Ink printing process for backlight module and backlight module

Abstract

The invention relates to the technical field of backlight module printing, in particular to an ink printing process for a backlight module, which comprises the following steps: step 1, cleaning and drying a carrier needing ink printing to obtain a pretreated carrier; step 2, uniformly printing water-based UV ink on a carrier to obtain an ink layer with a preset thickness; step 3, performing freeze-drying treatment on the ink layer on the carrier to obtain a freeze-dried ink layer; step 4, performing low-temperature grinding treatment on the freeze-dried ink layer; 5, light curing treatment is conducted after the ink layer recovers to the room temperature, in the printing process of the ink printing technology of the backlight module, freeze-drying treatment is conducted on the ink layer on the carrier, low-temperature presetting is conducted on the ink layer, the freeze-dried ink layer can keep a relatively complete shape, and during subsequent grinding treatment, the ink layer is not prone to falling off, so that the ink layer is not prone to falling off. And micropores can be filled and leveled up, and high flatness of the ink surface is ensured.

Description

Technical Field

[0001] The present invention relates to the technical field of backlight module printing technology, and in particular to an ink printing process for backlight modules and backlight modules. Background Art

[0002] In the manufacturing process of traditional backlight modules, whether it is a direct-lit backlight module or a side-lit backlight module, the ink printing process is often used. For example, black ink is printed on the iron frame to absorb light and reduce light leakage, white ink is printed on the lamp board to improve the reflectivity of the lamp board, or gradient ink is printed on the diffusion film to reduce the phenomenon of lamp eyes.

[0003] The problem is that after the ink is printed on the corresponding carrier such as film material, it needs to be baked to form an ink layer by volatilizing the solvent. The volatilizing solvent forms pores on the surface of the ink layer during volatilization, and the pores have a large diameter and a deep depth. The maximum pore diameter is close to 1 mm, and the ink around the pores shows obvious depressions or protrusions, resulting in the uneven surface of the ink layer, which affects the function of the ink layer to reflect light or absorb light. Therefore, how to improve the surface flatness of the ink layer and increase the function of the ink layer to reflect light or absorb light has become an urgent technical problem to be solved.

[0004] Therefore, we propose an ink printing process for backlight modules and backlight modules to solve the above problems. Summary of the Invention

[0005] The purpose of the present invention is to solve the disadvantages existing in the prior art, and to propose an ink printing process for backlight modules and backlight modules.

[0006] The ink printing process for backlight modules includes the following steps:

[0007] Step 1: Clean and dry the carrier to be ink-printed to obtain a pretreated carrier;

[0008] Step 2: Uniformly print aqueous UV ink onto the carrier to obtain an ink layer with a preset thickness;

[0009] Step 3: Freeze-dry the ink layer on the carrier to obtain a freeze-dried ink layer;

[0010] Step 4: Perform low-temperature leveling treatment on the freeze-dried ink layer;

[0011] Step 5: Perform photocuring treatment after the ink layer returns to room temperature.

[0012] Preferably, in the step 2, the thickness of the ink layer is 50-80 μm.

[0013] Preferably, in step 3, when freeze-drying is carried out, the treatment temperature is -25 to -18°C; in step 4, when low-temperature grinding is carried out, the treatment temperature is -25 to -18°C.

[0014] Preferably, in step 4, when low-temperature grinding is carried out, the mesh number of the grinding wheel is 400 to 500 meshes.

[0015] Preferably, in step 5, the irradiation power of ultraviolet light is 400 to 800 joules, the vertical distance between the ultraviolet lamp tube and the ink layer is controlled below 20 cm, and it is cured for 15 to 20 minutes at a temperature of 25 to 40°C, and then cured for 10 to 15 minutes at a temperature of 40 to 70°C.

[0016] Preferably, the water-based UV ink comprises the following components in parts by weight: 60 to 70 parts of water-based polyurethane resin, 6 to 9 parts of pigment, 25 to 30 parts of dispersant, 2 to 4 parts of photoinitiator, 1 to 3 parts of leveling agent, 1.5 to 2.5 parts of other additives, and 55 to 65 parts of deionized water.

[0017] Preferably, the leveling agent adopts an organosilicon leveling agent.

[0018] Preferably, the other additives are a mixture of dibutyl phosphate, sodium alkyl sulfonate and phosphate ester double starch, and the mass ratio of dibutyl phosphate, sodium alkyl sulfonate and phosphate ester double starch is (2 to 5):(4 to 7):1.

[0019] Preferably, a backlight module comprises a carrier and an ink layer, and the ink layer on the carrier is printed by using the above-mentioned ink printing process for the backlight module.

[0020] The beneficial effects of the present invention are as follows:

[0021] 1. For the ink printing process of the backlight module proposed by the present invention, during the printing process, the ink layer on the carrier is freeze-dried to perform low-temperature pre-shaping on the ink layer. The freeze-dried ink layer can maintain a relatively complete shape. As the water content decreases, some micropores will appear on the ink layer. The diameter of the micropores is generally less than 20 μm, and the diameter of the micropores is much smaller than that of the bubble holes, and the ink near the micropores will not sink or bulge. During the subsequent grinding process, the micropores can be filled, ensuring a high flatness of the ink surface.

[0022] 2. For the ink printing process of the backlight module proposed by the present invention, the water-based UV ink contains a mixture of dibutyl phosphate, sodium alkyl sulfonate and phosphate ester double starch, which can effectively ensure the stability of the water-based UV ink at low temperatures and ensure that the water-based UV ink can be used normally after freeze-drying. Detailed implementation manners

[0023] The present invention will be further explained below in conjunction with specific embodiments.

[0024] In Example 1, the ink printing process for the backlight module includes the following steps:

[0025] Step 1: Clean and dry the carrier to be ink-printed to obtain a pre-treated carrier;

[0026] Step 2: Uniformly print the water-based UV ink onto the carrier to obtain an ink layer with a preset thickness;

[0027] Step 3: Freeze-dry the ink layer on the carrier to obtain a freeze-dried ink layer;

[0028] Step 4: Perform low-temperature leveling treatment on the freeze-dried ink layer;

[0029] Step 5: Perform photocuring treatment after the ink layer returns to room temperature.

[0030] In Step 2, the thickness of the ink layer is 50 μm.

[0031] In Step 3, when performing the freeze-drying treatment, the treatment temperature is -25°C; in Step 4, when performing the low-temperature leveling treatment, the treatment temperature is -25°C.

[0032] In Step 4, when performing the low-temperature leveling treatment, the mesh number of the grinding wheel is 400 mesh.

[0033] In Step 5, the irradiation power of the ultraviolet light is 400 joules, the vertical distance between the ultraviolet lamp tube and the ink layer is controlled below 20 cm, and it is cured for 15 min at a temperature of 25°C, and then cured for 10 min at a temperature of 40°C.

[0034] The water-based UV ink includes the following components by weight: 60 parts of water-based polyurethane resin, 6 parts of pigment, 25 parts of dispersant, 2 parts of photoinitiator, 1 part of leveling agent, 1.5 parts of other additives, and 55 parts of deionized water.

[0035] The leveling agent uses an organosilicon leveling agent.

[0036] The other additives are a mixture of dibutyl phosphate, sodium alkyl sulfonate, and phosphate ester double starch, and the mass ratio of dibutyl phosphate, sodium alkyl sulfonate, and phosphate ester double starch is 2:4:1.

[0037] In Example 2, the ink printing process for the backlight module includes the following steps:

[0038] Step 1: Clean and dry the carrier to be ink-printed to obtain a pre-treated carrier;

[0039] Step 2: Uniformly print the water-based UV ink onto the carrier to obtain an ink layer with a preset thickness;

[0040] Step 3: Subject the ink layer on the carrier to freeze-drying treatment to obtain a freeze-dried ink layer;

[0041] Step 4: Conduct low-temperature leveling treatment on the freeze-dried ink layer;

[0042] Step 5: Perform photocuring treatment after the ink layer returns to room temperature.

[0043] In Step 2, the thickness of the ink layer is 80 μm.

[0044] In Step 3, when performing the freeze-drying treatment, the treatment temperature is -18°C; in Step 4, when performing the low-temperature leveling treatment, the treatment temperature is -18°C.

[0045] In Step 4, when performing the low-temperature leveling treatment, the mesh number of the grinding wheel is 500 mesh.

[0046] In Step 5, the irradiation power of the ultraviolet light is 800 joules, the vertical distance between the ultraviolet lamp tube and the ink layer is controlled below 20 cm, and it is cured for 20 min at a temperature of 40°C, and then cured for 15 min at a temperature of 70°C.

[0047] The water-based UV ink includes the following components by weight: 70 parts of water-based polyurethane resin, 9 parts of pigment, 30 parts of dispersant, 4 parts of photoinitiator, 3 parts of leveling agent, 2.5 parts of other additives, and 65 parts of deionized water.

[0048] The leveling agent uses a silicone-based leveling agent.

[0049] The other additives are a mixture of dibutyl phosphate, sodium alkyl sulfonate, and phosphate ester double starch, and the mass ratio of dibutyl phosphate, sodium alkyl sulfonate, and phosphate ester double starch is 5:7:1.

[0050] In Example 3, the ink printing process for the backlight module includes the following steps:

[0051] Step 1: Clean and dry the carrier to be ink-printed to obtain a pretreated carrier;

[0052] Step 2: Uniformly print the water-based UV ink onto the carrier to obtain an ink layer with a preset thickness;

[0053] Step 3: Subject the ink layer on the carrier to freeze-drying treatment to obtain a freeze-dried ink layer;

[0054] Step 4: Conduct low-temperature leveling treatment on the freeze-dried ink layer;

[0055] Step 5: Perform photocuring treatment after the ink layer returns to room temperature.

[0056] In Step 2, the thickness of the ink layer is 60 μm.

[0057] In Step 3, when performing freeze-drying treatment, the treatment temperature is -20°C; in Step 4, when performing low-temperature leveling treatment, the treatment temperature is -20°C.

[0058] In Step 4, when performing low-temperature leveling treatment, the mesh number of the grinding wheel is 450 mesh.

[0059] In Step 5, the irradiation power of the ultraviolet light is 600 joules, the vertical distance between the ultraviolet lamp tube and the ink layer is controlled to be below 20 cm, and it is cured for 18 min at a temperature of 30°C, and then cured for 12 min at a temperature of 50°C.

[0060] The water-based UV ink includes the following components by weight: 65 parts of water-based polyurethane resin, 7 parts of pigment, 26 parts of dispersant, 3 parts of photoinitiator, 2 parts of leveling agent, 2 parts of other additives, and 60 parts of deionized water.

[0061] The leveling agent uses an organosilicon leveling agent.

[0062] The other additives are a mixture of dibutyl phosphate, sodium alkyl sulfonate, and phosphate ester double starch, and the mass ratio of dibutyl phosphate, sodium alkyl sulfonate, and phosphate ester double starch is 3:5:1.

[0063] A backlight module includes a carrier and an ink layer, and the ink layer on the carrier is printed by using the above-mentioned ink printing process for the backlight module.

[0064] In Examples 1-3, in the ink printing process of the backlight module proposed by the present invention, during the printing process, the ink layer on the carrier is subjected to freeze-drying treatment, and the ink layer is pre-shaped at low temperature. After freeze-drying, the ink layer can maintain a relatively complete shape. As the water content decreases, some micropores will appear on the ink layer. The diameter of the micropores is generally less than 20 μm. The diameter of the micropores is much smaller than that of the bubble holes, and the ink near the micropores will not sink or bulge. During the subsequent leveling treatment, the micropores can be filled to ensure a high flatness of the ink surface.

[0065] In the ink printing process of the backlight module proposed by the present invention, the water-based UV ink contains a mixture of dibutyl phosphate, sodium alkyl sulfonate, and phosphate ester double starch, which can effectively ensure the stability of the water-based UV ink at low temperature and ensure that the water-based UV ink can be used normally after freeze-drying.

[0066] The above are only the preferred specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention, according to the technical solution and inventive concept of the present invention, making equivalent substitutions or changes, shall be covered by the protection scope of the present invention.

Claims

1. An ink printing process for a backlight module, characterized in that: The following steps are involved: Step 1: Clean and dry the carrier to be printed with ink to obtain a pretreated carrier; Step 2, printing water-based UV ink evenly on the carrier to obtain an ink layer with a preset thickness; Step 3, freeze-drying the ink layer on the carrier to obtain a freeze-dried ink layer; Step 4, performing low temperature grinding treatment on the freeze-dried ink layer; Step 5: After the ink layer returns to room temperature, perform light curing.

2. The ink printing process for backlight module according to claim 1, characterized in that: In the step 2, the thickness of the ink layer is 50 to 80 μm.

3. The ink printing process for backlight module according to claim 1, characterized in that: In the step 3, when freeze-drying is performed, the processing temperature is -25 to -18°C; in the step 4, when low-temperature polishing is performed, the processing temperature is -25 to -18°C.

4. The ink printing process for backlight module according to claim 1, characterized in that: In step 4, when the low temperature grinding treatment is performed, the mesh number of the grinding wheel is 400 to 500 meshes.

5. The ink printing process for backlight module according to claim 1, characterized in that: In the step 5, the irradiation power of the ultraviolet light is 400-800 joules, the vertical distance between the ultraviolet lamp and the ink layer is controlled below 20 cm, and the curing is performed at a temperature of 25-40° C. for 15-20 minutes, and then at a temperature of 40-70° C. for 10-15 minutes.

6. The ink printing process for backlight module according to claim 1, characterized in that: The water-based UV ink comprises the following components by weight: 60-70 parts of water-based polyurethane resin, 6-9 parts of pigment, 25-30 parts of dispersant, 2-4 parts of photoinitiator, 1-3 parts of leveling agent, 1.5-2.5 parts of other additives and 55-65 parts of deionized water.

7. The ink printing process for backlight module according to claim 1, characterized in that: The leveling agent is an organosilicon leveling agent.

8. The ink printing process for backlight module according to claim 1, characterized in that: The other auxiliary agent is a mixture of dibutyl phosphate, sodium alkyl sulfonate and distarch phosphate, wherein the mass ratio of dibutyl phosphate, sodium alkyl sulfonate and distarch phosphate is (2-5): (4-7):

1.

9. A backlight module, comprising a carrier and an ink layer, characterized in that: The ink layer on the carrier is printed by using the ink printing process for a backlight module as described in any one of claims 1 to 8.