WO2019037262A1 - Coating material and preparation method and spraying method thereof - Google Patents

Abstract

A coating material, comprising: 70-87% of waterborne polyurethane; 5-20% of a color paste; 0.5-6% of a film-forming assistant; 0.05-0.5% of a defoaming agent; 0.1-0.8% of a wetting agent; 0.05-1% of a thickening agent; and the balance being water. A preparation method of the coating material is: sequentially adding the color paste, the film-forming assistant, water, the defoaming agent, the wetting agent, and the thickening agent into the waterborne polyurethane according to requirements on the proportions, and mixing evenly to obtain the coating material. A spraying method of the coating material is: (1) preparing the coating material according to the requirements on the proportions; (2) adding a proper amount of the compounded coating material into a spray gun; (3) preheating a slush-molded skin in a heating furnace under a temperature of 50-80°C for 3-15 min, removing the heated skin, putting same with the back side up on a stationary fixture, making an airbag area fixed and flat, evenly spraying, by means of the spay gun, the prepared coating material on the back surface of a complete skin airbag area, and waiting till the coating material is completely dried.

Description

Coating material, configuration method thereof and spraying method Technical field

The invention relates to a coating material, in particular to a PVC plastic skin, in particular to a coating material, a method for its arrangement and a spraying method.

Background technique

The plastic skin is a skin material obtained by slush-molding processing. Currently, the PVC plastic skin is mainly used on the market. Because PVC plastic skin has the advantages of not easy to crack, stable size, uniform thickness, clear texture, good hand feeling, etc., it also has considerable advantages in terms of aging resistance, heat resistance, anti-bleeding and scratch resistance, so it has become a Ideal for automotive interior materials, such as the skin of automotive dashboards.

However, due to the high glass transition temperature of the PVC plastic skin, it is easy to be brittle at low temperatures, and the thickness of the PVC plastic skin used in the automotive interior is usually 1.0 to 1.4 mm, so it is easy to be at low temperature. Fragmentation splash. Especially when the airbag is blasted at a low temperature, the PVC plastic skin of the airbag area of the instrument panel often has the problem of cracking and splashing of the skin, which brings a huge safety hazard.

Although it has been reported in the literature that polyurethane coatings can be sprayed on PVC plastic skin to improve the low temperature characteristics of PVC plastic skin, there is still a problem of chipping and splashing at low temperatures. At the same time, due to the low viscosity of the polyurethane coating, it is easy to flow when spraying the polyurethane coating on the vertically suspended PVC plastic skin; while the thickness of the film is not uniform when spraying on the horizontally placed PVC plastic skin, resulting in construction difficulties.

Summary of the invention

In order to overcome the deficiencies in the prior art, the present invention provides a coating material, a method for arranging the same, and a spraying method for effectively improving the low temperature blasting performance of the PVC plastic skin and at the same time solving the problem of construction difficulty.

The present invention first provides a coating material comprising the following mass percentage components:

The coating material provided by the invention is based on water-based polyurethane as a base material, and is compounded with a color paste, a film-forming auxiliary agent, a defoaming agent, a wetting agent, a thickener and water according to a certain ratio, and can effectively improve PVC搪The low-temperature blasting performance of the plastic skin, and solves the problem that the conventional polyurethane coating is difficult to construct and the spraying effect is not ideal.

As a preferred aspect of the present invention, the above coating material can be formulated in the following percentage by mass:

Specifically, as the basic component and main component of the coating material, the performance of the waterborne polyurethane significantly affects the overall performance of the coating material, so the selection of the flexible polyurethane with good low temperature performance is the overall performance of the coating material. Advantageously, aliphatic aqueous polyurethanes are generally selected. In the practice of the present invention, the viscosity of the aqueous polyurethane used is usually not more than 1200 mPa·s, for example, 100 mPa·s to 1200 mPa·s, and an aqueous polyurethane having a solid content of 35% to 55% is generally selected. In order to ensure the water resistance of the aqueous polyurethane, the pH of the commonly selected aqueous polyurethane is 6 to 10. Specifically, a commercially available aqueous polyurethane dispersion product such as WBD-390 aqueous polyurethane dispersion or WBD-408 aqueous polyurethane dispersion of Shanghai Wech Company can be selected. The WBD-390 aqueous polyurethane dispersion has a solid content of 50±2%, a pH of 8.0-9.5, a viscosity of 100-800 mPa·s (23 ° C), and a WBD-408 aqueous polyurethane dispersion having a solid content of 40±2. %, pH 7.5 ± 1.5, viscosity <1200 mPa·s (23 ° C).

A film forming aid can be used to improve the viscosity and film forming properties of the coating material. In the specific implementation of the present invention, a strong solvent of an ether alcohol polymer is generally used, such as dipropylene glycol methyl ether or twelve carbon. Alcohol ester.

Defoamer can be used to improve the surface tension of the coating material, avoiding the generation of bubbles during the process of disposing the coating material, but the amount of defoaming agent added is too large, and it is easy to reduce the mechanical properties of the coating obtained after the coating material is solidified. It is not conducive to improving the low temperature blasting performance of PVC plastic skin. In the practice of the present invention, the mass percentage of the antifoaming agent in the coating material is usually from 0.1% to 0.5%. The selection of the antifoaming agent in the present invention is not particularly limited, and an aqueous defoaming agent which is commonly used on the market and is safe and non-toxic, such as Corning's molecular grade defoamer product Fast301, can be generally selected.

The wetting agent can also improve the surface tension of the coating material, making the coating material easy to coat on the PVC plastic skin to facilitate leveling. However, if the content of the wetting agent is too high, it will also affect the mechanical properties of the coating material after curing, which is not conducive to improving the low temperature blasting performance of the PVC plastic skin. Generally, the content of the wetting agent is controlled to 0.2% to 0.7%. In the practice of the present invention, the wetting agent selected may be a commonly used wetting agent in aqueous coatings, such as acetylenic diol ethoxylates.

The invention does not particularly limit the selection of the color paste, and can be reasonably selected according to the application environment of the actual coating material. A safe, non-toxic aqueous colorant is usually used to provide good compatibility with other components such as waterborne polyurethane.

The thickener can increase the viscosity of the coating material, make the coating material smooth during the construction process, and improve the leveling of the coating, thereby facilitating a smooth, smooth and uniform coating. However, as the amount of thickener added increases, the film forming property of the coating material decreases, resulting in uneven film thickness, which leads to the failure of the PVC plastic skin to be used normally, and the content of the thickener is usually controlled to be 0.1% to 1%. For example, 0.1% to 0.7%, the mass ratio of the thickener to the wetting agent can be further controlled to be (1:3.5) to (1.5:1), and the mass ratio of the thickener to the antifoaming agent is (1 to 2.5). :1. In the specific implementation of the present invention, an aqueous polyurethane thickener may be selected.

In order to further adjust the viscosity of the coating material, prevent sedimentation delamination during the long-term placement of the coated coating material, and facilitate subsequent spraying of the coating material, the coating material of the present invention may further comprise a matting powder. The mass percentage thereof in the coating material may specifically be from 0.01% to 1%, usually from 0.5% to 1%. If the particle size of the matting powder is too small or too large, the deposited coating material may settle and stratify during long-term placement. Generally, the average particle size of the matting powder used is about 3 μm to 10 μm.

The above matting powder may be a matting powder commonly used in waterborne coatings, such as silica. In the specific implementation process of the present invention, Germany Degussa Corporation (now renamed Evonik Industries Group) was selected. The matting powder TS100 has an average particle diameter of 9.5 μm and a silica mass content of 99.8%.

The above coating material provided by the invention is based on water-based polyurethane as a base material and a main component, and is compounded with other components in a certain ratio to have a very suitable viscosity, and generally can reach 1000-4600 mPa·s (20). ～30°C); at the same time, the coating material also has very good film forming properties. Therefore, when spraying on the PVC plastic skin, no problem of runny occurs, and after the curing is completed, the flatness can be obtained. Higher, better mechanical properties of the coating, which can improve the low temperature blasting performance of PVC plastic skin.

The present invention provides a method for arranging the above coating material, which comprises: sequentially adding a color paste, a film forming aid, water, an antifoaming agent, a wetting agent and a thickener to the aqueous polyurethane, and uniformly mixing to obtain a coating material. .

The coating material obtained by the above method can make the coating material have good uniformity and stability, can not only prevent sedimentation of the inorganic particles therein, but also can avoid generating a large amount of bubbles. When placed at a temperature of about 25 ° C for about 3 months, there is no phenomenon such as sedimentation delamination.

If the coating material contains a matting powder, the method comprises the steps of: sequentially adding a color paste, a matting powder, a film forming aid, water, an antifoaming agent, a wetting agent and a thickening agent to the aqueous polyurethane, and uniformly mixing, thereby obtaining Coating material.

The invention also provides a method for spraying a PVC plastic skin, using the above coating material, comprising the following steps:

Preheating the PVC plastic skin;

The above coating material is sprayed onto the surface of the preheated PVC plastic skin, and then the coating material is cured completely.

Specifically, an appropriate amount of coating material may be firstly added to the spray gun for use, and the PVC plastic skin is preheated, and then the PVC plastic skin after the preheating is removed, and the back surface (that is, the commonly called B surface) is outwardd. And flattened on the fixture, and then sprayed the coating material evenly on the back of the PVC plastic skin with a spray gun. After the coating material is completely cured, the coating on the surface of the PVC plastic skin is obtained, that is, the coating material is completed. Spraying process.

Since the coating material provided by the invention has a suitable viscosity and has good adhesion to the surface of the PVC plastic skin, it can be sprayed into a film on a horizontally placed or even vertically suspended plastic skin, and can also be The coating has very good flatness and mechanical properties.

Appropriate preheating of the PVC plastic skin can make the coating material and PVC plastic skin Good adhesion between the two. If the preheating temperature is too high or too low, the adhesion between the two will be lowered, and the final film forming property of the coating material will be affected, but the low temperature blasting performance of the PVC plastic skin can not be effectively improved. For example, when the preheating temperature exceeds 100 ° C, the coating material cannot be uniformly formed on the PVC plastic skin, and the adhesion between the two will be greatly reduced. At the same time, the preheating temperature is too high, and the temperature between the inner layer and the surface of the PVC plastic skin is inconsistent, and cracks may occur in severe cases. Generally, the preheating temperature is not higher than 80 ° C, and the preheating time is not less than 3 min. For example, the PVC plastic skin is preheated at a temperature of 50 to 80 ° C for 3 to 15 minutes. In the specific implementation process of the present invention, the preheating temperature can be controlled to be 60 to 80 ° C, and the preheating time is 5 to 15 minutes.

The curing of the above coating material can be carried out specifically at a temperature of from 15 ° C to 80 ° C. In the specific implementation of the present invention, the curing is generally completed at room temperature; of course, in order to accelerate the curing speed, the curing temperature may be appropriately increased. The product obtained after the curing is completed can be directly stored without further cooling, which can reduce the design constraints of the spray process and increase the design space.

The present invention also provides a skin material comprising at least a PVC plastic skin and a coating disposed on a surface of the PVC plastic skin, wherein the coating is formed by spraying as described above.

Specifically, the above coating is disposed on the back of the PVC plastic skin, such as a PVC plastic skin for the skin of the instrument panel, and the above coating should be disposed at least in the airbag area of the B side of the PVC plastic skin. In this way, when the airbag is blasted at a low temperature, the skin of the instrument panel airbag region can be prevented from being shattered and splashed.

The thickness of the above coating can be reasonably set according to the practical application scene of the PVC plastic skin. For example, the coating used for the skin of the dashboard of a car, the thickness of which is usually about 0.30±0.05mm, and the difference in thickness is not more than 0.05, which can not only improve the blasting performance of the PVC plastic skin at low temperature, but also does not affect the interior of the car. Lightweight and thin walled.

The invention finally provides an automobile instrument panel having an instrument panel skin, the skin of which is made of the above-mentioned skin material, wherein the coating is disposed on the back of the PVC plastic skin.

Specifically, the automobile instrument panel comprises an instrument panel skeleton, a foam layer located on the outer layer of the dashboard skeleton, and an instrument panel skin disposed on the surface of the foam layer, the coating being disposed on the back surface (B side) of the PVC plastic skin, at least It should be placed in the airbag area of the instrument panel.

Unless otherwise specified, the PVC in the present invention refers to polyvinyl chloride.

The invention provides a coating material, which is based on water-based polyurethane and is compounded with other components, so that the coating material has very suitable viscosity and film-forming property, which is not only beneficial for subsequent spraying Construction, and the coating material can be sprayed into a film on a vertically suspended or horizontally disposed PVC plastic skin, which solves the problem that the pure polyurethane coating is vertically suspended and sprayed, resulting in construction difficulties.

The coating material provided by the invention can effectively improve the low temperature blasting performance of the PVC plastic skin, solve the problem of the fragmentation and splashing of the traditional PVC plastic skin at low temperature, and further expand the application space of the PVC plastic skin.

The method for arranging the coating material provided by the invention has a simple process and can make the disposed coating material have good uniformity and stability, and is favorable for industrialization.

The method for spraying the PVC plastic skin provided by the invention has a wide spraying temperature range and can be cured to form a film at room temperature or higher temperature, so the method is simple and easy. And after the film is cured, the PVC plastic skin can be directly stored without additional cooling, which reduces the design constraints of the spray process and increases the design space.

The skin material provided by the invention adopts the above method to spray and solidify the coating material on the surface of the PVC plastic skin, and the thickness thereof is uniform, and the low temperature blasting performance of the PVC plastic skin can be improved to avoid the problem of chipping and splashing. It can be used as a car interior, such as the dashboard of a car, without affecting the weight and thinness of the car interior.

The automobile instrument panel provided by the invention has an instrument panel skin comprising a PVC plastic skin and the above coating disposed on the PVC plastic skin. When the airbag is blasted at a low temperature, since the above coating is provided, the airbag region does not suffer from chipping and splashing, and the safety and reliability of the instrument panel and the automobile are further improved.

DRAWINGS

Figure 1 is a photograph of the coating material in Example 1 after spraying is completed;

2 is a photo of a low temperature airbag blasting experiment in Embodiment 1;

3 is a photo of a high temperature airbag blasting experiment in the first embodiment;

4 is a photo of a low temperature airbag blasting experiment in Embodiment 2;

Figure 5 is a photo of a high temperature airbag blasting experiment in the second embodiment;

6 is a photo of a low temperature airbag blasting experiment in Embodiment 3;

7 is a photo of a high temperature airbag blasting experiment in Embodiment 3;

Figure 8 is a photograph of the coating material in Comparative Example 1 after spraying is completed;

Fig. 9 is a photograph of a low temperature airbag blasting experiment in Comparative Example 1.

Detailed ways

The invention is further described below, but is not to be construed as limiting the scope of the invention.

Example 1

This embodiment provides a coating material having a total mass content of 100%, including the following components:

Waterborne polyurethane (WBD-390, Shanghai Weiqi Chemical Co., Ltd.) 85wt%, color paste 5wt%, filming aid (dipropylene glycol methyl ether) 4wt%, defoamer (Fast301, Corning) 0.2wt%, run The wet agent (acetylene glycol ethoxylate) was 0.4% by weight, the thickener (aqueous polyurethane thickener) was 0.4% by weight, and the balance was water.

The coating material is configured as follows:

Step 1. Add a color paste to the aqueous polyurethane and stir evenly;

Step 2, sequentially adding a film forming aid and water to the system of step 1, and stirring uniformly;

Step 3, adding antifoaming agent to the system of step 2, and stirring uniformly;

Step 4, adding a wetting agent to the system of step 3, stirring uniformly;

Step 5. Add a thickener to the system of step 4 and stir evenly to obtain a coating material.

The zero-cut viscosity of the coating material in this example was tested to be 1241.8 mPa·s (20 to 30 ° C).

Spraying the above coating material on the PVC plastic skin includes the following steps:

Take appropriate amount of the above coating material and add it to the spray gun for use;

The PVC plastic skin (thickness 0.6mm~1.2mm) used for the skin of the instrument panel is preheated in a heating furnace, the preheating temperature is about 75 ° C, and the preheating time is about 5 min;

Take out the PVC plastic skin after the preheating is completed, fix it on the fixture, make the PVC plastic skin vertical suspension and the back side facing outward, then spray the coating material on the surface of the airbag area with a spray gun, and then make it at room temperature (about Curing to a coating at 25 ° C) gave a skin material comprising a PVC plastic skin and a coating disposed on the back of the PVC plastic skin.

1 is a photograph of the coating material of the present embodiment before curing after spraying. As can be seen from FIG. 1, the coating material of the present embodiment is sprayed on a vertically disposed PVC plastic skin, and the coating material is sprayed smoothly. There are phenomena such as hooliganism.

The thickness of the above coating (unit: mm) was tested, and five representative test points were uniformly selected for testing and the range was calculated (the same applies to the following examples). The results are shown in Table 1.

Table 1

Sample number Test point 1 Test point 2 Test point 3 Test point 4 Test point 5 Very poor Example 1 0.27 0.28 0.31 0.31 0.26 0.05 Example 2 0.27 0.30 0.29 0.29 0.30 0.03 Example 3 0.30 0.28 0.27 0.31 0.26 0.05 Example 4 0.28 0.30 0.28 0.29 0.32 0.04 Example 5 0.29 0.27 0.30 0.30 0.31 0.04 Example 6 0.27 0.28 0.30 0.29 0.31 0.03 Example 7 0.28 0.29 0.27 0.31 0.30 0.04

As can be seen from Table 1, the coating obtained in this example has a thickness ranging from 0.26 mm to 0.31 mm, a range of 0.05, and a thickness uniformity conforming to a tolerance of ±0.05 for the film thickness of the spray coating process.

The above-mentioned skin material is subjected to a cold knife weakening operation. After the operation is completed, the skin material and the instrument panel skeleton are foamed, and the foamed instrument panel assembly is subjected to a -30 ° C low temperature and 85 ° C high temperature air bag blasting test.

Figures 2 and 3 are experimental photographs of low temperature and high temperature airbag blasting, respectively. It can be seen from FIG. 2 and FIG. 3 that the skin material obtained in the present embodiment is qualified in the blasting test at high temperature and low temperature, and particularly, no cracking or splashing occurs under low temperature blasting.

Example 2

This embodiment provides a coating material having a total mass content of 100%, including the following components:

Waterborne polyurethane (WBD-390, Shanghai Weiqi Chemical Co., Ltd.) 78wt%, color paste 14wt%, matting powder (matting powder TS100, Germany Degussa) 0.5wt%, filming aid (dipropylene glycol methyl ether) 3.8 Wt%, defoamer (Fast301, Corning) 0.18wt%, wetting agent (acetylene glycol ethoxylate) 0.37wt%, thickener (aqueous polyurethane thickener) 0.37wt%, the rest is water.

The coating material is configured as follows:

Step 1. Add a color paste to the aqueous polyurethane and stir evenly;

Step 2, adding matting powder to the system of step 1, and stirring uniformly;

Step 3, adding a film-forming auxiliary agent and water to the system of step 2, and stirring uniformly;

Step 4, adding antifoaming agent to the system of step 3, stirring uniformly;

Step 5, adding a wetting agent to the system of step 4, stirring uniformly;

Step 6. Add a thickener to the system of step 5 and stir evenly to obtain a coating material.

The coating material in this example was tested to have a viscosity of 1183 mPa·s (20 to 30 ° C).

Spraying the above coating material on the PVC plastic skin includes the following steps:

Take appropriate amount of the above coating material and add it to the spray gun for use;

The PVC plastic skin (thickness 0.6mm~1.2mm) used for the skin of the instrument panel is preheated in a heating furnace, the preheating temperature is about 65 ° C, and the preheating time is about 5 min;

Remove the PVC plastic skin after the preheating is completed, fix it on the fixture, make the back side of the PVC plastic skin face up, then spray the coating material on the surface of the airbag area with a spray gun, and then make it at about 45 °C. Curing into a coating results in a skin material comprising a PVC plastic skin and a coating disposed on the back of the PVC plastic skin.

During the above spraying process, the coating material was sprayed smoothly, and no bubbles or runny were observed.

The thickness of the above coating was tested. The test results are shown in Table 1. It can be seen from Table 1 that the coating obtained in this example has a thickness ranging from 0.27 mm to 0.30 mm and a calculated pole difference of 0.03. Therefore, the uniformity of the coating thickness conforms to the tolerance of the film thickness of the coating process of ±0.05.

The above-mentioned skin material is subjected to a cold knife weakening operation. After the operation is completed, the skin material and the instrument panel skeleton are foamed, and the foamed instrument panel assembly is subjected to a -30 ° C low temperature and 85 ° C high temperature air bag blasting test.

Figures 4 and 5 are experimental photographs of low temperature and high temperature airbag blasting, respectively. It can be seen from FIG. 4 and FIG. 5 that the skin material obtained in the present embodiment is qualified in the blasting test at high temperature and low temperature, and particularly, no cracking or splashing occurs under low temperature blasting.

Example 3

This embodiment provides a coating material having a total mass content of 100%, including the following components:

Waterborne polyurethane (WBD-390, Shanghai Weiqi Chemical Co., Ltd.) 86.5wt%, color paste 5wt%, filming aid (dipropylene glycol methyl ether) 4wt%, defoamer (Fast301, Corning) 0.35wt%, The wetting agent (acetylene glycol ethoxylate) was 0.4% by weight, the thickener (aqueous polyurethane thickener) was 0.4% by weight, and the balance was water.

The method of arranging the coating material is the same as in Embodiment 1. The zero-cut viscosity of the coating material in this example was tested to be 2240 mPa·s (20 to 30 ° C).

In the same manner as in Example 1, the above coating material was sprayed on a PVC plastic skin to obtain a skin material after curing. The coating material was sprayed smoothly during the spraying process, and no phenomenon such as runny was observed.

The thickness of the coating in the above skin material was measured, and the results are shown in Table 1. As can be seen from Table 1, the coating obtained in this example has a thickness ranging from 0.26 mm to 0.31 mm and a range of 0.05, thus coating The thickness is uniform and meets the tolerance of ±0.05 of the film thickness of the spraying process.

The above-mentioned skin material is subjected to a cold knife weakening operation. After the operation is completed, the skin material and the instrument panel skeleton are foamed, and the foamed instrument panel assembly is subjected to a -30 ° C low temperature and 85 ° C high temperature air bag blasting test.

Figures 6 and 7 are experimental photographs of low temperature and high temperature airbag blasting, respectively. It can be seen from Fig. 6 and Fig. 7 that the skin materials obtained in the present embodiment are all qualified in the blasting test at high temperature and low temperature, especially in the case of low temperature blasting.

Example 4

This embodiment provides a coating material having a total mass content of 100%, including the following components:

Waterborne polyurethane (WBD-408, Shanghai Weiqi Chemical Co., Ltd.) 72wt%, color paste 18wt%, filming aid (dodecanol ester) 2.5wt%, defoamer (Fast301, Corning) 0.1wt% The wetting agent (acetylene glycol ethoxylate) was 0.25 wt%, the thickener (aqueous polyurethane thickener) was 0.3 wt%, and the balance was water.

The method of arranging the coating material is the same as in Embodiment 1. The zero-cut viscosity of the coating material in this example was tested to be 4110.3 mPa·s (20 to 30 ° C).

In the same manner as in Example 1, the above coating material was sprayed on a PVC plastic skin to obtain a skin material after curing. The coating material was sprayed smoothly during the spraying process, and no phenomenon such as runny was observed.

The thickness of the coating in the above skin material was measured, and the results are shown in Table 1. As can be seen from Table 1, the coating obtained in this example has a thickness ranging from 0.28 mm to 0.32 mm and a calculated pole difference of 0.04. Therefore, the thickness of the coating layer is uniform, which meets the tolerance of the coating film thickness of ±0.05.

The above-mentioned skin material is subjected to a cold knife weakening operation. After the operation is completed, the skin material and the instrument panel skeleton are foamed, and the foamed instrument panel assembly is subjected to a -30 ° C low temperature and 85 ° C high temperature air bag blasting test. Both the low temperature test and the high temperature test were qualified, especially in the low temperature explosion without cracking and splashing.

Example 5

This embodiment provides a coating material having a total mass content of 100%, including the following components:

Waterborne polyurethane (WBD-408, Shanghai Weiqi Chemical Co., Ltd.) 80wt%, color paste 8wt%, filming aid (dodecanol ester) 3.5wt%, defoamer (Fast301, Corning) 0.25wt% The wetting agent (acetylene glycol ethoxylate) was 0.5% by weight, the thickener (aqueous polyurethane thickener) was 0.65 wt%, and the balance was water.

The method of arranging the coating material is the same as in Embodiment 1. The zero-cut viscosity of the coating material in this example was tested to be 1420.3 mPa·s (20 to 30 ° C).

In the same manner as in Example 1, the above coating material was sprayed on a PVC plastic skin to obtain a skin material after curing. The coating material was sprayed smoothly during the spraying process, and no phenomenon such as runny was observed.

The thickness of the coating in the above skin material was measured, and the results are shown in Table 1. It can be seen from Table 1 that the coating obtained in this example has a thickness ranging from 0.27 mm to 0.31 mm and a calculated pole difference of 0.04. Therefore, the thickness of the coating layer is uniform, which meets the tolerance requirement of the film thickness of the coating process of ±0.05.

The above-mentioned skin material is subjected to a cold knife weakening operation. After the operation is completed, the skin material and the instrument panel skeleton are foamed, and the foamed instrument panel assembly is subjected to a -30 ° C low temperature and 85 ° C high temperature air bag blasting test. Both the low temperature test and the high temperature test were qualified, especially in the low temperature explosion without cracking and splashing.

Example 6

This embodiment provides a coating material having a total mass content of 100%, including the following components:

Waterborne polyurethane (WBD-390, Shanghai Weiqi Chemical Co., Ltd.) 70wt%, color paste 20wt%, matting powder (matting powder TS100, Germany Degussa company) 1wt%, filming aid (dipropylene glycol methyl ether) 1.5wt %, defoamer (Fast301, Corning) 0.15wt%, wetting agent (acetylene glycol ethoxylate) 0.65wt%, thickener (aqueous polyurethane thickener) 0.2wt%, the rest is water .

The method of arranging the coating material is in accordance with Embodiment 2. The zero-cut viscosity of the coating material in this example was tested to be 4513.2 mPa·s (20 to 30 ° C).

In the same manner as in Example 1, the above coating material was sprayed on a PVC plastic skin to obtain a skin material after curing. The coating material was sprayed smoothly during the spraying process, and no phenomenon such as runny was observed.

The thickness of the coating in the above skin material was measured, and the results are shown in Table 1. As can be seen from Table 1, the coating obtained in this example has a thickness ranging from 0.27 mm to 0.31 mm and a calculated pole difference of 0.03. Therefore, the thickness of the coating layer is uniform, which meets the tolerance of the film thickness of the coating process of ±0.05.

The above-mentioned skin material is subjected to a cold knife weakening operation. After the operation is completed, the skin material and the instrument panel skeleton are foamed, and the foamed instrument panel assembly is subjected to a -30 ° C low temperature and 85 ° C high temperature air bag blasting test. Both the low temperature test and the high temperature test were qualified, especially in the low temperature explosion without cracking and splashing.

Example 7

This embodiment provides a coating material having a total mass content of 100%, including the following components:

Waterborne polyurethane (WBD-390, Shanghai Weiqi Chemical Co., Ltd.) 75wt%, color paste 16wt%, matting powder (matting powder TS100, Germany Degussa company) 0.6wt%, filming aid (dipropylene glycol methyl ether) 3wt %, defoamer (Fast301, Corning) 0.18wt%, wetting agent (acetylene glycol ethoxylate) 0.65wt%, thickener (aqueous polyurethane thickener) 0.35wt%, the rest is water .

The method of arranging the coating material is in accordance with Embodiment 2. The zero-cut viscosity of the coating material in this example was tested to be 4260.5 mPa·s (20 to 30 ° C).

In the same manner as in Example 1, the above coating material was sprayed on a PVC plastic skin to obtain a skin material after curing. The coating material was sprayed smoothly during the spraying process, and no phenomenon such as runny was observed.

The thickness of the coating in the above skin material was measured, and the results are shown in Table 1. It can be seen from Table 1 that the coating obtained in this example has a thickness ranging from 0.27 mm to 0.31 mm and a calculated pole difference of 0.04. Therefore, the thickness of the coating layer is uniform, which meets the tolerance requirement of the film thickness of the coating process of ±0.05.

The above-mentioned skin material is subjected to a cold knife weakening operation. After the operation is completed, the skin material and the instrument panel skeleton are foamed, and the foamed instrument panel assembly is subjected to a -30 ° C low temperature and 85 ° C high temperature air bag blasting test. Both the low temperature test and the high temperature test were qualified, especially in the low temperature explosion without cracking and splashing.

Comparative example 1

The PVC plastic skin which is completely consistent with the embodiment 1 is preheated in a heating furnace, and the preheating temperature and time are consistent with the first embodiment;

Take out the PVC plastic skin after the preheating is completed, fix it on the fixture, make the PVC plastic skin vertical suspension and the back side facing outward, then use the spray gun to spray the pure waterborne polyurethane coating (WBD-390, Shanghai Weiqi Chemical Co., Ltd. The film was uniformly sprayed on the surface of the balloon region and then allowed to cure at room temperature (about 25 ° C) to obtain a skin material.

Fig. 8 is a photograph of the pure waterborne polyurethane coating of the present comparative example before curing after spraying, and it can be seen from Fig. 8 that the coating material flows instantaneously after spraying. It can also be observed with the naked eye that the thickness of the coating obtained after curing is very uneven.

After the coating is cured, the cold knife weakening operation is performed. After the operation is completed, the skin material and the skeleton are foamed, and the foamed instrument panel assembly is subjected to a -30 ° C low temperature airbag blasting experiment.

Fig. 9 is a photo of a low-temperature airbag blasting experiment, in which it can be seen that the skin material is broken and the weakening line is opened unevenly. Therefore, the pure waterborne polyurethane coating failed to effectively improve the low temperature blasting performance of the PVC plastic skin.

Comparative example 2

This comparative example provides a coating material having a total mass content of 100%, including the following components:

Waterborne polyurethane (WBD-390, Shanghai Weiqi Chemical Co., Ltd.) 85wt%, color paste 5wt%, filming aid (dipropylene glycol methyl ether) 4wt%, defoamer (Fast301, Corning) 0.6wt%, run The wet agent (acetylene glycol ethoxylate) was 0.4% by weight, the thickener (aqueous polyurethane thickener) was 0.4% by weight, and the balance was water.

The method of arranging the coating material is the same as in Embodiment 1.

The coated coating material was sprayed on the surface of the PVC plastic skin according to the method of Example 1, and the cold knife weakening operation was performed, and then the -30 ° C low temperature airbag blasting experiment was performed, and the phenomenon of skin fragmentation occurred, so the low temperature blasting occurred. The experimental results were unsatisfactory and failed to improve the low temperature blasting performance of the PVC plastic skin.

Comparative example 3

The present comparative example provides a coating material having a total mass content of 100%, including the following components: water-based polyurethane (WBD-390, Shanghai Weiqi Chemical Co., Ltd.) 85 wt%, color paste 5 wt%, film forming auxiliary (dipropylene glycol methyl ether) 4wt%, defoamer (Fast301, Corning) 0.2wt%, wetting agent (acetylene glycol ethoxylate) 1wt%, thickener (aqueous polyurethane thickener) 0.4 Wt%, the rest is water.

The method of arranging the coating material is the same as in Embodiment 1.

The coated coating material was sprayed on the surface of the PVC plastic skin according to the method of Example 1, and the cold knife weakening operation was performed, and then the -30 ° C low temperature airbag blasting experiment was performed on the instrument panel assembly, and the skin cracking occurred. Phenomenon, occasionally there will be skin splash, so the results of low temperature blasting test failed, and failed to improve the low temperature blasting performance of PVC plastic skin.

Comparative example 4

This comparative example provides a coating material having a total mass content of 100%, including the following components:

Waterborne polyurethane (WBD-408, Shanghai Weiqi Chemical Co., Ltd.) 85wt%, color paste 5wt%, filming aid (dipropylene glycol methyl ether) 4wt%, defoamer (Fast301, Corning) 0.2wt%, run Wet agent (acetylene glycol ethoxylate) 1wt%, thickener (aqueous polyurethane thickener) 1.2wt%, The rest is water.

The method of arranging the coating material is the same as in Embodiment 1.

The coated coating material was sprayed on the surface of the PVC plastic skin according to the method of Example 1 and cured, and the thickness of the coating was unevenly observed by the naked eye, resulting in the skin material not being used normally.

Claims (16)

A coating material characterized by comprising the following mass percentage components:

The coating material according to claim 1, wherein the aqueous polyurethane has a viscosity of ≤ 1200 mPa·s. The coating material according to claim 1, wherein the film forming aid is dipropylene glycol methyl ether or dodecyl alcohol ester. The coating material according to claim 1, wherein the antifoaming agent is an aqueous antifoaming agent; the coloring paste is an aqueous coloring paste; and the thickening agent is an aqueous polyurethane thickening agent. The coating material according to claim 1, wherein the wetting agent is an acetylene glycol ethoxylate. The coating material according to any one of claims 1 to 5, further comprising a matting powder, the mass percentage of the matting powder in the coating material being 0.01% to 1%, and the average of the matting powder The particle size is 3 to 10 μm. The coating material according to claim 6, wherein the matting powder has a mass percentage of 0.5% to 1% in the coating material. The coating material according to claim 6 or 7, wherein the matting powder is silica. The method of configuring a coating material according to any one of claims 1-8, comprising: According to the formulation requirements, a color paste, a film forming aid, water, an antifoaming agent, a wetting agent and a thickener are sequentially added to the aqueous polyurethane, and uniformly mixed to obtain the coating material. The configuration method according to claim 9, comprising: According to the formulation requirements, a color paste, a matting powder, a film forming aid, water, an antifoaming agent, a wetting agent and a thickener are sequentially added to the aqueous polyurethane, and uniformly mixed to obtain the coating material. A method for spraying a PVC plastic skin, characterized in that the coating material according to any one of claims 1-8, comprising the following steps: Preheating the PVC plastic skin; The coating material is sprayed onto the surface of the preheated PVC plastic skin, which is then cured completely. The method according to claim 11, wherein the PVC plastic skin has a preheating temperature of 50 to 80 ° C and a preheating time of 3 to 15 minutes. The method of claim 11 wherein said coating material is cured at 15 to 80 °C. A skin material comprising at least a PVC plastic skin and a coating disposed on a surface of the PVC plastic skin, wherein the coating is formed by spraying by the method of any of claims 11-13. A skin material according to claim 14 wherein said coating has a thickness of from about 0.25 mm to about 0.35 mm. An automobile instrument panel having an instrument panel skin, characterized in that the instrument panel skin is made of the skin material according to claim 14 or 15, wherein the coating layer is disposed on the back of the PVC plastic skin .

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