In the market, we can see most of the wooden door products, the surface coating effect is completely closed transparent color effect, the use of paint varieties mainly PU paint. In this paper, we will use PU as a coating for the completely closed transparent color effect of the process introduction and the advantages and disadvantages of each process analysis.

The above basic process is suitable for the painting and coating operations of most wooden door enterprises. Only each factory in accordance with the product positioning of their respective enterprises, the materials used are different, on the basis of the above process made some adjustments, derived from many different process operations, the following we will focus on introducing a variety of derived process operations.

One: One bottom side

1. Process flow: white blank polishing → scraping → polishing → spraying transparent primer → polishing → spraying colored transparent surface.

2, product positioning: low-grade products.

3, the advantages: the process is the simplest, the painting cost is the lowest, in the case of the wood white blank has a relatively obvious defect, with wood color water ash to fill, colored transparent surface with a relatively deep color spraying, can better cover the defects of the substrate. The color is uniform.

4, disadvantages: the product has no permeability, can not see the natural texture of the wood beauty, the entire painting effect is similar to the solid color paint effect on the medium density board. Because only one primer is done, the filling property of the product is not good, the anti-sinking property is not good, and the surface paint film of the product is prone to wavy ups and downs, which greatly affects the overall beauty of the product. The grinding of water ash is the most time-consuming, the labor intensity is large, the dust is large, and the grinder is difficult to hire.

Bis: two bottom side (including water ash type)

1. Process flow: white blank polishing → scraping → polishing → spraying transparent primer → polishing → spraying transparent primer → polishing → spraying colored transparent surface.

2. Product positioning: medium and low grade.

3, advantages: the process is relatively simple, the coating cost is low, and it has better filling and sag resistance than the previous process.

4, disadvantages: the permeability of the product is not very good, the sense of layer is not strong, and the natural texture and beauty of the wood can not be well displayed. The grinding strength of water ash is large, and the dust is large.

5, suggestions: (1) change the wood color water ash to "colored water ash"; (2) Spray colored transparent paint instead of tinting with essential oil tinting, light grinding, and then spray transparent paint. This will greatly improve the permeability and layering of the product, so that the texture of the wood can be more clearly displayed, and the overall cost will not increase much.

Three: three bottom side

1. Process flow: white blank polishing → spraying transparent primer → polishing → spraying transparent primer → polishing → spraying transparent primer → polishing → tinting → light grinding → spraying clear finish paint.

2, product positioning: high-end products.

3, advantages: good permeability, can clearly show the natural texture of wood. The construction of water ash is eliminated and the strength of grinding is reduced.

4, disadvantages: high cost, the process has not been simplified, if it is a deep wood eye material, three times primer can not do a good fullness. If the wood grain of the material is finer, it can not enhance the effect of the wood grain texture (just the real performance).

5, Suggestions: (1) if the material wood eye is deep, the second primer can be wet and wet operation; (2) The second primer can also be changed from spraying to scraping, which not only greatly saves costs, but also gets a better painting effect.

Fourth: bottom coloring, surface repair color

1. Process flow: white blank polishing → spray sealing → grinding → PU Gris polishing → transparent primer spraying → Transparent primer spraying → Transparent primer polishing → Transparent primer spraying → color retouching → light grinding → clear finish spraying.

2, product positioning: high-grade products.

3, advantages: with very good permeability, layer (three-dimensional), even if the texture of the wood itself is not clear, through the above process operation, the texture can be more clearly shown.

4, disadvantages: high cost, long working time.

5, suggestions: (1) if the texture of the wood itself is very clear and beautiful, it is not necessary to use the bottom coloring (such as Shabili's veneer, directly do transparent primer, the wood eye itself will emit a flash red effect, very beautiful; But if the bottom coloring process will not show this effect); (2) After using the bottom coloring process, the color of the surface repair can be lighter, so that the layer sense and permeability are better.

Through the above process introduction and analysis, we can see that each process has its applicability, has its advantages and disadvantages. Therefore, when we choose the process, we must take into account the actual needs and conditions to choose the right process, otherwise it is difficult to achieve their ideal effect, sometimes spend more costs, can not do their own desired effect and quality.

Today, the prosperity of the wooden door manufacturing industry also means that the competition in the industry is increasingly fierce, and the overall trend of profit margins of wooden door manufacturing and sales is getting lower and lower. How to maximize the control of costs, improve quality, improve production efficiency, this is placed in front of every practitioner of the subject. Does improving quality mean increasing costs? On the surface: Yes. But it's not.

Some people say that I want the effect of the "bottom coloring, top coloring" process, but also want the process to be simpler and less costly. In fact, it can be done. Some factories have been mature in the use of new materials to replace the previous water ash, so that it not only has a good filling, construction, but also can achieve the effect of bottom coloring. The use of new materials can optimize the process, reduce costs and improve efficiency.

When the paint is just applied, people mostly use the brush coating method, and then use the spray method, which greatly improves the production efficiency and quality. However, people have ignored that there are many ways to paint, and some factories choose the scraping method, which not only greatly saves costs, improves efficiency, and makes the effect better.

Therefore, painting as a science, it is like all other scientific fields, with endless exploration. It is always evolving and evolving.

Engineers question answers

Q: We just made the door, the surface is very smooth, but after more than a month, found that the surface luster is not so bright, the surface is not so smooth, may I ask why?

Answer: Mainly the paint film sinking. The sinking of the paint film will cause the surface to be uneven, and the surface of the uneven will make the light reflection astigmatism, resulting in a decrease in luster.

Countermeasures: In order to do a good job of closing the bottom layer, the bottom coating operation must fill the wood eye, the dry time should be sufficient, and the grinding should be thorough, so that the occurrence of the above situation can be better controlled.

Q: The average cost of painting a set of doors (5.3 square meters) is more than 200 yuan, so we have changed several paint suppliers, the unit price of paint has dropped a little, but the overall cost is high, how can we reduce the cost?

A: The cost control of painting is a system engineering, just the selection of cheaper paint unit price is not to solve the fundamental problem.

We think we can start from the following three aspects: first, choose the most suitable process; Second, control the rework rate; The third is to improve the quality of operators.