CN117990663A

CN117990663A - Method for testing reliability of full life cycle of water paint

Info

Publication number: CN117990663A
Application number: CN202311783761.4A
Authority: CN
Inventors: 阳铭铭; 李会宁; 陈仕箐; 刘淑仪
Original assignee: Zhaoqing Rivers High Tech Materials Co ltd
Current assignee: Zhaoqing Rivers High Tech Materials Co ltd
Priority date: 2023-12-22
Filing date: 2023-12-22
Publication date: 2024-05-07

Abstract

The invention provides a method for testing the reliability of the whole life cycle of water paint, which can accurately detect the influence of different materials, different process flows, different proportioning components and different spraying methods on the service life of a paint film; and detecting different factors under different conditions, and detecting factors influencing the service life of the paint film.

Description

Method for testing reliability of full life cycle of water paint

Technical Field

The invention relates to the field of detection of water paint, in particular to a method for testing the reliability of the whole life cycle of water paint.

Background

Along with the development of industrial technology, in order to improve the appearance, the service life and the like of parts, paint films are sprayed on the surfaces of engineering machinery, rail transit and automobile parts, and the water paint is harmless to human bodies, does not pollute the environment, is plump, crystal clear and flexible, has the characteristics of water resistance, wear resistance, aging resistance, yellowing resistance, quick drying, convenient use and the like, and is gradually accepted by consumers in recent years; the service life standard of the paint film is 15 years of service life or 660 ten thousand kilometers of vehicle running is met; however, the time for the appearance of the water paint is short and is not enough for the existing standard to judge; for this purpose, the water-based paint needs to be subjected to an aging resistance test and a salt spray resistance test.

Patent literature with publication number of CN202110566050.6 and publication day of 2021.8.27 discloses a bi-component aqueous hydroxyl acrylic polyurethane finish emulsion and a preparation method thereof; the existing ageing resistance test and salt spray resistance test are carried out by taking a paint film as a whole, and the comparison detection is not carried out on different materials, different process flows, different proportioning components or different spraying methods of the paint film composition, so that the influence of different materials, different process flows, different proportioning components and different spraying methods on the service life of the paint film can not be accurately detected.

Disclosure of Invention

The invention provides a method for testing the reliability of the whole life cycle of water paint, which can accurately detect the influences of different materials, different process flows, different proportioning components and different spraying methods on the service life of a paint film.

In order to achieve the above purpose, the technical scheme of the invention is as follows: the method for testing the reliability of the whole life cycle of the water paint comprises a preparation process detection method of a paint film.

The preparation process detection method of the paint film comprises the following steps:

S1, paint films with different dry film thicknesses are prepared by the same paint matching process; carrying out ageing resistance test on paint films with the same dry film thickness by different paint preparation processes; detecting the gloss, the extinction ratio and the color difference values of paint films of different paint preparation processes; detecting the gloss, the extinction rate and the color difference values of paint films with different thicknesses; the aging resistance difference between the paint films of different paint preparing processes and between the paint films of different thicknesses is tested.

S2, performing performance test on the priming paint with different drying temperatures, the middle painting with different drying temperatures and the finishing paint with different drying temperatures; and testing the performance difference among the priming paint with different drying temperatures, the middle coating with different drying temperatures and the finishing paint with different drying temperatures.

S3, detecting glossiness of the intermediate paint sprayed on the light plate, the primer or the putty and with different thickness; detecting glossiness of the paint sprayed on the light plate, the primer or the putty and having different drying temperatures; the difference in gloss of the basecoat sprayed on the gloss plate, primer or putty was tested for different thicknesses and different drying temperatures.

S4, carrying out water resistance and aging resistance tests on the paint film sprayed with the middle coating and the paint film without the middle coating; testing the difference in water resistance between the coating with the middle coating and the coating without the middle coating; the difference in aging resistance between the coating with the middle coating and the coating without the middle coating was tested.

S5, carrying out aging resistance test on paint films with different spraying methods, and detecting the change of gloss and color difference values of the paint films with different spraying methods; carrying out aging resistance test on different paint films with the same spraying method, and detecting the change of gloss and color difference values of the different paint films with the same spraying method;

Salt spray resistance tests are carried out on the priming paint and the paint film with different spraying methods, and the difference of gloss and color difference values of the priming paint and the paint film with different spraying methods is detected; and (3) carrying out salt spray resistance test on different primer and paint films with the same spraying method, and detecting whether the foaming phenomenon and the rusting phenomenon of the different primer and paint films sprayed by the same spraying method are different.

And S6, determining paint film aging test data and salt spray resistance test data according to the bubble phenomenon and the rust phenomenon of the paint film.

According to the method, whether the ageing resistance of the paint film is influenced by different paint preparation processes is detected by testing the ageing resistance difference between the paint films of different paint preparation processes; and detecting whether the ageing resistance of the paint films is influenced by the different thicknesses by testing the ageing resistance difference between the paint films with the different thicknesses.

Testing performance differences among the priming paint with different drying temperatures, the middle paint with different drying temperatures and the finish paint with different drying temperatures; and detecting whether different drying temperatures affect the performances of the primer, the middle coating and the finishing coating.

The difference of gloss of the middle coating sprayed on the light plate, the primer or the putty is tested by the middle coating with different thickness and different temperature; and detecting whether the glossiness of the middle paint sprayed on the light plate is influenced by different thicknesses and different drying temperatures. And detecting whether the glossiness of the primer sprayed by the middle coating is influenced by different thicknesses and different drying temperatures. And detecting whether the glossiness of the spray coating of the intermediate paint on the putty is influenced by different thicknesses and different drying temperatures.

By testing the difference in water resistance between the coating with the mid-coat and the coating without the mid-coat; it was examined whether the presence or absence of a mid-coat has an effect on the water resistance of the paint film. By testing the difference in aging resistance between the coating with the middle coating and the coating without the middle coating; and detecting whether the intermediate coating has influence on the ageing resistance of the paint film.

Carrying out aging resistance test on different paint films of the spraying method to obtain gloss and color difference values of the paint films under different spraying methods, and comparing the gloss of the paint films under the two spraying methods with the color difference values of the paint films under the two spraying methods; whether the ageing resistance of the paint film is changed or not under different spraying methods is detected, and meanwhile, the influence factors of the paint film ageing test and the finally satisfied conditions are determined for the same spraying method of different paint films, so that the influence of various paint films and different spraying methods on the specific ageing test can be conveniently predicted.

Salt spray resistance tests are carried out on different priming paint of the spraying method, so that foaming and rusting phenomena of the priming paint under different spraying methods are obtained; and comparing the foaming phenomenon of the primer under the two spraying methods, the rusting phenomenon of the primer under the two spraying methods, and detecting whether the salt spray resistance of the primer under different spraying methods is changed. Meanwhile, the influence factors and the finally satisfied conditions of salt spray resistance tests of the paint film and the primer are determined for different paint films by the same spraying method, so that the influence of various paint films and different spraying methods on the salt spray resistance test can be conveniently predicted, and the primer can also have a certain influence on the salt spray resistance test, so that the test of the primer is considered in the test process, and the reliability of the whole test process is ensured.

Drawings

FIG. 1 is a graph showing the effect of the air-jet coating method of an embodiment of the present invention after a 1500-hour aging test is performed on a water-based paint (RAL 9005 black). FIG. 2 is a graph showing the effect of the airless spray method of this invention after a 1500h aging test is performed on a water-based paint (RAL 9005 black). Fig. 3 is a graph showing the effect of the air-jet coating method of another embodiment of the present invention after a water paint (RAL 9005 black) is formed and subjected to a 1500h salt spray resistance test. Fig. 4 is a graph showing the effect of an airless spray method of this invention after a water paint (RAL 9005 black) is formed and subjected to a salt spray resistance test for 1500 hours. Fig. 5 is a graph showing the effect of the air-jet coating method of another embodiment of the present invention after a water-based paint (RAL 9006 silver) is subjected to a 1500h aging resistance test. Fig. 6 is a graph showing the effect of a non-air spray method of forming a water-based paint (RAL 9006 silver) for 1500h of ageing resistance testing according to a further embodiment of the present invention. Fig. 7 is a graph showing the effect of the air-jet coating method of another embodiment of the present invention after a 1500-hour salt spray test is performed on aqueous paint (RAL 9006 silver). Fig. 8 is a graph showing the effect of a airless spray method of this invention after a water paint (RAL 9006 silver) was formed and tested for salt spray resistance for 1500 hours.

Detailed Description

The invention is described in further detail below with reference to the drawings and the detailed description.

The method for testing the reliability of the whole life cycle of the water paint comprises a preparation process detection method of a paint film.

Detecting whether different paint preparation processes have influence on ageing resistance of paint films or not by testing ageing resistance difference among paint films of different paint preparation processes; and detecting whether the ageing resistance of the paint films is influenced by the different thicknesses by testing the ageing resistance difference between the paint films with the different thicknesses.

S1 specifically comprises the following steps:

S1.1, setting a first experimental group of a process, a second experimental group of the process, a third experimental group of the process and a fourth experimental group of the process; the first experiment group and the second experiment group have the same paint preparing process, and the dry film thicknesses of the paint are different; the third experiment group of the process and the fourth experiment group of the process are the same in paint preparing process, and the dry film thicknesses of the paint are different; the first experiment group of the process and the third experiment group of the process are different in paint preparing process, and the dry film thickness of the paint is the same; the process second experimental group and the process fourth experimental group are different in paint preparation process, and the dry film thickness of the paint is the same.

S1.2, irradiating a first experiment group, a second experiment group, a third experiment group and a fourth experiment group by using a UVB lamp and a xenon lamp respectively.

S1.3, detecting gloss, extinction ratio and chromatic aberration values of paint films of different paint preparation processes; detecting the gloss, the extinction rate and the color difference values of paint films with different thicknesses; the aging resistance difference between the paint films of different paint preparing processes and between the paint films of different thicknesses is tested.

According to the method, whether the ageing resistance of the paint film is influenced by different thicknesses in a paint preparation process is detected by comparing the first experimental group with the second experimental group; comparing the third experimental group with the fourth experimental group, and detecting whether the ageing resistance of the paint film is influenced by different thicknesses in another paint preparation process; and comparing the first experimental group with the third experimental group to detect whether different effects on ageing resistance of the paint film are generated when the thickness of the paint film is the same.

In this example, process A1, experimental group a: mixing paint and curing agent, stirring uniformly, adding water, stirring uniformly, and spraying the paint film with the following requirements: the dry film of the base coat is 80 mu m, and the dry film of the varnish is 80 mu m.

Process second experimental group A2: mixing paint and curing agent, stirring uniformly, adding water, stirring uniformly, and spraying the paint film with the following requirements: the dry film of the base paint is 20-30 mu m, and the dry film of the varnish is 50 mu m.

Process third experimental group B1: adding the paint, the curing agent and water into a container, and stirring uniformly, wherein the paint film requirements during spraying are as follows: the dry film of the base coat is 80 mu m, and the dry film of the varnish is 80 mu m.

Process fourth experimental group B2: adding the paint, the curing agent and water into a container, and stirring uniformly, wherein the paint film requirements during spraying are as follows: the dry film of the base paint is 20-30 mu m, and the dry film of the varnish is 50 mu m.

The anti-aging test was carried out as specified in annex C of GB/T14522-2008 "type 7 exposure cycle".

Table 1.1 is a table of the aging resistance test data recorded for the first experimental group A1 of the process by UVB lamp.

TABLE 1.1

Table 1.2 is a table of data recorded for the ageing resistance test performed on the first experimental group A1 of the process by the xenon lamp.

TABLE 1.2

Table 1.3 is a table of the aging resistance test data recorded for the UVB lamp for the second experimental group A2 of the process.

TABLE 1.3

Table 1.4 is a table of data recorded for the aging resistance test performed on the second experimental group A2 of the process by the xenon lamp.

TABLE 1.4

Table 1.5 is a table of data recorded for the aging resistance test performed by UVB lamp on process third experimental group B1.

TABLE 1.5

Table 1.6 is a table of data recorded for the aging resistance test performed on the third experimental group B1 of the process by the xenon lamp.

TABLE 1.6

Table 1.7 is a table of the aging resistance test data recorded for the UVB lamp for the fourth experimental group B2 of the process.

TABLE 1.7

Table 1.8 is a table of data recorded for the ageing resistance test performed on the fourth experimental group B2 of the process by the xenon lamp.

TABLE 1.8

To sum up, in the experiment of the group A, the paint and the curing agent are mixed firstly, water is added after the mixture is stirred uniformly, the aging resistance is tested for 1500 hours by a UVB lamp, the paint film has almost no color change and no light loss (delta E is less than 2.0 and the light loss rate is less than 5 percent) when the paint film has different film thicknesses, and the two experiments have almost no difference.

In the experiment of the group A, firstly, the paint and the curing agent are mixed, water is added after the mixture is stirred uniformly, the ageing resistance is tested for 1500 hours by a xenon lamp, when the varnish has different film thicknesses, the color change of the two groups of experiments is close, and delta E is smaller than 2.0; the color change is not obvious, but the film thickness of the paint film has smaller light loss rate which is less than 15 percent.

In the experiment of group B, paint, curing agent and water are added into a container and stirred uniformly, the ageing resistance of the B21 lamp is tested for 1500 hours, when the thickness of the varnish is different, the paint film has almost no color change and no light loss (delta E is less than 2.0 and the light loss rate is less than 5 percent), and the two experiments have almost no difference

In the experiment of the group B, paint, a curing agent and water are added into a container, and then uniformly stirred, wherein the ageing resistance is tested for 1500 hours by a xenon lamp, when the thickness of the varnish is different, the color of the two groups of experiments is similar, and delta E is smaller than 2.0; the color change is not obvious, but the film thickness of the paint film has smaller light loss rate which is less than 15 percent.

The color change and the light loss rate of the group A are slightly larger than those of the group B, but are not obvious, the aging resistance is 1500h, and both the group B lamp and the xenon lamp can meet the requirements of the middle vehicle (delta E is less than or equal to 3.0).

In conclusion, the ageing resistance of the paint film is hardly influenced by different paint preparation modes; the thickness of the paint film has almost no influence on the ageing resistance of the paint film.

The finish paint is a first finish paint, a second finish paint or a third finish paint; the first finishing paint, the second finishing paint or the third finishing paint is independently coated on the surface of the middle paint for use; the paint film comprises more than three kinds, and the first kind is: the primer, the basecoat and the first topcoat coat the formed film. The second is: the primer, the middle coat and the second topcoat coat the formed film. The third is: the primer, the middle coat and the third coat the formed film.

S2 specifically comprises the following steps:

S2.1, setting a fifth experimental group, a sixth experimental group, a seventh experimental group, an eighth experimental group and a ninth experimental group; the fifth experimental group of the process comprises more than two drying temperatures of the primer; the sixth experimental group of the process comprises more than two drying temperatures of the middle coating; the seventh experimental group of the process comprises more than two drying temperatures of the first finishing coat; the eighth experimental group of the process comprises two drying temperatures above the second finish paint; the ninth experimental group of the process includes two drying temperatures above the third topcoat.

S2.2, detecting performance differences among the priming paint with different drying temperatures, the middle paint with different drying temperatures, the first surface paint with different drying temperatures, the second surface paint with different drying temperatures and the third surface paint with different drying temperatures.

The method is characterized in that more than two types of temperature data are compared; in a fifth experimental group of the process, detecting whether different drying temperatures have influence on the performance of the primer; in a sixth experimental group of the process, detecting whether different drying temperatures affect the performance of the centering paint; in a seventh experimental group of the process, detecting whether different drying temperatures have influence on the performance of the first finish paint; in an eighth experimental group of the process, detecting whether different drying temperatures affect the performance of the second finish paint; in a ninth experimental group of the process, whether different drying temperatures have an influence on the performance of the third finish paint is detected.

In this embodiment, in the fifth experimental group, in the sixth experimental group, in the seventh experimental group, in the eighth experimental group, and in the ninth experimental group; respectively comprises two drying temperatures, wherein the first drying temperature is as follows: baking at 60deg.C for 2 hr for 30 min; the second drying temperature is as follows: baking the dried surface at 80 ℃ for 1h for 30 min.

In S2, the paint mixing proportion of the tested water paint is as follows:

1) And (2) primer: and (3) paint: fixing: water = 100:20:10;22

2) And (3) performing a primer coating: and (3) paint: fixing: water = 100:16.5:15;

3) First topcoat (RAL 9003 white): and (3) paint: fixing: water = 100:33.5:28;

4) Second topcoat (RAL 9005 black): and (3) paint: fixing: water = 100:33.5:30;

5) Third paint (Pantone 3125C blue): and (3) paint: fixing: water=100:33.5:28.

Table 2.1 is a table of performance records for the primer.

TABLE 2.1

The epoxy primer shown in Table 2.1 was dried for 30min at 60℃for 2h and at 80℃for 1h, cured for 15 days for test properties, and the test results were close without obvious differences.

Table 2.2 is a table of performance records for the middle coat paint.

TABLE 2.2

According to Table 2.2, the surface of the single-coat paint film of the waterborne automotive polyurethane intermediate coating is dried for 30min, baked for 2h at 60 ℃ and baked for 1h at 80 ℃, and in the test result, the surface is dried for 30min at 80 DEG CThe impact (recoil) resistance of the paint film is less than 10kg.cm for 1h, the paint film becomes brittle and hard, and other properties are close.

Table 2.3 is a table of performance records for the first topcoat (RAL 9003 white).

TABLE 2.3

TABLE 2.4

Table 2.4 is a table of performance records for the second topcoat (RAL 9005 black)

According to the results shown in Table 2.3, the RAL9003 white face surface dried for 30min was baked at 60℃for 2h and baked at 80℃for 1h, and the test results were close without obvious difference.

According to the table 2.4, the surface of the aqueous polyurethane finishing paint (RAL 9005 black) film is dried for 30min and baked at 80 ℃ for 1h, the limiting film thickness is less than 150 mu m, and the film is not less than 150 mu m wet film, so that prickly heat is easy to occur; in addition, other properties are equivalent to the paint film properties of a drying process in which the surface is dried for 30 minutes and baked at 60 ℃ for 2 hours.

Table 2.5 shows the performance of the third paint (Pantone 3125C blue)

TABLE 2.5

According to the results shown in Table 2.5, the aqueous polyurethane finish paint (Pantone 3125C blue) for vehicle use has a surface drying period of 30min, a drying process of baking at 60 ℃ for 2 hours and a drying process of baking at 80 ℃ for 1 hour, and the test results are close without obvious difference.

S3 specifically comprises the following steps:

S3.1, setting a tenth experimental group of the process, an eleventh experimental group of the process and a twelfth experimental group of the process; the tenth experimental group of the process comprises more than two drying temperatures of the intermediate paint, and the intermediate paint of each drying temperature is sprayed on the light plate to form paint surfaces with more than two thicknesses.

The eleventh experimental group of the process includes more than two drying temperatures of the primer surfacer, the primer surfacer of each drying temperature being sprayed on the primer to form a paint finish of more than two thicknesses.

The twelfth experimental group of the process comprises more than two drying temperatures of the intermediate paint, and the intermediate paint of each drying temperature is sprayed on the putty to form paint surfaces with more than two thicknesses.

S3.2, detecting the difference of glossiness among the middle lacquers which are sprayed on the light plate, the primer and the putty and dried at different drying temperatures; and detecting the difference of glossiness among the middle lacquers dried at the same drying temperature, wherein the thickness of the spraying layers on the light plate, the primer and the putty are different.

The method comprises the steps of comparing more than two types of temperature data and more than two types of thickness data; in a tenth experimental group of the process, whether the gloss of the middle painting is influenced by different drying temperatures and different spraying thicknesses is detected.

In an embodiment, temperature data of the process tenth experimental group, the process eleventh experimental group, and the process twelfth experimental group are the same as those of step S2; the proportion of the primer surfacer is the same as in step S2.

Table 3.1 is a gloss record table for the middle coat paint.

TABLE 3.1

According to the table 3.1, the waterborne polyurethane intermediate coat is sprayed on the primer, baked for 1h at 80 ℃ and dried, the glossiness of the paint film is generally lower than that baked for 2h at 60 ℃, the glossiness is 9% -13% different, and the thicker the paint film is, the smaller the glossiness is; spraying on putty, baking at 80 ℃ for 1h for drying, wherein the glossiness of the paint film is generally lower than that of the paint film baked at 60 ℃ for 2h, the glossiness is 7% -9% different, and the thicker the paint film is, the smaller the glossiness is.

In summary, as described in S2 and S3, the epoxy primer surface is dried for 30min, baked for 2h at 60 ℃ and baked for 1h at 80 ℃, the test performance is maintained for 15 days, the test results are close, and no obvious difference exists.

The surface dry of the paint film in the aqueous polyurethane for the vehicle is 30min, the impact resistance (recoil) of the paint film at 80 ℃ for 1h is less than 10kg.cm, the glossiness of the paint film is generally lower than that of the paint film at the surface dry of 30min at 60 ℃ for 2h, and other properties are not obviously different.

RAL9003 white dough surface is dried for 30min, and is baked for 2h according to 60 ℃ and baked for 1h according to 80 ℃ and is compared, the test result is close, and no obvious difference exists.

The surface of a water-based polyurethane finishing paint (RAL 9005 black) paint film is dried for 30min, baked for 1h at 80 ℃, and has a limiting film thickness of less than 150 mu m and a wet film of more than or equal to 150 mu m, so that prickly heat is easy to occur; in addition, other properties are equivalent to those of a paint film which is baked for 2 hours at 60 ℃ for 30 minutes

The surface drying of the waterborne polyurethane finishing paint (Pantone 3125C blue) for the vehicle is 30min, the baking process is compared with the baking process for 2h at 60 ℃ and the baking process for 1h at 80 ℃, the test results are close, and no obvious difference exists.

In S4, the paint film sprayed with the intermediate coating is: waterborne vehicle epoxy primer, putty, waterborne vehicle polyurethane primer coat and finish. The paint film without spray-on mid-coat was: epoxy primer, putty and finish paint for water-based vehicles.

When the water resistance test is carried out, the top paint of the paint film comprises a fourth top paint and a fifth top paint, the fourth top paint and the fifth top paint are horizontally arranged, the fourth top paint is arranged on one side of the paint film, and the fifth top paint is arranged on the other side of the paint film; the model number of the fourth finishing paint is 116C yellow surface; the second topcoat was 9005 black-faced.

Table 4.1 is a record of the water resistance test performed on paint films sprayed with the middle coating and paint films not sprayed with the middle coating.

TABLE 4.1

When the aging resistance test is carried out, the top coat of the paint film comprises a fourth top coat; the fourth topcoat was 116C yellow-faced. The aging resistance test is the same as that of S1.

Table 4.2 is a record of the water resistance test performed on paint films sprayed with the intermediate coating and paint films not sprayed with the intermediate coating.

TABLE 4.2

According to the table 4.2, as the putty absorbs oil and absorbs color, the finishing paint is directly sprayed on the putty and subjected to aging test, and the putty absorbs oil and absorbs color; 116C yellow surface is directly sprayed on putty (without intermediate coating), when the aging property of a paint film test UVB lamp reaches 1000 hours, obvious phenomena of light loss, color change and pulverization appear, wherein the light loss rate is more than 30%, the color change delta E is more than 8.0, the pulverization is obvious visually, the decoration is more than level 2 (the light loss rate is less than 50%, the color change delta E is less than 6, the pulverization is very slight), and the paint film is unqualified.

The 116C yellow surface is sprayed on the middle coating to test the aging of the UVB lamp, the surface of the yellow surface is visually light-lost, slightly discolored and hardly pulverized in a test of 1200h, each index meets the aging index requirement (the color-changing delta E of measured data is less than 2.0 and the light-loss rate is less than 15%), the 116C yellow surface is directly sprayed on the putty to be completely dried and 33 degrees, then the aging of the UVB lamp is tested, and the phenomena of light loss, pulverization and discoloration are obviously easy to occur compared with the aging result of the paint film on the middle coating.

In conclusion, the coating system of the primer, the putty, the middle coating and the finish paint is resistant to water at 40 ℃ for 13 days, and the paint film is basically unchanged by eyes and is qualified.

The primer, putty and finish coating system resists water at 40 ℃ for 13 days, the paint film is poor, the wrinkling is obvious, the paint film is visibly obvious in light loss, and the paint film is unqualified.

And (3) a coating system of primer, putty, middle coating and finish paint, wherein the aging test of a UVB lamp is carried out for 1200 hours, the decorative level is 2, and the paint is qualified.

The coating system of the primer, putty and finish paint has the ageing test of a UVB lamp for 1000 hours, the decorative performance is more than grade 2, and the coating system is unqualified.

1-8, S5, carrying out aging resistance test on paint films with different spraying methods, and detecting the change of gloss and color difference values of the paint films with different spraying methods; and (3) carrying out ageing resistance test on different paint films with the same spraying method, and detecting the change of gloss and color difference values of the different paint films with the same spraying method.

Salt spray resistance tests are carried out on the priming paint and the paint film with different spraying methods, and the difference of gloss and color difference values of the priming paint and the paint film with different spraying methods is detected; and (3) carrying out salt spray resistance test on different primer and paint films with the same spraying method, detecting whether the foaming phenomenon and the rusting phenomenon of the different primer and paint films sprayed by the same spraying method are different, and determining paint film aging test data and salt spray resistance test data according to the foaming phenomenon and the rusting phenomenon of the paint films.

S5.1, salt spray resistance test specifically comprises the following steps: s5.1, setting a thirteenth experimental group, a fourteenth experimental group, a fifteenth experimental group and a sixteenth experimental group; spraying the primer by an air spraying method in a thirteenth experimental group of the process; spraying the primer by an airless spraying method in a fourteenth experimental group of the process; spraying the first paint film by an air spraying method in a fifteenth experiment group of the process; in a sixteenth experimental group of the process, spraying the first paint film by an airless spraying method; the first paint film is formed by spraying a primer, a middle paint and a first surface paint in sequence. .

S5.2, performing salt spray resistance tests on a thirteenth process experiment group and a fourteenth process experiment group; in this example, the salt spray was used to etch the surfaces of the thirteenth experimental set of processes and the fourteenth experimental set of processes; detecting whether a foaming phenomenon and a rusting phenomenon occur in a thirteenth process experiment set and a fourteenth process experiment set within a preset period of time; the performance difference between the primers sprayed by different spraying methods was detected.

S5.3, performing salt spray resistance tests on a fifteenth process experiment group and a sixteenth process experiment group. Salt spray resistance test, namely using salt spray to corrode the surface of the fifteenth experimental group and the surface of the sixteenth experimental group; detecting whether a foaming phenomenon and a rusting phenomenon occur in a fifteenth experimental group of the process and a sixteenth experimental group of the process within a preset time period; and detecting the performance difference between the top coats sprayed by different spraying methods.

S5.4, performing salt spray resistance tests on the thirteenth experimental group and the fifteenth experimental group, and in the embodiment, corroding the surfaces of the thirteenth experimental group and the fifteenth experimental group by using salt spray; and detecting whether the thirteenth experimental group and the fourteenth experimental group have foaming and rusting phenomena within a preset time period, and detecting the performance difference between the primer and the paint film sprayed by the same spraying method.

S5.5, performing salt spray resistance tests on the fourteenth experimental group and the sixteenth experimental group, and in the embodiment, corroding the surfaces of the fourteenth experimental group and the sixteenth experimental group by using salt spray; detecting whether a foaming phenomenon and a rusting phenomenon occur in a fourteenth process experiment set and a sixteenth process experiment set within a preset period of time; the performance difference between the primer and the paint film sprayed by the same spraying method was detected.

In S5, the aging resistance test includes the steps of:

S5.6, performing aging resistance test on a fifteenth process experiment group and a sixteenth process experiment group; in this example, an aging resistance test was performed using UVB lamps to irradiate fifteen experimental groups and a sixteenth experimental group of the process; detecting the change of the gloss and color difference values of a fifteenth experimental group of the process within a preset duration; and detecting the change of the gloss and color difference values of the sixteenth experimental group of the process within a preset time period.

The method uses salt fog to carry out corrosion to realize salt fog resistance test; the aging resistance test is realized by irradiation with a UVB lamp, and the method is simple. Comparing the primer formed by air spraying with the primer formed by airless spraying, and detecting the difference of salt spray resistance of the primer under different spraying methods; and comparing the first paint film formed by air spraying with the first paint film formed by airless spraying, and detecting the difference of salt spray resistance and ageing resistance of the paint films under different spraying methods. And simultaneously comparing air spraying to form a primer and a first paint film, airless spraying to form the primer and the first paint film, and detecting the difference of salt spray resistance of the primer and the first paint film under the same spraying method. In this example, the first paint film was a composite paint film formed by spraying in sequence with a primer, a middle paint, and a second top paint (RAL 9005 black). In this embodiment, Δ1 represents brightness, Δa represents red-green, Δb represents yellow-green, and Δe represents total color difference.

Table 5.1 is a data record of the irradiation of air-sprayed paint films using UVB lamps in the fifteenth experimental set of processes.

TABLE 5.1

Table 5.2 is a table of data recordings of the irradiation of airless sprayed paint films using UVB lamps in the sixteenth experimental group of the process.

TABLE 5.2

The first paint film is sprayed on the plate body for detection, wherein Delta1 represents brightness, deltaa represents red and green, deltab represents yellow and green, and DeltaE represents total chromatic aberration.

According to table 5.1, the air-sprayed paint film was slightly changed in view of the surface of the panel when irradiated with UVB lamp for 1500 hours, Δe=1.42, and slightly lost in light. According to table 5.2, the airless sprayed first paint film was slightly blinded to the surface of the panel when irradiated with UVB lamp for 1500h, Δe=1.37, and slightly lost light. When the aging resistance test is carried out, the spraying effect of the airless spraying first paint film is close to the testing result of the air spraying first paint film, and further, the fact that the aging resistance of the paint film is not affected by the two spraying methods of air spraying and airless spraying is judged.

Table 5.3 is a data record of paint film corrosion on air spray using salt spray in the fifteenth experimental set of processes.

TABLE 5.3

The first paint film is sprayed on the plate body for detection, and when salt fog is corroded to 1500 hours, the surface of the plate body is slightly changed visually, and the bubbling phenomenon and the rusting phenomenon do not occur according to the table 5.3.

Table 5.4 is a data record of corrosion of airless sprayed paint films using salt spray in the sixteenth experimental set of processes.

TABLE 5.4

The first paint film is sprayed on the plate body for detection, and when salt fog is corroded to 1500 hours, the surface of the plate body is slightly changed visually, and the bubbling phenomenon and the rusting phenomenon do not occur according to the table 5.4. When salt spray resistance tests are carried out, the spraying effect of the airless spraying first paint film is close to the testing result of the air spraying first paint film, the spraying effect of the airless spraying paint film is close to the spraying effect of the air spraying paint film, and further it is judged that the salt spray resistance of the paint film is not affected by the two spraying methods of air spraying and airless spraying.

Table 5.5 is a data record of corrosion of air sprayed primer using salt spray in the thirteenth experimental set of processes.

TABLE 5.5

Table 5.6 is a data record of corrosion of airless sprayed primer using salt spray in the fourteenth experimental set of processes.

TABLE 5.6

The primer was sprayed on the plate body for detection, and when the air sprayed primer was corroded to 1500 hours with salt fog, the surface of the plate body was visually unchanged, and no foaming and rust occurred, as shown in table 5.5. According to Table 5.6, the surface of the airless paint was visually unchanged when the salt spray was corroded to 1500 hours, and foaming and rusting were not caused.

When salt spray resistance tests are carried out, the spraying effect of the airless spraying primer is close to the testing result of the air spraying primer, and the spraying effect of the airless spraying primer is close to the spraying effect of the air spraying primer, so that the salt spray resistance of the primer is not affected by the two spraying methods of air spraying and airless spraying.

Simultaneously comparing the thirteenth experimental set of the process with the fifteenth experimental set of the process, and combining tables 5.5 and 5.3; the spray coating of the multi-layer paint surface does not affect the salt spray resistance by comparing the spray coating of the one-layer paint surface with the spray coating of the multi-layer paint surface and by adopting an air spray coating mode.

A fourteenth experimental set of processes was compared to a sixteenth experimental set of processes, as shown in table 5.6 in combination with table 5.4; and compared with the spraying of a plurality of layers of paint surfaces, the spraying of the plurality of layers of paint surfaces in an airless spraying manner does not influence the salt spray resistance.

Meanwhile, the aging test and the salt spray resistance test are also carried out on the water paint films with different colors.

S5.1 also includes S5.7-S5.9.

S5.7, setting a seventeenth experimental group of the process and an eighteenth experimental group of the process; spraying the second paint film by an air spraying method in a seventeenth experiment group of the process; spraying a second paint film by an airless spraying method in an eighteenth experimental group of the process; the second paint film is formed by sequentially spraying a primer, a middle paint and a second finish paint; the second topcoat is inconsistent with the first topcoat in color.

And S5.8, performing ageing resistance test on the fifteenth experimental group of the process and the seventeenth experimental group of the process, and detecting performance differences between different enamels sprayed by the same spraying method. In this example, a fifteenth experimental set of processes and a seventeenth experimental set of processes were irradiated using UVB lamps; detecting the change of the gloss and color difference values of a fifteenth experimental group of the process within a preset duration; detecting the change of the gloss and color difference values of a seventeenth experimental group of the process within a preset time period;

And S5.9, performing aging resistance test on the sixteenth experimental group and the eighteenth experimental group of the process, and detecting the performance difference between different enamels sprayed by the same spraying method. In this example, a fifteenth experimental set of processes and a seventeenth experimental set of processes were irradiated using UVB lamps; detecting the change of the gloss and color difference values of a fifteenth experimental group of the process within a preset duration; detecting the change of the gloss and color difference values of a seventeenth experimental group of the process within a preset time period;

Table 5.7 is a data record of the irradiation of air-sprayed paint films using UVB lamps in the seventeenth experimental set of processes.

TABLE 5.7

The second paint film was sprayed on the panel for detection, and the air sprayed second paint film was slightly changed in view of the surface of the panel when irradiated with UVB light for 1500 hours, Δe=2.39, and slightly lost light, as shown in table 5.7. ΔE is less than 3.0, within the allowable range of chromatic aberration. By combining the table 5.1 with the table 5.7, the gloss and color difference values are relatively close, the test result of the first air-sprayed paint film and the second air-sprayed paint film is close, and further, the air-spraying method is judged to have no influence on the ageing resistance of different paint films.

Table 5.8 is a table of data recordings of the irradiation of airless sprayed paint films using UVB lamps in the process eighteenth experimental group.

TABLE 5.8

The second paint film was sprayed on the panel for detection, and the air sprayed second paint film was slightly changed in view of the surface of the panel when irradiated with UVB light for 1500 hours, Δe=2.37, and slightly lost light, as shown in table 5.7. ΔE is less than 3.0, within the allowable range of chromatic aberration. By combining the table 5.2 with the table 5.8, the gloss and color difference values are relatively close, and the test results of the airless spraying first paint film and the airless spraying second paint film are close, so that the airless spraying method is judged to have no influence on the ageing resistance of different paint films.

Further, S5 also includes S5.10 and 5.11;

s5.10, salt spray resistance tests are carried out on the fifteenth experimental group of the process and the seventeenth experimental group of the process, and the performance difference between different enamels sprayed by the same spraying method is detected.

S5.11, performing salt spray resistance tests on a sixteenth experimental group of the process and an eighteenth experimental group of the process, and detecting performance differences between different enamels sprayed by the same spraying method.

In S5.10 and S5.11, it was checked whether the difference in the bubbling phenomenon and the rusting phenomenon occurred in the different paint films of the same spraying method.

Table 5.10 is a data record of paint film corrosion on air spray using salt spray in the seventeenth experimental set of processes.

TABLE 5.9

According to Table 5.9, the second paint film sprayed with air was slightly changed in the surface of the plate when the salt spray was corroded to 1500 hours, and no bubbling and rusting occurred. When salt spray resistance tests are carried out, the spraying effect of the first air spraying paint film is close to the testing result of the second air spraying paint film, the spraying effect of the first air spraying paint film is close to the spraying effect of the second air spraying paint film, and further, the fact that the salt spray resistance of different paint films is not influenced by the air spraying method is judged.

Table 5.10 is a data record of corrosion of airless sprayed paint films using salt spray in the eighteenth experimental set of processes.

TABLE 5.10

According to Table 5.10, the surface of the plate was slightly changed in view of the second paint film sprayed without gas when the salt spray was corroded to 1500 hours, and no bubbling and rusting occurred. When salt spray resistance tests are carried out, the spraying effect of the first airless paint film is close to the testing result of the second airless paint film, the spraying effect of the first airless paint film is close to the spraying effect of the second airless paint film, and further, the fact that the airless spraying method has no influence on salt spray resistance of different paint films is judged.

In conclusion, the salt spray resistance and the ageing resistance of the paint surface are not affected by the airless spraying mode and the air spraying mode.

The step S6 includes:

The air spraying and the airless spraying have no influence on the aging test performance of the water-based polyurethane finish paint; the air spraying and airless spraying have no influence on the salt spray resistance test performance of the water-based epoxy primer and the water-based polyurethane finish paint; the aging resistance requirement of the water-based polyurethane finish paint is that the UVB-resistant lamp is 1200h, the delta E is less than or equal to 3.0, and the light loss rate is less than or equal to 30 percent, so that the requirement of 15 years of outdoor use can be met; the salt spray resistance requirement of the waterborne polyurethane finish paint and the waterborne epoxy primer is 1500 hours, the adhesive force is less than or equal to 1 level, the rust width is less than or equal to 2mm (one side), and the requirement of 15 years of outdoor use can be possibly met.

And detecting different factors under different conditions, and detecting factors influencing the service life of the paint film. With reference to the embodiment, the ageing resistance of the paint film is hardly affected by different paint preparation modes; the thickness of the paint film has almost no influence on the ageing resistance of the paint film; different baking temperatures have an influence on the paint film performance; whether the intermediate coating is provided has a great influence on the water resistance and ageing resistance of the paint film; the different spraying methods have no influence on the water resistance and ageing resistance of the paint film.

Claims

1. The method for testing the reliability of the whole life cycle of the water paint is characterized by comprising the following steps of: the method comprises a preparation process detection method of a paint film;

S1, paint films with different dry film thicknesses are prepared by the same paint matching process; carrying out ageing resistance test on paint films with the same dry film thickness by different paint preparation processes; detecting the gloss, the extinction ratio and the color difference values of paint films of different paint preparation processes; detecting the gloss, the extinction rate and the color difference values of paint films with different thicknesses; testing ageing resistance differences among paint films of different paint preparation processes and among paint films of different thicknesses;

S2, performing performance test on the priming paint with different drying temperatures, the middle painting with different drying temperatures and the finishing paint with different drying temperatures; testing performance differences among the priming paint with different drying temperatures, the middle paint with different drying temperatures and the layer paint with different drying temperatures;

S3, detecting glossiness of the intermediate paint sprayed on the light plate, the primer or the putty and with different thickness; detecting glossiness of the paint sprayed on the light plate, the primer or the putty and having different drying temperatures; testing the gloss difference of the middle coating with different thickness and different drying temperature on the light plate, the primer or the putty;

S4, carrying out water resistance and aging resistance tests on the paint film sprayed with the middle coating and the paint film without the middle coating; testing the difference in water resistance between the coating with the middle coating and the coating without the middle coating; testing the aging resistance difference between the coating with the middle coating and the coating without the middle coating;

salt spray resistance tests are carried out on the priming paint and the paint film with different spraying methods, and the difference of gloss and color difference values of the priming paint and the paint film with different spraying methods is detected; salt spray resistance tests are carried out on different primer and paint films which are the same in spraying method, and whether the foaming phenomenon and the rusting phenomenon of the different primer and paint films sprayed by the same spraying method are different is detected;

2. The method for testing the full life cycle reliability of the water paint according to claim 1, wherein the method comprises the following steps: s1 specifically comprises the following steps:

S1.1, setting a first experimental group of a process, a second experimental group of the process, a third experimental group of the process and a fourth experimental group of the process; the first experiment group and the second experiment group have the same paint preparing process, and the dry film thicknesses of the paint are different; the third experiment group of the process and the fourth experiment group of the process are the same in paint preparing process, and the dry film thicknesses of the paint are different; the first experiment group of the process and the third experiment group of the process are different in paint preparing process, and the dry film thickness of the paint is the same; the process second experimental group and the process fourth experimental group are different in paint preparation process, and the thickness of the paint dry film is the same;

S1.2, irradiating a first experiment set, a second experiment set, a third experiment set and a fourth experiment set of the process by using a UVB lamp and a xenon lamp respectively;

3. The method for testing the full life cycle reliability of the water paint according to claim 1, wherein the method comprises the following steps: the finish paint is a first finish paint, a second finish paint or a third finish paint; s2 specifically comprises the following steps:

S2.1, setting a fifth experimental group, a sixth experimental group, a seventh experimental group, an eighth experimental group and a ninth experimental group; the fifth experimental group of the process comprises more than two drying temperatures of the primer; the sixth experimental group of the process comprises more than two drying temperatures of the middle coating; the seventh experimental group of the process comprises more than two drying temperatures of the first finishing coat; the eighth experimental group of the process comprises two drying temperatures above the second finish paint; the ninth experimental group of the process comprises two drying temperatures above the third finish paint;

4. A method for testing the full life cycle reliability of water paint according to claim 3, wherein: s3 specifically comprises the following steps:

s3.1, setting a tenth experimental group of the process, an eleventh experimental group of the process and a twelfth experimental group of the process; the tenth experimental group of the process comprises more than two drying temperatures of the intermediate paint, and the intermediate paint at each drying temperature is sprayed on the light plate to form paint surfaces with more than two thicknesses;

The eleventh experimental group of the process comprises more than two drying temperatures of the intermediate coat, wherein the intermediate coat at each drying temperature is sprayed on the primer to form a paint surface with more than two thicknesses;

The twelfth experimental group of the process comprises more than two drying temperatures of the intermediate paint, and the intermediate paint at each drying temperature is sprayed on the putty to form paint surfaces with more than two thicknesses;

5. A method for testing the full life cycle reliability of water paint according to claim 3, wherein: s5.1, the salt spray resistance testing method specifically comprises the following steps:

S5.1, setting a thirteenth experimental group, a fourteenth experimental group, a fifteenth experimental group and a sixteenth experimental group; spraying the primer by an air spraying method in a thirteenth experimental group of the process; spraying the primer by an airless spraying method in a fourteenth experimental group of the process; spraying the first paint film by an air spraying method in a fifteenth experiment group of the process; in a sixteenth experimental group of the process, spraying the first paint film by an airless spraying method; the first paint film is formed by sequentially spraying a primer, a middle paint and a first finish;

S5.2, performing salt spray resistance tests on the thirteenth experimental group and the fourteenth experimental group, and detecting performance differences among the primer sprayed by different spraying methods;

S5.3, carrying out salt spray resistance tests on the fifteenth experimental group and the sixteenth experimental group of the process, and detecting performance differences among the top paints sprayed by different spraying methods;

s5.4, performing salt spray resistance tests on the thirteenth experimental group and the fifteenth experimental group of the process, and detecting the performance difference between the primer and the paint film sprayed by the same spraying method;

S5.5, performing salt spray resistance tests on the fourteenth experimental group and the sixteenth experimental group, and detecting the performance difference between the primer and the paint film sprayed by the same spraying method.

6. The method for testing the full life cycle reliability of the water paint according to claim 5, wherein the method comprises the following steps:

S5.2, corroding the surface of the thirteenth experimental group and the surface of the fourteenth experimental group by using salt mist; and detecting whether the thirteenth experimental group and the fourteenth experimental group have foaming and rusting phenomena within a preset time period.

7. The method for testing the full life cycle reliability of the water paint according to claim 2, wherein the method comprises the following steps of:

S5.3, using salt mist to corrode the surface of the fifteenth experimental group and the surface of the sixteenth experimental group; and detecting whether the fifteenth experimental group and the sixteenth experimental group of the process have foaming and rusting phenomena within a preset time period.

8. The method for testing the full life cycle reliability of the water paint according to claim 2, wherein the method comprises the following steps of:

S5.4, corroding the surfaces of the thirteenth experimental group and the fifteenth experimental group by using salt mist; detecting whether a foaming phenomenon and a rusting phenomenon occur in a thirteenth process experiment set and a fourteenth process experiment set within a preset period of time;

S5.5, using salt mist to corrode the surface of the fourteenth experimental group and the surface of the sixteenth experimental group; and detecting whether the foaming phenomenon and the rusting phenomenon occur in the fourteenth experimental group and the sixteenth experimental group of the process within a preset time period.

9. The method for testing the full life cycle reliability of the water paint according to claim 2, wherein the method comprises the following steps of: s5, further comprising the following steps:

s5.6, performing an aging resistance test on the fifteenth experimental group of the process and the sixteenth experimental group of the process, and detecting performance differences between the top paints sprayed by different spraying methods;

S5.7, setting a seventeenth experimental group of the process and an eighteenth experimental group of the process; spraying the second paint film by an air spraying method in a seventeenth experiment group of the process; spraying a second paint film by an airless spraying method in an eighteenth experimental group of the process; the second paint film is formed by sequentially spraying a primer, a middle paint and a second finish paint; the color of the second finishing paint is inconsistent with that of the first finishing paint;

S5.8, performing aging resistance test on the fifteenth experimental group of the process and the seventeenth experimental group of the process, and detecting performance differences between different enamels sprayed by the same spraying method;

and S5.9, performing aging resistance test on the sixteenth experimental group and the eighteenth experimental group of the process, and detecting the performance difference between different enamels sprayed by the same spraying method.

10. The method for testing the full life cycle reliability of the water-based paint according to claim 9, wherein the method comprises the following steps of:

S5.6, irradiating a fifteenth experimental group of the process and a sixteenth experimental group of the process by using a UVB lamp; detecting the change of the gloss and color difference values of a fifteenth experimental group of the process within a preset duration; detecting the change of the gloss and color difference values of a sixteenth experimental group of the process within a preset time period;

s5.8, irradiating a fifteenth experimental group of the process and a seventeenth experimental group of the process by using a UVB lamp; detecting the change of the gloss and color difference values of a fifteenth experimental group of the process within a preset duration; detecting the change of the gloss and color difference values of a seventeenth experimental group of the process within a preset time period;

S5.9, irradiating a sixteenth experimental group and an eighteenth experimental group of the process by using a UVB lamp; detecting the change of the gloss and color difference values of a sixteenth experimental group of the process within a preset time period; and detecting the change of the gloss and color difference values of the eighteenth experimental group of the process within a preset time period.