1.聚氨酯稀释剂 Polyurethane diluentPainting film hardness testing

DreamThinner 10:聚氨酯稀释剂是配合聚氨酯基础树脂混合使用，可以降低固化体系粘度，增加流动性，延长使用寿命，便于大面积施工；改善了操作性的同时，又不影响固化物的基本性能。 Polyurethane diluent is mixed with polyurethane base resin to reduce the viscosity of the curing system, increase flowability, extend service life, and facilitate large-scale construction; Improved operability without affecting the basic properties of the cured product

聚氨酯稀释剂 Polyurethane diluentHardness is the 聚氨酯稀释剂 Polyurethane diluentpaint film to foreign objects invading its surface.DreamThinner 10Film hardness is one of the important properties of its mechanical strength. Generally speaking, the hardness of lacquer film is related to the material that compose lacquer and dry degree, such as lacquer film dries more thoroughly, hardness is higher.currently DreamThinner 10lacquer film hardness determination has the following four methods: swing rod hardness determination method, swater hardness determination method, climann hardness determination method and pencil hardness determination method.

National standard GB / T6739-1996 stipulates the use of known hardness mark pencil scratch film, with the pencil hardness mark of the coating hardness determination method, can use test machine method, can also use manual method.

2. method of operation

1. Manual method:

1) The test material is a group of Chinese brand advanced drawing pencils, from 9H to 6B has different hardness, 9H is the hardest, 6B is the softest;

2) Cut the pencil off the wooden pole to expose the lead core by about 3mm, and grind with sandpaper to the end surface level with sharp edge, ready for use;

3) The pencil and the bottom plate into 45 Angle, the pencil scratches the coating surface, the refill is not broken as the degree, and then smear the surface push pressure, the speed is about 1 cm/s, each scratch one, to the core to refill, the same hardness mark of the pencil repeatedly scratch five;

4) If there are two or more membranes that are not bruised, replace the previous pencil with the higher hardness mark for the same experiment;

5) Cut through two or more pencils, write down the hardness mark of the pencil, and take the second hardness mark as the pencil hardness of the film.

2. Test machine method:

1) When using the paint film pencil hardness scratch instrument, the pencil preparation work is the same as above;

2) Face the coating film of the plate to be tested upward, place it horizontally and fix it on the experimental platform of the test machine;

3) The heavy object of the test machine contacts the tip of the pencil core through the intersection point of the coating surface through the vertical line of the center of gravity, and the pencil is fixed on the fixture;

4) Adjust the balance weight hammer, so that the pencil load of the test sample is in a bad state, and then tighten the fixed screws;

5) Make the pencil off the coating surface and fix the connecting rod;

6) Add 1.00kg plus or minus 0.05kg weight to the weight placement table, and relax the fixing screws;

7) Make the tip of the pencil lead touch the coating surface, and add the load of the weight to the tip of the pencil;

8) Shake the hand wheel at constant speed, make the sample move horizontally by 3mm in the opposite direction of the cartridge, and let the cartridge scratch the film surface, with the movement speed of 0.5 mm/s;

9) 5 sections after the test position, and the evaluation method is the same as the manual hardness measurement method.

9) 5 sections after the test position, and the evaluation method is the same as the manual hardness measurement method.