the printing is applied to the printing and packaging industry for a long time, and the existing silk-screen frosting printing has the following problems: at present, the requirement of the printing industry on sanitation and safety indexes such as the limit of Volatile Organic Compounds (VOCS), formaldehyde, heavy metals and photoinitiators is more and more strict, and the overproof of the photoinitiators can be caused by volatile harmful gas generated by using UV ink in the process of screen printing and frosting printing. The UV frosted ink for silk screen printing has poor adhesive force and flexibility, is easy to explode and burst during die cutting, and the comprehensive performance of the product is greatly influenced

Disclosure of Invention

In order to overcome the defects and shortcomings in the prior art, the invention aims to provide a method for screen printing and frosting the surface of a metal substrate.

The purpose of the invention is realized by the following technical scheme: a method for carrying out screen printing and frosting on the surface of a metal base material comprises the following steps:

1) cutting and processing the metal base material on a numerical control machine tool into a metal base material panel, polishing, cleaning and drying for later use;

2) conducting conductive oxidation treatment on the metal substrate panel treated in the step 1);

3) silk-screen printing is carried out on the front surface of the metal substrate panel treated in the step 2) by using modified ink by a silk-screen printing method, and baking is carried out after silk-screen printing;

4) and 3) carrying out silk-screen printing on the metal substrate back panel treated in the step 3) by using UV ink according to the designed pattern, and after the silk-screen printing is finished, putting the metal substrate panel into a UV curing device for curing treatment to finally obtain a finished product.

The screen printing and frosting method of the invention uses the modified ink to screen the panel, and carries out chromatography printing after drying, and uses the screen printing process to make the surface of the panel achieve the fine frosting effect of the mask, so that the mask has high-grade appearance similar to the mask, and meanwhile, the fireproof performance and the environmental adaptability can be improved, and the mask can be used in harsh and complex environments. In the steps 2) and 3), the conductive oxidation treatment and the silk-screen frosted printing are combined, so that the product has an obvious etching effect and strong stereoscopic impression, gives people a thick, firm and heavy feeling, and is very prominent in texture; the modified ink adopted in the silk-screen printing process has the characteristics of strong adhesive force and flexibility, has the function of preventing explosion color bursting during die cutting, and also has good printing leveling property, frosted blooming effect and toughness.

Preferably, each part of the modified ink comprises the following raw materials in parts by weight:

each part of the curing agent is at least one of phenolsulfonic acid, ethylene oxide and methyl tetrahydrophthalic anhydride, and more preferably, the curing agent is a mixture of phenolsulfonic acid, ethylene oxide and methyl tetrahydrophthalic anhydride according to the weight ratio of 0.4-0.8:0.6-1.0: 0.8-1.2;

more preferably, the acrylic resin modified dispersion is an HH-201 series acrylic resin modified dispersion manufactured by Xiamenhe Co., Ltd; the type of the four-primary-color ink is four-primary-color ink RS 900.

The HH-201 acrylic resin modified dispersion adopted in the raw materials of the modified ink has good bottom sealing performance, can improve the hardness and density of a substrate, and is beneficial to assisting in improving the film forming performance of the prepared modified ink; the four-primary-color ink RS900 is low in toxicity, free of peculiar smell, non-combustible, non-explosive, bright in color, high in color strength, rapid in drying, good in luster, stable in ink quality, convenient to clean, and good in light resistance, heat resistance and sun resistance; the adopted maleic acid resin has the advantages of high brightness, high hardness, strong adhesive force and the like, and can further compositely enhance the adhesive force and the glossiness of the prepared modified ink; isophorone can be used as a diluent to well dissolve maleic resin and acrylic resin modified dispersoid; the silver white pearl powder is a pearlescent pigment capable of generating pearl luster, is transparent and flat powder in appearance, has elegant luster, has an average effective refractive index of 2.5, has higher heat resistance (900 ℃) and higher weather resistance, can enhance the chemical structure of the modified ink to ensure that the modified ink has excellent dispersion and heat resistance, and the silver powder can further assist the silver white pearl powder to improve the weather resistance and the high temperature resistance of the modified ink; in addition, the methyl tetrahydrophthalic anhydride adopted in the curing agent is used for curing the acrylic resin modified dispersoid and the maleic resin, has excellent performances of long-term storage at room temperature, low freezing point, small volatility, low toxicity and the like, and can assist the advantages of phenol sulfonic acid and ethylene oxide to further improve the curing performance of the modified ink.

Preferably, the modified ink is prepared by the following method:

a1, adding the acrylic resin modified dispersion and maleic resin into ethyl acetate and isophorone according to parts by weight, uniformly stirring, heating to 40-60 ℃, and keeping the temperature for 30-60min to obtain a mixture A for later use;

a2, mixing and stirring the silver white pearl powder and the silver powder uniformly, transferring and adding the mixture into the four-primary-color ink, and stirring at the speed of 800-;

a3, dripping the mixture A obtained in the step A1 into the mixture B obtained in the step A2 at the speed of 5-10mL/min while stirring, heating to 60-80 ℃ after dripping, adding a curing agent, stirring at the speed of 500-700r/min for 10-20min, and standing to obtain the modified ink.

The modified ink prepared by the method has the characteristics of strong adhesive force and flexibility, has an explosion-proof color burst function during die cutting, and also has good printing leveling property, frosted blooming effect and toughness; in addition, the stirring speed in the step A2 needs to be controlled to be 800-1200r/min in the preparation process, if the stirring speed is too high, the silver white pearl powder and the silver powder are wrapped into microcapsules which are difficult to disperse in the four-primary-color ink, and if the stirring speed is too high, the silver white pearl powder and the silver powder mixed powder are also not used to disperse in the four-primary-color ink, so that the weather resistance and the high temperature resistance of the prepared modified ink are not improved; in the step A3, the dropping rate of the mixture A needs to be strictly controlled to be 5-10mL/min, if the dropping rate is too high, the mixture A and the mixture B can be fully dispersed, the adhesion and flexibility of the prepared modified ink can not be improved, and if the dropping rate is too low, the production efficiency can be reduced.

Preferably, in the step 2), the voltage during the oxidation treatment is 8-15V, and the electrifying oxidation time is 20-40 min; in the step 3), the baking temperature is 120-160 ℃, the baking time is 30-50min, and more preferably, in the step 3), the mesh number of the adopted screen plate is 80-100 meshes, the screen printing speed is 50-200mm/s, and the scraper angle is 55-75 degrees; in the step 4), the spectral wavelength of the curing device is 300-420nm, and the power of the UV lamp is 70-90W/cm²The slide speed of the curing device is 10-15 m/min.

According to the invention, the conductive oxidation treatment is carried out on the metal substrate panel, so that the protection capability of aluminum is improved, the metal substrate panel can conduct electricity, the baking temperature is strictly controlled to be 120-160 ℃ when the metal substrate panel is baked after silk-screen printing, the quality of a product after silk-screen printing of the modified ink is poor if the temperature is too high, the product after silk-screen printing is not dried in time and the subsequent silk-screen printing of UV ink is not good if the temperature is too low, the quality of the product is further affected, and the production efficiency is reduced.

Preferably, each part of the UV ink comprises the following raw materials in parts by weight:

the cupric salt is at least one of cupric chloride, ferric nitrate and basic cupric carbonate.

The vinyl ester resin is thermosetting resin, has the excellent characteristics of epoxy resin, is more excellent in curing property and moldability, can be dissolved in polyethylene wax and organic silicon acrylate, and is less in environmental pollution; the propylene carbonate is used as a plasticizer of the UV ink, can also be used as a curing accelerator of the vinyl ester resin, and can be used for enhancing the adhesive force and flexibility of the UV ink in cooperation with the vinyl ester resin; the hydroquinone has a corrosion inhibition effect on water side metal, and the corrosion prevention effect of the prepared UV ink can be further improved; the polyethylene wax has good light resistance and chemical properties, can be used as a carrier of pigment, can improve the wear resistance of ink, improves the dispersibility of cupric salt and organic silicon acrylate, has good anti-settling effect, and can be used as a flatting agent of the ink, so that the prepared UV ink has good gloss and stereoscopic impression; 2-isopropyl thioxanthone is used as a photoinitiator, so that UV printing ink can be initiated to be cured in a curing stage after subsequent screen printing.

Preferably, the UV ink is prepared by the following method:

s1, mixing and stirring uniformly vinyl ester resin, propylene carbonate and organic silicon acrylate according to parts by weight, heating to 60-80 ℃, adding 2-isopropyl thioxanthone and stirring for 10-20min to obtain a mixture I for later use;

s2, adding a cupric salt and hydroquinone into the mixture I obtained in the step S1, and stirring at the speed of 400-800r/min for 30-60min to obtain a mixture II for later use;

s3, adding polyethylene wax into the mixture II obtained in the step S2, heating to 70-90 ℃, stirring at the speed of 300-600r/min for 20-40min, and cooling to obtain the UV ink.

The modified ink is prepared by the method, and the UV ink prepared by the method has the characteristics of strong adhesive force, strong wear resistance and chemical resistance, low toxicity and small pollution, and simultaneously effectively solves the problems of screen printing and pad printing on the existing UV finish paint; in addition, the UV ink provided by the invention simplifies the process of decorating and processing the surface of the UV ink, improves the production efficiency and greatly reduces the defective rate; meanwhile, more various choices are provided for enriching the design of the decoration scheme of the UV ink surface material. In the process of preparing the UV ink, the stirring speed in the step S2 needs to be strictly controlled to be 400-800r/min, if the stirring speed is too fast, the influence of the centrifugal action on the divalent copper salt on dispersion is not uniform, and if the stirring speed is too slow, the divalent copper salt is not favorably and fully diffused into the mixture I, so that the quality of the prepared UV ink is influenced; step S3 requires strict control of the temperature of the polyethylene wax after addition to 70-90 ℃, which would result in partial carbonization of the polyethylene wax if the temperature is too high, and which would not facilitate complete dissolution of the polyethylene wax into mixture ii if the temperature is too low, thereby resulting in degradation of the quality of the finally obtained UV ink.

The invention has the beneficial effects that: the screen printing and frosting method disclosed by the invention is characterized in that the screen printing of the screen plate is carried out on the panel by using the modified ink, the color register printing is carried out after drying, and the screen printing process is used for enabling the surface of the panel to achieve the fine frosting effect of the facial mask, so that the facial mask has high-grade appearance similar to that of the facial mask, meanwhile, the fire resistance and the environmental adaptability can be improved, and the method can be used in a severe and complex environment.

Detailed Description

The present invention will be further described with reference to the following examples for facilitating understanding of those skilled in the art, and the description of the embodiments is not intended to limit the present invention.