Colored drawing process for high-fall, high-color and high-gloss injection molding panel

Abstract

The invention discloses a high-fall, high-color and high-gloss injection molding panel colored drawing process which comprises the following steps: S1, selecting printing ink with a corresponding color, and putting the printing ink into each corresponding ink box in a colored drawing machine; s2, the plastic panel is placed on a colored drawing machine, and ink-jet colored drawing is conducted on the plastic panel through a spray head; s3, UV curing is carried out after colored drawing is completed; the ink is prepared from the following components in parts by weight: 10 to 20 parts of inorganic pigment, 5 to 15 parts of ethyoxyl ethyoxyl ethyl acrylate, 35 to 45 parts of 2-phenoxyl ethyl acrylate, 5 to 15 parts of N-vinyl caprolactam and 1 to 10 parts of dipropylene glycol diacrylate. No volatile organic compound is discharged in the ink, and no VOC is generated when the ink is cured, so that the environmental pollution is greatly reduced; the obtained pattern has good adhesive force, alcohol resistance, light resistance and humidity and heat resistance on a plastic part, and has the characteristic of high fall, and the colored pattern has the characteristics of high color, high gloss and high light transmission, and is more diversified in color.

Description

Technical Field

[0001] The present invention belongs to a painting process, and in particular, relates to a painting process for an injection-molded panel with high drop, high color, and high gloss. Background Art

[0002] When existing plastic parts need to be decorated with different textures or patterns, decorative films are usually directly pasted on the plastic panel, and in some cases, painting is directly carried out on the plastic panel. However, the patterns obtained by directly painting on plastic parts currently are flat, lack a three-dimensional sense, and have insufficient adhesion and alcohol resistance, and the patterns are easy to fall off; when using traditional printing, the VOC components in the ink will continuously volatilize for a long time, causing environmental pollution, having peculiar smells, and having poor light transmittance and unable to achieve patterns at the window position. Summary of the Invention

[0003] The purpose of the present invention is to provide a painting process for an injection-molded panel with high drop, high color, and high gloss that can solve at least one of the above problems.

[0004] According to one aspect of the present invention, there is provided a painting process for an injection-molded panel with high drop, high color, and high gloss, including the following steps:

[0005] S1. Select inks of corresponding colors and place them in respective corresponding ink cartridges in the painting machine;

[0006] S2. Place the plastic panel on the painting machine and perform inkjet painting on the plastic panel through the nozzles of the painting machine;

[0007] S3. Perform UV curing after painting is completed;

[0008] The ink in step S1 is composed of the following components in each weight part:

[0009] 10 - 20 parts of inorganic pigment, 5 - 15 parts of ethoxyethoxyethyl acrylate, 35 - 45 parts of 2-phenoxyethyl acrylate, 5 - 15 parts of N-vinylcaprolactam, and 1 - 10 parts of dipropylene glycol diacrylate.

[0010] In some embodiments, the painting machine in step S1 uses a UV flatbed inkjet printer, there are multiple nozzles, two ink cartridges are installed at each nozzle, a controller is provided on the painting machine, and each ink cartridge is electrically connected to the controller.

[0011] In some embodiments, multiple nozzles are installed at each nozzle, the number of nozzles on each nozzle is 1280, and the size of the ink droplets ejected by the nozzles is 5 - 15 PL.

[0012] In some embodiments, the firing frequency of the nozzles is ≤50 KH.

[0013] In some embodiments, the nozzle can move in the X-axis direction, Y-axis direction, and Z-axis direction on the UV flatbed inkjet printer.

[0014] In some embodiments, the texture resolution after inkjet printing by the nozzle is 600 dpi for monochromatic and 300 dpi for two colors.

[0015] In some embodiments, a UV curing lamp is provided on one side of the nozzle.

[0016] The beneficial effects of the present invention are as follows:

[0017] 1. There is no emission of volatile organic compounds (VOCs) in the painted ink, and no VOCs are generated during the curing process of the ink. Compared with the solvent-based ink used in the traditional printing process, it greatly reduces environmental pollution and also avoids the generation of peculiar smells;

[0018] 2. The pattern obtained by the above ink painting has good adhesion, alcohol resistance, light resistance, and humidity and heat resistance on the plastic part;

[0019] 3. The painted pattern obtained by this process has the characteristics of high drop, that is, a high-precision pattern with a drop of 0 - 15 mm can be achieved; the painted pattern has the characteristics of high color and high gloss, and the colors are more diverse;

[0020] 4. After painting, the pattern is directly cured by a UV curing lamp, which greatly improves the processing efficiency;

[0021] 5. The minimum size of the ink droplet can reach 5 pl, with high spraying accuracy, and high-definition printing can be achieved at 600 dpi; and the ignition frequency of the nozzle is as high as 50 KH, which can greatly improve the production efficiency;

[0022] 6. The pattern layer obtained by painting has high light transmission characteristics, and a display window pattern can be realized. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is the effect diagram of the painted pattern obtained by the painting process of the present invention.

[0024] Figure 2 It is the effect diagram of the pattern of the existing printing technology.

[0025] Figure 3 It is the window effect diagram of the painted pattern obtained by the painting process of the present invention DETAILED DESCRIPTION OF THE EMBODIMENTS

[0026] The present invention will be further described in detail below with reference to the drawings.

[0027] Example 1

[0028] The high-drop, high-color, and high-gloss injection panel painting process of the present invention includes the following steps:

[0029] S1. Select inks of corresponding colors and place them in respective corresponding ink cartridges in the painting machine;

[0030] S2. Place the plastic panel on the painting machine and perform inkjet painting on the plastic panel through the nozzles of the painting machine;

[0031] S3. Perform UV curing after the painting is completed;

[0032] The ink in step S1 is composed of the following components in respective parts by weight:

[0033] 15 parts of inorganic pigment, 10 parts of ethoxyethoxyethyl acrylate, 40 parts of 2-phenoxyethyl acrylate, 10 parts of N-vinylcaprolactam, and 5 parts of dipropylene glycol diacrylate.

[0034] Among them, ethoxyethoxyethyl acrylate is 2-(2-ethoxyethoxy)ethyl acrylate, and its CAS number is 7328-17-8;

[0035] 2-phenoxyethyl acrylate, and its CAS number is 48145-04-6;

[0036] N-vinylcaprolactam, and its CAS number is 2235-00-9;

[0037] Dipropylene glycol diacrylate, and its CAS number is 57472-68-1.

[0038] Among them, the inorganic pigment can be selected according to the colors of the patterns to be actually spray-painted to meet different requirements for the colors of the patterns; the inorganic pigment is selected so that the pigment itself does not contain volatile organic compounds, and at the same time, the other components in the ink do not contain VOC components of organic compounds. Therefore, after the ink is spray-painted, it will not emit harmful components such as VOC, greatly reducing environmental pollution and achieving an environmental protection effect.

[0039] The pattern obtained by painting with the above ink has the characteristics of waterproof, sunscreen, and scratch resistance after UV rapid curing, extending the service life of the product and being able to maintain stable colors and performance during long-term use.

[0040] The painting machine in step S1 uses a UV flatbed inkjet printer. There are multiple nozzles, and two ink cartridges are installed at each nozzle. A controller is provided on the painting machine, and each ink cartridge is electrically connected to the controller. During actual use, by controlling the ejection amount of the ink in each ink cartridge by the controller, it is possible to meet the requirements for painting patterns of different colors. Controlling the ejection amount of the ink in each ink cartridge by the controller is a prior art, and the specific control process will not be elaborated here.

[0041] Multiple nozzles are installed at each print head, and the number of nozzles on each print head is 1280. The size of the ink droplets ejected by the nozzles is 5 - 15 pL. In actual use, 4 print heads can be selected, and each print head is configured with 1280 nozzles, making the ink droplets small and delicate.

[0042] During painting, since the size of the ejected ink droplets can reach as small as 5 pL at the minimum, and the spraying accuracy is high, high-definition printing can be achieved at 600 dpi for a single color. When it is a two-color printing, the resolution can reach 300 dpi, making the patterns obtained by painting have a very high resolution. Moreover, the painted layer surface is smooth and has a high gloss after curing, with excellent abrasion resistance, weather resistance, and chemical resistance.

[0043] The print head can move in the X-axis direction, Y-axis direction, and Z-axis direction on the UV flatbed printer. The movement control method of the print head on the UV flatbed printer is an existing technology and will not be elaborated here. Through the movement of the print head in the X, Y, and Z-axis directions, spraying on different positions of the plastic panel can be achieved.

[0044] The ignition frequency of the print head can be as high as 50 KH, which greatly improves the inkjet efficiency of the print head and can significantly improve the production efficiency. There is a UV curing lamp on one side of the print head. Therefore, when the inkjet painting of the print head is completed, the painted area is directly cured by the UV curing lamp, and the cured ink has no peculiar smell; the curing efficiency is high and it can be completed in just a few seconds, greatly shortening the production cycle.

[0045] In actual use, this process can print different materials such as metal and ceramic in addition to the plastic panel, and the adhesion to materials such as metal and ceramic is also sufficient, with good alcohol resistance.

[0046] The painted pattern obtained by the high-drop, high-color, and high-gloss injection panel painting process of the present invention (as Figure 1 shown) can achieve the effect of high drop. The pattern drop can be in the range of 0 - 15 mm, with a good three-dimensional effect, and a pattern with high precision and high resolution can be obtained; through multiple print heads and multiple ink cartridges, the diversity of the colors of the painted pattern can be achieved, and the high-gloss full coverage of the pattern can be realized; the obtained pattern layer has the characteristic of high light transmittance, and a display window pattern can be realized (as Figure 3 shown). By comparing Figure 2 and Figure 3 , it can be seen that Figure 3 the pattern layer obtained by the process of this application has a better light transmittance effect; at the same time, the adhesion between the ink and the plastic panel is greatly enhanced, the hardness of the painted layer is ensured, the pollution to the environment during the printing process is reduced, and the environmental protection effect is achieved; and it has good weather resistance, heat and humidity resistance, water resistance, etc. Now, corresponding tests are carried out on the painted texture on the plastic panel, and the results are shown in the following table:

[0047]

[0048] Example 2

[0049] This example is basically the same as Example 1, and the achieved performance is also the same as that of Example 1. The difference is that the ink in step S1 is composed of the following components in parts by weight:

[0050] 10 parts of inorganic pigment, 5 parts of ethoxyethoxyethyl acrylate, 35 parts of 2-phenoxyethyl acrylate, 5 parts of N-vinylcaprolactam, and 1 part of dipropylene glycol diacrylate.

[0051] Example 3

[0052] This example is basically the same as Example 1, and the achieved performance is also the same as that of Example 1. The difference is that the ink in step S1 is composed of the following components in parts by weight:

[0053] 20 parts of inorganic pigment, 15 parts of ethoxyethoxyethyl acrylate, 45 parts of 2-phenoxyethyl acrylate, 15 parts of N-vinylcaprolactam, and 10 parts of dipropylene glycol diacrylate.

[0054] The above are only the preferred embodiments of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the inventive concept of the present invention, several modifications and improvements can still be made, and these all belong to the protection scope of the present invention.

Claims

1. High drop, high color and high gloss injection panel painting process, characterized by: The steps include: S1. Select ink of corresponding color and put it into the corresponding ink cartridges in the color plotter; S2, placing the plastic panel on a painting machine, and performing inkjet painting on the plastic panel through a nozzle of the painting machine; S3, UV curing after painting; The ink in step S1 is composed of the following components in parts by weight: 10 to 20 parts of inorganic pigments, 5 to 15 parts of ethoxyethoxyethyl acrylate, 35 to 45 parts of 2-phenoxyethyl acrylate, 5 to 15 parts of N-vinyl caprolactam and 1 to 10 parts of dipropylene glycol diacrylate.

2. The high drop, high color and high gloss injection panel painting process according to claim 1 is characterized in that: The color printer in step S1 is a UV flatbed inkjet printer with multiple nozzles, each of which is equipped with two ink cartridges. The color printer is provided with a controller, and each of the ink cartridges is electrically connected to the controller.

3. The high drop, high color and high gloss injection panel painting process according to claim 2 is characterized in that: A plurality of nozzles are installed at each of the nozzles, the number of nozzles on each nozzle is 1280, and the size of ink droplets ejected by the nozzles is 5-15 PL.

4. The high drop, high color and high gloss injection panel painting process according to claim 3 is characterized in that: The ignition frequency of the nozzle is ≤50KH.

5. The high drop, high color and high gloss injection panel painting process according to any one of claims 2 to 4, characterized in that: The nozzle can move in the X-axis direction, the Y-axis direction and the Z-axis direction on the UV flatbed inkjet printer.

6. The high drop, high color and high gloss injection panel painting process according to claim 5 is characterized in that: The texture resolution after printing by the nozzle is 600dpi in single color and 300dpi in double color.

7. The high drop, high color and high gloss injection panel painting process according to claim 2 is characterized in that: A UV curing lamp is arranged on one side of the nozzle.

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