"Performance index" and detection method of water-based paint!

The apparent performance of water-based paint: the apparent performance refers to the generally intuitive feeling, such as its leveling, anti-sagging, drying, sanding, color accuracy and other properties

Intrinsic properties of water-based paint: The evaluation of intrinsic properties is an important indicator that determines the quality of water-based paint

1.

Test method: take a sample 20 minutes after the product is finished, adjust the temperature of the paint sample (15°C in winter, 25°C in summer), and then test again the next day

2.

Testing method: T=160℃ (testing for 2 hours), the weight of the paint sample is 3-5 grams, pay attention to spread the paint sample evenly

3.

The hardness of water-based paint is about HB for one-component products, and about H for two-component products

4.

5.

Detection method: the black glass plate has a scraping thickness of 250 microns, baking at 45°C for 2 hours, calibrate the photometer, and then test the product

6.
Anti-blocking:

Stack the six boards (the board is 150mmx70mm) and place them from top to bottom in the following order: one face up, two face down, one face up, and two face down
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To ensure that the two pieces are in face-to-face contact and the two pieces are in back-to-back contact, apply a weight with a diameter of about 70mm and a mass of 500g on the sample plate
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Drying conditions: surface drying at room temperature 25℃-30℃ for 20 minutes, then drying at 70℃ for 4 hours; finally cooling at room temperature 25℃-30℃ for 60 minutes, placing in an oven at 50℃ for 4 hours, after removing the pressure, the samples are separated, and the separation is checked.
The degree of difficulty of the time and the degree of damage (visible traces) on the surface of the coating film.
The result is judged in two forms: "adhesion level" and "surface damage level".
Each form is divided into six levels according to different degrees.
The details are as follows
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 Adhesion grade points surface damage grade

A=Free fall separation 0=No damage

B=Slightly tapped to separate 1=<1% damage

C=Separation after applying slight tension 2=1%—5% damage

D=Separation after applying moderate tension 3=6%-20% damage

E=Separation after applying extreme tension 4=21%-50% damage

7.
Fineness: Fineness is a standard for checking the particle size or uniformity of dispersion of pigments in water-based paint, expressed in micrometers (μm)
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The smaller the fineness, the smoother the coating film, and vice versa
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Detection method: When the dispersion time is sufficient, take an appropriate amount of product and scrape it with a scraper fineness meter, and read the fineness data within ten seconds
.

8.
Impact resistance: It is also an important indicator of the flexibility of the paint film
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This index is particularly significant for metallic paints.
The better the impact resistance, the less likely the paint film will appear whitening and delamination under impact conditions
.

9.
Cold resistance: refers to the cold resistance of the paint film under low temperature conditions
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This performance is a prerequisite for determining whether the furniture can be used in cold winter areas such as northern China
.

10.
Heat resistance: The passing of this performance is to ensure the heating requirements of the paint film for daily necessities such as hot water and teapots under general conditions of use
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9.
Temperature resistance: This index is a higher level of paint film requirements
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Only the paint film that can withstand the hot and cold cycle test can obtain the basic conditions for safe use in any climate
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10.
Yellowing resistance: It is the indicator of the color retention performance of the paint film during use.
Generally, the color difference value before and after UV light or sun exposure is used to quantitatively characterize the degree of discoloration
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The smaller the color difference value, the better the color retention, and a reasonably designed paint film should have a smaller color difference change under the test conditions
.