Chameleon paint and its spraying process

Abstract

This invention discloses a chameleon paint and its spraying process. The chameleon paint comprises a base coat and a top coat. The base coat comprises resin, additives, solvent, dispersant, and color paste. The resin comprises the following weight percentages: 20%-30% polyurethane resin with a weight average molecular weight of 4K-7K, 12-16% acrylic resin, and 6-8% amino resin. The color paste mainly comprises the following weight percentages: 30-40% white paste, 2-6% purple paste, 0.1-1% bright red paste, and 0.1-0.5% black paste. The solvent comprises: 1-3% ethylene glycol hexyl ether and 1-4% dipropylene glycol methyl ether. The additive is BYK-346, with a weight percentage of 0.04-0.05%. The dispersant is water. This chameleon paint is a special automotive paint with unique properties and appearance. Its color changes with the viewing angle and light, presenting different hues and colors, creating a magical visual effect. It also has a high gloss, which reflects the light of the surrounding environment and enhances the color-changing effect.

Description

Technical Field

[0001] This invention belongs to the field of coating materials, specifically relating to a chameleon paint and its spraying process. Background Technology

[0002] Nowadays, cars have become a necessity in people's lives. However, many brands offer limited color options for new cars, making chameleon paint a solution to meet the diverse personalization needs of users. Color changing has a strong decorative effect, providing a three-dimensional and shimmering effect, especially appealing to those seeking fashion and innovation, and suiting the individualistic needs of young people. Because chameleon paint has high requirements for base coats, color coats, preparation, and application, most car color changes seen on the market are achieved through color-changing films. Color-changing films carry risks such as edge peeling, bubbling, and damage to the car's appearance in the short term. The chemical adhesive on the back can cause irreversible and serious damage to the original paint, affecting the car's appearance, and the gloss and saturation of the color are significantly inferior to the original paint.

[0003] To meet people's demand for personalized car exterior decoration, the inventor has developed a water-based chameleon paint called "Starry Purple". It boasts advantages such as high decorative value, high environmental friendliness, low consumption, rich and vibrant colors, and smooth color transitions. Summary of the Invention

[0004] The purpose of this invention is to provide a chameleon paint, its base coat, and its spraying process.

[0005] The chameleon paint of this invention, also known as a starry purple color-changing water-based car body paint, has been optimized and improved in terms of product ratio and spraying production process through the formulation of a scheme, experimental verification and data analysis, overcoming the problems of easy blooming and uneven color.

[0006] In one embodiment, a base coat for chameleon paint comprises a binder, additives, solvents, dispersants, and colorant, characterized in that:

[0007] The base material comprises the following resins by weight percentage: 20%-30% polyurethane resin with a weight average molecular weight of 4K-7K, 12-16% acrylic resin, and 6-8% amino resin.

[0008] The pigment is mainly composed of the following pigments by weight percentage:

[0009] White paste WM-1001-206 30-40%, Purple paste WM-5002A-206 2-6%, Crimson paste WM-6002-206 0.1-1%, Black paste WM-2002-206 0.1-0.5%.

[0010] The weight percentage is based on the total weight of the base coat.

[0011] Preferably, in the primer of the present invention, the polyurethane resin is HW-4261, and its weight-average molecular weight is 4K-7K. The acrylic resin is SETAQUA 6802, and the amino resin is CYMEL325.

[0012] Preferably, in the primer of the present invention, the solvent comprises 1-3% ethylene glycol hexyl ether and 1-4% dipropylene glycol methyl ether, the additive is BYK-346 with a weight percentage of 0.04-0.05%, and the dispersant is water with a weight percentage of 10-30%.

[0013] In a preferred embodiment, the base coat for chameleon paint of the present invention comprises the following components by weight percentage:

[0014]

[0015] On the other hand, the present invention provides a chameleon paint, comprising the aforementioned base coat, top coat, and clear coat.

[0016] The topcoat is composed of the following components in parts by weight:

[0017]

[0018] The varnish is composed of the following components by weight percentage:

[0019]

[0020] Preferably, in the chameleon paint of the present invention, the white paste, bright red paste, purple paste, and black paste are all from Huahui (Chongqing Huahui Coatings Co., Ltd.); the pearlescent powder is from Kuncai (Kuncai Pigment Co., Ltd.).

[0021] This invention also provides a chameleon paint spraying process, comprising the following steps:

[0022] 1) Perform routine treatment on the surface of the panel to be coated;

[0023] 2) Sand the panel to be coated;

[0024] 3) Spray the base coat, allow it to dry at room temperature, then flash dry at 80°C;

[0025] 4) Apply clear varnish and allow to dry at room temperature;

[0026] 5) Then bake at 140℃ for 25-35 minutes.

[0027] Preferably, in the above-described spraying process of the present invention, the surface drying time in step 3) is 10 min, the flash drying time is 10 min, the surface drying time in step 4) is 10 min, and the baking time in step 5) is 30 min.

[0028] Preferably, in the spraying process of the present invention, the sprayed paint film has the following characteristics: the clear varnish film thickness is 50 μm, the base coat film thickness is 8 μm, and the topcoat film thickness is 3 μm.

[0029] The Starry Purple Chameleon Paint of this invention is a special-effect automotive paint with unique properties and appearance. Its color changes with the viewing angle and lighting conditions, presenting different hues and colors to create a fantastical visual effect. The core technology of the chameleon paint involves adding a mixture of nano-sized titanium dioxide and aluminum powder pigments / mica pearlescent pigments coated with nano-titanium dioxide to the coating, enabling the coating to produce a mysterious and ever-changing angle-dependent color effect. That is, the coating displays different colors when viewed from different angles. Nano-titanium dioxide allows visible light to pass through while simultaneously blocking it to a certain extent, causing the transmitted light to reflect off the surfaces of the aluminum powder and titanium dioxide, thus producing different viewing angle effects.

[0030] The Starry Purple Chameleon Paint of this invention possesses high gloss, reflects ambient light, and enhances the color-changing effect. The angle and intensity of light affect the appearance of the painted surface, adding a unique artistic feel and visual appeal to the object's surface. Due to its special effects, the application of Starry Purple Chameleon Paint requires relatively high standards for the application environment and spraying techniques; correct coating techniques and environment are crucial to the final result. Overall, Starry Purple Chameleon Paint, with its unique color-changing effect and high gloss, provides a novel option for decoration and beautification. Attached Figure Description

[0031] Figure 1 This is the trend of color difference variation with film thickness in the first group of Examples 6 at 45°.

[0032] Figure 2 This is the second group of color difference trends with film thickness in Example 6 at 45°.

[0033] Figure 3 The images shown are comparison diagrams of the painted panels under light in Example 7. In Example 7, a is a chameleon painted panel obtained by spraying the base coat of Comparative Example 1, the top coat of Comparative Example 28, and the clear coat of Example 3. In Example 7, b is a chameleon painted panel obtained by spraying the base coat of Example 1, the top coat of Example 2, and the clear coat of Example 3. Detailed Implementation

[0034] The following examples are representative and are used to further understand and illustrate the essence of the present invention, but are not intended to limit the scope of the present invention.

[0035] Example 1: Base coat (primer)

[0036] The formula is shown in Table 1.

[0037] Table 1. Composition and Proportioning of Base Coating

[0038]

[0039]

[0040] The preparation process for the base coat is as follows:

[0041] 1. Add HW-4261 resin and color pastes WM-1001-206, WM-5002A-206, WM-6002-206, and WM-2002-206 in sequence, and stir at 300 rpm for 8-10 minutes.

[0042] 2. Add SETAQUA 6802 resin and stir at 1200 rpm for 30 minutes.

[0043] 3. Add the mixture of ethylene glycol hexyl ether and dipropylene glycol methyl ether in sequence, stir at 300 rpm for 5 minutes, and then add BYK-346 additive while stirring.

[0044] 4. Add CYMEL325 resin and stir at 900 rpm for 10 minutes.

[0045] 5. Add deionized water and stir for 10 minutes until well mixed to obtain the base coat.

[0046] Example 2 Topcoat

[0047] The formula for the topcoat is shown in Table 2.

[0048] Table 2. Topcoat Formulation

[0049]

[0050] Topcoat preparation process:

[0051] 1. Prepare B2 base material

[0052] 1.1 Add HW-4261 resin, SETAQUA 6802 resin, and CYMEL325 resin sequentially, and stir at 900 rpm for 8-10 minutes.

[0053] 1.2 Add the mixture of ethylene glycol hexyl ether and dipropylene glycol methyl ether in sequence, stir at 500 rpm for 5 minutes, and then add BYK-346 additive while stirring.

[0054] 1.3 Add deionized water and stir at 300 rpm for 10 minutes until well mixed to obtain B2 base material.

[0055] 2. Prepare pearlescent paste

[0056] 2.1 Take 20% by weight of the prepared B2 base material, add pearlescent powder KC19815D, stir at 1200 rpm for 30 minutes, and stir until uniform to obtain pearlescent paste.

[0057] 3. Add the remaining 80% of the B2 base material to the pearlescent paste and mix. Stir at 500 rpm for 10 minutes until well mixed to obtain the B2 topcoat.

[0058] Example 3: Clear Varnish

[0059] The varnish formula is shown in Table 3.

[0060] Table 3. Varnish Formulation Composition

[0061] 1780-65 acrylic resin 55％ Zhanxin Resin 91780-55 acrylic resin 30％ Zhanxin Resin S 138BB-70 Amino resins 5.0％ Zhanxin Resin basf-1130 Coating additives 1.5％ BASF basf-292 Coating additives 1.0％ BASF BYK-390 Coating additives 0.1％ Bik BYK-333 Coating additives 0.1％ Bik Butyl acetate diluent 3.0％ Shell methanol diluent 0.5％ Shell n-Butanol diluent 1.0％ Shell Amyl acetate diluent 2.8％ Shell

[0062] The preparation process for 2K varnish is as follows:

[0063] 1. Add paint additives 1130, 292, BYK-390, and BYK-333 in sequence;

[0064] 2. Add the diluents butyl acetate, methanol, n-butanol, and amyl acetate, and stir at 300 rpm for 8-10 minutes;

[0065] 3. Add 1780-65, 91780-5, and 138BB-70 resins while stirring, and stir at 900 rpm for 30 minutes until homogeneous to obtain 2K varnish.

[0066] Example 4: Starry Purple Chameleon Paint Spraying Process

[0067] The Starry Purple Chameleon Paint is made by spraying the base coat of Example 1, the topcoat of Example 2, and the clear coat of Example 3.

[0068] The spraying process for Starry Purple Chameleon Paint is as follows:

[0069] 1) Perform routine treatment on the surface of the intermediate coating test panel (commercially available);

[0070] 2) After sanding the intermediate coating test panel;

[0071] 3) Spray the base coat, allow it to dry at room temperature for 10 minutes, then flash dry at 80°C for 10 minutes;

[0072] 4) Spray B2 topcoat, allow it to dry at room temperature for 10 minutes, then flash dry at 80℃ for 10 minutes;

[0073] 5) Finally, spray with clear varnish and allow to dry at room temperature for 10 minutes.

[0074] 6) Bake in an oven at 140℃ for 30 minutes.

[0075] Example 5: Performance Test of Starry Purple Chameleon Paint

[0076] 1. The Influence of Pigments from Different Manufacturers on the Lab Color Space of Paint

[0077] The test compares the various performance data of the Starry Purple Chameleon Paint sprayed in Example 1 with those sprayed using the base paints of Comparative Examples 1-4 (formulas are shown in Table 4 below). The main focus is on the color difference of color pastes from different manufacturers at different angles.

[0078] Table 4. Formulations of base coats for Comparative Examples 1-4

[0079]

[0080]

[0081] Following the preparation method of the base coat in Example 1, chameleon paints of Comparative Examples 1-4 were prepared and sprayed according to the following process.

[0082] 1) Perform routine treatment on the surface of the intermediate coating test panel (commercially available);

[0083] 2) After sanding the intermediate coating test panel;

[0084] 3) Apply the base coat, allow it to dry at room temperature for 10 minutes, then flash dry at 80°C for 10 minutes.

[0085] 4) Finally, spray with clear varnish and allow to dry at room temperature for 10 minutes.

[0086] 5) Bake in an oven at 140℃ for 30 minutes. After cooling, test various performance indicators.

[0087] The color difference L, a, and b of the paint at angles of 25°, 45°, and 75° were tested using a colorimeter. (L represents lightness / darkness, A represents red / green value, and B represents blue / yellow value). The test results are shown in Table 5.

[0088] Table 5. Color Difference Test Results

[0089]

[0090]

[0091] The results in the table above indicate that:

[0092] Comparative Example 1 uses PNIER white paste, and color difference data shows that its L value (brightness), a value (red-green value), and b value (yellow-blue value) are all too high.

[0093] Comparative Example 2 used PNY purple paste, and color difference data showed that its L value (brightness) was low, its a value (red-green value) was low, and its b value (yellow-blue value) was high.

[0094] In Comparative Example 3, Yanbang Crimson Paste was used. Color difference data showed that its L value (brightness) was low, its a value (red-green value) was low, and its b value (yellow-blue value) was high.

[0095] Comparative Example 4 uses Yanbang black paste, and color difference data shows that its L value (brightness), a value (red-green value), and b value (yellow-blue value) are all low.

[0096] In summary, the base coat of Example 1 can achieve the standard Lab effect using color pastes produced by Huahui. Therefore, it is more suitable to use color pastes produced by Huahui.

[0097] 2. Pigment content experiment (highlighting the optimal pigment content)

[0098] 2.1 Investigating the effect of white pulp content on Lab.

[0099] In the formulations of Comparative Examples 5-9 (see Table 6 below), Huahui color paste was used. The main focus was on the effect of different contents of white color paste on Lab. The preparation of the base coat was carried out according to the method of Example 1, and the spraying was carried out according to the method of Example 5. The Lab of the paint was tested after spraying, and the results are shown in Table 7.

[0100] Table 6. Base coat formulations for Comparative Examples 5-9 and Example (1)

[0101]

[0102] Table 7. Lab color difference measurement results

[0103]

[0104]

[0105] The results in the table above indicate that:

[0106] In Comparative Example 5, the white pulp content was 29%. Color difference data showed that its L value (brightness), a value (red-green value), and b value (yellow-blue value) were all too low.

[0107] In Comparative Example 6, the white pulp content was 30%. Color difference data showed that its L value (brightness), a value (red-green value), and b value (yellow-blue value) were all low.

[0108] In Comparative Example 7, the white pulp content was 36%. Color difference data showed that its L value (brightness), a value (red-green value), and b value (yellow-blue value) were all too high.

[0109] In Comparative Example 8, the white paste content was 40%. Color difference data showed that its L value (brightness), a value (red-green value), and b value (yellow-blue value) were all too high.

[0110] In Comparative Example 9, the white paste content was 41%. Color difference data showed that its L value (brightness), a value (red-green value), and b value (yellow-blue value) were all too high.

[0111] In summary, the color difference data obtained when the white pigment content is 33% as in the example is closer to the standard Lab range. Therefore, a white pigment content of 33% is optimal.

[0112] 2.2 Investigating the effect of purple pulp content on Lab.

[0113] In the formulations of Comparative Examples 10-15 (see Table 8 below), Huahui pigments were used. The main focus was on investigating the effect of different contents of purple pigment on Lab. The preparation of the base coat followed the method of Example 1, and the spraying was carried out according to the method of Example 5. The Lab of the paint was tested after spraying, and the results are shown in Table 9.

[0114] Table 8. Base coat formulations for Comparative Examples 10-15 and Example (1)

[0115]

[0116] Table 9. Lab color difference measurement results

[0117]

[0118]

[0119] The results in the table above indicate that:

[0120] In Comparative Example 10, the purple paste content was 1%. Color difference data showed that its L value (brightness) was too high, its a value (red-green value) was too low, and its b value (yellow-blue value) was too high.

[0121] In Comparative Example 11, the purple paste content was 2%. Color difference data showed that its L value (brightness) was too high, its a value (red-green value) was too low, and its b value (yellow-blue value) was too high.

[0122] In Comparative Example 12, the purple paste content was 4%. Color difference data showed that its L value (brightness) was low, its a value (red-green value) was high, and its b value (yellow-blue value) was low.

[0123] In Comparative Example 13, the purple paste content was 5%. Color difference data showed that its L value (brightness) was low, its a value (red-green value) was high, and its b value (yellow-blue value) was low.

[0124] In Comparative Example 14, the purple paste content was 6%. Color difference data showed that its L value (brightness) was low, its a value (red-green value) was high, and its b value (yellow-blue value) was low.

[0125] In Comparative Example 15, the purple paste content was 7%. Color difference data showed that its L value (brightness) was too low, its a value (red-green value) was too high, and its b value (yellow-blue value) was too low.

[0126] In summary, when the optimal content of purple pigment is 3% as in Example 1, the color difference data is within the standard requirement range and is quite close to the standard value. Therefore, the optimal content of purple pigment is 3%.

[0127] 2.3 Experiment on the content of bright red pulp

[0128] In the formulations of Comparative Examples 16-21 (see Table 10 below), Huahui pigments were used. The main focus was on the effect of different contents of bright red pigment on Lab. The preparation of the base coat followed the method of Example 1, and the spraying was carried out according to the method of Example 5. The Lab of the paint was tested after spraying, and the results are shown in Table 11.

[0129] Table 10. Formulations of base coats for Comparative Examples 16-21

[0130]

[0131] Table 11. Lab color difference measurement results

[0132]

[0133]

[0134] The results in Table 11 show that:

[0135] In Comparative Example 16, the content of bright red paste was 0.05%. Color difference data showed that its L value (brightness) was too high, its a value (red-green value) was too low, and its b value (yellow-blue value) was too low.

[0136] In Comparative Example 17, the content of bright red paste was 0.1%. Color difference data showed that its L value (brightness) was too high, its a value (red-green value) was too low, and its b value (yellow-blue value) was too low.

[0137] In Comparative Example 18, the content of bright red paste was 0.3%. Color difference data showed that its L value (brightness) was too high, its a value (red-green value) was too low, and its b value (yellow-blue value) was too low.

[0138] In Comparative Example 19, the content of bright red paste was 0.7%. Color difference data showed that its L value (brightness) was low, its a value (red-green value) was high, and its b value (yellow-blue value) was high.

[0139] In Comparative Example 20, the content of bright red paste was 1.0%. Color difference data showed that its L value (brightness) was low, its a value (red-green value) was high, and its b value (yellow-blue value) was high.

[0140] In Comparative Example 21, the content of bright red paste was 1.1%. Color difference data showed that its L value (brightness) was too low, its a value (red-green value) was too high, and its b value (yellow-blue value) was too high.

[0141] In summary, when the optimal content of the bright red pigment is 0.5% as in Example 1, the color difference data is within the standard requirement range and is relatively close to the standard value. Therefore, a content of 0.5% for the bright red pigment is optimal.

[0142] 2.4 Black Paste Content Experiment

[0143] In the formulations of Comparative Examples 22-27 (see Table 12 below), Huahui color paste was used. The main investigation focused on the effect of different contents of black paste on Lab. The preparation of the base coat followed the method of Example 1, and the spraying was carried out according to the method of Example 5. The Lab of the paint was tested after spraying, and the results are shown in Table 13.

[0144] Table 12. Basecoat Formulations for Comparative Examples 22-27

[0145]

[0146] Table 13. Lab color difference measurement results

[0147]

[0148]

[0149] in conclusion

[0150] In Comparative Example 22, the black paste content was 0.05%. Color difference data showed that its L value (brightness), a value (red-green value), and b value (yellow-blue value) were all too high.

[0151] In Comparative Example 23, the black paste content was 0.1%. Color difference data showed that its L value (brightness), a value (red-green value), and b value (yellow-blue value) were all too high.

[0152] In Comparative Example 24, the black paste content was 0.3%. Color difference data showed that its L value (brightness), a value (red-green value), and b value (yellow-blue value) were all low.

[0153] In Comparative Example 25, the black paste content was 0.4%. Color difference data showed that its L value (brightness), a value (red-green value), and b value (yellow-blue value) were all low.

[0154] In Comparative Example 26, the black paste content was 0.5%. Color difference data showed that its L value (brightness), a value (red-green value), and b value (yellow-blue value) were all low.

[0155] In Comparative Example 27, the black paste content was 0.6%. Color difference data showed that its L value (brightness), a value (red-green value), and b value (yellow-blue value) were all too low.

[0156] In summary, when the black paste content is 0.2% as in Example 1, the color difference data is within the standard requirement range and is relatively close to the standard value. Therefore, a black paste content of 0.2% is most suitable.

[0157] 3. Experiment on the types of pearlescent powder in the topcoat

[0158] The effect of pearlescent powder from different manufacturers on the color difference of paint Lab was investigated. The topcoats of Comparative Examples 28-30 and Example 2 (formulas are shown in Table 14) were prepared according to the method of Example 2.

[0159] The base coat used in Example 2 and Comparative Examples 28-30 all adopted the formulation and preparation process of Example 1.

[0160] The varnishes used in Example 2 and Comparative Examples 28-30 all adopted the formulation and preparation process of Example 3.

[0161] Its spraying process is as follows:

[0162] 1) Perform routine treatment on the surface of the intermediate coating test panel (commercially available);

[0163] 2) After sanding the intermediate coating test panel;

[0164] 3) Then spray B1 base coat, allow to dry at room temperature for 10 minutes, then flash dry at 80℃ for 10 minutes;

[0165] 4) Spray B2 topcoat, allow it to dry to the touch at room temperature for 15 minutes, then flash dry at 80°C for 10 minutes.

[0166] 5) Finally, spray with clear varnish and allow to dry at room temperature for 10 minutes.

[0167] 6) Bake in an oven at 140℃ for 30 minutes. After cooling, test the index data (Lab). The results are shown in Table 15.

[0168] Table 14. Topcoat (Coating 2) Formulations for Comparative Examples 28-30

[0169]

[0170] Table 15. Lab color difference measurement results

[0171]

[0172] The results in the table above indicate that:

[0173] Comparative Example 28 used HeCai Chameleon Pearl Powder. Color difference data showed that its L value (brightness / darkness) was too high, its a value (red / green value) was too high, and its b value (yellow / blue value) was too low.

[0174] Comparative Example 29 used Belladonna chameleon pearl powder. Color difference data showed that its L value (brightness) was low, its a value (red-green value) was low, and its b value (yellow-blue value) was high.

[0175] Comparative Example 30 used Cloud Bead Chameleon Pearl Powder. Color difference data showed that its L value (brightness) was too high, its a value (red-green value) was too low, and its b value (yellow-blue value) was too high.

[0176] The color difference data of the chameleon pearl light powder used in Example 2 shows that its L value (brightness), a value (red-green value), and b value (yellow-blue value) are closest to the standard values.

[0177] In conclusion, chameleon atomizing powder produced by manufacturers other than Kuncai cannot meet the color difference requirements of customers. Therefore, Kuncai chameleon atomizing powder is the most suitable choice.

[0178] 4. Experiment on pearlescent powder content in topcoat (screening for the optimal pearlescent powder content)

[0179] The effect of the content of pearlescent powder from Kuncai manufacturer in the topcoat on the Lab color difference of the paint was investigated. Comparative Examples 31-40 and the topcoat of Example 2 (formulas are shown in Table 16) were used. The topcoat was prepared according to the method of Example 2.

[0180] The base coat used in Example 2 and Comparative Examples 31-40 all adopted the formulation and preparation process of Example 1.

[0181] The varnishes used in Example 2 and Comparative Examples 31-40 all adopted the formulation and preparation process of Example 3.

[0182] The paint was applied according to the method in Example 4. The Lab color difference of the paint was tested, and the results are shown in Table 17.

[0183] Table 16. Topcoat mixing ratios for Comparative Examples 31-40

[0184]

[0185] Table 17. Lab color difference measurement results

[0186]

[0187]

[0188] The results in the table above indicate that:

[0189] In Comparative Example 31, the pearlescent powder content was 0.75%. Color difference data showed that its 25° and 45°L values ​​(brightness) were too high, its 45°a value (red-green value) was too low, and its 25°b value (yellow-blue value) was too low.

[0190] In Comparative Example 32, the pearlescent powder content was 1.00%, and the color difference data showed that its 25° and 45° L values ​​(brightness) were too high.

[0191] In Comparative Example 33, the pearlescent powder content was 1.25%, and the color difference data showed that its 25°L value (brightness) was too high.

[0192] In Comparative Example 34, the pearlescent powder content was 1.5%. Color difference data showed that its 25°L value (brightness) was low and its 25°b value (yellow-blue value) was high.

[0193] The pearlescent powder content in Comparative Example 35 was 1.75%, and the color difference data showed that its 75° and 45° b values ​​(yellow-blue values) were low.

[0194] In Comparative Example 36, the pearlescent powder content was 2.00%. Color difference data showed that its 25°L value (brightness) was too high and its 25°b value (yellow-blue value) was too low.

[0195] In Comparative Example 37, the pearlescent powder content was 2.50%. Color difference data showed that its 25°L value (brightness) was low and its 25°b value (yellow-blue value) was high.

[0196] In Comparative Example 38, the pearlescent powder content was 2.75%. Color difference data showed that its 25°L value (brightness) was too high, its 45°a value (red-green value) was too low, and its 45° and 75°b values ​​(yellow-blue value) were too high.

[0197] In Comparative Example 39, the pearlescent powder content was 3.00%. Color difference data showed that its 25° and 45°L values ​​(brightness) were too high, its 25°a value (red-green value) was too low, and its 45° and 75°b values ​​(yellow-blue value) were too high.

[0198] In Comparative Example 40, the pearlescent powder content was 3.25%. Color difference data showed that its 25°, 45°, and 75°L values ​​(brightness) were too high, its 25° and 45°a values ​​(red-green values) were too low, and its 25°, 45°, and 75°b values ​​(yellow-blue values) were too high.

[0199] In summary, when the optimal content of pearlescent powder is 2.25% in the example, the color difference data is within the standard requirement range and is relatively close to the standard value.

[0200] Example 6: The effect of topcoat leveling time on color difference

[0201] The paint viscosity was adjusted to 48s and the temperature to 20℃. A control was created by spraying the original component base coat. The leveling time of the topcoat was extended to improve its leveling effect. All other components remained the same. A chameleon-colored panel obtained by spraying the base coat from Example 1, the topcoat from Example 2, and the clear coat from Example 3, with a leveling time of 15 minutes for the topcoat, was compared with a comparative chameleon-colored panel obtained by spraying with different leveling times.

[0202] Spraying process: Prepare a test panel for the intermediate coating. After sanding, spray the base coat, allowing sufficient time for both the base coat and top coat to naturally level (10 min), followed by flash drying at 80℃ for 10 min. Then spray the top coat, allowing for natural leveling (15 min), followed by flash drying at 80℃ for 10 min. Finally, spray the clear coat, allowing for natural leveling (10 min), followed by drying at 140℃ for 30 min. The top coat formulation is shown in Table 18 below.

[0203] Table 18. Surface coating formulations and leveling times for Comparative Examples 41-43 and Example 6

[0204]

[0205]

[0206] The obtained painted panels were compared under light, and the results are shown in the figure. Figure 3 In the figures, a is the chameleon paint panel obtained by spraying Comparative Example 41, b is the chameleon paint panel obtained by spraying Example 6, c is the chameleon paint panel obtained by spraying Comparative Example 42, and d is the chameleon paint panel obtained by spraying Comparative Example 43. It can be seen that the chameleon paint with a leveling time of 15 minutes is significantly glossier than the topcoat of the comparative examples.

[0207] Example 7: The Influence of Base Coating Film Thickness on Color Difference

[0208] While keeping the clear coat film thickness constant, and also keeping the base coat film thickness constant, we designed corresponding gradients, compared them, studied the effect of film thickness on color difference, and explored the film thickness data that can achieve the best effect.

[0209] The base coat from Example 1, the top coat from Example 2, and the clear coat from Example 3 were used for spraying. The viscosity of the paint was adjusted to 48s and the temperature to 20°C.

[0210] Spraying process: Prepare 11 intermediate coating test panels. After sanding, spray different thicknesses of base coat on each panel, allow them to level naturally for 10 minutes, and flash dry at 80℃ for 10 minutes. Finally, spray a clear coat with a film thickness of 50 μm, allow it to level naturally for 10 minutes, and dry at 140℃ for 30 minutes. The formulations of the primers for Comparative Examples 44-53 and Example 7 are shown in Table 19 below.

[0211] Table 19. Formulations of the primers for Comparative Examples 44-53 and Example 7

[0212]

[0213] Experimental Results: The trend of color difference at 45° with film thickness is as follows: Figure 1 As shown in (ad), the values ​​of ΔL, Δa, and Δb are best when they are in the middle of the upper and lower limits, and the smaller ΔE is, the better. The trend graph shows that when the clear coat film thickness is 50μm, the base coat film thickness is 8μm, resulting in the best color difference performance and the best color change effect.

[0214] Example 8: The Influence of Topcoat Film Thickness on Color Difference

[0215] While keeping the clear coat film thickness constant, and also keeping the topcoat film thickness constant, design corresponding gradients, compare them, study the effect of film thickness on color difference, and explore film thickness data that can achieve the best effect.

[0216] The base coat from Example 1, the top coat from Example 2, and the clear coat from Example 3 were used for spraying. The viscosity of the paint was adjusted to 48s and the temperature to 20°C.

[0217] Spraying process: Prepare 8 intermediate coating test panels. After sanding, spray an 8μm thick base coat, allow it to level naturally for 10 minutes, and flash dry at 80℃ for 10 minutes. Then spray topcoats of different thicknesses, allow them to level naturally for 15 minutes, and flash dry at 80℃ for 10 minutes. Finally, spray a clear varnish with a film thickness of 50μm, allow it to level naturally for 10 minutes, and dry at 140℃ for 30 minutes. The formulations of the topcoats for Comparative Examples 54-60 and Example 8 are shown in Table 20 below.

[0218] Table 20. Formulations of the topcoat for Comparative Examples 54-60 and Example 8

[0219]

[0220] Experimental Results: The trend of color difference at 45° with film thickness is as follows: Figure 2 As shown in (ad), the values ​​of ΔL, Δa, and Δb are best when they are in the middle of the upper and lower limits, and the smaller ΔE is, the better. The trend chart shows that when the clear coat film thickness is 50μm, the base coat film thickness is 8μm, and the topcoat film thickness is 3μm, the color difference performance is the best and the color change effect is the best.

[0221] Experimental results show that the base coat and top coat combination coating of the present invention, namely the combination of the base coat of Example 1 and the top coat of Example 2 with specific formulations, exhibits good color difference data after spraying when the base coat film thickness is 8μm, the top coat film thickness is 3μm, and the top coat leveling time is 15min. The color change is significant, the pearlescent distribution is relatively uniform, there is no blooming, the color is bright, the gloss is bright, and the color-changing effect is excellent, obvious, and prominent. Compared with the comparative example combination coating, it shows significant superiority in color-changing effect and appearance.

[0222] Finally, it should be noted that the abbreviations of the suppliers of raw materials and reagents mentioned in this article correspond to the full names of the suppliers, as shown in Table 21 below.

[0223] Table 21. Supplier Abbreviation Correspondence Table

[0224]

Claims

1. A chameleon paint comprising a base coat and a top coat, wherein the base coat comprises the following components by weight percentage: Polyurethane resin HW-4261 ---------25% Acrylic resin SETAQUA 6802----14% Amino resin CYMEL325 ----------7% Additive BYK-346 0.05% Solvent: Ethylene glycol hexyl ether ------------ 3% Solvent: dipropylene glycol methyl ether ---------- 3% Dispersion medium: deionized water 11.25% White paste WM-1001-206---------33% Purple paste WM-5002A-206 -------- 3% Bright red paste WM-6002-206-------0.5% Black paste WM-2002-206---------0.2%; The topcoat is composed of the following components in parts by weight: Polyurethane resin HW-4261 - 31.44% Acrylic resin SETAQUA 6802 ---- 17.60% Amino resin CYMEL325 ---------- 8.80% Additive BYK-346 0.06% Solvent: Ethylene glycol hexyl ether ----------- 3.77% Solvent: Dipropylene glycol methyl ether --------- 3.77% Dispersion medium: deionized water 32.31% Pearlescent powder KC19815D-----------2.25%, The base coat film thickness is 8µm, and the top coat film thickness is 3µm.

2. The chameleon paint of claim 1, further comprising a varnish, said varnish being composed of the following components by weight percentage: Acrylic resin 1780-65---------55% Acrylic resin 91780-55 - 30% Amino resin 138BB-70 ---------- 5.0% Coating additive BASF 1130 ----------1.5% Coating additive BAF 292 -----------1.0% Coating additives BYK 390 ------------ 0.1% Coating additives BYK 333 ------------ 0.1% Diluent: Butyl acetate ------------ 3.0% Diluent: Methanol ----------------- 0.5% Diluent: n-Butanol 1.0% Diluent: Amyl acetate 2.8%.

3. A spraying process for chameleon paint, wherein the paint is the chameleon paint of claim 2, comprising the following steps: 1) Perform routine treatment on the surface of the panel to be coated; 2) Sand the panel to be coated; 3) Spray the base coat of claim 2, allow it to dry at room temperature, and then flash dry at 80°C; 4) Apply the topcoat of claim 2, allow it to dry at room temperature, and then flash-dry at 80°C. 5) Finally, spray the clear varnish of claim 2 and allow it to dry at room temperature; 6) Then bake at 140℃ for 25-35 minutes. The clear varnish film thickness is 50µm, the base coat film thickness is 8µm, and the topcoat film thickness is 3µm.

4. In the spraying process as described in claim 3, the surface drying time in step 3) or 4) is 10 min, and the flash drying time is 10 min.

5. The spraying process as described in claim 3, wherein the surface drying time in step 5) is 10 min and the baking time in step 6) is 30 min.

Images